libmicrohttpd

HTTP/1.x server C library (MHD 1.x, stable)
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microhttpd.h (257528B)


      1 /*
      2      This file is part of libmicrohttpd
      3      Copyright (C) 2006-2021 Christian Grothoff (and other contributing authors)
      4      Copyright (C) 2014-2023 Evgeny Grin (Karlson2k)
      5 
      6      This library is free software; you can redistribute it and/or
      7      modify it under the terms of the GNU Lesser General Public
      8      License as published by the Free Software Foundation; either
      9      version 2.1 of the License, or (at your option) any later version.
     10 
     11      This library is distributed in the hope that it will be useful,
     12      but WITHOUT ANY WARRANTY; without even the implied warranty of
     13      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     14      Lesser General Public License for more details.
     15 
     16      You should have received a copy of the GNU Lesser General Public
     17      License along with this library; if not, write to the Free Software
     18      Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
     19 */
     20 
     21 /**
     22  * @file microhttpd.h
     23  * @brief public interface to libmicrohttpd
     24  * @author Christian Grothoff
     25  * @author Karlson2k (Evgeny Grin)
     26  * @author Chris GauthierDickey
     27  *
     28  * All symbols defined in this header start with MHD.  MHD is a small
     29  * HTTP daemon library.  As such, it does not have any API for logging
     30  * errors (you can only enable or disable logging to stderr).  Also,
     31  * it may not support all of the HTTP features directly, where
     32  * applicable, portions of HTTP may have to be handled by clients of
     33  * the library.
     34  *
     35  * The library is supposed to handle everything that it must handle
     36  * (because the API would not allow clients to do this), such as basic
     37  * connection management; however, detailed interpretations of headers
     38  * -- such as range requests -- and HTTP methods are left to clients.
     39  * The library does understand HEAD and will only send the headers of
     40  * the response and not the body, even if the client supplied a body.
     41  * The library also understands headers that control connection
     42  * management (specifically, "Connection: close" and "Expect: 100
     43  * continue" are understood and handled automatically).
     44  *
     45  * MHD understands POST data and is able to decode certain formats
     46  * (at the moment only "application/x-www-form-urlencoded" and
     47  * "multipart/formdata"). Unsupported encodings and large POST
     48  * submissions may require the application to manually process
     49  * the stream, which is provided to the main application (and thus can be
     50  * processed, just not conveniently by MHD).
     51  *
     52  * The header file defines various constants used by the HTTP protocol.
     53  * This does not mean that MHD actually interprets all of these
     54  * values.  The provided constants are exported as a convenience
     55  * for users of the library.  MHD does not verify that transmitted
     56  * HTTP headers are part of the standard specification; users of the
     57  * library are free to define their own extensions of the HTTP
     58  * standard and use those with MHD.
     59  *
     60  * All functions are guaranteed to be completely reentrant and
     61  * thread-safe (with the exception of #MHD_set_connection_value,
     62  * which must only be used in a particular context).
     63  *
     64  *
     65  * @defgroup event event-loop control
     66  * MHD API to start and stop the HTTP server and manage the event loop.
     67  * @defgroup response generation of responses
     68  * MHD API used to generate responses.
     69  * @defgroup request handling of requests
     70  * MHD API used to access information about requests.
     71  * @defgroup authentication HTTP authentication
     72  * MHD API related to basic and digest HTTP authentication.
     73  * @defgroup logging logging
     74  * MHD API to manage logging and error handling
     75  * @defgroup specialized misc. specialized functions
     76  * This group includes functions that do not fit into any particular
     77  * category and that are rarely used.
     78  */
     79 
     80 #ifndef MHD_MICROHTTPD_H
     81 #define MHD_MICROHTTPD_H
     82 
     83 #ifndef __cplusplus
     84 #  define MHD_C_DECLRATIONS_START_HERE_   /* Empty */
     85 #  define MHD_C_DECLRATIONS_FINISH_HERE_  /* Empty */
     86 #else  /* __cplusplus */
     87 /* *INDENT-OFF* */
     88 #  define MHD_C_DECLRATIONS_START_HERE_   extern "C" {
     89 #  define MHD_C_DECLRATIONS_FINISH_HERE_  }
     90 /* *INDENT-ON* */
     91 #endif /* __cplusplus */
     92 
     93 
     94 MHD_C_DECLRATIONS_START_HERE_
     95 
     96 
     97 /**
     98  * Current version of the library in packed BCD form.
     99  * @note Version number components are coded as Simple Binary-Coded Decimal
    100  * (also called Natural BCD or BCD 8421). While they are hexadecimal numbers,
    101  * they are parsed as decimal numbers.
    102  * Example: 0x01093001 = 1.9.30-1.
    103  */
    104 #define MHD_VERSION 0x01001000
    105 
    106 /* If generic headers don't work on your platform, include headers
    107    which define 'va_list', 'size_t', 'ssize_t', 'intptr_t', 'off_t',
    108    'uint8_t', 'uint16_t', 'int32_t', 'uint32_t', 'int64_t', 'uint64_t',
    109    'struct sockaddr', 'socklen_t', 'fd_set' and "#define MHD_PLATFORM_H" before
    110    including "microhttpd.h". Then the following "standard"
    111    includes won't be used (which might be a good idea, especially
    112    on platforms where they do not exist).
    113    */
    114 #ifndef MHD_PLATFORM_H
    115 #if defined(_WIN32) && ! defined(__CYGWIN__) && \
    116   ! defined(_CRT_DECLARE_NONSTDC_NAMES)
    117 /* Declare POSIX-compatible names */
    118 #define _CRT_DECLARE_NONSTDC_NAMES 1
    119 #endif /* _WIN32 && ! __CYGWIN__ && ! _CRT_DECLARE_NONSTDC_NAMES */
    120 #include <stdarg.h>
    121 #include <stdint.h>
    122 #include <sys/types.h>
    123 #if ! defined(_WIN32) || defined(__CYGWIN__)
    124 #include <unistd.h>
    125 #include <sys/time.h>
    126 #include <sys/socket.h>
    127 #else  /* _WIN32 && ! __CYGWIN__ */
    128 #include <ws2tcpip.h>
    129 #if defined(_MSC_FULL_VER) && ! defined(_SSIZE_T_DEFINED)
    130 #define _SSIZE_T_DEFINED
    131 typedef intptr_t ssize_t;
    132 #endif /* !_SSIZE_T_DEFINED */
    133 #endif /* _WIN32 && ! __CYGWIN__ */
    134 #endif
    135 
    136 #if defined(__CYGWIN__) && ! defined(_SYS_TYPES_FD_SET)
    137 /* Do not define __USE_W32_SOCKETS under Cygwin! */
    138 #error Cygwin with winsock fd_set is not supported
    139 #endif
    140 
    141 #ifdef __has_attribute
    142 #if __has_attribute (flag_enum)
    143 #define _MHD_FLAGS_ENUM __attribute__((flag_enum))
    144 #endif /* flag_enum */
    145 #if __has_attribute (enum_extensibility)
    146 #define _MHD_FIXED_ENUM __attribute__((enum_extensibility (closed)))
    147 #endif /* enum_extensibility */
    148 #endif /* __has_attribute */
    149 
    150 #ifndef _MHD_FLAGS_ENUM
    151 #define _MHD_FLAGS_ENUM
    152 #endif /* _MHD_FLAGS_ENUM */
    153 #ifndef _MHD_FIXED_ENUM
    154 #define _MHD_FIXED_ENUM
    155 #endif /* _MHD_FIXED_ENUM */
    156 
    157 #define _MHD_FIXED_FLAGS_ENUM _MHD_FIXED_ENUM _MHD_FLAGS_ENUM
    158 
    159 /**
    160  * Operational results from MHD calls.
    161  */
    162 enum MHD_Result
    163 {
    164   /**
    165    * MHD result code for "NO".
    166    */
    167   MHD_NO = 0,
    168 
    169   /**
    170    * MHD result code for "YES".
    171    */
    172   MHD_YES = 1
    173 
    174 } _MHD_FIXED_ENUM;
    175 
    176 /**
    177  * Constant used to indicate unknown size (use when
    178  * creating a response).
    179  */
    180 #ifdef UINT64_MAX
    181 #define MHD_SIZE_UNKNOWN UINT64_MAX
    182 #else
    183 #define MHD_SIZE_UNKNOWN  ((uint64_t) -1LL)
    184 #endif
    185 
    186 #define MHD_CONTENT_READER_END_OF_STREAM ((ssize_t) -1)
    187 #define MHD_CONTENT_READER_END_WITH_ERROR ((ssize_t) -2)
    188 
    189 #ifndef _MHD_EXTERN
    190 #if defined(_WIN32) && defined(MHD_W32LIB)
    191 #define _MHD_EXTERN extern
    192 #elif defined(_WIN32) && defined(MHD_W32DLL)
    193 /* Define MHD_W32DLL when using MHD as W32 .DLL to speed up linker a little */
    194 #define _MHD_EXTERN __declspec(dllimport)
    195 #else
    196 #define _MHD_EXTERN extern
    197 #endif
    198 #endif
    199 
    200 #ifndef MHD_SOCKET_DEFINED
    201 /**
    202  * MHD_socket is type for socket FDs
    203  */
    204 #if ! defined(_WIN32) || defined(_SYS_TYPES_FD_SET)
    205 #define MHD_POSIX_SOCKETS 1
    206 typedef int MHD_socket;
    207 #define MHD_INVALID_SOCKET (-1)
    208 #else /* !defined(_WIN32) || defined(_SYS_TYPES_FD_SET) */
    209 #define MHD_WINSOCK_SOCKETS 1
    210 #include <winsock2.h>
    211 typedef SOCKET MHD_socket;
    212 #define MHD_INVALID_SOCKET (INVALID_SOCKET)
    213 #endif /* !defined(_WIN32) || defined(_SYS_TYPES_FD_SET) */
    214 #define MHD_SOCKET_DEFINED 1
    215 #endif /* MHD_SOCKET_DEFINED */
    216 
    217 /**
    218  * Define MHD_NO_DEPRECATION before including "microhttpd.h" to disable deprecation messages
    219  */
    220 #ifdef MHD_NO_DEPRECATION
    221 #define _MHD_DEPR_MACRO(msg)
    222 #define _MHD_NO_DEPR_IN_MACRO 1
    223 #define _MHD_DEPR_IN_MACRO(msg)
    224 #define _MHD_NO_DEPR_FUNC 1
    225 #define _MHD_DEPR_FUNC(msg)
    226 #endif /* MHD_NO_DEPRECATION */
    227 
    228 #ifndef _MHD_DEPR_MACRO
    229 #if defined(_MSC_FULL_VER) && _MSC_VER + 0 >= 1500
    230 /* VS 2008 or later */
    231 /* Stringify macros */
    232 #define _MHD_INSTRMACRO(a) #a
    233 #define _MHD_STRMACRO(a) _MHD_INSTRMACRO (a)
    234 /* deprecation message */
    235 #define _MHD_DEPR_MACRO(msg) \
    236         __pragma \
    237         (message (__FILE__ "(" _MHD_STRMACRO ( __LINE__) "): warning: " msg))
    238 #define _MHD_DEPR_IN_MACRO(msg) _MHD_DEPR_MACRO (msg)
    239 #elif defined(__clang__) || defined(__GNUC_PATCHLEVEL__)
    240 /* clang or GCC since 3.0 */
    241 #define _MHD_GCC_PRAG(x) _Pragma(#x)
    242 #if (defined(__clang__) && \
    243   (__clang_major__ + 0 >= 5 || \
    244    (! defined(__apple_build_version__) && \
    245   (__clang_major__ + 0  > 3 || \
    246    (__clang_major__ + 0 == 3 && __clang_minor__ >=  3))))) || \
    247   __GNUC__ + 0 > 4 || (__GNUC__ + 0 == 4 && __GNUC_MINOR__ + 0 >= 8)
    248 /* clang >= 3.3 (or XCode's clang >= 5.0) or
    249    GCC >= 4.8 */
    250 #define _MHD_DEPR_MACRO(msg) _MHD_GCC_PRAG (GCC warning msg)
    251 #define _MHD_DEPR_IN_MACRO(msg) _MHD_DEPR_MACRO (msg)
    252 #else /* older clang or GCC */
    253 /* clang < 3.3, XCode's clang < 5.0, 3.0 <= GCC < 4.8 */
    254 #define _MHD_DEPR_MACRO(msg) _MHD_GCC_PRAG (message msg)
    255 #if (defined(__clang__) && \
    256   (__clang_major__ + 0  > 2 || \
    257    (__clang_major__ + 0 == 2 && __clang_minor__ >= 9)))  /* clang >= 2.9 */
    258 /* clang handles inline pragmas better than GCC */
    259 #define _MHD_DEPR_IN_MACRO(msg) _MHD_DEPR_MACRO (msg)
    260 #endif /* clang >= 2.9 */
    261 #endif  /* older clang or GCC */
    262 /* #elif defined(SOMEMACRO) */ /* add compiler-specific macros here if required */
    263 #endif /* clang || GCC >= 3.0 */
    264 #endif /* !_MHD_DEPR_MACRO */
    265 
    266 #ifndef _MHD_DEPR_MACRO
    267 #define _MHD_DEPR_MACRO(msg)
    268 #endif /* !_MHD_DEPR_MACRO */
    269 
    270 #ifndef _MHD_DEPR_IN_MACRO
    271 #define _MHD_NO_DEPR_IN_MACRO 1
    272 #define _MHD_DEPR_IN_MACRO(msg)
    273 #endif /* !_MHD_DEPR_IN_MACRO */
    274 
    275 #ifndef _MHD_DEPR_FUNC
    276 #if defined(_MSC_FULL_VER) && _MSC_VER + 0 >= 1400
    277 /* VS 2005 or later */
    278 #define _MHD_DEPR_FUNC(msg) __declspec(deprecated (msg))
    279 #elif defined(_MSC_FULL_VER) && _MSC_VER + 0 >= 1310
    280 /* VS .NET 2003 deprecation does not support custom messages */
    281 #define _MHD_DEPR_FUNC(msg) __declspec(deprecated)
    282 #elif (__GNUC__ + 0 >= 5) || (defined(__clang__) && \
    283   (__clang_major__ + 0 > 2 || \
    284    (__clang_major__ + 0 == 2 && __clang_minor__ >=  9)))
    285 /* GCC >= 5.0 or clang >= 2.9 */
    286 #define _MHD_DEPR_FUNC(msg) __attribute__((deprecated (msg)))
    287 #elif defined(__clang__) || __GNUC__ + 0 > 3 || \
    288   (__GNUC__ + 0 == 3 && __GNUC_MINOR__ + 0 >= 1)
    289 /* 3.1 <= GCC < 5.0 or clang < 2.9 */
    290 /* old GCC-style deprecation does not support custom messages */
    291 #define _MHD_DEPR_FUNC(msg) __attribute__((__deprecated__))
    292 /* #elif defined(SOMEMACRO) */ /* add compiler-specific macros here if required */
    293 #endif /* clang < 2.9 || GCC >= 3.1 */
    294 #endif /* !_MHD_DEPR_FUNC */
    295 
    296 #ifndef _MHD_DEPR_FUNC
    297 #define _MHD_NO_DEPR_FUNC 1
    298 #define _MHD_DEPR_FUNC(msg)
    299 #endif /* !_MHD_DEPR_FUNC */
    300 
    301 /**
    302  * Not all architectures and `printf()`'s support the `long long` type.
    303  * This gives the ability to replace `long long` with just a `long`,
    304  * standard `int` or a `short`.
    305  */
    306 #ifndef MHD_LONG_LONG
    307 /**
    308  * @deprecated use #MHD_UNSIGNED_LONG_LONG instead!
    309  */
    310 #define MHD_LONG_LONG long long
    311 #define MHD_UNSIGNED_LONG_LONG unsigned long long
    312 #else /* MHD_LONG_LONG */
    313 _MHD_DEPR_MACRO ( \
    314   "Macro MHD_LONG_LONG is deprecated, use MHD_UNSIGNED_LONG_LONG")
    315 #endif
    316 /**
    317  * Format string for printing a variable of type #MHD_LONG_LONG.
    318  * You should only redefine this if you also define #MHD_LONG_LONG.
    319  */
    320 #ifndef MHD_LONG_LONG_PRINTF
    321 /**
    322  * @deprecated use #MHD_UNSIGNED_LONG_LONG_PRINTF instead!
    323  */
    324 #define MHD_LONG_LONG_PRINTF "ll"
    325 #define MHD_UNSIGNED_LONG_LONG_PRINTF "%llu"
    326 #else /* MHD_LONG_LONG_PRINTF */
    327 _MHD_DEPR_MACRO ( \
    328   "Macro MHD_LONG_LONG_PRINTF is deprecated, use MHD_UNSIGNED_LONG_LONG_PRINTF")
    329 #endif
    330 
    331 
    332 /**
    333  * @defgroup httpcode HTTP response codes.
    334  * These are the status codes defined for HTTP responses.
    335  * See: https://www.iana.org/assignments/http-status-codes/http-status-codes.xhtml
    336  * Registry export date: 2023-09-29
    337  * @{
    338  */
    339 
    340 /* 100 "Continue".            RFC9110, Section 15.2.1. */
    341 #define MHD_HTTP_CONTINUE                    100
    342 /* 101 "Switching Protocols". RFC9110, Section 15.2.2. */
    343 #define MHD_HTTP_SWITCHING_PROTOCOLS         101
    344 /* 102 "Processing".          RFC2518. */
    345 #define MHD_HTTP_PROCESSING                  102
    346 /* 103 "Early Hints".         RFC8297. */
    347 #define MHD_HTTP_EARLY_HINTS                 103
    348 
    349 /* 200 "OK".                  RFC9110, Section 15.3.1. */
    350 #define MHD_HTTP_OK                          200
    351 /* 201 "Created".             RFC9110, Section 15.3.2. */
    352 #define MHD_HTTP_CREATED                     201
    353 /* 202 "Accepted".            RFC9110, Section 15.3.3. */
    354 #define MHD_HTTP_ACCEPTED                    202
    355 /* 203 "Non-Authoritative Information". RFC9110, Section 15.3.4. */
    356 #define MHD_HTTP_NON_AUTHORITATIVE_INFORMATION 203
    357 /* 204 "No Content".          RFC9110, Section 15.3.5. */
    358 #define MHD_HTTP_NO_CONTENT                  204
    359 /* 205 "Reset Content".       RFC9110, Section 15.3.6. */
    360 #define MHD_HTTP_RESET_CONTENT               205
    361 /* 206 "Partial Content".     RFC9110, Section 15.3.7. */
    362 #define MHD_HTTP_PARTIAL_CONTENT             206
    363 /* 207 "Multi-Status".        RFC4918. */
    364 #define MHD_HTTP_MULTI_STATUS                207
    365 /* 208 "Already Reported".    RFC5842. */
    366 #define MHD_HTTP_ALREADY_REPORTED            208
    367 
    368 /* 226 "IM Used".             RFC3229. */
    369 #define MHD_HTTP_IM_USED                     226
    370 
    371 /* 300 "Multiple Choices".    RFC9110, Section 15.4.1. */
    372 #define MHD_HTTP_MULTIPLE_CHOICES            300
    373 /* 301 "Moved Permanently".   RFC9110, Section 15.4.2. */
    374 #define MHD_HTTP_MOVED_PERMANENTLY           301
    375 /* 302 "Found".               RFC9110, Section 15.4.3. */
    376 #define MHD_HTTP_FOUND                       302
    377 /* 303 "See Other".           RFC9110, Section 15.4.4. */
    378 #define MHD_HTTP_SEE_OTHER                   303
    379 /* 304 "Not Modified".        RFC9110, Section 15.4.5. */
    380 #define MHD_HTTP_NOT_MODIFIED                304
    381 /* 305 "Use Proxy".           RFC9110, Section 15.4.6. */
    382 #define MHD_HTTP_USE_PROXY                   305
    383 /* 306 "Switch Proxy".        Not used! RFC9110, Section 15.4.7. */
    384 #define MHD_HTTP_SWITCH_PROXY                306
    385 /* 307 "Temporary Redirect".  RFC9110, Section 15.4.8. */
    386 #define MHD_HTTP_TEMPORARY_REDIRECT          307
    387 /* 308 "Permanent Redirect".  RFC9110, Section 15.4.9. */
    388 #define MHD_HTTP_PERMANENT_REDIRECT          308
    389 
    390 /* 400 "Bad Request".         RFC9110, Section 15.5.1. */
    391 #define MHD_HTTP_BAD_REQUEST                 400
    392 /* 401 "Unauthorized".        RFC9110, Section 15.5.2. */
    393 #define MHD_HTTP_UNAUTHORIZED                401
    394 /* 402 "Payment Required".    RFC9110, Section 15.5.3. */
    395 #define MHD_HTTP_PAYMENT_REQUIRED            402
    396 /* 403 "Forbidden".           RFC9110, Section 15.5.4. */
    397 #define MHD_HTTP_FORBIDDEN                   403
    398 /* 404 "Not Found".           RFC9110, Section 15.5.5. */
    399 #define MHD_HTTP_NOT_FOUND                   404
    400 /* 405 "Method Not Allowed".  RFC9110, Section 15.5.6. */
    401 #define MHD_HTTP_METHOD_NOT_ALLOWED          405
    402 /* 406 "Not Acceptable".      RFC9110, Section 15.5.7. */
    403 #define MHD_HTTP_NOT_ACCEPTABLE              406
    404 /* 407 "Proxy Authentication Required". RFC9110, Section 15.5.8. */
    405 #define MHD_HTTP_PROXY_AUTHENTICATION_REQUIRED 407
    406 /* 408 "Request Timeout".     RFC9110, Section 15.5.9. */
    407 #define MHD_HTTP_REQUEST_TIMEOUT             408
    408 /* 409 "Conflict".            RFC9110, Section 15.5.10. */
    409 #define MHD_HTTP_CONFLICT                    409
    410 /* 410 "Gone".                RFC9110, Section 15.5.11. */
    411 #define MHD_HTTP_GONE                        410
    412 /* 411 "Length Required".     RFC9110, Section 15.5.12. */
    413 #define MHD_HTTP_LENGTH_REQUIRED             411
    414 /* 412 "Precondition Failed". RFC9110, Section 15.5.13. */
    415 #define MHD_HTTP_PRECONDITION_FAILED         412
    416 /* 413 "Content Too Large".   RFC9110, Section 15.5.14. */
    417 #define MHD_HTTP_CONTENT_TOO_LARGE           413
    418 /* 414 "URI Too Long".        RFC9110, Section 15.5.15. */
    419 #define MHD_HTTP_URI_TOO_LONG                414
    420 /* 415 "Unsupported Media Type". RFC9110, Section 15.5.16. */
    421 #define MHD_HTTP_UNSUPPORTED_MEDIA_TYPE      415
    422 /* 416 "Range Not Satisfiable". RFC9110, Section 15.5.17. */
    423 #define MHD_HTTP_RANGE_NOT_SATISFIABLE       416
    424 /* 417 "Expectation Failed".  RFC9110, Section 15.5.18. */
    425 #define MHD_HTTP_EXPECTATION_FAILED          417
    426 
    427 
    428 /* 421 "Misdirected Request". RFC9110, Section 15.5.20. */
    429 #define MHD_HTTP_MISDIRECTED_REQUEST         421
    430 /* 422 "Unprocessable Content". RFC9110, Section 15.5.21. */
    431 #define MHD_HTTP_UNPROCESSABLE_CONTENT       422
    432 /* 423 "Locked".              RFC4918. */
    433 #define MHD_HTTP_LOCKED                      423
    434 /* 424 "Failed Dependency".   RFC4918. */
    435 #define MHD_HTTP_FAILED_DEPENDENCY           424
    436 /* 425 "Too Early".           RFC8470. */
    437 #define MHD_HTTP_TOO_EARLY                   425
    438 /* 426 "Upgrade Required".    RFC9110, Section 15.5.22. */
    439 #define MHD_HTTP_UPGRADE_REQUIRED            426
    440 
    441 /* 428 "Precondition Required". RFC6585. */
    442 #define MHD_HTTP_PRECONDITION_REQUIRED       428
    443 /* 429 "Too Many Requests".   RFC6585. */
    444 #define MHD_HTTP_TOO_MANY_REQUESTS           429
    445 
    446 /* 431 "Request Header Fields Too Large". RFC6585. */
    447 #define MHD_HTTP_REQUEST_HEADER_FIELDS_TOO_LARGE 431
    448 
    449 /* 451 "Unavailable For Legal Reasons". RFC7725. */
    450 #define MHD_HTTP_UNAVAILABLE_FOR_LEGAL_REASONS 451
    451 
    452 /* 500 "Internal Server Error". RFC9110, Section 15.6.1. */
    453 #define MHD_HTTP_INTERNAL_SERVER_ERROR       500
    454 /* 501 "Not Implemented".     RFC9110, Section 15.6.2. */
    455 #define MHD_HTTP_NOT_IMPLEMENTED             501
    456 /* 502 "Bad Gateway".         RFC9110, Section 15.6.3. */
    457 #define MHD_HTTP_BAD_GATEWAY                 502
    458 /* 503 "Service Unavailable". RFC9110, Section 15.6.4. */
    459 #define MHD_HTTP_SERVICE_UNAVAILABLE         503
    460 /* 504 "Gateway Timeout".     RFC9110, Section 15.6.5. */
    461 #define MHD_HTTP_GATEWAY_TIMEOUT             504
    462 /* 505 "HTTP Version Not Supported". RFC9110, Section 15.6.6. */
    463 #define MHD_HTTP_HTTP_VERSION_NOT_SUPPORTED  505
    464 /* 506 "Variant Also Negotiates". RFC2295. */
    465 #define MHD_HTTP_VARIANT_ALSO_NEGOTIATES     506
    466 /* 507 "Insufficient Storage". RFC4918. */
    467 #define MHD_HTTP_INSUFFICIENT_STORAGE        507
    468 /* 508 "Loop Detected".       RFC5842. */
    469 #define MHD_HTTP_LOOP_DETECTED               508
    470 
    471 /* 510 "Not Extended".        (OBSOLETED) RFC2774; status-change-http-experiments-to-historic. */
    472 #define MHD_HTTP_NOT_EXTENDED                510
    473 /* 511 "Network Authentication Required". RFC6585. */
    474 #define MHD_HTTP_NETWORK_AUTHENTICATION_REQUIRED 511
    475 
    476 
    477 /* Not registered non-standard codes */
    478 /* 449 "Reply With".          MS IIS extension. */
    479 #define MHD_HTTP_RETRY_WITH                  449
    480 
    481 /* 450 "Blocked by Windows Parental Controls". MS extension. */
    482 #define MHD_HTTP_BLOCKED_BY_WINDOWS_PARENTAL_CONTROLS 450
    483 
    484 /* 509 "Bandwidth Limit Exceeded". Apache extension. */
    485 #define MHD_HTTP_BANDWIDTH_LIMIT_EXCEEDED    509
    486 
    487 /* Deprecated names and codes */
    488 /** @deprecated */
    489 #define MHD_HTTP_METHOD_NOT_ACCEPTABLE _MHD_DEPR_IN_MACRO ( \
    490           "Value MHD_HTTP_METHOD_NOT_ACCEPTABLE is deprecated, use MHD_HTTP_NOT_ACCEPTABLE" \
    491           ) 406
    492 
    493 /** @deprecated */
    494 #define MHD_HTTP_REQUEST_ENTITY_TOO_LARGE _MHD_DEPR_IN_MACRO ( \
    495           "Value MHD_HTTP_REQUEST_ENTITY_TOO_LARGE is deprecated, use MHD_HTTP_CONTENT_TOO_LARGE" \
    496           ) 413
    497 
    498 /** @deprecated */
    499 #define MHD_HTTP_PAYLOAD_TOO_LARGE _MHD_DEPR_IN_MACRO ( \
    500           "Value MHD_HTTP_PAYLOAD_TOO_LARGE is deprecated use MHD_HTTP_CONTENT_TOO_LARGE" \
    501           ) 413
    502 
    503 /** @deprecated */
    504 #define MHD_HTTP_REQUEST_URI_TOO_LONG _MHD_DEPR_IN_MACRO ( \
    505           "Value MHD_HTTP_REQUEST_URI_TOO_LONG is deprecated, use MHD_HTTP_URI_TOO_LONG" \
    506           ) 414
    507 
    508 /** @deprecated */
    509 #define MHD_HTTP_REQUESTED_RANGE_NOT_SATISFIABLE _MHD_DEPR_IN_MACRO ( \
    510           "Value MHD_HTTP_REQUESTED_RANGE_NOT_SATISFIABLE is deprecated, use MHD_HTTP_RANGE_NOT_SATISFIABLE" \
    511           ) 416
    512 
    513 /** @deprecated */
    514 #define MHD_HTTP_UNPROCESSABLE_ENTITY _MHD_DEPR_IN_MACRO ( \
    515           "Value MHD_HTTP_UNPROCESSABLE_ENTITY is deprecated, use MHD_HTTP_UNPROCESSABLE_CONTENT" \
    516           ) 422
    517 
    518 /** @deprecated */
    519 #define MHD_HTTP_UNORDERED_COLLECTION _MHD_DEPR_IN_MACRO ( \
    520           "Value MHD_HTTP_UNORDERED_COLLECTION is deprecated as it was removed from RFC" \
    521           ) 425
    522 
    523 /** @deprecated */
    524 #define MHD_HTTP_NO_RESPONSE _MHD_DEPR_IN_MACRO ( \
    525           "Value MHD_HTTP_NO_RESPONSE is deprecated as it is nginx internal code for logs only" \
    526           ) 444
    527 
    528 
    529 /** @} */ /* end of group httpcode */
    530 
    531 /**
    532  * Returns the string reason phrase for a response code.
    533  *
    534  * If message string is not available for a status code,
    535  * "Unknown" string will be returned.
    536  */
    537 _MHD_EXTERN const char *
    538 MHD_get_reason_phrase_for (unsigned int code);
    539 
    540 
    541 /**
    542  * Returns the length of the string reason phrase for a response code.
    543  *
    544  * If message string is not available for a status code,
    545  * 0 is returned.
    546  */
    547 _MHD_EXTERN size_t
    548 MHD_get_reason_phrase_len_for (unsigned int code);
    549 
    550 /**
    551  * Flag to be or-ed with MHD_HTTP status code for
    552  * SHOUTcast.  This will cause the response to begin
    553  * with the SHOUTcast "ICY" line instead of "HTTP/1.x".
    554  * @ingroup specialized
    555  */
    556 #define MHD_ICY_FLAG ((uint32_t) (((uint32_t) 1) << 31))
    557 
    558 /**
    559  * @defgroup headers HTTP headers
    560  * The standard headers found in HTTP requests and responses.
    561  * See: https://www.iana.org/assignments/http-fields/http-fields.xhtml
    562  * Registry export date: 2023-10-02
    563  * @{
    564  */
    565 
    566 /* Main HTTP headers. */
    567 /* Permanent.     RFC9110, Section 12.5.1: HTTP Semantics */
    568 #define MHD_HTTP_HEADER_ACCEPT       "Accept"
    569 /* Deprecated.    RFC9110, Section 12.5.2: HTTP Semantics */
    570 #define MHD_HTTP_HEADER_ACCEPT_CHARSET "Accept-Charset"
    571 /* Permanent.     RFC9110, Section 12.5.3: HTTP Semantics */
    572 #define MHD_HTTP_HEADER_ACCEPT_ENCODING "Accept-Encoding"
    573 /* Permanent.     RFC9110, Section 12.5.4: HTTP Semantics */
    574 #define MHD_HTTP_HEADER_ACCEPT_LANGUAGE "Accept-Language"
    575 /* Permanent.     RFC9110, Section 14.3: HTTP Semantics */
    576 #define MHD_HTTP_HEADER_ACCEPT_RANGES "Accept-Ranges"
    577 /* Permanent.     RFC9111, Section 5.1: HTTP Caching */
    578 #define MHD_HTTP_HEADER_AGE          "Age"
    579 /* Permanent.     RFC9110, Section 10.2.1: HTTP Semantics */
    580 #define MHD_HTTP_HEADER_ALLOW        "Allow"
    581 /* Permanent.     RFC9110, Section 11.6.3: HTTP Semantics */
    582 #define MHD_HTTP_HEADER_AUTHENTICATION_INFO "Authentication-Info"
    583 /* Permanent.     RFC9110, Section 11.6.2: HTTP Semantics */
    584 #define MHD_HTTP_HEADER_AUTHORIZATION "Authorization"
    585 /* Permanent.     RFC9111, Section 5.2 */
    586 #define MHD_HTTP_HEADER_CACHE_CONTROL "Cache-Control"
    587 /* Permanent.     RFC9112, Section 9.6: HTTP/1.1 */
    588 #define MHD_HTTP_HEADER_CLOSE        "Close"
    589 /* Permanent.     RFC9110, Section 7.6.1: HTTP Semantics */
    590 #define MHD_HTTP_HEADER_CONNECTION   "Connection"
    591 /* Permanent.     RFC9110, Section 8.4: HTTP Semantics */
    592 #define MHD_HTTP_HEADER_CONTENT_ENCODING "Content-Encoding"
    593 /* Permanent.     RFC9110, Section 8.5: HTTP Semantics */
    594 #define MHD_HTTP_HEADER_CONTENT_LANGUAGE "Content-Language"
    595 /* Permanent.     RFC9110, Section 8.6: HTTP Semantics */
    596 #define MHD_HTTP_HEADER_CONTENT_LENGTH "Content-Length"
    597 /* Permanent.     RFC9110, Section 8.7: HTTP Semantics */
    598 #define MHD_HTTP_HEADER_CONTENT_LOCATION "Content-Location"
    599 /* Permanent.     RFC9110, Section 14.4: HTTP Semantics */
    600 #define MHD_HTTP_HEADER_CONTENT_RANGE "Content-Range"
    601 /* Permanent.     RFC9110, Section 8.3: HTTP Semantics */
    602 #define MHD_HTTP_HEADER_CONTENT_TYPE "Content-Type"
    603 /* Permanent.     RFC9110, Section 6.6.1: HTTP Semantics */
    604 #define MHD_HTTP_HEADER_DATE         "Date"
    605 /* Permanent.     RFC9110, Section 8.8.3: HTTP Semantics */
    606 #define MHD_HTTP_HEADER_ETAG         "ETag"
    607 /* Permanent.     RFC9110, Section 10.1.1: HTTP Semantics */
    608 #define MHD_HTTP_HEADER_EXPECT       "Expect"
    609 /* Permanent.     RFC9111, Section 5.3: HTTP Caching */
    610 #define MHD_HTTP_HEADER_EXPIRES      "Expires"
    611 /* Permanent.     RFC9110, Section 10.1.2: HTTP Semantics */
    612 #define MHD_HTTP_HEADER_FROM         "From"
    613 /* Permanent.     RFC9110, Section 7.2: HTTP Semantics */
    614 #define MHD_HTTP_HEADER_HOST         "Host"
    615 /* Permanent.     RFC9110, Section 13.1.1: HTTP Semantics */
    616 #define MHD_HTTP_HEADER_IF_MATCH     "If-Match"
    617 /* Permanent.     RFC9110, Section 13.1.3: HTTP Semantics */
    618 #define MHD_HTTP_HEADER_IF_MODIFIED_SINCE "If-Modified-Since"
    619 /* Permanent.     RFC9110, Section 13.1.2: HTTP Semantics */
    620 #define MHD_HTTP_HEADER_IF_NONE_MATCH "If-None-Match"
    621 /* Permanent.     RFC9110, Section 13.1.5: HTTP Semantics */
    622 #define MHD_HTTP_HEADER_IF_RANGE     "If-Range"
    623 /* Permanent.     RFC9110, Section 13.1.4: HTTP Semantics */
    624 #define MHD_HTTP_HEADER_IF_UNMODIFIED_SINCE "If-Unmodified-Since"
    625 /* Permanent.     RFC9110, Section 8.8.2: HTTP Semantics */
    626 #define MHD_HTTP_HEADER_LAST_MODIFIED "Last-Modified"
    627 /* Permanent.     RFC9110, Section 10.2.2: HTTP Semantics */
    628 #define MHD_HTTP_HEADER_LOCATION     "Location"
    629 /* Permanent.     RFC9110, Section 7.6.2: HTTP Semantics */
    630 #define MHD_HTTP_HEADER_MAX_FORWARDS "Max-Forwards"
    631 /* Permanent.     RFC9112, Appendix B.1: HTTP/1.1 */
    632 #define MHD_HTTP_HEADER_MIME_VERSION "MIME-Version"
    633 /* Deprecated.    RFC9111, Section 5.4: HTTP Caching */
    634 #define MHD_HTTP_HEADER_PRAGMA       "Pragma"
    635 /* Permanent.     RFC9110, Section 11.7.1: HTTP Semantics */
    636 #define MHD_HTTP_HEADER_PROXY_AUTHENTICATE "Proxy-Authenticate"
    637 /* Permanent.     RFC9110, Section 11.7.3: HTTP Semantics */
    638 #define MHD_HTTP_HEADER_PROXY_AUTHENTICATION_INFO "Proxy-Authentication-Info"
    639 /* Permanent.     RFC9110, Section 11.7.2: HTTP Semantics */
    640 #define MHD_HTTP_HEADER_PROXY_AUTHORIZATION "Proxy-Authorization"
    641 /* Permanent.     RFC9110, Section 14.2: HTTP Semantics */
    642 #define MHD_HTTP_HEADER_RANGE        "Range"
    643 /* Permanent.     RFC9110, Section 10.1.3: HTTP Semantics */
    644 #define MHD_HTTP_HEADER_REFERER      "Referer"
    645 /* Permanent.     RFC9110, Section 10.2.3: HTTP Semantics */
    646 #define MHD_HTTP_HEADER_RETRY_AFTER  "Retry-After"
    647 /* Permanent.     RFC9110, Section 10.2.4: HTTP Semantics */
    648 #define MHD_HTTP_HEADER_SERVER       "Server"
    649 /* Permanent.     RFC9110, Section 10.1.4: HTTP Semantics */
    650 #define MHD_HTTP_HEADER_TE           "TE"
    651 /* Permanent.     RFC9110, Section 6.6.2: HTTP Semantics */
    652 #define MHD_HTTP_HEADER_TRAILER      "Trailer"
    653 /* Permanent.     RFC9112, Section 6.1: HTTP Semantics */
    654 #define MHD_HTTP_HEADER_TRANSFER_ENCODING "Transfer-Encoding"
    655 /* Permanent.     RFC9110, Section 7.8: HTTP Semantics */
    656 #define MHD_HTTP_HEADER_UPGRADE      "Upgrade"
    657 /* Permanent.     RFC9110, Section 10.1.5: HTTP Semantics */
    658 #define MHD_HTTP_HEADER_USER_AGENT   "User-Agent"
    659 /* Permanent.     RFC9110, Section 12.5.5: HTTP Semantics */
    660 #define MHD_HTTP_HEADER_VARY         "Vary"
    661 /* Permanent.     RFC9110, Section 7.6.3: HTTP Semantics */
    662 #define MHD_HTTP_HEADER_VIA          "Via"
    663 /* Permanent.     RFC9110, Section 11.6.1: HTTP Semantics */
    664 #define MHD_HTTP_HEADER_WWW_AUTHENTICATE "WWW-Authenticate"
    665 /* Permanent.     RFC9110, Section 12.5.5: HTTP Semantics */
    666 #define MHD_HTTP_HEADER_ASTERISK     "*"
    667 
    668 /* Additional HTTP headers. */
    669 /* Permanent.     RFC 3229: Delta encoding in HTTP */
    670 #define MHD_HTTP_HEADER_A_IM         "A-IM"
    671 /* Permanent.     RFC 2324: Hyper Text Coffee Pot Control Protocol (HTCPCP/1.0) */
    672 #define MHD_HTTP_HEADER_ACCEPT_ADDITIONS "Accept-Additions"
    673 /* Permanent.     RFC 8942, Section 3.1: HTTP Client Hints */
    674 #define MHD_HTTP_HEADER_ACCEPT_CH    "Accept-CH"
    675 /* Permanent.     RFC 7089: HTTP Framework for Time-Based Access to Resource States -- Memento */
    676 #define MHD_HTTP_HEADER_ACCEPT_DATETIME "Accept-Datetime"
    677 /* Permanent.     RFC 2295: Transparent Content Negotiation in HTTP */
    678 #define MHD_HTTP_HEADER_ACCEPT_FEATURES "Accept-Features"
    679 /* Permanent.     RFC 5789: PATCH Method for HTTP */
    680 #define MHD_HTTP_HEADER_ACCEPT_PATCH "Accept-Patch"
    681 /* Permanent.     Linked Data Platform 1.0 */
    682 #define MHD_HTTP_HEADER_ACCEPT_POST  "Accept-Post"
    683 /* Permanent.     RFC-ietf-httpbis-message-signatures-19, Section 5.1: HTTP Message Signatures */
    684 #define MHD_HTTP_HEADER_ACCEPT_SIGNATURE "Accept-Signature"
    685 /* Permanent.     Fetch */
    686 #define MHD_HTTP_HEADER_ACCESS_CONTROL_ALLOW_CREDENTIALS \
    687         "Access-Control-Allow-Credentials"
    688 /* Permanent.     Fetch */
    689 #define MHD_HTTP_HEADER_ACCESS_CONTROL_ALLOW_HEADERS \
    690         "Access-Control-Allow-Headers"
    691 /* Permanent.     Fetch */
    692 #define MHD_HTTP_HEADER_ACCESS_CONTROL_ALLOW_METHODS \
    693         "Access-Control-Allow-Methods"
    694 /* Permanent.     Fetch */
    695 #define MHD_HTTP_HEADER_ACCESS_CONTROL_ALLOW_ORIGIN \
    696         "Access-Control-Allow-Origin"
    697 /* Permanent.     Fetch */
    698 #define MHD_HTTP_HEADER_ACCESS_CONTROL_EXPOSE_HEADERS \
    699         "Access-Control-Expose-Headers"
    700 /* Permanent.     Fetch */
    701 #define MHD_HTTP_HEADER_ACCESS_CONTROL_MAX_AGE "Access-Control-Max-Age"
    702 /* Permanent.     Fetch */
    703 #define MHD_HTTP_HEADER_ACCESS_CONTROL_REQUEST_HEADERS \
    704         "Access-Control-Request-Headers"
    705 /* Permanent.     Fetch */
    706 #define MHD_HTTP_HEADER_ACCESS_CONTROL_REQUEST_METHOD \
    707         "Access-Control-Request-Method"
    708 /* Permanent.     RFC 7639, Section 2: The ALPN HTTP Header Field */
    709 #define MHD_HTTP_HEADER_ALPN         "ALPN"
    710 /* Permanent.     RFC 7838: HTTP Alternative Services */
    711 #define MHD_HTTP_HEADER_ALT_SVC      "Alt-Svc"
    712 /* Permanent.     RFC 7838: HTTP Alternative Services */
    713 #define MHD_HTTP_HEADER_ALT_USED     "Alt-Used"
    714 /* Permanent.     RFC 2295: Transparent Content Negotiation in HTTP */
    715 #define MHD_HTTP_HEADER_ALTERNATES   "Alternates"
    716 /* Permanent.     RFC 4437: Web Distributed Authoring and Versioning (WebDAV) Redirect Reference Resources */
    717 #define MHD_HTTP_HEADER_APPLY_TO_REDIRECT_REF "Apply-To-Redirect-Ref"
    718 /* Permanent.     RFC 8053, Section 4: HTTP Authentication Extensions for Interactive Clients */
    719 #define MHD_HTTP_HEADER_AUTHENTICATION_CONTROL "Authentication-Control"
    720 /* Permanent.     RFC9211: The Cache-Status HTTP Response Header Field */
    721 #define MHD_HTTP_HEADER_CACHE_STATUS "Cache-Status"
    722 /* Permanent.     RFC 8607, Section 5.1: Calendaring Extensions to WebDAV (CalDAV): Managed Attachments */
    723 #define MHD_HTTP_HEADER_CAL_MANAGED_ID "Cal-Managed-ID"
    724 /* Permanent.     RFC 7809, Section 7.1: Calendaring Extensions to WebDAV (CalDAV): Time Zones by Reference */
    725 #define MHD_HTTP_HEADER_CALDAV_TIMEZONES "CalDAV-Timezones"
    726 /* Permanent.     RFC9297 */
    727 #define MHD_HTTP_HEADER_CAPSULE_PROTOCOL "Capsule-Protocol"
    728 /* Permanent.     RFC9213: Targeted HTTP Cache Control */
    729 #define MHD_HTTP_HEADER_CDN_CACHE_CONTROL "CDN-Cache-Control"
    730 /* Permanent.     RFC 8586: Loop Detection in Content Delivery Networks (CDNs) */
    731 #define MHD_HTTP_HEADER_CDN_LOOP     "CDN-Loop"
    732 /* Permanent.     RFC 8739, Section 3.3: Support for Short-Term, Automatically Renewed (STAR) Certificates in the Automated Certificate Management Environment (ACME) */
    733 #define MHD_HTTP_HEADER_CERT_NOT_AFTER "Cert-Not-After"
    734 /* Permanent.     RFC 8739, Section 3.3: Support for Short-Term, Automatically Renewed (STAR) Certificates in the Automated Certificate Management Environment (ACME) */
    735 #define MHD_HTTP_HEADER_CERT_NOT_BEFORE "Cert-Not-Before"
    736 /* Permanent.     Clear Site Data */
    737 #define MHD_HTTP_HEADER_CLEAR_SITE_DATA "Clear-Site-Data"
    738 /* Permanent.     RFC9440, Section 2: Client-Cert HTTP Header Field */
    739 #define MHD_HTTP_HEADER_CLIENT_CERT  "Client-Cert"
    740 /* Permanent.     RFC9440, Section 2: Client-Cert HTTP Header Field */
    741 #define MHD_HTTP_HEADER_CLIENT_CERT_CHAIN "Client-Cert-Chain"
    742 /* Permanent.     RFC-ietf-httpbis-digest-headers-13, Section 2: Digest Fields */
    743 #define MHD_HTTP_HEADER_CONTENT_DIGEST "Content-Digest"
    744 /* Permanent.     RFC 6266: Use of the Content-Disposition Header Field in the Hypertext Transfer Protocol (HTTP) */
    745 #define MHD_HTTP_HEADER_CONTENT_DISPOSITION "Content-Disposition"
    746 /* Permanent.     The HTTP Distribution and Replication Protocol */
    747 #define MHD_HTTP_HEADER_CONTENT_ID   "Content-ID"
    748 /* Permanent.     Content Security Policy Level 3 */
    749 #define MHD_HTTP_HEADER_CONTENT_SECURITY_POLICY "Content-Security-Policy"
    750 /* Permanent.     Content Security Policy Level 3 */
    751 #define MHD_HTTP_HEADER_CONTENT_SECURITY_POLICY_REPORT_ONLY \
    752         "Content-Security-Policy-Report-Only"
    753 /* Permanent.     RFC 6265: HTTP State Management Mechanism */
    754 #define MHD_HTTP_HEADER_COOKIE       "Cookie"
    755 /* Permanent.     HTML */
    756 #define MHD_HTTP_HEADER_CROSS_ORIGIN_EMBEDDER_POLICY \
    757         "Cross-Origin-Embedder-Policy"
    758 /* Permanent.     HTML */
    759 #define MHD_HTTP_HEADER_CROSS_ORIGIN_EMBEDDER_POLICY_REPORT_ONLY \
    760         "Cross-Origin-Embedder-Policy-Report-Only"
    761 /* Permanent.     HTML */
    762 #define MHD_HTTP_HEADER_CROSS_ORIGIN_OPENER_POLICY "Cross-Origin-Opener-Policy"
    763 /* Permanent.     HTML */
    764 #define MHD_HTTP_HEADER_CROSS_ORIGIN_OPENER_POLICY_REPORT_ONLY \
    765         "Cross-Origin-Opener-Policy-Report-Only"
    766 /* Permanent.     Fetch */
    767 #define MHD_HTTP_HEADER_CROSS_ORIGIN_RESOURCE_POLICY \
    768         "Cross-Origin-Resource-Policy"
    769 /* Permanent.     RFC 5323: Web Distributed Authoring and Versioning (WebDAV) SEARCH */
    770 #define MHD_HTTP_HEADER_DASL         "DASL"
    771 /* Permanent.     RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV) */
    772 #define MHD_HTTP_HEADER_DAV          "DAV"
    773 /* Permanent.     RFC 3229: Delta encoding in HTTP */
    774 #define MHD_HTTP_HEADER_DELTA_BASE   "Delta-Base"
    775 /* Permanent.     RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV) */
    776 #define MHD_HTTP_HEADER_DEPTH        "Depth"
    777 /* Permanent.     RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV) */
    778 #define MHD_HTTP_HEADER_DESTINATION  "Destination"
    779 /* Permanent.     The HTTP Distribution and Replication Protocol */
    780 #define MHD_HTTP_HEADER_DIFFERENTIAL_ID "Differential-ID"
    781 /* Permanent.     RFC9449: OAuth 2.0 Demonstrating Proof of Possession (DPoP) */
    782 #define MHD_HTTP_HEADER_DPOP         "DPoP"
    783 /* Permanent.     RFC9449: OAuth 2.0 Demonstrating Proof of Possession (DPoP) */
    784 #define MHD_HTTP_HEADER_DPOP_NONCE   "DPoP-Nonce"
    785 /* Permanent.     RFC 8470: Using Early Data in HTTP */
    786 #define MHD_HTTP_HEADER_EARLY_DATA   "Early-Data"
    787 /* Permanent.     RFC9163: Expect-CT Extension for HTTP */
    788 #define MHD_HTTP_HEADER_EXPECT_CT    "Expect-CT"
    789 /* Permanent.     RFC 7239: Forwarded HTTP Extension */
    790 #define MHD_HTTP_HEADER_FORWARDED    "Forwarded"
    791 /* Permanent.     RFC 7486, Section 6.1.1: HTTP Origin-Bound Authentication (HOBA) */
    792 #define MHD_HTTP_HEADER_HOBAREG      "Hobareg"
    793 /* Permanent.     RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV) */
    794 #define MHD_HTTP_HEADER_IF           "If"
    795 /* Permanent.      RFC 6338: Scheduling Extensions to CalDAV */
    796 #define MHD_HTTP_HEADER_IF_SCHEDULE_TAG_MATCH "If-Schedule-Tag-Match"
    797 /* Permanent.     RFC 3229: Delta encoding in HTTP */
    798 #define MHD_HTTP_HEADER_IM           "IM"
    799 /* Permanent.     RFC 8473: Token Binding over HTTP */
    800 #define MHD_HTTP_HEADER_INCLUDE_REFERRED_TOKEN_BINDING_ID \
    801         "Include-Referred-Token-Binding-ID"
    802 /* Permanent.     RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1 */
    803 #define MHD_HTTP_HEADER_KEEP_ALIVE   "Keep-Alive"
    804 /* Permanent.     RFC 3253: Versioning Extensions to WebDAV: (Web Distributed Authoring and Versioning) */
    805 #define MHD_HTTP_HEADER_LABEL        "Label"
    806 /* Permanent.     HTML */
    807 #define MHD_HTTP_HEADER_LAST_EVENT_ID "Last-Event-ID"
    808 /* Permanent.     RFC 8288: Web Linking */
    809 #define MHD_HTTP_HEADER_LINK         "Link"
    810 /* Permanent.     RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV) */
    811 #define MHD_HTTP_HEADER_LOCK_TOKEN   "Lock-Token"
    812 /* Permanent.     RFC 7089: HTTP Framework for Time-Based Access to Resource States -- Memento */
    813 #define MHD_HTTP_HEADER_MEMENTO_DATETIME "Memento-Datetime"
    814 /* Permanent.     RFC 2227: Simple Hit-Metering and Usage-Limiting for HTTP */
    815 #define MHD_HTTP_HEADER_METER        "Meter"
    816 /* Permanent.     RFC 2295: Transparent Content Negotiation in HTTP */
    817 #define MHD_HTTP_HEADER_NEGOTIATE    "Negotiate"
    818 /* Permanent.     Network Error Logging */
    819 #define MHD_HTTP_HEADER_NEL          "NEL"
    820 /* Permanent.     OData Version 4.01 Part 1: Protocol; OASIS; Chet_Ensign */
    821 #define MHD_HTTP_HEADER_ODATA_ENTITYID "OData-EntityId"
    822 /* Permanent.     OData Version 4.01 Part 1: Protocol; OASIS; Chet_Ensign */
    823 #define MHD_HTTP_HEADER_ODATA_ISOLATION "OData-Isolation"
    824 /* Permanent.     OData Version 4.01 Part 1: Protocol; OASIS; Chet_Ensign */
    825 #define MHD_HTTP_HEADER_ODATA_MAXVERSION "OData-MaxVersion"
    826 /* Permanent.     OData Version 4.01 Part 1: Protocol; OASIS; Chet_Ensign */
    827 #define MHD_HTTP_HEADER_ODATA_VERSION "OData-Version"
    828 /* Permanent.     RFC 8053, Section 3: HTTP Authentication Extensions for Interactive Clients */
    829 #define MHD_HTTP_HEADER_OPTIONAL_WWW_AUTHENTICATE "Optional-WWW-Authenticate"
    830 /* Permanent.     RFC 3648: Web Distributed Authoring and Versioning (WebDAV) Ordered Collections Protocol */
    831 #define MHD_HTTP_HEADER_ORDERING_TYPE "Ordering-Type"
    832 /* Permanent.     RFC 6454: The Web Origin Concept */
    833 #define MHD_HTTP_HEADER_ORIGIN       "Origin"
    834 /* Permanent.     HTML */
    835 #define MHD_HTTP_HEADER_ORIGIN_AGENT_CLUSTER "Origin-Agent-Cluster"
    836 /* Permanent.     RFC 8613, Section 11.1: Object Security for Constrained RESTful Environments (OSCORE) */
    837 #define MHD_HTTP_HEADER_OSCORE       "OSCORE"
    838 /* Permanent.     OASIS Project Specification 01; OASIS; Chet_Ensign */
    839 #define MHD_HTTP_HEADER_OSLC_CORE_VERSION "OSLC-Core-Version"
    840 /* Permanent.     RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV) */
    841 #define MHD_HTTP_HEADER_OVERWRITE    "Overwrite"
    842 /* Permanent.     HTML */
    843 #define MHD_HTTP_HEADER_PING_FROM    "Ping-From"
    844 /* Permanent.     HTML */
    845 #define MHD_HTTP_HEADER_PING_TO      "Ping-To"
    846 /* Permanent.     RFC 3648: Web Distributed Authoring and Versioning (WebDAV) Ordered Collections Protocol */
    847 #define MHD_HTTP_HEADER_POSITION     "Position"
    848 /* Permanent.     RFC 7240: Prefer Header for HTTP */
    849 #define MHD_HTTP_HEADER_PREFER       "Prefer"
    850 /* Permanent.     RFC 7240: Prefer Header for HTTP */
    851 #define MHD_HTTP_HEADER_PREFERENCE_APPLIED "Preference-Applied"
    852 /* Permanent.     RFC9218: Extensible Prioritization Scheme for HTTP */
    853 #define MHD_HTTP_HEADER_PRIORITY     "Priority"
    854 /* Permanent.     RFC9209: The Proxy-Status HTTP Response Header Field */
    855 #define MHD_HTTP_HEADER_PROXY_STATUS "Proxy-Status"
    856 /* Permanent.     RFC 7469: Public Key Pinning Extension for HTTP */
    857 #define MHD_HTTP_HEADER_PUBLIC_KEY_PINS "Public-Key-Pins"
    858 /* Permanent.     RFC 7469: Public Key Pinning Extension for HTTP */
    859 #define MHD_HTTP_HEADER_PUBLIC_KEY_PINS_REPORT_ONLY \
    860         "Public-Key-Pins-Report-Only"
    861 /* Permanent.     RFC 4437: Web Distributed Authoring and Versioning (WebDAV) Redirect Reference Resources */
    862 #define MHD_HTTP_HEADER_REDIRECT_REF "Redirect-Ref"
    863 /* Permanent.     HTML */
    864 #define MHD_HTTP_HEADER_REFRESH      "Refresh"
    865 /* Permanent.     RFC 8555, Section 6.5.1: Automatic Certificate Management Environment (ACME) */
    866 #define MHD_HTTP_HEADER_REPLAY_NONCE "Replay-Nonce"
    867 /* Permanent.     RFC-ietf-httpbis-digest-headers-13, Section 3: Digest Fields */
    868 #define MHD_HTTP_HEADER_REPR_DIGEST  "Repr-Digest"
    869 /* Permanent.     RFC 6638: Scheduling Extensions to CalDAV */
    870 #define MHD_HTTP_HEADER_SCHEDULE_REPLY "Schedule-Reply"
    871 /* Permanent.     RFC 6338: Scheduling Extensions to CalDAV */
    872 #define MHD_HTTP_HEADER_SCHEDULE_TAG "Schedule-Tag"
    873 /* Permanent.     Fetch */
    874 #define MHD_HTTP_HEADER_SEC_PURPOSE  "Sec-Purpose"
    875 /* Permanent.     RFC 8473: Token Binding over HTTP */
    876 #define MHD_HTTP_HEADER_SEC_TOKEN_BINDING "Sec-Token-Binding"
    877 /* Permanent.     RFC 6455: The WebSocket Protocol */
    878 #define MHD_HTTP_HEADER_SEC_WEBSOCKET_ACCEPT "Sec-WebSocket-Accept"
    879 /* Permanent.     RFC 6455: The WebSocket Protocol */
    880 #define MHD_HTTP_HEADER_SEC_WEBSOCKET_EXTENSIONS "Sec-WebSocket-Extensions"
    881 /* Permanent.     RFC 6455: The WebSocket Protocol */
    882 #define MHD_HTTP_HEADER_SEC_WEBSOCKET_KEY "Sec-WebSocket-Key"
    883 /* Permanent.     RFC 6455: The WebSocket Protocol */
    884 #define MHD_HTTP_HEADER_SEC_WEBSOCKET_PROTOCOL "Sec-WebSocket-Protocol"
    885 /* Permanent.     RFC 6455: The WebSocket Protocol */
    886 #define MHD_HTTP_HEADER_SEC_WEBSOCKET_VERSION "Sec-WebSocket-Version"
    887 /* Permanent.     Server Timing */
    888 #define MHD_HTTP_HEADER_SERVER_TIMING "Server-Timing"
    889 /* Permanent.     RFC 6265: HTTP State Management Mechanism */
    890 #define MHD_HTTP_HEADER_SET_COOKIE   "Set-Cookie"
    891 /* Permanent.     RFC-ietf-httpbis-message-signatures-19, Section 4.2: HTTP Message Signatures */
    892 #define MHD_HTTP_HEADER_SIGNATURE    "Signature"
    893 /* Permanent.     RFC-ietf-httpbis-message-signatures-19, Section 4.1: HTTP Message Signatures */
    894 #define MHD_HTTP_HEADER_SIGNATURE_INPUT "Signature-Input"
    895 /* Permanent.     RFC 5023: The Atom Publishing Protocol */
    896 #define MHD_HTTP_HEADER_SLUG         "SLUG"
    897 /* Permanent.     Simple Object Access Protocol (SOAP) 1.1 */
    898 #define MHD_HTTP_HEADER_SOAPACTION   "SoapAction"
    899 /* Permanent.     RFC 2518: HTTP Extensions for Distributed Authoring -- WEBDAV */
    900 #define MHD_HTTP_HEADER_STATUS_URI   "Status-URI"
    901 /* Permanent.     RFC 6797: HTTP Strict Transport Security (HSTS) */
    902 #define MHD_HTTP_HEADER_STRICT_TRANSPORT_SECURITY "Strict-Transport-Security"
    903 /* Permanent.     RFC 8594: The Sunset HTTP Header Field */
    904 #define MHD_HTTP_HEADER_SUNSET       "Sunset"
    905 /* Permanent.     Edge Architecture Specification */
    906 #define MHD_HTTP_HEADER_SURROGATE_CAPABILITY "Surrogate-Capability"
    907 /* Permanent.     Edge Architecture Specification */
    908 #define MHD_HTTP_HEADER_SURROGATE_CONTROL "Surrogate-Control"
    909 /* Permanent.     RFC 2295: Transparent Content Negotiation in HTTP */
    910 #define MHD_HTTP_HEADER_TCN          "TCN"
    911 /* Permanent.     RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV) */
    912 #define MHD_HTTP_HEADER_TIMEOUT      "Timeout"
    913 /* Permanent.     RFC 8030, Section 5.4: Generic Event Delivery Using HTTP Push */
    914 #define MHD_HTTP_HEADER_TOPIC        "Topic"
    915 /* Permanent.     Trace Context */
    916 #define MHD_HTTP_HEADER_TRACEPARENT  "Traceparent"
    917 /* Permanent.     Trace Context */
    918 #define MHD_HTTP_HEADER_TRACESTATE   "Tracestate"
    919 /* Permanent.     RFC 8030, Section 5.2: Generic Event Delivery Using HTTP Push */
    920 #define MHD_HTTP_HEADER_TTL          "TTL"
    921 /* Permanent.     RFC 8030, Section 5.3: Generic Event Delivery Using HTTP Push */
    922 #define MHD_HTTP_HEADER_URGENCY      "Urgency"
    923 /* Permanent.     RFC 2295: Transparent Content Negotiation in HTTP */
    924 #define MHD_HTTP_HEADER_VARIANT_VARY "Variant-Vary"
    925 /* Permanent.     RFC-ietf-httpbis-digest-headers-13, Section 4: Digest Fields */
    926 #define MHD_HTTP_HEADER_WANT_CONTENT_DIGEST "Want-Content-Digest"
    927 /* Permanent.     RFC-ietf-httpbis-digest-headers-13, Section 4: Digest Fields */
    928 #define MHD_HTTP_HEADER_WANT_REPR_DIGEST "Want-Repr-Digest"
    929 /* Permanent.     Fetch */
    930 #define MHD_HTTP_HEADER_X_CONTENT_TYPE_OPTIONS "X-Content-Type-Options"
    931 /* Permanent.     HTML */
    932 #define MHD_HTTP_HEADER_X_FRAME_OPTIONS "X-Frame-Options"
    933 /* Provisional.   AMP-Cache-Transform HTTP request header */
    934 #define MHD_HTTP_HEADER_AMP_CACHE_TRANSFORM "AMP-Cache-Transform"
    935 /* Provisional.   OSLC Configuration Management Version 1.0. Part 3: Configuration Specification */
    936 #define MHD_HTTP_HEADER_CONFIGURATION_CONTEXT "Configuration-Context"
    937 /* Provisional.   RFC 6017: Electronic Data Interchange - Internet Integration (EDIINT) Features Header Field */
    938 #define MHD_HTTP_HEADER_EDIINT_FEATURES "EDIINT-Features"
    939 /* Provisional.   OData Version 4.01 Part 1: Protocol; OASIS; Chet_Ensign */
    940 #define MHD_HTTP_HEADER_ISOLATION    "Isolation"
    941 /* Provisional.   Permissions Policy */
    942 #define MHD_HTTP_HEADER_PERMISSIONS_POLICY "Permissions-Policy"
    943 /* Provisional.   Repeatable Requests Version 1.0; OASIS; Chet_Ensign */
    944 #define MHD_HTTP_HEADER_REPEATABILITY_CLIENT_ID "Repeatability-Client-ID"
    945 /* Provisional.   Repeatable Requests Version 1.0; OASIS; Chet_Ensign */
    946 #define MHD_HTTP_HEADER_REPEATABILITY_FIRST_SENT "Repeatability-First-Sent"
    947 /* Provisional.   Repeatable Requests Version 1.0; OASIS; Chet_Ensign */
    948 #define MHD_HTTP_HEADER_REPEATABILITY_REQUEST_ID "Repeatability-Request-ID"
    949 /* Provisional.   Repeatable Requests Version 1.0; OASIS; Chet_Ensign */
    950 #define MHD_HTTP_HEADER_REPEATABILITY_RESULT "Repeatability-Result"
    951 /* Provisional.   Reporting API */
    952 #define MHD_HTTP_HEADER_REPORTING_ENDPOINTS "Reporting-Endpoints"
    953 /* Provisional.   Global Privacy Control (GPC) */
    954 #define MHD_HTTP_HEADER_SEC_GPC      "Sec-GPC"
    955 /* Provisional.   Resource Timing Level 1 */
    956 #define MHD_HTTP_HEADER_TIMING_ALLOW_ORIGIN "Timing-Allow-Origin"
    957 /* Deprecated.    PEP - an Extension Mechanism for HTTP; status-change-http-experiments-to-historic */
    958 #define MHD_HTTP_HEADER_C_PEP_INFO   "C-PEP-Info"
    959 /* Deprecated.    White Paper: Joint Electronic Payment Initiative */
    960 #define MHD_HTTP_HEADER_PROTOCOL_INFO "Protocol-Info"
    961 /* Deprecated.    White Paper: Joint Electronic Payment Initiative */
    962 #define MHD_HTTP_HEADER_PROTOCOL_QUERY "Protocol-Query"
    963 /* Obsoleted.     Access Control for Cross-site Requests */
    964 #define MHD_HTTP_HEADER_ACCESS_CONTROL "Access-Control"
    965 /* Obsoleted.     RFC 2774: An HTTP Extension Framework; status-change-http-experiments-to-historic */
    966 #define MHD_HTTP_HEADER_C_EXT        "C-Ext"
    967 /* Obsoleted.     RFC 2774: An HTTP Extension Framework; status-change-http-experiments-to-historic */
    968 #define MHD_HTTP_HEADER_C_MAN        "C-Man"
    969 /* Obsoleted.     RFC 2774: An HTTP Extension Framework; status-change-http-experiments-to-historic */
    970 #define MHD_HTTP_HEADER_C_OPT        "C-Opt"
    971 /* Obsoleted.     PEP - an Extension Mechanism for HTTP; status-change-http-experiments-to-historic */
    972 #define MHD_HTTP_HEADER_C_PEP        "C-PEP"
    973 /* Obsoleted.     RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1; RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1 */
    974 #define MHD_HTTP_HEADER_CONTENT_BASE "Content-Base"
    975 /* Obsoleted.     RFC 2616, Section 14.15: Hypertext Transfer Protocol -- HTTP/1.1; RFC 7231, Appendix B: Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content */
    976 #define MHD_HTTP_HEADER_CONTENT_MD5  "Content-MD5"
    977 /* Obsoleted.     HTML 4.01 Specification */
    978 #define MHD_HTTP_HEADER_CONTENT_SCRIPT_TYPE "Content-Script-Type"
    979 /* Obsoleted.     HTML 4.01 Specification */
    980 #define MHD_HTTP_HEADER_CONTENT_STYLE_TYPE "Content-Style-Type"
    981 /* Obsoleted.     RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1 */
    982 #define MHD_HTTP_HEADER_CONTENT_VERSION "Content-Version"
    983 /* Obsoleted.     RFC 2965: HTTP State Management Mechanism; RFC 6265: HTTP State Management Mechanism */
    984 #define MHD_HTTP_HEADER_COOKIE2      "Cookie2"
    985 /* Obsoleted.     HTML 4.01 Specification */
    986 #define MHD_HTTP_HEADER_DEFAULT_STYLE "Default-Style"
    987 /* Obsoleted.     RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1 */
    988 #define MHD_HTTP_HEADER_DERIVED_FROM "Derived-From"
    989 /* Obsoleted.     RFC 3230: Instance Digests in HTTP; RFC-ietf-httpbis-digest-headers-13, Section 1.3: Digest Fields */
    990 #define MHD_HTTP_HEADER_DIGEST       "Digest"
    991 /* Obsoleted.     RFC 2774: An HTTP Extension Framework; status-change-http-experiments-to-historic */
    992 #define MHD_HTTP_HEADER_EXT          "Ext"
    993 /* Obsoleted.     Implementation of OPS Over HTTP */
    994 #define MHD_HTTP_HEADER_GETPROFILE   "GetProfile"
    995 /* Obsoleted.     RFC 7540, Section 3.2.1: Hypertext Transfer Protocol Version 2 (HTTP/2) */
    996 #define MHD_HTTP_HEADER_HTTP2_SETTINGS "HTTP2-Settings"
    997 /* Obsoleted.     RFC 2774: An HTTP Extension Framework; status-change-http-experiments-to-historic */
    998 #define MHD_HTTP_HEADER_MAN          "Man"
    999 /* Obsoleted.     Access Control for Cross-site Requests */
   1000 #define MHD_HTTP_HEADER_METHOD_CHECK "Method-Check"
   1001 /* Obsoleted.     Access Control for Cross-site Requests */
   1002 #define MHD_HTTP_HEADER_METHOD_CHECK_EXPIRES "Method-Check-Expires"
   1003 /* Obsoleted.     RFC 2774: An HTTP Extension Framework; status-change-http-experiments-to-historic */
   1004 #define MHD_HTTP_HEADER_OPT          "Opt"
   1005 /* Obsoleted.     The Platform for Privacy Preferences 1.0 (P3P1.0) Specification */
   1006 #define MHD_HTTP_HEADER_P3P          "P3P"
   1007 /* Obsoleted.     PEP - an Extension Mechanism for HTTP */
   1008 #define MHD_HTTP_HEADER_PEP          "PEP"
   1009 /* Obsoleted.     PEP - an Extension Mechanism for HTTP */
   1010 #define MHD_HTTP_HEADER_PEP_INFO     "Pep-Info"
   1011 /* Obsoleted.     PICS Label Distribution Label Syntax and Communication Protocols */
   1012 #define MHD_HTTP_HEADER_PICS_LABEL   "PICS-Label"
   1013 /* Obsoleted.     Implementation of OPS Over HTTP */
   1014 #define MHD_HTTP_HEADER_PROFILEOBJECT "ProfileObject"
   1015 /* Obsoleted.     PICS Label Distribution Label Syntax and Communication Protocols */
   1016 #define MHD_HTTP_HEADER_PROTOCOL     "Protocol"
   1017 /* Obsoleted.     PICS Label Distribution Label Syntax and Communication Protocols */
   1018 #define MHD_HTTP_HEADER_PROTOCOL_REQUEST "Protocol-Request"
   1019 /* Obsoleted.     Notification for Proxy Caches */
   1020 #define MHD_HTTP_HEADER_PROXY_FEATURES "Proxy-Features"
   1021 /* Obsoleted.     Notification for Proxy Caches */
   1022 #define MHD_HTTP_HEADER_PROXY_INSTRUCTION "Proxy-Instruction"
   1023 /* Obsoleted.     RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1 */
   1024 #define MHD_HTTP_HEADER_PUBLIC       "Public"
   1025 /* Obsoleted.     Access Control for Cross-site Requests */
   1026 #define MHD_HTTP_HEADER_REFERER_ROOT "Referer-Root"
   1027 /* Obsoleted.     RFC 2310: The Safe Response Header Field; status-change-http-experiments-to-historic */
   1028 #define MHD_HTTP_HEADER_SAFE         "Safe"
   1029 /* Obsoleted.     RFC 2660: The Secure HyperText Transfer Protocol; status-change-http-experiments-to-historic */
   1030 #define MHD_HTTP_HEADER_SECURITY_SCHEME "Security-Scheme"
   1031 /* Obsoleted.     RFC 2965: HTTP State Management Mechanism; RFC 6265: HTTP State Management Mechanism */
   1032 #define MHD_HTTP_HEADER_SET_COOKIE2  "Set-Cookie2"
   1033 /* Obsoleted.     Implementation of OPS Over HTTP */
   1034 #define MHD_HTTP_HEADER_SETPROFILE   "SetProfile"
   1035 /* Obsoleted.     RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1 */
   1036 #define MHD_HTTP_HEADER_URI          "URI"
   1037 /* Obsoleted.     RFC 3230: Instance Digests in HTTP; RFC-ietf-httpbis-digest-headers-13, Section 1.3: Digest Fields */
   1038 #define MHD_HTTP_HEADER_WANT_DIGEST  "Want-Digest"
   1039 /* Obsoleted.     RFC9111, Section 5.5: HTTP Caching */
   1040 #define MHD_HTTP_HEADER_WARNING      "Warning"
   1041 
   1042 /* Headers removed from the registry. Do not use! */
   1043 /* Obsoleted.     RFC4229 */
   1044 #define MHD_HTTP_HEADER_COMPLIANCE   "Compliance"
   1045 /* Obsoleted.     RFC4229 */
   1046 #define MHD_HTTP_HEADER_CONTENT_TRANSFER_ENCODING "Content-Transfer-Encoding"
   1047 /* Obsoleted.     RFC4229 */
   1048 #define MHD_HTTP_HEADER_COST         "Cost"
   1049 /* Obsoleted.     RFC4229 */
   1050 #define MHD_HTTP_HEADER_MESSAGE_ID   "Message-ID"
   1051 /* Obsoleted.     RFC4229 */
   1052 #define MHD_HTTP_HEADER_NON_COMPLIANCE "Non-Compliance"
   1053 /* Obsoleted.     RFC4229 */
   1054 #define MHD_HTTP_HEADER_OPTIONAL     "Optional"
   1055 /* Obsoleted.     RFC4229 */
   1056 #define MHD_HTTP_HEADER_RESOLUTION_HINT "Resolution-Hint"
   1057 /* Obsoleted.     RFC4229 */
   1058 #define MHD_HTTP_HEADER_RESOLVER_LOCATION "Resolver-Location"
   1059 /* Obsoleted.     RFC4229 */
   1060 #define MHD_HTTP_HEADER_SUBOK        "SubOK"
   1061 /* Obsoleted.     RFC4229 */
   1062 #define MHD_HTTP_HEADER_SUBST        "Subst"
   1063 /* Obsoleted.     RFC4229 */
   1064 #define MHD_HTTP_HEADER_TITLE        "Title"
   1065 /* Obsoleted.     RFC4229 */
   1066 #define MHD_HTTP_HEADER_UA_COLOR     "UA-Color"
   1067 /* Obsoleted.     RFC4229 */
   1068 #define MHD_HTTP_HEADER_UA_MEDIA     "UA-Media"
   1069 /* Obsoleted.     RFC4229 */
   1070 #define MHD_HTTP_HEADER_UA_PIXELS    "UA-Pixels"
   1071 /* Obsoleted.     RFC4229 */
   1072 #define MHD_HTTP_HEADER_UA_RESOLUTION "UA-Resolution"
   1073 /* Obsoleted.     RFC4229 */
   1074 #define MHD_HTTP_HEADER_UA_WINDOWPIXELS "UA-Windowpixels"
   1075 /* Obsoleted.     RFC4229 */
   1076 #define MHD_HTTP_HEADER_VERSION      "Version"
   1077 /* Obsoleted.     W3C Mobile Web Best Practices Working Group */
   1078 #define MHD_HTTP_HEADER_X_DEVICE_ACCEPT "X-Device-Accept"
   1079 /* Obsoleted.     W3C Mobile Web Best Practices Working Group */
   1080 #define MHD_HTTP_HEADER_X_DEVICE_ACCEPT_CHARSET "X-Device-Accept-Charset"
   1081 /* Obsoleted.     W3C Mobile Web Best Practices Working Group */
   1082 #define MHD_HTTP_HEADER_X_DEVICE_ACCEPT_ENCODING "X-Device-Accept-Encoding"
   1083 /* Obsoleted.     W3C Mobile Web Best Practices Working Group */
   1084 #define MHD_HTTP_HEADER_X_DEVICE_ACCEPT_LANGUAGE "X-Device-Accept-Language"
   1085 /* Obsoleted.     W3C Mobile Web Best Practices Working Group */
   1086 #define MHD_HTTP_HEADER_X_DEVICE_USER_AGENT "X-Device-User-Agent"
   1087 
   1088 /** @} */ /* end of group headers */
   1089 
   1090 /**
   1091  * @defgroup versions HTTP versions
   1092  * These strings should be used to match against the first line of the
   1093  * HTTP header.
   1094  * @{
   1095  */
   1096 #define MHD_HTTP_VERSION_1_0 "HTTP/1.0"
   1097 #define MHD_HTTP_VERSION_1_1 "HTTP/1.1"
   1098 
   1099 /** @} */ /* end of group versions */
   1100 
   1101 /**
   1102  * @defgroup methods HTTP methods
   1103  * HTTP methods (as strings).
   1104  * See: https://www.iana.org/assignments/http-methods/http-methods.xml
   1105  * Registry export date: 2023-10-02
   1106  * @{
   1107  */
   1108 
   1109 /* Main HTTP methods. */
   1110 /* Safe.     Idempotent.     RFC9110, Section 9.3.1. */
   1111 #define MHD_HTTP_METHOD_GET      "GET"
   1112 /* Safe.     Idempotent.     RFC9110, Section 9.3.2. */
   1113 #define MHD_HTTP_METHOD_HEAD     "HEAD"
   1114 /* Not safe. Not idempotent. RFC9110, Section 9.3.3. */
   1115 #define MHD_HTTP_METHOD_POST     "POST"
   1116 /* Not safe. Idempotent.     RFC9110, Section 9.3.4. */
   1117 #define MHD_HTTP_METHOD_PUT      "PUT"
   1118 /* Not safe. Idempotent.     RFC9110, Section 9.3.5. */
   1119 #define MHD_HTTP_METHOD_DELETE   "DELETE"
   1120 /* Not safe. Not idempotent. RFC9110, Section 9.3.6. */
   1121 #define MHD_HTTP_METHOD_CONNECT  "CONNECT"
   1122 /* Safe.     Idempotent.     RFC9110, Section 9.3.7. */
   1123 #define MHD_HTTP_METHOD_OPTIONS  "OPTIONS"
   1124 /* Safe.     Idempotent.     RFC9110, Section 9.3.8. */
   1125 #define MHD_HTTP_METHOD_TRACE    "TRACE"
   1126 
   1127 /* Additional HTTP methods. */
   1128 /* Not safe. Idempotent.     RFC3744, Section 8.1. */
   1129 #define MHD_HTTP_METHOD_ACL            "ACL"
   1130 /* Not safe. Idempotent.     RFC3253, Section 12.6. */
   1131 #define MHD_HTTP_METHOD_BASELINE_CONTROL "BASELINE-CONTROL"
   1132 /* Not safe. Idempotent.     RFC5842, Section 4. */
   1133 #define MHD_HTTP_METHOD_BIND           "BIND"
   1134 /* Not safe. Idempotent.     RFC3253, Section 4.4, Section 9.4. */
   1135 #define MHD_HTTP_METHOD_CHECKIN        "CHECKIN"
   1136 /* Not safe. Idempotent.     RFC3253, Section 4.3, Section 8.8. */
   1137 #define MHD_HTTP_METHOD_CHECKOUT       "CHECKOUT"
   1138 /* Not safe. Idempotent.     RFC4918, Section 9.8. */
   1139 #define MHD_HTTP_METHOD_COPY           "COPY"
   1140 /* Not safe. Idempotent.     RFC3253, Section 8.2. */
   1141 #define MHD_HTTP_METHOD_LABEL          "LABEL"
   1142 /* Not safe. Idempotent.     RFC2068, Section 19.6.1.2. */
   1143 #define MHD_HTTP_METHOD_LINK           "LINK"
   1144 /* Not safe. Not idempotent. RFC4918, Section 9.10. */
   1145 #define MHD_HTTP_METHOD_LOCK           "LOCK"
   1146 /* Not safe. Idempotent.     RFC3253, Section 11.2. */
   1147 #define MHD_HTTP_METHOD_MERGE          "MERGE"
   1148 /* Not safe. Idempotent.     RFC3253, Section 13.5. */
   1149 #define MHD_HTTP_METHOD_MKACTIVITY     "MKACTIVITY"
   1150 /* Not safe. Idempotent.     RFC4791, Section 5.3.1; RFC8144, Section 2.3. */
   1151 #define MHD_HTTP_METHOD_MKCALENDAR     "MKCALENDAR"
   1152 /* Not safe. Idempotent.     RFC4918, Section 9.3; RFC5689, Section 3; RFC8144, Section 2.3. */
   1153 #define MHD_HTTP_METHOD_MKCOL          "MKCOL"
   1154 /* Not safe. Idempotent.     RFC4437, Section 6. */
   1155 #define MHD_HTTP_METHOD_MKREDIRECTREF  "MKREDIRECTREF"
   1156 /* Not safe. Idempotent.     RFC3253, Section 6.3. */
   1157 #define MHD_HTTP_METHOD_MKWORKSPACE    "MKWORKSPACE"
   1158 /* Not safe. Idempotent.     RFC4918, Section 9.9. */
   1159 #define MHD_HTTP_METHOD_MOVE           "MOVE"
   1160 /* Not safe. Idempotent.     RFC3648, Section 7. */
   1161 #define MHD_HTTP_METHOD_ORDERPATCH     "ORDERPATCH"
   1162 /* Not safe. Not idempotent. RFC5789, Section 2. */
   1163 #define MHD_HTTP_METHOD_PATCH          "PATCH"
   1164 /* Safe.     Idempotent.     RFC9113, Section 3.4. */
   1165 #define MHD_HTTP_METHOD_PRI            "PRI"
   1166 /* Safe.     Idempotent.     RFC4918, Section 9.1; RFC8144, Section 2.1. */
   1167 #define MHD_HTTP_METHOD_PROPFIND       "PROPFIND"
   1168 /* Not safe. Idempotent.     RFC4918, Section 9.2; RFC8144, Section 2.2. */
   1169 #define MHD_HTTP_METHOD_PROPPATCH      "PROPPATCH"
   1170 /* Not safe. Idempotent.     RFC5842, Section 6. */
   1171 #define MHD_HTTP_METHOD_REBIND         "REBIND"
   1172 /* Safe.     Idempotent.     RFC3253, Section 3.6; RFC8144, Section 2.1. */
   1173 #define MHD_HTTP_METHOD_REPORT         "REPORT"
   1174 /* Safe.     Idempotent.     RFC5323, Section 2. */
   1175 #define MHD_HTTP_METHOD_SEARCH         "SEARCH"
   1176 /* Not safe. Idempotent.     RFC5842, Section 5. */
   1177 #define MHD_HTTP_METHOD_UNBIND         "UNBIND"
   1178 /* Not safe. Idempotent.     RFC3253, Section 4.5. */
   1179 #define MHD_HTTP_METHOD_UNCHECKOUT     "UNCHECKOUT"
   1180 /* Not safe. Idempotent.     RFC2068, Section 19.6.1.3. */
   1181 #define MHD_HTTP_METHOD_UNLINK         "UNLINK"
   1182 /* Not safe. Idempotent.     RFC4918, Section 9.11. */
   1183 #define MHD_HTTP_METHOD_UNLOCK         "UNLOCK"
   1184 /* Not safe. Idempotent.     RFC3253, Section 7.1. */
   1185 #define MHD_HTTP_METHOD_UPDATE         "UPDATE"
   1186 /* Not safe. Idempotent.     RFC4437, Section 7. */
   1187 #define MHD_HTTP_METHOD_UPDATEREDIRECTREF "UPDATEREDIRECTREF"
   1188 /* Not safe. Idempotent.     RFC3253, Section 3.5. */
   1189 #define MHD_HTTP_METHOD_VERSION_CONTROL "VERSION-CONTROL"
   1190 /* Not safe. Not idempotent. RFC9110, Section 18.2. */
   1191 #define MHD_HTTP_METHOD_ASTERISK       "*"
   1192 
   1193 /** @} */ /* end of group methods */
   1194 
   1195 /**
   1196  * @defgroup postenc HTTP POST encodings
   1197  * See also: http://www.w3.org/TR/html4/interact/forms.html#h-17.13.4
   1198  * @{
   1199  */
   1200 #define MHD_HTTP_POST_ENCODING_FORM_URLENCODED \
   1201         "application/x-www-form-urlencoded"
   1202 #define MHD_HTTP_POST_ENCODING_MULTIPART_FORMDATA "multipart/form-data"
   1203 
   1204 /** @} */ /* end of group postenc */
   1205 
   1206 
   1207 /**
   1208  * @brief Handle for the daemon (listening on a socket for HTTP traffic).
   1209  * @ingroup event
   1210  */
   1211 struct MHD_Daemon;
   1212 
   1213 /**
   1214  * @brief Handle for a connection / HTTP request.
   1215  *
   1216  * With HTTP/1.1, multiple requests can be run over the same
   1217  * connection.  However, MHD will only show one request per TCP
   1218  * connection to the client at any given time.
   1219  * @ingroup request
   1220  */
   1221 struct MHD_Connection;
   1222 
   1223 /**
   1224  * @brief Handle for a response.
   1225  * @ingroup response
   1226  */
   1227 struct MHD_Response;
   1228 
   1229 /**
   1230  * @brief Handle for POST processing.
   1231  * @ingroup response
   1232  */
   1233 struct MHD_PostProcessor;
   1234 
   1235 
   1236 /**
   1237  * @brief Flags for the `struct MHD_Daemon`.
   1238  *
   1239  * Note that MHD will run automatically in background thread(s) only
   1240  * if #MHD_USE_INTERNAL_POLLING_THREAD is used. Otherwise caller (application)
   1241  * must use #MHD_run() or #MHD_run_from_select() to have MHD processed
   1242  * network connections and data.
   1243  *
   1244  * Starting the daemon may also fail if a particular option is not
   1245  * implemented or not supported on the target platform (i.e. no
   1246  * support for TLS, epoll or IPv6).
   1247  */
   1248 enum MHD_FLAG
   1249 {
   1250   /**
   1251    * No options selected.
   1252    */
   1253   MHD_NO_FLAG = 0,
   1254 
   1255   /**
   1256    * Print errors messages to custom error logger or to `stderr` if
   1257    * custom error logger is not set.
   1258    * @sa ::MHD_OPTION_EXTERNAL_LOGGER
   1259    */
   1260   MHD_USE_ERROR_LOG = 1,
   1261 
   1262   /**
   1263    * Run in debug mode.  If this flag is used, the library should
   1264    * print error messages and warnings to `stderr`.
   1265    */
   1266   MHD_USE_DEBUG = 1,
   1267 
   1268   /**
   1269    * Run in HTTPS mode.  The modern protocol is called TLS.
   1270    */
   1271   MHD_USE_TLS = 2,
   1272 
   1273   /** @deprecated */
   1274   MHD_USE_SSL = 2,
   1275 #if 0
   1276   /* let's do this later once versions that define MHD_USE_TLS a more widely deployed. */
   1277 #define MHD_USE_SSL \
   1278         _MHD_DEPR_IN_MACRO ("Value MHD_USE_SSL is deprecated, use MHD_USE_TLS") \
   1279         MHD_USE_TLS
   1280 #endif
   1281 
   1282   /**
   1283    * Run using one thread per connection.
   1284    * Must be used only with #MHD_USE_INTERNAL_POLLING_THREAD.
   1285    *
   1286    * If #MHD_USE_ITC is also not used, closed and expired connections may only
   1287    * be cleaned up internally when a new connection is received.
   1288    * Consider adding of #MHD_USE_ITC flag to have faster internal cleanups
   1289    * at very minor increase in system resources usage.
   1290    */
   1291   MHD_USE_THREAD_PER_CONNECTION = 4,
   1292 
   1293   /**
   1294    * Run using an internal thread (or thread pool) for sockets sending
   1295    * and receiving and data processing. Without this flag MHD will not
   1296    * run automatically in background thread(s).
   1297    * If this flag is set, #MHD_run() and #MHD_run_from_select() couldn't
   1298    * be used.
   1299    * This flag is set explicitly by #MHD_USE_POLL_INTERNAL_THREAD and
   1300    * by #MHD_USE_EPOLL_INTERNAL_THREAD.
   1301    * When this flag is not set, MHD run in "external" polling mode.
   1302    */
   1303   MHD_USE_INTERNAL_POLLING_THREAD = 8,
   1304 
   1305   /** @deprecated */
   1306   MHD_USE_SELECT_INTERNALLY = 8,
   1307 #if 0 /* Will be marked for real deprecation later. */
   1308 #define MHD_USE_SELECT_INTERNALLY \
   1309         _MHD_DEPR_IN_MACRO ( \
   1310           "Value MHD_USE_SELECT_INTERNALLY is deprecated, use MHD_USE_INTERNAL_POLLING_THREAD instead") \
   1311         MHD_USE_INTERNAL_POLLING_THREAD
   1312 #endif /* 0 */
   1313 
   1314   /**
   1315    * Run using the IPv6 protocol (otherwise, MHD will just support
   1316    * IPv4).  If you want MHD to support IPv4 and IPv6 using a single
   1317    * socket, pass #MHD_USE_DUAL_STACK, otherwise, if you only pass
   1318    * this option, MHD will try to bind to IPv6-only (resulting in
   1319    * no IPv4 support).
   1320    */
   1321   MHD_USE_IPv6 = 16,
   1322 
   1323   /**
   1324    * Be pedantic about the protocol (as opposed to as tolerant as
   1325    * possible).
   1326    * This flag is equivalent to setting 1 as #MHD_OPTION_CLIENT_DISCIPLINE_LVL
   1327    * value.
   1328    * @sa #MHD_OPTION_CLIENT_DISCIPLINE_LVL
   1329    */
   1330   MHD_USE_PEDANTIC_CHECKS = 32,
   1331 #if 0 /* Will be marked for real deprecation later. */
   1332 #define MHD_USE_PEDANTIC_CHECKS \
   1333         _MHD_DEPR_IN_MACRO ( \
   1334           "Flag MHD_USE_PEDANTIC_CHECKS is deprecated, " \
   1335           "use option MHD_OPTION_CLIENT_DISCIPLINE_LVL instead") \
   1336         32
   1337 #endif /* 0 */
   1338 
   1339   /**
   1340    * Use `poll()` instead of `select()` for polling sockets.
   1341    * This allows sockets with `fd >= FD_SETSIZE`.
   1342    * This option is not compatible with an "external" polling mode
   1343    * (as there is no API to get the file descriptors for the external
   1344    * poll() from MHD) and must also not be used in combination
   1345    * with #MHD_USE_EPOLL.
   1346    * @sa ::MHD_FEATURE_POLL, #MHD_USE_POLL_INTERNAL_THREAD
   1347    */
   1348   MHD_USE_POLL = 64,
   1349 
   1350   /**
   1351    * Run using an internal thread (or thread pool) doing `poll()`.
   1352    * @sa ::MHD_FEATURE_POLL, #MHD_USE_POLL, #MHD_USE_INTERNAL_POLLING_THREAD
   1353    */
   1354   MHD_USE_POLL_INTERNAL_THREAD = MHD_USE_POLL | MHD_USE_INTERNAL_POLLING_THREAD,
   1355 
   1356   /** @deprecated */
   1357   MHD_USE_POLL_INTERNALLY = MHD_USE_POLL | MHD_USE_INTERNAL_POLLING_THREAD,
   1358 #if 0 /* Will be marked for real deprecation later. */
   1359 #define MHD_USE_POLL_INTERNALLY \
   1360         _MHD_DEPR_IN_MACRO ( \
   1361           "Value MHD_USE_POLL_INTERNALLY is deprecated, use MHD_USE_POLL_INTERNAL_THREAD instead") \
   1362         MHD_USE_POLL_INTERNAL_THREAD
   1363 #endif /* 0 */
   1364 
   1365   /**
   1366    * Suppress (automatically) adding the 'Date:' header to HTTP responses.
   1367    * This option should ONLY be used on systems that do not have a clock
   1368    * and that DO provide other mechanisms for cache control.  See also
   1369    * RFC 2616, section 14.18 (exception 3).
   1370    */
   1371   MHD_USE_SUPPRESS_DATE_NO_CLOCK = 128,
   1372 
   1373   /** @deprecated */
   1374   MHD_SUPPRESS_DATE_NO_CLOCK = 128,
   1375 #if 0 /* Will be marked for real deprecation later. */
   1376 #define MHD_SUPPRESS_DATE_NO_CLOCK \
   1377         _MHD_DEPR_IN_MACRO ( \
   1378           "Value MHD_SUPPRESS_DATE_NO_CLOCK is deprecated, use MHD_USE_SUPPRESS_DATE_NO_CLOCK instead") \
   1379         MHD_USE_SUPPRESS_DATE_NO_CLOCK
   1380 #endif /* 0 */
   1381 
   1382   /**
   1383    * Run without a listen socket.  This option only makes sense if
   1384    * #MHD_add_connection is to be used exclusively to connect HTTP
   1385    * clients to the HTTP server.  This option is incompatible with
   1386    * using a thread pool; if it is used, #MHD_OPTION_THREAD_POOL_SIZE
   1387    * is ignored.
   1388    */
   1389   MHD_USE_NO_LISTEN_SOCKET = 256,
   1390 
   1391   /**
   1392    * Use `epoll()` instead of `select()` or `poll()` for the event loop.
   1393    * This option is only available on some systems; using the option on
   1394    * systems without epoll will cause #MHD_start_daemon to fail.  Using
   1395    * this option is not supported with #MHD_USE_THREAD_PER_CONNECTION.
   1396    * @sa ::MHD_FEATURE_EPOLL
   1397    */
   1398   MHD_USE_EPOLL = 512,
   1399 
   1400   /** @deprecated */
   1401   MHD_USE_EPOLL_LINUX_ONLY = 512,
   1402 #if 0 /* Will be marked for real deprecation later. */
   1403 #define MHD_USE_EPOLL_LINUX_ONLY \
   1404         _MHD_DEPR_IN_MACRO ( \
   1405           "Value MHD_USE_EPOLL_LINUX_ONLY is deprecated, use MHD_USE_EPOLL") \
   1406         MHD_USE_EPOLL
   1407 #endif /* 0 */
   1408 
   1409   /**
   1410    * Run using an internal thread (or thread pool) doing `epoll` polling.
   1411    * This option is only available on certain platforms; using the option on
   1412    * platform without `epoll` support will cause #MHD_start_daemon to fail.
   1413    * @sa ::MHD_FEATURE_EPOLL, #MHD_USE_EPOLL, #MHD_USE_INTERNAL_POLLING_THREAD
   1414    */
   1415   MHD_USE_EPOLL_INTERNAL_THREAD = MHD_USE_EPOLL
   1416                                   | MHD_USE_INTERNAL_POLLING_THREAD,
   1417 
   1418   /** @deprecated */
   1419   MHD_USE_EPOLL_INTERNALLY = MHD_USE_EPOLL | MHD_USE_INTERNAL_POLLING_THREAD,
   1420   /** @deprecated */
   1421   MHD_USE_EPOLL_INTERNALLY_LINUX_ONLY = MHD_USE_EPOLL
   1422                                         | MHD_USE_INTERNAL_POLLING_THREAD,
   1423 #if 0 /* Will be marked for real deprecation later. */
   1424 #define MHD_USE_EPOLL_INTERNALLY \
   1425         _MHD_DEPR_IN_MACRO ( \
   1426           "Value MHD_USE_EPOLL_INTERNALLY is deprecated, use MHD_USE_EPOLL_INTERNAL_THREAD") \
   1427         MHD_USE_EPOLL_INTERNAL_THREAD
   1428   /** @deprecated */
   1429 #define MHD_USE_EPOLL_INTERNALLY_LINUX_ONLY \
   1430         _MHD_DEPR_IN_MACRO ( \
   1431           "Value MHD_USE_EPOLL_INTERNALLY_LINUX_ONLY is deprecated, use MHD_USE_EPOLL_INTERNAL_THREAD") \
   1432         MHD_USE_EPOLL_INTERNAL_THREAD
   1433 #endif /* 0 */
   1434 
   1435   /**
   1436    * Use inter-thread communication channel.
   1437    * #MHD_USE_ITC can be used with #MHD_USE_INTERNAL_POLLING_THREAD
   1438    * and is ignored with any "external" sockets polling.
   1439    * It's required for use of #MHD_quiesce_daemon
   1440    * or #MHD_add_connection.
   1441    * This option is enforced by #MHD_ALLOW_SUSPEND_RESUME or
   1442    * #MHD_USE_NO_LISTEN_SOCKET.
   1443    * Note that while this flag has no effect of its own with "external"
   1444    * sockets polling, the channel implied by #MHD_ALLOW_SUSPEND_RESUME
   1445    * is created and used in that mode as well: #MHD_get_fdset() adds it
   1446    * to the read set, so that #MHD_resume_connection() called from
   1447    * another thread interrupts a blocking select()/poll() of the
   1448    * application.  See #MHD_resume_connection().
   1449    * #MHD_USE_ITC is always used automatically on platforms
   1450    * where select()/poll()/other ignore shutdown of listen
   1451    * socket.
   1452    */
   1453   MHD_USE_ITC = 1024,
   1454 
   1455   /** @deprecated */
   1456   MHD_USE_PIPE_FOR_SHUTDOWN = 1024,
   1457 #if 0 /* Will be marked for real deprecation later. */
   1458 #define MHD_USE_PIPE_FOR_SHUTDOWN \
   1459         _MHD_DEPR_IN_MACRO ( \
   1460           "Value MHD_USE_PIPE_FOR_SHUTDOWN is deprecated, use MHD_USE_ITC") \
   1461         MHD_USE_ITC
   1462 #endif /* 0 */
   1463 
   1464   /**
   1465    * Use a single socket for IPv4 and IPv6.
   1466    */
   1467   MHD_USE_DUAL_STACK = MHD_USE_IPv6 | 2048,
   1468 
   1469   /**
   1470    * Enable `turbo`.  Disables certain calls to `shutdown()`,
   1471    * enables aggressive non-blocking optimistic reads and
   1472    * other potentially unsafe optimizations.
   1473    * Most effects only happen with #MHD_USE_EPOLL.
   1474    */
   1475   MHD_USE_TURBO = 4096,
   1476 
   1477   /** @deprecated */
   1478   MHD_USE_EPOLL_TURBO = 4096,
   1479 #if 0 /* Will be marked for real deprecation later. */
   1480 #define MHD_USE_EPOLL_TURBO \
   1481         _MHD_DEPR_IN_MACRO ( \
   1482           "Value MHD_USE_EPOLL_TURBO is deprecated, use MHD_USE_TURBO") \
   1483         MHD_USE_TURBO
   1484 #endif /* 0 */
   1485 
   1486   /**
   1487    * Enable suspend/resume functions, which also implies setting up
   1488    * ITC to signal resume.
   1489    */
   1490   MHD_ALLOW_SUSPEND_RESUME = 8192 | MHD_USE_ITC,
   1491 
   1492   /** @deprecated */
   1493   MHD_USE_SUSPEND_RESUME = 8192 | MHD_USE_ITC,
   1494 #if 0 /* Will be marked for real deprecation later. */
   1495 #define MHD_USE_SUSPEND_RESUME \
   1496         _MHD_DEPR_IN_MACRO ( \
   1497           "Value MHD_USE_SUSPEND_RESUME is deprecated, use MHD_ALLOW_SUSPEND_RESUME instead") \
   1498         MHD_ALLOW_SUSPEND_RESUME
   1499 #endif /* 0 */
   1500 
   1501   /**
   1502    * Enable TCP_FASTOPEN option.  This option is only available on Linux with a
   1503    * kernel >= 3.6.  On other systems, using this option cases #MHD_start_daemon
   1504    * to fail.
   1505    */
   1506   MHD_USE_TCP_FASTOPEN = 16384,
   1507 
   1508   /**
   1509    * You need to set this option if you want to use HTTP "Upgrade".
   1510    * "Upgrade" may require usage of additional internal resources,
   1511    * which we do not want to use unless necessary.
   1512    */
   1513   MHD_ALLOW_UPGRADE = 32768,
   1514 
   1515   /**
   1516    * Automatically use best available polling function.
   1517    * Choice of polling function is also depend on other daemon options.
   1518    * If #MHD_USE_INTERNAL_POLLING_THREAD is specified then epoll, poll() or
   1519    * select() will be used (listed in decreasing preference order, first
   1520    * function available on system will be used).
   1521    * If #MHD_USE_THREAD_PER_CONNECTION is specified then poll() or select()
   1522    * will be used.
   1523    * If those flags are not specified then epoll or select() will be
   1524    * used (as the only suitable for MHD_get_fdset())
   1525    */
   1526   MHD_USE_AUTO = 65536,
   1527 
   1528   /**
   1529    * Run using an internal thread (or thread pool) with best available on
   1530    * system polling function.
   1531    * This is combination of #MHD_USE_AUTO and #MHD_USE_INTERNAL_POLLING_THREAD
   1532    * flags.
   1533    */
   1534   MHD_USE_AUTO_INTERNAL_THREAD = MHD_USE_AUTO | MHD_USE_INTERNAL_POLLING_THREAD,
   1535 
   1536   /**
   1537    * Flag set to enable post-handshake client authentication
   1538    * (only useful in combination with #MHD_USE_TLS).
   1539    */
   1540   MHD_USE_POST_HANDSHAKE_AUTH_SUPPORT = 1U << 17,
   1541 
   1542   /**
   1543    * Flag set to enable TLS 1.3 early data.  This has
   1544    * security implications, be VERY careful when using this.
   1545    */
   1546   MHD_USE_INSECURE_TLS_EARLY_DATA = 1U << 18,
   1547 
   1548   /**
   1549    * Indicates that MHD daemon will be used by application in single-threaded
   1550    * mode only.  When this flag is set then application must call any MHD
   1551    * function only within a single thread.
   1552    * This flag turns off some internal thread-safety and allows MHD making
   1553    * some of the internal optimisations suitable only for single-threaded
   1554    * environment.
   1555    * Not compatible with #MHD_USE_INTERNAL_POLLING_THREAD.
   1556    * @note Available since #MHD_VERSION 0x00097707
   1557    */
   1558   MHD_USE_NO_THREAD_SAFETY = 1U << 19
   1559 
   1560 };
   1561 
   1562 
   1563 /**
   1564  * Type of a callback function used for logging by MHD.
   1565  *
   1566  * @param cls closure
   1567  * @param fm format string (`printf()`-style)
   1568  * @param ap arguments to @a fm
   1569  * @ingroup logging
   1570  */
   1571 typedef void
   1572 (*MHD_LogCallback)(void *cls,
   1573                    const char *fm,
   1574                    va_list ap);
   1575 
   1576 
   1577 /**
   1578  * Function called to lookup the pre shared key (@a psk) for a given
   1579  * HTTP connection based on the @a username.
   1580  *
   1581  * @param cls closure
   1582  * @param connection the HTTPS connection
   1583  * @param username the user name claimed by the other side
   1584  * @param[out] psk to be set to the pre-shared-key; should be allocated with malloc(),
   1585  *                 will be freed by MHD
   1586  * @param[out] psk_size to be set to the number of bytes in @a psk;
   1587  *                 must be at least 16 (RFC 4279 section 7.1), otherwise
   1588  *                 MHD discards the key and fails the authentication
   1589  * @return 0 on success, -1 on errors
   1590  */
   1591 typedef int
   1592 (*MHD_PskServerCredentialsCallback)(void *cls,
   1593                                     const struct MHD_Connection *connection,
   1594                                     const char *username,
   1595                                     void **psk,
   1596                                     size_t *psk_size);
   1597 
   1598 /**
   1599  * Values for #MHD_OPTION_DIGEST_AUTH_NONCE_BIND_TYPE.
   1600  *
   1601  * These values can limit the scope of validity of MHD-generated nonces.
   1602  * Values can be combined with bitwise OR.
   1603  * Any value, except #MHD_DAUTH_BIND_NONCE_NONE, enforce function
   1604  * #MHD_digest_auth_check3() (and similar functions) to check nonce by
   1605  * re-generating it again with the same parameters, which is CPU-intensive
   1606  * operation.
   1607  * @note Available since #MHD_VERSION 0x00097701
   1608  */
   1609 enum MHD_DAuthBindNonce
   1610 {
   1611   /**
   1612    * Generated nonces are valid for any request from any client until expired.
   1613    * This is default and recommended value.
   1614    * #MHD_digest_auth_check3() (and similar functions) would check only whether
   1615    * the nonce value that is used by client has been generated by MHD and not
   1616    * expired yet.
   1617    * It is recommended because RFC 7616 allows clients to use the same nonce
   1618    * for any request in the same "protection space".
   1619    * When checking client's authorisation requests CPU is loaded less if this
   1620    * value is used.
   1621    * This mode gives MHD maximum flexibility for nonces generation and can
   1622    * prevent possible nonce collisions (and corresponding log warning messages)
   1623    * when clients' requests are intensive.
   1624    * This value cannot be biwise-OR combined with other values.
   1625    */
   1626   MHD_DAUTH_BIND_NONCE_NONE = 0,
   1627 
   1628   /**
   1629    * Generated nonces are valid only for the same realm.
   1630    */
   1631   MHD_DAUTH_BIND_NONCE_REALM = 1 << 0,
   1632 
   1633   /**
   1634    * Generated nonces are valid only for the same URI (excluding parameters
   1635    * after '?' in URI) and request method (GET, POST etc).
   1636    * Not recommended unless "protection space" is limited to a single URI as
   1637    * RFC 7616 allows clients to re-use server-generated nonces for any URI
   1638    * in the same "protection space" which by default consists of all server
   1639    * URIs.
   1640    * Before #MHD_VERSION 0x00097701 this was default (and only supported)
   1641    * nonce bind type.
   1642    */
   1643   MHD_DAUTH_BIND_NONCE_URI = 1 << 1,
   1644 
   1645   /**
   1646    * Generated nonces are valid only for the same URI including URI parameters
   1647    * and request method (GET, POST etc).
   1648    * This value implies #MHD_DAUTH_BIND_NONCE_URI.
   1649    * Not recommended for that same reasons as #MHD_DAUTH_BIND_NONCE_URI.
   1650    */
   1651   MHD_DAUTH_BIND_NONCE_URI_PARAMS = 1 << 2,
   1652 
   1653   /**
   1654    * Generated nonces are valid only for the single client's IP.
   1655    * While it looks like security improvement, in practice the same client may
   1656    * jump from one IP to another (mobile or Wi-Fi handover, DHCP re-assignment,
   1657    * Multi-NAT, different proxy chain and other reasons), while IP address
   1658    * spoofing could be used relatively easily.
   1659    */
   1660   MHD_DAUTH_BIND_NONCE_CLIENT_IP = 1 << 3
   1661 } _MHD_FLAGS_ENUM;
   1662 
   1663 /**
   1664  * @brief MHD options.
   1665  *
   1666  * Passed in the varargs portion of #MHD_start_daemon.
   1667  */
   1668 enum MHD_OPTION
   1669 {
   1670 
   1671   /**
   1672    * No more options / last option.  This is used
   1673    * to terminate the VARARGs list.
   1674    */
   1675   MHD_OPTION_END = 0,
   1676 
   1677   /**
   1678    * Maximum memory size per connection (followed by a `size_t`).
   1679    * Default is 32 kb (#MHD_POOL_SIZE_DEFAULT).
   1680    * Values above 128k are unlikely to result in much benefit, as half
   1681    * of the memory will be typically used for IO, and TCP buffers are
   1682    * unlikely to support window sizes above 64k on most systems.
   1683    * Values below 64 bytes are completely unusable.
   1684    * Since #MHD_VERSION 0x00097710 silently ignored if followed by zero value.
   1685    */
   1686   MHD_OPTION_CONNECTION_MEMORY_LIMIT = 1,
   1687 
   1688   /**
   1689    * Maximum number of concurrent connections to
   1690    * accept (followed by an `unsigned int`).
   1691    */
   1692   MHD_OPTION_CONNECTION_LIMIT = 2,
   1693 
   1694   /**
   1695    * After how many seconds of inactivity should a
   1696    * connection automatically be timed out? (followed
   1697    * by an `unsigned int`; use zero for no timeout).
   1698    * Values larger than (UINT64_MAX / 2000 - 1) will
   1699    * be clipped to this number.
   1700    */
   1701   MHD_OPTION_CONNECTION_TIMEOUT = 3,
   1702 
   1703   /**
   1704    * Register a function that should be called whenever a request has
   1705    * been completed (this can be used for application-specific clean
   1706    * up).  Requests that have never been presented to the application
   1707    * (via #MHD_AccessHandlerCallback) will not result in
   1708    * notifications.
   1709    *
   1710    * This option should be followed by TWO pointers.  First a pointer
   1711    * to a function of type #MHD_RequestCompletedCallback and second a
   1712    * pointer to a closure to pass to the request completed callback.
   1713    * The second pointer may be NULL.
   1714    */
   1715   MHD_OPTION_NOTIFY_COMPLETED = 4,
   1716 
   1717   /**
   1718    * Limit on the number of (concurrent) connections made to the
   1719    * server from the same IP address.  Can be used to prevent one
   1720    * IP from taking over all of the allowed connections.  If the
   1721    * same IP tries to establish more than the specified number of
   1722    * connections, they will be immediately rejected.  The option
   1723    * should be followed by an `unsigned int`.  The default is
   1724    * zero, which means no limit on the number of connections
   1725    * from the same IP address.
   1726    */
   1727   MHD_OPTION_PER_IP_CONNECTION_LIMIT = 5,
   1728 
   1729   /**
   1730    * Bind daemon to the supplied `struct sockaddr`. This option should
   1731    * be followed by a `struct sockaddr *`.  If #MHD_USE_IPv6 is
   1732    * specified, the `struct sockaddr*` should point to a `struct
   1733    * sockaddr_in6`, otherwise to a `struct sockaddr_in`.
   1734    * Silently ignored if followed by NULL pointer.
   1735    * @deprecated Use #MHD_OPTION_SOCK_ADDR_LEN
   1736    */
   1737   MHD_OPTION_SOCK_ADDR = 6,
   1738 
   1739   /**
   1740    * Specify a function that should be called before parsing the URI from
   1741    * the client.  The specified callback function can be used for processing
   1742    * the URI (including the options) before it is parsed.  The URI after
   1743    * parsing will no longer contain the options, which maybe inconvenient for
   1744    * logging.  This option should be followed by two arguments, the first
   1745    * one must be of the form
   1746    *
   1747    *     void * my_logger(void *cls, const char *uri, struct MHD_Connection *con)
   1748    *
   1749    * where the return value will be passed as
   1750    * (`* req_cls`) in calls to the #MHD_AccessHandlerCallback
   1751    * when this request is processed later; returning a
   1752    * value of NULL has no special significance (however,
   1753    * note that if you return non-NULL, you can no longer
   1754    * rely on the first call to the access handler having
   1755    * `NULL == *req_cls` on entry;)
   1756    * "cls" will be set to the second argument following
   1757    * #MHD_OPTION_URI_LOG_CALLBACK.  Finally, uri will
   1758    * be the 0-terminated URI of the request.
   1759    *
   1760    * Note that during the time of this call, most of the connection's
   1761    * state is not initialized (as we have not yet parsed the headers).
   1762    * However, information about the connecting client (IP, socket)
   1763    * is available.
   1764    *
   1765    * The specified function is called only once per request, therefore some
   1766    * programmers may use it to instantiate their own request objects, freeing
   1767    * them in the notifier #MHD_OPTION_NOTIFY_COMPLETED.
   1768    */
   1769   MHD_OPTION_URI_LOG_CALLBACK = 7,
   1770 
   1771   /**
   1772    * Memory pointer for the private key (key.pem) to be used by the
   1773    * HTTPS daemon.  This option should be followed by a
   1774    * `const char *` argument.
   1775    * This should be used in conjunction with #MHD_OPTION_HTTPS_MEM_CERT.
   1776    */
   1777   MHD_OPTION_HTTPS_MEM_KEY = 8,
   1778 
   1779   /**
   1780    * Memory pointer for the certificate (cert.pem) to be used by the
   1781    * HTTPS daemon.  This option should be followed by a
   1782    * `const char *` argument.
   1783    * This should be used in conjunction with #MHD_OPTION_HTTPS_MEM_KEY.
   1784    */
   1785   MHD_OPTION_HTTPS_MEM_CERT = 9,
   1786 
   1787   /**
   1788    * Daemon credentials type.
   1789    * Followed by an argument of type
   1790    * `gnutls_credentials_type_t`.
   1791    */
   1792   MHD_OPTION_HTTPS_CRED_TYPE = 10,
   1793 
   1794   /**
   1795    * Memory pointer to a `const char *` specifying the GnuTLS priorities string.
   1796    * If this options is not specified, then MHD will try the following strings:
   1797    * * "@LIBMICROHTTPD" (application-specific system-wide configuration)
   1798    * * "@SYSTEM"        (system-wide configuration)
   1799    * * default GnuTLS priorities string
   1800    * * "NORMAL"
   1801    * The first configuration accepted by GnuTLS will be used.
   1802    * For more details see GnuTLS documentation for "Application-specific
   1803    * priority strings".
   1804    */
   1805   MHD_OPTION_HTTPS_PRIORITIES = 11,
   1806 
   1807   /**
   1808    * Pass a listen socket for MHD to use (systemd-style).  If this
   1809    * option is used, MHD will not open its own listen socket(s). The
   1810    * argument passed must be of type `MHD_socket` and refer to an
   1811    * existing socket that has been bound to a port and is listening.
   1812    * If followed by MHD_INVALID_SOCKET value, MHD ignores this option
   1813    * and creates socket by itself.
   1814    */
   1815   MHD_OPTION_LISTEN_SOCKET = 12,
   1816 
   1817   /**
   1818    * Use the given function for logging error messages.  This option
   1819    * must be followed by two arguments; the first must be a pointer to
   1820    * a function of type #MHD_LogCallback and the second a pointer
   1821    * `void *` which will be passed as the first argument to the log
   1822    * callback.
   1823    * Should be specified as the first option, otherwise some messages
   1824    * may be printed by standard MHD logger during daemon startup.
   1825    *
   1826    * Note that MHD will not generate any log messages
   1827    * if it was compiled without the "--enable-messages"
   1828    * flag being set.
   1829    */
   1830   MHD_OPTION_EXTERNAL_LOGGER = 13,
   1831 
   1832   /**
   1833    * Number (`unsigned int`) of threads in thread pool. Enable
   1834    * thread pooling by setting this value to to something
   1835    * greater than 1.
   1836    * Can be used only for daemons started with #MHD_USE_INTERNAL_POLLING_THREAD.
   1837    * Ignored if followed by zero value.
   1838    */
   1839   MHD_OPTION_THREAD_POOL_SIZE = 14,
   1840 
   1841   /**
   1842    * Additional options given in an array of `struct MHD_OptionItem`.
   1843    * The array must be terminated with an entry `{MHD_OPTION_END, 0, NULL}`.
   1844    * An example for code using #MHD_OPTION_ARRAY is:
   1845    *
   1846    *     struct MHD_OptionItem ops[] = {
   1847    *       { MHD_OPTION_CONNECTION_LIMIT, 100, NULL },
   1848    *       { MHD_OPTION_CONNECTION_TIMEOUT, 10, NULL },
   1849    *       { MHD_OPTION_END, 0, NULL }
   1850    *     };
   1851    *     d = MHD_start_daemon (0, 8080, NULL, NULL, dh, NULL,
   1852    *                           MHD_OPTION_ARRAY, ops,
   1853    *                           MHD_OPTION_END);
   1854    *
   1855    * For options that expect a single pointer argument, the
   1856    * 'value' member of the `struct MHD_OptionItem` is ignored.
   1857    * For options that expect two pointer arguments, the first
   1858    * argument must be cast to `intptr_t`.
   1859    */
   1860   MHD_OPTION_ARRAY = 15,
   1861 
   1862   /**
   1863    * Specify a function that should be called for unescaping escape
   1864    * sequences in URIs and URI arguments.  Note that this function
   1865    * will NOT be used by the `struct MHD_PostProcessor`.  If this
   1866    * option is not specified, the default method will be used which
   1867    * decodes escape sequences of the form "%HH".  This option should
   1868    * be followed by two arguments, the first one must be of the form
   1869    *
   1870    *     size_t my_unescaper(void *cls,
   1871    *                         struct MHD_Connection *c,
   1872    *                         char *s)
   1873    *
   1874    * where the return value must be the length of the value left in
   1875    * "s" (without the 0-terminator) and "s" should be updated.  Note
   1876    * that the unescape function must not lengthen "s" (the result must
   1877    * be shorter than the input and must still be 0-terminated).
   1878    * However, it may also include binary zeros before the
   1879    * 0-termination.  "cls" will be set to the second argument
   1880    * following #MHD_OPTION_UNESCAPE_CALLBACK.
   1881    */
   1882   MHD_OPTION_UNESCAPE_CALLBACK = 16,
   1883 
   1884   /**
   1885    * Memory pointer for the random values to be used by the Digest
   1886    * Auth module. This option should be followed by two arguments.
   1887    * First an integer of type `size_t` which specifies the size
   1888    * of the buffer pointed to by the second argument in bytes.
   1889    * The recommended size is between 8 and 32. If size is four or less
   1890    * then security could be lowered. Sizes more then 32 (or, probably
   1891    * more than 16 - debatable) will not increase security.
   1892    * Note that the application must ensure that the buffer of the
   1893    * second argument remains allocated and unmodified while the
   1894    * daemon is running.
   1895    * @sa #MHD_OPTION_DIGEST_AUTH_RANDOM_COPY
   1896    */
   1897   MHD_OPTION_DIGEST_AUTH_RANDOM = 17,
   1898 
   1899   /**
   1900    * Size of the internal array holding the map of the nonce and
   1901    * the nonce counter. This option should be followed by an `unsigned int`
   1902    * argument.
   1903    * The map size is 4 by default, which is enough to communicate with
   1904    * a single client at any given moment of time, but not enough to
   1905    * handle several clients simultaneously.
   1906    * If Digest Auth is not used, this option can be set to zero to minimise
   1907    * memory allocation.
   1908    */
   1909   MHD_OPTION_NONCE_NC_SIZE = 18,
   1910 
   1911   /**
   1912    * Desired size of the stack for threads created by MHD. Followed
   1913    * by an argument of type `size_t`.  Use 0 for system default.
   1914    */
   1915   MHD_OPTION_THREAD_STACK_SIZE = 19,
   1916 
   1917   /**
   1918    * Memory pointer for the certificate (ca.pem) to be used by the
   1919    * HTTPS daemon for client authentication.
   1920    * This option should be followed by a `const char *` argument.
   1921    */
   1922   MHD_OPTION_HTTPS_MEM_TRUST = 20,
   1923 
   1924   /**
   1925    * Increment to use for growing the read buffer (followed by a
   1926    * `size_t`).
   1927    * Must not be higher than 1/4 of #MHD_OPTION_CONNECTION_MEMORY_LIMIT.
   1928    * Since #MHD_VERSION 0x00097710 silently ignored if followed by zero value.
   1929    */
   1930   MHD_OPTION_CONNECTION_MEMORY_INCREMENT = 21,
   1931 
   1932   /**
   1933    * Use a callback to determine which X.509 certificate should be
   1934    * used for a given HTTPS connection.  This option should be
   1935    * followed by a argument of type `gnutls_certificate_retrieve_function2 *`.
   1936    * This option provides an
   1937    * alternative to #MHD_OPTION_HTTPS_MEM_KEY,
   1938    * #MHD_OPTION_HTTPS_MEM_CERT.  You must use this version if
   1939    * multiple domains are to be hosted at the same IP address using
   1940    * TLS's Server Name Indication (SNI) extension.  In this case,
   1941    * the callback is expected to select the correct certificate
   1942    * based on the SNI information provided.  The callback is expected
   1943    * to access the SNI data using `gnutls_server_name_get()`.
   1944    * Using this option requires GnuTLS 3.0 or higher.
   1945    */
   1946   MHD_OPTION_HTTPS_CERT_CALLBACK = 22,
   1947 
   1948   /**
   1949    * When using #MHD_USE_TCP_FASTOPEN, this option changes the default TCP
   1950    * fastopen queue length of 50.  Note that having a larger queue size can
   1951    * cause resource exhaustion attack as the TCP stack has to now allocate
   1952    * resources for the SYN packet along with its DATA.  This option should be
   1953    * followed by an `unsigned int` argument.
   1954    */
   1955   MHD_OPTION_TCP_FASTOPEN_QUEUE_SIZE = 23,
   1956 
   1957   /**
   1958    * Memory pointer for the Diffie-Hellman parameters (dh.pem) to be used by the
   1959    * HTTPS daemon for key exchange.
   1960    * This option must be followed by a `const char *` argument.
   1961    */
   1962   MHD_OPTION_HTTPS_MEM_DHPARAMS = 24,
   1963 
   1964   /**
   1965    * If present and set to true, allow reusing address:port socket
   1966    * (by using SO_REUSEPORT on most platform, or platform-specific ways).
   1967    * If present and set to false, disallow reusing address:port socket
   1968    * (does nothing on most platform, but uses SO_EXCLUSIVEADDRUSE on Windows).
   1969    * This option must be followed by a `unsigned int` argument.
   1970    */
   1971   MHD_OPTION_LISTENING_ADDRESS_REUSE = 25,
   1972 
   1973   /**
   1974    * Memory pointer for a password that decrypts the private key (key.pem)
   1975    * to be used by the HTTPS daemon. This option should be followed by a
   1976    * `const char *` argument.
   1977    * This should be used in conjunction with #MHD_OPTION_HTTPS_MEM_KEY.
   1978    * @sa ::MHD_FEATURE_HTTPS_KEY_PASSWORD
   1979    */
   1980   MHD_OPTION_HTTPS_KEY_PASSWORD = 26,
   1981 
   1982   /**
   1983    * Register a function that should be called whenever a connection is
   1984    * started or closed.
   1985    *
   1986    * This option should be followed by TWO pointers.  First a pointer
   1987    * to a function of type #MHD_NotifyConnectionCallback and second a
   1988    * pointer to a closure to pass to the request completed callback.
   1989    * The second pointer may be NULL.
   1990    */
   1991   MHD_OPTION_NOTIFY_CONNECTION = 27,
   1992 
   1993   /**
   1994    * Allow to change maximum length of the queue of pending connections on
   1995    * listen socket. If not present than default platform-specific SOMAXCONN
   1996    * value is used. This option should be followed by an `unsigned int`
   1997    * argument.
   1998    */
   1999   MHD_OPTION_LISTEN_BACKLOG_SIZE = 28,
   2000 
   2001   /**
   2002    * If set to 1 - be strict about the protocol.  Use -1 to be
   2003    * as tolerant as possible.
   2004    *
   2005    * The more flexible option #MHD_OPTION_CLIENT_DISCIPLINE_LVL is recommended
   2006    * instead of this option.
   2007    *
   2008    * The values mapping table:
   2009    * #MHD_OPTION_STRICT_FOR_CLIENT | #MHD_OPTION_CLIENT_DISCIPLINE_LVL
   2010    * -----------------------------:|:---------------------------------
   2011    * 1                             | 1
   2012    * 0                             | 0
   2013    * -1                            | -3
   2014    *
   2015    * This option should be followed by an `int` argument.
   2016    * @sa #MHD_OPTION_CLIENT_DISCIPLINE_LVL
   2017    */
   2018   MHD_OPTION_STRICT_FOR_CLIENT = 29,
   2019 
   2020   /**
   2021    * This should be a pointer to callback of type
   2022    * gnutls_psk_server_credentials_function that will be given to
   2023    * gnutls_psk_set_server_credentials_function. It is used to
   2024    * retrieve the shared key for a given username.
   2025    */
   2026   MHD_OPTION_GNUTLS_PSK_CRED_HANDLER = 30,
   2027 
   2028   /**
   2029    * Use a callback to determine which X.509 certificate should be
   2030    * used for a given HTTPS connection.  This option should be
   2031    * followed by a argument of type `gnutls_certificate_retrieve_function3 *`.
   2032    * This option provides an
   2033    * alternative/extension to #MHD_OPTION_HTTPS_CERT_CALLBACK.
   2034    * You must use this version if you want to use OCSP stapling.
   2035    * Using this option requires GnuTLS 3.6.3 or higher.
   2036    */
   2037   MHD_OPTION_HTTPS_CERT_CALLBACK2 = 31,
   2038 
   2039   /**
   2040    * Allows the application to disable certain sanity precautions
   2041    * in MHD. With these, the client can break the HTTP protocol,
   2042    * so this should never be used in production. The options are,
   2043    * however, useful for testing HTTP clients against "broken"
   2044    * server implementations.
   2045    * This argument must be followed by an "unsigned int", corresponding
   2046    * to an `enum MHD_DisableSanityCheck`.
   2047    */
   2048   MHD_OPTION_SERVER_INSANITY = 32,
   2049 
   2050   /**
   2051    * If followed by value '1' informs MHD that SIGPIPE is suppressed or
   2052    * handled by application. Allows MHD to use network functions that could
   2053    * generate SIGPIPE, like `sendfile()`.
   2054    * Valid only for daemons without #MHD_USE_INTERNAL_POLLING_THREAD as
   2055    * MHD automatically suppresses SIGPIPE for threads started by MHD.
   2056    * This option should be followed by an `int` argument.
   2057    * @note Available since #MHD_VERSION 0x00097205
   2058    */
   2059   MHD_OPTION_SIGPIPE_HANDLED_BY_APP = 33,
   2060 
   2061   /**
   2062    * If followed by 'int' with value '1' disables usage of ALPN for TLS
   2063    * connections even if supported by TLS library.
   2064    * Valid only for daemons with #MHD_USE_TLS.
   2065    * This option should be followed by an `int` argument.
   2066    * @note Available since #MHD_VERSION 0x00097207
   2067    */
   2068   MHD_OPTION_TLS_NO_ALPN = 34,
   2069 
   2070   /**
   2071    * Memory pointer for the random values to be used by the Digest
   2072    * Auth module. This option should be followed by two arguments.
   2073    * First an integer of type `size_t` which specifies the size
   2074    * of the buffer pointed to by the second argument in bytes.
   2075    * The recommended size is between 8 and 32. If size is four or less
   2076    * then security could be lowered. Sizes more then 32 (or, probably
   2077    * more than 16 - debatable) will not increase security.
   2078    * An internal copy of the buffer will be made, the data do not
   2079    * need to be static.
   2080    * @sa #MHD_OPTION_DIGEST_AUTH_RANDOM
   2081    * @note Available since #MHD_VERSION 0x00097701
   2082    */
   2083   MHD_OPTION_DIGEST_AUTH_RANDOM_COPY = 35,
   2084 
   2085   /**
   2086    * Allow to controls the scope of validity of MHD-generated nonces.
   2087    * This regulates how "nonces" are generated and how "nonces" are checked by
   2088    * #MHD_digest_auth_check3() and similar functions.
   2089    * This option should be followed by an 'unsigned int` argument with value
   2090    * formed as bitwise OR combination of #MHD_DAuthBindNonce values.
   2091    * When not specified, default value #MHD_DAUTH_BIND_NONCE_NONE is used.
   2092    * @note Available since #MHD_VERSION 0x00097701
   2093    */
   2094   MHD_OPTION_DIGEST_AUTH_NONCE_BIND_TYPE = 36,
   2095 
   2096   /**
   2097    * Memory pointer to a `const char *` specifying the GnuTLS priorities to be
   2098    * appended to default priorities.
   2099    * This allow some specific options to be enabled/disabled, while leaving
   2100    * the rest of the settings to their defaults.
   2101    * The string does not have to start with a colon ':' character.
   2102    * See #MHD_OPTION_HTTPS_PRIORITIES description for details of automatic
   2103    * default priorities.
   2104    * @note Available since #MHD_VERSION 0x00097701
   2105    */
   2106   MHD_OPTION_HTTPS_PRIORITIES_APPEND = 37,
   2107 
   2108   /**
   2109    * Sets specified client discipline level (i.e. HTTP protocol parsing
   2110    * strictness level).
   2111    *
   2112    * The following basic values are supported:
   2113    *  0 - default MHD level, a balance between extra security and broader
   2114    *      compatibility, as allowed by RFCs for HTTP servers;
   2115    *  1 - more strict protocol interpretation, within the limits set by
   2116    *      RFCs for HTTP servers;
   2117    * -1 - more lenient protocol interpretation, within the limits set by
   2118    *      RFCs for HTTP servers.
   2119    * The following extended values could be used as well:
   2120    *  2 - stricter protocol interpretation, even stricter then allowed
   2121    *      by RFCs for HTTP servers, however it should be absolutely compatible
   2122    *      with clients following at least RFCs' "MUST" type of requirements
   2123    *      for HTTP clients;
   2124    *  3 - strictest protocol interpretation, even stricter then allowed
   2125    *      by RFCs for HTTP servers, however it should be absolutely compatible
   2126    *      with clients following RFCs' "SHOULD" and "MUST" types of requirements
   2127    *      for HTTP clients;
   2128    * -2 - more relaxed protocol interpretation, violating RFCs' "SHOULD" type
   2129    *      of requirements for HTTP servers;
   2130    * -3 - the most flexible protocol interpretation, beyond RFCs' "MUST" type of
   2131    *      requirements for HTTP server.
   2132    * Values higher than "3" or lower than "-3" are interpreted as "3" or "-3"
   2133    * respectively.
   2134    *
   2135    * Higher values are more secure, lower values are more compatible with
   2136    * various HTTP clients.
   2137    *
   2138    * The default value ("0") could be used in most cases.
   2139    * Value "1" is suitable for highly loaded public servers.
   2140    * Values "2" and "3" are generally recommended only for testing of HTTP
   2141    * clients against MHD.
   2142    * Value "2" may be used for security-centric application, however it is
   2143    * slight violation of RFCs' requirements.
   2144    * Negative values are not recommended for public servers.
   2145    * Values "-1" and "-2" could be used for servers in isolated environment.
   2146    * Value "-3" is not recommended unless it is absolutely necessary to
   2147    * communicate with some client(s) with badly broken HTTP implementation.
   2148    *
   2149    * This option should be followed by an `int` argument.
   2150    * @note Available since #MHD_VERSION 0x00097701
   2151    */
   2152   MHD_OPTION_CLIENT_DISCIPLINE_LVL = 38,
   2153 
   2154   /**
   2155    * Specifies value of FD_SETSIZE used by application.  Only For external
   2156    * polling modes (without MHD internal threads).
   2157    * Some platforms (FreeBSD, Solaris, W32 etc.) allow overriding of FD_SETSIZE
   2158    * value.  When polling by select() is used, MHD rejects sockets with numbers
   2159    * equal or higher than FD_SETSIZE.  If this option is used, MHD treats this
   2160    * value as a limitation for socket number instead of FD_SETSIZE value which
   2161    * was used for building MHD.
   2162    * When external polling is used with #MHD_get_fdset2() (or #MHD_get_fdset()
   2163    * macro) and #MHD_run_from_select() interfaces, it is recommended to always
   2164    * use this option.
   2165    * It is safe to use this option on platforms with fixed FD_SETSIZE (like
   2166    * GNU/Linux) if system value of FD_SETSIZE is used as the argument.
   2167    * Can be used only for daemons without #MHD_USE_INTERNAL_POLLING_THREAD, i.e.
   2168    * only when external sockets polling is used.
   2169    * On W32 it is silently ignored, as W32 does not limit the socket number in
   2170    * fd_sets.
   2171    * This option should be followed by a positive 'int' argument.
   2172    * @note Available since #MHD_VERSION 0x00097705
   2173    */
   2174   MHD_OPTION_APP_FD_SETSIZE = 39,
   2175 
   2176   /**
   2177    * Bind daemon to the supplied 'struct sockaddr'.  This option should
   2178    * be followed by two parameters: 'socklen_t' the size of memory at the next
   2179    * pointer and the pointer 'const struct sockaddr *'.
   2180    * Note: the order of the arguments is not the same as for system bind() and
   2181    * other network functions.
   2182    * If #MHD_USE_IPv6 is specified, the 'struct sockaddr*' should
   2183    * point to a 'struct sockaddr_in6'.
   2184    * The socket domain (protocol family) is detected from provided
   2185    * 'struct sockaddr'. IP, IPv6 and UNIX sockets are supported (if supported
   2186    * by the platform). Other types may work occasionally.
   2187    * Silently ignored if followed by zero size and NULL pointer.
   2188    * @note Available since #MHD_VERSION 0x00097706
   2189    */
   2190   MHD_OPTION_SOCK_ADDR_LEN = 40
   2191   ,
   2192   /**
   2193    * Default nonce timeout value used for Digest Auth.
   2194    * This option should be followed by an 'unsigned int' argument.
   2195    * Silently ignored if followed by zero value.
   2196    * @see #MHD_digest_auth_check3(), MHD_digest_auth_check_digest3()
   2197    * @note Available since #MHD_VERSION 0x00097709
   2198    */
   2199   MHD_OPTION_DIGEST_AUTH_DEFAULT_NONCE_TIMEOUT = 41
   2200   ,
   2201   /**
   2202    * Default maximum nc (nonce count) value used for Digest Auth.
   2203    * This option should be followed by an 'uint32_t' argument.
   2204    * Silently ignored if followed by zero value.
   2205    * @see #MHD_digest_auth_check3(), MHD_digest_auth_check_digest3()
   2206    * @note Available since #MHD_VERSION 0x00097709
   2207    */
   2208   MHD_OPTION_DIGEST_AUTH_DEFAULT_MAX_NC = 42
   2209   ,
   2210   /**
   2211    * Default maximum nc (nonce count) value used for Digest Auth.
   2212    * This option must be followed by an 'int' argument.
   2213    * If followed by '0' (default) then:
   2214    * + requests are rejected if request URI has binary zero (the result
   2215    *   of %00 decoding) in the path part of the URI.
   2216    * If followed by '1' then:
   2217    * + binary zero is allowed in request URI path;
   2218    * + #MHD_AccessHandlerCallback called with NULL in @a url parameter when
   2219    *   request URI path has binary zero, the full @a url is available only
   2220    *   via #MHD_get_connection_URI_path_n()
   2221    * If followed by '2' (unsafe!) then:
   2222    * + binary zero is allowed in request URI path;
   2223    * + #MHD_AccessHandlerCallback called with truncated (unsafe!) @a url
   2224    *   parameter when request URI path has binary zero.
   2225    * @see #MHD_get_connection_URI_path_n()
   2226    * @note Available since #MHD_VERSION 0x01000201
   2227    */
   2228   MHD_OPTION_ALLOW_BIN_ZERO_IN_URI_PATH = 43
   2229 
   2230 } _MHD_FIXED_ENUM;
   2231 
   2232 
   2233 /**
   2234  * Bitfield for the #MHD_OPTION_SERVER_INSANITY specifying
   2235  * which santiy checks should be disabled.
   2236  */
   2237 enum MHD_DisableSanityCheck
   2238 {
   2239   /**
   2240    * All sanity checks are enabled.
   2241    */
   2242   MHD_DSC_SANE = 0
   2243 
   2244 } _MHD_FIXED_FLAGS_ENUM;
   2245 
   2246 
   2247 /**
   2248  * Entry in an #MHD_OPTION_ARRAY.
   2249  */
   2250 struct MHD_OptionItem
   2251 {
   2252   /**
   2253    * Which option is being given.  Use #MHD_OPTION_END
   2254    * to terminate the array.
   2255    */
   2256   enum MHD_OPTION option;
   2257 
   2258   /**
   2259    * Option value (for integer arguments, and for options requiring
   2260    * two pointer arguments); should be 0 for options that take no
   2261    * arguments or only a single pointer argument.
   2262    */
   2263   intptr_t value;
   2264 
   2265   /**
   2266    * Pointer option value (use NULL for options taking no arguments
   2267    * or only an integer option).
   2268    */
   2269   void *ptr_value;
   2270 
   2271 };
   2272 
   2273 
   2274 /**
   2275  * The `enum MHD_ValueKind` specifies the source of
   2276  * the key-value pairs in the HTTP protocol.
   2277  */
   2278 enum MHD_ValueKind
   2279 {
   2280 
   2281   /**
   2282    * Response header
   2283    * @deprecated
   2284    */
   2285   MHD_RESPONSE_HEADER_KIND = 0,
   2286 #define MHD_RESPONSE_HEADER_KIND \
   2287         _MHD_DEPR_IN_MACRO ( \
   2288           "Value MHD_RESPONSE_HEADER_KIND is deprecated and not used") \
   2289         MHD_RESPONSE_HEADER_KIND
   2290 
   2291   /**
   2292    * HTTP header (request/response).
   2293    */
   2294   MHD_HEADER_KIND = 1,
   2295 
   2296   /**
   2297    * Cookies.  Note that the original HTTP header containing
   2298    * the cookie(s) will still be available and intact.
   2299    */
   2300   MHD_COOKIE_KIND = 2,
   2301 
   2302   /**
   2303    * POST data.  This is available only if a content encoding
   2304    * supported by MHD is used (currently only URL encoding),
   2305    * and only if the posted content fits within the available
   2306    * memory pool.  Note that in that case, the upload data
   2307    * given to the #MHD_AccessHandlerCallback will be
   2308    * empty (since it has already been processed).
   2309    */
   2310   MHD_POSTDATA_KIND = 4,
   2311 
   2312   /**
   2313    * GET (URI) arguments.
   2314    */
   2315   MHD_GET_ARGUMENT_KIND = 8,
   2316 
   2317   /**
   2318    * HTTP footer (only for HTTP 1.1 chunked encodings).
   2319    */
   2320   MHD_FOOTER_KIND = 16
   2321 } _MHD_FIXED_ENUM;
   2322 
   2323 
   2324 /**
   2325  * The `enum MHD_RequestTerminationCode` specifies reasons
   2326  * why a request has been terminated (or completed).
   2327  * @ingroup request
   2328  */
   2329 enum MHD_RequestTerminationCode
   2330 {
   2331 
   2332   /**
   2333    * We finished sending the response.
   2334    * @ingroup request
   2335    */
   2336   MHD_REQUEST_TERMINATED_COMPLETED_OK = 0,
   2337 
   2338   /**
   2339    * Error handling the connection (resources
   2340    * exhausted, application error accepting request,
   2341    * decrypt error (for HTTPS), connection died when
   2342    * sending the response etc.)
   2343    * @ingroup request
   2344    */
   2345   MHD_REQUEST_TERMINATED_WITH_ERROR = 1,
   2346 
   2347   /**
   2348    * No activity on the connection for the number
   2349    * of seconds specified using
   2350    * #MHD_OPTION_CONNECTION_TIMEOUT.
   2351    * @ingroup request
   2352    */
   2353   MHD_REQUEST_TERMINATED_TIMEOUT_REACHED = 2,
   2354 
   2355   /**
   2356    * We had to close the session since MHD was being
   2357    * shut down.
   2358    * @ingroup request
   2359    */
   2360   MHD_REQUEST_TERMINATED_DAEMON_SHUTDOWN = 3,
   2361 
   2362   /**
   2363    * We tried to read additional data, but the connection became broken or
   2364    * the other side hard closed the connection.
   2365    * This error is similar to #MHD_REQUEST_TERMINATED_WITH_ERROR, but
   2366    * specific to the case where the connection died before request completely
   2367    * received.
   2368    * @ingroup request
   2369    */
   2370   MHD_REQUEST_TERMINATED_READ_ERROR = 4,
   2371 
   2372   /**
   2373    * The client terminated the connection by closing the socket
   2374    * for writing (TCP half-closed) while still sending request.
   2375    * @ingroup request
   2376    */
   2377   MHD_REQUEST_TERMINATED_CLIENT_ABORT = 5
   2378 
   2379 } _MHD_FIXED_ENUM;
   2380 
   2381 
   2382 /**
   2383  * The `enum MHD_ConnectionNotificationCode` specifies types
   2384  * of connection notifications.
   2385  * @ingroup request
   2386  */
   2387 enum MHD_ConnectionNotificationCode
   2388 {
   2389 
   2390   /**
   2391    * A new connection has been started.
   2392    * @ingroup request
   2393    */
   2394   MHD_CONNECTION_NOTIFY_STARTED = 0,
   2395 
   2396   /**
   2397    * A connection is closed.
   2398    * @ingroup request
   2399    */
   2400   MHD_CONNECTION_NOTIFY_CLOSED = 1
   2401 
   2402 } _MHD_FIXED_ENUM;
   2403 
   2404 
   2405 /**
   2406  * Information about a connection.
   2407  */
   2408 union MHD_ConnectionInfo
   2409 {
   2410 
   2411   /**
   2412    * Cipher algorithm used, of type "enum gnutls_cipher_algorithm".
   2413    */
   2414   int /* enum gnutls_cipher_algorithm */ cipher_algorithm;
   2415 
   2416   /**
   2417    * Protocol used, of type "enum gnutls_protocol".
   2418    */
   2419   int /* enum gnutls_protocol */ protocol;
   2420 
   2421   /**
   2422    * The suspended status of a connection.
   2423    */
   2424   int /* MHD_YES or MHD_NO */ suspended;
   2425 
   2426   /**
   2427    * Amount of second that connection could spend in idle state
   2428    * before automatically disconnected.
   2429    * Zero for no timeout (unlimited idle time).
   2430    */
   2431   unsigned int connection_timeout;
   2432 
   2433   /**
   2434    * HTTP status queued with the response, for #MHD_CONNECTION_INFO_HTTP_STATUS.
   2435    */
   2436   unsigned int http_status;
   2437 
   2438   /**
   2439    * Connect socket
   2440    */
   2441   MHD_socket connect_fd;
   2442 
   2443   /**
   2444    * Size of the client's HTTP header.
   2445    * It includes the request line, all request headers, the header section
   2446    * terminating empty line, with all CRLF (or LF) characters.
   2447    */
   2448   size_t header_size;
   2449 
   2450   /**
   2451    * GNUtls session handle, of type "gnutls_session_t".
   2452    */
   2453   void * /* gnutls_session_t */ tls_session;
   2454 
   2455   /**
   2456    * GNUtls client certificate handle, of type "gnutls_x509_crt_t".
   2457    */
   2458   void * /* gnutls_x509_crt_t */ client_cert;
   2459 
   2460   /**
   2461    * Address information for the client.
   2462    */
   2463   struct sockaddr *client_addr;
   2464 
   2465   /**
   2466    * Which daemon manages this connection (useful in case there are many
   2467    * daemons running).
   2468    */
   2469   struct MHD_Daemon *daemon;
   2470 
   2471   /**
   2472    * Socket-specific client context.  Points to the same address as
   2473    * the "socket_context" of the #MHD_NotifyConnectionCallback.
   2474    */
   2475   void *socket_context;
   2476 };
   2477 
   2478 
   2479 /**
   2480  * I/O vector type. Provided for use with #MHD_create_response_from_iovec().
   2481  * @note Available since #MHD_VERSION 0x00097204
   2482  */
   2483 struct MHD_IoVec
   2484 {
   2485   /**
   2486    * The pointer to the memory region for I/O.
   2487    */
   2488   const void *iov_base;
   2489 
   2490   /**
   2491    * The size in bytes of the memory region for I/O.
   2492    */
   2493   size_t iov_len;
   2494 };
   2495 
   2496 
   2497 /**
   2498  * Values of this enum are used to specify what
   2499  * information about a connection is desired.
   2500  * @ingroup request
   2501  */
   2502 enum MHD_ConnectionInfoType
   2503 {
   2504   /**
   2505    * What cipher algorithm is being used.
   2506    * Takes no extra arguments.
   2507    * @ingroup request
   2508    */
   2509   MHD_CONNECTION_INFO_CIPHER_ALGO,
   2510 
   2511   /**
   2512    *
   2513    * Takes no extra arguments.
   2514    * @ingroup request
   2515    */
   2516   MHD_CONNECTION_INFO_PROTOCOL,
   2517 
   2518   /**
   2519    * Obtain IP address of the client.  Takes no extra arguments.
   2520    * Returns essentially a `struct sockaddr **` (since the API returns
   2521    * a `union MHD_ConnectionInfo *` and that union contains a `struct
   2522    * sockaddr *`).
   2523    * @ingroup request
   2524    */
   2525   MHD_CONNECTION_INFO_CLIENT_ADDRESS,
   2526 
   2527   /**
   2528    * Get the gnuTLS session handle.
   2529    * @ingroup request
   2530    */
   2531   MHD_CONNECTION_INFO_GNUTLS_SESSION,
   2532 
   2533   /**
   2534    * Get the gnuTLS client certificate handle.  Dysfunctional (never
   2535    * implemented, deprecated).  Use #MHD_CONNECTION_INFO_GNUTLS_SESSION
   2536    * to get the `gnutls_session_t` and then call
   2537    * gnutls_certificate_get_peers().
   2538    */
   2539   MHD_CONNECTION_INFO_GNUTLS_CLIENT_CERT,
   2540 
   2541   /**
   2542    * Get the `struct MHD_Daemon *` responsible for managing this connection.
   2543    * @ingroup request
   2544    */
   2545   MHD_CONNECTION_INFO_DAEMON,
   2546 
   2547   /**
   2548    * Request the file descriptor for the connection socket.
   2549    * MHD sockets are always in non-blocking mode.
   2550    * No extra arguments should be passed.
   2551    * @ingroup request
   2552    */
   2553   MHD_CONNECTION_INFO_CONNECTION_FD,
   2554 
   2555   /**
   2556    * Returns the client-specific pointer to a `void *` that was (possibly)
   2557    * set during a #MHD_NotifyConnectionCallback when the socket was
   2558    * first accepted.
   2559    * Note that this is NOT the same as the "req_cls" argument of
   2560    * the #MHD_AccessHandlerCallback. The "req_cls" is fresh for each
   2561    * HTTP request, while the "socket_context" is fresh for each socket.
   2562    */
   2563   MHD_CONNECTION_INFO_SOCKET_CONTEXT,
   2564 
   2565   /**
   2566    * Check whether the connection is suspended.
   2567    * @ingroup request
   2568    */
   2569   MHD_CONNECTION_INFO_CONNECTION_SUSPENDED,
   2570 
   2571   /**
   2572    * Get connection timeout
   2573    * @ingroup request
   2574    */
   2575   MHD_CONNECTION_INFO_CONNECTION_TIMEOUT,
   2576 
   2577   /**
   2578    * Return length of the client's HTTP request header.
   2579    * @ingroup request
   2580    */
   2581   MHD_CONNECTION_INFO_REQUEST_HEADER_SIZE,
   2582 
   2583   /**
   2584    * Return HTTP status queued with the response. NULL
   2585    * if no HTTP response has been queued yet.
   2586    */
   2587   MHD_CONNECTION_INFO_HTTP_STATUS
   2588 
   2589 } _MHD_FIXED_ENUM;
   2590 
   2591 
   2592 /**
   2593  * Values of this enum are used to specify what
   2594  * information about a daemon is desired.
   2595  */
   2596 enum MHD_DaemonInfoType
   2597 {
   2598   /**
   2599    * No longer supported (will return NULL).
   2600    */
   2601   MHD_DAEMON_INFO_KEY_SIZE,
   2602 
   2603   /**
   2604    * No longer supported (will return NULL).
   2605    */
   2606   MHD_DAEMON_INFO_MAC_KEY_SIZE,
   2607 
   2608   /**
   2609    * Request the file descriptor for the listening socket.
   2610    * No extra arguments should be passed.
   2611    */
   2612   MHD_DAEMON_INFO_LISTEN_FD,
   2613 
   2614   /**
   2615    * Request the file descriptor for the "external" sockets polling
   2616    * when 'epoll' mode is used.
   2617    * No extra arguments should be passed.
   2618    *
   2619    * Waiting on epoll FD must not block longer than value
   2620    * returned by #MHD_get_timeout() otherwise connections
   2621    * will "hung" with unprocessed data in network buffers
   2622    * and timed-out connections will not be closed.
   2623    *
   2624    * @sa #MHD_get_timeout(), #MHD_run()
   2625    */
   2626   MHD_DAEMON_INFO_EPOLL_FD_LINUX_ONLY,
   2627   MHD_DAEMON_INFO_EPOLL_FD = MHD_DAEMON_INFO_EPOLL_FD_LINUX_ONLY,
   2628 
   2629   /**
   2630    * Request the number of current connections handled by the daemon.
   2631    * No extra arguments should be passed.
   2632    * Note: when using MHD in "external" polling mode, this type of request
   2633    * could be used only when #MHD_run()/#MHD_run_from_select is not
   2634    * working in other thread at the same time.
   2635    */
   2636   MHD_DAEMON_INFO_CURRENT_CONNECTIONS,
   2637 
   2638   /**
   2639    * Request the daemon flags.
   2640    * No extra arguments should be passed.
   2641    * Note: flags may differ from original 'flags' specified for
   2642    * daemon, especially if #MHD_USE_AUTO was set.
   2643    */
   2644   MHD_DAEMON_INFO_FLAGS,
   2645 
   2646   /**
   2647    * Request the port number of daemon's listen socket.
   2648    * No extra arguments should be passed.
   2649    * Note: if port '0' was specified for #MHD_start_daemon(), returned
   2650    * value will be real port number.
   2651    */
   2652   MHD_DAEMON_INFO_BIND_PORT
   2653 } _MHD_FIXED_ENUM;
   2654 
   2655 
   2656 /**
   2657  * Callback for serious error condition. The default action is to print
   2658  * an error message and `abort()`.
   2659  *
   2660  * @param cls user specified value
   2661  * @param file where the error occurred, may be NULL if MHD was built without
   2662  *             messages support
   2663  * @param line where the error occurred
   2664  * @param reason error detail, may be NULL
   2665  * @ingroup logging
   2666  */
   2667 typedef void
   2668 (*MHD_PanicCallback) (void *cls,
   2669                       const char *file,
   2670                       unsigned int line,
   2671                       const char *reason);
   2672 
   2673 /**
   2674  * Allow or deny a client to connect.
   2675  *
   2676  * @param cls closure
   2677  * @param addr address information from the client
   2678  * @param addrlen length of @a addr
   2679  * @return #MHD_YES if connection is allowed, #MHD_NO if not
   2680  */
   2681 typedef enum MHD_Result
   2682 (*MHD_AcceptPolicyCallback)(void *cls,
   2683                             const struct sockaddr *addr,
   2684                             socklen_t addrlen);
   2685 
   2686 
   2687 /**
   2688  * A client has requested the given @a url using the given @a method
   2689  * (#MHD_HTTP_METHOD_GET, #MHD_HTTP_METHOD_PUT, #MHD_HTTP_METHOD_DELETE,
   2690  * #MHD_HTTP_METHOD_POST, etc).
   2691  *
   2692  * The callback must call MHD function MHD_queue_response() to provide content
   2693  * to give back to the client and return an HTTP status code (i.e.
   2694  * #MHD_HTTP_OK, #MHD_HTTP_NOT_FOUND, etc.). The response can be created
   2695  * in this callback or prepared in advance.
   2696  * Alternatively, callback may call MHD_suspend_connection() to temporarily
   2697  * suspend data processing for this connection.
   2698  *
   2699  * As soon as response is provided this callback will not be called anymore
   2700  * for the current request.
   2701  *
   2702  * For each HTTP request this callback is called several times:
   2703  * * after request headers are fully received and decoded,
   2704  * * for each received part of request body (optional, if request has body),
   2705  * * when request is fully received.
   2706  *
   2707  * If response is provided before request is fully received, the rest
   2708  * of the request is discarded and connection is automatically closed
   2709  * after sending response.
   2710  *
   2711  * If the request is fully received, but response hasn't been provided and
   2712  * connection is not suspended, the callback can be called again immediately.
   2713  *
   2714  * The response cannot be queued when this callback is called to process
   2715  * the client upload data (when @a upload_data is not NULL).
   2716  *
   2717  * @param cls argument given together with the function
   2718  *        pointer when the handler was registered with MHD
   2719  * @param connection the connection handle
   2720  * @param url the requested url, can be truncated or can be NULL, depending
   2721  *        on #MHD_OPTION_ALLOW_BIN_ZERO_IN_URI_PATH option,
   2722  *        see #MHD_get_connection_URI_path_n()
   2723  * @param method the HTTP method used (#MHD_HTTP_METHOD_GET,
   2724  *        #MHD_HTTP_METHOD_PUT, etc.)
   2725  * @param version the HTTP version string (i.e.
   2726  *        #MHD_HTTP_VERSION_1_1)
   2727  * @param upload_data the data being uploaded (excluding HEADERS,
   2728  *        for a POST that fits into memory and that is encoded
   2729  *        with a supported encoding, the POST data will NOT be
   2730  *        given in upload_data and is instead available as
   2731  *        part of #MHD_get_connection_values; very large POST
   2732  *        data *will* be made available incrementally in
   2733  *        @a upload_data)
   2734  * @param[in,out] upload_data_size set initially to the size of the
   2735  *        @a upload_data provided; the method must update this
   2736  *        value to the number of bytes NOT processed;
   2737  * @param[in,out] req_cls pointer that the callback can set to some
   2738  *        address and that will be preserved by MHD for future
   2739  *        calls for this request; since the access handler may
   2740  *        be called many times (i.e., for a PUT/POST operation
   2741  *        with plenty of upload data) this allows the application
   2742  *        to easily associate some request-specific state.
   2743  *        If necessary, this state can be cleaned up in the
   2744  *        global #MHD_RequestCompletedCallback (which
   2745  *        can be set with the #MHD_OPTION_NOTIFY_COMPLETED).
   2746  *        Initially, `*req_cls` will be NULL.
   2747  * @return #MHD_YES if the connection was handled successfully,
   2748  *         #MHD_NO if the socket must be closed due to a serious
   2749  *         error while handling the request
   2750  *
   2751  * @sa #MHD_queue_response(), #MHD_get_connection_URI_path_n()
   2752  */
   2753 typedef enum MHD_Result
   2754 (*MHD_AccessHandlerCallback)(void *cls,
   2755                              struct MHD_Connection *connection,
   2756                              const char *url,
   2757                              const char *method,
   2758                              const char *version,
   2759                              const char *upload_data,
   2760                              size_t *upload_data_size,
   2761                              void **req_cls);
   2762 
   2763 
   2764 /**
   2765  * Signature of the callback used by MHD to notify the
   2766  * application about completed requests.
   2767  *
   2768  * @param cls client-defined closure
   2769  * @param connection connection handle
   2770  * @param req_cls value as set by the last call to
   2771  *        the #MHD_AccessHandlerCallback
   2772  * @param toe reason for request termination
   2773  * @see #MHD_OPTION_NOTIFY_COMPLETED
   2774  * @ingroup request
   2775  */
   2776 typedef void
   2777 (*MHD_RequestCompletedCallback) (void *cls,
   2778                                  struct MHD_Connection *connection,
   2779                                  void **req_cls,
   2780                                  enum MHD_RequestTerminationCode toe);
   2781 
   2782 
   2783 /**
   2784  * Signature of the callback used by MHD to notify the
   2785  * application about started/stopped connections
   2786  *
   2787  * @param cls client-defined closure
   2788  * @param connection connection handle
   2789  * @param socket_context socket-specific pointer where the
   2790  *                       client can associate some state specific
   2791  *                       to the TCP connection; note that this is
   2792  *                       different from the "req_cls" which is per
   2793  *                       HTTP request.  The client can initialize
   2794  *                       during #MHD_CONNECTION_NOTIFY_STARTED and
   2795  *                       cleanup during #MHD_CONNECTION_NOTIFY_CLOSED
   2796  *                       and access in the meantime using
   2797  *                       #MHD_CONNECTION_INFO_SOCKET_CONTEXT.
   2798  * @param toe reason for connection notification
   2799  * @see #MHD_OPTION_NOTIFY_CONNECTION
   2800  * @ingroup request
   2801  */
   2802 typedef void
   2803 (*MHD_NotifyConnectionCallback) (void *cls,
   2804                                  struct MHD_Connection *connection,
   2805                                  void **socket_context,
   2806                                  enum MHD_ConnectionNotificationCode toe);
   2807 
   2808 
   2809 /**
   2810  * Iterator over key-value pairs.  This iterator
   2811  * can be used to iterate over all of the cookies,
   2812  * headers, or POST-data fields of a request, and
   2813  * also to iterate over the headers that have been
   2814  * added to a response.
   2815  *
   2816  * @param cls closure
   2817  * @param kind kind of the header we are looking at
   2818  * @param key key for the value, can be an empty string
   2819  * @param value corresponding value, can be NULL
   2820  * @return #MHD_YES to continue iterating,
   2821  *         #MHD_NO to abort the iteration
   2822  * @ingroup request
   2823  */
   2824 typedef enum MHD_Result
   2825 (*MHD_KeyValueIterator)(void *cls,
   2826                         enum MHD_ValueKind kind,
   2827                         const char *key,
   2828                         const char *value);
   2829 
   2830 
   2831 /**
   2832  * Iterator over key-value pairs with size parameters.
   2833  * This iterator can be used to iterate over all of
   2834  * the cookies, headers, or POST-data fields of a
   2835  * request, and also to iterate over the headers that
   2836  * have been added to a response.
   2837  * @note Available since #MHD_VERSION 0x00096303
   2838  *
   2839  * @param cls closure
   2840  * @param kind kind of the header we are looking at
   2841  * @param key key for the value, can be an empty string
   2842  * @param value corresponding value, can be NULL
   2843  * @param value_size number of bytes in @a value;
   2844  *                   for C-strings, the length excludes the 0-terminator
   2845  * @return #MHD_YES to continue iterating,
   2846  *         #MHD_NO to abort the iteration
   2847  * @ingroup request
   2848  */
   2849 typedef enum MHD_Result
   2850 (*MHD_KeyValueIteratorN)(void *cls,
   2851                          enum MHD_ValueKind kind,
   2852                          const char *key,
   2853                          size_t key_size,
   2854                          const char *value,
   2855                          size_t value_size);
   2856 
   2857 
   2858 /**
   2859  * Callback used by libmicrohttpd in order to obtain content.
   2860  *
   2861  * The callback is to copy at most @a max bytes of content into @a buf.
   2862  * The total number of bytes that has been placed into @a buf should be
   2863  * returned.
   2864  *
   2865  * Note that returning zero will cause libmicrohttpd to try again.
   2866  * Thus, returning zero should only be used in conjunction
   2867  * with MHD_suspend_connection() to avoid busy waiting.
   2868  *
   2869  * @param cls extra argument to the callback
   2870  * @param pos position in the datastream to access;
   2871  *        note that if a `struct MHD_Response` object is re-used,
   2872  *        it is possible for the same content reader to
   2873  *        be queried multiple times for the same data;
   2874  *        however, if a `struct MHD_Response` is not re-used,
   2875  *        libmicrohttpd guarantees that "pos" will be
   2876  *        the sum of all non-negative return values
   2877  *        obtained from the content reader so far.
   2878  * @param buf where to copy the data
   2879  * @param max maximum number of bytes to copy to @a buf (size of @a buf)
   2880  * @return number of bytes written to @a buf;
   2881  *  0 is legal unless MHD is started in "internal" sockets polling mode
   2882  *    (since this would cause busy-waiting); 0 in "external" sockets
   2883  *    polling mode will cause this function to be called again once
   2884  *    any MHD_run*() function is called;
   2885  *  #MHD_CONTENT_READER_END_OF_STREAM (-1) for the regular
   2886  *    end of transmission (with chunked encoding, MHD will then
   2887  *    terminate the chunk and send any HTTP footers that might be
   2888  *    present; without chunked encoding and given an unknown
   2889  *    response size, MHD will simply close the connection; note
   2890  *    that while returning #MHD_CONTENT_READER_END_OF_STREAM is not technically
   2891  *    legal if a response size was specified, MHD accepts this
   2892  *    and treats it just as #MHD_CONTENT_READER_END_WITH_ERROR;
   2893  *  #MHD_CONTENT_READER_END_WITH_ERROR (-2) to indicate a server
   2894  *    error generating the response; this will cause MHD to simply
   2895  *    close the connection immediately.  If a response size was
   2896  *    given or if chunked encoding is in use, this will indicate
   2897  *    an error to the client.  Note, however, that if the client
   2898  *    does not know a response size and chunked encoding is not in
   2899  *    use, then clients will not be able to tell the difference between
   2900  *    #MHD_CONTENT_READER_END_WITH_ERROR and #MHD_CONTENT_READER_END_OF_STREAM.
   2901  *    This is not a limitation of MHD but rather of the HTTP protocol.
   2902  */
   2903 typedef ssize_t
   2904 (*MHD_ContentReaderCallback) (void *cls,
   2905                               uint64_t pos,
   2906                               char *buf,
   2907                               size_t max);
   2908 
   2909 
   2910 /**
   2911  * This method is called by libmicrohttpd if we
   2912  * are done with a content reader.  It should
   2913  * be used to free resources associated with the
   2914  * content reader.
   2915  *
   2916  * @param cls closure
   2917  * @ingroup response
   2918  */
   2919 typedef void
   2920 (*MHD_ContentReaderFreeCallback) (void *cls);
   2921 
   2922 
   2923 /**
   2924  * Iterator over key-value pairs where the value
   2925  * may be made available in increments and/or may
   2926  * not be zero-terminated.  Used for processing
   2927  * POST data.
   2928  *
   2929  * @param cls user-specified closure
   2930  * @param kind type of the value, always #MHD_POSTDATA_KIND when called from MHD
   2931  * @param key 0-terminated key for the value, NULL if not known. This value
   2932  *            is never NULL for url-encoded POST data.
   2933  * @param filename name of the uploaded file, NULL if not known
   2934  * @param content_type mime-type of the data, NULL if not known
   2935  * @param transfer_encoding encoding of the data, NULL if not known
   2936  * @param data pointer to @a size bytes of data at the
   2937  *              specified offset
   2938  * @param off offset of data in the overall value
   2939  * @param size number of bytes in @a data available
   2940  * @return #MHD_YES to continue iterating,
   2941  *         #MHD_NO to abort the iteration
   2942  */
   2943 typedef enum MHD_Result
   2944 (*MHD_PostDataIterator)(void *cls,
   2945                         enum MHD_ValueKind kind,
   2946                         const char *key,
   2947                         const char *filename,
   2948                         const char *content_type,
   2949                         const char *transfer_encoding,
   2950                         const char *data,
   2951                         uint64_t off,
   2952                         size_t size);
   2953 
   2954 /* **************** Daemon handling functions ***************** */
   2955 
   2956 /**
   2957  * Start a webserver on the given port.
   2958  *
   2959  * @param flags combination of `enum MHD_FLAG` values
   2960  * @param port port to bind to (in host byte order),
   2961  *        use '0' to bind to random free port,
   2962  *        ignored if MHD_OPTION_SOCK_ADDR or
   2963  *        MHD_OPTION_LISTEN_SOCKET is provided
   2964  *        or MHD_USE_NO_LISTEN_SOCKET is specified
   2965  * @param apc callback to call to check which clients
   2966  *        will be allowed to connect; you can pass NULL
   2967  *        in which case connections from any IP will be
   2968  *        accepted
   2969  * @param apc_cls extra argument to apc
   2970  * @param dh handler called for all requests (repeatedly)
   2971  * @param dh_cls extra argument to @a dh
   2972  * @param ap list of options (type-value pairs,
   2973  *        terminated with #MHD_OPTION_END).
   2974  * @return NULL on error, handle to daemon on success
   2975  * @ingroup event
   2976  */
   2977 _MHD_EXTERN struct MHD_Daemon *
   2978 MHD_start_daemon_va (unsigned int flags,
   2979                      uint16_t port,
   2980                      MHD_AcceptPolicyCallback apc, void *apc_cls,
   2981                      MHD_AccessHandlerCallback dh, void *dh_cls,
   2982                      va_list ap);
   2983 
   2984 
   2985 /**
   2986  * Start a webserver on the given port.  Variadic version of
   2987  * #MHD_start_daemon_va.
   2988  *
   2989  * @param flags combination of `enum MHD_FLAG` values
   2990  * @param port port to bind to (in host byte order),
   2991  *        use '0' to bind to random free port,
   2992  *        ignored if MHD_OPTION_SOCK_ADDR or
   2993  *        MHD_OPTION_LISTEN_SOCKET is provided
   2994  *        or MHD_USE_NO_LISTEN_SOCKET is specified
   2995  * @param apc callback to call to check which clients
   2996  *        will be allowed to connect; you can pass NULL
   2997  *        in which case connections from any IP will be
   2998  *        accepted
   2999  * @param apc_cls extra argument to apc
   3000  * @param dh handler called for all requests (repeatedly)
   3001  * @param dh_cls extra argument to @a dh
   3002  * @return NULL on error, handle to daemon on success
   3003  * @ingroup event
   3004  */
   3005 _MHD_EXTERN struct MHD_Daemon *
   3006 MHD_start_daemon (unsigned int flags,
   3007                   uint16_t port,
   3008                   MHD_AcceptPolicyCallback apc, void *apc_cls,
   3009                   MHD_AccessHandlerCallback dh, void *dh_cls,
   3010                   ...);
   3011 
   3012 
   3013 /**
   3014  * Stop accepting connections from the listening socket.  Allows
   3015  * clients to continue processing, but stops accepting new
   3016  * connections.  Note that the caller is responsible for closing the
   3017  * returned socket; however, if MHD is run using threads (anything but
   3018  * "external" sockets polling mode), it must not be closed until AFTER
   3019  * #MHD_stop_daemon has been called (as it is theoretically possible
   3020  * that an existing thread is still using it).
   3021  *
   3022  * Note that some thread modes require the caller to have passed
   3023  * #MHD_USE_ITC when using this API.  If this daemon is
   3024  * in one of those modes and this option was not given to
   3025  * #MHD_start_daemon, this function will return #MHD_INVALID_SOCKET.
   3026  *
   3027  * @param daemon daemon to stop accepting new connections for
   3028  * @return old listen socket on success, #MHD_INVALID_SOCKET if
   3029  *         the daemon was already not listening anymore
   3030  * @ingroup specialized
   3031  */
   3032 _MHD_EXTERN MHD_socket
   3033 MHD_quiesce_daemon (struct MHD_Daemon *daemon);
   3034 
   3035 
   3036 /**
   3037  * Shutdown an HTTP daemon.
   3038  *
   3039  * @param daemon daemon to stop
   3040  * @ingroup event
   3041  */
   3042 _MHD_EXTERN void
   3043 MHD_stop_daemon (struct MHD_Daemon *daemon);
   3044 
   3045 
   3046 /**
   3047  * Add another client connection to the set of connections managed by
   3048  * MHD.  This API is usually not needed (since MHD will accept inbound
   3049  * connections on the server socket).  Use this API in special cases,
   3050  * for example if your HTTP server is behind NAT and needs to connect
   3051  * out to the HTTP client, or if you are building a proxy.
   3052  *
   3053  * If you use this API in conjunction with an "internal" socket polling,
   3054  * you must set the option #MHD_USE_ITC to ensure that the freshly added
   3055  * connection is immediately processed by MHD.
   3056  *
   3057  * The given client socket will be managed (and closed!) by MHD after
   3058  * this call and must no longer be used directly by the application
   3059  * afterwards.
   3060  *
   3061  * @param daemon daemon that manages the connection
   3062  * @param client_socket socket to manage (MHD will expect
   3063  *        to receive an HTTP request from this socket next).
   3064  * @param addr IP address of the client
   3065  * @param addrlen number of bytes in @a addr
   3066  * @return #MHD_YES on success, #MHD_NO if this daemon could
   3067  *        not handle the connection (i.e. `malloc()` failed, etc).
   3068  *        The socket will be closed in any case; `errno` is
   3069  *        set to indicate further details about the error.
   3070  * @ingroup specialized
   3071  */
   3072 _MHD_EXTERN enum MHD_Result
   3073 MHD_add_connection (struct MHD_Daemon *daemon,
   3074                     MHD_socket client_socket,
   3075                     const struct sockaddr *addr,
   3076                     socklen_t addrlen);
   3077 
   3078 
   3079 /**
   3080  * Obtain the `select()` sets for this daemon.
   3081  * Daemon's FDs will be added to fd_sets. To get only
   3082  * daemon FDs in fd_sets, call FD_ZERO for each fd_set
   3083  * before calling this function. FD_SETSIZE is assumed
   3084  * to be platform's default.
   3085  *
   3086  * This function should be called only when MHD is configured to
   3087  * use "external" sockets polling with 'select()' or with 'epoll'.
   3088  * In the latter case, it will only add the single 'epoll' file
   3089  * descriptor used by MHD to the sets.
   3090  * It's necessary to use #MHD_get_timeout() to get maximum timeout
   3091  * value for `select()`. Usage of `select()` with indefinite timeout
   3092  * (or timeout larger than returned by #MHD_get_timeout()) will
   3093  * violate MHD API and may results in pending unprocessed data.
   3094  *
   3095  * This function must be called only for daemon started
   3096  * without #MHD_USE_INTERNAL_POLLING_THREAD flag.
   3097  *
   3098  * @param daemon daemon to get sets from
   3099  * @param read_fd_set read set
   3100  * @param write_fd_set write set
   3101  * @param except_fd_set except set
   3102  * @param max_fd increased to largest FD added (if larger
   3103  *               than existing value); can be NULL
   3104  * @return #MHD_YES on success, #MHD_NO if this
   3105  *         daemon was not started with the right
   3106  *         options for this call or any FD didn't
   3107  *         fit fd_set.
   3108  * @ingroup event
   3109  */
   3110 _MHD_EXTERN enum MHD_Result
   3111 MHD_get_fdset (struct MHD_Daemon *daemon,
   3112                fd_set *read_fd_set,
   3113                fd_set *write_fd_set,
   3114                fd_set *except_fd_set,
   3115                MHD_socket *max_fd);
   3116 
   3117 
   3118 /**
   3119  * Obtain the `select()` sets for this daemon.
   3120  * Daemon's FDs will be added to fd_sets. To get only
   3121  * daemon FDs in fd_sets, call FD_ZERO for each fd_set
   3122  * before calling this function.
   3123  *
   3124  * Passing custom FD_SETSIZE as @a fd_setsize allow usage of
   3125  * larger/smaller than platform's default fd_sets.
   3126  *
   3127  * This function should be called only when MHD is configured to
   3128  * use "external" sockets polling with 'select()' or with 'epoll'.
   3129  * In the latter case, it will only add the single 'epoll' file
   3130  * descriptor used by MHD to the sets.
   3131  * It's necessary to use #MHD_get_timeout() to get maximum timeout
   3132  * value for `select()`. Usage of `select()` with indefinite timeout
   3133  * (or timeout larger than returned by #MHD_get_timeout()) will
   3134  * violate MHD API and may results in pending unprocessed data.
   3135  *
   3136  * This function must be called only for daemon started
   3137  * without #MHD_USE_INTERNAL_POLLING_THREAD flag.
   3138  *
   3139  * @param daemon daemon to get sets from
   3140  * @param read_fd_set read set
   3141  * @param write_fd_set write set
   3142  * @param except_fd_set except set
   3143  * @param max_fd increased to largest FD added (if larger
   3144  *               than existing value); can be NULL
   3145  * @param fd_setsize value of FD_SETSIZE
   3146  * @return #MHD_YES on success, #MHD_NO if this
   3147  *         daemon was not started with the right
   3148  *         options for this call or any FD didn't
   3149  *         fit fd_set.
   3150  * @ingroup event
   3151  */
   3152 _MHD_EXTERN enum MHD_Result
   3153 MHD_get_fdset2 (struct MHD_Daemon *daemon,
   3154                 fd_set *read_fd_set,
   3155                 fd_set *write_fd_set,
   3156                 fd_set *except_fd_set,
   3157                 MHD_socket *max_fd,
   3158                 unsigned int fd_setsize);
   3159 
   3160 
   3161 /**
   3162  * Obtain the `select()` sets for this daemon.
   3163  * Daemon's FDs will be added to fd_sets. To get only
   3164  * daemon FDs in fd_sets, call FD_ZERO for each fd_set
   3165  * before calling this function. Size of fd_set is
   3166  * determined by current value of FD_SETSIZE.
   3167  *
   3168  * This function should be called only when MHD is configured to
   3169  * use "external" sockets polling with 'select()' or with 'epoll'.
   3170  * In the latter case, it will only add the single 'epoll' file
   3171  * descriptor used by MHD to the sets.
   3172  * It's necessary to use #MHD_get_timeout() to get maximum timeout
   3173  * value for `select()`. Usage of `select()` with indefinite timeout
   3174  * (or timeout larger than returned by #MHD_get_timeout()) will
   3175  * violate MHD API and may results in pending unprocessed data.
   3176  *
   3177  * This function must be called only for daemon started
   3178  * without #MHD_USE_INTERNAL_POLLING_THREAD flag.
   3179  *
   3180  * @param daemon daemon to get sets from
   3181  * @param read_fd_set read set
   3182  * @param write_fd_set write set
   3183  * @param except_fd_set except set
   3184  * @param max_fd increased to largest FD added (if larger
   3185  *               than existing value); can be NULL
   3186  * @return #MHD_YES on success, #MHD_NO if this
   3187  *         daemon was not started with the right
   3188  *         options for this call or any FD didn't
   3189  *         fit fd_set.
   3190  * @ingroup event
   3191  */
   3192 #define MHD_get_fdset(daemon,read_fd_set,write_fd_set,except_fd_set,max_fd) \
   3193         MHD_get_fdset2 ((daemon),(read_fd_set),(write_fd_set),(except_fd_set), \
   3194                         (max_fd),FD_SETSIZE)
   3195 
   3196 
   3197 /**
   3198  * Obtain timeout value for polling function for this daemon.
   3199  *
   3200  * This function set value to the amount of milliseconds for which polling
   3201  * function (`select()`, `poll()` or epoll) should at most block, not the
   3202  * timeout value set for connections.
   3203  *
   3204  * Any "external" sockets polling function must be called with the timeout
   3205  * value provided by this function. Smaller timeout values can be used for
   3206  * polling function if it is required for any reason, but using larger
   3207  * timeout value or no timeout (indefinite timeout) when this function
   3208  * return #MHD_YES will break MHD processing logic and result in "hung"
   3209  * connections with data pending in network buffers and other problems.
   3210  *
   3211  * It is important to always use this function (or #MHD_get_timeout64(),
   3212  * #MHD_get_timeout64s(), #MHD_get_timeout_i() functions) when "external"
   3213  * polling is used.
   3214  * If this function returns #MHD_YES then #MHD_run() (or #MHD_run_from_select())
   3215  * must be called right after return from polling function, regardless of
   3216  * the states of MHD FDs.
   3217  *
   3218  * In practice, if #MHD_YES is returned then #MHD_run() (or
   3219  * #MHD_run_from_select()) must be called not later than @a timeout
   3220  * millisecond even if no activity is detected on sockets by sockets
   3221  * polling function.
   3222  *
   3223  * @param daemon daemon to query for timeout
   3224  * @param[out] timeout set to the timeout (in milliseconds)
   3225  * @return #MHD_YES on success, #MHD_NO if timeouts are
   3226  *         not used and no data processing is pending.
   3227  * @ingroup event
   3228  */
   3229 _MHD_EXTERN enum MHD_Result
   3230 MHD_get_timeout (struct MHD_Daemon *daemon,
   3231                  MHD_UNSIGNED_LONG_LONG *timeout);
   3232 
   3233 
   3234 /**
   3235  * Free the memory allocated by MHD.
   3236  *
   3237  * If any MHD function explicitly mentions that returned pointer must be
   3238  * freed by this function, then no other method must be used to free
   3239  * the memory.
   3240  *
   3241  * @param ptr the pointer to free.
   3242  * @sa #MHD_digest_auth_get_username(), #MHD_basic_auth_get_username_password3()
   3243  * @sa #MHD_basic_auth_get_username_password()
   3244  * @note Available since #MHD_VERSION 0x00095600
   3245  * @ingroup specialized
   3246  */
   3247 _MHD_EXTERN void
   3248 MHD_free (void *ptr);
   3249 
   3250 /**
   3251  * Obtain timeout value for external polling function for this daemon.
   3252  *
   3253  * This function set value to the amount of milliseconds for which polling
   3254  * function (`select()`, `poll()` or epoll) should at most block, not the
   3255  * timeout value set for connections.
   3256  *
   3257  * Any "external" sockets polling function must be called with the timeout
   3258  * value provided by this function. Smaller timeout values can be used for
   3259  * polling function if it is required for any reason, but using larger
   3260  * timeout value or no timeout (indefinite timeout) when this function
   3261  * return #MHD_YES will break MHD processing logic and result in "hung"
   3262  * connections with data pending in network buffers and other problems.
   3263  *
   3264  * It is important to always use this function (or #MHD_get_timeout(),
   3265  * #MHD_get_timeout64s(), #MHD_get_timeout_i() functions) when "external"
   3266  * polling is used.
   3267  * If this function returns #MHD_YES then #MHD_run() (or #MHD_run_from_select())
   3268  * must be called right after return from polling function, regardless of
   3269  * the states of MHD FDs.
   3270  *
   3271  * In practice, if #MHD_YES is returned then #MHD_run() (or
   3272  * #MHD_run_from_select()) must be called not later than @a timeout
   3273  * millisecond even if no activity is detected on sockets by sockets
   3274  * polling function.
   3275  *
   3276  * @param daemon daemon to query for timeout
   3277  * @param[out] timeout64 the pointer to the variable to be set to the
   3278  *                  timeout (in milliseconds)
   3279  * @return #MHD_YES if timeout value has been set,
   3280  *         #MHD_NO if timeouts are not used and no data processing is pending.
   3281  * @note Available since #MHD_VERSION 0x00097701
   3282  * @ingroup event
   3283  */
   3284 _MHD_EXTERN enum MHD_Result
   3285 MHD_get_timeout64 (struct MHD_Daemon *daemon,
   3286                    uint64_t *timeout);
   3287 
   3288 
   3289 /**
   3290  * Obtain timeout value for external polling function for this daemon.
   3291  *
   3292  * This function set value to the amount of milliseconds for which polling
   3293  * function (`select()`, `poll()` or epoll) should at most block, not the
   3294  * timeout value set for connections.
   3295  *
   3296  * Any "external" sockets polling function must be called with the timeout
   3297  * value provided by this function (if returned value is non-negative).
   3298  * Smaller timeout values can be used for polling function if it is required
   3299  * for any reason, but using larger timeout value or no timeout (indefinite
   3300  * timeout) when this function returns non-negative value will break MHD
   3301  * processing logic and result in "hung" connections with data pending in
   3302  * network buffers and other problems.
   3303  *
   3304  * It is important to always use this function (or #MHD_get_timeout(),
   3305  * #MHD_get_timeout64(), #MHD_get_timeout_i() functions) when "external"
   3306  * polling is used.
   3307  * If this function returns non-negative value then #MHD_run() (or
   3308  * #MHD_run_from_select()) must be called right after return from polling
   3309  * function, regardless of the states of MHD FDs.
   3310  *
   3311  * In practice, if zero or positive value is returned then #MHD_run() (or
   3312  * #MHD_run_from_select()) must be called not later than returned amount of
   3313  * millisecond even if no activity is detected on sockets by sockets
   3314  * polling function.
   3315  *
   3316  * @param daemon the daemon to query for timeout
   3317  * @return -1 if connections' timeouts are not set and no data processing
   3318  *         is pending, so external polling function may wait for sockets
   3319  *         activity for indefinite amount of time,
   3320  *         otherwise returned value is the the maximum amount of millisecond
   3321  *         that external polling function must wait for the activity of FDs.
   3322  * @note Available since #MHD_VERSION 0x00097701
   3323  * @ingroup event
   3324  */
   3325 _MHD_EXTERN int64_t
   3326 MHD_get_timeout64s (struct MHD_Daemon *daemon);
   3327 
   3328 
   3329 /**
   3330  * Obtain timeout value for external polling function for this daemon.
   3331  *
   3332  * This function set value to the amount of milliseconds for which polling
   3333  * function (`select()`, `poll()` or epoll) should at most block, not the
   3334  * timeout value set for connections.
   3335  *
   3336  * Any "external" sockets polling function must be called with the timeout
   3337  * value provided by this function (if returned value is non-negative).
   3338  * Smaller timeout values can be used for polling function if it is required
   3339  * for any reason, but using larger timeout value or no timeout (indefinite
   3340  * timeout) when this function returns non-negative value will break MHD
   3341  * processing logic and result in "hung" connections with data pending in
   3342  * network buffers and other problems.
   3343  *
   3344  * It is important to always use this function (or #MHD_get_timeout(),
   3345  * #MHD_get_timeout64(), #MHD_get_timeout64s() functions) when "external"
   3346  * polling is used.
   3347  * If this function returns non-negative value then #MHD_run() (or
   3348  * #MHD_run_from_select()) must be called right after return from polling
   3349  * function, regardless of the states of MHD FDs.
   3350  *
   3351  * In practice, if zero or positive value is returned then #MHD_run() (or
   3352  * #MHD_run_from_select()) must be called not later than returned amount of
   3353  * millisecond even if no activity is detected on sockets by sockets
   3354  * polling function.
   3355  *
   3356  * @param daemon the daemon to query for timeout
   3357  * @return -1 if connections' timeouts are not set and no data processing
   3358  *         is pending, so external polling function may wait for sockets
   3359  *         activity for indefinite amount of time,
   3360  *         otherwise returned value is the the maximum amount of millisecond
   3361  *         (capped at INT_MAX) that external polling function must wait
   3362  *         for the activity of FDs.
   3363  * @note Available since #MHD_VERSION 0x00097701
   3364  * @ingroup event
   3365  */
   3366 _MHD_EXTERN int
   3367 MHD_get_timeout_i (struct MHD_Daemon *daemon);
   3368 
   3369 
   3370 /**
   3371  * Run webserver operations (without blocking unless in client callbacks).
   3372  *
   3373  * This method should be called by clients in combination with
   3374  * #MHD_get_fdset() (or #MHD_get_daemon_info() with MHD_DAEMON_INFO_EPOLL_FD
   3375  * if epoll is used) and #MHD_get_timeout() if the client-controlled
   3376  * connection polling method is used (i.e. daemon was started without
   3377  * #MHD_USE_INTERNAL_POLLING_THREAD flag).
   3378  *
   3379  * This function is a convenience method, which is useful if the
   3380  * fd_sets from #MHD_get_fdset were not directly passed to `select()`;
   3381  * with this function, MHD will internally do the appropriate `select()`
   3382  * call itself again.  While it is acceptable to call #MHD_run (if
   3383  * #MHD_USE_INTERNAL_POLLING_THREAD is not set) at any moment, you should
   3384  * call #MHD_run_from_select() if performance is important (as it saves an
   3385  * expensive call to `select()`).
   3386  *
   3387  * If #MHD_get_timeout() returned #MHD_YES, than this function must be called
   3388  * right after polling function returns regardless of detected activity on
   3389  * the daemon's FDs.
   3390  *
   3391  * @param daemon daemon to run
   3392  * @return #MHD_YES on success, #MHD_NO if this
   3393  *         daemon was not started with the right
   3394  *         options for this call.
   3395  * @ingroup event
   3396  */
   3397 _MHD_EXTERN enum MHD_Result
   3398 MHD_run (struct MHD_Daemon *daemon);
   3399 
   3400 
   3401 /**
   3402  * Run websever operation with possible blocking.
   3403  *
   3404  * This function does the following: waits for any network event not more than
   3405  * specified number of milliseconds, processes all incoming and outgoing data,
   3406  * processes new connections, processes any timed-out connection, and does
   3407  * other things required to run webserver.
   3408  * Once all connections are processed, function returns.
   3409  *
   3410  * This function is useful for quick and simple (lazy) webserver implementation
   3411  * if application needs to run a single thread only and does not have any other
   3412  * network activity.
   3413  *
   3414  * This function calls MHD_get_timeout() internally and use returned value as
   3415  * maximum wait time if it less than value of @a millisec parameter.
   3416  *
   3417  * It is expected that the "external" socket polling function is not used in
   3418  * conjunction with this function unless the @a millisec is set to zero.
   3419  *
   3420  * @param daemon the daemon to run
   3421  * @param millisec the maximum time in milliseconds to wait for network and
   3422  *                 other events. Note: there is no guarantee that function
   3423  *                 blocks for the specified amount of time. The real processing
   3424  *                 time can be shorter (if some data or connection timeout
   3425  *                 comes earlier) or longer (if data processing requires more
   3426  *                 time, especially in user callbacks).
   3427  *                 If set to '0' then function does not block and processes
   3428  *                 only already available data (if any).
   3429  *                 If set to '-1' then function waits for events
   3430  *                 indefinitely (blocks until next network activity or
   3431  *                 connection timeout).
   3432  * @return #MHD_YES on success, #MHD_NO if this
   3433  *         daemon was not started with the right
   3434  *         options for this call or some serious
   3435  *         unrecoverable error occurs.
   3436  * @note Available since #MHD_VERSION 0x00097206
   3437  * @ingroup event
   3438  */
   3439 _MHD_EXTERN enum MHD_Result
   3440 MHD_run_wait (struct MHD_Daemon *daemon,
   3441               int32_t millisec);
   3442 
   3443 
   3444 /**
   3445  * Run webserver operations. This method should be called by clients
   3446  * in combination with #MHD_get_fdset and #MHD_get_timeout() if the
   3447  * client-controlled select method is used.
   3448  *
   3449  * You can use this function instead of #MHD_run if you called
   3450  * `select()` on the result from #MHD_get_fdset.  File descriptors in
   3451  * the sets that are not controlled by MHD will be ignored.  Calling
   3452  * this function instead of #MHD_run is more efficient as MHD will
   3453  * not have to call `select()` again to determine which operations are
   3454  * ready.
   3455  *
   3456  * If #MHD_get_timeout() returned #MHD_YES, than this function must be
   3457  * called right after `select()` returns regardless of detected activity
   3458  * on the daemon's FDs.
   3459  *
   3460  * This function cannot be used with daemon started with
   3461  * #MHD_USE_INTERNAL_POLLING_THREAD flag.
   3462  *
   3463  * @param daemon daemon to run select loop for
   3464  * @param read_fd_set read set
   3465  * @param write_fd_set write set
   3466  * @param except_fd_set except set
   3467  * @return #MHD_NO on serious errors, #MHD_YES on success
   3468  * @ingroup event
   3469  */
   3470 _MHD_EXTERN enum MHD_Result
   3471 MHD_run_from_select (struct MHD_Daemon *daemon,
   3472                      const fd_set *read_fd_set,
   3473                      const fd_set *write_fd_set,
   3474                      const fd_set *except_fd_set);
   3475 
   3476 
   3477 /**
   3478  * Run webserver operations. This method should be called by clients
   3479  * in combination with #MHD_get_fdset and #MHD_get_timeout() if the
   3480  * client-controlled select method is used.
   3481  * This function specifies FD_SETSIZE used when provided fd_sets were
   3482  * created. It is important on platforms where FD_SETSIZE can be
   3483  * overridden.
   3484  *
   3485  * You can use this function instead of #MHD_run if you called
   3486  * 'select()' on the result from #MHD_get_fdset2().  File descriptors in
   3487  * the sets that are not controlled by MHD will be ignored.  Calling
   3488  * this function instead of #MHD_run() is more efficient as MHD will
   3489  * not have to call 'select()' again to determine which operations are
   3490  * ready.
   3491  *
   3492  * If #MHD_get_timeout() returned #MHD_YES, than this function must be
   3493  * called right after 'select()' returns regardless of detected activity
   3494  * on the daemon's FDs.
   3495  *
   3496  * This function cannot be used with daemon started with
   3497  * #MHD_USE_INTERNAL_POLLING_THREAD flag.
   3498  *
   3499  * @param daemon the daemon to run select loop for
   3500  * @param read_fd_set the read set
   3501  * @param write_fd_set the write set
   3502  * @param except_fd_set the except set
   3503  * @param fd_setsize the value of FD_SETSIZE
   3504  * @return #MHD_NO on serious errors, #MHD_YES on success
   3505  * @sa #MHD_get_fdset2(), #MHD_OPTION_APP_FD_SETSIZE
   3506  * @ingroup event
   3507  */
   3508 _MHD_EXTERN enum MHD_Result
   3509 MHD_run_from_select2 (struct MHD_Daemon *daemon,
   3510                       const fd_set *read_fd_set,
   3511                       const fd_set *write_fd_set,
   3512                       const fd_set *except_fd_set,
   3513                       unsigned int fd_setsize);
   3514 
   3515 
   3516 /**
   3517  * Run webserver operations. This method should be called by clients
   3518  * in combination with #MHD_get_fdset and #MHD_get_timeout() if the
   3519  * client-controlled select method is used.
   3520  * This macro automatically substitutes current FD_SETSIZE value.
   3521  * It is important on platforms where FD_SETSIZE can be overridden.
   3522  *
   3523  * You can use this function instead of #MHD_run if you called
   3524  * 'select()' on the result from #MHD_get_fdset2().  File descriptors in
   3525  * the sets that are not controlled by MHD will be ignored.  Calling
   3526  * this function instead of #MHD_run() is more efficient as MHD will
   3527  * not have to call 'select()' again to determine which operations are
   3528  * ready.
   3529  *
   3530  * If #MHD_get_timeout() returned #MHD_YES, than this function must be
   3531  * called right after 'select()' returns regardless of detected activity
   3532  * on the daemon's FDs.
   3533  *
   3534  * This function cannot be used with daemon started with
   3535  * #MHD_USE_INTERNAL_POLLING_THREAD flag.
   3536  *
   3537  * @param daemon the daemon to run select loop for
   3538  * @param read_fd_set the read set
   3539  * @param write_fd_set the write set
   3540  * @param except_fd_set the except set
   3541  * @param fd_setsize the value of FD_SETSIZE
   3542  * @return #MHD_NO on serious errors, #MHD_YES on success
   3543  * @sa #MHD_get_fdset2(), #MHD_OPTION_APP_FD_SETSIZE
   3544  * @ingroup event
   3545  */
   3546 #define MHD_run_from_select(d,r,w,e) \
   3547         MHD_run_from_select2 ((d),(r),(w),(e),(unsigned int) (FD_SETSIZE))
   3548 
   3549 /* **************** Connection handling functions ***************** */
   3550 
   3551 
   3552 /**
   3553  * Get request URI path (the request target without query part).
   3554  *
   3555  * The value obtained by this function is the same value as @a url provided
   3556  * for #MHD_AccessHandlerCallback callback, but this function also provides
   3557  * the size of the string.
   3558  *
   3559  * This function is critically important when binary zero is allowed by daemon
   3560  * option #MHD_OPTION_ALLOW_BIN_ZERO_IN_URI_PATH as this is the only way to
   3561  * get the non-truncated request URI.
   3562  *
   3563  * Returned @a uri pointer is valid until response is started or connection
   3564  * is terminated.
   3565  *
   3566  * @param connection the connection to URI from
   3567  * @param[out] uri set to the request URI without query part, may contain
   3568  *                 binary zeros (NUL) characters, never set to NULL on
   3569  *                 success; can be NULL
   3570  * @param[out] uri_size set to the size of the @a uri in bytes, not including
   3571  *                       final zero-termination; can be NULL
   3572  * @return #MHD_NO if failed (request is not yet processed or response has
   3573  *                 been queued already);
   3574  *         #MHD_YES on success (*uri set to valid pointer)
   3575  * @note Available since #MHD_VERSION 0x01000201
   3576  * @sa #MHD_OPTION_ALLOW_BIN_ZERO_IN_URI_PATH, #MHD_AccessHandlerCallback
   3577  * @ingroup request
   3578  */
   3579 _MHD_EXTERN enum MHD_Result
   3580 MHD_get_connection_URI_path_n (struct MHD_Connection *connection,
   3581                                const char **uri,
   3582                                size_t *uri_size);
   3583 
   3584 /**
   3585  * Get all of the headers from the request.
   3586  *
   3587  * @param connection connection to get values from
   3588  * @param kind types of values to iterate over, can be a bitmask
   3589  * @param iterator callback to call on each header;
   3590  *        may be NULL (then just count headers)
   3591  * @param iterator_cls extra argument to @a iterator
   3592  * @return number of entries iterated over,
   3593  *         -1 if connection is NULL.
   3594  * @ingroup request
   3595  */
   3596 _MHD_EXTERN int
   3597 MHD_get_connection_values (struct MHD_Connection *connection,
   3598                            enum MHD_ValueKind kind,
   3599                            MHD_KeyValueIterator iterator,
   3600                            void *iterator_cls);
   3601 
   3602 
   3603 /**
   3604  * Get all of the headers from the request.
   3605  *
   3606  * @param connection connection to get values from
   3607  * @param kind types of values to iterate over, can be a bitmask
   3608  * @param iterator callback to call on each header;
   3609  *        may be NULL (then just count headers)
   3610  * @param iterator_cls extra argument to @a iterator
   3611  * @return number of entries iterated over,
   3612  *         -1 if connection is NULL.
   3613  * @note Available since #MHD_VERSION 0x00096400
   3614  * @ingroup request
   3615  */
   3616 _MHD_EXTERN int
   3617 MHD_get_connection_values_n (struct MHD_Connection *connection,
   3618                              enum MHD_ValueKind kind,
   3619                              MHD_KeyValueIteratorN iterator,
   3620                              void *iterator_cls);
   3621 
   3622 
   3623 /**
   3624  * This function can be used to add an entry to the HTTP headers of a
   3625  * connection (so that the #MHD_get_connection_values function will
   3626  * return them -- and the `struct MHD_PostProcessor` will also see
   3627  * them).  This maybe required in certain situations (see Mantis
   3628  * #1399) where (broken) HTTP implementations fail to supply values
   3629  * needed by the post processor (or other parts of the application).
   3630  *
   3631  * This function MUST only be called from within the
   3632  * #MHD_AccessHandlerCallback (otherwise, access maybe improperly
   3633  * synchronized).  Furthermore, the client must guarantee that the key
   3634  * and value arguments are 0-terminated strings that are NOT freed
   3635  * until the connection is closed.  (The easiest way to do this is by
   3636  * passing only arguments to permanently allocated strings.).
   3637  *
   3638  * @param connection the connection for which a
   3639  *  value should be set
   3640  * @param kind kind of the value
   3641  * @param key key for the value
   3642  * @param value the value itself
   3643  * @return #MHD_NO if the operation could not be
   3644  *         performed due to insufficient memory;
   3645  *         #MHD_YES on success
   3646  * @ingroup request
   3647  */
   3648 _MHD_EXTERN enum MHD_Result
   3649 MHD_set_connection_value (struct MHD_Connection *connection,
   3650                           enum MHD_ValueKind kind,
   3651                           const char *key,
   3652                           const char *value);
   3653 
   3654 
   3655 /**
   3656  * This function can be used to add an arbitrary entry to connection.
   3657  * This function could add entry with binary zero, which is allowed
   3658  * for #MHD_GET_ARGUMENT_KIND. For other kind on entries it is
   3659  * recommended to use #MHD_set_connection_value.
   3660  *
   3661  * This function MUST only be called from within the
   3662  * #MHD_AccessHandlerCallback (otherwise, access maybe improperly
   3663  * synchronized).  Furthermore, the client must guarantee that the key
   3664  * and value arguments are 0-terminated strings that are NOT freed
   3665  * until the connection is closed.  (The easiest way to do this is by
   3666  * passing only arguments to permanently allocated strings.).
   3667  *
   3668  * @param connection the connection for which a
   3669  *  value should be set
   3670  * @param kind kind of the value
   3671  * @param key key for the value, must be zero-terminated
   3672  * @param key_size number of bytes in @a key (excluding 0-terminator)
   3673  * @param value the value itself, must be zero-terminated
   3674  * @param value_size number of bytes in @a value (excluding 0-terminator)
   3675  * @return #MHD_NO if the operation could not be
   3676  *         performed due to insufficient memory;
   3677  *         #MHD_YES on success
   3678  * @note Available since #MHD_VERSION 0x00096400
   3679  * @ingroup request
   3680  */
   3681 _MHD_EXTERN enum MHD_Result
   3682 MHD_set_connection_value_n (struct MHD_Connection *connection,
   3683                             enum MHD_ValueKind kind,
   3684                             const char *key,
   3685                             size_t key_size,
   3686                             const char *value,
   3687                             size_t value_size);
   3688 
   3689 
   3690 /**
   3691  * Sets the global error handler to a different implementation.
   3692  *
   3693  * @a cb will only be called in the case of typically fatal, serious internal
   3694  * consistency issues or serious system failures like failed lock of mutex.
   3695  *
   3696  * These issues should only arise in the case of serious memory corruption or
   3697  * similar problems with the architecture, there is no safe way to continue
   3698  * even for closing of the application.
   3699  *
   3700  * The default implementation that is used if no panic function is set simply
   3701  * prints an error message and calls `abort()`.
   3702  * Alternative implementations might call `exit()` or other similar functions.
   3703  *
   3704  * @param cb new error handler or NULL to use default handler
   3705  * @param cls passed to @a cb
   3706  * @ingroup logging
   3707  */
   3708 _MHD_EXTERN void
   3709 MHD_set_panic_func (MHD_PanicCallback cb, void *cls);
   3710 
   3711 
   3712 /**
   3713  * Process escape sequences ('%HH') Updates val in place; the
   3714  * result cannot be larger than the input.
   3715  * The result is still be 0-terminated.
   3716  *
   3717  * @param val value to unescape (modified in the process)
   3718  * @return length of the resulting val (`strlen(val)` may be
   3719  *  shorter afterwards due to elimination of escape sequences)
   3720  */
   3721 _MHD_EXTERN size_t
   3722 MHD_http_unescape (char *val);
   3723 
   3724 
   3725 /**
   3726  * Get a particular header value.  If multiple
   3727  * values match the kind, return any one of them.
   3728  *
   3729  * @param connection connection to get values from
   3730  * @param kind what kind of value are we looking for
   3731  * @param key the header to look for, NULL to lookup 'trailing' value without a key
   3732  * @return NULL if no such item was found
   3733  * @ingroup request
   3734  */
   3735 _MHD_EXTERN const char *
   3736 MHD_lookup_connection_value (struct MHD_Connection *connection,
   3737                              enum MHD_ValueKind kind,
   3738                              const char *key);
   3739 
   3740 
   3741 /**
   3742  * Get a particular header value.  If multiple
   3743  * values match the kind, return any one of them.
   3744  * @note Since MHD_VERSION 0x00096304
   3745  *
   3746  * @param connection connection to get values from
   3747  * @param kind what kind of value are we looking for
   3748  * @param key the header to look for, NULL to lookup 'trailing' value without a key
   3749  * @param key_size the length of @a key in bytes
   3750  * @param[out] value_ptr the pointer to variable, which will be set to found value,
   3751  *                       will not be updated if key not found,
   3752  *                       could be NULL to just check for presence of @a key
   3753  * @param[out] value_size_ptr the pointer variable, which will set to found value,
   3754  *                            will not be updated if key not found,
   3755  *                            could be NULL
   3756  * @return #MHD_YES if key is found,
   3757  *         #MHD_NO otherwise.
   3758  * @ingroup request
   3759  */
   3760 _MHD_EXTERN enum MHD_Result
   3761 MHD_lookup_connection_value_n (struct MHD_Connection *connection,
   3762                                enum MHD_ValueKind kind,
   3763                                const char *key,
   3764                                size_t key_size,
   3765                                const char **value_ptr,
   3766                                size_t *value_size_ptr);
   3767 
   3768 
   3769 /**
   3770  * Queue a response to be transmitted to the client (as soon as
   3771  * possible but after #MHD_AccessHandlerCallback returns).
   3772  *
   3773  * For any active connection this function must be called
   3774  * only by #MHD_AccessHandlerCallback callback.
   3775  *
   3776  * For suspended connection this function can be called at any moment (this
   3777  * behaviour is deprecated and will be removed!). Response  will be sent
   3778  * as soon as connection is resumed.
   3779  *
   3780  * For single thread environment, when MHD is used in "external polling" mode
   3781  * (without MHD_USE_SELECT_INTERNALLY) this function can be called any
   3782  * time (this behaviour is deprecated and will be removed!).
   3783  *
   3784  * If HTTP specifications require use no body in reply, like @a status_code with
   3785  * value 1xx, the response body is automatically not sent even if it is present
   3786  * in the response. No "Content-Length" or "Transfer-Encoding" headers are
   3787  * generated and added.
   3788  *
   3789  * When the response is used to respond HEAD request or used with @a status_code
   3790  * #MHD_HTTP_NOT_MODIFIED, then response body is not sent, but "Content-Length"
   3791  * header is added automatically based the size of the body in the response.
   3792  * If body size it set to #MHD_SIZE_UNKNOWN or chunked encoding is enforced
   3793  * then "Transfer-Encoding: chunked" header (for HTTP/1.1 only) is added instead
   3794  * of "Content-Length" header. For example, if response with zero-size body is
   3795  * used for HEAD request, then "Content-Length: 0" is added automatically to
   3796  * reply headers.
   3797  * @sa #MHD_RF_HEAD_ONLY_RESPONSE
   3798  *
   3799  * In situations, where reply body is required, like answer for the GET request
   3800  * with @a status_code #MHD_HTTP_OK, headers "Content-Length" (for known body
   3801  * size) or "Transfer-Encoding: chunked" (for #MHD_SIZE_UNKNOWN with HTTP/1.1)
   3802  * are added automatically.
   3803  * In practice, the same response object can be used to respond to both HEAD and
   3804  * GET requests.
   3805  *
   3806  * @param connection the connection identifying the client
   3807  * @param status_code HTTP status code (i.e. #MHD_HTTP_OK)
   3808  * @param response response to transmit, the NULL is tolerated
   3809  * @return #MHD_NO on error (reply already sent, response is NULL),
   3810  *         #MHD_YES on success or if message has been queued
   3811  * @ingroup response
   3812  * @sa #MHD_AccessHandlerCallback
   3813  */
   3814 _MHD_EXTERN enum MHD_Result
   3815 MHD_queue_response (struct MHD_Connection *connection,
   3816                     unsigned int status_code,
   3817                     struct MHD_Response *response);
   3818 
   3819 
   3820 /**
   3821  * Suspend handling of network data for a given connection.
   3822  * This can be used to dequeue a connection from MHD's event loop
   3823  * (not applicable to thread-per-connection!) for a while.
   3824  *
   3825  * If you use this API in conjunction with an "internal" socket polling,
   3826  * you must set the option #MHD_USE_ITC to ensure that a resumed
   3827  * connection is immediately processed by MHD.
   3828  *
   3829  * Suspended connections continue to count against the total number of
   3830  * connections allowed (per daemon, as well as per IP, if such limits
   3831  * are set).  Suspended connections will NOT time out; timeouts will
   3832  * restart when the connection handling is resumed.  While a
   3833  * connection is suspended, MHD will not detect disconnects by the
   3834  * client.
   3835  *
   3836  * The only safe way to call this function is to call it from the
   3837  * #MHD_AccessHandlerCallback or #MHD_ContentReaderCallback.
   3838  *
   3839  * Finally, it is an API violation to call #MHD_stop_daemon while
   3840  * having suspended connections (this will at least create memory and
   3841  * socket leaks or lead to undefined behavior).  You must explicitly
   3842  * resume all connections before stopping the daemon.
   3843  *
   3844  * @param connection the connection to suspend
   3845  *
   3846  * @sa #MHD_AccessHandlerCallback
   3847  */
   3848 _MHD_EXTERN void
   3849 MHD_suspend_connection (struct MHD_Connection *connection);
   3850 
   3851 
   3852 /**
   3853  * Resume handling of network data for suspended connection.  It is
   3854  * safe to resume a suspended connection at any time.  Calling this
   3855  * function on a connection that was not previously suspended will
   3856  * result in undefined behavior.
   3857  *
   3858  * If you are using this function in "external" sockets polling mode, you must
   3859  * make sure to run #MHD_run() and #MHD_get_timeout() afterwards (before
   3860  * again calling #MHD_get_fdset()), as otherwise the change may not be
   3861  * reflected in the set returned by #MHD_get_fdset() and you may end up
   3862  * with a connection that is stuck until the next network activity.
   3863  *
   3864  * This function may be called from any thread.  In "external" sockets
   3865  * polling mode it writes to the inter-thread communication channel that
   3866  * #MHD_ALLOW_SUSPEND_RESUME sets up, and as #MHD_get_fdset() puts the
   3867  * reading end of that channel into the read set, a call from another
   3868  * thread interrupts a select()/poll() that the application is blocked
   3869  * in.  This matters because #MHD_get_timeout() reports no timeout at
   3870  * all while every connection is suspended, so the application would
   3871  * otherwise block indefinitely.  The channel is level triggered, hence
   3872  * a resume issued between #MHD_get_fdset() and select() cannot be lost.
   3873  *
   3874  * @param connection the connection to resume
   3875  */
   3876 _MHD_EXTERN void
   3877 MHD_resume_connection (struct MHD_Connection *connection);
   3878 
   3879 
   3880 /* **************** Response manipulation functions ***************** */
   3881 
   3882 
   3883 /**
   3884  * Flags for special handling of responses.
   3885  */
   3886 enum MHD_ResponseFlags
   3887 {
   3888   /**
   3889    * Default: no special flags.
   3890    * @note Available since #MHD_VERSION 0x00093701
   3891    */
   3892   MHD_RF_NONE = 0,
   3893 
   3894   /**
   3895    * Only respond in conservative (dumb) HTTP/1.0-compatible mode.
   3896    * Response still use HTTP/1.1 version in header, but always close
   3897    * the connection after sending the response and do not use chunked
   3898    * encoding for the response.
   3899    * You can also set the #MHD_RF_HTTP_1_0_SERVER flag to force
   3900    * HTTP/1.0 version in the response.
   3901    * Responses are still compatible with HTTP/1.1.
   3902    * This option can be used to communicate with some broken client, which
   3903    * does not implement HTTP/1.1 features, but advertises HTTP/1.1 support.
   3904    * @note Available since #MHD_VERSION 0x00097308
   3905    */
   3906   MHD_RF_HTTP_1_0_COMPATIBLE_STRICT = 1 << 0,
   3907   /**
   3908    * The same as #MHD_RF_HTTP_1_0_COMPATIBLE_STRICT
   3909    * @note Available since #MHD_VERSION 0x00093701
   3910    */
   3911   MHD_RF_HTTP_VERSION_1_0_ONLY = 1 << 0,
   3912 
   3913   /**
   3914    * Only respond in HTTP 1.0-mode.
   3915    * Contrary to the #MHD_RF_HTTP_1_0_COMPATIBLE_STRICT flag, the response's
   3916    * HTTP version will always be set to 1.0 and keep-alive connections
   3917    * will be used if explicitly requested by the client.
   3918    * The "Connection:" header will be added for both "close" and "keep-alive"
   3919    * connections.
   3920    * Chunked encoding will not be used for the response.
   3921    * Due to backward compatibility, responses still can be used with
   3922    * HTTP/1.1 clients.
   3923    * This option can be used to emulate HTTP/1.0 server (for response part
   3924    * only as chunked encoding in requests (if any) is processed by MHD).
   3925    * @note Available since #MHD_VERSION 0x00097308
   3926    */
   3927   MHD_RF_HTTP_1_0_SERVER = 1 << 1,
   3928   /**
   3929    * The same as #MHD_RF_HTTP_1_0_SERVER
   3930    * @note Available since #MHD_VERSION 0x00096000
   3931    */
   3932   MHD_RF_HTTP_VERSION_1_0_RESPONSE = 1 << 1,
   3933 
   3934   /**
   3935    * Disable sanity check preventing clients from manually
   3936    * setting the HTTP content length option.
   3937    * Allow to set several "Content-Length" headers. These headers will
   3938    * be used even with replies without body.
   3939    * @note Available since #MHD_VERSION 0x00096702
   3940    */
   3941   MHD_RF_INSANITY_HEADER_CONTENT_LENGTH = 1 << 2,
   3942 
   3943   /**
   3944    * Enable sending of "Connection: keep-alive" header even for
   3945    * HTTP/1.1 clients when "Keep-Alive" connection is used.
   3946    * Disabled by default for HTTP/1.1 clients as per RFC.
   3947    * @note Available since #MHD_VERSION 0x00097310
   3948    */
   3949   MHD_RF_SEND_KEEP_ALIVE_HEADER = 1 << 3,
   3950 
   3951   /**
   3952    * Enable special processing of the response as body-less (with undefined
   3953    * body size). No automatic "Content-Length" or "Transfer-Encoding: chunked"
   3954    * headers are added when the response is used with #MHD_HTTP_NOT_MODIFIED
   3955    * code or to respond to HEAD request.
   3956    * The flag also allow to set arbitrary "Content-Length" by
   3957    * MHD_add_response_header() function.
   3958    * This flag value can be used only with responses created without body
   3959    * (zero-size body).
   3960    * Responses with this flag enabled cannot be used in situations where
   3961    * reply body must be sent to the client.
   3962    * This flag is primarily intended to be used when automatic "Content-Length"
   3963    * header is undesirable in response to HEAD requests.
   3964    * @note Available since #MHD_VERSION 0x00097701
   3965    */
   3966   MHD_RF_HEAD_ONLY_RESPONSE = 1 << 4
   3967 } _MHD_FIXED_FLAGS_ENUM;
   3968 
   3969 
   3970 /**
   3971  * MHD options (for future extensions).
   3972  */
   3973 enum MHD_ResponseOptions
   3974 {
   3975   /**
   3976    * End of the list of options.
   3977    */
   3978   MHD_RO_END = 0
   3979 } _MHD_FIXED_ENUM;
   3980 
   3981 
   3982 /**
   3983  * Set special flags and options for a response.
   3984  *
   3985  * @param response the response to modify
   3986  * @param flags to set for the response
   3987  * @param ... #MHD_RO_END terminated list of options
   3988  * @return #MHD_YES on success, #MHD_NO on error
   3989  */
   3990 _MHD_EXTERN enum MHD_Result
   3991 MHD_set_response_options (struct MHD_Response *response,
   3992                           enum MHD_ResponseFlags flags,
   3993                           ...);
   3994 
   3995 
   3996 /**
   3997  * Create a response object.
   3998  * The response object can be extended with header information and then be used
   3999  * any number of times.
   4000  *
   4001  * If response object is used to answer HEAD request then the body of the
   4002  * response is not used, while all headers (including automatic headers) are
   4003  * used.
   4004  *
   4005  * @param size size of the data portion of the response, #MHD_SIZE_UNKNOWN for unknown
   4006  * @param block_size preferred block size for querying crc (advisory only,
   4007  *                   MHD may still call @a crc using smaller chunks); this
   4008  *                   is essentially the buffer size used for IO, clients
   4009  *                   should pick a value that is appropriate for IO and
   4010  *                   memory performance requirements
   4011  * @param crc callback to use to obtain response data
   4012  * @param crc_cls extra argument to @a crc
   4013  * @param crfc callback to call to free @a crc_cls resources
   4014  * @return NULL on error (i.e. invalid arguments, out of memory)
   4015  * @ingroup response
   4016  */
   4017 _MHD_EXTERN struct MHD_Response *
   4018 MHD_create_response_from_callback (uint64_t size,
   4019                                    size_t block_size,
   4020                                    MHD_ContentReaderCallback crc, void *crc_cls,
   4021                                    MHD_ContentReaderFreeCallback crfc);
   4022 
   4023 
   4024 /**
   4025  * Create a response object.
   4026  * The response object can be extended with header information and then be used
   4027  * any number of times.
   4028  *
   4029  * If response object is used to answer HEAD request then the body of the
   4030  * response is not used, while all headers (including automatic headers) are
   4031  * used.
   4032  *
   4033  * @param size size of the @a data portion of the response
   4034  * @param data the data itself
   4035  * @param must_free libmicrohttpd should free data when done
   4036  * @param must_copy libmicrohttpd must make a copy of @a data
   4037  *        right away, the data may be released anytime after
   4038  *        this call returns
   4039  * @return NULL on error (i.e. invalid arguments, out of memory)
   4040  * @deprecated use #MHD_create_response_from_buffer instead
   4041  * @ingroup response
   4042  */
   4043 _MHD_DEPR_FUNC ( \
   4044   "MHD_create_response_from_data() is deprecated, use MHD_create_response_from_buffer()" \
   4045   ) \
   4046   _MHD_EXTERN struct MHD_Response *
   4047 MHD_create_response_from_data (size_t size,
   4048                                void *data,
   4049                                int must_free,
   4050                                int must_copy);
   4051 
   4052 
   4053 /**
   4054  * Specification for how MHD should treat the memory buffer
   4055  * given for the response.
   4056  * @ingroup response
   4057  */
   4058 enum MHD_ResponseMemoryMode
   4059 {
   4060 
   4061   /**
   4062    * Buffer is a persistent (static/global) buffer that won't change
   4063    * for at least the lifetime of the response, MHD should just use
   4064    * it, not free it, not copy it, just keep an alias to it.
   4065    * @ingroup response
   4066    */
   4067   MHD_RESPMEM_PERSISTENT,
   4068 
   4069   /**
   4070    * Buffer is heap-allocated with `malloc()` (or equivalent) and
   4071    * should be freed by MHD after processing the response has
   4072    * concluded (response reference counter reaches zero).
   4073    * The more portable way to automatically free the buffer is function
   4074    * MHD_create_response_from_buffer_with_free_callback() with '&free' as
   4075    * crfc parameter as it does not require to use the same runtime library.
   4076    * @warning It is critical to make sure that the same C-runtime library
   4077    *          is used by both application and MHD (especially
   4078    *          important for W32).
   4079    * @ingroup response
   4080    */
   4081   MHD_RESPMEM_MUST_FREE,
   4082 
   4083   /**
   4084    * Buffer is in transient memory, but not on the heap (for example,
   4085    * on the stack or non-`malloc()` allocated) and only valid during the
   4086    * call to #MHD_create_response_from_buffer.  MHD must make its
   4087    * own private copy of the data for processing.
   4088    * @ingroup response
   4089    */
   4090   MHD_RESPMEM_MUST_COPY
   4091 
   4092 } _MHD_FIXED_ENUM;
   4093 
   4094 
   4095 /**
   4096  * Create a response object with the content of provided buffer used as
   4097  * the response body.
   4098  *
   4099  * The response object can be extended with header information and then
   4100  * be used any number of times.
   4101  *
   4102  * If response object is used to answer HEAD request then the body
   4103  * of the response is not used, while all headers (including automatic
   4104  * headers) are used.
   4105  *
   4106  * @param size size of the data portion of the response
   4107  * @param buffer size bytes containing the response's data portion
   4108  * @param mode flags for buffer management
   4109  * @return NULL on error (i.e. invalid arguments, out of memory)
   4110  * @ingroup response
   4111  */
   4112 _MHD_EXTERN struct MHD_Response *
   4113 MHD_create_response_from_buffer (size_t size,
   4114                                  void *buffer,
   4115                                  enum MHD_ResponseMemoryMode mode);
   4116 
   4117 
   4118 /**
   4119  * Create a response object with the content of provided statically allocated
   4120  * buffer used as the response body.
   4121  *
   4122  * The buffer must be valid for the lifetime of the response. The easiest way
   4123  * to achieve this is to use a statically allocated buffer.
   4124  *
   4125  * The response object can be extended with header information and then
   4126  * be used any number of times.
   4127  *
   4128  * If response object is used to answer HEAD request then the body
   4129  * of the response is not used, while all headers (including automatic
   4130  * headers) are used.
   4131  *
   4132  * @param size the size of the data in @a buffer, can be zero
   4133  * @param buffer the buffer with the data for the response body, can be NULL
   4134  *               if @a size is zero
   4135  * @return NULL on error (i.e. invalid arguments, out of memory)
   4136  * @note Available since #MHD_VERSION 0x00097701
   4137  * @ingroup response
   4138  */
   4139 _MHD_EXTERN struct MHD_Response *
   4140 MHD_create_response_from_buffer_static (size_t size,
   4141                                         const void *buffer);
   4142 
   4143 
   4144 /**
   4145  * Create a response object with the content of provided temporal buffer
   4146  * used as the response body.
   4147  *
   4148  * An internal copy of the buffer will be made automatically, so buffer have
   4149  * to be valid only during the call of this function (as a typical example:
   4150  * buffer is a local (non-static) array).
   4151  *
   4152  * The response object can be extended with header information and then
   4153  * be used any number of times.
   4154  *
   4155  * If response object is used to answer HEAD request then the body
   4156  * of the response is not used, while all headers (including automatic
   4157  * headers) are used.
   4158  *
   4159  * @param size the size of the data in @a buffer, can be zero
   4160  * @param buffer the buffer with the data for the response body, can be NULL
   4161  *               if @a size is zero
   4162  * @return NULL on error (i.e. invalid arguments, out of memory)
   4163  * @note Available since #MHD_VERSION 0x00097701
   4164  * @ingroup response
   4165  */
   4166 _MHD_EXTERN struct MHD_Response *
   4167 MHD_create_response_from_buffer_copy (size_t size,
   4168                                       const void *buffer);
   4169 
   4170 
   4171 /**
   4172  * Create a response object with the content of provided buffer used as
   4173  * the response body.
   4174  *
   4175  * The response object can be extended with header information and then
   4176  * be used any number of times.
   4177  *
   4178  * If response object is used to answer HEAD request then the body
   4179  * of the response is not used, while all headers (including automatic
   4180  * headers) are used.
   4181  *
   4182  * @param size size of the data portion of the response
   4183  * @param buffer size bytes containing the response's data portion
   4184  * @param crfc function to call to free the @a buffer
   4185  * @return NULL on error (i.e. invalid arguments, out of memory)
   4186  * @note Available since #MHD_VERSION 0x00096000
   4187  * @ingroup response
   4188  */
   4189 _MHD_EXTERN struct MHD_Response *
   4190 MHD_create_response_from_buffer_with_free_callback (size_t size,
   4191                                                     void *buffer,
   4192                                                     MHD_ContentReaderFreeCallback
   4193                                                     crfc);
   4194 
   4195 
   4196 /**
   4197  * Create a response object with the content of provided buffer used as
   4198  * the response body.
   4199  *
   4200  * The response object can be extended with header information and then
   4201  * be used any number of times.
   4202  *
   4203  * If response object is used to answer HEAD request then the body
   4204  * of the response is not used, while all headers (including automatic
   4205  * headers) are used.
   4206  *
   4207  * @param size size of the data portion of the response
   4208  * @param buffer size bytes containing the response's data portion
   4209  * @param crfc function to call to cleanup, if set to NULL then callback
   4210  *             is not called
   4211  * @param crfc_cls an argument for @a crfc
   4212  * @return NULL on error (i.e. invalid arguments, out of memory)
   4213  * @note Available since #MHD_VERSION 0x00097302
   4214  * @note 'const' qualifier is used for @a buffer since #MHD_VERSION 0x00097701
   4215  * @ingroup response
   4216  */
   4217 _MHD_EXTERN struct MHD_Response *
   4218 MHD_create_response_from_buffer_with_free_callback_cls (size_t size,
   4219                                                         const void *buffer,
   4220                                                         MHD_ContentReaderFreeCallback
   4221                                                         crfc,
   4222                                                         void *crfc_cls);
   4223 
   4224 
   4225 /**
   4226  * Create a response object with the content of provided file used as
   4227  * the response body.
   4228  *
   4229  * The response object can be extended with header information and then
   4230  * be used any number of times.
   4231  *
   4232  * If response object is used to answer HEAD request then the body
   4233  * of the response is not used, while all headers (including automatic
   4234  * headers) are used.
   4235  *
   4236  * @param size size of the data portion of the response
   4237  * @param fd file descriptor referring to a file on disk with the
   4238  *        data; will be closed when response is destroyed;
   4239  *        fd should be in 'blocking' mode
   4240  * @return NULL on error (i.e. invalid arguments, out of memory)
   4241  * @ingroup response
   4242  */
   4243 _MHD_EXTERN struct MHD_Response *
   4244 MHD_create_response_from_fd (size_t size,
   4245                              int fd);
   4246 
   4247 
   4248 /**
   4249  * Create a response object with the response body created by reading
   4250  * the provided pipe.
   4251  *
   4252  * The response object can be extended with header information and
   4253  * then be used ONLY ONCE.
   4254  *
   4255  * If response object is used to answer HEAD request then the body
   4256  * of the response is not used, while all headers (including automatic
   4257  * headers) are used.
   4258  *
   4259  * @param fd file descriptor referring to a read-end of a pipe with the
   4260  *        data; will be closed when response is destroyed;
   4261  *        fd should be in 'blocking' mode
   4262  * @return NULL on error (i.e. invalid arguments, out of memory)
   4263  * @note Available since #MHD_VERSION 0x00097102
   4264  * @ingroup response
   4265  */
   4266 _MHD_EXTERN struct MHD_Response *
   4267 MHD_create_response_from_pipe (int fd);
   4268 
   4269 
   4270 /**
   4271  * Create a response object with the content of provided file used as
   4272  * the response body.
   4273  *
   4274  * The response object can be extended with header information and then
   4275  * be used any number of times.
   4276  *
   4277  * If response object is used to answer HEAD request then the body
   4278  * of the response is not used, while all headers (including automatic
   4279  * headers) are used.
   4280  *
   4281  * @param size size of the data portion of the response;
   4282  *        sizes larger than 2 GiB may be not supported by OS or
   4283  *        MHD build; see ::MHD_FEATURE_LARGE_FILE
   4284  * @param fd file descriptor referring to a file on disk with the
   4285  *        data; will be closed when response is destroyed;
   4286  *        fd should be in 'blocking' mode
   4287  * @return NULL on error (i.e. invalid arguments, out of memory)
   4288  * @ingroup response
   4289  */
   4290 _MHD_EXTERN struct MHD_Response *
   4291 MHD_create_response_from_fd64 (uint64_t size,
   4292                                int fd);
   4293 
   4294 
   4295 /**
   4296  * Create a response object with the content of provided file with
   4297  * specified offset used as the response body.
   4298  *
   4299  * The response object can be extended with header information and then
   4300  * be used any number of times.
   4301  *
   4302  * If response object is used to answer HEAD request then the body
   4303  * of the response is not used, while all headers (including automatic
   4304  * headers) are used.
   4305  *
   4306  * @param size size of the data portion of the response
   4307  * @param fd file descriptor referring to a file on disk with the
   4308  *        data; will be closed when response is destroyed;
   4309  *        fd should be in 'blocking' mode
   4310  * @param offset offset to start reading from in the file;
   4311  *        Be careful! `off_t` may have been compiled to be a
   4312  *        64-bit variable for MHD, in which case your application
   4313  *        also has to be compiled using the same options! Read
   4314  *        the MHD manual for more details.
   4315  * @return NULL on error (i.e. invalid arguments, out of memory)
   4316  * @ingroup response
   4317  */
   4318 _MHD_DEPR_FUNC ( \
   4319   "Function MHD_create_response_from_fd_at_offset() is deprecated, use MHD_create_response_from_fd_at_offset64()" \
   4320   ) \
   4321   _MHD_EXTERN struct MHD_Response *
   4322 MHD_create_response_from_fd_at_offset (size_t size,
   4323                                        int fd,
   4324                                        off_t offset);
   4325 
   4326 #if ! defined(_MHD_NO_DEPR_IN_MACRO) || defined(_MHD_NO_DEPR_FUNC)
   4327 /* Substitute MHD_create_response_from_fd_at_offset64() instead of MHD_create_response_from_fd_at_offset()
   4328    to minimize potential problems with different off_t sizes */
   4329 #define MHD_create_response_from_fd_at_offset(size,fd,offset) \
   4330         _MHD_DEPR_IN_MACRO ( \
   4331           "Usage of MHD_create_response_from_fd_at_offset() is deprecated, use MHD_create_response_from_fd_at_offset64()") \
   4332         MHD_create_response_from_fd_at_offset64 ((size),(fd),(offset))
   4333 #endif /* !_MHD_NO_DEPR_IN_MACRO || _MHD_NO_DEPR_FUNC */
   4334 
   4335 
   4336 /**
   4337  * Create a response object with the content of provided file with
   4338  * specified offset used as the response body.
   4339  *
   4340  * The response object can be extended with header information and then
   4341  * be used any number of times.
   4342  *
   4343  * If response object is used to answer HEAD request then the body
   4344  * of the response is not used, while all headers (including automatic
   4345  * headers) are used.
   4346  *
   4347  * @param size size of the data portion of the response;
   4348  *        sizes larger than 2 GiB may be not supported by OS or
   4349  *        MHD build; see ::MHD_FEATURE_LARGE_FILE
   4350  * @param fd file descriptor referring to a file on disk with the
   4351  *        data; will be closed when response is destroyed;
   4352  *        fd should be in 'blocking' mode
   4353  * @param offset offset to start reading from in the file;
   4354  *        reading file beyond 2 GiB may be not supported by OS or
   4355  *        MHD build; see ::MHD_FEATURE_LARGE_FILE
   4356  * @return NULL on error (i.e. invalid arguments, out of memory)
   4357  * @ingroup response
   4358  */
   4359 _MHD_EXTERN struct MHD_Response *
   4360 MHD_create_response_from_fd_at_offset64 (uint64_t size,
   4361                                          int fd,
   4362                                          uint64_t offset);
   4363 
   4364 
   4365 /**
   4366  * Create a response object with an array of memory buffers
   4367  * used as the response body.
   4368  *
   4369  * The response object can be extended with header information and then
   4370  * be used any number of times.
   4371  *
   4372  * If response object is used to answer HEAD request then the body
   4373  * of the response is not used, while all headers (including automatic
   4374  * headers) are used.
   4375  *
   4376  * @param iov the array for response data buffers, an internal copy of this
   4377  *        will be made
   4378  * @param iovcnt the number of elements in @a iov
   4379  * @param free_cb the callback to clean up any data associated with @a iov when
   4380  *        the response is destroyed.
   4381  * @param cls the argument passed to @a free_cb
   4382  * @return NULL on error (i.e. invalid arguments, out of memory)
   4383  * @note Available since #MHD_VERSION 0x00097204
   4384  * @ingroup response
   4385  */
   4386 _MHD_EXTERN struct MHD_Response *
   4387 MHD_create_response_from_iovec (const struct MHD_IoVec *iov,
   4388                                 unsigned int iovcnt,
   4389                                 MHD_ContentReaderFreeCallback free_cb,
   4390                                 void *cls);
   4391 
   4392 
   4393 /**
   4394  * Create a response object with empty (zero size) body.
   4395  *
   4396  * The response object can be extended with header information and then be used
   4397  * any number of times.
   4398  *
   4399  * This function is a faster equivalent of #MHD_create_response_from_buffer call
   4400  * with zero size combined with call of #MHD_set_response_options.
   4401  *
   4402  * @param flags the flags for the new response object
   4403  * @return NULL on error (i.e. invalid arguments, out of memory),
   4404  *         the pointer to the created response object otherwise
   4405  * @note Available since #MHD_VERSION 0x00097701
   4406  * @ingroup response
   4407  */
   4408 _MHD_EXTERN struct MHD_Response *
   4409 MHD_create_response_empty (enum MHD_ResponseFlags flags);
   4410 
   4411 
   4412 /**
   4413  * Enumeration for actions MHD should perform on the underlying socket
   4414  * of the upgrade.  This API is not finalized, and in particular
   4415  * the final set of actions is yet to be decided. This is just an
   4416  * idea for what we might want.
   4417  */
   4418 enum MHD_UpgradeAction
   4419 {
   4420 
   4421   /**
   4422    * Close the socket, the application is done with it.
   4423    *
   4424    * Takes no extra arguments.
   4425    */
   4426   MHD_UPGRADE_ACTION_CLOSE = 0,
   4427 
   4428   /**
   4429    * Enable CORKing on the underlying socket.
   4430    */
   4431   MHD_UPGRADE_ACTION_CORK_ON = 1,
   4432 
   4433   /**
   4434    * Disable CORKing on the underlying socket.
   4435    */
   4436   MHD_UPGRADE_ACTION_CORK_OFF = 2
   4437 
   4438 } _MHD_FIXED_ENUM;
   4439 
   4440 
   4441 /**
   4442  * Handle given to the application to manage special
   4443  * actions relating to MHD responses that "upgrade"
   4444  * the HTTP protocol (i.e. to WebSockets).
   4445  */
   4446 struct MHD_UpgradeResponseHandle;
   4447 
   4448 
   4449 /**
   4450  * This connection-specific callback is provided by MHD to
   4451  * applications (unusual) during the #MHD_UpgradeHandler.
   4452  * It allows applications to perform 'special' actions on
   4453  * the underlying socket from the upgrade.
   4454  *
   4455  * @param urh the handle identifying the connection to perform
   4456  *            the upgrade @a action on.
   4457  * @param action which action should be performed
   4458  * @param ... arguments to the action (depends on the action)
   4459  * @return #MHD_NO on error, #MHD_YES on success
   4460  */
   4461 _MHD_EXTERN enum MHD_Result
   4462 MHD_upgrade_action (struct MHD_UpgradeResponseHandle *urh,
   4463                     enum MHD_UpgradeAction action,
   4464                     ...);
   4465 
   4466 
   4467 /**
   4468  * Function called after a protocol "upgrade" response was sent
   4469  * successfully and the socket should now be controlled by some
   4470  * protocol other than HTTP.
   4471  *
   4472  * Any data already received on the socket will be made available in
   4473  * @e extra_in.  This can happen if the application sent extra data
   4474  * before MHD send the upgrade response.  The application should
   4475  * treat data from @a extra_in as if it had read it from the socket.
   4476  *
   4477  * Note that the application must not close() @a sock directly,
   4478  * but instead use #MHD_upgrade_action() for special operations
   4479  * on @a sock.
   4480  *
   4481  * Data forwarding to "upgraded" @a sock will be started as soon
   4482  * as this function return.
   4483  *
   4484  * Except when in 'thread-per-connection' mode, implementations
   4485  * of this function should never block (as it will still be called
   4486  * from within the main event loop).
   4487  *
   4488  * @param cls closure, whatever was given to #MHD_create_response_for_upgrade().
   4489  * @param connection original HTTP connection handle,
   4490  *                   giving the function a last chance
   4491  *                   to inspect the original HTTP request
   4492  * @param req_cls last value left in `req_cls` of the `MHD_AccessHandlerCallback`
   4493  * @param extra_in if we happened to have read bytes after the
   4494  *                 HTTP header already (because the client sent
   4495  *                 more than the HTTP header of the request before
   4496  *                 we sent the upgrade response),
   4497  *                 these are the extra bytes already read from @a sock
   4498  *                 by MHD.  The application should treat these as if
   4499  *                 it had read them from @a sock.
   4500  * @param extra_in_size number of bytes in @a extra_in
   4501  * @param sock socket to use for bi-directional communication
   4502  *        with the client.  For HTTPS, this may not be a socket
   4503  *        that is directly connected to the client and thus certain
   4504  *        operations (TCP-specific setsockopt(), getsockopt(), etc.)
   4505  *        may not work as expected (as the socket could be from a
   4506  *        socketpair() or a TCP-loopback).  The application is expected
   4507  *        to perform read()/recv() and write()/send() calls on the socket.
   4508  *        The application may also call shutdown(), but must not call
   4509  *        close() directly.
   4510  * @param urh argument for #MHD_upgrade_action()s on this @a connection.
   4511  *        Applications must eventually use this callback to (indirectly)
   4512  *        perform the close() action on the @a sock.
   4513  */
   4514 typedef void
   4515 (*MHD_UpgradeHandler)(void *cls,
   4516                       struct MHD_Connection *connection,
   4517                       void *req_cls,
   4518                       const char *extra_in,
   4519                       size_t extra_in_size,
   4520                       MHD_socket sock,
   4521                       struct MHD_UpgradeResponseHandle *urh);
   4522 
   4523 
   4524 /**
   4525  * Create a response object that can be used for 101 UPGRADE
   4526  * responses, for example to implement WebSockets.  After sending the
   4527  * response, control over the data stream is given to the callback (which
   4528  * can then, for example, start some bi-directional communication).
   4529  * If the response is queued for multiple connections, the callback
   4530  * will be called for each connection.  The callback
   4531  * will ONLY be called after the response header was successfully passed
   4532  * to the OS; if there are communication errors before, the usual MHD
   4533  * connection error handling code will be performed.
   4534  *
   4535  * Setting the correct HTTP code (i.e. MHD_HTTP_SWITCHING_PROTOCOLS)
   4536  * and setting correct HTTP headers for the upgrade must be done
   4537  * manually (this way, it is possible to implement most existing
   4538  * WebSocket versions using this API; in fact, this API might be useful
   4539  * for any protocol switch, not just WebSockets).  Note that
   4540  * draft-ietf-hybi-thewebsocketprotocol-00 cannot be implemented this
   4541  * way as the header "HTTP/1.1 101 WebSocket Protocol Handshake"
   4542  * cannot be generated; instead, MHD will always produce "HTTP/1.1 101
   4543  * Switching Protocols" (if the response code 101 is used).
   4544  *
   4545  * As usual, the response object can be extended with header
   4546  * information and then be used any number of times (as long as the
   4547  * header information is not connection-specific).
   4548  *
   4549  * @param upgrade_handler function to call with the "upgraded" socket
   4550  * @param upgrade_handler_cls closure for @a upgrade_handler
   4551  * @return NULL on error (i.e. invalid arguments, out of memory)
   4552  */
   4553 _MHD_EXTERN struct MHD_Response *
   4554 MHD_create_response_for_upgrade (MHD_UpgradeHandler upgrade_handler,
   4555                                  void *upgrade_handler_cls);
   4556 
   4557 
   4558 /**
   4559  * Destroy a response object and associated resources.  Note that
   4560  * libmicrohttpd may keep some of the resources around if the response
   4561  * is still in the queue for some clients, so the memory may not
   4562  * necessarily be freed immediately.
   4563  *
   4564  * @param response response to destroy
   4565  * @ingroup response
   4566  */
   4567 _MHD_EXTERN void
   4568 MHD_destroy_response (struct MHD_Response *response);
   4569 
   4570 
   4571 /**
   4572  * Add a header line to the response.
   4573  *
   4574  * When reply is generated with queued response, some headers are generated
   4575  * automatically. Automatically generated headers are only sent to the client,
   4576  * but not added back to the response object.
   4577  *
   4578  * The list of automatic headers:
   4579  * + "Date" header is added automatically unless already set by
   4580  *   this function
   4581  *   @see #MHD_USE_SUPPRESS_DATE_NO_CLOCK
   4582  * + "Content-Length" is added automatically when required, attempt to set
   4583  *   it manually by this function is ignored.
   4584  *   @see #MHD_RF_INSANITY_HEADER_CONTENT_LENGTH
   4585  * + "Transfer-Encoding" with value "chunked" is added automatically,
   4586  *   when chunked transfer encoding is used automatically. Same header with
   4587  *   the same value can be set manually by this function to enforce chunked
   4588  *   encoding, however for HTTP/1.0 clients chunked encoding will not be used
   4589  *   and manually set "Transfer-Encoding" header is automatically removed
   4590  *   for HTTP/1.0 clients
   4591  * + "Connection" may be added automatically with value "Keep-Alive" (only
   4592  *   for HTTP/1.0 clients) or "Close". The header "Connection" with value
   4593  *   "Close" could be set by this function to enforce closure of
   4594  *   the connection after sending this response. "Keep-Alive" cannot be
   4595  *   enforced and will be removed automatically.
   4596  *   @see #MHD_RF_SEND_KEEP_ALIVE_HEADER
   4597  *
   4598  * Some headers are pre-processed by this function:
   4599  * * "Connection" headers are combined into single header entry, value is
   4600  *   normilised, "Keep-Alive" tokens are removed.
   4601  * * "Transfer-Encoding" header: the only one header is allowed, the only
   4602  *   allowed value is "chunked".
   4603  * * "Date" header: the only one header is allowed, the second added header
   4604  *   replaces the first one.
   4605  * * "Content-Length" application-defined header is not allowed.
   4606  *   @see #MHD_RF_INSANITY_HEADER_CONTENT_LENGTH
   4607  *
   4608  * Headers are used in order as they were added.
   4609  *
   4610  * @param response the response to add a header to
   4611  * @param header the header name to add, no need to be static, an internal copy
   4612  *               will be created automatically
   4613  * @param content the header value to add, no need to be static, an internal
   4614  *                copy will be created automatically
   4615  * @return #MHD_YES on success,
   4616  *         #MHD_NO on error (i.e. invalid header or content format),
   4617  *         or out of memory
   4618  * @ingroup response
   4619  */
   4620 _MHD_EXTERN enum MHD_Result
   4621 MHD_add_response_header (struct MHD_Response *response,
   4622                          const char *header,
   4623                          const char *content);
   4624 
   4625 
   4626 /**
   4627  * Add a footer line to the response.
   4628  *
   4629  * @param response response to remove a header from
   4630  * @param footer the footer to delete
   4631  * @param content value to delete
   4632  * @return #MHD_NO on error (i.e. invalid footer or content format).
   4633  * @ingroup response
   4634  */
   4635 _MHD_EXTERN enum MHD_Result
   4636 MHD_add_response_footer (struct MHD_Response *response,
   4637                          const char *footer,
   4638                          const char *content);
   4639 
   4640 
   4641 /**
   4642  * Delete a header (or footer) line from the response.
   4643  *
   4644  * For "Connection" headers this function remove all tokens from existing
   4645  * value. Successful result means that at least one token has been removed.
   4646  * If all tokens are removed from "Connection" header, the empty "Connection"
   4647  * header removed.
   4648  *
   4649  * @param response response to remove a header from
   4650  * @param header the header to delete
   4651  * @param content value to delete
   4652  * @return #MHD_NO on error (no such header known)
   4653  * @ingroup response
   4654  */
   4655 _MHD_EXTERN enum MHD_Result
   4656 MHD_del_response_header (struct MHD_Response *response,
   4657                          const char *header,
   4658                          const char *content);
   4659 
   4660 
   4661 /**
   4662  * Get all of the headers (and footers) added to a response.
   4663  *
   4664  * @param response response to query
   4665  * @param iterator callback to call on each header;
   4666  *        may be NULL (then just count headers)
   4667  * @param iterator_cls extra argument to @a iterator
   4668  * @return number of entries iterated over
   4669  * @ingroup response
   4670  */
   4671 _MHD_EXTERN int
   4672 MHD_get_response_headers (struct MHD_Response *response,
   4673                           MHD_KeyValueIterator iterator,
   4674                           void *iterator_cls);
   4675 
   4676 
   4677 /**
   4678  * Get a particular header (or footer) from the response.
   4679  *
   4680  * @param response response to query
   4681  * @param key which header to get
   4682  * @return NULL if header does not exist
   4683  * @ingroup response
   4684  */
   4685 _MHD_EXTERN const char *
   4686 MHD_get_response_header (struct MHD_Response *response,
   4687                          const char *key);
   4688 
   4689 
   4690 /* ********************** PostProcessor functions ********************** */
   4691 
   4692 /**
   4693  * Create a `struct MHD_PostProcessor`.
   4694  *
   4695  * A `struct MHD_PostProcessor` can be used to (incrementally) parse
   4696  * the data portion of a POST request.  Note that some buggy browsers
   4697  * fail to set the encoding type.  If you want to support those, you
   4698  * may have to call #MHD_set_connection_value with the proper encoding
   4699  * type before creating a post processor (if no supported encoding
   4700  * type is set, this function will fail).
   4701  *
   4702  * @param connection the connection on which the POST is
   4703  *        happening (used to determine the POST format)
   4704  * @param buffer_size maximum number of bytes to use for
   4705  *        internal buffering (used only for the parsing,
   4706  *        specifically the parsing of the keys).  A
   4707  *        tiny value (256-1024) should be sufficient.
   4708  *        Do NOT use a value smaller than 256.  For good
   4709  *        performance, use 32 or 64k (i.e. 65536).
   4710  * @param iter iterator to be called with the parsed data,
   4711  *        Must NOT be NULL.
   4712  * @param iter_cls first argument to @a iter
   4713  * @return NULL on error (out of memory, unsupported encoding),
   4714  *         otherwise a PP handle
   4715  * @ingroup request
   4716  */
   4717 _MHD_EXTERN struct MHD_PostProcessor *
   4718 MHD_create_post_processor (struct MHD_Connection *connection,
   4719                            size_t buffer_size,
   4720                            MHD_PostDataIterator iter, void *iter_cls);
   4721 
   4722 
   4723 /**
   4724  * Parse and process POST data.  Call this function when POST data is
   4725  * available (usually during an #MHD_AccessHandlerCallback) with the
   4726  * "upload_data" and "upload_data_size".  Whenever possible, this will
   4727  * then cause calls to the #MHD_PostDataIterator.
   4728  *
   4729  * @param pp the post processor
   4730  * @param post_data @a post_data_len bytes of POST data
   4731  * @param post_data_len length of @a post_data
   4732  * @return #MHD_YES on success, #MHD_NO on error
   4733  *         (out-of-memory, iterator aborted, parse error)
   4734  * @ingroup request
   4735  */
   4736 _MHD_EXTERN enum MHD_Result
   4737 MHD_post_process (struct MHD_PostProcessor *pp,
   4738                   const char *post_data,
   4739                   size_t post_data_len);
   4740 
   4741 
   4742 /**
   4743  * Release PostProcessor resources.
   4744  *
   4745  * @param pp the PostProcessor to destroy
   4746  * @return #MHD_YES if processing completed nicely,
   4747  *         #MHD_NO if there were spurious characters / formatting
   4748  *                problems; it is common to ignore the return
   4749  *                value of this function
   4750  * @ingroup request
   4751  */
   4752 _MHD_EXTERN enum MHD_Result
   4753 MHD_destroy_post_processor (struct MHD_PostProcessor *pp);
   4754 
   4755 
   4756 /* ********************* Digest Authentication functions *************** */
   4757 
   4758 
   4759 /**
   4760  * Length of the binary output of the MD5 hash function.
   4761  * @sa #MHD_digest_get_hash_size()
   4762  * @ingroup authentication
   4763  */
   4764 #define MHD_MD5_DIGEST_SIZE 16
   4765 
   4766 /**
   4767  * Length of the binary output of the SHA-256 hash function.
   4768  * @sa #MHD_digest_get_hash_size()
   4769  * @ingroup authentication
   4770  */
   4771 #define MHD_SHA256_DIGEST_SIZE 32
   4772 
   4773 /**
   4774  * Length of the binary output of the SHA-512/256 hash function.
   4775  * @warning While this value is the same as the #MHD_SHA256_DIGEST_SIZE,
   4776  *          the calculated digests for SHA-256 and SHA-512/256 are different.
   4777  * @sa #MHD_digest_get_hash_size()
   4778  * @note Available since #MHD_VERSION 0x00097701
   4779  * @ingroup authentication
   4780  */
   4781 #define MHD_SHA512_256_DIGEST_SIZE 32
   4782 
   4783 /**
   4784  * Base type of hash calculation.
   4785  * Used as part of #MHD_DigestAuthAlgo3 values.
   4786  *
   4787  * @warning Not used directly by MHD API.
   4788  * @note Available since #MHD_VERSION 0x00097701
   4789  */
   4790 enum MHD_DigestBaseAlgo
   4791 {
   4792   /**
   4793    * Invalid hash algorithm value
   4794    */
   4795   MHD_DIGEST_BASE_ALGO_INVALID = 0,
   4796 
   4797   /**
   4798    * MD5 hash algorithm.
   4799    * As specified by RFC1321
   4800    */
   4801   MHD_DIGEST_BASE_ALGO_MD5 = (1 << 0),
   4802 
   4803   /**
   4804    * SHA-256 hash algorithm.
   4805    * As specified by FIPS PUB 180-4
   4806    */
   4807   MHD_DIGEST_BASE_ALGO_SHA256 = (1 << 1),
   4808 
   4809   /**
   4810    * SHA-512/256 hash algorithm.
   4811    * As specified by FIPS PUB 180-4
   4812    */
   4813   MHD_DIGEST_BASE_ALGO_SHA512_256 = (1 << 2)
   4814 } _MHD_FIXED_FLAGS_ENUM;
   4815 
   4816 /**
   4817  * The flag indicating non-session algorithm types,
   4818  * like 'MD5', 'SHA-256' or 'SHA-512-256'.
   4819  * @note Available since #MHD_VERSION 0x00097701
   4820  */
   4821 #define MHD_DIGEST_AUTH_ALGO3_NON_SESSION    (1 << 6)
   4822 
   4823 /**
   4824  * The flag indicating session algorithm types,
   4825  * like 'MD5-sess', 'SHA-256-sess' or 'SHA-512-256-sess'.
   4826  * @note Available since #MHD_VERSION 0x00097701
   4827  */
   4828 #define MHD_DIGEST_AUTH_ALGO3_SESSION        (1 << 7)
   4829 
   4830 /**
   4831  * Digest algorithm identification
   4832  * @warning Do not be confused with #MHD_DigestAuthAlgorithm,
   4833  *          which uses other values!
   4834  * @note Available since #MHD_VERSION 0x00097701
   4835  */
   4836 enum MHD_DigestAuthAlgo3
   4837 {
   4838   /**
   4839    * Unknown or wrong algorithm type.
   4840    * Used in struct MHD_DigestAuthInfo to indicate client value that
   4841    * cannot by identified.
   4842    */
   4843   MHD_DIGEST_AUTH_ALGO3_INVALID = 0,
   4844 
   4845   /**
   4846    * The 'MD5' algorithm, non-session version.
   4847    */
   4848   MHD_DIGEST_AUTH_ALGO3_MD5 =
   4849     MHD_DIGEST_BASE_ALGO_MD5 | MHD_DIGEST_AUTH_ALGO3_NON_SESSION,
   4850 
   4851   /**
   4852    * The 'MD5-sess' algorithm.
   4853    * Not supported by MHD for authentication.
   4854    */
   4855   MHD_DIGEST_AUTH_ALGO3_MD5_SESSION =
   4856     MHD_DIGEST_BASE_ALGO_MD5 | MHD_DIGEST_AUTH_ALGO3_SESSION,
   4857 
   4858   /**
   4859    * The 'SHA-256' algorithm, non-session version.
   4860    */
   4861   MHD_DIGEST_AUTH_ALGO3_SHA256 =
   4862     MHD_DIGEST_BASE_ALGO_SHA256 | MHD_DIGEST_AUTH_ALGO3_NON_SESSION,
   4863 
   4864   /**
   4865    * The 'SHA-256-sess' algorithm.
   4866    * Not supported by MHD for authentication.
   4867    */
   4868   MHD_DIGEST_AUTH_ALGO3_SHA256_SESSION =
   4869     MHD_DIGEST_BASE_ALGO_SHA256 | MHD_DIGEST_AUTH_ALGO3_SESSION,
   4870 
   4871   /**
   4872    * The 'SHA-512-256' (SHA-512/256) algorithm.
   4873    */
   4874   MHD_DIGEST_AUTH_ALGO3_SHA512_256 =
   4875     MHD_DIGEST_BASE_ALGO_SHA512_256 | MHD_DIGEST_AUTH_ALGO3_NON_SESSION,
   4876 
   4877   /**
   4878    * The 'SHA-512-256-sess' (SHA-512/256 session) algorithm.
   4879    * Not supported by MHD for authentication.
   4880    */
   4881   MHD_DIGEST_AUTH_ALGO3_SHA512_256_SESSION =
   4882     MHD_DIGEST_BASE_ALGO_SHA512_256 | MHD_DIGEST_AUTH_ALGO3_SESSION
   4883 };
   4884 
   4885 
   4886 /**
   4887  * Get digest size for specified algorithm.
   4888  *
   4889  * The size of the digest specifies the size of the userhash, userdigest
   4890  * and other parameters which size depends on used hash algorithm.
   4891  * @param algo3 the algorithm to check
   4892  * @return the size of the digest (either #MHD_MD5_DIGEST_SIZE or
   4893  *         #MHD_SHA256_DIGEST_SIZE/MHD_SHA512_256_DIGEST_SIZE)
   4894  *         or zero if the input value is not supported or not valid
   4895  * @sa #MHD_digest_auth_calc_userdigest()
   4896  * @sa #MHD_digest_auth_calc_userhash(), #MHD_digest_auth_calc_userhash_hex()
   4897  * @note Available since #MHD_VERSION 0x00097701
   4898  * @ingroup authentication
   4899  */
   4900 _MHD_EXTERN size_t
   4901 MHD_digest_get_hash_size (enum MHD_DigestAuthAlgo3 algo3);
   4902 
   4903 /**
   4904  * Digest algorithm identification, allow multiple selection.
   4905  *
   4906  * #MHD_DigestAuthAlgo3 always can be casted to #MHD_DigestAuthMultiAlgo3, but
   4907  * not vice versa.
   4908  *
   4909  * @note Available since #MHD_VERSION 0x00097701
   4910  */
   4911 enum MHD_DigestAuthMultiAlgo3
   4912 {
   4913   /**
   4914    * Unknown or wrong algorithm type.
   4915    */
   4916   MHD_DIGEST_AUTH_MULT_ALGO3_INVALID = MHD_DIGEST_AUTH_ALGO3_INVALID,
   4917 
   4918   /**
   4919    * The 'MD5' algorithm, non-session version.
   4920    */
   4921   MHD_DIGEST_AUTH_MULT_ALGO3_MD5 = MHD_DIGEST_AUTH_ALGO3_MD5,
   4922 
   4923   /**
   4924    * The 'MD5-sess' algorithm.
   4925    * Not supported by MHD for authentication.
   4926    * Reserved value.
   4927    */
   4928   MHD_DIGEST_AUTH_MULT_ALGO3_MD5_SESSION = MHD_DIGEST_AUTH_ALGO3_MD5_SESSION,
   4929 
   4930   /**
   4931    * The 'SHA-256' algorithm, non-session version.
   4932    */
   4933   MHD_DIGEST_AUTH_MULT_ALGO3_SHA256 = MHD_DIGEST_AUTH_ALGO3_SHA256,
   4934 
   4935   /**
   4936    * The 'SHA-256-sess' algorithm.
   4937    * Not supported by MHD for authentication.
   4938    * Reserved value.
   4939    */
   4940   MHD_DIGEST_AUTH_MULT_ALGO3_SHA256_SESSION =
   4941     MHD_DIGEST_AUTH_ALGO3_SHA256_SESSION,
   4942 
   4943   /**
   4944    * The 'SHA-512-256' (SHA-512/256) algorithm, non-session version.
   4945    */
   4946   MHD_DIGEST_AUTH_MULT_ALGO3_SHA512_256 = MHD_DIGEST_AUTH_ALGO3_SHA512_256,
   4947 
   4948   /**
   4949    * The 'SHA-512-256-sess' (SHA-512/256 session) algorithm.
   4950    * Not supported by MHD for authentication.
   4951    * Reserved value.
   4952    */
   4953   MHD_DIGEST_AUTH_MULT_ALGO3_SHA512_256_SESSION =
   4954     MHD_DIGEST_AUTH_ALGO3_SHA512_256_SESSION,
   4955 
   4956   /**
   4957    * SHA-256 or SHA-512/256 non-session algorithm, MHD will choose
   4958    * the preferred or the matching one.
   4959    */
   4960   MHD_DIGEST_AUTH_MULT_ALGO3_SHA_ANY_NON_SESSION =
   4961     MHD_DIGEST_AUTH_ALGO3_SHA256 | MHD_DIGEST_AUTH_ALGO3_SHA512_256,
   4962 
   4963   /**
   4964    * Any non-session algorithm, MHD will choose the preferred or
   4965    * the matching one.
   4966    */
   4967   MHD_DIGEST_AUTH_MULT_ALGO3_ANY_NON_SESSION =
   4968     (0x3F) | MHD_DIGEST_AUTH_ALGO3_NON_SESSION,
   4969 
   4970   /**
   4971    * The SHA-256 or SHA-512/256 session algorithm.
   4972    * Not supported by MHD.
   4973    * Reserved value.
   4974    */
   4975   MHD_DIGEST_AUTH_MULT_ALGO3_SHA_ANY_SESSION =
   4976     MHD_DIGEST_AUTH_ALGO3_SHA256_SESSION
   4977     | MHD_DIGEST_AUTH_ALGO3_SHA512_256_SESSION,
   4978 
   4979   /**
   4980    * Any session algorithm.
   4981    * Not supported by MHD.
   4982    * Reserved value.
   4983    */
   4984   MHD_DIGEST_AUTH_MULT_ALGO3_ANY_SESSION =
   4985     (0x3F) | MHD_DIGEST_AUTH_ALGO3_SESSION,
   4986 
   4987   /**
   4988    * The MD5 algorithm, session or non-session.
   4989    * Currently supported as non-session only.
   4990    */
   4991   MHD_DIGEST_AUTH_MULT_ALGO3_MD5_ANY =
   4992     MHD_DIGEST_AUTH_MULT_ALGO3_MD5 | MHD_DIGEST_AUTH_MULT_ALGO3_MD5_SESSION,
   4993 
   4994   /**
   4995    * The SHA-256 algorithm, session or non-session.
   4996    * Currently supported as non-session only.
   4997    */
   4998   MHD_DIGEST_AUTH_MULT_ALGO3_SHA256_ANY =
   4999     MHD_DIGEST_AUTH_MULT_ALGO3_SHA256
   5000     | MHD_DIGEST_AUTH_MULT_ALGO3_SHA256_SESSION,
   5001 
   5002   /**
   5003    * The SHA-512/256 algorithm, session or non-session.
   5004    * Currently supported as non-session only.
   5005    */
   5006   MHD_DIGEST_AUTH_MULT_ALGO3_SHA512_256_ANY =
   5007     MHD_DIGEST_AUTH_MULT_ALGO3_SHA512_256
   5008     | MHD_DIGEST_AUTH_MULT_ALGO3_SHA512_256_SESSION,
   5009 
   5010   /**
   5011    * The SHA-256 or SHA-512/256 algorithm, session or non-session.
   5012    * Currently supported as non-session only.
   5013    */
   5014   MHD_DIGEST_AUTH_MULT_ALGO3_SHA_ANY_ANY =
   5015     MHD_DIGEST_AUTH_MULT_ALGO3_SHA_ANY_NON_SESSION
   5016     | MHD_DIGEST_AUTH_MULT_ALGO3_SHA_ANY_SESSION,
   5017 
   5018   /**
   5019    * Any algorithm, MHD will choose the preferred or the matching one.
   5020    */
   5021   MHD_DIGEST_AUTH_MULT_ALGO3_ANY =
   5022     (0x3F) | MHD_DIGEST_AUTH_ALGO3_NON_SESSION | MHD_DIGEST_AUTH_ALGO3_SESSION
   5023 };
   5024 
   5025 
   5026 /**
   5027  * Calculate "userhash", return it as binary data.
   5028  *
   5029  * The "userhash" is the hash of the string "username:realm".
   5030  *
   5031  * The "userhash" could be used to avoid sending username in cleartext in Digest
   5032  * Authorization client's header.
   5033  *
   5034  * Userhash is not designed to hide the username in local database or files,
   5035  * as username in cleartext is required for #MHD_digest_auth_check3() function
   5036  * to check the response, but it can be used to hide username in HTTP headers.
   5037  *
   5038  * This function could be used when the new username is added to the username
   5039  * database to save the "userhash" alongside with the username (preferably) or
   5040  * when loading list of the usernames to generate the userhash for every loaded
   5041  * username (this will cause delays at the start with the long lists).
   5042  *
   5043  * Once "userhash" is generated it could be used to identify users by clients
   5044  * with "userhash" support.
   5045  * Avoid repetitive usage of this function for the same username/realm
   5046  * combination as it will cause excessive CPU load; save and re-use the result
   5047  * instead.
   5048  *
   5049  * @param algo3 the algorithm for userhash calculations
   5050  * @param username the username
   5051  * @param realm the realm
   5052  * @param[out] userhash_bin the output buffer for userhash as binary data;
   5053  *                          if this function succeeds, then this buffer has
   5054  *                          #MHD_digest_get_hash_size(algo3) bytes of userhash
   5055  *                          upon return
   5056  * @param bin_buf_size the size of the @a userhash_bin buffer, must be
   5057  *                     at least #MHD_digest_get_hash_size(algo3) bytes long
   5058  * @return MHD_YES on success,
   5059  *         MHD_NO if @a bin_buf_size is too small or if @a algo3 algorithm is
   5060  *         not supported (or external error has occurred,
   5061  *         see #MHD_FEATURE_EXTERN_HASH)
   5062  * @sa #MHD_digest_auth_calc_userhash_hex()
   5063  * @note Available since #MHD_VERSION 0x00097701
   5064  * @ingroup authentication
   5065  */
   5066 _MHD_EXTERN enum MHD_Result
   5067 MHD_digest_auth_calc_userhash (enum MHD_DigestAuthAlgo3 algo3,
   5068                                const char *username,
   5069                                const char *realm,
   5070                                void *userhash_bin,
   5071                                size_t bin_buf_size);
   5072 
   5073 
   5074 /**
   5075  * Calculate "userhash", return it as hexadecimal string.
   5076  *
   5077  * The "userhash" is the hash of the string "username:realm".
   5078  *
   5079  * The "userhash" could be used to avoid sending username in cleartext in Digest
   5080  * Authorization client's header.
   5081  *
   5082  * Userhash is not designed to hide the username in local database or files,
   5083  * as username in cleartext is required for #MHD_digest_auth_check3() function
   5084  * to check the response, but it can be used to hide username in HTTP headers.
   5085  *
   5086  * This function could be used when the new username is added to the username
   5087  * database to save the "userhash" alongside with the username (preferably) or
   5088  * when loading list of the usernames to generate the userhash for every loaded
   5089  * username (this will cause delays at the start with the long lists).
   5090  *
   5091  * Once "userhash" is generated it could be used to identify users by clients
   5092  * with "userhash" support.
   5093  * Avoid repetitive usage of this function for the same username/realm
   5094  * combination as it will cause excessive CPU load; save and re-use the result
   5095  * instead.
   5096  *
   5097  * @param algo3 the algorithm for userhash calculations
   5098  * @param username the username
   5099  * @param realm the realm
   5100  * @param[out] userhash_hex the output buffer for userhash as hex string;
   5101  *                          if this function succeeds, then this buffer has
   5102  *                          #MHD_digest_get_hash_size(algo3)*2 chars long
   5103  *                          userhash zero-terminated string
   5104  * @param bin_buf_size the size of the @a userhash_bin buffer, must be
   5105  *                     at least #MHD_digest_get_hash_size(algo3)*2+1 chars long
   5106  * @return MHD_YES on success,
   5107  *         MHD_NO if @a bin_buf_size is too small or if @a algo3 algorithm is
   5108  *         not supported (or external error has occurred,
   5109  *         see #MHD_FEATURE_EXTERN_HASH).
   5110  * @sa #MHD_digest_auth_calc_userhash()
   5111  * @note Available since #MHD_VERSION 0x00097701
   5112  * @ingroup authentication
   5113  */
   5114 _MHD_EXTERN enum MHD_Result
   5115 MHD_digest_auth_calc_userhash_hex (enum MHD_DigestAuthAlgo3 algo3,
   5116                                    const char *username,
   5117                                    const char *realm,
   5118                                    char *userhash_hex,
   5119                                    size_t hex_buf_size);
   5120 
   5121 
   5122 /**
   5123  * The type of username used by client in Digest Authorization header
   5124  *
   5125  * Values are sorted so simplified checks could be used.
   5126  * For example:
   5127  * * (value <= MHD_DIGEST_AUTH_UNAME_TYPE_INVALID) is true if no valid username
   5128  *   is provided by the client
   5129  * * (value >= MHD_DIGEST_AUTH_UNAME_TYPE_USERHASH) is true if username is
   5130  *   provided in any form
   5131  * * (value >= MHD_DIGEST_AUTH_UNAME_TYPE_STANDARD) is true if username is
   5132  *   provided in clear text (no userhash matching is needed)
   5133  *
   5134  * @note Available since #MHD_VERSION 0x00097701
   5135  */
   5136 enum MHD_DigestAuthUsernameType
   5137 {
   5138   /**
   5139    * No username parameter in in Digest Authorization header.
   5140    * This should be treated as an error.
   5141    */
   5142   MHD_DIGEST_AUTH_UNAME_TYPE_MISSING = 0,
   5143 
   5144   /**
   5145    * The 'username' parameter is used to specify the username.
   5146    */
   5147   MHD_DIGEST_AUTH_UNAME_TYPE_STANDARD = (1 << 2),
   5148 
   5149   /**
   5150    * The username is specified by 'username*' parameter with
   5151    * the extended notation (see RFC 5987 #section-3.2.1).
   5152    * The only difference between standard and extended types is
   5153    * the way how username value is encoded in the header.
   5154    */
   5155   MHD_DIGEST_AUTH_UNAME_TYPE_EXTENDED = (1 << 3),
   5156 
   5157   /**
   5158    * The username provided in form of 'userhash' as
   5159    * specified by RFC 7616 #section-3.4.4.
   5160    * @sa #MHD_digest_auth_calc_userhash_hex(), #MHD_digest_auth_calc_userhash()
   5161    */
   5162   MHD_DIGEST_AUTH_UNAME_TYPE_USERHASH = (1 << 1),
   5163 
   5164   /**
   5165    * The invalid combination of username parameters are used by client.
   5166    * Either:
   5167    * * both 'username' and 'username*' are used
   5168    * * 'username*' is used with 'userhash=true'
   5169    * * 'username*' used with invalid extended notation
   5170    * * 'username' is not hexadecimal string, while 'userhash' set to 'true'
   5171    */
   5172   MHD_DIGEST_AUTH_UNAME_TYPE_INVALID = (1 << 0)
   5173 } _MHD_FIXED_ENUM;
   5174 
   5175 /**
   5176  * The QOP ('quality of protection') types.
   5177  * @note Available since #MHD_VERSION 0x00097701
   5178  */
   5179 enum MHD_DigestAuthQOP
   5180 {
   5181   /**
   5182    * Invalid/unknown QOP.
   5183    * Used in struct MHD_DigestAuthInfo to indicate client value that
   5184    * cannot by identified.
   5185    */
   5186   MHD_DIGEST_AUTH_QOP_INVALID = 0,
   5187 
   5188   /**
   5189    * No QOP parameter.
   5190    * As described in old RFC 2069 original specification.
   5191    * This mode is not allowed by latest RFCs and should be used only to
   5192    * communicate with clients that do not support more modern modes (with QOP
   5193    * parameter).
   5194    * This mode is less secure than other modes and inefficient.
   5195    */
   5196   MHD_DIGEST_AUTH_QOP_NONE = 1 << 0,
   5197 
   5198   /**
   5199    * The 'auth' QOP type.
   5200    */
   5201   MHD_DIGEST_AUTH_QOP_AUTH = 1 << 1,
   5202 
   5203   /**
   5204    * The 'auth-int' QOP type.
   5205    * Not supported by MHD for authentication.
   5206    */
   5207   MHD_DIGEST_AUTH_QOP_AUTH_INT = 1 << 2
   5208 } _MHD_FIXED_FLAGS_ENUM;
   5209 
   5210 /**
   5211  * The QOP ('quality of protection') types, multiple selection.
   5212  *
   5213  * #MHD_DigestAuthQOP always can be casted to #MHD_DigestAuthMultiQOP, but
   5214  * not vice versa.
   5215  *
   5216  * @note Available since #MHD_VERSION 0x00097701
   5217  */
   5218 enum MHD_DigestAuthMultiQOP
   5219 {
   5220   /**
   5221    * Invalid/unknown QOP.
   5222    */
   5223   MHD_DIGEST_AUTH_MULT_QOP_INVALID = MHD_DIGEST_AUTH_QOP_INVALID,
   5224 
   5225   /**
   5226    * No QOP parameter.
   5227    * As described in old RFC 2069 original specification.
   5228    * This mode is not allowed by latest RFCs and should be used only to
   5229    * communicate with clients that do not support more modern modes (with QOP
   5230    * parameter).
   5231    * This mode is less secure than other modes and inefficient.
   5232    */
   5233   MHD_DIGEST_AUTH_MULT_QOP_NONE = MHD_DIGEST_AUTH_QOP_NONE,
   5234 
   5235   /**
   5236    * The 'auth' QOP type.
   5237    */
   5238   MHD_DIGEST_AUTH_MULT_QOP_AUTH = MHD_DIGEST_AUTH_QOP_AUTH,
   5239 
   5240   /**
   5241    * The 'auth-int' QOP type.
   5242    * Not supported by MHD.
   5243    * Reserved value.
   5244    */
   5245   MHD_DIGEST_AUTH_MULT_QOP_AUTH_INT = MHD_DIGEST_AUTH_QOP_AUTH_INT,
   5246 
   5247   /**
   5248    * The 'auth' QOP type OR the old RFC2069 (no QOP) type.
   5249    * In other words: any types except 'auth-int'.
   5250    * RFC2069-compatible mode is allowed, thus this value should be used only
   5251    * when it is really necessary.
   5252    */
   5253   MHD_DIGEST_AUTH_MULT_QOP_ANY_NON_INT =
   5254     MHD_DIGEST_AUTH_QOP_NONE | MHD_DIGEST_AUTH_QOP_AUTH,
   5255 
   5256   /**
   5257    * Any 'auth' QOP type ('auth' or 'auth-int').
   5258    * Currently supported as 'auth' QOP type only.
   5259    */
   5260   MHD_DIGEST_AUTH_MULT_QOP_AUTH_ANY =
   5261     MHD_DIGEST_AUTH_QOP_AUTH | MHD_DIGEST_AUTH_QOP_AUTH_INT
   5262 } _MHD_FIXED_ENUM;
   5263 
   5264 /**
   5265  * The invalid value of 'nc' parameter in client Digest Authorization header.
   5266  * @note Available since #MHD_VERSION 0x00097701
   5267  */
   5268 #define MHD_DIGEST_AUTH_INVALID_NC_VALUE        (0)
   5269 
   5270 /**
   5271  * Information from Digest Authorization client's header.
   5272  *
   5273  * All buffers pointed by any struct members are freed when #MHD_free() is
   5274  * called for pointer to this structure.
   5275  *
   5276  * Application may modify buffers as needed until #MHD_free() is called for
   5277  * pointer to this structure
   5278  * @note Available since #MHD_VERSION 0x00097701
   5279  */
   5280 struct MHD_DigestAuthInfo
   5281 {
   5282   /**
   5283    * The algorithm as defined by client.
   5284    * Set automatically to MD5 if not specified by client.
   5285    * @warning Do not be confused with #MHD_DigestAuthAlgorithm,
   5286    *          which uses other values!
   5287    */
   5288   enum MHD_DigestAuthAlgo3 algo3;
   5289 
   5290   /**
   5291    * The type of username used by client.
   5292    */
   5293   enum MHD_DigestAuthUsernameType uname_type;
   5294 
   5295   /**
   5296    * The username string.
   5297    * Used only if username type is standard or extended, always NULL otherwise.
   5298    * If extended notation is used, this string is pct-decoded string
   5299    * with charset and language tag removed (i.e. it is original username
   5300    * extracted from the extended notation).
   5301    * When userhash is used by the client, this member is NULL and
   5302    * @a userhash_hex and @a userhash_bin are set.
   5303    * The buffer pointed by the @a username becomes invalid when the pointer
   5304    * to the structure is freed by #MHD_free().
   5305    */
   5306   char *username;
   5307 
   5308   /**
   5309    * The length of the @a username.
   5310    * When the @a username is NULL, this member is always zero.
   5311    */
   5312   size_t username_len;
   5313 
   5314   /**
   5315    * The userhash string.
   5316    * Valid only if username type is userhash.
   5317    * This is unqoted string without decoding of the hexadecimal
   5318    * digits (as provided by the client).
   5319    * The buffer pointed by the @a userhash_hex becomes invalid when the pointer
   5320    * to the structure is freed by #MHD_free().
   5321    * @sa #MHD_digest_auth_calc_userhash_hex()
   5322    */
   5323   char *userhash_hex;
   5324 
   5325   /**
   5326    * The length of the @a userhash_hex in characters.
   5327    * The valid size should be #MHD_digest_get_hash_size(algo3) * 2 characters.
   5328    * When the @a userhash_hex is NULL, this member is always zero.
   5329    */
   5330   size_t userhash_hex_len;
   5331 
   5332   /**
   5333    * The userhash decoded to binary form.
   5334    * Used only if username type is userhash, always NULL otherwise.
   5335    * When not NULL, this points to binary sequence @a userhash_hex_len /2 bytes
   5336    * long.
   5337    * The valid size should be #MHD_digest_get_hash_size(algo3) bytes.
   5338    * The buffer pointed by the @a userhash_bin becomes invalid when the pointer
   5339    * to the structure is freed by #MHD_free().
   5340    * @warning This is a binary data, no zero termination.
   5341    * @warning To avoid buffer overruns, always check the size of the data before
   5342    *          use, because @a userhash_bin can point even to zero-sized
   5343    *          data.
   5344    * @sa #MHD_digest_auth_calc_userhash()
   5345    */
   5346   uint8_t *userhash_bin;
   5347 
   5348   /**
   5349    * The 'opaque' parameter value, as specified by client.
   5350    * NULL if not specified by client.
   5351    * The buffer pointed by the @a opaque becomes invalid when the pointer
   5352    * to the structure is freed by #MHD_free().
   5353    */
   5354   char *opaque;
   5355 
   5356   /**
   5357    * The length of the @a opaque.
   5358    * When the @a opaque is NULL, this member is always zero.
   5359    */
   5360   size_t opaque_len;
   5361 
   5362   /**
   5363    * The 'realm' parameter value, as specified by client.
   5364    * NULL if not specified by client.
   5365    * The buffer pointed by the @a realm becomes invalid when the pointer
   5366    * to the structure is freed by #MHD_free().
   5367    */
   5368   char *realm;
   5369 
   5370   /**
   5371    * The length of the @a realm.
   5372    * When the @a realm is NULL, this member is always zero.
   5373    */
   5374   size_t realm_len;
   5375 
   5376   /**
   5377    * The 'qop' parameter value.
   5378    */
   5379   enum MHD_DigestAuthQOP qop;
   5380 
   5381   /**
   5382    * The length of the 'cnonce' parameter value, including possible
   5383    * backslash-escape characters.
   5384    * 'cnonce' is used in hash calculation, which is CPU-intensive procedure.
   5385    * An application may want to reject too large cnonces to limit the CPU load.
   5386    * A few kilobytes is a reasonable limit, typically cnonce is just 32-160
   5387    * characters long.
   5388    */
   5389   size_t cnonce_len;
   5390 
   5391   /**
   5392    * The nc parameter value.
   5393    * Can be used by application to limit the number of nonce re-uses. If @a nc
   5394    * is higher than application wants to allow, then "auth required" response
   5395    * with 'stale=true' could be used to force client to retry with the fresh
   5396    * 'nonce'.
   5397    * If not specified by client or does not have hexadecimal digits only, the
   5398    * value is #MHD_DIGEST_AUTH_INVALID_NC_VALUE.
   5399    */
   5400   uint32_t nc;
   5401 };
   5402 
   5403 
   5404 /**
   5405  * Get information about Digest Authorization client's header.
   5406  *
   5407  * @param connection The MHD connection structure
   5408  * @return NULL if no valid Digest Authorization header is used in the request;
   5409  *         a pointer to the structure with information if the valid request
   5410  *         header found, free using #MHD_free().
   5411  * @sa #MHD_digest_auth_get_username3()
   5412  * @note Available since #MHD_VERSION 0x00097701
   5413  * @ingroup authentication
   5414  */
   5415 _MHD_EXTERN struct MHD_DigestAuthInfo *
   5416 MHD_digest_auth_get_request_info3 (struct MHD_Connection *connection);
   5417 
   5418 
   5419 /**
   5420  * Information from Digest Authorization client's header.
   5421  *
   5422  * All buffers pointed by any struct members are freed when #MHD_free() is
   5423  * called for pointer to this structure.
   5424  *
   5425  * Application may modify buffers as needed until #MHD_free() is called for
   5426  * pointer to this structure
   5427  * @note Available since #MHD_VERSION 0x00097701
   5428  */
   5429 struct MHD_DigestAuthUsernameInfo
   5430 {
   5431   /**
   5432    * The algorithm as defined by client.
   5433    * Set automatically to MD5 if not specified by client.
   5434    * @warning Do not be confused with #MHD_DigestAuthAlgorithm,
   5435    *          which uses other values!
   5436    */
   5437   enum MHD_DigestAuthAlgo3 algo3;
   5438 
   5439   /**
   5440    * The type of username used by client.
   5441    * The 'invalid' and 'missing' types are not used in this structure,
   5442    * instead NULL is returned by #MHD_digest_auth_get_username3().
   5443    */
   5444   enum MHD_DigestAuthUsernameType uname_type;
   5445 
   5446   /**
   5447    * The username string.
   5448    * Used only if username type is standard or extended, always NULL otherwise.
   5449    * If extended notation is used, this string is pct-decoded string
   5450    * with charset and language tag removed (i.e. it is original username
   5451    * extracted from the extended notation).
   5452    * When userhash is used by the client, this member is NULL and
   5453    * @a userhash_hex and @a userhash_bin are set.
   5454    * The buffer pointed by the @a username becomes invalid when the pointer
   5455    * to the structure is freed by #MHD_free().
   5456    */
   5457   char *username;
   5458 
   5459   /**
   5460    * The length of the @a username.
   5461    * When the @a username is NULL, this member is always zero.
   5462    */
   5463   size_t username_len;
   5464 
   5465   /**
   5466    * The userhash string.
   5467    * Valid only if username type is userhash.
   5468    * This is unqoted string without decoding of the hexadecimal
   5469    * digits (as provided by the client).
   5470    * The buffer pointed by the @a userhash_hex becomes invalid when the pointer
   5471    * to the structure is freed by #MHD_free().
   5472    * @sa #MHD_digest_auth_calc_userhash_hex()
   5473    */
   5474   char *userhash_hex;
   5475 
   5476   /**
   5477    * The length of the @a userhash_hex in characters.
   5478    * The valid size should be #MHD_digest_get_hash_size(algo3) * 2 characters.
   5479    * When the @a userhash_hex is NULL, this member is always zero.
   5480    */
   5481   size_t userhash_hex_len;
   5482 
   5483   /**
   5484    * The userhash decoded to binary form.
   5485    * Used only if username type is userhash, always NULL otherwise.
   5486    * When not NULL, this points to binary sequence @a userhash_hex_len /2 bytes
   5487    * long.
   5488    * The valid size should be #MHD_digest_get_hash_size(algo3) bytes.
   5489    * The buffer pointed by the @a userhash_bin becomes invalid when the pointer
   5490    * to the structure is freed by #MHD_free().
   5491    * @warning This is a binary data, no zero termination.
   5492    * @warning To avoid buffer overruns, always check the size of the data before
   5493    *          use, because @a userhash_bin can point even to zero-sized
   5494    *          data.
   5495    * @sa #MHD_digest_auth_calc_userhash()
   5496    */
   5497   uint8_t *userhash_bin;
   5498 };
   5499 
   5500 
   5501 /**
   5502  * Get the username from Digest Authorization client's header.
   5503  *
   5504  * @param connection The MHD connection structure
   5505  * @return NULL if no valid Digest Authorization header is used in the request,
   5506  *         or no username parameter is present in the header, or username is
   5507  *         provided incorrectly by client (see description for
   5508  *         #MHD_DIGEST_AUTH_UNAME_TYPE_INVALID);
   5509  *         a pointer structure with information if the valid request header
   5510  *         found, free using #MHD_free().
   5511  * @sa #MHD_digest_auth_get_request_info3() provides more complete information
   5512  * @note Available since #MHD_VERSION 0x00097701
   5513  * @ingroup authentication
   5514  */
   5515 _MHD_EXTERN struct MHD_DigestAuthUsernameInfo *
   5516 MHD_digest_auth_get_username3 (struct MHD_Connection *connection);
   5517 
   5518 
   5519 /**
   5520  * The result of digest authentication of the client.
   5521  *
   5522  * All error values are zero or negative.
   5523  *
   5524  * @note Available since #MHD_VERSION 0x00097701
   5525  */
   5526 enum MHD_DigestAuthResult
   5527 {
   5528   /**
   5529    * Authentication OK.
   5530    */
   5531   MHD_DAUTH_OK = 1,
   5532 
   5533   /**
   5534    * General error, like "out of memory".
   5535    */
   5536   MHD_DAUTH_ERROR = 0,
   5537 
   5538   /**
   5539    * No "Authorization" header or wrong format of the header.
   5540    * Also may be returned if required parameters in client Authorisation header
   5541    * are missing or broken (in invalid format).
   5542    */
   5543   MHD_DAUTH_WRONG_HEADER = -1,
   5544 
   5545   /**
   5546    * Wrong 'username'.
   5547    */
   5548   MHD_DAUTH_WRONG_USERNAME = -2,
   5549 
   5550   /**
   5551    * Wrong 'realm'.
   5552    */
   5553   MHD_DAUTH_WRONG_REALM = -3,
   5554 
   5555   /**
   5556    * Wrong 'URI' (or URI parameters).
   5557    */
   5558   MHD_DAUTH_WRONG_URI = -4,
   5559 
   5560   /**
   5561    * Wrong 'qop'.
   5562    */
   5563   MHD_DAUTH_WRONG_QOP = -5,
   5564 
   5565   /**
   5566    * Wrong 'algorithm'.
   5567    */
   5568   MHD_DAUTH_WRONG_ALGO = -6,
   5569 
   5570   /**
   5571    * Too large (>64 KiB) Authorization parameter value.
   5572    */
   5573   MHD_DAUTH_TOO_LARGE = -15,
   5574 
   5575   /* The different form of naming is intentionally used for the results below,
   5576    * as they are more important */
   5577 
   5578   /**
   5579    * The 'nonce' is too old. Suggest the client to retry with the same
   5580    * username and password to get the fresh 'nonce'.
   5581    * The validity of the 'nonce' may be not checked.
   5582    */
   5583   MHD_DAUTH_NONCE_STALE = -17,
   5584 
   5585   /**
   5586    * The 'nonce' was generated by MHD for other conditions.
   5587    * This value is only returned if #MHD_OPTION_DIGEST_AUTH_NONCE_BIND_TYPE
   5588    * is set to anything other than #MHD_DAUTH_BIND_NONCE_NONE.
   5589    * The interpretation of this code could be different. For example, if
   5590    * #MHD_DAUTH_BIND_NONCE_URI is set and client just used the same 'nonce' for
   5591    * another URI, the code could be handled as #MHD_DAUTH_NONCE_STALE as
   5592    * RFCs allow nonces re-using for other URIs in the same "protection
   5593    * space". However, if only #MHD_DAUTH_BIND_NONCE_CLIENT_IP bit is set and
   5594    * it is know that clients have fixed IP addresses, this return code could
   5595    * be handled like #MHD_DAUTH_NONCE_WRONG.
   5596    */
   5597   MHD_DAUTH_NONCE_OTHER_COND = -18,
   5598 
   5599   /**
   5600    * The 'nonce' is wrong. May indicate an attack attempt.
   5601    */
   5602   MHD_DAUTH_NONCE_WRONG = -33,
   5603 
   5604   /**
   5605    * The 'response' is wrong. Typically it means that wrong password used.
   5606    * May indicate an attack attempt.
   5607    */
   5608   MHD_DAUTH_RESPONSE_WRONG = -34
   5609 };
   5610 
   5611 
   5612 /**
   5613  * Authenticates the authorization header sent by the client.
   5614  *
   5615  * If RFC2069 mode is allowed by setting bit #MHD_DIGEST_AUTH_QOP_NONE in
   5616  * @a mqop and the client uses this mode, then server generated nonces are
   5617  * used as one-time nonces because nonce-count is not supported in this old RFC.
   5618  * Communication in this mode is very inefficient, especially if the client
   5619  * requests several resources one-by-one as for every request a new nonce must
   5620  * be generated and client repeats all requests twice (first time to get a new
   5621  * nonce and second time to perform an authorised request).
   5622  *
   5623  * @param connection the MHD connection structure
   5624  * @param realm the realm for authorization of the client
   5625  * @param username the username to be authenticated, must be in clear text
   5626  *                 even if userhash is used by the client
   5627  * @param password the password matching the @a username (and the @a realm)
   5628  * @param nonce_timeout the period of seconds since nonce generation, when
   5629  *                      the nonce is recognised as valid and not stale;
   5630  *                      if zero is specified then daemon default value is used.
   5631  * @param max_nc the maximum allowed nc (Nonce Count) value, if client's nc
   5632  *               exceeds the specified value then MHD_DAUTH_NONCE_STALE is
   5633  *               returned;
   5634  *               if zero is specified then daemon default value is used.
   5635  * @param mqop the QOP to use
   5636  * @param malgo3 digest algorithms allowed to use, fail if algorithm used
   5637  *               by the client is not allowed by this parameter
   5638  * @return #MHD_DAUTH_OK if authenticated,
   5639  *         the error code otherwise
   5640  * @note Available since #MHD_VERSION 0x00097708
   5641  * @ingroup authentication
   5642  */
   5643 _MHD_EXTERN enum MHD_DigestAuthResult
   5644 MHD_digest_auth_check3 (struct MHD_Connection *connection,
   5645                         const char *realm,
   5646                         const char *username,
   5647                         const char *password,
   5648                         unsigned int nonce_timeout,
   5649                         uint32_t max_nc,
   5650                         enum MHD_DigestAuthMultiQOP mqop,
   5651                         enum MHD_DigestAuthMultiAlgo3 malgo3);
   5652 
   5653 
   5654 /**
   5655  * Calculate userdigest, return it as a binary data.
   5656  *
   5657  * The "userdigest" is the hash of the "username:realm:password" string.
   5658  *
   5659  * The "userdigest" can be used to avoid storing the password in clear text
   5660  * in database/files
   5661  *
   5662  * This function is designed to improve security of stored credentials,
   5663  * the "userdigest" does not improve security of the authentication process.
   5664  *
   5665  * The results can be used to store username & userdigest pairs instead of
   5666  * username & password pairs. To further improve security, application may
   5667  * store username & userhash & userdigest triplets.
   5668  *
   5669  * @param algo3 the digest algorithm
   5670  * @param username the username
   5671  * @param realm the realm
   5672  * @param password the password
   5673  * @param[out] userdigest_bin the output buffer for userdigest;
   5674  *                            if this function succeeds, then this buffer has
   5675  *                            #MHD_digest_get_hash_size(algo3) bytes of
   5676  *                            userdigest upon return
   5677  * @param bin_buf_size the size of the @a userdigest_bin buffer, must be
   5678  *                     at least #MHD_digest_get_hash_size(algo3) bytes long
   5679  * @return MHD_YES on success,
   5680  *         MHD_NO if @a userdigest_bin is too small or if @a algo3 algorithm is
   5681  *         not supported (or external error has occurred,
   5682  *         see #MHD_FEATURE_EXTERN_HASH).
   5683  * @sa #MHD_digest_auth_check_digest3()
   5684  * @note Available since #MHD_VERSION 0x00097701
   5685  * @ingroup authentication
   5686  */
   5687 _MHD_EXTERN enum MHD_Result
   5688 MHD_digest_auth_calc_userdigest (enum MHD_DigestAuthAlgo3 algo3,
   5689                                  const char *username,
   5690                                  const char *realm,
   5691                                  const char *password,
   5692                                  void *userdigest_bin,
   5693                                  size_t bin_buf_size);
   5694 
   5695 
   5696 /**
   5697  * Authenticates the authorization header sent by the client by using
   5698  * hash of "username:realm:password".
   5699  *
   5700  * If RFC2069 mode is allowed by setting bit #MHD_DIGEST_AUTH_QOP_NONE in
   5701  * @a mqop and the client uses this mode, then server generated nonces are
   5702  * used as one-time nonces because nonce-count is not supported in this old RFC.
   5703  * Communication in this mode is very inefficient, especially if the client
   5704  * requests several resources one-by-one as for every request a new nonce must
   5705  * be generated and client repeats all requests twice (first time to get a new
   5706  * nonce and second time to perform an authorised request).
   5707  *
   5708  * @param connection the MHD connection structure
   5709  * @param realm the realm for authorization of the client
   5710  * @param username the username to be authenticated, must be in clear text
   5711  *                 even if userhash is used by the client
   5712  * @param userdigest the precalculated binary hash of the string
   5713  *                   "username:realm:password",
   5714  *                   see #MHD_digest_auth_calc_userdigest()
   5715  * @param userdigest_size the size of the @a userdigest in bytes, must match the
   5716  *                        hashing algorithm (see #MHD_MD5_DIGEST_SIZE,
   5717  *                        #MHD_SHA256_DIGEST_SIZE, #MHD_SHA512_256_DIGEST_SIZE,
   5718  *                        #MHD_digest_get_hash_size())
   5719  * @param nonce_timeout the period of seconds since nonce generation, when
   5720  *                      the nonce is recognised as valid and not stale;
   5721  *                      if zero is specified then daemon default value is used.
   5722  * @param max_nc the maximum allowed nc (Nonce Count) value, if client's nc
   5723  *               exceeds the specified value then MHD_DAUTH_NONCE_STALE is
   5724  *               returned;
   5725  *               if zero is specified then daemon default value is used.
   5726  * @param mqop the QOP to use
   5727  * @param malgo3 digest algorithms allowed to use, fail if algorithm used
   5728  *               by the client is not allowed by this parameter;
   5729  *               more than one base algorithms (MD5, SHA-256, SHA-512/256)
   5730  *               cannot be used at the same time for this function
   5731  *               as @a userdigest must match specified algorithm
   5732  * @return #MHD_DAUTH_OK if authenticated,
   5733  *         the error code otherwise
   5734  * @sa #MHD_digest_auth_calc_userdigest()
   5735  * @note Available since #MHD_VERSION 0x00097701
   5736  * @ingroup authentication
   5737  */
   5738 _MHD_EXTERN enum MHD_DigestAuthResult
   5739 MHD_digest_auth_check_digest3 (struct MHD_Connection *connection,
   5740                                const char *realm,
   5741                                const char *username,
   5742                                const void *userdigest,
   5743                                size_t userdigest_size,
   5744                                unsigned int nonce_timeout,
   5745                                uint32_t max_nc,
   5746                                enum MHD_DigestAuthMultiQOP mqop,
   5747                                enum MHD_DigestAuthMultiAlgo3 malgo3);
   5748 
   5749 
   5750 /**
   5751  * Queues a response to request authentication from the client
   5752  *
   5753  * This function modifies provided @a response. The @a response must not be
   5754  * reused and should be destroyed (by #MHD_destroy_response()) after call of
   5755  * this function.
   5756  *
   5757  * If @a mqop allows both RFC 2069 (MHD_DIGEST_AUTH_QOP_NONE) and QOP with
   5758  * value, then response is formed like if MHD_DIGEST_AUTH_QOP_NONE bit was
   5759  * not set, because such response should be backward-compatible with RFC 2069.
   5760  *
   5761  * If @a mqop allows only MHD_DIGEST_AUTH_MULT_QOP_NONE, then the response is
   5762  * formed in strict accordance with RFC 2069 (no 'qop', no 'userhash', no
   5763  * 'charset'). For better compatibility with clients, it is recommended (but
   5764  * not required) to set @a domain to NULL in this mode.
   5765  *
   5766  * @param connection the MHD connection structure
   5767  * @param realm the realm presented to the client
   5768  * @param opaque the string for opaque value, can be NULL, but NULL is
   5769  *               not recommended for better compatibility with clients;
   5770  *               the recommended format is hex or Base64 encoded string
   5771  * @param domain the optional space-separated list of URIs for which the
   5772  *               same authorisation could be used, URIs can be in form
   5773  *               "path-absolute" (the path for the same host with initial slash)
   5774  *               or in form "absolute-URI" (the full path with protocol), in
   5775  *               any case client may assume that URI is in the same "protection
   5776  *               space" if it starts with any of values specified here;
   5777  *               could be NULL (clients typically assume that the same
   5778  *               credentials could be used for any URI on the same host);
   5779  *               this list provides information for the client only and does
   5780  *               not actually restrict anything on the server side
   5781  * @param response the reply to send; should contain the "access denied"
   5782  *                 body;
   5783  *                 note: this function sets the "WWW Authenticate" header and
   5784  *                 the caller should not set this header;
   5785  *                 the NULL is tolerated
   5786  * @param signal_stale if set to #MHD_YES then indication of stale nonce used in
   5787  *                     the client's request is signalled by adding 'stale=true'
   5788  *                     to the authentication header, this instructs the client
   5789  *                     to retry immediately with the new nonce and the same
   5790  *                     credentials, without asking user for the new password
   5791  * @param mqop the QOP to use
   5792  * @param malgo3 digest algorithm to use; if several algorithms are allowed
   5793  *               then MD5 is preferred (currently, may be changed in next
   5794  *               versions)
   5795  * @param userhash_support if set to non-zero value (#MHD_YES) then support of
   5796  *                         userhash is indicated, allowing client to provide
   5797  *                         hash("username:realm") instead of the username in
   5798  *                         clear text;
   5799  *                         note that clients are allowed to provide the username
   5800  *                         in cleartext even if this parameter set to non-zero;
   5801  *                         when userhash is used, application must be ready to
   5802  *                         identify users by provided userhash value instead of
   5803  *                         username; see #MHD_digest_auth_calc_userhash() and
   5804  *                         #MHD_digest_auth_calc_userhash_hex()
   5805  * @param prefer_utf8 if not set to #MHD_NO, parameter 'charset=UTF-8' is
   5806  *                    added, indicating for the client that UTF-8 encoding for
   5807  *                    the username is preferred
   5808  * @return #MHD_YES on success, #MHD_NO otherwise
   5809  * @note Available since #MHD_VERSION 0x00097701
   5810  * @ingroup authentication
   5811  */
   5812 _MHD_EXTERN enum MHD_Result
   5813 MHD_queue_auth_required_response3 (struct MHD_Connection *connection,
   5814                                    const char *realm,
   5815                                    const char *opaque,
   5816                                    const char *domain,
   5817                                    struct MHD_Response *response,
   5818                                    int signal_stale,
   5819                                    enum MHD_DigestAuthMultiQOP mqop,
   5820                                    enum MHD_DigestAuthMultiAlgo3 algo,
   5821                                    int userhash_support,
   5822                                    int prefer_utf8);
   5823 
   5824 
   5825 /**
   5826  * Constant to indicate that the nonce of the provided
   5827  * authentication code was wrong.
   5828  * Used as return code by #MHD_digest_auth_check(), #MHD_digest_auth_check2(),
   5829  * #MHD_digest_auth_check_digest(), #MHD_digest_auth_check_digest2().
   5830  * @ingroup authentication
   5831  */
   5832 #define MHD_INVALID_NONCE -1
   5833 
   5834 
   5835 /**
   5836  * Get the username from the authorization header sent by the client
   5837  *
   5838  * This function supports username in standard and extended notations.
   5839  * "userhash" is not supported by this function.
   5840  *
   5841  * @param connection The MHD connection structure
   5842  * @return NULL if no username could be found, username provided as
   5843  *         "userhash", extended notation broken or memory allocation error
   5844  *         occurs;
   5845  *         a pointer to the username if found, free using #MHD_free().
   5846  * @warning Returned value must be freed by #MHD_free().
   5847  * @sa #MHD_digest_auth_get_username3()
   5848  * @ingroup authentication
   5849  */
   5850 _MHD_EXTERN char *
   5851 MHD_digest_auth_get_username (struct MHD_Connection *connection);
   5852 
   5853 
   5854 /**
   5855  * Which digest algorithm should MHD use for HTTP digest authentication?
   5856  * Used as parameter for #MHD_digest_auth_check2(),
   5857  * #MHD_digest_auth_check_digest2(), #MHD_queue_auth_fail_response2().
   5858  */
   5859 enum MHD_DigestAuthAlgorithm
   5860 {
   5861 
   5862   /**
   5863    * MHD should pick (currently defaults to MD5).
   5864    */
   5865   MHD_DIGEST_ALG_AUTO = 0,
   5866 
   5867   /**
   5868    * Force use of MD5.
   5869    */
   5870   MHD_DIGEST_ALG_MD5,
   5871 
   5872   /**
   5873    * Force use of SHA-256.
   5874    */
   5875   MHD_DIGEST_ALG_SHA256
   5876 
   5877 } _MHD_FIXED_ENUM;
   5878 
   5879 
   5880 /**
   5881  * Authenticates the authorization header sent by the client.
   5882  *
   5883  * @param connection The MHD connection structure
   5884  * @param realm The realm presented to the client
   5885  * @param username The username needs to be authenticated
   5886  * @param password The password used in the authentication
   5887  * @param nonce_timeout The amount of time for a nonce to be
   5888  *      invalid in seconds
   5889  * @param algo digest algorithms allowed for verification
   5890  * @return #MHD_YES if authenticated, #MHD_NO if not,
   5891  *         #MHD_INVALID_NONCE if nonce is invalid or stale
   5892  * @note Available since #MHD_VERSION 0x00096200
   5893  * @deprecated use MHD_digest_auth_check3()
   5894  * @ingroup authentication
   5895  */
   5896 _MHD_EXTERN int
   5897 MHD_digest_auth_check2 (struct MHD_Connection *connection,
   5898                         const char *realm,
   5899                         const char *username,
   5900                         const char *password,
   5901                         unsigned int nonce_timeout,
   5902                         enum MHD_DigestAuthAlgorithm algo);
   5903 
   5904 
   5905 /**
   5906  * Authenticates the authorization header sent by the client.
   5907  * Uses #MHD_DIGEST_ALG_MD5 (for now, for backwards-compatibility).
   5908  * Note that this MAY change to #MHD_DIGEST_ALG_AUTO in the future.
   5909  * If you want to be sure you get MD5, use #MHD_digest_auth_check2()
   5910  * and specify MD5 explicitly.
   5911  *
   5912  * @param connection The MHD connection structure
   5913  * @param realm The realm presented to the client
   5914  * @param username The username needs to be authenticated
   5915  * @param password The password used in the authentication
   5916  * @param nonce_timeout The amount of time for a nonce to be
   5917  *      invalid in seconds
   5918  * @return #MHD_YES if authenticated, #MHD_NO if not,
   5919  *         #MHD_INVALID_NONCE if nonce is invalid or stale
   5920  * @deprecated use MHD_digest_auth_check3()
   5921  * @ingroup authentication
   5922  */
   5923 _MHD_EXTERN int
   5924 MHD_digest_auth_check (struct MHD_Connection *connection,
   5925                        const char *realm,
   5926                        const char *username,
   5927                        const char *password,
   5928                        unsigned int nonce_timeout);
   5929 
   5930 
   5931 /**
   5932  * Authenticates the authorization header sent by the client.
   5933  *
   5934  * @param connection The MHD connection structure
   5935  * @param realm The realm presented to the client
   5936  * @param username The username needs to be authenticated
   5937  * @param digest An `unsigned char *' pointer to the binary MD5 sum
   5938  *      for the precalculated hash value "username:realm:password"
   5939  *      of @a digest_size bytes
   5940  * @param digest_size number of bytes in @a digest (size must match @a algo!)
   5941  * @param nonce_timeout The amount of time for a nonce to be
   5942  *      invalid in seconds
   5943  * @param algo digest algorithm allowed for verification; exactly one
   5944  *      algorithm must be named, as @a digest is a hash produced by one
   5945  *      specific algorithm.  #MHD_DIGEST_ALG_AUTO cannot be used here
   5946  *      and makes this function return #MHD_NO
   5947  * @return #MHD_YES if authenticated, #MHD_NO if not,
   5948  *         #MHD_INVALID_NONCE if nonce is invalid or stale
   5949  * @note Available since #MHD_VERSION 0x00096200
   5950  * @deprecated use MHD_digest_auth_check_digest3()
   5951  * @ingroup authentication
   5952  */
   5953 _MHD_EXTERN int
   5954 MHD_digest_auth_check_digest2 (struct MHD_Connection *connection,
   5955                                const char *realm,
   5956                                const char *username,
   5957                                const uint8_t *digest,
   5958                                size_t digest_size,
   5959                                unsigned int nonce_timeout,
   5960                                enum MHD_DigestAuthAlgorithm algo);
   5961 
   5962 
   5963 /**
   5964  * Authenticates the authorization header sent by the client
   5965  * Uses #MHD_DIGEST_ALG_MD5 (required, as @a digest is of fixed
   5966  * size).
   5967  *
   5968  * @param connection The MHD connection structure
   5969  * @param realm The realm presented to the client
   5970  * @param username The username needs to be authenticated
   5971  * @param digest An `unsigned char *' pointer to the binary hash
   5972  *    for the precalculated hash value "username:realm:password";
   5973  *    length must be #MHD_MD5_DIGEST_SIZE bytes
   5974  * @param nonce_timeout The amount of time for a nonce to be
   5975  *      invalid in seconds
   5976  * @return #MHD_YES if authenticated, #MHD_NO if not,
   5977  *         #MHD_INVALID_NONCE if nonce is invalid or stale
   5978  * @note Available since #MHD_VERSION 0x00096000
   5979  * @deprecated use #MHD_digest_auth_check_digest3()
   5980  * @ingroup authentication
   5981  */
   5982 _MHD_EXTERN int
   5983 MHD_digest_auth_check_digest (struct MHD_Connection *connection,
   5984                               const char *realm,
   5985                               const char *username,
   5986                               const uint8_t digest[MHD_MD5_DIGEST_SIZE],
   5987                               unsigned int nonce_timeout);
   5988 
   5989 
   5990 /**
   5991  * Queues a response to request authentication from the client
   5992  *
   5993  * This function modifies provided @a response. The @a response must not be
   5994  * reused and should be destroyed after call of this function.
   5995  *
   5996  * @param connection The MHD connection structure
   5997  * @param realm the realm presented to the client
   5998  * @param opaque string to user for opaque value
   5999  * @param response reply to send; should contain the "access denied"
   6000  *        body; note that this function will set the "WWW Authenticate"
   6001  *        header and that the caller should not do this; the NULL is tolerated
   6002  * @param signal_stale #MHD_YES if the nonce is stale to add
   6003  *        'stale=true' to the authentication header
   6004  * @param algo digest algorithm to use
   6005  * @return #MHD_YES on success, #MHD_NO otherwise
   6006  * @note Available since #MHD_VERSION 0x00096200
   6007  * @deprecated use MHD_queue_auth_required_response3()
   6008  * @ingroup authentication
   6009  */
   6010 _MHD_EXTERN enum MHD_Result
   6011 MHD_queue_auth_fail_response2 (struct MHD_Connection *connection,
   6012                                const char *realm,
   6013                                const char *opaque,
   6014                                struct MHD_Response *response,
   6015                                int signal_stale,
   6016                                enum MHD_DigestAuthAlgorithm algo);
   6017 
   6018 
   6019 /**
   6020  * Queues a response to request authentication from the client.
   6021  * For now uses MD5 (for backwards-compatibility). Still, if you
   6022  * need to be sure, use #MHD_queue_auth_fail_response2().
   6023  *
   6024  * This function modifies provided @a response. The @a response must not be
   6025  * reused and should be destroyed after call of this function.
   6026  *
   6027  * @param connection The MHD connection structure
   6028  * @param realm the realm presented to the client
   6029  * @param opaque string to user for opaque value
   6030  * @param response reply to send; should contain the "access denied"
   6031  *        body; note that this function will set the "WWW Authenticate"
   6032  *        header and that the caller should not do this; the NULL is tolerated
   6033  * @param signal_stale #MHD_YES if the nonce is stale to add
   6034  *        'stale=true' to the authentication header
   6035  * @return #MHD_YES on success, #MHD_NO otherwise
   6036  * @deprecated use MHD_queue_auth_required_response3()
   6037  * @ingroup authentication
   6038  */
   6039 _MHD_EXTERN enum MHD_Result
   6040 MHD_queue_auth_fail_response (struct MHD_Connection *connection,
   6041                               const char *realm,
   6042                               const char *opaque,
   6043                               struct MHD_Response *response,
   6044                               int signal_stale);
   6045 
   6046 
   6047 /* ********************* Basic Authentication functions *************** */
   6048 
   6049 
   6050 /**
   6051  * Information decoded from Basic Authentication client's header.
   6052  *
   6053  * The username and the password are technically allowed to have binary zeros,
   6054  * username_len and password_len could be used to detect such situations.
   6055  *
   6056  * The buffers pointed by username and password members are freed
   6057  * when #MHD_free() is called for pointer to this structure.
   6058  *
   6059  * Application may modify buffers as needed until #MHD_free() is called for
   6060  * pointer to this structure
   6061  */
   6062 struct MHD_BasicAuthInfo
   6063 {
   6064   /**
   6065    * The username, cannot be NULL.
   6066    * The buffer pointed by the @a username becomes invalid when the pointer
   6067    * to the structure is freed by #MHD_free().
   6068    */
   6069   char *username;
   6070 
   6071   /**
   6072    * The length of the @a username, not including zero-termination
   6073    */
   6074   size_t username_len;
   6075 
   6076   /**
   6077    * The password, may be NULL if password is not encoded by the client.
   6078    * The buffer pointed by the @a password becomes invalid when the pointer
   6079    * to the structure is freed by #MHD_free().
   6080    */
   6081   char *password;
   6082 
   6083   /**
   6084    * The length of the @a password, not including zero-termination;
   6085    * when the @a password is NULL, the length is always zero.
   6086    */
   6087   size_t password_len;
   6088 };
   6089 
   6090 /**
   6091  * Get the username and password from the Basic Authorisation header
   6092  * sent by the client
   6093  *
   6094  * @param connection the MHD connection structure
   6095  * @return NULL if no valid Basic Authentication header is present in
   6096  *         current request, or
   6097  *         pointer to structure with username and password, which must be
   6098  *         freed by #MHD_free().
   6099  * @note Available since #MHD_VERSION 0x00097701
   6100  * @ingroup authentication
   6101  */
   6102 _MHD_EXTERN struct MHD_BasicAuthInfo *
   6103 MHD_basic_auth_get_username_password3 (struct MHD_Connection *connection);
   6104 
   6105 /**
   6106  * Queues a response to request basic authentication from the client.
   6107  *
   6108  * The given response object is expected to include the payload for
   6109  * the response; the "WWW-Authenticate" header will be added and the
   6110  * response queued with the 'UNAUTHORIZED' status code.
   6111  *
   6112  * See RFC 7617#section-2 for details.
   6113  *
   6114  * The @a response is modified by this function. The modified response object
   6115  * can be used to respond subsequent requests by #MHD_queue_response()
   6116  * function with status code #MHD_HTTP_UNAUTHORIZED and must not be used again
   6117  * with MHD_queue_basic_auth_required_response3() function. The response could
   6118  * be destroyed right after call of this function.
   6119  *
   6120  * @param connection the MHD connection structure
   6121  * @param realm the realm presented to the client
   6122  * @param prefer_utf8 if not set to #MHD_NO, parameter'charset="UTF-8"' will
   6123  *                    be added, indicating for client that UTF-8 encoding
   6124  *                    is preferred
   6125  * @param response the response object to modify and queue; the NULL
   6126  *                 is tolerated
   6127  * @return #MHD_YES on success, #MHD_NO otherwise
   6128  * @note Available since #MHD_VERSION 0x00097704
   6129  * @ingroup authentication
   6130  */
   6131 _MHD_EXTERN enum MHD_Result
   6132 MHD_queue_basic_auth_required_response3 (struct MHD_Connection *connection,
   6133                                          const char *realm,
   6134                                          int prefer_utf8,
   6135                                          struct MHD_Response *response);
   6136 
   6137 /**
   6138  * Get the username and password from the basic authorization header sent by the client
   6139  *
   6140  * @param connection The MHD connection structure
   6141  * @param[out] password a pointer for the password, free using #MHD_free().
   6142  * @return NULL if no username could be found, a pointer
   6143  *      to the username if found, free using #MHD_free().
   6144  * @deprecated use #MHD_basic_auth_get_username_password3()
   6145  * @ingroup authentication
   6146  */
   6147 _MHD_EXTERN char *
   6148 MHD_basic_auth_get_username_password (struct MHD_Connection *connection,
   6149                                       char **password);
   6150 
   6151 
   6152 /**
   6153  * Queues a response to request basic authentication from the client
   6154  * The given response object is expected to include the payload for
   6155  * the response; the "WWW-Authenticate" header will be added and the
   6156  * response queued with the 'UNAUTHORIZED' status code.
   6157  *
   6158  * @param connection The MHD connection structure
   6159  * @param realm the realm presented to the client
   6160  * @param response response object to modify and queue; the NULL is tolerated
   6161  * @return #MHD_YES on success, #MHD_NO otherwise
   6162  * @deprecated use MHD_queue_basic_auth_required_response3()
   6163  * @ingroup authentication
   6164  */
   6165 _MHD_EXTERN enum MHD_Result
   6166 MHD_queue_basic_auth_fail_response (struct MHD_Connection *connection,
   6167                                     const char *realm,
   6168                                     struct MHD_Response *response);
   6169 
   6170 /* ********************** generic query functions ********************** */
   6171 
   6172 
   6173 /**
   6174  * Obtain information about the given connection.
   6175  * The returned pointer is invalidated with the next call of this function or
   6176  * when the connection is closed.
   6177  *
   6178  * @param connection what connection to get information about
   6179  * @param info_type what information is desired?
   6180  * @param ... depends on @a info_type
   6181  * @return NULL if this information is not available
   6182  *         (or if the @a info_type is unknown)
   6183  * @ingroup specialized
   6184  */
   6185 _MHD_EXTERN const union MHD_ConnectionInfo *
   6186 MHD_get_connection_info (struct MHD_Connection *connection,
   6187                          enum MHD_ConnectionInfoType info_type,
   6188                          ...);
   6189 
   6190 
   6191 /**
   6192  * MHD connection options.  Given to #MHD_set_connection_option to
   6193  * set custom options for a particular connection.
   6194  */
   6195 enum MHD_CONNECTION_OPTION
   6196 {
   6197 
   6198   /**
   6199    * Set a custom timeout for the given connection.  Specified
   6200    * as the number of seconds, given as an `unsigned int`.  Use
   6201    * zero for no timeout.
   6202    * If timeout was set to zero (or unset) before, setup of new value by
   6203    * MHD_set_connection_option() will reset timeout timer.
   6204    * Values larger than (UINT64_MAX / 2000 - 1) will
   6205    * be clipped to this number.
   6206    */
   6207   MHD_CONNECTION_OPTION_TIMEOUT
   6208 
   6209 } _MHD_FIXED_ENUM;
   6210 
   6211 
   6212 /**
   6213  * Set a custom option for the given connection, overriding defaults.
   6214  *
   6215  * @param connection connection to modify
   6216  * @param option option to set
   6217  * @param ... arguments to the option, depending on the option type
   6218  * @return #MHD_YES on success, #MHD_NO if setting the option failed
   6219  * @ingroup specialized
   6220  */
   6221 _MHD_EXTERN enum MHD_Result
   6222 MHD_set_connection_option (struct MHD_Connection *connection,
   6223                            enum MHD_CONNECTION_OPTION option,
   6224                            ...);
   6225 
   6226 
   6227 /**
   6228  * Information about an MHD daemon.
   6229  */
   6230 union MHD_DaemonInfo
   6231 {
   6232   /**
   6233    * Size of the key, no longer supported.
   6234    * @deprecated
   6235    */
   6236   size_t key_size;
   6237 
   6238   /**
   6239    * Size of the mac key, no longer supported.
   6240    * @deprecated
   6241    */
   6242   size_t mac_key_size;
   6243 
   6244   /**
   6245    * Socket, returned for #MHD_DAEMON_INFO_LISTEN_FD.
   6246    */
   6247   MHD_socket listen_fd;
   6248 
   6249   /**
   6250    * Bind port number, returned for #MHD_DAEMON_INFO_BIND_PORT.
   6251    */
   6252   uint16_t port;
   6253 
   6254   /**
   6255    * epoll FD, returned for #MHD_DAEMON_INFO_EPOLL_FD.
   6256    */
   6257   int epoll_fd;
   6258 
   6259   /**
   6260    * Number of active connections, for #MHD_DAEMON_INFO_CURRENT_CONNECTIONS.
   6261    */
   6262   unsigned int num_connections;
   6263 
   6264   /**
   6265    * Combination of #MHD_FLAG values, for #MHD_DAEMON_INFO_FLAGS.
   6266    * This value is actually a bitfield.
   6267    * Note: flags may differ from original 'flags' specified for
   6268    * daemon, especially if #MHD_USE_AUTO was set.
   6269    */
   6270   enum MHD_FLAG flags;
   6271 };
   6272 
   6273 
   6274 /**
   6275  * Obtain information about the given daemon.
   6276  * The returned pointer is invalidated with the next call of this function or
   6277  * when the daemon is stopped.
   6278  *
   6279  * @param daemon what daemon to get information about
   6280  * @param info_type what information is desired?
   6281  * @param ... depends on @a info_type
   6282  * @return NULL if this information is not available
   6283  *         (or if the @a info_type is unknown)
   6284  * @ingroup specialized
   6285  */
   6286 _MHD_EXTERN const union MHD_DaemonInfo *
   6287 MHD_get_daemon_info (struct MHD_Daemon *daemon,
   6288                      enum MHD_DaemonInfoType info_type,
   6289                      ...);
   6290 
   6291 
   6292 /**
   6293  * Obtain the version of this library
   6294  *
   6295  * @return static version string, e.g. "0.9.9"
   6296  * @ingroup specialized
   6297  */
   6298 _MHD_EXTERN const char *
   6299 MHD_get_version (void);
   6300 
   6301 
   6302 /**
   6303  * Obtain the version of this library as a binary value.
   6304  *
   6305  * @return version binary value, e.g. "0x00090900" (#MHD_VERSION of
   6306  *         compiled MHD binary)
   6307  * @note Available since #MHD_VERSION 0x00097601
   6308  * @ingroup specialized
   6309  */
   6310 _MHD_EXTERN uint32_t
   6311 MHD_get_version_bin (void);
   6312 
   6313 
   6314 /**
   6315  * Types of information about MHD features,
   6316  * used by #MHD_is_feature_supported().
   6317  */
   6318 enum MHD_FEATURE
   6319 {
   6320   /**
   6321    * Get whether messages are supported. If supported then in debug
   6322    * mode messages can be printed to stderr or to external logger.
   6323    */
   6324   MHD_FEATURE_MESSAGES = 1,
   6325 
   6326   /**
   6327    * Get whether HTTPS is supported.  If supported then flag
   6328    * #MHD_USE_TLS and options #MHD_OPTION_HTTPS_MEM_KEY,
   6329    * #MHD_OPTION_HTTPS_MEM_CERT, #MHD_OPTION_HTTPS_MEM_TRUST,
   6330    * #MHD_OPTION_HTTPS_MEM_DHPARAMS, #MHD_OPTION_HTTPS_CRED_TYPE,
   6331    * #MHD_OPTION_HTTPS_PRIORITIES can be used.
   6332    */
   6333   MHD_FEATURE_TLS = 2,
   6334   MHD_FEATURE_SSL = 2,
   6335 
   6336   /**
   6337    * Get whether option #MHD_OPTION_HTTPS_CERT_CALLBACK is
   6338    * supported.
   6339    */
   6340   MHD_FEATURE_HTTPS_CERT_CALLBACK = 3,
   6341 
   6342   /**
   6343    * Get whether IPv6 is supported. If supported then flag
   6344    * #MHD_USE_IPv6 can be used.
   6345    */
   6346   MHD_FEATURE_IPv6 = 4,
   6347 
   6348   /**
   6349    * Get whether IPv6 without IPv4 is supported. If not supported
   6350    * then IPv4 is always enabled in IPv6 sockets and
   6351    * flag #MHD_USE_DUAL_STACK is always used when #MHD_USE_IPv6 is
   6352    * specified.
   6353    */
   6354   MHD_FEATURE_IPv6_ONLY = 5,
   6355 
   6356   /**
   6357    * Get whether `poll()` is supported. If supported then flag
   6358    * #MHD_USE_POLL can be used.
   6359    */
   6360   MHD_FEATURE_POLL = 6,
   6361 
   6362   /**
   6363    * Get whether `epoll()` is supported. If supported then Flags
   6364    * #MHD_USE_EPOLL and
   6365    * #MHD_USE_EPOLL_INTERNAL_THREAD can be used.
   6366    */
   6367   MHD_FEATURE_EPOLL = 7,
   6368 
   6369   /**
   6370    * Get whether shutdown on listen socket to signal other
   6371    * threads is supported. If not supported flag
   6372    * #MHD_USE_ITC is automatically forced.
   6373    */
   6374   MHD_FEATURE_SHUTDOWN_LISTEN_SOCKET = 8,
   6375 
   6376   /**
   6377    * Get whether socketpair is used internally instead of pipe to
   6378    * signal other threads.
   6379    */
   6380   MHD_FEATURE_SOCKETPAIR = 9,
   6381 
   6382   /**
   6383    * Get whether TCP Fast Open is supported. If supported then
   6384    * flag #MHD_USE_TCP_FASTOPEN and option
   6385    * #MHD_OPTION_TCP_FASTOPEN_QUEUE_SIZE can be used.
   6386    */
   6387   MHD_FEATURE_TCP_FASTOPEN = 10,
   6388 
   6389   /**
   6390    * Get whether HTTP Basic authorization is supported. If supported
   6391    * then functions #MHD_basic_auth_get_username_password and
   6392    * #MHD_queue_basic_auth_fail_response can be used.
   6393    */
   6394   MHD_FEATURE_BASIC_AUTH = 11,
   6395 
   6396   /**
   6397    * Get whether HTTP Digest authorization is supported. If
   6398    * supported then options #MHD_OPTION_DIGEST_AUTH_RANDOM,
   6399    * #MHD_OPTION_NONCE_NC_SIZE and
   6400    * #MHD_digest_auth_check() can be used.
   6401    */
   6402   MHD_FEATURE_DIGEST_AUTH = 12,
   6403 
   6404   /**
   6405    * Get whether postprocessor is supported. If supported then
   6406    * functions #MHD_create_post_processor(), #MHD_post_process() and
   6407    * #MHD_destroy_post_processor() can
   6408    * be used.
   6409    */
   6410   MHD_FEATURE_POSTPROCESSOR = 13,
   6411 
   6412   /**
   6413   * Get whether password encrypted private key for HTTPS daemon is
   6414   * supported. If supported then option
   6415   * ::MHD_OPTION_HTTPS_KEY_PASSWORD can be used.
   6416   */
   6417   MHD_FEATURE_HTTPS_KEY_PASSWORD = 14,
   6418 
   6419   /**
   6420    * Get whether reading files beyond 2 GiB boundary is supported.
   6421    * If supported then #MHD_create_response_from_fd(),
   6422    * #MHD_create_response_from_fd64 #MHD_create_response_from_fd_at_offset()
   6423    * and #MHD_create_response_from_fd_at_offset64() can be used with sizes and
   6424    * offsets larger than 2 GiB. If not supported value of size+offset is
   6425    * limited to 2 GiB.
   6426    */
   6427   MHD_FEATURE_LARGE_FILE = 15,
   6428 
   6429   /**
   6430    * Get whether MHD set names on generated threads.
   6431    */
   6432   MHD_FEATURE_THREAD_NAMES = 16,
   6433   MHD_THREAD_NAMES = 16,
   6434 
   6435   /**
   6436    * Get whether HTTP "Upgrade" is supported.
   6437    * If supported then #MHD_ALLOW_UPGRADE, #MHD_upgrade_action() and
   6438    * #MHD_create_response_for_upgrade() can be used.
   6439    */
   6440   MHD_FEATURE_UPGRADE = 17,
   6441 
   6442   /**
   6443    * Get whether it's safe to use same FD for multiple calls of
   6444    * #MHD_create_response_from_fd() and whether it's safe to use single
   6445    * response generated by #MHD_create_response_from_fd() with multiple
   6446    * connections at same time.
   6447    * If #MHD_is_feature_supported() return #MHD_NO for this feature then
   6448    * usage of responses with same file FD in multiple parallel threads may
   6449    * results in incorrect data sent to remote client.
   6450    * It's always safe to use same file FD in multiple responses if MHD
   6451    * is run in any single thread mode.
   6452    */
   6453   MHD_FEATURE_RESPONSES_SHARED_FD = 18,
   6454 
   6455   /**
   6456    * Get whether MHD support automatic detection of bind port number.
   6457    * @sa #MHD_DAEMON_INFO_BIND_PORT
   6458    */
   6459   MHD_FEATURE_AUTODETECT_BIND_PORT = 19,
   6460 
   6461   /**
   6462    * Get whether MHD supports automatic SIGPIPE suppression.
   6463    * If SIGPIPE suppression is not supported, application must handle
   6464    * SIGPIPE signal by itself.
   6465    */
   6466   MHD_FEATURE_AUTOSUPPRESS_SIGPIPE = 20,
   6467 
   6468   /**
   6469    * Get whether MHD use system's sendfile() function to send
   6470    * file-FD based responses over non-TLS connections.
   6471    * @note Since v0.9.56
   6472    */
   6473   MHD_FEATURE_SENDFILE = 21,
   6474 
   6475   /**
   6476    * Get whether MHD supports threads.
   6477    */
   6478   MHD_FEATURE_THREADS = 22,
   6479 
   6480   /**
   6481    * Get whether option #MHD_OPTION_HTTPS_CERT_CALLBACK2 is
   6482    * supported.
   6483    */
   6484   MHD_FEATURE_HTTPS_CERT_CALLBACK2 = 23,
   6485 
   6486   /**
   6487    * Get whether automatic parsing of HTTP Cookie header is supported.
   6488    * If disabled, no MHD_COOKIE_KIND will be generated by MHD.
   6489    * MHD versions before 0x00097701 always support cookie parsing.
   6490    * @note Available since #MHD_VERSION 0x01000200
   6491    */
   6492   MHD_FEATURE_COOKIE_PARSING = 24,
   6493 
   6494   /**
   6495    * Get whether the early version the Digest Authorization (RFC 2069) is
   6496    * supported (digest authorisation without QOP parameter).
   6497    * Since #MHD_VERSION 0x00097701 it is always supported if Digest Auth
   6498    * module is built.
   6499    * @note Available since #MHD_VERSION 0x00097701
   6500    */
   6501   MHD_FEATURE_DIGEST_AUTH_RFC2069 = 25,
   6502 
   6503   /**
   6504    * Get whether the MD5-based hashing algorithms are supported for Digest
   6505    * Authorization.
   6506    * Currently it is always supported if Digest Auth module is built
   6507    * unless manually disabled in a custom build.
   6508    * @note Available since #MHD_VERSION 0x00097701
   6509    */
   6510   MHD_FEATURE_DIGEST_AUTH_MD5 = 26,
   6511 
   6512   /**
   6513    * Get whether the SHA-256-based hashing algorithms are supported for Digest
   6514    * Authorization.
   6515    * It is always supported since #MHD_VERSION 0x00096200 if Digest Auth
   6516    * module is built unless manually disabled in a custom build.
   6517    * @note Available since #MHD_VERSION 0x00097701
   6518    */
   6519   MHD_FEATURE_DIGEST_AUTH_SHA256 = 27,
   6520 
   6521   /**
   6522    * Get whether the SHA-512/256-based hashing algorithms are supported
   6523    * for Digest Authorization.
   6524    * It it always supported since #MHD_VERSION 0x00097701 if Digest Auth
   6525    * module is built unless manually disabled in a custom build.
   6526    * @note Available since #MHD_VERSION 0x00097701
   6527    */
   6528   MHD_FEATURE_DIGEST_AUTH_SHA512_256 = 28,
   6529 
   6530   /**
   6531    * Get whether QOP with value 'auth-int' (authentication with integrity
   6532    * protection) is supported for Digest Authorization.
   6533    * Currently it is always not supported.
   6534    * @note Available since #MHD_VERSION 0x00097701
   6535    */
   6536   MHD_FEATURE_DIGEST_AUTH_AUTH_INT = 29,
   6537 
   6538   /**
   6539    * Get whether 'session' algorithms (like 'MD5-sess') are supported for Digest
   6540    * Authorization.
   6541    * Currently it is always not supported.
   6542    * @note Available since #MHD_VERSION 0x00097701
   6543    */
   6544   MHD_FEATURE_DIGEST_AUTH_ALGO_SESSION = 30,
   6545 
   6546   /**
   6547    * Get whether 'userhash' is supported for Digest Authorization.
   6548    * It is always supported since #MHD_VERSION 0x00097701 if Digest Auth
   6549    * module is built.
   6550    * @note Available since #MHD_VERSION 0x00097701
   6551    */
   6552   MHD_FEATURE_DIGEST_AUTH_USERHASH = 31,
   6553 
   6554   /**
   6555    * Get whether any of hashing algorithms is implemented by external
   6556    * function (like TLS library) and may fail due to external conditions,
   6557    * like "out-of-memory".
   6558    *
   6559    * If result is #MHD_YES then functions which use hash calculations
   6560    * like #MHD_digest_auth_calc_userhash(), #MHD_digest_auth_check3() and others
   6561    * potentially may fail even with valid input because of out-of-memory error
   6562    * or crypto accelerator device failure, however in practice such fails are
   6563    * unlikely.
   6564    * @note Available since #MHD_VERSION 0x00097701
   6565    */
   6566   MHD_FEATURE_EXTERN_HASH = 32,
   6567 
   6568   /**
   6569    * Get whether MHD was built with asserts enabled.
   6570    * For debug builds the error log is always enabled even if #MHD_USE_ERROR_LOG
   6571    * is not specified for daemon.
   6572    * @note Available since #MHD_VERSION 0x00097701
   6573    */
   6574   MHD_FEATURE_DEBUG_BUILD = 33,
   6575 
   6576   /**
   6577    * Get whether MHD was build with support for overridable FD_SETSIZE.
   6578    * This feature should be always available when the relevant platform ability
   6579    * is detected.
   6580    * @sa #MHD_OPTION_APP_FD_SETSIZE
   6581    * @note Available since #MHD_VERSION 0x00097705
   6582    */
   6583   MHD_FEATURE_FLEXIBLE_FD_SETSIZE = 34
   6584 };
   6585 
   6586 #define MHD_FEATURE_HTTPS_COOKIE_PARSING _MHD_DEPR_IN_MACRO ( \
   6587           "Value MHD_FEATURE_HTTPS_COOKIE_PARSING is deprecated, use MHD_FEATURE_COOKIE_PARSING" \
   6588           ) MHD_FEATURE_COOKIE_PARSING
   6589 
   6590 /**
   6591  * Get information about supported MHD features.
   6592  * Indicate that MHD was compiled with or without support for
   6593  * particular feature. Some features require additional support
   6594  * by kernel. Kernel support is not checked by this function.
   6595  *
   6596  * @param feature type of requested information
   6597  * @return #MHD_YES if feature is supported by MHD, #MHD_NO if
   6598  * feature is not supported or feature is unknown.
   6599  * @ingroup specialized
   6600  */
   6601 _MHD_EXTERN enum MHD_Result
   6602 MHD_is_feature_supported (enum MHD_FEATURE feature);
   6603 
   6604 
   6605 MHD_C_DECLRATIONS_FINISH_HERE_
   6606 
   6607 #endif