pingpong.h (6137B)
1 #ifndef HEADER_CURL_PINGPONG_H 2 #define HEADER_CURL_PINGPONG_H 3 /*************************************************************************** 4 * _ _ ____ _ 5 * Project ___| | | | _ \| | 6 * / __| | | | |_) | | 7 * | (__| |_| | _ <| |___ 8 * \___|\___/|_| \_\_____| 9 * 10 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 11 * 12 * This software is licensed as described in the file COPYING, which 13 * you should have received as part of this distribution. The terms 14 * are also available at https://curl.se/docs/copyright.html. 15 * 16 * You may opt to use, copy, modify, merge, publish, distribute and/or sell 17 * copies of the Software, and permit persons to whom the Software is 18 * furnished to do so, under the terms of the COPYING file. 19 * 20 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY 21 * KIND, either express or implied. 22 * 23 * SPDX-License-Identifier: curl 24 * 25 ***************************************************************************/ 26 27 #include "curl_setup.h" 28 29 #if !defined(CURL_DISABLE_IMAP) || !defined(CURL_DISABLE_FTP) || \ 30 !defined(CURL_DISABLE_POP3) || !defined(CURL_DISABLE_SMTP) 31 #define USE_PINGPONG 32 #endif 33 34 /* forward-declaration, this is defined in urldata.h */ 35 struct connectdata; 36 37 typedef enum { 38 PPTRANSFER_BODY, /* yes do transfer a body */ 39 PPTRANSFER_INFO, /* do still go through to get info/headers */ 40 PPTRANSFER_NONE /* do not get anything and do not get info */ 41 } curl_pp_transfer; 42 43 /* 44 * 'pingpong' is the generic struct used for protocols doing server<->client 45 * conversations in a back-and-forth style such as FTP, IMAP, POP3, SMTP etc. 46 * 47 * It holds response cache and non-blocking sending data. 48 */ 49 struct pingpong { 50 size_t nread_resp; /* number of bytes currently read of a server response */ 51 char *sendthis; /* pointer to a buffer that is to be sent to the server */ 52 size_t sendleft; /* number of bytes left to send from the sendthis buffer */ 53 size_t sendsize; /* total size of the sendthis buffer */ 54 struct curltime response; /* set to Curl_now() when a command has been sent 55 off, used to time-out response reading */ 56 timediff_t response_time; /* When no timeout is given, this is the amount of 57 milliseconds we await for a server response. */ 58 struct dynbuf sendbuf; 59 struct dynbuf recvbuf; 60 size_t overflow; /* number of bytes left after a final response line */ 61 size_t nfinal; /* number of bytes in the final response line, which 62 after a match is first in the receive buffer */ 63 64 /* Function pointers the protocols MUST implement and provide for the 65 pingpong layer to function */ 66 67 CURLcode (*statemachine)(struct Curl_easy *data, struct connectdata *conn); 68 bool (*endofresp)(struct Curl_easy *data, struct connectdata *conn, 69 const char *ptr, size_t len, int *code); 70 BIT(initialised); 71 BIT(pending_resp); /* set TRUE when a server response is pending or in 72 progress, and is cleared once the last response is 73 read */ 74 }; 75 76 #define PINGPONG_SETUP(pp,s,e) \ 77 do { \ 78 (pp)->response_time = RESP_TIMEOUT; \ 79 (pp)->statemachine = s; \ 80 (pp)->endofresp = e; \ 81 } while(0) 82 83 /* 84 * Curl_pp_statemach() 85 * 86 * called repeatedly until done. Set 'wait' to make it wait a while on the 87 * socket if there is no traffic. 88 */ 89 CURLcode Curl_pp_statemach(struct Curl_easy *data, struct pingpong *pp, 90 bool block, bool disconnecting); 91 92 /* initialize stuff to prepare for reading a fresh new response */ 93 void Curl_pp_init(struct pingpong *pp); 94 95 /* Returns timeout in ms. 0 or negative number means the timeout has already 96 triggered */ 97 timediff_t Curl_pp_state_timeout(struct Curl_easy *data, 98 struct pingpong *pp, bool disconnecting); 99 100 101 /*********************************************************************** 102 * 103 * Curl_pp_sendf() 104 * 105 * Send the formatted string as a command to a pingpong server. Note that 106 * the string should not have any CRLF appended, as this function will 107 * append the necessary things itself. 108 * 109 * made to never block 110 */ 111 CURLcode Curl_pp_sendf(struct Curl_easy *data, 112 struct pingpong *pp, 113 const char *fmt, ...) CURL_PRINTF(3, 4); 114 115 /*********************************************************************** 116 * 117 * Curl_pp_vsendf() 118 * 119 * Send the formatted string as a command to a pingpong server. Note that 120 * the string should not have any CRLF appended, as this function will 121 * append the necessary things itself. 122 * 123 * made to never block 124 */ 125 CURLcode Curl_pp_vsendf(struct Curl_easy *data, 126 struct pingpong *pp, 127 const char *fmt, 128 va_list args) CURL_PRINTF(3, 0); 129 130 /* 131 * Curl_pp_readresp() 132 * 133 * Reads a piece of a server response. 134 */ 135 CURLcode Curl_pp_readresp(struct Curl_easy *data, 136 int sockindex, 137 struct pingpong *pp, 138 int *code, /* return the server code if done */ 139 size_t *size); /* size of the response */ 140 141 bool Curl_pp_needs_flush(struct Curl_easy *data, 142 struct pingpong *pp); 143 144 CURLcode Curl_pp_flushsend(struct Curl_easy *data, 145 struct pingpong *pp); 146 147 /* call this when a pingpong connection is disconnected */ 148 CURLcode Curl_pp_disconnect(struct pingpong *pp); 149 150 int Curl_pp_getsock(struct Curl_easy *data, struct pingpong *pp, 151 curl_socket_t *socks); 152 153 154 /*********************************************************************** 155 * 156 * Curl_pp_moredata() 157 * 158 * Returns whether there are still more data in the cache and so a call 159 * to Curl_pp_readresp() will not block. 160 */ 161 bool Curl_pp_moredata(struct pingpong *pp); 162 163 #endif /* HEADER_CURL_PINGPONG_H */