quickjs-tart

quickjs-based runtime for wallet-core logic
Log | Files | Refs | README | LICENSE

getenv.c (2401B)

      1 /***************************************************************************
      2  *                                  _   _ ____  _
      3  *  Project                     ___| | | |  _ \| |
      4  *                             / __| | | | |_) | |
      5  *                            | (__| |_| |  _ <| |___
      6  *                             \___|\___/|_| \_\_____|
      7  *
      8  * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
      9  *
     10  * This software is licensed as described in the file COPYING, which
     11  * you should have received as part of this distribution. The terms
     12  * are also available at https://curl.se/docs/copyright.html.
     13  *
     14  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
     15  * copies of the Software, and permit persons to whom the Software is
     16  * furnished to do so, under the terms of the COPYING file.
     17  *
     18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
     19  * KIND, either express or implied.
     20  *
     21  * SPDX-License-Identifier: curl
     22  *
     23  ***************************************************************************/
     24 
     25 #include "curl_setup.h"
     26 
     27 #include <curl/curl.h>
     28 #include "curl_memory.h"
     29 
     30 #include "memdebug.h"
     31 
     32 static char *GetEnv(const char *variable)
     33 {
     34 #if defined(CURL_WINDOWS_UWP) || defined(UNDER_CE) || \
     35   defined(__ORBIS__) || defined(__PROSPERO__) /* PlayStation 4 and 5 */
     36   (void)variable;
     37   return NULL;
     38 #elif defined(_WIN32)
     39   /* This uses Windows API instead of C runtime getenv() to get the environment
     40      variable since some changes are not always visible to the latter. #4774 */
     41   char *buf = NULL;
     42   char *tmp;
     43   DWORD bufsize;
     44   DWORD rc = 1;
     45   const DWORD max = 32768; /* max env var size from MSCRT source */
     46 
     47   for(;;) {
     48     tmp = realloc(buf, rc);
     49     if(!tmp) {
     50       free(buf);
     51       return NULL;
     52     }
     53 
     54     buf = tmp;
     55     bufsize = rc;
     56 
     57     /* it is possible for rc to be 0 if the variable was found but empty.
     58        Since getenv does not make that distinction we ignore it as well. */
     59     rc = GetEnvironmentVariableA(variable, buf, bufsize);
     60     if(!rc || rc == bufsize || rc > max) {
     61       free(buf);
     62       return NULL;
     63     }
     64 
     65     /* if rc < bufsize then rc is bytes written not including null */
     66     if(rc < bufsize)
     67       return buf;
     68 
     69     /* else rc is bytes needed, try again */
     70   }
     71 #else
     72   char *env = getenv(variable);
     73   return (env && env[0]) ? strdup(env) : NULL;
     74 #endif
     75 }
     76 
     77 char *curl_getenv(const char *v)
     78 {
     79   return GetEnv(v);
     80 }