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 32static char *GetEnv(const char *variable) 33{ 34#if defined(_WIN32_WCE) || defined(CURL_WINDOWS_APP) || \ 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 aren't 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's possible for rc to be 0 if the variable was found but empty. 58 Since getenv doesn't 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 77char *curl_getenv(const char *v) 78{ 79 return GetEnv(v); 80} 81