xref: /aosp_15_r20/external/curl/lib/getenv.c (revision 6236dae45794135f37c4eb022389c904c8b0090d)
1*6236dae4SAndroid Build Coastguard Worker /***************************************************************************
2*6236dae4SAndroid Build Coastguard Worker  *                                  _   _ ____  _
3*6236dae4SAndroid Build Coastguard Worker  *  Project                     ___| | | |  _ \| |
4*6236dae4SAndroid Build Coastguard Worker  *                             / __| | | | |_) | |
5*6236dae4SAndroid Build Coastguard Worker  *                            | (__| |_| |  _ <| |___
6*6236dae4SAndroid Build Coastguard Worker  *                             \___|\___/|_| \_\_____|
7*6236dae4SAndroid Build Coastguard Worker  *
8*6236dae4SAndroid Build Coastguard Worker  * Copyright (C) Daniel Stenberg, <[email protected]>, et al.
9*6236dae4SAndroid Build Coastguard Worker  *
10*6236dae4SAndroid Build Coastguard Worker  * This software is licensed as described in the file COPYING, which
11*6236dae4SAndroid Build Coastguard Worker  * you should have received as part of this distribution. The terms
12*6236dae4SAndroid Build Coastguard Worker  * are also available at https://curl.se/docs/copyright.html.
13*6236dae4SAndroid Build Coastguard Worker  *
14*6236dae4SAndroid Build Coastguard Worker  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15*6236dae4SAndroid Build Coastguard Worker  * copies of the Software, and permit persons to whom the Software is
16*6236dae4SAndroid Build Coastguard Worker  * furnished to do so, under the terms of the COPYING file.
17*6236dae4SAndroid Build Coastguard Worker  *
18*6236dae4SAndroid Build Coastguard Worker  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19*6236dae4SAndroid Build Coastguard Worker  * KIND, either express or implied.
20*6236dae4SAndroid Build Coastguard Worker  *
21*6236dae4SAndroid Build Coastguard Worker  * SPDX-License-Identifier: curl
22*6236dae4SAndroid Build Coastguard Worker  *
23*6236dae4SAndroid Build Coastguard Worker  ***************************************************************************/
24*6236dae4SAndroid Build Coastguard Worker 
25*6236dae4SAndroid Build Coastguard Worker #include "curl_setup.h"
26*6236dae4SAndroid Build Coastguard Worker 
27*6236dae4SAndroid Build Coastguard Worker #include <curl/curl.h>
28*6236dae4SAndroid Build Coastguard Worker #include "curl_memory.h"
29*6236dae4SAndroid Build Coastguard Worker 
30*6236dae4SAndroid Build Coastguard Worker #include "memdebug.h"
31*6236dae4SAndroid Build Coastguard Worker 
GetEnv(const char * variable)32*6236dae4SAndroid Build Coastguard Worker static char *GetEnv(const char *variable)
33*6236dae4SAndroid Build Coastguard Worker {
34*6236dae4SAndroid Build Coastguard Worker #if defined(_WIN32_WCE) || defined(CURL_WINDOWS_UWP) || \
35*6236dae4SAndroid Build Coastguard Worker   defined(__ORBIS__) || defined(__PROSPERO__) /* PlayStation 4 and 5 */
36*6236dae4SAndroid Build Coastguard Worker   (void)variable;
37*6236dae4SAndroid Build Coastguard Worker   return NULL;
38*6236dae4SAndroid Build Coastguard Worker #elif defined(_WIN32)
39*6236dae4SAndroid Build Coastguard Worker   /* This uses Windows API instead of C runtime getenv() to get the environment
40*6236dae4SAndroid Build Coastguard Worker      variable since some changes are not always visible to the latter. #4774 */
41*6236dae4SAndroid Build Coastguard Worker   char *buf = NULL;
42*6236dae4SAndroid Build Coastguard Worker   char *tmp;
43*6236dae4SAndroid Build Coastguard Worker   DWORD bufsize;
44*6236dae4SAndroid Build Coastguard Worker   DWORD rc = 1;
45*6236dae4SAndroid Build Coastguard Worker   const DWORD max = 32768; /* max env var size from MSCRT source */
46*6236dae4SAndroid Build Coastguard Worker 
47*6236dae4SAndroid Build Coastguard Worker   for(;;) {
48*6236dae4SAndroid Build Coastguard Worker     tmp = realloc(buf, rc);
49*6236dae4SAndroid Build Coastguard Worker     if(!tmp) {
50*6236dae4SAndroid Build Coastguard Worker       free(buf);
51*6236dae4SAndroid Build Coastguard Worker       return NULL;
52*6236dae4SAndroid Build Coastguard Worker     }
53*6236dae4SAndroid Build Coastguard Worker 
54*6236dae4SAndroid Build Coastguard Worker     buf = tmp;
55*6236dae4SAndroid Build Coastguard Worker     bufsize = rc;
56*6236dae4SAndroid Build Coastguard Worker 
57*6236dae4SAndroid Build Coastguard Worker     /* it is possible for rc to be 0 if the variable was found but empty.
58*6236dae4SAndroid Build Coastguard Worker        Since getenv does not make that distinction we ignore it as well. */
59*6236dae4SAndroid Build Coastguard Worker     rc = GetEnvironmentVariableA(variable, buf, bufsize);
60*6236dae4SAndroid Build Coastguard Worker     if(!rc || rc == bufsize || rc > max) {
61*6236dae4SAndroid Build Coastguard Worker       free(buf);
62*6236dae4SAndroid Build Coastguard Worker       return NULL;
63*6236dae4SAndroid Build Coastguard Worker     }
64*6236dae4SAndroid Build Coastguard Worker 
65*6236dae4SAndroid Build Coastguard Worker     /* if rc < bufsize then rc is bytes written not including null */
66*6236dae4SAndroid Build Coastguard Worker     if(rc < bufsize)
67*6236dae4SAndroid Build Coastguard Worker       return buf;
68*6236dae4SAndroid Build Coastguard Worker 
69*6236dae4SAndroid Build Coastguard Worker     /* else rc is bytes needed, try again */
70*6236dae4SAndroid Build Coastguard Worker   }
71*6236dae4SAndroid Build Coastguard Worker #else
72*6236dae4SAndroid Build Coastguard Worker   char *env = getenv(variable);
73*6236dae4SAndroid Build Coastguard Worker   return (env && env[0]) ? strdup(env) : NULL;
74*6236dae4SAndroid Build Coastguard Worker #endif
75*6236dae4SAndroid Build Coastguard Worker }
76*6236dae4SAndroid Build Coastguard Worker 
curl_getenv(const char * v)77*6236dae4SAndroid Build Coastguard Worker char *curl_getenv(const char *v)
78*6236dae4SAndroid Build Coastguard Worker {
79*6236dae4SAndroid Build Coastguard Worker   return GetEnv(v);
80*6236dae4SAndroid Build Coastguard Worker }
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