SDL_getenv.c
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#if defined(__clang_analyzer__) && !defined(SDL_DISABLE_ANALYZE_MACROS)
#define SDL_DISABLE_ANALYZE_MACROS 1
#endif
#include "../SDL_internal.h"
#if defined(__WIN32__)
#include "../core/windows/SDL_windows.h"
#endif
#if defined(__ANDROID__)
#include "../core/android/SDL_android.h"
#endif
#include "SDL_stdinc.h"
#if defined(__WIN32__) && (!defined(HAVE_SETENV) || !defined(HAVE_GETENV))
/* Note this isn't thread-safe! */
static char *SDL_envmem = NULL; /* Ugh, memory leak */
static size_t SDL_envmemlen = 0;
#endif
/* Put a variable into the environment */
/* Note: Name may not contain a '=' character. (Reference: http://www.unix.com/man-page/Linux/3/setenv/) */
#if defined(HAVE_SETENV)
int
SDL_setenv(const char *name, const char *value, int overwrite)
{
/* Input validation */
if (!name || SDL_strlen(name) == 0 || SDL_strchr(name, '=') != NULL || !value) {
return (-1);
}
return setenv(name, value, overwrite);
}
#elif defined(__WIN32__)
int
SDL_setenv(const char *name, const char *value, int overwrite)
{
/* Input validation */
if (!name || SDL_strlen(name) == 0 || SDL_strchr(name, '=') != NULL || !value) {
return (-1);
}
if (!overwrite) {
if (GetEnvironmentVariableA(name, NULL, 0) > 0) {
return 0; /* asked not to overwrite existing value. */
}
}
if (!SetEnvironmentVariableA(name, *value ? value : NULL)) {
return -1;
}
return 0;
}
/* We have a real environment table, but no real setenv? Fake it w/ putenv. */
#elif (defined(HAVE_GETENV) && defined(HAVE_PUTENV) && !defined(HAVE_SETENV))
int
SDL_setenv(const char *name, const char *value, int overwrite)
{
size_t len;
char *new_variable;
/* Input validation */
if (!name || SDL_strlen(name) == 0 || SDL_strchr(name, '=') != NULL || !value) {
return (-1);
}
if (getenv(name) != NULL) {
if (overwrite) {
unsetenv(name);
} else {
return 0; /* leave the existing one there. */
}
}
/* This leaks. Sorry. Get a better OS so we don't have to do this. */
len = SDL_strlen(name) + SDL_strlen(value) + 2;
new_variable = (char *) SDL_malloc(len);
if (!new_variable) {
return (-1);
}
SDL_snprintf(new_variable, len, "%s=%s", name, value);
return putenv(new_variable);
}
#else /* roll our own */
static char **SDL_env = (char **) 0;
int
SDL_setenv(const char *name, const char *value, int overwrite)
{
int added;
int len, i;
char **new_env;
char *new_variable;
/* Input validation */
if (!name || SDL_strlen(name) == 0 || SDL_strchr(name, '=') != NULL || !value) {
return (-1);
}
/* See if it already exists */
if (!overwrite && SDL_getenv(name)) {
return 0;
}
/* Allocate memory for the variable */
len = SDL_strlen(name) + SDL_strlen(value) + 2;
new_variable = (char *) SDL_malloc(len);
if (!new_variable) {
return (-1);
}
SDL_snprintf(new_variable, len, "%s=%s", name, value);
value = new_variable + SDL_strlen(name) + 1;
name = new_variable;
/* Actually put it into the environment */
added = 0;
i = 0;
if (SDL_env) {
/* Check to see if it's already there... */
len = (value - name);
for (; SDL_env[i]; ++i) {
if (SDL_strncmp(SDL_env[i], name, len) == 0) {
break;
}
}
/* If we found it, just replace the entry */
if (SDL_env[i]) {
SDL_free(SDL_env[i]);
SDL_env[i] = new_variable;
added = 1;
}
}
/* Didn't find it in the environment, expand and add */
if (!added) {
new_env = SDL_realloc(SDL_env, (i + 2) * sizeof(char *));
if (new_env) {
SDL_env = new_env;
SDL_env[i++] = new_variable;
SDL_env[i++] = (char *) 0;
added = 1;
} else {
SDL_free(new_variable);
}
}
return (added ? 0 : -1);
}
#endif
/* Retrieve a variable named "name" from the environment */
#if defined(HAVE_GETENV)
char *
SDL_getenv(const char *name)
{
#if defined(__ANDROID__)
/* Make sure variables from the application manifest are available */
Android_JNI_GetManifestEnvironmentVariables();
#endif
/* Input validation */
if (!name || !*name) {
return NULL;
}
return getenv(name);
}
#elif defined(__WIN32__)
char *
SDL_getenv(const char *name)
{
size_t bufferlen;
/* Input validation */
if (!name || SDL_strlen(name)==0) {
return NULL;
}
bufferlen =
GetEnvironmentVariableA(name, SDL_envmem, (DWORD) SDL_envmemlen);
if (bufferlen == 0) {
return NULL;
}
if (bufferlen > SDL_envmemlen) {
char *newmem = (char *) SDL_realloc(SDL_envmem, bufferlen);
if (newmem == NULL) {
return NULL;
}
SDL_envmem = newmem;
SDL_envmemlen = bufferlen;
GetEnvironmentVariableA(name, SDL_envmem, (DWORD) SDL_envmemlen);
}
return SDL_envmem;
}
#else
char *
SDL_getenv(const char *name)
{
int len, i;
char *value;
/* Input validation */
if (!name || SDL_strlen(name)==0) {
return NULL;
}
value = (char *) 0;
if (SDL_env) {
len = SDL_strlen(name);
for (i = 0; SDL_env[i] && !value; ++i) {
if ((SDL_strncmp(SDL_env[i], name, len) == 0) &&
(SDL_env[i][len] == '=')) {
value = &SDL_env[i][len + 1];
}
}
}
return value;
}
#endif
#ifdef TEST_MAIN
#include <stdio.h>
int
main(int argc, char *argv[])
{
char *value;
printf("Checking for non-existent variable... ");
fflush(stdout);
if (!SDL_getenv("EXISTS")) {
printf("okay\n");
} else {
printf("failed\n");
}
printf("Setting FIRST=VALUE1 in the environment... ");
fflush(stdout);
if (SDL_setenv("FIRST", "VALUE1", 0) == 0) {
printf("okay\n");
} else {
printf("failed\n");
}
printf("Getting FIRST from the environment... ");
fflush(stdout);
value = SDL_getenv("FIRST");
if (value && (SDL_strcmp(value, "VALUE1") == 0)) {
printf("okay\n");
} else {
printf("failed\n");
}
printf("Setting SECOND=VALUE2 in the environment... ");
fflush(stdout);
if (SDL_setenv("SECOND", "VALUE2", 0) == 0) {
printf("okay\n");
} else {
printf("failed\n");
}
printf("Getting SECOND from the environment... ");
fflush(stdout);
value = SDL_getenv("SECOND");
if (value && (SDL_strcmp(value, "VALUE2") == 0)) {
printf("okay\n");
} else {
printf("failed\n");
}
printf("Setting FIRST=NOVALUE in the environment... ");
fflush(stdout);
if (SDL_setenv("FIRST", "NOVALUE", 1) == 0) {
printf("okay\n");
} else {
printf("failed\n");
}
printf("Getting FIRST from the environment... ");
fflush(stdout);
value = SDL_getenv("FIRST");
if (value && (SDL_strcmp(value, "NOVALUE") == 0)) {
printf("okay\n");
} else {
printf("failed\n");
}
printf("Checking for non-existent variable... ");
fflush(stdout);
if (!SDL_getenv("EXISTS")) {
printf("okay\n");
} else {
printf("failed\n");
}
return (0);
}
#endif /* TEST_MAIN */
/* vi: set ts=4 sw=4 expandtab: */
SDL_getenv
char * SDL_getenv(const char *name)
Definition: SDL_getenv.c:219
SDL_realloc
#define SDL_realloc
Definition: SDL_dynapi_overrides.h:376
SDL_strncmp
#define SDL_strncmp
Definition: SDL_dynapi_overrides.h:418
SDL_env
static char ** SDL_env
Definition: SDL_getenv.c:108
len
GLenum GLsizei len
Definition: SDL_opengl_glext.h:2926
name
GLuint const GLchar * name
Definition: SDL_opengl_glext.h:660
SDL_strchr
#define SDL_strchr
Definition: SDL_dynapi_overrides.h:401
SDL_free
#define SDL_free
Definition: SDL_dynapi_overrides.h:377
SDL_setenv
int SDL_setenv(const char *name, const char *value, int overwrite)
Definition: SDL_getenv.c:110
value
GLsizei const GLfloat * value
Definition: SDL_opengl_glext.h:698
i
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50
NULL
#define NULL
Definition: begin_code.h:164
Android_JNI_GetManifestEnvironmentVariables
void Android_JNI_GetManifestEnvironmentVariables(void)
SDL_stdinc.h
SDL_strlen
#define SDL_strlen
Definition: SDL_dynapi_overrides.h:393
SDL_snprintf
#define SDL_snprintf
Definition: SDL_dynapi_overrides.h:40
SDL_malloc
#define SDL_malloc
Definition: SDL_dynapi_overrides.h:374
main
#define main
Definition: SDL_main.h:111
SDL_strcmp
#define SDL_strcmp
Definition: SDL_dynapi_overrides.h:417