gecko-dev/mozglue/interposers/env_interposer.cpp

80 строки
2.1 KiB
C++

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include <pthread.h>
#include <string.h>
#include <unistd.h>
#include "InterposerHelper.h"
// The interposers in this file cover all the functions used to access the
// environment (getenv(), putenv(), setenv(), unsetenv() and clearenv()). They
// all use the mutex below for synchronization to prevent races that caused
// startup crashes, see bug 1752703.
static pthread_mutex_t gEnvLock = PTHREAD_MUTEX_INITIALIZER;
static char* internal_getenv(const char* aName) {
if (environ == nullptr || aName[0] == '\0') {
return nullptr;
}
size_t len = strlen(aName);
for (char** env_ptr = environ; *env_ptr != nullptr; ++env_ptr) {
if ((aName[0] == (*env_ptr)[0]) && (strncmp(aName, *env_ptr, len) == 0) &&
((*env_ptr)[len] == '=')) {
return *env_ptr + len + 1;
}
}
return nullptr;
}
extern "C" {
MFBT_API char* getenv(const char* name) {
pthread_mutex_lock(&gEnvLock);
char* result = internal_getenv(name);
pthread_mutex_unlock(&gEnvLock);
return result;
}
MFBT_API int putenv(char* string) {
static const auto real_putenv = GET_REAL_SYMBOL(putenv);
pthread_mutex_lock(&gEnvLock);
int result = real_putenv(string);
pthread_mutex_unlock(&gEnvLock);
return result;
}
MFBT_API int setenv(const char* name, const char* value, int replace) {
static const auto real_setenv = GET_REAL_SYMBOL(setenv);
pthread_mutex_lock(&gEnvLock);
int result = real_setenv(name, value, replace);
pthread_mutex_unlock(&gEnvLock);
return result;
}
MFBT_API int unsetenv(const char* name) {
static const auto real_unsetenv = GET_REAL_SYMBOL(unsetenv);
pthread_mutex_lock(&gEnvLock);
int result = real_unsetenv(name);
pthread_mutex_unlock(&gEnvLock);
return result;
}
MFBT_API int clearenv(void) {
static const auto real_clearenv = GET_REAL_SYMBOL(clearenv);
pthread_mutex_lock(&gEnvLock);
int result = real_clearenv();
pthread_mutex_unlock(&gEnvLock);
return result;
}
} // extern "C"