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/* MIT License
*
* Copyright (c) 1998 Massachusetts Institute of Technology
* Copyright (c) 2004 Daniel Stenberg
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
* SPDX-License-Identifier: MIT
*/
#include "ares_setup.h"
#include "ares.h"
#include "ares_private.h"
/* library-private global and unique instance vars */
#if defined(ANDROID) || defined(__ANDROID__)
# include "ares_android.h"
#endif
/* library-private global vars with source visibility restricted to this file */
static unsigned int ares_initialized;
static int ares_init_flags;
/* library-private global vars with visibility across the whole library */
/* Some systems may return either NULL or a valid pointer on malloc(0). c-ares
* should never call malloc(0) so lets return NULL so we're more likely to find
* an issue if it were to occur. */
static void *default_malloc(size_t size)
{
if (size == 0) {
return NULL;
}
return malloc(size);
}
#if defined(WIN32)
/* We need indirections to handle Windows DLL rules. */
static void *default_realloc(void *p, size_t size)
{
return realloc(p, size);
}
static void default_free(void *p)
{
free(p);
}
#else
# define default_realloc realloc
# define default_free free
#endif
void *(*ares_malloc)(size_t size) = default_malloc;
void *(*ares_realloc)(void *ptr, size_t size) = default_realloc;
void (*ares_free)(void *ptr) = default_free;
void *ares_malloc_zero(size_t size)
{
void *ptr = ares_malloc(size);
if (ptr != NULL) {
memset(ptr, 0, size);
}
return ptr;
}
void *ares_realloc_zero(void *ptr, size_t orig_size, size_t new_size)
{
void *p = ares_realloc(ptr, new_size);
if (p == NULL) {
return NULL;
}
if (new_size > orig_size) {
memset((unsigned char *)p + orig_size, 0, new_size - orig_size);
}
return p;
}
int ares_library_init_unsafe(int flags)
{
if (ares_initialized) {
ares_initialized++;
return ARES_SUCCESS;
}
ares_initialized++;
/* NOTE: ARES_LIB_INIT_WIN32 flag no longer used */
ares_init_flags = flags;
return ARES_SUCCESS;
}
int ares_library_init_mem(int flags, void *(*amalloc)(size_t size),
void (*afree)(void *ptr),
void *(*arealloc)(void *ptr, size_t size))
{
if (amalloc) {
ares_malloc = amalloc;
}
if (arealloc) {
ares_realloc = arealloc;
}
if (afree) {
ares_free = afree;
}
return ares_library_init(flags);
}
void ares_library_cleanup_unsafe(void)
{
if (!ares_initialized) {
return;
}
ares_initialized--;
if (ares_initialized) {
return;
}
/* NOTE: ARES_LIB_INIT_WIN32 flag no longer used */
#if defined(ANDROID) || defined(__ANDROID__)
ares_library_cleanup_android();
#endif
ares_init_flags = ARES_LIB_INIT_NONE;
ares_malloc = malloc;
ares_realloc = realloc;
ares_free = free;
}
int ares_library_initialized_unsafe(void)
{
#ifdef USE_WINSOCK
if (!ares_initialized) {
return ARES_ENOTINITIALIZED;
}
#endif
return ARES_SUCCESS;
}
#include "atomic.h"
static atomic_t ares_init_lock;
int ares_library_init(int flags)
{
acquire_lock(&ares_init_lock);
int res = ares_library_init_unsafe(flags);
release_lock(&ares_init_lock);
return res;
}
void ares_library_cleanup(void)
{
acquire_lock(&ares_init_lock);
ares_library_cleanup_unsafe();
release_lock(&ares_init_lock);
}
int ares_library_initialized(void)
{
acquire_lock(&ares_init_lock);
int res = ares_library_initialized_unsafe();
release_lock(&ares_init_lock);
return res;
}
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