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/*
* Copyright (c) 2012, 2013 ARM Ltd
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the company may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "local-malloc.h"
/*
* Algorithm:
* Maintain a global free chunk_t single link list, headed by global
* variable __malloc_free_list.
* When free, insert the to-be-freed chunk_t into free list. The place to
* insert should make sure all chunks are sorted by address from low to
* high. Then merge with neighbor chunks if adjacent.
*/
void
__malloc_free(void *free_p)
{
chunk_t *p_to_free;
chunk_t **p, *r;
if (free_p == NULL)
return;
p_to_free = ptr_to_chunk(free_p);
#ifdef __MALLOC_CLEAR_FREED
memset(p_to_free, 0, chunk_usable(p_to_free));
#else
p_to_free->next = NULL;
#endif
#if MALLOC_DEBUG
__malloc_validate_block(p_to_free);
#endif
MALLOC_LOCK;
for (p = &__malloc_free_list; (r = *p) != NULL; p = &r->next) {
/* Insert in address order */
if (p_to_free <= r) {
/* Check for double free */
if (p_to_free == r) {
errno = ENOMEM;
goto unlock;
}
break;
}
/* Merge blocks together */
if (chunk_after(r) == p_to_free) {
*_size_ref(r) += _size(p_to_free);
p_to_free = r;
r = r->next;
goto no_insert;
}
}
p_to_free->next = r;
*p = p_to_free;
no_insert:
/* Merge blocks together */
if (chunk_after(p_to_free) == r) {
#ifdef __GNUCLIKE_PRAGMA_DIAGNOSTIC
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wpragmas"
#pragma GCC diagnostic ignored "-Wunknown-warning-option"
#pragma GCC diagnostic ignored "-Wanalyzer-null-dereference"
#endif
*_size_ref(p_to_free) += _size(r);
#ifdef __GNUCLIKE_PRAGMA_DIAGNOSTIC
#pragma GCC diagnostic pop
#endif
p_to_free->next = r->next;
}
unlock:
MALLOC_UNLOCK;
}
#ifdef __strong_reference
#if defined(__GNUCLIKE_PRAGMA_DIAGNOSTIC) && !defined(__clang__)
#pragma GCC diagnostic ignored "-Wmissing-attributes"
#endif
__strong_reference(__malloc_free, free);
__strong_reference(__malloc_free, cfree);
#else
void
cfree(void *ptr)
{
free(ptr);
}
#endif