dmmlib/src/glibc_hooks.c

/*
 *   Copyright Rubber Duck Software P.C.
 *
 *   Licensed under the Apache License, Version 2.0 (the "License");
 *   you may not use this file except in compliance with the License.
 *   You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 *   Unless required by applicable law or agreed to in writing, software
 *   distributed under the License is distributed on an "AS IS" BASIS,
 *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *   See the License for the specific language governing permissions and
 *   limitations under the License.
 *
 */

/**
 * @file   src/glibc_hooks.c
 * @author Ioannis Koutras (joko@microlab.ntua.gr)
 * @date   October 2013
 *
 * @brief  Override GLIBC hooks with dmmlib's functions
 */

#include <features.h>

#if (defined(__GLIBC__) && !defined(__UCLIBC__))

#include <stddef.h>
#include <dmmlib/dmmlib.h>

/*
 * glibc provides the RTLD_DEEPBIND flag for dlopen which can make it possible
 * to inconsistently reference libc's malloc(3)-compatible functions
 * (https://bugzilla.mozilla.org/show_bug.cgi?id=493541).
 *
 * These definitions interpose hooks in glibc. The functions are actually
 * passed an extra argument for the caller return address, which will be
 * ignored.
 */

void (* __free_hook)(void *ptr) = free;
void *(* __malloc_hook)(size_t size) = malloc;
void *(* __realloc_hook)(void *ptr, size_t size) = realloc;
#ifdef WITH_MEMALIGN
void *(* __memalign_hook)(size_t alignment, size_t size) = memalign;
#endif /* WITH_MEMALIGN */

#endif /* __GLIBC__ && !__UCLIBC__ */