/*

 * Copyright (C) 2005, 2006, 2007, 2010 Apple Inc. All rights reserved.

 *           (C) 2007 Graham Dennis (graham.dennis@gmail.com)

 *           (C) 2007 Eric Seidel <eric@webkit.org>

 *

 * 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.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of

 *     its contributors may be used to endorse or promote products derived

 *     from this software without specific prior written permission. 

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "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 APPLE OR ITS CONTRIBUTORS 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.

 */

#import "config.h" 

#import "CheckedMalloc.h"

#import <malloc/malloc.h>

#import <sys/mman.h>

static void* (*savedMalloc)(malloc_zone_t*, size_t);

static void* (*savedRealloc)(malloc_zone_t*, void*, size_t);

static void* checkedMalloc(malloc_zone_t* zone, size_t size)

{

    if (size >= 0x10000000)

        return 0;

    return savedMalloc(zone, size);

}

static void* checkedRealloc(malloc_zone_t* zone, void* ptr, size_t size)

{

    if (size >= 0x10000000)

        return 0;

    return savedRealloc(zone, ptr, size);

}

void makeLargeMallocFailSilently()

{

    malloc_zone_t* zone = malloc_default_zone();

#if !defined(BUILDING_ON_TIGER) && !defined(BUILDING_ON_LEOPARD) && !defined(BUILDING_ON_SNOW_LEOPARD)

    vm_address_t pageStart = reinterpret_cast<vm_address_t>(zone) & static_cast<vm_size_t>(~(getpagesize() - 1));

    vm_size_t len = reinterpret_cast<vm_address_t>(zone) - pageStart + sizeof(malloc_zone_t);

    mprotect(reinterpret_cast<void*>(pageStart), len, PROT_READ | PROT_WRITE);

#endif

    savedMalloc = zone->malloc;

    savedRealloc = zone->realloc;

    zone->malloc = checkedMalloc;

    zone->realloc = checkedRealloc;

#if !defined(BUILDING_ON_TIGER) && !defined(BUILDING_ON_LEOPARD) && !defined(BUILDING_ON_SNOW_LEOPARD)

    mprotect(reinterpret_cast<void*>(pageStart), len, PROT_READ);

#endif

}