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/*
* Copyright (C) 2010 Apple Inc. 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. 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 INC. 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.
*/
#include "config.h"
#include "OSAllocator.h"
#if OS(UNIX) && !OS(SYMBIAN)
#include <errno.h>
#include <sys/mman.h>
#include <wtf/Assertions.h>
#include <wtf/UnusedParam.h>
namespace WTF {
void* OSAllocator::reserve(size_t bytes)
{
// From a bookkeeping perspective, POSIX reservations start out in the committed state.
void* result = mmap(0, bytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
if (result == MAP_FAILED)
CRASH();
#if HAVE(MADV_FREE_REUSE)
while (madvise(result, bytes, MADV_FREE_REUSABLE) == -1 && errno == EAGAIN) { }
#endif
return result;
}
void* OSAllocator::reserveAndCommit(size_t bytes)
{
// From a bookkeeping perspective, POSIX reservations start out in the committed state.
return reserve(bytes);
}
void OSAllocator::commit(void* address, size_t bytes)
{
#if HAVE(MADV_FREE_REUSE)
while (madvise(address, bytes, MADV_FREE_REUSE) == -1 && errno == EAGAIN) { }
#else
UNUSED_PARAM(address);
UNUSED_PARAM(bytes);
#endif
}
void OSAllocator::decommit(void* address, size_t bytes)
{
#if HAVE(MADV_FREE_REUSE)
while (madvise(address, bytes, MADV_FREE_REUSABLE) == -1 && errno == EAGAIN) { }
#elif HAVE(MADV_FREE)
while (madvise(address, bytes, MADV_FREE) == -1 && errno == EAGAIN) { }
#elif HAVE(MADV_DONTNEED)
while (madvise(address, bytes, MADV_DONTNEED) == -1 && errno == EAGAIN) { }
#else
UNUSED_PARAM(address);
UNUSED_PARAM(bytes);
#endif
}
void OSAllocator::release(void* address, size_t bytes)
{
munmap(address, bytes);
}
} // namespace WTF
#endif
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