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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "VolatileBuffer.h"
#include "mozilla/Assertions.h"
#include "mozilla/mozalloc.h"
#ifdef MOZ_MEMORY
int posix_memalign(void** memptr, size_t alignment, size_t size);
#endif
namespace mozilla {
VolatileBuffer::VolatileBuffer()
: mMutex("VolatileBuffer")
, mBuf(nullptr)
, mSize(0)
, mLockCount(0)
{
}
bool VolatileBuffer::Init(size_t aSize, size_t aAlignment)
{
MOZ_ASSERT(!mSize && !mBuf, "Init called twice");
MOZ_ASSERT(!(aAlignment % sizeof(void *)),
"Alignment must be multiple of pointer size");
mSize = aSize;
#if defined(MOZ_MEMORY)
if (posix_memalign(&mBuf, aAlignment, aSize) != 0) {
return false;
}
#elif defined(HAVE_POSIX_MEMALIGN)
if (moz_posix_memalign(&mBuf, aAlignment, aSize) != 0) {
return false;
}
#else
#error "No memalign implementation found"
#endif
return !!mBuf;
}
VolatileBuffer::~VolatileBuffer()
{
MOZ_ASSERT(mLockCount == 0, "Being destroyed with non-zero lock count?");
free(mBuf);
}
bool
VolatileBuffer::Lock(void** aBuf)
{
MutexAutoLock lock(mMutex);
MOZ_ASSERT(mBuf, "Attempting to lock an uninitialized VolatileBuffer");
*aBuf = mBuf;
mLockCount++;
return true;
}
void
VolatileBuffer::Unlock()
{
MutexAutoLock lock(mMutex);
mLockCount--;
MOZ_ASSERT(mLockCount >= 0, "VolatileBuffer unlocked too many times!");
}
bool
VolatileBuffer::OnHeap() const
{
return true;
}
size_t
VolatileBuffer::HeapSizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
{
return aMallocSizeOf(mBuf);
}
size_t
VolatileBuffer::NonHeapSizeOfExcludingThis() const
{
return 0;
}
} // namespace mozilla
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