gecko-dev/gfx/thebes/gfxSharedImageSurface.h

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3.6 KiB
C++

// vim:set ts=4 sts=4 sw=4 et cin:
/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* 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/. */
#ifndef GFX_SHARED_IMAGESURFACE_H
#define GFX_SHARED_IMAGESURFACE_H
#include "mozilla/ipc/Shmem.h"
#include "mozilla/ipc/SharedMemory.h"
#include "gfxASurface.h"
#include "gfxImageSurface.h"
class THEBES_API gfxSharedImageSurface : public gfxImageSurface {
typedef mozilla::ipc::SharedMemory SharedMemory;
typedef mozilla::ipc::Shmem Shmem;
public:
virtual ~gfxSharedImageSurface();
/**
* Return a new gfxSharedImageSurface around a shmem segment newly
* allocated by this function. |aAllocator| is the object used to
* allocate the new shmem segment. Null is returned if creating
* the surface failed.
*
* NB: the *caller* is responsible for freeing the Shmem allocated
* by this function.
*/
template<class ShmemAllocator>
static already_AddRefed<gfxSharedImageSurface>
Create(ShmemAllocator* aAllocator,
const gfxIntSize& aSize,
gfxImageFormat aFormat,
SharedMemory::SharedMemoryType aShmType = SharedMemory::TYPE_BASIC)
{
return Create<ShmemAllocator, false>(aAllocator, aSize, aFormat, aShmType);
}
/**
* Return a new gfxSharedImageSurface that wraps a shmem segment
* already created by the Create() above. Bad things will happen
* if an attempt is made to wrap any other shmem segment. Null is
* returned if creating the surface failed.
*/
static already_AddRefed<gfxSharedImageSurface>
Open(const Shmem& aShmem);
template<class ShmemAllocator>
static already_AddRefed<gfxSharedImageSurface>
CreateUnsafe(ShmemAllocator* aAllocator,
const gfxIntSize& aSize,
gfxImageFormat aFormat,
SharedMemory::SharedMemoryType aShmType = SharedMemory::TYPE_BASIC)
{
return Create<ShmemAllocator, true>(aAllocator, aSize, aFormat, aShmType);
}
Shmem& GetShmem() { return mShmem; }
static bool IsSharedImage(gfxASurface *aSurface);
private:
gfxSharedImageSurface(const gfxIntSize&, gfxImageFormat, const Shmem&);
void WriteShmemInfo();
static size_t GetAlignedSize(const gfxIntSize&, long aStride);
template<class ShmemAllocator, bool Unsafe>
static already_AddRefed<gfxSharedImageSurface>
Create(ShmemAllocator* aAllocator,
const gfxIntSize& aSize,
gfxImageFormat aFormat,
SharedMemory::SharedMemoryType aShmType)
{
if (!CheckSurfaceSize(aSize))
return nullptr;
Shmem shmem;
long stride = ComputeStride(aSize, aFormat);
size_t size = GetAlignedSize(aSize, stride);
if (!Unsafe) {
if (!aAllocator->AllocShmem(size, aShmType, &shmem))
return nullptr;
} else {
if (!aAllocator->AllocUnsafeShmem(size, aShmType, &shmem))
return nullptr;
}
nsRefPtr<gfxSharedImageSurface> s =
new gfxSharedImageSurface(aSize, aFormat, shmem);
if (s->CairoStatus() != 0) {
aAllocator->DeallocShmem(shmem);
return nullptr;
}
s->WriteShmemInfo();
return s.forget();
}
Shmem mShmem;
// Calling these is very bad, disallow it
gfxSharedImageSurface(const gfxSharedImageSurface&);
gfxSharedImageSurface& operator=(const gfxSharedImageSurface&);
};
#endif /* GFX_SHARED_IMAGESURFACE_H */