1 files changed, 333 insertions, 0 deletions
diff --git a/gfx/gl/SharedSurface.h b/gfx/gl/SharedSurface.h
new file mode 100644
index 000000000..0cd21d1b7
--- /dev/null
+++ b/gfx/gl/SharedSurface.h
@@ -0,0 +1,333 @@
+/* -*- Mode: c++; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 40; -*- */
+/* 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/. */
+
+/* SharedSurface abstracts an actual surface (can be a GL texture, but
+ * not necessarily) that handles sharing.
+ * Its specializations are:
+ *     SharedSurface_Basic (client-side bitmap, does readback)
+ *     SharedSurface_GLTexture
+ *     SharedSurface_EGLImage
+ *     SharedSurface_ANGLEShareHandle
+ */
+
+#ifndef SHARED_SURFACE_H_
+#define SHARED_SURFACE_H_
+
+#include <queue>
+#include <set>
+#include <stdint.h>
+
+#include "GLContextTypes.h"
+#include "GLDefs.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/gfx/Point.h"
+#include "mozilla/Mutex.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/WeakPtr.h"
+#include "ScopedGLHelpers.h"
+#include "SurfaceTypes.h"
+
+class nsIThread;
+
+namespace mozilla {
+namespace gfx {
+class DataSourceSurface;
+class DrawTarget;
+} // namespace gfx
+
+namespace layers {
+class LayersIPCChannel;
+class SharedSurfaceTextureClient;
+enum class TextureFlags : uint32_t;
+class SurfaceDescriptor;
+class TextureClient;
+} // namespace layers
+
+namespace gl {
+
+class GLContext;
+class SurfaceFactory;
+class ShSurfHandle;
+
+class SharedSurface
+{
+public:
+    static void ProdCopy(SharedSurface* src, SharedSurface* dest,
+                         SurfaceFactory* factory);
+
+    const SharedSurfaceType mType;
+    const AttachmentType mAttachType;
+    const WeakPtr<GLContext> mGL;
+    const gfx::IntSize mSize;
+    const bool mHasAlpha;
+    const bool mCanRecycle;
+protected:
+    bool mIsLocked;
+    bool mIsProducerAcquired;
+#ifdef DEBUG
+    nsIThread* const mOwningThread;
+#endif
+
+    SharedSurface(SharedSurfaceType type,
+                  AttachmentType attachType,
+                  GLContext* gl,
+                  const gfx::IntSize& size,
+                  bool hasAlpha,
+                  bool canRecycle);
+
+public:
+    virtual ~SharedSurface() {
+    }
+
+    // Specifies to the TextureClient any flags which
+    // are required by the SharedSurface backend.
+    virtual layers::TextureFlags GetTextureFlags() const;
+
+    bool IsLocked() const { return mIsLocked; }
+    bool IsProducerAcquired() const { return mIsProducerAcquired; }
+
+    // This locks the SharedSurface as the production buffer for the context.
+    // This is needed by backends which use PBuffers and/or EGLSurfaces.
+    void LockProd();
+
+    // Unlocking is harmless if we're already unlocked.
+    void UnlockProd();
+
+protected:
+    virtual void LockProdImpl() = 0;
+    virtual void UnlockProdImpl() = 0;
+
+    virtual void ProducerAcquireImpl() = 0;
+    virtual void ProducerReleaseImpl() = 0;
+    virtual void ProducerReadAcquireImpl() { ProducerAcquireImpl(); }
+    virtual void ProducerReadReleaseImpl() { ProducerReleaseImpl(); }
+
+public:
+    void ProducerAcquire() {
+        MOZ_ASSERT(!mIsProducerAcquired);
+        ProducerAcquireImpl();
+        mIsProducerAcquired = true;
+    }
+    void ProducerRelease() {
+        MOZ_ASSERT(mIsProducerAcquired);
+        ProducerReleaseImpl();
+        mIsProducerAcquired = false;
+    }
+    void ProducerReadAcquire() {
+        MOZ_ASSERT(!mIsProducerAcquired);
+        ProducerReadAcquireImpl();
+        mIsProducerAcquired = true;
+    }
+    void ProducerReadRelease() {
+        MOZ_ASSERT(mIsProducerAcquired);
+        ProducerReadReleaseImpl();
+        mIsProducerAcquired = false;
+    }
+
+    // This function waits until the buffer is no longer being used.
+    // To optimize the performance, some implementaions recycle SharedSurfaces
+    // even when its buffer is still being used.
+    virtual void WaitForBufferOwnership() {}
+
+    // For use when AttachType is correct.
+    virtual GLenum ProdTextureTarget() const {
+        MOZ_ASSERT(mAttachType == AttachmentType::GLTexture);
+        return LOCAL_GL_TEXTURE_2D;
+    }
+
+    virtual GLuint ProdTexture() {
+        MOZ_ASSERT(mAttachType == AttachmentType::GLTexture);
+        MOZ_CRASH("GFX: Did you forget to override this function?");
+    }
+
+    virtual GLuint ProdRenderbuffer() {
+        MOZ_ASSERT(mAttachType == AttachmentType::GLRenderbuffer);
+        MOZ_CRASH("GFX: Did you forget to override this function?");
+    }
+
+    virtual bool CopyTexImage2D(GLenum target, GLint level, GLenum internalformat, GLint x,
+                                GLint y, GLsizei width, GLsizei height, GLint border)
+    {
+        return false;
+    }
+
+    virtual bool ReadPixels(GLint x, GLint y,
+                            GLsizei width, GLsizei height,
+                            GLenum format, GLenum type,
+                            GLvoid* pixels)
+    {
+        return false;
+    }
+
+    virtual bool NeedsIndirectReads() const {
+        return false;
+    }
+
+    virtual bool ToSurfaceDescriptor(layers::SurfaceDescriptor* const out_descriptor) = 0;
+
+    virtual bool ReadbackBySharedHandle(gfx::DataSourceSurface* out_surface) {
+        return false;
+    }
+};
+
+template<typename T>
+class RefSet
+{
+    std::set<T*> mSet;
+
+public:
+    ~RefSet() {
+        clear();
+    }
+
+    auto begin() -> decltype(mSet.begin()) {
+        return mSet.begin();
+    }
+
+    void clear() {
+        for (auto itr = mSet.begin(); itr != mSet.end(); ++itr) {
+            (*itr)->Release();
+        }
+        mSet.clear();
+    }
+
+    bool empty() const {
+        return mSet.empty();
+    }
+
+    bool insert(T* x) {
+        if (mSet.insert(x).second) {
+            x->AddRef();
+            return true;
+        }
+
+        return false;
+    }
+
+    bool erase(T* x) {
+        if (mSet.erase(x)) {
+            x->Release();
+            return true;
+        }
+
+        return false;
+    }
+};
+
+template<typename T>
+class RefQueue
+{
+    std::queue<T*> mQueue;
+
+public:
+    ~RefQueue() {
+        clear();
+    }
+
+    void clear() {
+        while (!empty()) {
+            pop();
+        }
+    }
+
+    bool empty() const {
+        return mQueue.empty();
+    }
+
+    size_t size() const {
+        return mQueue.size();
+    }
+
+    void push(T* x) {
+        mQueue.push(x);
+        x->AddRef();
+    }
+
+    T* front() const {
+        return mQueue.front();
+    }
+
+    void pop() {
+        T* x = mQueue.front();
+        x->Release();
+        mQueue.pop();
+    }
+};
+
+class SurfaceFactory : public SupportsWeakPtr<SurfaceFactory>
+{
+public:
+    // Should use the VIRTUAL version, but it's currently incompatible
+    // with SupportsWeakPtr. (bug 1049278)
+    MOZ_DECLARE_WEAKREFERENCE_TYPENAME(SurfaceFactory)
+
+    const SharedSurfaceType mType;
+    GLContext* const mGL;
+    const SurfaceCaps mCaps;
+    const RefPtr<layers::LayersIPCChannel> mAllocator;
+    const layers::TextureFlags mFlags;
+    const GLFormats mFormats;
+    Mutex mMutex;
+protected:
+    SurfaceCaps mDrawCaps;
+    SurfaceCaps mReadCaps;
+    RefQueue<layers::SharedSurfaceTextureClient> mRecycleFreePool;
+    RefSet<layers::SharedSurfaceTextureClient> mRecycleTotalPool;
+
+    SurfaceFactory(SharedSurfaceType type, GLContext* gl, const SurfaceCaps& caps,
+                   const RefPtr<layers::LayersIPCChannel>& allocator,
+                   const layers::TextureFlags& flags);
+
+public:
+    virtual ~SurfaceFactory();
+
+    const SurfaceCaps& DrawCaps() const {
+        return mDrawCaps;
+    }
+
+    const SurfaceCaps& ReadCaps() const {
+        return mReadCaps;
+    }
+
+protected:
+    virtual UniquePtr<SharedSurface> CreateShared(const gfx::IntSize& size) = 0;
+
+    void StartRecycling(layers::SharedSurfaceTextureClient* tc);
+    void SetRecycleCallback(layers::SharedSurfaceTextureClient* tc);
+    void StopRecycling(layers::SharedSurfaceTextureClient* tc);
+
+public:
+    UniquePtr<SharedSurface> NewSharedSurface(const gfx::IntSize& size);
+    //already_AddRefed<ShSurfHandle> NewShSurfHandle(const gfx::IntSize& size);
+    already_AddRefed<layers::SharedSurfaceTextureClient> NewTexClient(const gfx::IntSize& size);
+
+    static void RecycleCallback(layers::TextureClient* tc, void* /*closure*/);
+
+    // Auto-deletes surfs of the wrong type.
+    bool Recycle(layers::SharedSurfaceTextureClient* texClient);
+};
+
+class ScopedReadbackFB
+{
+    GLContext* const mGL;
+    ScopedBindFramebuffer mAutoFB;
+    GLuint mTempFB;
+    GLuint mTempTex;
+    SharedSurface* mSurfToUnlock;
+    SharedSurface* mSurfToLock;
+
+public:
+    explicit ScopedReadbackFB(SharedSurface* src);
+    ~ScopedReadbackFB();
+};
+
+bool ReadbackSharedSurface(SharedSurface* src, gfx::DrawTarget* dst);
+uint32_t ReadPixel(SharedSurface* src);
+
+} // namespace gl
+} // namespace mozilla
+
+#endif // SHARED_SURFACE_H_