FakeVideoCaptureDevice: add support for capturing into Dma-Bufs using VGEM in CrOs

content/browser/renderer_host/media/video_capture_buffer_pool.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/renderer_host/media/video_capture_buffer_pool.h"
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/stl_util.h"
 #include "content/browser/gpu/browser_gpu_memory_buffer_manager.h"
@@ skipping 23 matching lines @@
       return format_pair.frame_format;
   }
   LOG(ERROR) << "Unsupported VideoPixelFormat "
              << media::VideoCaptureFormat::PixelFormatToString(pixel_format);
   return VideoFrame::UNKNOWN;
 }
 
 // A simple holder of a memory-backed buffer and accesors to it.
 class SimpleBufferHandle final : public VideoCaptureBufferPool::BufferHandle {
  public:
-  SimpleBufferHandle(void* data, size_t size) : data_(data), size_(size) {}
+  SimpleBufferHandle(const base::SharedMemory& shared_memory)
+      : shared_memory_(shared_memory),
+        data_(shared_memory.memory()),
+        size_(shared_memory.mapped_size()) {}
   ~SimpleBufferHandle() override {}
 
   size_t size() const override { return size_; }
   void* data() override { return data_; }
   gfx::GpuMemoryBufferType GetType() override {
     return gfx::SHARED_MEMORY_BUFFER;
   }
   ClientBuffer AsClientBuffer() override { return nullptr; }
+  base::PlatformFile AsPlatformFile() override {
+#if defined(OS_POSIX)
+    return shared_memory_.handle().fd;
+#else
+    return shared_memory_.handle();
+#endif
+  }
 
  private:
+  const base::SharedMemory& shared_memory_;
   void* const data_;
   const size_t size_;
 };
 
 // A holder of a GpuMemoryBuffer-backed buffer, Map()ed on ctor and Unmap()ed on
 // dtor. Holds a weak reference to its GpuMemoryBuffer.
 // TODO(mcasas) Map()ed on ctor, or on first use?
 class GpuMemoryBufferBufferHandle
     final : public VideoCaptureBufferPool::BufferHandle {
  public:
   GpuMemoryBufferBufferHandle(gfx::GpuMemoryBuffer* gmb, size_t size)
       : gmb_(gmb),
         data_(new void* [GpuMemoryBufferImpl::
                              NumberOfPlanesForGpuMemoryBufferFormat(
                                  gmb_->GetFormat())]),
         size_(size) {
     DCHECK(gmb && !gmb_->IsMapped());
-    gmb_->Map(data_.get());
+    if (gmb_->GetHandle().type == gfx::SHARED_MEMORY_BUFFER)
+      gmb_->Map(data_.get());
   }
   ~GpuMemoryBufferBufferHandle() override { gmb_->Unmap(); }
 
   size_t size() const override { return size_; }
   void* data() override { return data_[0]; }
   gfx::GpuMemoryBufferType GetType() override {
     return gmb_->GetHandle().type;
   }
   ClientBuffer AsClientBuffer() override { return gmb_->AsClientBuffer(); }
+  base::PlatformFile AsPlatformFile() override {
+    NOTIMPLEMENTED();
+    return base::PlatformFile();
+  }
 
  private:
   gfx::GpuMemoryBuffer* const gmb_;
   scoped_ptr<void*[]> data_;
   const size_t size_;
 };
 
 // Tracker specifics for SharedMemory.
 class VideoCaptureBufferPool::SharedMemTracker final : public Tracker {
  public:
   SharedMemTracker();
   bool Init(VideoFrame::Format format, const gfx::Size& dimensions) override;
 
   size_t mapped_size() const override { return shared_memory_.mapped_size(); }
 
   scoped_ptr<BufferHandle> GetBufferHandle() override {
-    return make_scoped_ptr(
-        new SimpleBufferHandle(shared_memory_.memory(), mapped_size()));
+    return make_scoped_ptr(new SimpleBufferHandle(shared_memory_));
   }
 
   bool ShareToProcess(base::ProcessHandle process_handle,
                       base::SharedMemoryHandle* new_handle) override {
     return shared_memory_.ShareToProcess(process_handle, new_handle);
   }
 
  private:
   // The memory created to be shared with renderer processes.
   base::SharedMemory shared_memory_;
@@ skipping 238 matching lines @@
   return buffer_id;
 }
 
 VideoCaptureBufferPool::Tracker* VideoCaptureBufferPool::GetTracker(
     int buffer_id) {
   TrackerMap::const_iterator it = trackers_.find(buffer_id);
   return (it == trackers_.end()) ? NULL : it->second;
 }
 
 }  // namespace content