[Mojo Video Capture] Simplify media::VideoCaptureDevice::Client:Buffer to a struct

content/browser/renderer_host/media/video_capture_gpu_jpeg_decoder.cc

 // Copyright 2015 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_gpu_jpeg_decoder.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/stringprintf.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/trace_event/trace_event.h"
 #include "build/build_config.h"
 #include "content/browser/gpu/browser_gpu_channel_host_factory.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/common/content_switches.h"
 #include "media/base/video_frame.h"
 #include "media/gpu/ipc/client/gpu_jpeg_decode_accelerator_host.h"
+#include "mojo/public/cpp/system/platform_handle.h"
 
 namespace content {
 
 VideoCaptureGpuJpegDecoder::VideoCaptureGpuJpegDecoder(
     const DecodeDoneCB& decode_done_cb)
     : decode_done_cb_(decode_done_cb),
       next_bitstream_buffer_id_(0),
       in_buffer_id_(media::JpegDecodeAccelerator::kInvalidBitstreamBufferId),
       decoder_status_(INIT_PENDING) {}
 
@@ skipping 41 matching lines @@
   base::AutoLock lock(lock_);
   return decoder_status_;
 }
 
 void VideoCaptureGpuJpegDecoder::DecodeCapturedData(
     const uint8_t* data,
     size_t in_buffer_size,
     const media::VideoCaptureFormat& frame_format,
     base::TimeTicks reference_time,
     base::TimeDelta timestamp,
-    std::unique_ptr<media::VideoCaptureDevice::Client::Buffer> out_buffer) {
+    media::VideoCaptureDevice::Client::Buffer out_buffer) {
   DCHECK(CalledOnValidThread());
   DCHECK(decoder_);
 
   TRACE_EVENT_ASYNC_BEGIN0("jpeg", "VideoCaptureGpuJpegDecoder decoding",
                            next_bitstream_buffer_id_);
   TRACE_EVENT0("jpeg", "VideoCaptureGpuJpegDecoder::DecodeCapturedData");
 
   // TODO(kcwu): enqueue decode requests in case decoding is not fast enough
   // (say, if decoding time is longer than 16ms for 60fps 4k image)
   {
@@ skipping 19 matching lines @@
   }
   memcpy(in_shared_memory_->memory(), data, in_buffer_size);
 
   // No need to lock for |in_buffer_id_| since IsDecoding_Locked() is false.
   in_buffer_id_ = next_bitstream_buffer_id_;
   media::BitstreamBuffer in_buffer(in_buffer_id_, in_shared_memory_->handle(),
                                    in_buffer_size);
   // Mask against 30 bits, to avoid (undefined) wraparound on signed integer.
   next_bitstream_buffer_id_ = (next_bitstream_buffer_id_ + 1) & 0x3FFFFFFF;
 
-#if defined(OS_POSIX) && !defined(OS_MACOSX)
+  // The APIs of |decoder_| and |decode_done_cb_| require us to wrap the
+  // |out_buffer| in a VideoFrame.
   const gfx::Size dimensions = frame_format.frame_size;
-  base::SharedMemoryHandle out_handle = out_buffer->AsPlatformFile();
+  std::unique_ptr<media::VideoCaptureBufferHandle> out_buffer_access =
+      out_buffer.handle_provider()->GetHandleForInProcessAccess();
+  base::SharedMemoryHandle memory_handle;
+  size_t memory_size = 0;
+  bool read_only_flag = false;
+  const MojoResult result = mojo::UnwrapSharedMemoryHandle(
+      out_buffer.handle_provider()->GetHandleForInterProcessTransit(),
+      &memory_handle, &memory_size, &read_only_flag);
+  DCHECK_EQ(MOJO_RESULT_OK, result);
+  DCHECK_GT(memory_size, 0u);
   scoped_refptr<media::VideoFrame> out_frame =
       media::VideoFrame::WrapExternalSharedMemory(
-          media::PIXEL_FORMAT_I420,                   // format
-          dimensions,                                 // coded_size
-          gfx::Rect(dimensions),                      // visible_rect
-          dimensions,                                 // natural_size
-          static_cast<uint8_t*>(out_buffer->data()),  // data
-          out_buffer->mapped_size(),                  // data_size
-          out_handle,                                 // handle
-          0,                                          // shared_memory_offset
-          timestamp);                                 // timestamp
+          media::PIXEL_FORMAT_I420,          // format
+          dimensions,                        // coded_size
+          gfx::Rect(dimensions),             // visible_rect
+          dimensions,                        // natural_size
+          out_buffer_access->data(),         // data
+          out_buffer_access->mapped_size(),  // data_size
+          std::move(memory_handle),          // handle
+          0,                                 // shared_memory_offset
+          timestamp);                        // timestamp
   if (!out_frame) {
     base::AutoLock lock(lock_);
     decoder_status_ = FAILED;
     LOG(ERROR) << "DecodeCapturedData: WrapExternalSharedMemory failed";
     return;
   }
   out_frame->metadata()->SetDouble(media::VideoFrameMetadata::FRAME_RATE,
                                    frame_format.frame_rate);
 
   out_frame->metadata()->SetTimeTicks(media::VideoFrameMetadata::REFERENCE_TIME,
                                       reference_time);
 
   {
     base::AutoLock lock(lock_);
     decode_done_closure_ =
         base::Bind(decode_done_cb_, base::Passed(&out_buffer), out_frame);
   }
   decoder_->Decode(in_buffer, std::move(out_frame));
-#else
-  NOTREACHED();
-#endif
 }
 
 void VideoCaptureGpuJpegDecoder::VideoFrameReady(int32_t bitstream_buffer_id) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   TRACE_EVENT0("jpeg", "VideoCaptureGpuJpegDecoder::VideoFrameReady");
   base::AutoLock lock(lock_);
 
   if (!IsDecoding_Locked()) {
     LOG(ERROR) << "Got decode response while not decoding";
     return;
@@ skipping 81 matching lines @@
   lock_.AssertAcquired();
   return !decode_done_closure_.is_null();
 }
 
 void VideoCaptureGpuJpegDecoder::RecordInitDecodeUMA_Locked() {
   UMA_HISTOGRAM_BOOLEAN("Media.VideoCaptureGpuJpegDecoder.InitDecodeSuccess",
                         decoder_status_ == INIT_PASSED);
 }
 
 }  // namespace content