Implement Pepper PPB_VideoDecoder interface.

content/renderer/pepper/pepper_video_decoder_host.h

+// Copyright (c) 2014 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.
+
+#ifndef CONTENT_RENDERER_PEPPER_PEPPER_VIDEO_DECODER_HOST_H_
+#define CONTENT_RENDERER_PEPPER_PEPPER_VIDEO_DECODER_HOST_H_
+
+#include <map>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/containers/hash_tables.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/scoped_vector.h"
+#include "content/common/content_export.h"
+#include "gpu/command_buffer/common/mailbox.h"
+#include "media/video/video_decode_accelerator.h"
+#include "ppapi/c/pp_codecs.h"
+#include "ppapi/host/host_message_context.h"
+#include "ppapi/host/resource_host.h"
+#include "ppapi/proxy/resource_message_params.h"
+// For limits on shm buffer size and number.
+#include "ppapi/proxy/video_decoder_resource.h"

[dmichael (off chromium), 2014/05/20 22:40:38]

Should this go in the body?

[bbudge, 2014/05/22 18:34:55]

Removed this.

+
+namespace base {
+class SharedMemory;
+}
+
+namespace content {
+
+class PPB_Graphics3D_Impl;
+class RendererPpapiHost;
+class RenderViewImpl;
+
+class CONTENT_EXPORT PepperVideoDecoderHost
+    : public ppapi::host::ResourceHost,
+      public media::VideoDecodeAccelerator::Client {
+ public:
+  PepperVideoDecoderHost(RendererPpapiHost* host,
+                         PP_Instance instance,
+                         PP_Resource resource);
+  virtual ~PepperVideoDecoderHost();
+
+ private:
+  struct PendingDecode {
+    PendingDecode(uint32_t shm_id,
+                  const ppapi::host::ReplyMessageContext& reply_context);
+    ~PendingDecode();
+
+    uint32_t shm_id;
+    ppapi::host::ReplyMessageContext reply_context;
+  };
+
+  virtual int32_t OnResourceMessageReceived(
+      const IPC::Message& msg,
+      ppapi::host::HostMessageContext* context) OVERRIDE;
+
+  // media::VideoDecodeAccelerator::Client implementation.
+  virtual void ProvidePictureBuffers(uint32 requested_num_of_buffers,
+                                     const gfx::Size& dimensions,
+                                     uint32 texture_target) OVERRIDE;
+  virtual void DismissPictureBuffer(int32 picture_buffer_id) OVERRIDE;
+  virtual void PictureReady(const media::Picture& picture) OVERRIDE;
+  virtual void NotifyError(media::VideoDecodeAccelerator::Error error) OVERRIDE;
+  virtual void NotifyFlushDone() OVERRIDE;
+  virtual void NotifyEndOfBitstreamBuffer(int32 bitstream_buffer_id) OVERRIDE;
+  virtual void NotifyResetDone() OVERRIDE;
+
+  int32_t OnHostMsgInitialize(ppapi::host::HostMessageContext* context,
+                              const ppapi::HostResource& graphics_context,
+                              PP_VideoProfile profile,
+                              bool allow_software_fallback);
+  int32_t OnHostMsgGetShm(ppapi::host::HostMessageContext* context,
+                          uint32_t size,
+                          uint32_t pending_shm_id);
+  int32_t OnHostMsgAssignTextures(ppapi::host::HostMessageContext* context,
+                                  const PP_Size& size,
+                                  const std::vector<uint32_t>& texture_ids);
+  int32_t OnHostMsgDecode(ppapi::host::HostMessageContext* context,
+                          uint32_t shm_id,
+                          uint32_t size);
+  int32_t OnHostMsgRecyclePicture(ppapi::host::HostMessageContext* context,
+                                  uint32_t picture_id);
+  int32_t OnHostMsgFlush(ppapi::host::HostMessageContext* context);
+  int32_t OnHostMsgReset(ppapi::host::HostMessageContext* context);
+
+  void RequestTextures(uint32 num_textures,
+                       const gfx::Size& dimensions,
+                       uint32 texture_target);
+
+  // Non-owning pointer.
+  RendererPpapiHost* renderer_ppapi_host_;
+
+  scoped_ptr<media::VideoDecodeAccelerator> decoder_;
+
+  scoped_refptr<PPB_Graphics3D_Impl> graphics3d_;
+  ScopedVector<base::SharedMemory> shm_buffers_;
+
+  // Tracks buffers that are in use by the decoder.
+  std::vector<uint8_t> shm_buffer_busy_;

[dmichael (off chromium), 2014/05/20 22:40:38]

Why not std::vector<bool>? Better yet, can't you just check to see if the id
exists in pending_decodes_?

[bbudge, 2014/05/22 18:34:55]

I was avoiding vector<bool> because it is slightly hazardous:
http://isocpp.org/blog/2012/11/on-vectorbool
http://stackoverflow.com/questions/670308/alternative-to-vectorbool

In this case I think it would be OK though.

The keys in pending_decodes_ are decode numbers, not shm_ids, so I would have to
iterate through the map values. I was trying to avoid that, even though the map
is small now.

+  // Unique id for Decode calls.
+  uint32_t next_decode_id_;
+  // Maps decode_id to PendingDecode info.
+  typedef base::hash_map<uint32_t, PendingDecode> PendingDecodeMap;
+  PendingDecodeMap pending_decodes_;
+
+  ppapi::host::ReplyMessageContext flush_reply_context_;
+  ppapi::host::ReplyMessageContext reset_reply_context_;
+
+  bool initialized_;
+
+  DISALLOW_COPY_AND_ASSIGN(PepperVideoDecoderHost);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_PEPPER_PEPPER_VIDEO_DECODER_HOST_H_