Add initialization callback support for Video Decoder PPAPI.

ppapi/c/dev/ppb_video_decoder_dev.h

 /* Copyright (c) 2011 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 PPAPI_C_DEV_PPB_VIDEO_DECODER_DEV_H_
 #define PPAPI_C_DEV_PPB_VIDEO_DECODER_DEV_H_
 
 #include "ppapi/c/dev/pp_video_dev.h"
 #include "ppapi/c/pp_completion_callback.h"
 #include "ppapi/c/pp_var.h"
 
-#define PPB_VIDEODECODER_DEV_INTERFACE_0_7 "PPB_VideoDecoder(Dev);0.7"
-#define PPB_VIDEODECODER_DEV_INTERFACE PPB_VIDEODECODER_DEV_INTERFACE_0_7
+#define PPB_VIDEODECODER_DEV_INTERFACE_0_8 "PPB_VideoDecoder(Dev);0.8"
+#define PPB_VIDEODECODER_DEV_INTERFACE PPB_VIDEODECODER_DEV_INTERFACE_0_8
 
 // Video decoder interface.
 //
 // Basic usage:
 //   1. Use GetConfigs() to query potential configurations. Configuration
 //   information includes:
 //     a. Bitstream format.
 //     b. Output picture format.
 //     c. Output picture buffer storage type.
 //   2. Select configuration that suits you and Create() the decoder with the
@@ skipping 100 matching lines @@
   // Creates a video decoder with requested |decoder_config|.
   // |input_format| in |decoder_config| specifies the format of input access
   // unit, with PP_VIDEOKEY_CODECID and PP_VIDEOKEY_PAYLOADFORMAT required.
   // Plugin has the option to specify codec profile/level and other
   // information such as PP_VIDEOKEY_ACCELERATION, to let browser choose
   // the most appropriate decoder.
   //
   // Parameters:
   //   |instance| pointer to the plugin instance.
   //   |dec_config| the configuration which to use to initialize the decoder.
+  //   |callback| called after initialize is complete.
   //
   // The created decoder is returned as PP_Resource. NULL means failure.
   PP_Resource (*Create)(PP_Instance instance,

[darin (slow to review), 2011/05/31 21:40:47]

This method is misusing PP_CompletionCallback.  Any function that takes a
PP_CompletionCallback MUST return int32_t, and it must return
PP_OK_COMPLETIONPENDING when it will complete its work asynchronously or PP_OK /
some error code if the completion callback will not run.

In this case, it means that you need to break out a separate "init" method, just
like PPB_URLLoader::Open.

It looks like you already have an Init method under the hood, so this change
should be trivial.

-                        PP_VideoConfigElement* dec_config);
+                        PP_VideoConfigElement* dec_config,
+                        struct PP_CompletionCallback callback);
 
   // Tests whether |resource| is a video decoder created through Create
   // function of this interface.
   //
   // Parameters:
   //   |resource| is handle to resource to test.
   //
   // Returns true if is a video decoder, false otherwise.
   PP_Bool (*IsVideoDecoder)(PP_Resource resource);
 
   // Dispatches bitstream buffer to the decoder. This is asynchronous and
   // non-blocking function.
   //
   // Parameters:
   //   |video_decoder| is the previously created handle to the decoder instance.
   //   |bitstream_buffer| is the bitstream buffer that contains the input data.
   //   |callback| will be called when |bitstream_buffer| has been processed by
   //   the decoder.
   //
   // Returns PP_TRUE on decoder successfully accepting buffer, PP_FALSE
   // otherwise.
   PP_Bool (*Decode)(PP_Resource video_decoder,

[darin (slow to review), 2011/05/31 21:40:47]

this method signature is also wrong.  it should return int32_t.

                     struct PP_VideoBitstreamBuffer_Dev* bitstream_buffer,
                     struct PP_CompletionCallback callback);
 
   // Provides the decoder with picture buffers for video decoding.
   // AssignGLESBuffers provides texture-backed buffers, whereas
   // AssignSysmemBuffers provides system memory-backed buffers.
   //
   // This function should be called when decoder has issued the
   // ProvidePictureBuffers callback to the plugin with buffer requirements.
   //
@@ skipping 50 matching lines @@
   // the callbacks implemented by the plug-in. Once done with flushing, the
   // decode will call the |callback|.
   //
   // Parameters:
   //   |video_decoder| is the previously created handle to the decoder instance.
   //   |callback| is one-time callback that will be called once the flushing
   //   request has been completed.
   //
   // Returns PP_TRUE on acceptance of flush request and PP_FALSE if request to
   // flush is rejected by the decoder.
   PP_Bool (*Flush)(PP_Resource video_decoder,

[darin (slow to review), 2011/05/31 21:40:47]

ditto

                    struct PP_CompletionCallback callback);
 
   // Dispatches abortion request to the decoder to abort decoding as soon as
   // possible and will not output anything or generate new callbacks. |callback|
   // will be called as soon as abortion has been finished. After abortion all
   // buffers can be considered dismissed even when there has not been callbacks
   // to dismiss them.
   //
   // Parameters:
   //   |video_decoder| is the previously created handle to the decoder instance.
   //   |callback| is one-time callback that will be called once the abortion
   //   request has been completed.
   //
   // Returns PP_TRUE on acceptance of abort request and PP_FALSE if request to
   // abort is rejected by the decoder.
   PP_Bool (*Abort)(PP_Resource video_decoder,

[darin (slow to review), 2011/05/31 21:40:47]

ditto

                    struct PP_CompletionCallback callback);
 };
 
 #endif  /* PPAPI_C_DEV_PPB_VIDEO_DECODER_DEV_H_ */