Data type conversion between extensions API and Cast API

chrome/renderer/extensions/webrtc_native_handler.cc

 // Copyright 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 "chrome/renderer/extensions/webrtc_native_handler.h"
 
+#include <functional>
+
 #include "base/logging.h"
 #include "chrome/common/extensions/api/webrtc_cast_send_transport.h"
 #include "chrome/common/extensions/api/webrtc_cast_udp_transport.h"
 #include "chrome/renderer/extensions/chrome_v8_context.h"
 #include "chrome/renderer/media/cast_send_transport.h"
 #include "chrome/renderer/media/cast_session.h"
 #include "chrome/renderer/media/cast_udp_transport.h"
 #include "content/public/renderer/v8_value_converter.h"
 #include "net/base/host_port_pair.h"
 
 using content::V8ValueConverter;
 
 // Extension types.
+using extensions::api::webrtc_cast_send_transport::CodecSpecificParams;
 using extensions::api::webrtc_cast_send_transport::RtpCaps;
 using extensions::api::webrtc_cast_send_transport::RtpParams;
 using extensions::api::webrtc_cast_send_transport::RtpPayloadParams;
 using extensions::api::webrtc_cast_udp_transport::CreateInfo;
 using extensions::api::webrtc_cast_udp_transport::UdpParams;
 
 namespace extensions {
 
 namespace {
 const char kSendTransportNotFound[] = "The send transport cannot be found";
 const char kUdpTransportNotFound[] = "The UDP transport cannot be found";
 const char kInvalidUdpParams[] = "Invalid UDP params";
 const char kInvalidRtpCaps[] = "Invalid value for RTP caps";
 const char kInvalidRtpParams[] = "Invalid value for RTP params";
 const char kUnableToConvertArgs[] = "Unable to convert arguments";
-const char kUnableToConvertCaps[] = "Unable to convert caps";
 const char kUnableToConvertParams[] = "Unable to convert params";
 
 // These helper methods are used to convert between Extension API
 // types and Cast types.
-bool ToCastRtpCaps(const RtpCaps& ext_caps, CastRtpCaps* cast_caps) {
-  NOTIMPLEMENTED();
-  return true;
+void ToCastCodecSpecificParams(const CodecSpecificParams& ext_params,
+                               CastCodecSpecificParams* cast_params) {
+  cast_params->key = ext_params.key;
+  cast_params->value = ext_params.value;
 }
 
-bool FromCastRtpCaps(const CastRtpCaps& cast_caps, RtpCaps* ext_caps) {
-  NOTIMPLEMENTED();
-  return true;
+void FromCastCodecSpecificParams(const CastCodecSpecificParams& cast_params,
+                                 CodecSpecificParams* ext_params) {
+  ext_params->key = cast_params.key;
+  ext_params->value = cast_params.value;
 }
 
-bool ToCastRtpParams(const RtpParams& ext_params, CastRtpParams* cast_params) {
-  NOTIMPLEMENTED();
-  return true;
+void ToCastRtpPayloadParams(const RtpPayloadParams& ext_params,
+                            CastRtpPayloadParams* cast_params) {
+  cast_params->payload_type = ext_params.payload_type;
+  cast_params->codec_name = ext_params.codec_name;
+  cast_params->ssrc = ext_params.ssrc ? *ext_params.ssrc : 0;
+  cast_params->clock_rate = ext_params.clock_rate ? *ext_params.clock_rate : 0;
+  cast_params->min_bitrate =
+      ext_params.min_bitrate ? *ext_params.min_bitrate : 0;
+  cast_params->max_bitrate =
+      ext_params.max_bitrate ? *ext_params.max_bitrate : 0;
+  cast_params->channels = ext_params.channels ? *ext_params.channels : 0;
+  cast_params->width = ext_params.width ? *ext_params.width : 0;
+  cast_params->height = ext_params.height ? *ext_params.height : 0;
+  for (size_t i = 0; i < ext_params.codec_specific_params.size(); ++i) {
+    CastCodecSpecificParams cast_codec_params;
+    ToCastCodecSpecificParams(*ext_params.codec_specific_params[i],
+                              &cast_codec_params);
+    cast_params->codec_specific_params.push_back(cast_codec_params);

[not at google - send to devlin, 2013/11/01 22:45:34]

I'm not confident in C++ to know whether this is a worthwhile optimisation, but
it does seem like you'll end up doing a bit of unnecessary copying here. This
might work:

cast_params->codec_specific_params.resize(
    ext_params.code_specific_params.size());
for (size_t i = 0; i < ext_params.code_specific_params.size();++i) {
  ToCastCodecSpecificParams(*ext_params.code_specific_params[i],
                            &code_specific_params[i])
}

[Alpha Left Google, 2013/11/06 00:15:56]

Those are fairly small data structures so copying them doesn't have a large
overhead.

+  }
 }
 
-bool FromCastRtpParams(const CastRtpParams& cast_params,
+void FromCastRtpPayloadParams(const CastRtpPayloadParams& cast_params,
+                              RtpPayloadParams* ext_params) {
+  ext_params->payload_type = cast_params.payload_type;
+  ext_params->codec_name = cast_params.codec_name;
+  if (cast_params.ssrc) {
+    ext_params->ssrc.reset(new int);
+    *ext_params->ssrc = cast_params.ssrc;

[not at google - send to devlin, 2013/11/01 22:45:34]

why not just ext_params->ssrc.reset(new int(cast_params.ssrc))?

[Alpha Left Google, 2013/11/06 00:15:56]

Done.

+  }
+  if (cast_params.clock_rate) {
+    ext_params->clock_rate.reset(new int);
+    *ext_params->clock_rate = cast_params.clock_rate;
+  }
+  if (cast_params.min_bitrate) {
+    ext_params->min_bitrate.reset(new int);
+    *ext_params->min_bitrate = cast_params.min_bitrate;
+  }
+  if (cast_params.max_bitrate) {
+    ext_params->max_bitrate.reset(new int);
+    *ext_params->max_bitrate = cast_params.max_bitrate;
+  }
+  if (cast_params.channels) {
+    ext_params->channels.reset(new int);
+    *ext_params->channels = cast_params.channels;
+  }
+  if (cast_params.width) {
+    ext_params->width.reset(new int);
+    *ext_params->width = cast_params.width;
+  }
+  if (cast_params.height) {
+    ext_params->height.reset(new int);
+    *ext_params->height = cast_params.height;
+  }
+  for (size_t i = 0; i < cast_params.codec_specific_params.size(); ++i) {
+    linked_ptr<CodecSpecificParams> ext_codec_params(
+        new CodecSpecificParams());
+    FromCastCodecSpecificParams(cast_params.codec_specific_params[i],
+                                ext_codec_params.get());
+    ext_params->codec_specific_params.push_back(ext_codec_params);
+  }
+}
+
+void ToCastRtpCaps(const RtpCaps& ext_caps, CastRtpCaps* cast_caps) {
+  std::copy(ext_caps.rtcp_features.begin(), ext_caps.rtcp_features.end(),
+            cast_caps->rtcp_features.begin());
+  std::copy(ext_caps.fec_mechanisms.begin(), ext_caps.fec_mechanisms.end(),
+            cast_caps->fec_mechanisms.begin());
+  for (size_t i = 0; i < ext_caps.payloads.size(); ++i) {
+    CastRtpPayloadParams cast_payload_params;
+    ToCastRtpPayloadParams(*ext_caps.payloads[i], &cast_payload_params);
+    cast_caps->payloads.push_back(cast_payload_params);
+  }
+}
+
+void FromCastRtpCaps(const CastRtpCaps& cast_caps, RtpCaps* ext_caps) {
+  std::copy(cast_caps.rtcp_features.begin(), cast_caps.rtcp_features.end(),
+            ext_caps->rtcp_features.begin());
+  std::copy(cast_caps.fec_mechanisms.begin(), cast_caps.fec_mechanisms.end(),
+            ext_caps->fec_mechanisms.begin());
+  for (size_t i = 0; i < cast_caps.payloads.size(); ++i) {
+    linked_ptr<RtpPayloadParams> ext_payload_params(new RtpPayloadParams());
+    FromCastRtpPayloadParams(cast_caps.payloads[i], ext_payload_params.get());
+    ext_caps->payloads.push_back(ext_payload_params);
+  }
+}
+
+void ToCastRtpParams(const RtpParams& ext_params, CastRtpParams* cast_params) {
+  std::copy(ext_params.rtcp_features.begin(), ext_params.rtcp_features.end(),
+            cast_params->rtcp_features.begin());
+  std::copy(ext_params.fec_mechanisms.begin(), ext_params.fec_mechanisms.end(),
+            cast_params->fec_mechanisms.begin());
+  for (size_t i = 0; i < ext_params.payloads.size(); ++i) {
+    CastRtpPayloadParams cast_payload_params;
+    ToCastRtpPayloadParams(*ext_params.payloads[i], &cast_payload_params);
+    cast_params->payloads.push_back(cast_payload_params);
+  }
+}
+
+void FromCastRtpParams(const CastRtpParams& cast_params,
                        RtpParams* ext_params) {
-  NOTIMPLEMENTED();
-  return true;
+  std::copy(cast_params.rtcp_features.begin(), cast_params.rtcp_features.end(),
+            ext_params->rtcp_features.begin());
+  std::copy(cast_params.fec_mechanisms.begin(),
+            cast_params.fec_mechanisms.end(),
+            ext_params->fec_mechanisms.begin());
+  for (size_t i = 0; i < cast_params.payloads.size(); ++i) {
+    linked_ptr<RtpPayloadParams> ext_payload_params(new RtpPayloadParams());
+    FromCastRtpPayloadParams(cast_params.payloads[i],
+                             ext_payload_params.get());
+    ext_params->payloads.push_back(ext_payload_params);
+  }
 }
 
 }  // namespace
 
 WebRtcNativeHandler::WebRtcNativeHandler(ChromeV8Context* context)
     : ObjectBackedNativeHandler(context),
       last_transport_id_(0) {
   RouteFunction("CreateCastSendTransport",
       base::Bind(&WebRtcNativeHandler::CreateCastSendTransport,
                  base::Unretained(this)));
@@ skipping 86 matching lines @@
   }
   scoped_ptr<RtpCaps> remote_caps =
       RtpCaps::FromValue(*remote_caps_value);
   if (!remote_caps) {
     v8::ThrowException(v8::Exception::TypeError(v8::String::New(
         kInvalidRtpCaps)));
     return;
   }
 
   CastRtpCaps cast_remote_caps;
-  if (!ToCastRtpCaps(*remote_caps, &cast_remote_caps)) {
-    v8::ThrowException(v8::Exception::TypeError(v8::String::New(
-        kUnableToConvertCaps)));
-    return;
-  }
+  ToCastRtpCaps(*remote_caps, &cast_remote_caps);
   CastRtpParams cast_params = transport->CreateParams(cast_remote_caps);
   RtpParams params;
-  if (!FromCastRtpParams(cast_params, &params)) {
-    v8::ThrowException(v8::Exception::TypeError(v8::String::New(
-        kUnableToConvertParams)));
-    return;
-  }
+  FromCastRtpParams(cast_params, &params);
 
   scoped_ptr<base::DictionaryValue> params_value = params.ToValue();
   v8::Handle<v8::Value> params_v8 = converter->ToV8Value(
       params_value.get(), context()->v8_context());
   context()->CallFunction(v8::Handle<v8::Function>::Cast(args[2]), 1,
                           &params_v8);
 }
 
 void WebRtcNativeHandler::GetCapsCastSendTransport(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
   CHECK_EQ(2, args.Length());
   CHECK(args[0]->IsInt32());
   CHECK(args[1]->IsFunction());
 
   const int transport_id = args[0]->ToInt32()->Value();
   CastSendTransport* transport = GetSendTransportOrThrow(transport_id);
   if (!transport)
     return;
 
   CastRtpCaps cast_caps = transport->GetCaps();
   RtpCaps caps;
-  if (!FromCastRtpCaps(cast_caps, &caps)) {
-    v8::ThrowException(v8::Exception::TypeError(v8::String::New(
-        kUnableToConvertCaps)));
-    return;
-  }
+  FromCastRtpCaps(cast_caps, &caps);
 
   scoped_ptr<base::DictionaryValue> caps_value = caps.ToValue();
   scoped_ptr<V8ValueConverter> converter(V8ValueConverter::create());
   v8::Handle<v8::Value> caps_v8 = converter->ToV8Value(
       caps_value.get(), context()->v8_context());
   context()->CallFunction(v8::Handle<v8::Function>::Cast(args[1]), 1,
                           &caps_v8);
 }
 
 void WebRtcNativeHandler::StartCastSendTransport(
@@ skipping 16 matching lines @@
     return;
   }
   scoped_ptr<RtpParams> params = RtpParams::FromValue(*params_value);
   if (!params) {
     v8::ThrowException(v8::Exception::TypeError(v8::String::New(
         kInvalidRtpParams)));
     return;
   }
 
   CastRtpCaps cast_params;
-  if (!ToCastRtpParams(*params, &cast_params)) {
-    v8::ThrowException(v8::Exception::TypeError(v8::String::New(
-        kUnableToConvertParams)));
-    return;
-  }
+  ToCastRtpParams(*params, &cast_params);
   transport->Start(cast_params);
 }
 
 void WebRtcNativeHandler::StopCastSendTransport(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
   CHECK_EQ(1, args.Length());
   CHECK(args[0]->IsInt32());
 
   const int transport_id = args[0]->ToInt32()->Value();
   CastSendTransport* transport = GetSendTransportOrThrow(transport_id);
@@ skipping 88 matching lines @@
   UdpTransportMap::const_iterator iter = udp_transport_map_.find(
       transport_id);
   if (iter != udp_transport_map_.end())
     return iter->second.get();
   v8::ThrowException(v8::Exception::RangeError(v8::String::New(
       kUdpTransportNotFound)));
   return NULL;
 }
 
 }  // namespace extensions