Implement plugin side of sync EnumerateVideoCaptureDevices

ppapi/proxy/resource_message_test_sink.h

 // Copyright (c) 2012 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_PROXY_RESOURCE_MESSAGE_TEST_SINK_H_
 #define PPAPI_PROXY_RESOURCE_MESSAGE_TEST_SINK_H_
 
 #include "ipc/ipc_test_sink.h"
 
 namespace ppapi {
 namespace proxy {
 
 class ResourceMessageCallParams;
 class ResourceMessageReplyParams;
 
 // Extends IPC::TestSink to add extra capabilities for searching for and
 // decoding resource messages.
 class ResourceMessageTestSink : public IPC::TestSink {
  public:
   ResourceMessageTestSink();
   virtual ~ResourceMessageTestSink();
 
+  // IPC::TestSink.
+  // Overridden to handle sync messages.
+  virtual bool Send(IPC::Message* msg) OVERRIDE;
+
+  // Sets the reply message that will be returned to the next sync message sent.
+  // This test sink owns any reply messages passed into this method.
+  void SetSyncReplyMessage(IPC::Message* reply_msg);
+
   // Searches the queue for the first resource call message with a nested
   // message matching the given ID. On success, returns true and populates the
   // givem params and nested message.
   bool GetFirstResourceCallMatching(
       uint32 id,
       ResourceMessageCallParams* params,
       IPC::Message* nested_msg) const;
 
   // Like GetFirstResourceCallMatching except for replies.
   bool GetFirstResourceReplyMatching(
       uint32 id,
       ResourceMessageReplyParams* params,
       IPC::Message* nested_msg);
+
+ private:
+  scoped_ptr<IPC::Message> sync_reply_msg_;
+};
+
+// This is a message handler which generates reply messages for synchronous
+// resource calls. This allows unit testing of the plugin side of resources
+// which send sync messages. If you want to reply to a sync message type named
+// |PpapiHostMsg_X_Y| with |PpapiPluginMsg_X_YReply| then usage would be as
+// follows (from within |PluginProxyTest|s):
+//
+// PpapiHostMsg_X_YReply my_reply;
+// ResourceSyncCallHandler handler(&sink(),
+//                                 PpapiHostMsg_X_Y::ID,
+//                                 PP_OK,
+//                                 my_reply);
+// sink().AddFilter(&handler);
+// // Do stuff to send a sync message ...
+// // You can check handler.last_handled_msg() to ensure the correct message was
+// // handled.
+// sink().RemoveFilter(&handler);
+class ResourceSyncCallHandler : public IPC::Listener {
+ public:
+  ResourceSyncCallHandler(ResourceMessageTestSink* test_sink,
+                          uint32 incoming_type,
+                          int32_t result,
+                          const IPC::Message& reply_msg);
+  virtual ~ResourceSyncCallHandler();
+
+  // IPC::Listener.
+  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
+
+  IPC::Message last_handled_msg() { return last_handled_msg_; }
+
+ private:
+  ResourceMessageTestSink* test_sink_;
+  uint32 incoming_type_;
+  int32_t result_;
+  IPC::Message reply_msg_;
+  IPC::Message last_handled_msg_;
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_RESOURCE_MESSAGE_TEST_SINK_H_