[Draft] RTCP Parser sketched.

webrtc/modules/rtp_rtcp/source/sample_rtcp_parser2.h

+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ *
+ */
+
+#ifndef WEBRTC_MODULES_RTP_RTCP_SOURCE_SAMPLE_RTCP_PARSER2_H_
+#define WEBRTC_MODULES_RTP_RTCP_SOURCE_SAMPLE_RTCP_PARSER2_H_
+
+#include "webrtc/modules/rtp_rtcp/source/rtcp_packet/app.h"
+#include "webrtc/modules/rtp_rtcp/source/rtcp_packet/bye.h"
+#include "webrtc/modules/rtp_rtcp/source/rtcp_packet/parsing_container.h"
+#include "webrtc/modules/rtp_rtcp/source/rtcp_packet/pli.h"
+
+namespace webrtc {
+namespace rtcp {
+/* Parser that rely on ParsingContainer that wraps CommonHeader in it. */
+
+class Parser2 {
+ public:
+  void Parse(const uint8_t* buffer, size_t length) {
+    for (const auto& header : ParsingContainer(buffer, length)) {
+      ParseIndividual(header);
+    }
+  }
+
+ protected:
+  virtual ~Parser2() {}
+  virtual void HandleApp(const App&) {}
+  virtual void HandleBye(const Bye&) {}
+  virtual void HandlePli(const Pli&) {}
+  virtual void HandleUnknown(const CommonHeader&) {}
+  virtual void HandleInvalid() {}
+
+ private:
+  inline void HandleParsed(const App& app) { HandleApp(app); }
+  inline void HandleParsed(const Bye& bye) { HandleBye(bye); }
+  inline void HandleParsed(const Pli& pli) { HandlePli(pli); }
+
+  template <typename TypedPacket>
+  void HandleUnparsed(const CommonHeader& packet) {
+    TypedPacket parsed;
+    if (!parsed.Parse(packet))
+      HandleInvalid();
+    else
+      HandleParsed(parsed);
+  }
+
+  void ParseIndividual(const CommonHeader& header) {
+    switch (header.type()) {
+      case App::kPacketType:
+        HandleUnparsed<App>(header);
+        break;
+      case Bye::kPacketType:
+        HandleUnparsed<Bye>(header);
+        break;
+      case Psfb::kPacketType:
+        switch (header.fmt()) {
+          case Pli::kFeedbackMessageType:
+            HandleUnparsed<Pli>(header);
+            break;
+          default:
+            HandleUnknown(header);
+            break;
+        }
+        break;
+      default:
+        HandleUnknown(header);
+        break;
+    }
+  }
+};
+}  // namespace rtcp
+}  // namespace webrtc
+#endif  // WEBRTC_MODULES_RTP_RTCP_SOURCE_SAMPLE_RTCP_PARSER2_H_