[rtp_rtcp] rtcp::Sli packet moved into own file and got Parse function

webrtc/modules/rtp_rtcp/source/rtcp_packet/sli.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_RTCP_PACKET_SLI_H_
+#define WEBRTC_MODULES_RTP_RTCP_SOURCE_RTCP_PACKET_SLI_H_
+
+#include <vector>
+
+#include "webrtc/base/basictypes.h"
+#include "webrtc/modules/rtp_rtcp/source/rtcp_packet/psfb.h"
+#include "webrtc/modules/rtp_rtcp/source/rtcp_utility.h"
+
+namespace webrtc {
+namespace rtcp {
+
+// Slice loss indication (SLI) (RFC 4585).
+class Sli : public Psfb {
+ public:
+  static const uint8_t kFeedbackMessageType = 2;
+  class Macroblocks {
+   public:
+    static const size_t kLength = 4;
+    Macroblocks() : item_(0) {}
+    Macroblocks(uint8_t picture_id, uint16_t first, uint16_t number);
+    ~Macroblocks() {}
+
+    void Parse(const uint8_t* buffer);
+    void Create(uint8_t* buffer) const;
+
+    uint16_t first() const { return item_ >> 19; }
+    uint16_t number() const { return (item_ >> 6) & 0x1fff; }
+    uint8_t picture_id() const { return (item_ & 0x3f); }
+
+   private:
+    uint32_t item_;
+  };
+
+  Sli() {}
+  virtual ~Sli() {}
+
+  // Parse assumes header is already parsed and validated.
+  bool Parse(const RTCPUtility::RtcpCommonHeader& header,
+             const uint8_t* payload);  // Size of the payload is in the header.
+
+  void WithPictureId(uint8_t picture_id,
+                     uint16_t first_macroblock = 0,
+                     uint16_t number_macroblocks = 0x1fff) {
+    items_.push_back(
+        Macroblocks(picture_id, first_macroblock, number_macroblocks));
+  }
+
+  const std::vector<Macroblocks>& macroblocks() const { return items_; }
+
+ protected:
+  bool Create(uint8_t* packet,
+              size_t* index,
+              size_t max_length,
+              RtcpPacket::PacketReadyCallback* callback) const override;
+
+ private:
+  size_t BlockLength() const override {
+    return RtcpPacket::kHeaderLength + Psfb::kCommonFeedbackLength +
+           items_.size() * Macroblocks::kLength;
+  }
+
+  std::vector<Macroblocks> items_;
+
+  RTC_DISALLOW_COPY_AND_ASSIGN(Sli);
+};
+
+}  // namespace rtcp
+}  // namespace webrtc
+#endif  // WEBRTC_MODULES_RTP_RTCP_SOURCE_RTCP_PACKET_SLI_H_