[rtp_rtcp] rtcp::Rpsi cleaned and got Parse function

webrtc/modules/rtp_rtcp/source/rtcp_packet/rpsi_unittest.cc

 /*
  *  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.
  */
 
 #include "webrtc/modules/rtp_rtcp/source/rtcp_packet/rpsi.h"
 
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
+#include "webrtc/base/checks.h"
 
-#include "webrtc/test/rtcp_packet_parser.h"
-
+using testing::ElementsAreArray;
+using testing::make_tuple;
 using webrtc::rtcp::RawPacket;
 using webrtc::rtcp::Rpsi;
-using webrtc::test::RtcpPacketParser;
+using webrtc::RTCPUtility::RtcpCommonHeader;
+using webrtc::RTCPUtility::RtcpParseCommonHeader;
 
 namespace webrtc {
+namespace {
+const uint32_t kSenderSsrc = 0x12345678;
+const uint32_t kRemoteSsrc = 0x23456789;
+// 10000|01 100001|0 1000011 (7 bits = 1 byte in native string).
+const uint64_t kPictureId = 0x106143;
+const uint8_t kPayloadType = 100;
+// Manually created Rpsi packet matching constants above.
+const uint8_t kPacket[] = {0x83, 206,  0x00, 0x04,
+                           0x12, 0x34, 0x56, 0x78,
+                           0x23, 0x45, 0x67, 0x89,
+                             24,  100, 0xc1, 0xc2,
+                           0x43,    0,    0,    0};
+
+bool ParseRpsi(const uint8_t* buffer, size_t length, Rpsi* rpsi) {
+  RtcpCommonHeader header;
+  EXPECT_TRUE(RtcpParseCommonHeader(buffer, length, &header));
+  EXPECT_EQ(length, header.BlockSize());
+  return rpsi->Parse(header, buffer + RtcpCommonHeader::kHeaderSizeBytes);
+}
+// Testing function when test only interested if parse is successful.
+bool ParseRpsi(const uint8_t* buffer, size_t length) {
+  Rpsi rpsi;
+  return ParseRpsi(buffer, length, &rpsi);
+}
+}  // namespace
+
+TEST(RtcpPacketRpsiTest, Parse) {
+  Rpsi mutable_parsed;
+  EXPECT_TRUE(ParseRpsi(kPacket, sizeof(kPacket), &mutable_parsed));
+  const Rpsi& parsed = mutable_parsed;  // Read values from constant object.
+
+  EXPECT_EQ(kSenderSsrc, parsed.sender_ssrc());
+  EXPECT_EQ(kRemoteSsrc, parsed.media_ssrc());
+  EXPECT_EQ(kPayloadType, parsed.payload_type());
+  EXPECT_EQ(kPictureId, parsed.picture_id());
+}
+
+TEST(RtcpPacketRpsiTest, Create) {
+  Rpsi rpsi;
+  rpsi.From(kSenderSsrc);
+  rpsi.To(kRemoteSsrc);
+  rpsi.WithPayloadType(kPayloadType);
+  rpsi.WithPictureId(kPictureId);
+
+  rtc::scoped_ptr<RawPacket> packet = rpsi.Build();
+
+  EXPECT_THAT(make_tuple(packet->Buffer(), packet->Length()),
+              ElementsAreArray(kPacket));
+}
+
+TEST(RtcpPacketRpsiTest, ParseFailsOnTooSmallPacket) {
+  Rpsi rpsi;
+  rpsi.From(kSenderSsrc);
+  rpsi.To(kRemoteSsrc);
+
+  rtc::scoped_ptr<RawPacket> packet = rpsi.Build();
+  packet->MutableBuffer()[3]--;  // Reduce size field by one word (4 bytes).
+
+  EXPECT_FALSE(ParseRpsi(packet->Buffer(), packet->Length() - 4));
+}
+
+TEST(RtcpPacketRpsiTest, ParseFailsOnFractionalPaddingBytes) {
+  Rpsi rpsi;
+  rpsi.From(kSenderSsrc);
+  rpsi.To(kRemoteSsrc);
+  rpsi.WithPictureId(kPictureId);
+  rtc::scoped_ptr<RawPacket> packet = rpsi.Build();
+  uint8_t* padding_bits = packet->MutableBuffer() + 12;
+  uint8_t saved_padding_bits = *padding_bits;
+  ASSERT_TRUE(ParseRpsi(packet->Buffer(), packet->Length()));
+
+  for (uint8_t i = 1; i < 8; ++i) {
+    *padding_bits = saved_padding_bits + i;
+    EXPECT_FALSE(ParseRpsi(packet->Buffer(), packet->Length()));
+  }
+}
+
+TEST(RtcpPacketRpsiTest, ParseFailsOnTooBigPadding) {
+  Rpsi rpsi;
+  rpsi.From(kSenderSsrc);
+  rpsi.To(kRemoteSsrc);
+  rpsi.WithPictureId(1);  // Small picture id that occupy just 1 byte.
+  rtc::scoped_ptr<RawPacket> packet = rpsi.Build();
+  uint8_t* padding_bits = packet->MutableBuffer() + 12;
+  ASSERT_TRUE(ParseRpsi(packet->Buffer(), packet->Length()));
+
+  *padding_bits += 8;
+  EXPECT_FALSE(ParseRpsi(packet->Buffer(), packet->Length()));
+}
+
+// For raw rpsi packet extract how many bytes are used to store picture_id.
+size_t UsedBytes(const RawPacket& packet) {  // Works for small packets only.
+  RTC_CHECK_EQ(packet.Buffer()[2], 0);       // Assume packet is small.
+  size_t total_rpsi_payload_bytes = 4 * (packet.Buffer()[3] - 2) - 2;
+  uint8_t padding_bits = packet.Buffer()[12];
+  RTC_CHECK_EQ(padding_bits % 8, 0);
+  return total_rpsi_payload_bytes - (padding_bits / 8);
+}
 
 TEST(RtcpPacketRpsiTest, WithOneByteNativeString) {
   Rpsi rpsi;
   // 1000001 (7 bits = 1 byte in native string).
   const uint64_t kPictureId = 0x41;
   const uint16_t kNumberOfValidBytes = 1;
-  rpsi.WithPayloadType(100);
   rpsi.WithPictureId(kPictureId);
 
-  rtc::scoped_ptr<RawPacket> packet(rpsi.Build());
-  RtcpPacketParser parser;
-  parser.Parse(packet->Buffer(), packet->Length());
-  EXPECT_EQ(100, parser.rpsi()->PayloadType());
-  EXPECT_EQ(kNumberOfValidBytes * 8, parser.rpsi()->NumberOfValidBits());
-  EXPECT_EQ(kPictureId, parser.rpsi()->PictureId());
+  rtc::scoped_ptr<RawPacket> packet = rpsi.Build();
+  EXPECT_EQ(kNumberOfValidBytes, UsedBytes(*packet));
+
+  Rpsi parsed;
+  EXPECT_TRUE(ParseRpsi(packet->Buffer(), packet->Length(), &parsed));
+  EXPECT_EQ(kPictureId, parsed.picture_id());
 }
 
 TEST(RtcpPacketRpsiTest, WithTwoByteNativeString) {
   Rpsi rpsi;
   // |1 0000001 (7 bits = 1 byte in native string).
   const uint64_t kPictureId = 0x81;
   const uint16_t kNumberOfValidBytes = 2;
   rpsi.WithPictureId(kPictureId);
 
-  rtc::scoped_ptr<RawPacket> packet(rpsi.Build());
-  RtcpPacketParser parser;
-  parser.Parse(packet->Buffer(), packet->Length());
-  EXPECT_EQ(kNumberOfValidBytes * 8, parser.rpsi()->NumberOfValidBits());
-  EXPECT_EQ(kPictureId, parser.rpsi()->PictureId());
+  rtc::scoped_ptr<RawPacket> packet = rpsi.Build();
+  EXPECT_EQ(kNumberOfValidBytes, UsedBytes(*packet));
+
+  Rpsi parsed;
+  EXPECT_TRUE(ParseRpsi(packet->Buffer(), packet->Length(), &parsed));
+  EXPECT_EQ(kPictureId, parsed.picture_id());
 }
 
 TEST(RtcpPacketRpsiTest, WithThreeByteNativeString) {
   Rpsi rpsi;
   // 10000|00 100000|0 1000000 (7 bits = 1 byte in native string).
   const uint64_t kPictureId = 0x102040;
   const uint16_t kNumberOfValidBytes = 3;
   rpsi.WithPictureId(kPictureId);
 
-  rtc::scoped_ptr<RawPacket> packet(rpsi.Build());
-  RtcpPacketParser parser;
-  parser.Parse(packet->Buffer(), packet->Length());
-  EXPECT_EQ(kNumberOfValidBytes * 8, parser.rpsi()->NumberOfValidBits());
-  EXPECT_EQ(kPictureId, parser.rpsi()->PictureId());
+  rtc::scoped_ptr<RawPacket> packet = rpsi.Build();
+  EXPECT_EQ(kNumberOfValidBytes, UsedBytes(*packet));
+
+  Rpsi parsed;
+  EXPECT_TRUE(ParseRpsi(packet->Buffer(), packet->Length(), &parsed));
+  EXPECT_EQ(kPictureId, parsed.picture_id());
 }
 
 TEST(RtcpPacketRpsiTest, WithFourByteNativeString) {
   Rpsi rpsi;
   // 1000|001 00001|01 100001|1 1000010 (7 bits = 1 byte in native string).
   const uint64_t kPictureId = 0x84161C2;
   const uint16_t kNumberOfValidBytes = 4;
   rpsi.WithPictureId(kPictureId);
 
-  rtc::scoped_ptr<RawPacket> packet(rpsi.Build());
-  RtcpPacketParser parser;
-  parser.Parse(packet->Buffer(), packet->Length());
-  EXPECT_EQ(kNumberOfValidBytes * 8, parser.rpsi()->NumberOfValidBits());
-  EXPECT_EQ(kPictureId, parser.rpsi()->PictureId());
+  rtc::scoped_ptr<RawPacket> packet = rpsi.Build();
+  EXPECT_EQ(kNumberOfValidBytes, UsedBytes(*packet));
+
+  Rpsi parsed;
+  EXPECT_TRUE(ParseRpsi(packet->Buffer(), packet->Length(), &parsed));
+  EXPECT_EQ(kPictureId, parsed.picture_id());
 }
 
 TEST(RtcpPacketRpsiTest, WithMaxPictureId) {
   Rpsi rpsi;
   // 1 1111111| 1111111 1|111111 11|11111 111|1111 1111|111 11111|
   // 11 111111|1 1111111 (7 bits = 1 byte in native string).
   const uint64_t kPictureId = 0xffffffffffffffff;
   const uint16_t kNumberOfValidBytes = 10;
   rpsi.WithPictureId(kPictureId);
 
-  rtc::scoped_ptr<RawPacket> packet(rpsi.Build());
-  RtcpPacketParser parser;
-  parser.Parse(packet->Buffer(), packet->Length());
-  EXPECT_EQ(kNumberOfValidBytes * 8, parser.rpsi()->NumberOfValidBits());
-  EXPECT_EQ(kPictureId, parser.rpsi()->PictureId());
+  rtc::scoped_ptr<RawPacket> packet = rpsi.Build();
+  EXPECT_EQ(kNumberOfValidBytes, UsedBytes(*packet));
+
+  Rpsi parsed;
+  EXPECT_TRUE(ParseRpsi(packet->Buffer(), packet->Length(), &parsed));
+  EXPECT_EQ(kPictureId, parsed.picture_id());
 }
-
 }  // namespace webrtc