Implements RTP header dumping.

chrome/browser/media/webrtc_rtp_dump_writer_unittest.cc

+// Copyright 2014 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 "base/big_endian.h"
+#include "base/bind.h"
+#include "base/file_util.h"
+#include "base/files/scoped_temp_dir.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/run_loop.h"
+#include "chrome/browser/media/webrtc_rtp_dump_writer.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/test/test_browser_thread_bundle.h"
+#include "content/public/test/test_utils.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/zlib/zlib.h"
+
+static const size_t kMinimumRtpHeaderLength = 12;
+
+static void CreateFakeRtpPacketHeader(size_t csrc_count,
+                                      size_t extension_header_count,
+                                      std::vector<uint8>* packet_header) {
+  packet_header->resize(kMinimumRtpHeaderLength + csrc_count * sizeof(uint32) +
+                        (extension_header_count + 1 * sizeof(uint32)));
+
+  // First byte format: vvpxcccc, where 'vv' is the version, 'p' is padding, 'x'
+  // is the extension bit, 'cccc' is the CSRC count.
+  (*packet_header)[0] = 0;
+  (*packet_header)[0] |= (0x2 << 6);  // version.
+  // The extension bit.
+  (*packet_header)[0] |= (extension_header_count > 0 ? (0x1 << 4) : 0);
+  (*packet_header)[0] |= (csrc_count & 0xf);
+
+  // Set extension length.
+  size_t offset =
+      kMinimumRtpHeaderLength + (csrc_count & 0xf) * sizeof(uint32) + 2;
+  base::WriteBigEndian(reinterpret_cast<char*>(packet_header + offset),
+                       static_cast<uint16>(extension_header_count));
+}
+
+class WebRtcRtpDumpWriterTest : public testing::Test {
+ public:
+  WebRtcRtpDumpWriterTest()
+      : thread_bundle_(content::TestBrowserThreadBundle::IO_MAINLOOP |
+                       content::TestBrowserThreadBundle::REAL_FILE_THREAD),
+        temp_dir_(new base::ScopedTempDir()) {}
+
+  virtual void SetUp() {
+    ASSERT_TRUE(temp_dir_->CreateUniqueTempDir());
+
+    incoming_dump_path_ = temp_dir_->path().AppendASCII("rtpdump_recv");
+    outgoing_dump_path_ = temp_dir_->path().AppendASCII("rtpdump_send");
+    writer_.reset(new WebRtcRtpDumpWriter(
+        incoming_dump_path_,
+        outgoing_dump_path_,
+        4 * 1024 * 1024,
+        base::Bind(&WebRtcRtpDumpWriterTest::OnMaxSizeReached,
+                   base::Unretained(this))));
+  }
+
+  // Verifies that the dump contains records of |rtp_packet| repeated
+  // |packet_count| times.
+  bool VerifyDumps(size_t incoming_packet_count, size_t outgoing_packet_count) {
+    std::string incoming_dump;
+    std::string outgoing_dump;
+
+    if (incoming_packet_count) {
+      EXPECT_TRUE(base::ReadFileToString(incoming_dump_path_, &incoming_dump));
+      EXPECT_TRUE(VerifyCompressedDump(&incoming_dump, incoming_packet_count));
+    } else {
+      EXPECT_FALSE(base::PathExists(incoming_dump_path_));
+    }
+
+    if (outgoing_packet_count) {
+      EXPECT_TRUE(base::ReadFileToString(outgoing_dump_path_, &outgoing_dump));
+      EXPECT_TRUE(VerifyCompressedDump(&outgoing_dump, outgoing_packet_count));
+    } else {
+      EXPECT_FALSE(base::PathExists(outgoing_dump_path_));
+    }
+
+    return true;

[tommi (sloooow) - chröme, 2014/05/17 10:18:37]

nit: this always returns true... just make it return void since it encapsulates
all the expectations?

[jiayl, 2014/05/19 17:32:59]

Done.

+  }
+
+  MOCK_METHOD2(OnEndDumpDone, void(bool, bool));
+  MOCK_METHOD0(OnMaxSizeReached, void(void));
+
+ protected:
+  // Verifies the compressed dump file contains the expected number of packets.
+  bool VerifyCompressedDump(std::string* dump, size_t expected_packet_count) {
+    EXPECT_GT(dump->size(), 0U);
+
+    std::vector<uint8> decompressed_dump;
+    EXPECT_TRUE(Decompress(dump, &decompressed_dump));
+
+    size_t actual_packet_count = 0;
+    EXPECT_TRUE(ReadDecompressedDump(decompressed_dump, &actual_packet_count));
+    EXPECT_EQ(expected_packet_count, actual_packet_count);
+
+    return true;
+  }
+
+  // Decompresses the |input| into |output|.
+  bool Decompress(std::string* input, std::vector<uint8>* output) {
+    z_stream stream = {0};
+
+    int result = inflateInit2(&stream, 15 + 16);
+    EXPECT_EQ(Z_OK, result);
+
+    output->resize(input->size() * 100);
+
+    stream.next_in =
+        reinterpret_cast<unsigned char*>(const_cast<char*>(input->data()));
+    stream.avail_in = input->size();
+    stream.next_out = output->data();
+    stream.avail_out = output->size();
+
+    result = inflate(&stream, Z_FINISH);
+    DCHECK_EQ(Z_STREAM_END, result);
+    result = inflateEnd(&stream);
+    DCHECK_EQ(Z_OK, result);
+
+    output->resize(output->size() - stream.avail_out);
+    return true;
+  }
+
+  // Tries to read |dump| as a rtpplay dump file and returns the number of
+  // packets found in the dump.
+  bool ReadDecompressedDump(const std::vector<uint8>& dump,
+                            size_t* packet_count) {
+    static const char kFirstLine[] = "#!rtpplay1.0 0.0.0.0/0\n";
+    static const size_t kDumpFileHeaderSize = 4 * sizeof(uint32);
+
+    *packet_count = 0;
+    size_t dump_pos = 0;
+
+    // Verifies the first line.
+    EXPECT_EQ(memcmp(dump.data(), kFirstLine, arraysize(kFirstLine) - 1), 0);
+
+    dump_pos += arraysize(kFirstLine) - 1;
+    EXPECT_GT(dump.size(), dump_pos);
+
+    // Skips the file header.
+    dump_pos += kDumpFileHeaderSize;
+    EXPECT_GT(dump.size(), dump_pos);
+
+    // Reads each packet dump.
+    while (dump_pos < dump.size()) {
+      size_t packet_dump_length = 0;
+      if (!VerifyPacketDump(dump.data() + dump_pos,
+                            dump.size() - dump_pos,
+                            &packet_dump_length)) {
+        DVLOG(0) << "Failed to read the packet dump for packet "
+                 << *packet_count << ", dump_pos = " << dump_pos
+                 << ", dump_length = " << dump.size();
+        return false;
+      }
+
+      EXPECT_GE(dump.size(), dump_pos + packet_dump_length);
+      dump_pos += packet_dump_length;
+
+      (*packet_count)++;
+    }
+    return true;
+  }
+
+  // Tries to read one packet dump starting at |dump| and returns the size of
+  // the packet dump.
+  bool VerifyPacketDump(const uint8* dump,
+                        size_t dump_length,
+                        size_t* packet_dump_length) {
+    static const size_t kDumpHeaderLength = 8;
+
+    size_t dump_pos = 0;
+    base::ReadBigEndian(reinterpret_cast<const char*>(dump + dump_pos),
+                        reinterpret_cast<uint16*>(packet_dump_length));
+    if (*packet_dump_length < kDumpHeaderLength + kMinimumRtpHeaderLength)
+      return false;
+
+    EXPECT_GE(dump_length, *packet_dump_length);
+    dump_pos += 2;

[tommi (sloooow) - chröme, 2014/05/17 10:18:37]

+= sizeof(uint16); ?

[jiayl, 2014/05/19 17:32:59]

Done.

+
+    uint16 rtp_packet_length = 0;
+    base::ReadBigEndian(reinterpret_cast<const char*>(dump + dump_pos),
+                        &rtp_packet_length);
+    if (rtp_packet_length < kMinimumRtpHeaderLength)
+      return false;
+
+    dump_pos += 2;

[tommi (sloooow) - chröme, 2014/05/17 10:18:37]

same here

[jiayl, 2014/05/19 17:32:59]

Done.

+
+    // Skips the elapsed time field.
+    dump_pos += 4;

[tommi (sloooow) - chröme, 2014/05/17 10:18:37]

size of the time field?

[jiayl, 2014/05/19 17:32:59]

Done.

+
+    return IsValidRtpHeader(dump + dump_pos,
+                            *packet_dump_length - kDumpHeaderLength);
+  }
+
+  // Returns true if |header| is a valid RTP header.
+  bool IsValidRtpHeader(const uint8* header, size_t length) {
+    if ((header[0] & 0xC0) != 0x80)
+      return false;
+
+    size_t cc_count = header[0] & 0x0F;
+    size_t header_length_without_extn = kMinimumRtpHeaderLength + 4 * cc_count;
+
+    if (length < header_length_without_extn)
+      return false;
+
+    uint16 extension_count = 0;
+    base::ReadBigEndian(
+        reinterpret_cast<const char*>(header + header_length_without_extn + 2),
+        &extension_count);
+
+    if (length < (extension_count + 1) * 4 + header_length_without_extn)
+      return false;
+
+    return true;
+  }
+
+  content::TestBrowserThreadBundle thread_bundle_;
+  scoped_ptr<base::ScopedTempDir> temp_dir_;
+  base::FilePath incoming_dump_path_;
+  base::FilePath outgoing_dump_path_;
+  scoped_ptr<WebRtcRtpDumpWriter> writer_;
+};
+
+TEST_F(WebRtcRtpDumpWriterTest, NoDumpFileIfNoPacketDumped) {
+  {

[tommi (sloooow) - chröme, 2014/05/17 10:18:37]

what is the scope for?

[jiayl, 2014/05/19 17:32:59]

Added comments.

+    EXPECT_CALL(*this, OnEndDumpDone(false, false));
+
+    writer_->EndDump(RTP_DUMP_BOTH,
+                     base::Bind(&WebRtcRtpDumpWriterTest::OnEndDumpDone,
+                                base::Unretained(this)));
+
+    content::RunAllPendingInMessageLoop(content::BrowserThread::FILE);
+    base::RunLoop().RunUntilIdle();
+    content::RunAllPendingInMessageLoop(content::BrowserThread::FILE);
+    base::RunLoop().RunUntilIdle();
+  }
+  EXPECT_FALSE(base::PathExists(incoming_dump_path_));
+  EXPECT_FALSE(base::PathExists(outgoing_dump_path_));
+}
+
+TEST_F(WebRtcRtpDumpWriterTest, WriteAndFlushSmallSizeDump) {
+  std::vector<uint8> packet_header;
+  CreateFakeRtpPacketHeader(1, 2, &packet_header);
+
+  writer_->WriteRtpPacket(
+      packet_header.data(), packet_header.size(), 100, true);
+
+  writer_->WriteRtpPacket(
+      packet_header.data(), packet_header.size(), 100, false);
+  {

[tommi (sloooow) - chröme, 2014/05/17 10:18:37]

same here and throughout (I'm sure I'm missing something, but if I'm not seeing
it, it might be worth documenting)

[jiayl, 2014/05/19 17:32:59]

added comments.

+    EXPECT_CALL(*this, OnEndDumpDone(true, true));
+
+    writer_->EndDump(RTP_DUMP_BOTH,
+                     base::Bind(&WebRtcRtpDumpWriterTest::OnEndDumpDone,
+                                base::Unretained(this)));
+
+    content::RunAllPendingInMessageLoop(content::BrowserThread::FILE);
+    base::RunLoop().RunUntilIdle();
+    content::RunAllPendingInMessageLoop(content::BrowserThread::FILE);
+    base::RunLoop().RunUntilIdle();
+  }
+
+  EXPECT_TRUE(VerifyDumps(1, 1));
+}
+
+TEST_F(WebRtcRtpDumpWriterTest, WriteOverMaxLimit) {
+  // Reset the writer with a small max size limit.
+  writer_.reset(new WebRtcRtpDumpWriter(
+      incoming_dump_path_,
+      outgoing_dump_path_,
+      100,
+      base::Bind(&WebRtcRtpDumpWriterTest::OnMaxSizeReached,
+                 base::Unretained(this))));
+
+  std::vector<uint8> packet_header;
+  CreateFakeRtpPacketHeader(3, 4, &packet_header);
+
+  const size_t kPacketCount = 200;
+  {
+    EXPECT_CALL(*this, OnMaxSizeReached()).Times(testing::AtLeast(1));
+
+    // Write enough packets to overflow the in-memory buffer and max limit.
+    for (size_t i = 0; i < kPacketCount; ++i) {
+      writer_->WriteRtpPacket(
+          packet_header.data(), packet_header.size(), 100, true);
+
+      writer_->WriteRtpPacket(
+          packet_header.data(), packet_header.size(), 100, false);
+    }
+
+    EXPECT_CALL(*this, OnEndDumpDone(true, true));
+
+    writer_->EndDump(RTP_DUMP_BOTH,
+                     base::Bind(&WebRtcRtpDumpWriterTest::OnEndDumpDone,
+                                base::Unretained(this)));
+
+    content::RunAllPendingInMessageLoop(content::BrowserThread::FILE);
+    base::RunLoop().RunUntilIdle();
+    content::RunAllPendingInMessageLoop(content::BrowserThread::FILE);
+    base::RunLoop().RunUntilIdle();
+  }
+  EXPECT_TRUE(VerifyDumps(kPacketCount, kPacketCount));
+}
+
+TEST_F(WebRtcRtpDumpWriterTest, DestroyWriterBeforeEndDumpCallback) {
+  EXPECT_CALL(*this, OnEndDumpDone(testing::_, testing::_)).Times(0);
+
+  writer_->EndDump(RTP_DUMP_BOTH,
+                   base::Bind(&WebRtcRtpDumpWriterTest::OnEndDumpDone,
+                              base::Unretained(this)));
+
+  writer_.reset();
+
+  content::RunAllPendingInMessageLoop(content::BrowserThread::FILE);
+  base::RunLoop().RunUntilIdle();
+  content::RunAllPendingInMessageLoop(content::BrowserThread::FILE);
+  base::RunLoop().RunUntilIdle();
+}
+
+TEST_F(WebRtcRtpDumpWriterTest, EndDumpsSeparately) {
+  std::vector<uint8> packet_header;
+  CreateFakeRtpPacketHeader(1, 2, &packet_header);
+
+  writer_->WriteRtpPacket(
+      packet_header.data(), packet_header.size(), 100, true);
+  writer_->WriteRtpPacket(
+      packet_header.data(), packet_header.size(), 100, true);
+
+  writer_->WriteRtpPacket(
+      packet_header.data(), packet_header.size(), 100, false);
+
+  {
+    EXPECT_CALL(*this, OnEndDumpDone(true, false));
+    EXPECT_CALL(*this, OnEndDumpDone(false, true));
+
+    writer_->EndDump(RTP_DUMP_INCOMING,
+                     base::Bind(&WebRtcRtpDumpWriterTest::OnEndDumpDone,
+                                base::Unretained(this)));
+
+    writer_->EndDump(RTP_DUMP_OUTGOING,
+                     base::Bind(&WebRtcRtpDumpWriterTest::OnEndDumpDone,
+                                base::Unretained(this)));
+
+    content::RunAllPendingInMessageLoop(content::BrowserThread::FILE);
+    base::RunLoop().RunUntilIdle();
+    content::RunAllPendingInMessageLoop(content::BrowserThread::FILE);
+    base::RunLoop().RunUntilIdle();
+  }
+
+  EXPECT_TRUE(VerifyDumps(2, 1));
+}