Introduce AudioBus to replace std::vector<float*>.

media/base/audio_bus_unittest.cc

Index: media/base/audio_bus_unittest.cc
diff --git a/media/base/audio_bus_unittest.cc b/media/base/audio_bus_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b716de8eb88e1bcba470097e375b35e86eafe9f4
--- /dev/null
+++ b/media/base/audio_bus_unittest.cc
@@ -0,0 +1,106 @@
+// 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.
+
+#include "media/base/audio_bus.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+static const int kChannels = 6;
+static const ChannelLayout kChannelLayout = CHANNEL_LAYOUT_5_1;
+// Use a buffer size which is intentionally not a multiple of 16.
+static const int kFrameCount = 1234;
+
+namespace media {
+
+class AudioBusTest : public testing::Test {
+ public:
+  AudioBusTest() {}
+  ~AudioBusTest() {
+    for (size_t i = 0; i < audio_data_.size(); ++i)
+      base::AlignedFree(audio_data_[i]);
+  }
+
+  // Validate parameters returned by AudioBus v.s. the constructed parameters.
+  void VerifyParams(AudioBus* bus) {
+    EXPECT_EQ(kChannels, bus->channels());
+    EXPECT_EQ(kFrameCount, bus->frames());
+  }
+
+  void VerifyValue(const float data[], int size, float value) {
+    for (int i = 0; i < size; ++i)
+      ASSERT_FLOAT_EQ(value, data[i]);
+  }
+
+  // Read and write to the full extent of the allocated channel data.  Also test
+  // the Zero() method and verify it does as advertised.  Also test data if data
+  // is aligned properly.
+  void VerifyChannelData(AudioBus* bus) {
+    for (int i = 0; i < bus->channels(); ++i) {
+      ASSERT_EQ(0U, reinterpret_cast<uintptr_t>(bus->channel(i)) & 0x0F);
+      std::fill(bus->channel(i), bus->channel(i) + bus->frames(), i);
+    }
+
+    for (int i = 0; i < bus->channels(); ++i)
+      VerifyValue(bus->channel(i), bus->frames(), i);
+
+    bus->Zero();
+    for (int i = 0; i < bus->channels(); ++i)
+      VerifyValue(bus->channel(i), bus->frames(), 0);
+  }
+
+
+ protected:
+  std::vector<float*> audio_data_;
+
+  DISALLOW_COPY_AND_ASSIGN(AudioBusTest);
+};
+
+TEST_F(AudioBusTest, CreateAndSetLayout) {
+  scoped_ptr<AudioBus> bus = AudioBus::Create(kChannels, kFrameCount);
+  VerifyParams(bus.get());
+  VerifyChannelData(bus.get());
+  EXPECT_EQ(CHANNEL_LAYOUT_NONE, bus->channel_layout());
+  bus->set_channel_layout(kChannelLayout);
+  EXPECT_EQ(kChannelLayout, bus->channel_layout());
+}
+
+TEST_F(AudioBusTest, CreateUsingAudioParameters) {
+  scoped_ptr<AudioBus> bus = AudioBus::Create(AudioParameters(
+      AudioParameters::AUDIO_PCM_LINEAR, kChannelLayout, 48000, 32,
+      kFrameCount));
+  VerifyParams(bus.get());
+  VerifyChannelData(bus.get());
+  EXPECT_EQ(kChannelLayout, bus->channel_layout());
+}
+
+TEST_F(AudioBusTest, Wrap) {
+  audio_data_.reserve(kChannels);
+  for (int i = 0; i < kChannels; ++i) {
+    audio_data_.push_back(static_cast<float*>(base::AlignedAlloc(
+        sizeof(*audio_data_[i]) * kFrameCount, 16)));
+  }
+
+  scoped_ptr<AudioBus> bus = AudioBus::WrapVector(kFrameCount, audio_data_);
+  VerifyParams(bus.get());
+  VerifyChannelData(bus.get());
+}
+
+// Simulate a shared memory transfer and verify results.
+TEST_F(AudioBusTest, AudioData) {
+  scoped_ptr<AudioBus> bus = AudioBus::Create(kChannels, kFrameCount);
+  scoped_ptr<AudioBus> bus2 = AudioBus::Create(kChannels, kFrameCount);
+
+  // Fill first bus with dummy data and zero out the second bus.
+  for (int i = 0; i < bus->channels(); ++i)
+    std::fill(bus->channel(i), bus->channel(i) + bus->frames(), i);
+  bus2->Zero();
+
+  // Transfer audio data from |bus| to |bus2|.
+  ASSERT_EQ(bus->audio_data_size(), bus2->audio_data_size());
+  memcpy(bus2->audio_data(), bus->audio_data(), bus->audio_data_size());
+
+  for (int i = 0; i < bus2->channels(); ++i)
+    VerifyValue(bus2->channel(i), bus2->frames(), i);
+}
+
+}  // namespace media