Introduce PushPullFIFO class and remove other FIFOs

third_party/WebKit/Source/platform/audio/PushPullFIFOTest.cpp

Index: third_party/WebKit/Source/platform/audio/PushPullFIFOTest.cpp
diff --git a/third_party/WebKit/Source/platform/audio/PushPullFIFOTest.cpp b/third_party/WebKit/Source/platform/audio/PushPullFIFOTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..c66482a6fa035d6c5dbc9b4fd11f7c6d08113f02
--- /dev/null
+++ b/third_party/WebKit/Source/platform/audio/PushPullFIFOTest.cpp
@@ -0,0 +1,135 @@
+// Copyright 2016 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 "platform/audio/PushPullFIFO.h"
+
+#include "platform/audio/AudioUtilities.h"
+#include "platform/testing/TestingPlatformSupport.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "wtf/PtrUtil.h"
+#include <memory>
+
+namespace blink {
+
+namespace {
+
+void fillBusWithValue(AudioBus* targetBus, float value) {
+  for (unsigned c = 0; c < targetBus->numberOfChannels(); ++c) {
+    float* busChannel = targetBus->channel(c)->mutableData();
+    std::fill(busChannel, busChannel + targetBus->channel(c)->length(), value);
+  }
+}
+
+// Fills up an array with a series of indexes; [0, 1, 2, 3, 4, 5, 6, ....]
+void fillBusWithIncrementalIndex(AudioBus* targetBus) {
+  for (unsigned c = 0; c < targetBus->numberOfChannels(); ++c) {
+    float* busChannel = targetBus->channel(c)->mutableData();
+    for (unsigned i = 0; i < targetBus->channel(c)->length(); ++i)
+      busChannel[i] = i;
+  }
+}
+
+bool verifyBusValueAtIndex(AudioBus* targetBus, int index, float value) {
+  for (unsigned c = 0; c < targetBus->numberOfChannels(); ++c) {
+    float* busChannel = targetBus->channel(c)->mutableData();
+    if (busChannel[index] != value) {
+      LOG(ERROR) << "[FAIL] index = " << index
+                 << " value = " << busChannel[index];
+      return false;
+    }
+  }
+  return true;
+}
+
+struct PushPullFIFOTestParam {
+  PushPullFIFOTestParam(size_t fifoSize,
+                        unsigned numberOfChannels,
+                        size_t framesAvailable,
+                        size_t framesToPush,
+                        size_t framesToPull,
+                        unsigned expectedReadIndex,
+                        float expectedValueAtReadIndex,
+                        unsigned expectedWriteIndex,
+                        float expectedValueAtWriteIndex)
+      : fifoSize(fifoSize),
+        numberOfChannels(numberOfChannels),
+        framesAvailable(framesAvailable),
+        framesToPush(framesToPush),
+        framesToPull(framesToPull),
+        expectedReadIndex(expectedReadIndex),
+        expectedValueAtReadIndex(expectedValueAtReadIndex),
+        expectedWriteIndex(expectedWriteIndex),
+        expectedValueAtWriteIndex(expectedValueAtWriteIndex) {}
+  ~PushPullFIFOTestParam() {}
+
+  const size_t fifoSize;

[o1ka, 2017/01/24 11:09:02]

Could you provide comments on what each value means?

[hongchan, 2017/01/26 22:33:18]

I have restructured the unit test. PTAL the new design.

+  const unsigned numberOfChannels;
+  const size_t framesAvailable;
+  const size_t framesToPush;
+  const size_t framesToPull;
+  const unsigned expectedReadIndex;
+  const float expectedValueAtReadIndex;
+  const unsigned expectedWriteIndex;
+  const float expectedValueAtWriteIndex;
+};
+
+std::ostream& operator<<(std::ostream& out,
+                         const PushPullFIFOTestParam& param) {
+  out << "fifoSze=" << param.fifoSize
+      << " numberOfChannels=" << param.numberOfChannels
+      << " framesAvailable=" << param.framesAvailable
+      << " framesToPush=" << param.framesToPush
+      << " framesToPull=" << param.framesToPull
+      << " expectedReadIndex=" << param.expectedReadIndex
+      << " expectedValueAtReadIndex=" << param.expectedValueAtReadIndex
+      << " expectedWriteIndex=" << param.expectedWriteIndex
+      << " expectedValueAtWriteIndex=" << param.expectedValueAtWriteIndex;
+  return out;
+}
+
+class PushPullFIFOTest
+    : public ::testing::TestWithParam<PushPullFIFOTestParam> {};
+
+TEST_P(PushPullFIFOTest, BasicOperation) {
+  std::unique_ptr<PushPullFIFO> fifo = WTF::wrapUnique(
+      new PushPullFIFO(GetParam().numberOfChannels, GetParam().fifoSize));
+
+  // Simulates existing frames in the FIFO. These frames are initialized with
+  // -1.
+  RefPtr<AudioBus> existingBus =
+      AudioBus::create(GetParam().numberOfChannels, GetParam().framesAvailable);
+  fillBusWithValue(existingBus.get(), -1);
+  fifo->push(existingBus.get());
+
+  // Then push data with given length. The content of input bus is a series of
+  // incremental index.
+  RefPtr<AudioBus> inputBus =
+      AudioBus::create(GetParam().numberOfChannels, GetParam().framesToPush);
+  fillBusWithIncrementalIndex(inputBus.get());
+  fifo->push(inputBus.get());
+
+  // Lastly, pull the data from FIFO to reach the state required by
+  // |framesToPull|.
+  RefPtr<AudioBus> outputBus =

[o1ka, 2017/01/24 11:09:02]

This looks good.
Another set of cases to test is long sequences of pulls and pushes with
different patterns (m pushes in a row, n pulls in a row), starting from an empty
fifo.

[hongchan, 2017/01/26 22:33:18]

Done.

+      AudioBus::create(GetParam().numberOfChannels, GetParam().framesToPull);
+  fifo->pull(outputBus.get(), GetParam().framesToPull);
+
+  // Verify the position of current indexes and their values.

[o1ka, 2017/01/24 11:09:02]

We also want to check the content of |outputBus|.

[hongchan, 2017/01/26 22:33:18]

Done.

+  EXPECT_EQ(true,
+            verifyBusValueAtIndex(fifo->bus(), GetParam().expectedReadIndex,
+                                  GetParam().expectedValueAtReadIndex));
+  EXPECT_EQ(true,
+            verifyBusValueAtIndex(fifo->bus(), GetParam().expectedWriteIndex,
+                                  GetParam().expectedValueAtWriteIndex));
+}
+
+INSTANTIATE_TEST_CASE_P(
+    PushPullFIFOTest,
+    PushPullFIFOTest,
+    ::testing::Values(
+        PushPullFIFOTestParam(8192, 2, 128, 256, 128, 128, 0, 384, 0)));
+
+}  // namespace
+
+}  // namespace blink