Refactored CL for moving the output to a separate thread.

webrtc/call/ringbuffer_unittest.cc

+/*
+ *  Copyright (c) 2015 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 <list>
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "webrtc/base/random.h"
+#include "webrtc/call/ringbuffer.h"
+
+namespace webrtc {
+
+// Verify that the ring buffer works as a simple queue.
+TEST(RingBufferTest, SimpleQueue) {
+  size_t capacity = 100;
+  RingBuffer<int> q(capacity);
+  EXPECT_TRUE(q.empty());
+  for (size_t i = 0; i < capacity; i++) {
+    q.push_back(static_cast<int>(i));
+    EXPECT_FALSE(q.empty());
+  }
+
+  for (size_t i = 0; i < capacity; i++) {
+    EXPECT_FALSE(q.empty());
+    EXPECT_EQ(static_cast<int>(i), q.front());
+    q.pop_front();
+  }
+  EXPECT_TRUE(q.empty());
+}
+
+// Do a "random" sequence of queue operations and verify that the
+// result is consistent with the same operation performed on a std::list.
+TEST(RingBufferTest, ConsistentWithStdList) {
+  Random prng(987654321ull);
+  size_t capacity = 10;
+  RingBuffer<int> q(capacity);
+  std::list<int> l;
+  EXPECT_TRUE(q.empty());
+  for (size_t i = 0; i < 100 * capacity; i++) {
+    bool insert = prng.Rand<bool>();
+    if ((insert && l.size() < capacity) || l.size() == 0) {
+      int x = prng.Rand<int>();
+      l.push_back(x);
+      q.push_back(x);
+      EXPECT_FALSE(q.empty());
+    } else {
+      EXPECT_FALSE(q.empty());
+      EXPECT_EQ(l.front(), q.front());
+      l.pop_front();
+      q.pop_front();
+    }
+  }
+  while (!l.empty()) {
+    EXPECT_FALSE(q.empty());
+    EXPECT_EQ(l.front(), q.front());
+    l.pop_front();
+    q.pop_front();
+  }
+  EXPECT_TRUE(q.empty());
+}
+
+// Test that the ringbuffer starts reusing elements from the front
+// when the queue becomes full.
+TEST(RingBufferTest, OverwriteOldElements) {
+  size_t capacity = 100;
+  int insertions = 3 * capacity + 25;
+  RingBuffer<int> q(capacity);
+  EXPECT_TRUE(q.empty());
+  for (int i = 0; i < insertions; i++) {
+    q.push_back(i);
+    EXPECT_FALSE(q.empty());
+  }
+
+  for (int i = insertions - capacity; i < insertions; i++) {
+    EXPECT_FALSE(q.empty());
+    EXPECT_EQ(i, q.front());
+    q.pop_front();
+  }
+  EXPECT_TRUE(q.empty());
+}
+
+TEST(RingBufferTest, SmallCapacity) {
+  size_t capacity = 1;
+  RingBuffer<int> q(capacity);
+  EXPECT_TRUE(q.empty());
+  q.push_back(4711);
+  EXPECT_FALSE(q.empty());
+  EXPECT_EQ(4711, q.front());
+  q.push_back(1024);
+  EXPECT_FALSE(q.empty());
+  EXPECT_EQ(1024, q.front());
+  q.pop_front();
+  EXPECT_TRUE(q.empty());
+}
+
+}  // namespace webrtc