1 files changed, 105 insertions, 0 deletions
diff --git a/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/decoder/DecoderCounters.java b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/decoder/DecoderCounters.java
new file mode 100644
index 0000000000..f8bdb9b29a
--- /dev/null
+++ b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/decoder/DecoderCounters.java
@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.mozilla.thirdparty.com.google.android.exoplayer2.decoder;
+
+/**
+ * Maintains decoder event counts, for debugging purposes only.
+ * <p>
+ * Counters should be written from the playback thread only. Counters may be read from any thread.
+ * To ensure that the counter values are made visible across threads, users of this class should
+ * invoke {@link #ensureUpdated()} prior to reading and after writing.
+ */
+public final class DecoderCounters {
+
+  /**
+   * The number of times a decoder has been initialized.
+   */
+  public int decoderInitCount;
+  /**
+   * The number of times a decoder has been released.
+   */
+  public int decoderReleaseCount;
+  /**
+   * The number of queued input buffers.
+   */
+  public int inputBufferCount;
+  /**
+   * The number of skipped input buffers.
+   * <p>
+   * A skipped input buffer is an input buffer that was deliberately not sent to the decoder.
+   */
+  public int skippedInputBufferCount;
+  /**
+   * The number of rendered output buffers.
+   */
+  public int renderedOutputBufferCount;
+  /**
+   * The number of skipped output buffers.
+   * <p>
+   * A skipped output buffer is an output buffer that was deliberately not rendered.
+   */
+  public int skippedOutputBufferCount;
+  /**
+   * The number of dropped buffers.
+   * <p>
+   * A dropped buffer is an buffer that was supposed to be decoded/rendered, but was instead
+   * dropped because it could not be rendered in time.
+   */
+  public int droppedBufferCount;
+  /**
+   * The maximum number of dropped buffers without an interleaving rendered output buffer.
+   * <p>
+   * Skipped output buffers are ignored for the purposes of calculating this value.
+   */
+  public int maxConsecutiveDroppedBufferCount;
+  /**
+   * The number of times all buffers to a keyframe were dropped.
+   * <p>
+   * Each time buffers to a keyframe are dropped, this counter is increased by one, and the dropped
+   * buffer counters are increased by one (for the current output buffer) plus the number of buffers
+   * dropped from the source to advance to the keyframe.
+   */
+  public int droppedToKeyframeCount;
+
+  /**
+   * Should be called to ensure counter values are made visible across threads. The playback thread
+   * should call this method after updating the counter values. Any other thread should call this
+   * method before reading the counters.
+   */
+  public synchronized void ensureUpdated() {
+    // Do nothing. The use of synchronized ensures a memory barrier should another thread also
+    // call this method.
+  }
+
+  /**
+   * Merges the counts from {@code other} into this instance.
+   *
+   * @param other The {@link DecoderCounters} to merge into this instance.
+   */
+  public void merge(DecoderCounters other) {
+    decoderInitCount += other.decoderInitCount;
+    decoderReleaseCount += other.decoderReleaseCount;
+    inputBufferCount += other.inputBufferCount;
+    skippedInputBufferCount += other.skippedInputBufferCount;
+    renderedOutputBufferCount += other.renderedOutputBufferCount;
+    skippedOutputBufferCount += other.skippedOutputBufferCount;
+    droppedBufferCount += other.droppedBufferCount;
+    maxConsecutiveDroppedBufferCount = Math.max(maxConsecutiveDroppedBufferCount,
+        other.maxConsecutiveDroppedBufferCount);
+    droppedToKeyframeCount += other.droppedToKeyframeCount;
+  }
+
+}