1 files changed, 155 insertions, 0 deletions
diff --git a/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/extractor/ogg/OggPacket.java b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/extractor/ogg/OggPacket.java
new file mode 100644
index 0000000000..1f3bf38c73
--- /dev/null
+++ b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/extractor/ogg/OggPacket.java
@@ -0,0 +1,155 @@
+/*
+ * 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.extractor.ogg;
+
+import org.mozilla.thirdparty.com.google.android.exoplayer2.C;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.extractor.ExtractorInput;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.Assertions;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.ParsableByteArray;
+import java.io.IOException;
+import java.util.Arrays;
+
+/**
+ * OGG packet class.
+ */
+/* package */ final class OggPacket {
+
+  private final OggPageHeader pageHeader = new OggPageHeader();
+  private final ParsableByteArray packetArray = new ParsableByteArray(
+      new byte[OggPageHeader.MAX_PAGE_PAYLOAD], 0);
+
+  private int currentSegmentIndex = C.INDEX_UNSET;
+  private int segmentCount;
+  private boolean populated;
+
+  /**
+   * Resets this reader.
+   */
+  public void reset() {
+    pageHeader.reset();
+    packetArray.reset();
+    currentSegmentIndex = C.INDEX_UNSET;
+    populated = false;
+  }
+
+  /**
+   * Reads the next packet of the ogg stream. In case of an {@code IOException} the caller must make
+   * sure to pass the same instance of {@code ParsableByteArray} to this method again so this reader
+   * can resume properly from an error while reading a continued packet spanned across multiple
+   * pages.
+   *
+   * @param input The {@link ExtractorInput} to read data from.
+   * @return {@code true} if the read was successful. The read fails if the end of the input is
+   *     encountered without reading data.
+   * @throws IOException If reading from the input fails.
+   * @throws InterruptedException If the thread is interrupted.
+   */
+  public boolean populate(ExtractorInput input) throws IOException, InterruptedException {
+    Assertions.checkState(input != null);
+
+    if (populated) {
+      populated = false;
+      packetArray.reset();
+    }
+
+    while (!populated) {
+      if (currentSegmentIndex < 0) {
+        // We're at the start of a page.
+        if (!pageHeader.populate(input, true)) {
+          return false;
+        }
+        int segmentIndex = 0;
+        int bytesToSkip = pageHeader.headerSize;
+        if ((pageHeader.type & 0x01) == 0x01 && packetArray.limit() == 0) {
+          // After seeking, the first packet may be the remainder
+          // part of a continued packet which has to be discarded.
+          bytesToSkip += calculatePacketSize(segmentIndex);
+          segmentIndex += segmentCount;
+        }
+        input.skipFully(bytesToSkip);
+        currentSegmentIndex = segmentIndex;
+      }
+
+      int size = calculatePacketSize(currentSegmentIndex);
+      int segmentIndex = currentSegmentIndex + segmentCount;
+      if (size > 0) {
+        if (packetArray.capacity() < packetArray.limit() + size) {
+          packetArray.data = Arrays.copyOf(packetArray.data, packetArray.limit() + size);
+        }
+        input.readFully(packetArray.data, packetArray.limit(), size);
+        packetArray.setLimit(packetArray.limit() + size);
+        populated = pageHeader.laces[segmentIndex - 1] != 255;
+      }
+      // Advance now since we are sure reading didn't throw an exception.
+      currentSegmentIndex = segmentIndex == pageHeader.pageSegmentCount ? C.INDEX_UNSET
+          : segmentIndex;
+    }
+    return true;
+  }
+
+  /**
+   * An OGG Packet may span multiple pages. Returns the {@link OggPageHeader} of the last page read,
+   * or an empty header if the packet has yet to be populated.
+   *
+   * <p>Note that the returned {@link OggPageHeader} is mutable and may be updated during subsequent
+   * calls to {@link #populate(ExtractorInput)}.
+   *
+   * @return the {@code PageHeader} of the last page read or an empty header if the packet has yet
+   *     to be populated.
+   */
+  public OggPageHeader getPageHeader() {
+    return pageHeader;
+  }
+
+  /**
+   * Returns a {@link ParsableByteArray} containing the packet's payload.
+   */
+  public ParsableByteArray getPayload() {
+    return packetArray;
+  }
+
+  /**
+   * Trims the packet data array.
+   */
+  public void trimPayload() {
+    if (packetArray.data.length == OggPageHeader.MAX_PAGE_PAYLOAD) {
+      return;
+    }
+    packetArray.data = Arrays.copyOf(packetArray.data, Math.max(OggPageHeader.MAX_PAGE_PAYLOAD,
+        packetArray.limit()));
+  }
+
+  /**
+   * Calculates the size of the packet starting from {@code startSegmentIndex}.
+   *
+   * @param startSegmentIndex the index of the first segment of the packet.
+   * @return Size of the packet.
+   */
+  private int calculatePacketSize(int startSegmentIndex) {
+    segmentCount = 0;
+    int size = 0;
+    while (startSegmentIndex + segmentCount < pageHeader.pageSegmentCount) {
+      int segmentLength = pageHeader.laces[startSegmentIndex + segmentCount++];
+      size += segmentLength;
+      if (segmentLength != 255) {
+        // packets end at first lace < 255
+        break;
+      }
+    }
+    return size;
+  }
+
+}