1 files changed, 227 insertions, 0 deletions
diff --git a/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/extractor/flv/ScriptTagPayloadReader.java b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/extractor/flv/ScriptTagPayloadReader.java
new file mode 100644
index 0000000000..1494bf1c2e
--- /dev/null
+++ b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/extractor/flv/ScriptTagPayloadReader.java
@@ -0,0 +1,227 @@
+/*
+ * 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.flv;
+
+import androidx.annotation.Nullable;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.C;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.ParserException;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.extractor.DummyTrackOutput;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.ParsableByteArray;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Parses Script Data tags from an FLV stream and extracts metadata information.
+ */
+/* package */ final class ScriptTagPayloadReader extends TagPayloadReader {
+
+  private static final String NAME_METADATA = "onMetaData";
+  private static final String KEY_DURATION = "duration";
+
+  // AMF object types
+  private static final int AMF_TYPE_NUMBER = 0;
+  private static final int AMF_TYPE_BOOLEAN = 1;
+  private static final int AMF_TYPE_STRING = 2;
+  private static final int AMF_TYPE_OBJECT = 3;
+  private static final int AMF_TYPE_ECMA_ARRAY = 8;
+  private static final int AMF_TYPE_END_MARKER = 9;
+  private static final int AMF_TYPE_STRICT_ARRAY = 10;
+  private static final int AMF_TYPE_DATE = 11;
+
+  private long durationUs;
+
+  public ScriptTagPayloadReader() {
+    super(new DummyTrackOutput());
+    durationUs = C.TIME_UNSET;
+  }
+
+  public long getDurationUs() {
+    return durationUs;
+  }
+
+  @Override
+  public void seek() {
+    // Do nothing.
+  }
+
+  @Override
+  protected boolean parseHeader(ParsableByteArray data) {
+    return true;
+  }
+
+  @Override
+  protected boolean parsePayload(ParsableByteArray data, long timeUs) throws ParserException {
+    int nameType = readAmfType(data);
+    if (nameType != AMF_TYPE_STRING) {
+      // Should never happen.
+      throw new ParserException();
+    }
+    String name = readAmfString(data);
+    if (!NAME_METADATA.equals(name)) {
+      // We're only interested in metadata.
+      return false;
+    }
+    int type = readAmfType(data);
+    if (type != AMF_TYPE_ECMA_ARRAY) {
+      // We're not interested in this metadata.
+      return false;
+    }
+    // Set the duration to the value contained in the metadata, if present.
+    Map<String, Object> metadata = readAmfEcmaArray(data);
+    if (metadata.containsKey(KEY_DURATION)) {
+      double durationSeconds = (double) metadata.get(KEY_DURATION);
+      if (durationSeconds > 0.0) {
+        durationUs = (long) (durationSeconds * C.MICROS_PER_SECOND);
+      }
+    }
+    return false;
+  }
+
+  private static int readAmfType(ParsableByteArray data) {
+    return data.readUnsignedByte();
+  }
+
+  /**
+   * Read a boolean from an AMF encoded buffer.
+   *
+   * @param data The buffer from which to read.
+   * @return The value read from the buffer.
+   */
+  private static Boolean readAmfBoolean(ParsableByteArray data) {
+    return data.readUnsignedByte() == 1;
+  }
+
+  /**
+   * Read a double number from an AMF encoded buffer.
+   *
+   * @param data The buffer from which to read.
+   * @return The value read from the buffer.
+   */
+  private static Double readAmfDouble(ParsableByteArray data) {
+    return Double.longBitsToDouble(data.readLong());
+  }
+
+  /**
+   * Read a string from an AMF encoded buffer.
+   *
+   * @param data The buffer from which to read.
+   * @return The value read from the buffer.
+   */
+  private static String readAmfString(ParsableByteArray data) {
+    int size = data.readUnsignedShort();
+    int position = data.getPosition();
+    data.skipBytes(size);
+    return new String(data.data, position, size);
+  }
+
+  /**
+   * Read an array from an AMF encoded buffer.
+   *
+   * @param data The buffer from which to read.
+   * @return The value read from the buffer.
+   */
+  private static ArrayList<Object> readAmfStrictArray(ParsableByteArray data) {
+    int count = data.readUnsignedIntToInt();
+    ArrayList<Object> list = new ArrayList<>(count);
+    for (int i = 0; i < count; i++) {
+      int type = readAmfType(data);
+      Object value = readAmfData(data, type);
+      if (value != null) {
+        list.add(value);
+      }
+    }
+    return list;
+  }
+
+  /**
+   * Read an object from an AMF encoded buffer.
+   *
+   * @param data The buffer from which to read.
+   * @return The value read from the buffer.
+   */
+  private static HashMap<String, Object> readAmfObject(ParsableByteArray data) {
+    HashMap<String, Object> array = new HashMap<>();
+    while (true) {
+      String key = readAmfString(data);
+      int type = readAmfType(data);
+      if (type == AMF_TYPE_END_MARKER) {
+        break;
+      }
+      Object value = readAmfData(data, type);
+      if (value != null) {
+        array.put(key, value);
+      }
+    }
+    return array;
+  }
+
+  /**
+   * Read an ECMA array from an AMF encoded buffer.
+   *
+   * @param data The buffer from which to read.
+   * @return The value read from the buffer.
+   */
+  private static HashMap<String, Object> readAmfEcmaArray(ParsableByteArray data) {
+    int count = data.readUnsignedIntToInt();
+    HashMap<String, Object> array = new HashMap<>(count);
+    for (int i = 0; i < count; i++) {
+      String key = readAmfString(data);
+      int type = readAmfType(data);
+      Object value = readAmfData(data, type);
+      if (value != null) {
+        array.put(key, value);
+      }
+    }
+    return array;
+  }
+
+  /**
+   * Read a date from an AMF encoded buffer.
+   *
+   * @param data The buffer from which to read.
+   * @return The value read from the buffer.
+   */
+  private static Date readAmfDate(ParsableByteArray data) {
+    Date date = new Date((long) readAmfDouble(data).doubleValue());
+    data.skipBytes(2); // Skip reserved bytes.
+    return date;
+  }
+
+  @Nullable
+  private static Object readAmfData(ParsableByteArray data, int type) {
+    switch (type) {
+      case AMF_TYPE_NUMBER:
+        return readAmfDouble(data);
+      case AMF_TYPE_BOOLEAN:
+        return readAmfBoolean(data);
+      case AMF_TYPE_STRING:
+        return readAmfString(data);
+      case AMF_TYPE_OBJECT:
+        return readAmfObject(data);
+      case AMF_TYPE_ECMA_ARRAY:
+        return readAmfEcmaArray(data);
+      case AMF_TYPE_STRICT_ARRAY:
+        return readAmfStrictArray(data);
+      case AMF_TYPE_DATE:
+        return readAmfDate(data);
+      default:
+        // We don't log a warning because there are types that we knowingly don't support.
+        return null;
+    }
+  }
+}