Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 691 insertions, 0 deletions

diff --git a/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/drm/DefaultDrmSessionManager.java b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/drm/DefaultDrmSessionManager.java
new file mode 100644
index 0000000000..683862b99a
--- /dev/null
+++ b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/drm/DefaultDrmSessionManager.java
@@ -0,0 +1,691 @@
+/*
+ * 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.drm;
+
+import android.annotation.SuppressLint;
+import android.annotation.TargetApi;
+import android.os.Handler;
+import android.os.Looper;
+import android.os.Message;
+import androidx.annotation.IntDef;
+import androidx.annotation.Nullable;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.C;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.drm.DrmInitData.SchemeData;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.drm.DrmSession.DrmSessionException;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.drm.ExoMediaDrm.OnEventListener;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.upstream.DefaultLoadErrorHandlingPolicy;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.upstream.LoadErrorHandlingPolicy;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.Assertions;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.EventDispatcher;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.Log;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.Util;
+import java.lang.annotation.Documented;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+
+/** A {@link DrmSessionManager} that supports playbacks using {@link ExoMediaDrm}. */
+@TargetApi(18)
+public class DefaultDrmSessionManager<T extends ExoMediaCrypto> implements DrmSessionManager<T> {
+
+  /**
+   * Builder for {@link DefaultDrmSessionManager} instances.
+   *
+   * <p>See {@link #Builder} for the list of default values.
+   */
+  public static final class Builder {
+
+    private final HashMap<String, String> keyRequestParameters;
+    private UUID uuid;
+    private ExoMediaDrm.Provider<ExoMediaCrypto> exoMediaDrmProvider;
+    private boolean multiSession;
+    private int[] useDrmSessionsForClearContentTrackTypes;
+    private boolean playClearSamplesWithoutKeys;
+    private LoadErrorHandlingPolicy loadErrorHandlingPolicy;
+
+    /**
+     * Creates a builder with default values. The default values are:
+     *
+     * <ul>
+     *   <li>{@link #setKeyRequestParameters keyRequestParameters}: An empty map.
+     *   <li>{@link #setUuidAndExoMediaDrmProvider UUID}: {@link C#WIDEVINE_UUID}.
+     *   <li>{@link #setUuidAndExoMediaDrmProvider ExoMediaDrm.Provider}: {@link
+     *       FrameworkMediaDrm#DEFAULT_PROVIDER}.
+     *   <li>{@link #setMultiSession multiSession}: {@code false}.
+     *   <li>{@link #setUseDrmSessionsForClearContent useDrmSessionsForClearContent}: No tracks.
+     *   <li>{@link #setPlayClearSamplesWithoutKeys playClearSamplesWithoutKeys}: {@code false}.
+     *   <li>{@link #setLoadErrorHandlingPolicy LoadErrorHandlingPolicy}: {@link
+     *       DefaultLoadErrorHandlingPolicy}.
+     * </ul>
+     */
+    @SuppressWarnings("unchecked")
+    public Builder() {
+      keyRequestParameters = new HashMap<>();
+      uuid = C.WIDEVINE_UUID;
+      exoMediaDrmProvider = (ExoMediaDrm.Provider) FrameworkMediaDrm.DEFAULT_PROVIDER;
+      loadErrorHandlingPolicy = new DefaultLoadErrorHandlingPolicy();
+      useDrmSessionsForClearContentTrackTypes = new int[0];
+    }
+
+    /**
+     * Sets the key request parameters to pass as the last argument to {@link
+     * ExoMediaDrm#getKeyRequest(byte[], List, int, HashMap)}.
+     *
+     * <p>Custom data for PlayReady should be set under {@link #PLAYREADY_CUSTOM_DATA_KEY}.
+     *
+     * @param keyRequestParameters A map with parameters.
+     * @return This builder.
+     */
+    public Builder setKeyRequestParameters(Map<String, String> keyRequestParameters) {
+      this.keyRequestParameters.clear();
+      this.keyRequestParameters.putAll(Assertions.checkNotNull(keyRequestParameters));
+      return this;
+    }
+
+    /**
+     * Sets the UUID of the DRM scheme and the {@link ExoMediaDrm.Provider} to use.
+     *
+     * @param uuid The UUID of the DRM scheme.
+     * @param exoMediaDrmProvider The {@link ExoMediaDrm.Provider}.
+     * @return This builder.
+     */
+    @SuppressWarnings({"rawtypes", "unchecked"})
+    public Builder setUuidAndExoMediaDrmProvider(
+        UUID uuid, ExoMediaDrm.Provider exoMediaDrmProvider) {
+      this.uuid = Assertions.checkNotNull(uuid);
+      this.exoMediaDrmProvider = Assertions.checkNotNull(exoMediaDrmProvider);
+      return this;
+    }
+
+    /**
+     * Sets whether this session manager is allowed to acquire multiple simultaneous sessions.
+     *
+     * <p>Users should pass false when a single key request will obtain all keys required to decrypt
+     * the associated content. {@code multiSession} is required when content uses key rotation.
+     *
+     * @param multiSession Whether this session manager is allowed to acquire multiple simultaneous
+     *     sessions.
+     * @return This builder.
+     */
+    public Builder setMultiSession(boolean multiSession) {
+      this.multiSession = multiSession;
+      return this;
+    }
+
+    /**
+     * Sets whether this session manager should attach {@link DrmSession DrmSessions} to the clear
+     * sections of the media content.
+     *
+     * <p>Using {@link DrmSession DrmSessions} for clear content avoids the recreation of decoders
+     * when transitioning between clear and encrypted sections of content.
+     *
+     * @param useDrmSessionsForClearContentTrackTypes The track types ({@link C#TRACK_TYPE_AUDIO}
+     *     and/or {@link C#TRACK_TYPE_VIDEO}) for which to use a {@link DrmSession} regardless of
+     *     whether the content is clear or encrypted.
+     * @return This builder.
+     * @throws IllegalArgumentException If {@code useDrmSessionsForClearContentTrackTypes} contains
+     *     track types other than {@link C#TRACK_TYPE_AUDIO} and {@link C#TRACK_TYPE_VIDEO}.
+     */
+    public Builder setUseDrmSessionsForClearContent(
+        int... useDrmSessionsForClearContentTrackTypes) {
+      for (int trackType : useDrmSessionsForClearContentTrackTypes) {
+        Assertions.checkArgument(
+            trackType == C.TRACK_TYPE_VIDEO || trackType == C.TRACK_TYPE_AUDIO);
+      }
+      this.useDrmSessionsForClearContentTrackTypes =
+          useDrmSessionsForClearContentTrackTypes.clone();
+      return this;
+    }
+
+    /**
+     * Sets whether clear samples within protected content should be played when keys for the
+     * encrypted part of the content have yet to be loaded.
+     *
+     * @param playClearSamplesWithoutKeys Whether clear samples within protected content should be
+     *     played when keys for the encrypted part of the content have yet to be loaded.
+     * @return This builder.
+     */
+    public Builder setPlayClearSamplesWithoutKeys(boolean playClearSamplesWithoutKeys) {
+      this.playClearSamplesWithoutKeys = playClearSamplesWithoutKeys;
+      return this;
+    }
+
+    /**
+     * Sets the {@link LoadErrorHandlingPolicy} for key and provisioning requests.
+     *
+     * @param loadErrorHandlingPolicy A {@link LoadErrorHandlingPolicy}.
+     * @return This builder.
+     */
+    public Builder setLoadErrorHandlingPolicy(LoadErrorHandlingPolicy loadErrorHandlingPolicy) {
+      this.loadErrorHandlingPolicy = Assertions.checkNotNull(loadErrorHandlingPolicy);
+      return this;
+    }
+
+    /** Builds a {@link DefaultDrmSessionManager} instance. */
+    public DefaultDrmSessionManager<ExoMediaCrypto> build(MediaDrmCallback mediaDrmCallback) {
+      return new DefaultDrmSessionManager<>(
+          uuid,
+          exoMediaDrmProvider,
+          mediaDrmCallback,
+          keyRequestParameters,
+          multiSession,
+          useDrmSessionsForClearContentTrackTypes,
+          playClearSamplesWithoutKeys,
+          loadErrorHandlingPolicy);
+    }
+  }
+
+  /**
+   * Signals that the {@link DrmInitData} passed to {@link #acquireSession} does not contain does
+   * not contain scheme data for the required UUID.
+   */
+  public static final class MissingSchemeDataException extends Exception {
+
+    private MissingSchemeDataException(UUID uuid) {
+      super("Media does not support uuid: " + uuid);
+    }
+  }
+
+  /**
+   * A key for specifying PlayReady custom data in the key request parameters passed to {@link
+   * Builder#setKeyRequestParameters(Map)}.
+   */
+  public static final String PLAYREADY_CUSTOM_DATA_KEY = "PRCustomData";
+
+  /**
+   * Determines the action to be done after a session acquired. One of {@link #MODE_PLAYBACK},
+   * {@link #MODE_QUERY}, {@link #MODE_DOWNLOAD} or {@link #MODE_RELEASE}.
+   */
+  @Documented
+  @Retention(RetentionPolicy.SOURCE)
+  @IntDef({MODE_PLAYBACK, MODE_QUERY, MODE_DOWNLOAD, MODE_RELEASE})
+  public @interface Mode {}
+  /**
+   * Loads and refreshes (if necessary) a license for playback. Supports streaming and offline
+   * licenses.
+   */
+  public static final int MODE_PLAYBACK = 0;
+  /** Restores an offline license to allow its status to be queried. */
+  public static final int MODE_QUERY = 1;
+  /** Downloads an offline license or renews an existing one. */
+  public static final int MODE_DOWNLOAD = 2;
+  /** Releases an existing offline license. */
+  public static final int MODE_RELEASE = 3;
+  /** Number of times to retry for initial provisioning and key request for reporting error. */
+  public static final int INITIAL_DRM_REQUEST_RETRY_COUNT = 3;
+
+  private static final String TAG = "DefaultDrmSessionMgr";
+
+  private final UUID uuid;
+  private final ExoMediaDrm.Provider<T> exoMediaDrmProvider;
+  private final MediaDrmCallback callback;
+  private final HashMap<String, String> keyRequestParameters;
+  private final EventDispatcher<DefaultDrmSessionEventListener> eventDispatcher;
+  private final boolean multiSession;
+  private final int[] useDrmSessionsForClearContentTrackTypes;
+  private final boolean playClearSamplesWithoutKeys;
+  private final ProvisioningManagerImpl provisioningManagerImpl;
+  private final LoadErrorHandlingPolicy loadErrorHandlingPolicy;
+
+  private final List<DefaultDrmSession<T>> sessions;
+  private final List<DefaultDrmSession<T>> provisioningSessions;
+
+  private int prepareCallsCount;
+  @Nullable private ExoMediaDrm<T> exoMediaDrm;
+  @Nullable private DefaultDrmSession<T> placeholderDrmSession;
+  @Nullable private DefaultDrmSession<T> noMultiSessionDrmSession;
+  @Nullable private Looper playbackLooper;
+  private int mode;
+  @Nullable private byte[] offlineLicenseKeySetId;
+
+  /* package */ volatile @Nullable MediaDrmHandler mediaDrmHandler;
+
+  /**
+   * @param uuid The UUID of the drm scheme.
+   * @param exoMediaDrm An underlying {@link ExoMediaDrm} for use by the manager.
+   * @param callback Performs key and provisioning requests.
+   * @param keyRequestParameters An optional map of parameters to pass as the last argument to
+   *     {@link ExoMediaDrm#getKeyRequest(byte[], List, int, HashMap)}. May be null.
+   * @deprecated Use {@link Builder} instead.
+   */
+  @SuppressWarnings("deprecation")
+  @Deprecated
+  public DefaultDrmSessionManager(
+      UUID uuid,
+      ExoMediaDrm<T> exoMediaDrm,
+      MediaDrmCallback callback,
+      @Nullable HashMap<String, String> keyRequestParameters) {
+    this(
+        uuid,
+        exoMediaDrm,
+        callback,
+        keyRequestParameters == null ? new HashMap<>() : keyRequestParameters,
+        /* multiSession= */ false,
+        INITIAL_DRM_REQUEST_RETRY_COUNT);
+  }
+
+  /**
+   * @param uuid The UUID of the drm scheme.
+   * @param exoMediaDrm An underlying {@link ExoMediaDrm} for use by the manager.
+   * @param callback Performs key and provisioning requests.
+   * @param keyRequestParameters An optional map of parameters to pass as the last argument to
+   *     {@link ExoMediaDrm#getKeyRequest(byte[], List, int, HashMap)}. May be null.
+   * @param multiSession A boolean that specify whether multiple key session support is enabled.
+   *     Default is false.
+   * @deprecated Use {@link Builder} instead.
+   */
+  @Deprecated
+  public DefaultDrmSessionManager(
+      UUID uuid,
+      ExoMediaDrm<T> exoMediaDrm,
+      MediaDrmCallback callback,
+      @Nullable HashMap<String, String> keyRequestParameters,
+      boolean multiSession) {
+    this(
+        uuid,
+        exoMediaDrm,
+        callback,
+        keyRequestParameters == null ? new HashMap<>() : keyRequestParameters,
+        multiSession,
+        INITIAL_DRM_REQUEST_RETRY_COUNT);
+  }
+
+  /**
+   * @param uuid The UUID of the drm scheme.
+   * @param exoMediaDrm An underlying {@link ExoMediaDrm} for use by the manager.
+   * @param callback Performs key and provisioning requests.
+   * @param keyRequestParameters An optional map of parameters to pass as the last argument to
+   *     {@link ExoMediaDrm#getKeyRequest(byte[], List, int, HashMap)}. May be null.
+   * @param multiSession A boolean that specify whether multiple key session support is enabled.
+   *     Default is false.
+   * @param initialDrmRequestRetryCount The number of times to retry for initial provisioning and
+   *     key request before reporting error.
+   * @deprecated Use {@link Builder} instead.
+   */
+  @Deprecated
+  public DefaultDrmSessionManager(
+      UUID uuid,
+      ExoMediaDrm<T> exoMediaDrm,
+      MediaDrmCallback callback,
+      @Nullable HashMap<String, String> keyRequestParameters,
+      boolean multiSession,
+      int initialDrmRequestRetryCount) {
+    this(
+        uuid,
+        new ExoMediaDrm.AppManagedProvider<>(exoMediaDrm),
+        callback,
+        keyRequestParameters == null ? new HashMap<>() : keyRequestParameters,
+        multiSession,
+        /* useDrmSessionsForClearContentTrackTypes= */ new int[0],
+        /* playClearSamplesWithoutKeys= */ false,
+        new DefaultLoadErrorHandlingPolicy(initialDrmRequestRetryCount));
+  }
+
+  // the constructor does not initialize fields: offlineLicenseKeySetId
+  @SuppressWarnings("nullness:initialization.fields.uninitialized")
+  private DefaultDrmSessionManager(
+      UUID uuid,
+      ExoMediaDrm.Provider<T> exoMediaDrmProvider,
+      MediaDrmCallback callback,
+      HashMap<String, String> keyRequestParameters,
+      boolean multiSession,
+      int[] useDrmSessionsForClearContentTrackTypes,
+      boolean playClearSamplesWithoutKeys,
+      LoadErrorHandlingPolicy loadErrorHandlingPolicy) {
+    Assertions.checkNotNull(uuid);
+    Assertions.checkArgument(!C.COMMON_PSSH_UUID.equals(uuid), "Use C.CLEARKEY_UUID instead");
+    this.uuid = uuid;
+    this.exoMediaDrmProvider = exoMediaDrmProvider;
+    this.callback = callback;
+    this.keyRequestParameters = keyRequestParameters;
+    this.eventDispatcher = new EventDispatcher<>();
+    this.multiSession = multiSession;
+    this.useDrmSessionsForClearContentTrackTypes = useDrmSessionsForClearContentTrackTypes;
+    this.playClearSamplesWithoutKeys = playClearSamplesWithoutKeys;
+    this.loadErrorHandlingPolicy = loadErrorHandlingPolicy;
+    provisioningManagerImpl = new ProvisioningManagerImpl();
+    mode = MODE_PLAYBACK;
+    sessions = new ArrayList<>();
+    provisioningSessions = new ArrayList<>();
+  }
+
+  /**
+   * Adds a {@link DefaultDrmSessionEventListener} to listen to drm session events.
+   *
+   * @param handler A handler to use when delivering events to {@code eventListener}.
+   * @param eventListener A listener of events.
+   */
+  public final void addListener(Handler handler, DefaultDrmSessionEventListener eventListener) {
+    eventDispatcher.addListener(handler, eventListener);
+  }
+
+  /**
+   * Removes a {@link DefaultDrmSessionEventListener} from the list of drm session event listeners.
+   *
+   * @param eventListener The listener to remove.
+   */
+  public final void removeListener(DefaultDrmSessionEventListener eventListener) {
+    eventDispatcher.removeListener(eventListener);
+  }
+
+  /**
+   * Sets the mode, which determines the role of sessions acquired from the instance. This must be
+   * called before {@link #acquireSession(Looper, DrmInitData)} or {@link
+   * #acquirePlaceholderSession} is called.
+   *
+   * <p>By default, the mode is {@link #MODE_PLAYBACK} and a streaming license is requested when
+   * required.
+   *
+   * <p>{@code mode} must be one of these:
+   *
+   * <ul>
+   *   <li>{@link #MODE_PLAYBACK}: If {@code offlineLicenseKeySetId} is null, a streaming license is
+   *       requested otherwise the offline license is restored.
+   *   <li>{@link #MODE_QUERY}: {@code offlineLicenseKeySetId} can not be null. The offline license
+   *       is restored.
+   *   <li>{@link #MODE_DOWNLOAD}: If {@code offlineLicenseKeySetId} is null, an offline license is
+   *       requested otherwise the offline license is renewed.
+   *   <li>{@link #MODE_RELEASE}: {@code offlineLicenseKeySetId} can not be null. The offline
+   *       license is released.
+   * </ul>
+   *
+   * @param mode The mode to be set.
+   * @param offlineLicenseKeySetId The key set id of the license to be used with the given mode.
+   */
+  public void setMode(@Mode int mode, @Nullable byte[] offlineLicenseKeySetId) {
+    Assertions.checkState(sessions.isEmpty());
+    if (mode == MODE_QUERY || mode == MODE_RELEASE) {
+      Assertions.checkNotNull(offlineLicenseKeySetId);
+    }
+    this.mode = mode;
+    this.offlineLicenseKeySetId = offlineLicenseKeySetId;
+  }
+
+  // DrmSessionManager implementation.
+
+  @Override
+  public final void prepare() {
+    if (prepareCallsCount++ == 0) {
+      Assertions.checkState(exoMediaDrm == null);
+      exoMediaDrm = exoMediaDrmProvider.acquireExoMediaDrm(uuid);
+      exoMediaDrm.setOnEventListener(new MediaDrmEventListener());
+    }
+  }
+
+  @Override
+  public final void release() {
+    if (--prepareCallsCount == 0) {
+      Assertions.checkNotNull(exoMediaDrm).release();
+      exoMediaDrm = null;
+    }
+  }
+
+  @Override
+  public boolean canAcquireSession(DrmInitData drmInitData) {
+    if (offlineLicenseKeySetId != null) {
+      // An offline license can be restored so a session can always be acquired.
+      return true;
+    }
+    List<SchemeData> schemeDatas = getSchemeDatas(drmInitData, uuid, true);
+    if (schemeDatas.isEmpty()) {
+      if (drmInitData.schemeDataCount == 1 && drmInitData.get(0).matches(C.COMMON_PSSH_UUID)) {
+        // Assume scheme specific data will be added before the session is opened.
+        Log.w(
+            TAG, "DrmInitData only contains common PSSH SchemeData. Assuming support for: " + uuid);
+      } else {
+        // No data for this manager's scheme.
+        return false;
+      }
+    }
+    String schemeType = drmInitData.schemeType;
+    if (schemeType == null || C.CENC_TYPE_cenc.equals(schemeType)) {
+      // If there is no scheme information, assume patternless AES-CTR.
+      return true;
+    } else if (C.CENC_TYPE_cbc1.equals(schemeType)
+        || C.CENC_TYPE_cbcs.equals(schemeType)
+        || C.CENC_TYPE_cens.equals(schemeType)) {
+      // API support for AES-CBC and pattern encryption was added in API 24. However, the
+      // implementation was not stable until API 25.
+      return Util.SDK_INT >= 25;
+    }
+    // Unknown schemes, assume one of them is supported.
+    return true;
+  }
+
+  @Override
+  @Nullable
+  public DrmSession<T> acquirePlaceholderSession(Looper playbackLooper, int trackType) {
+    assertExpectedPlaybackLooper(playbackLooper);
+    ExoMediaDrm<T> exoMediaDrm = Assertions.checkNotNull(this.exoMediaDrm);
+    boolean avoidPlaceholderDrmSessions =
+        FrameworkMediaCrypto.class.equals(exoMediaDrm.getExoMediaCryptoType())
+            && FrameworkMediaCrypto.WORKAROUND_DEVICE_NEEDS_KEYS_TO_CONFIGURE_CODEC;
+    // Avoid attaching a session to sparse formats.
+    if (avoidPlaceholderDrmSessions
+        || Util.linearSearch(useDrmSessionsForClearContentTrackTypes, trackType) == C.INDEX_UNSET
+        || exoMediaDrm.getExoMediaCryptoType() == null) {
+      return null;
+    }
+    maybeCreateMediaDrmHandler(playbackLooper);
+    if (placeholderDrmSession == null) {
+      DefaultDrmSession<T> placeholderDrmSession =
+          createNewDefaultSession(
+              /* schemeDatas= */ Collections.emptyList(), /* isPlaceholderSession= */ true);
+      sessions.add(placeholderDrmSession);
+      this.placeholderDrmSession = placeholderDrmSession;
+    }
+    placeholderDrmSession.acquire();
+    return placeholderDrmSession;
+  }
+
+  @Override
+  public DrmSession<T> acquireSession(Looper playbackLooper, DrmInitData drmInitData) {
+    assertExpectedPlaybackLooper(playbackLooper);
+    maybeCreateMediaDrmHandler(playbackLooper);
+
+    @Nullable List<SchemeData> schemeDatas = null;
+    if (offlineLicenseKeySetId == null) {
+      schemeDatas = getSchemeDatas(drmInitData, uuid, false);
+      if (schemeDatas.isEmpty()) {
+        final MissingSchemeDataException error = new MissingSchemeDataException(uuid);
+        eventDispatcher.dispatch(listener -> listener.onDrmSessionManagerError(error));
+        return new ErrorStateDrmSession<>(new DrmSessionException(error));
+      }
+    }
+
+    @Nullable DefaultDrmSession<T> session;
+    if (!multiSession) {
+      session = noMultiSessionDrmSession;
+    } else {
+      // Only use an existing session if it has matching init data.
+      session = null;
+      for (DefaultDrmSession<T> existingSession : sessions) {
+        if (Util.areEqual(existingSession.schemeDatas, schemeDatas)) {
+          session = existingSession;
+          break;
+        }
+      }
+    }
+
+    if (session == null) {
+      // Create a new session.
+      session = createNewDefaultSession(schemeDatas, /* isPlaceholderSession= */ false);
+      if (!multiSession) {
+        noMultiSessionDrmSession = session;
+      }
+      sessions.add(session);
+    }
+    session.acquire();
+    return session;
+  }
+
+  @Override
+  @Nullable
+  public Class<T> getExoMediaCryptoType(DrmInitData drmInitData) {
+    return canAcquireSession(drmInitData)
+        ? Assertions.checkNotNull(exoMediaDrm).getExoMediaCryptoType()
+        : null;
+  }
+
+  // Internal methods.
+
+  private void assertExpectedPlaybackLooper(Looper playbackLooper) {
+    Assertions.checkState(this.playbackLooper == null || this.playbackLooper == playbackLooper);
+    this.playbackLooper = playbackLooper;
+  }
+
+  private void maybeCreateMediaDrmHandler(Looper playbackLooper) {
+    if (mediaDrmHandler == null) {
+      mediaDrmHandler = new MediaDrmHandler(playbackLooper);
+    }
+  }
+
+  private DefaultDrmSession<T> createNewDefaultSession(
+      @Nullable List<SchemeData> schemeDatas, boolean isPlaceholderSession) {
+    Assertions.checkNotNull(exoMediaDrm);
+    // Placeholder sessions should always play clear samples without keys.
+    boolean playClearSamplesWithoutKeys = this.playClearSamplesWithoutKeys | isPlaceholderSession;
+    return new DefaultDrmSession<>(
+        uuid,
+        exoMediaDrm,
+        /* provisioningManager= */ provisioningManagerImpl,
+        /* releaseCallback= */ this::onSessionReleased,
+        schemeDatas,
+        mode,
+        playClearSamplesWithoutKeys,
+        isPlaceholderSession,
+        offlineLicenseKeySetId,
+        keyRequestParameters,
+        callback,
+        Assertions.checkNotNull(playbackLooper),
+        eventDispatcher,
+        loadErrorHandlingPolicy);
+  }
+
+  private void onSessionReleased(DefaultDrmSession<T> drmSession) {
+    sessions.remove(drmSession);
+    if (placeholderDrmSession == drmSession) {
+      placeholderDrmSession = null;
+    }
+    if (noMultiSessionDrmSession == drmSession) {
+      noMultiSessionDrmSession = null;
+    }
+    if (provisioningSessions.size() > 1 && provisioningSessions.get(0) == drmSession) {
+      // Other sessions were waiting for the released session to complete a provision operation.
+      // We need to have one of those sessions perform the provision operation instead.
+      provisioningSessions.get(1).provision();
+    }
+    provisioningSessions.remove(drmSession);
+  }
+
+  /**
+   * Extracts {@link SchemeData} instances suitable for the given DRM scheme {@link UUID}.
+   *
+   * @param drmInitData The {@link DrmInitData} from which to extract the {@link SchemeData}.
+   * @param uuid The UUID.
+   * @param allowMissingData Whether a {@link SchemeData} with null {@link SchemeData#data} may be
+   *     returned.
+   * @return The extracted {@link SchemeData} instances, or an empty list if no suitable data is
+   *     present.
+   */
+  private static List<SchemeData> getSchemeDatas(
+      DrmInitData drmInitData, UUID uuid, boolean allowMissingData) {
+    // Look for matching scheme data (matching the Common PSSH box for ClearKey).
+    List<SchemeData> matchingSchemeDatas = new ArrayList<>(drmInitData.schemeDataCount);
+    for (int i = 0; i < drmInitData.schemeDataCount; i++) {
+      SchemeData schemeData = drmInitData.get(i);
+      boolean uuidMatches =
+          schemeData.matches(uuid)
+              || (C.CLEARKEY_UUID.equals(uuid) && schemeData.matches(C.COMMON_PSSH_UUID));
+      if (uuidMatches && (schemeData.data != null || allowMissingData)) {
+        matchingSchemeDatas.add(schemeData);
+      }
+    }
+    return matchingSchemeDatas;
+  }
+
+  @SuppressLint("HandlerLeak")
+  private class MediaDrmHandler extends Handler {
+
+    public MediaDrmHandler(Looper looper) {
+      super(looper);
+    }
+
+    @Override
+    public void handleMessage(Message msg) {
+      byte[] sessionId = (byte[]) msg.obj;
+      if (sessionId == null) {
+        // The event is not associated with any particular session.
+        return;
+      }
+      for (DefaultDrmSession<T> session : sessions) {
+        if (session.hasSessionId(sessionId)) {
+          session.onMediaDrmEvent(msg.what);
+          return;
+        }
+      }
+    }
+  }
+
+  private class ProvisioningManagerImpl implements DefaultDrmSession.ProvisioningManager<T> {
+    @Override
+    public void provisionRequired(DefaultDrmSession<T> session) {
+      if (provisioningSessions.contains(session)) {
+        // The session has already requested provisioning.
+        return;
+      }
+      provisioningSessions.add(session);
+      if (provisioningSessions.size() == 1) {
+        // This is the first session requesting provisioning, so have it perform the operation.
+        session.provision();
+      }
+    }
+
+    @Override
+    public void onProvisionCompleted() {
+      for (DefaultDrmSession<T> session : provisioningSessions) {
+        session.onProvisionCompleted();
+      }
+      provisioningSessions.clear();
+    }
+
+    @Override
+    public void onProvisionError(Exception error) {
+      for (DefaultDrmSession<T> session : provisioningSessions) {
+        session.onProvisionError(error);
+      }
+      provisioningSessions.clear();
+    }
+  }
+
+  private class MediaDrmEventListener implements OnEventListener<T> {
+
+    @Override
+    public void onEvent(
+        ExoMediaDrm<? extends T> md,
+        @Nullable byte[] sessionId,
+        int event,
+        int extra,
+        @Nullable byte[] data) {
+      Assertions.checkNotNull(mediaDrmHandler).obtainMessage(event, sessionId).sendToTarget();
+    }
+  }
+}