Prepare MediaDrmBridge to work with MediaCodecPlayer

media/base/android/media_drm_bridge.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BASE_ANDROID_MEDIA_DRM_BRIDGE_H_
 #define MEDIA_BASE_ANDROID_MEDIA_DRM_BRIDGE_H_
 
 #include <jni.h>
 #include <string>
 #include <vector>
 
 #include "base/android/scoped_java_ref.h"
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
 #include "media/base/browser_cdm.h"
 #include "media/base/cdm_promise_adapter.h"
 #include "media/base/media_export.h"
 #include "media/cdm/player_tracker_impl.h"
 #include "url/gurl.h"
 
 class GURL;
 
 namespace media {
 
 class MediaPlayerManager;
 
 // This class provides DRM services for android EME implementation.
 class MEDIA_EXPORT MediaDrmBridge : public BrowserCdm {
  public:
   // TODO(ddorwin): These are specific to Widevine. http://crbug.com/459400
   enum SecurityLevel {
     SECURITY_LEVEL_NONE = 0,
     SECURITY_LEVEL_1 = 1,
     SECURITY_LEVEL_3 = 3,
   };
 
+  typedef scoped_ptr<base::android::ScopedJavaGlobalRef<jobject>> JavaObjectPtr;
+
   typedef base::Callback<void(bool)> ResetCredentialsCB;
 
+  // Notification called when MediaCrypto object is ready.
+  // Parameters:
+  // |media_crypto| - global reference to MediaCrypto object
+  // |needs_protected_surface| - true if protected surface is required.
+  typedef base::Callback<void(JavaObjectPtr media_crypto,
+                              bool needs_protected_surface)> MediaCryptoReadyCB;
+
   ~MediaDrmBridge() override;
 
+  void DeleteOnCorrectThread() override;
+
   // Checks whether MediaDRM is available.
   // All other static methods check IsAvailable() internally. There's no need
   // to check IsAvailable() explicitly before calling them.
   static bool IsAvailable();
 
   // Checks whether |key_system| is supported.
   static bool IsKeySystemSupported(const std::string& key_system);
 
   // Returns the list of the platform-supported key system names that
   // are not handled by Chrome explicitly.
   static std::vector<std::string> GetPlatformKeySystemNames();
 
   // Checks whether |key_system| is supported with |container_mime_type|.
   // |container_mime_type| must not be empty.
   static bool IsKeySystemSupportedWithType(
       const std::string& key_system,
       const std::string& container_mime_type);
 
   static bool RegisterMediaDrmBridge(JNIEnv* env);
 
   // Returns a MediaDrmBridge instance if |key_system| is supported, or a NULL
   // pointer otherwise.
   // TODO(xhwang): Is it okay not to update session expiration info?
-  static scoped_ptr<MediaDrmBridge> Create(
+  static scoped_ptr<MediaDrmBridge, BrowserCdmDeleter> Create(

[xhwang, 2015/09/29 17:28:23]

nit: here and throughout this file, use MediaDrmPtr?

[Tima Vaisburd, 2015/09/29 19:55:44]

I guess s/MediaDrmPtr/BrowserCdmPtr/

I think I can't, the caller wants to call SetSecurityLevel() on this pointer.
See the prior comment.

       const std::string& key_system,
       const SessionMessageCB& session_message_cb,
       const SessionClosedCB& session_closed_cb,
       const LegacySessionErrorCB& legacy_session_error_cb,
       const SessionKeysChangeCB& session_keys_change_cb,
       const SessionExpirationUpdateCB& session_expiration_update_cb);
 
   // Returns a MediaDrmBridge instance if |key_system| is supported, or a NULL
   // otherwise. No session callbacks are provided. This is used when we need to
   // use MediaDrmBridge without creating any sessions.
-  static scoped_ptr<MediaDrmBridge> CreateWithoutSessionSupport(
-      const std::string& key_system);
+  static scoped_ptr<MediaDrmBridge, BrowserCdmDeleter>
+  CreateWithoutSessionSupport(const std::string& key_system);
 
   // Returns true if |security_level| is successfully set, or false otherwise.
   // Call this function right after Create() and before any other calls.
   // Note:
   // - If this function is not called, the default security level of the device
   //   will be used.
   // - It's recommended to call this function only once on a MediaDrmBridge
   //   object. Calling this function multiples times may cause errors.
   bool SetSecurityLevel(SecurityLevel security_level);
 
@@ skipping 22 matching lines @@
   int RegisterPlayer(const base::Closure& new_key_cb,
                      const base::Closure& cdm_unset_cb) override;
   void UnregisterPlayer(int registration_id) override;
 
   // Returns a MediaCrypto object if it's already created. Returns a null object
   // otherwise.
   base::android::ScopedJavaLocalRef<jobject> GetMediaCrypto();
 
   // Sets callback which will be called when MediaCrypto is ready.
   // If |closure| is null, previously set callback will be cleared.
-  void SetMediaCryptoReadyCB(const base::Closure& closure);
+  void SetMediaCryptoReadyCB(const MediaCryptoReadyCB& closure);
 
-  // Called after a MediaCrypto object is created.
+  // Called by Java after a MediaCrypto object is created.
   void OnMediaCryptoReady(JNIEnv* env, jobject j_media_drm);
 
   // Callbacks to resolve the promise for |promise_id|.
   void OnPromiseResolved(JNIEnv* env, jobject j_media_drm, jint j_promise_id);
   void OnPromiseResolvedWithSession(JNIEnv* env,
                                     jobject j_media_drm,
                                     jint j_promise_id,
                                     jbyteArray j_session_id);
 
   // Callback to reject the promise for |promise_id| with |error_message|.
@@ skipping 47 matching lines @@
   // Reset the device credentials.
   void ResetDeviceCredentials(const ResetCredentialsCB& callback);
 
   // Called by the java object when credential reset is completed.
   void OnResetDeviceCredentialsCompleted(JNIEnv* env, jobject, bool success);
 
   // Helper function to determine whether a protected surface is needed for the
   // video playback.
   bool IsProtectedSurfaceRequired();
 
+  // We use this pointer when we post SetMediaCryptoReadyCB onto UI thread.
+  base::WeakPtr<MediaDrmBridge> WeakPtrForUIThread();

[qinmin, 2015/09/26 00:40:32]

is this ever being used?

[Tima Vaisburd, 2015/09/26 00:53:28]

Only in one place, in MediaCodecPlayer::SetCdm() in
https://codereview.chromium.org/1344133002/

For that matter, would it be better to move the changes in this file into that
CL?

+
  private:
   MediaDrmBridge(const std::vector<uint8>& scheme_uuid,
                  const SessionMessageCB& session_message_cb,
                  const SessionClosedCB& session_closed_cb,
                  const LegacySessionErrorCB& legacy_session_error_cb,
                  const SessionKeysChangeCB& session_keys_change_cb,
                  const SessionExpirationUpdateCB& session_expiration_update_cb);
 
   static bool IsSecureDecoderRequired(SecurityLevel security_level);
 
   // Get the security level of the media.
   SecurityLevel GetSecurityLevel();
 
+  // A helper method that calls a |player_tracker_| method on correct thread.
+  void NotifyNewKeyOnCorrectThread();
+
+  // A helper method that posts or runs |media_crypto_ready_cb_|.
+  void PostMediaCryptoReadyOnCorrectThread(const MediaCryptoReadyCB& cb,
+                                           bool always_post_on_ui_thread);
+
   // UUID of the key system.
   std::vector<uint8> scheme_uuid_;
 
   // Java MediaDrm instance.
   base::android::ScopedJavaGlobalRef<jobject> j_media_drm_;
 
   // Callbacks for firing session events.
   SessionMessageCB session_message_cb_;
   SessionClosedCB session_closed_cb_;
   LegacySessionErrorCB legacy_session_error_cb_;
   SessionKeysChangeCB session_keys_change_cb_;
   SessionExpirationUpdateCB session_expiration_update_cb_;
 
-  base::Closure media_crypto_ready_cb_;
+  MediaCryptoReadyCB media_crypto_ready_cb_;
 
   ResetCredentialsCB reset_credentials_cb_;
 
   PlayerTrackerImpl player_tracker_;
 
   CdmPromiseAdapter cdm_promise_adapter_;
 
+  // Object for posting tasks on UI thread.
+  scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner_;
+
+  // This flag is set when we use media thread for certain callbacks.
+  bool use_media_thread_;
+
+  // NOTE: Weak pointers must be invalidated before all other member variables.
+  base::WeakPtrFactory<MediaDrmBridge> media_weak_factory_;
+  base::WeakPtrFactory<MediaDrmBridge> ui_weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(MediaDrmBridge);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_ANDROID_MEDIA_DRM_BRIDGE_H_