Add Promises for EME (Chromium side)

content/renderer/media/cdm_session_adapter.h

 // Copyright 2014 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 CONTENT_RENDERER_MEDIA_CDM_SESSION_ADAPTER_H_
 #define CONTENT_RENDERER_MEDIA_CDM_SESSION_ADAPTER_H_
 
 #include <map>
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "media/base/media_keys.h"
+#include "media/base/media_keys_session_promise.h"
 #include "third_party/WebKit/public/platform/WebContentDecryptionModuleSession.h"
 
 #if defined(ENABLE_PEPPER_CDMS)
 #include "content/renderer/media/crypto/pepper_cdm_wrapper.h"
 #endif
 
 class GURL;
 
 namespace content {
 
 class WebContentDecryptionModuleSessionImpl;
 
 // Owns the CDM instance and makes calls from session objects to the CDM.
 // Forwards the session ID-based callbacks of the MediaKeys interface to the

[xhwang, 2014/05/05 20:46:42]

s/session/web session/

This seems a pretty big change. Can you put it in the CL description and explain
why we make this change?

Also, when we totally get rid of session ID, probably we can rename
web_session_id back to session_id?

[jrummell, 2014/05/08 23:37:45]

Done.

 // appropriate session object. Callers should hold references to this class
 // as long as they need the CDM instance.
 class CdmSessionAdapter : public base::RefCounted<CdmSessionAdapter> {
  public:
   CdmSessionAdapter();
 
   // Returns true on success.
   bool Initialize(
 #if defined(ENABLE_PEPPER_CDMS)
       const CreatePepperCdmCB& create_pepper_cdm_cb,
 #endif
       const std::string& key_system,
       const GURL& security_origin);
 
   // Creates a new session and adds it to the internal map. The caller owns the
-  // created session. RemoveSession() must be called when destroying it.
+  // created session.

[ddorwin, 2014/05/05 18:35:42]

Why was the following removed? Is it no longer true?
RemoveSession() must be called when destroying it.

[jrummell, 2014/05/08 23:37:45]

Added back (with explanation).

   WebContentDecryptionModuleSessionImpl* CreateSession(
       blink::WebContentDecryptionModuleSession::Client* client);
 
+  // Adds a session to the internal map. Called once the session is successfully
+  // initialized.
+  void RegisterSession(
+      const std::string& web_session_id,
+      base::WeakPtr<WebContentDecryptionModuleSessionImpl> session);
+
   // Removes a session from the internal map.
-  void RemoveSession(uint32 session_id);
+  void RemoveSession(const std::string& web_session_id);
 
-  // Initializes the session specified by |session_id| with the |content_type|
-  // and |init_data| provided.
-  void InitializeNewSession(uint32 session_id,
-                            const std::string& content_type,
+  // Initializes a session with the |init_data_type|, |init_data| and
+  // |session_type| provided. Takes ownership of |promise|.
+  void InitializeNewSession(const std::string& init_data_type,
                             const uint8* init_data,
-                            int init_data_length);
+                            int init_data_length,
+                            media::MediaKeys::SessionType session_type,
+                            scoped_ptr<media::MediaKeysSessionPromise> promise);
 
-  // Updates the session specified by |session_id| with |response|.
-  void UpdateSession(uint32 session_id,
+  // Updates the session specified by |web_session_id| with |response|.
+  // Takes ownership of |promise|.
+  void UpdateSession(const std::string& web_session_id,
                      const uint8* response,
-                     int response_length);
+                     int response_length,
+                     scoped_ptr<media::MediaKeysSessionPromise> promise);
 
-  // Releases the session specified by |session_id|.
-  void ReleaseSession(uint32 session_id);
+  // Releases the session specified by |web_session_id|.
+  // Takes ownership of |promise|.
+  void ReleaseSession(const std::string& web_session_id,
+                      scoped_ptr<media::MediaKeysSessionPromise> promise);
 
   // Returns the Decryptor associated with this CDM. May be NULL if no
   // Decryptor is associated with the MediaKeys object.
   // TODO(jrummell): Figure out lifetimes, as WMPI may still use the decryptor
   // after WebContentDecryptionModule is freed. http://crbug.com/330324
   media::Decryptor* GetDecryptor();
 
 #if defined(OS_ANDROID)
   // Returns the CDM ID associated with the |media_keys_|. May be kInvalidCdmId
   // if no CDM ID is associated.
   int GetCdmId() const;
 #endif
 
  private:
   friend class base::RefCounted<CdmSessionAdapter>;
-  typedef std::map<uint32, WebContentDecryptionModuleSessionImpl*> SessionMap;
+  typedef std::map<std::string,

[xhwang, 2014/05/05 20:46:42]

Since the key is now a string, we should use hash_map for better performance.

[jrummell, 2014/05/08 23:37:45]

Done.

+                   base::WeakPtr<WebContentDecryptionModuleSessionImpl> >
+      SessionMap;
 
   ~CdmSessionAdapter();
 
   // Callbacks for firing session events.
-  void OnSessionCreated(uint32 session_id, const std::string& web_session_id);
-  void OnSessionMessage(uint32 session_id,
+  void OnSessionMessage(const std::string& web_session_id,
                         const std::vector<uint8>& message,
                         const std::string& destination_url);
-  void OnSessionReady(uint32 session_id);
-  void OnSessionClosed(uint32 session_id);
-  void OnSessionError(uint32 session_id,
-                      media::MediaKeys::KeyError error_code,
-                      uint32 system_code);
+  void OnSessionReady(const std::string& web_session_id);
+  void OnSessionClosed(const std::string& web_session_id);
+  void OnSessionError(const std::string& web_session_id,
+                      const std::string& error_name,
+                      uint32 system_code,
+                      const std::string& error_message);
 
   // Helper function of the callbacks.
-  WebContentDecryptionModuleSessionImpl* GetSession(uint32 session_id);
-
-  // Session ID should be unique per renderer process for debugging purposes.
-  static uint32 next_session_id_;
+  WebContentDecryptionModuleSessionImpl* GetSession(
+      const std::string& web_session_id);
 
   scoped_ptr<media::MediaKeys> media_keys_;
 
   SessionMap sessions_;
 
 #if defined(OS_ANDROID)
   int cdm_id_;
 #endif
 
   // NOTE: Weak pointers must be invalidated before all other member variables.
   base::WeakPtrFactory<CdmSessionAdapter> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(CdmSessionAdapter);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_CDM_SESSION_ADAPTER_H_