Add Promises for EME (Chromium side)

content/renderer/media/crypto/proxy_decryptor.h

 // Copyright 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 CONTENT_RENDERER_MEDIA_CRYPTO_PROXY_DECRYPTOR_H_
 #define CONTENT_RENDERER_MEDIA_CRYPTO_PROXY_DECRYPTOR_H_
 
-#include <map>
-#include <set>
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
+#include "base/containers/hash_tables.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
-#include "base/synchronization/lock.h"
 #include "media/base/decryptor.h"
 #include "media/base/media_keys.h"
 
 #if defined(ENABLE_PEPPER_CDMS)
 #include "content/renderer/media/crypto/pepper_cdm_wrapper.h"
 #endif
 
 class GURL;
 
 namespace content {
 
 #if defined(OS_ANDROID)
 class RendererCdmManager;
 #endif  // defined(OS_ANDROID)
 
 // ProxyDecryptor is for EME v0.1b only. It should not be used for the WD API.
 // A decryptor proxy that creates a real decryptor object on demand and
 // forwards decryptor calls to it.
 //
-// Now that the Pepper API calls use session ID to match responses with
-// requests, this class maintains a mapping between session ID and web session
-// ID. Callers of this class expect web session IDs in the responses.
-// Session IDs are internal unique references to the session. Web session IDs
-// are the CDM generated ID for the session, and are what are visible to users.
-//
 // TODO(xhwang): Currently we don't support run-time switching among decryptor
 // objects. Fix this when needed.
 // TODO(xhwang): The ProxyDecryptor is not a Decryptor. Find a better name!
 class ProxyDecryptor {
  public:
   // These are similar to the callbacks in media_keys.h, but pass back the
   // web session ID rather than the internal session ID.
   typedef base::Callback<void(const std::string& session_id)> KeyAddedCB;
   typedef base::Callback<void(const std::string& session_id,
                               media::MediaKeys::KeyError error_code,
@@ skipping 30 matching lines @@
   // May only be called after InitializeCDM() succeeds.
   bool GenerateKeyRequest(const std::string& type,
                           const uint8* init_data,
                           int init_data_length);
   void AddKey(const uint8* key, int key_length,
               const uint8* init_data, int init_data_length,
               const std::string& session_id);
   void CancelKeyRequest(const std::string& session_id);
 
  private:
-  // Session_id <-> web_session_id map.
-  typedef std::map<uint32, std::string> SessionIdMap;
-
   // Helper function to create MediaKeys to handle the given |key_system|.
   scoped_ptr<media::MediaKeys> CreateMediaKeys(const std::string& key_system,
                                                const GURL& security_origin);
 
   // 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 GURL& default_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,
+                      media::MediaKeys::Exception exception_code,
+                      uint32 system_code,
+                      const std::string& error_message);
 
-  // Helper function to determine session_id for the provided |web_session_id|.
-  uint32 LookupSessionId(const std::string& web_session_id) const;
-
-  // Helper function to determine web_session_id for the provided |session_id|.
-  // The returned web_session_id is only valid on the main thread, and should be
-  // stored by copy.
-  const std::string& LookupWebSessionId(uint32 session_id) const;
+  // Called when a session is actually created or loaded.
+  void SetSessionId(bool persistent, const std::string& web_session_id);
 
 #if defined(ENABLE_PEPPER_CDMS)
   // Callback to create the Pepper plugin.
   CreatePepperCdmCB create_pepper_cdm_cb_;
 #elif defined(OS_ANDROID)
   RendererCdmManager* manager_;
   int cdm_id_;
 #endif  // defined(ENABLE_PEPPER_CDMS)
 
   // The real MediaKeys that manages key operations for the ProxyDecryptor.
   scoped_ptr<media::MediaKeys> media_keys_;
 
   // Callbacks for firing key events.
   KeyAddedCB key_added_cb_;
   KeyErrorCB key_error_cb_;
   KeyMessageCB key_message_cb_;
 
-  // Session IDs are used to uniquely track sessions so that CDM callbacks
-  // can get mapped to the correct session ID. Session ID should be unique
-  // per renderer process for debugging purposes.
-  static uint32 next_session_id_;
-
-  SessionIdMap sessions_;
-
-  std::set<uint32> persistent_sessions_;
+  // Keep track of both persistent and non-persistent sessions.
+  base::hash_map<std::string, bool> active_sessions_;
 
   bool is_clear_key_;
 
   // NOTE: Weak pointers must be invalidated before all other member variables.
   base::WeakPtrFactory<ProxyDecryptor> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ProxyDecryptor);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_CRYPTO_PROXY_DECRYPTOR_H_