Separate MediaKeys interface from Decryptor interface.

media/base/media_keys.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_MEDIA_KEYS_H_
+#define MEDIA_BASE_MEDIA_KEYS_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/callback.h"
+#include "base/memory/scoped_ptr.h"
+#include "media/base/media_export.h"
+
+namespace media {
+
+// Performs media key operations.
+//
+// All key operations are called on the renderer thread. Therefore, these calls
+// should be fast and nonblocking; key events should be fired asynchronously.
+class MEDIA_EXPORT MediaKeys {
+ public:
+  // Reported to UMA, so never reuse a value!
+  // Must be kept in sync with WebKit::WebMediaPlayerClient::MediaKeyErrorCode
+  // (enforced in webmediaplayer_impl.cc).
+  enum KeyError {
+    kUnknownError = 1,
+    kClientError,
+    kServiceError,

[ddorwin, 2013/05/24 20:39:12]

At some point, we should comment out this one and the rest until the errors are
finalized. We only use the first two so far.

[xhwang, 2013/05/24 23:15:56]

ok

+    kOutputError,
+    kHardwareChangeError,
+    kDomainError,
+    kMaxKeyError  // Must be last and greater than any legit value.
+  };
+
+  MediaKeys();
+  virtual ~MediaKeys();
+
+  // Generates a key request for the |key_system| with |type| and
+  // |init_data| provided.
+  // Returns true if generating key request succeeded, false otherwise.
+  // Note: AddKey() and CancelKeyRequest() should only be called after
+  // GenerateKeyRequest() returns true.
+  virtual bool GenerateKeyRequest(const std::string& key_system,
+                                  const std::string& type,
+                                  const uint8* init_data,
+                                  int init_data_length) = 0;
+
+  // Adds a |key| to the |key_system|. The |key| is not limited to a decryption
+  // key. It can be any data that the key system accepts, such as a license.
+  // If multiple calls of this function set different keys for the same
+  // key ID, the older key will be replaced by the newer key.
+  virtual void AddKey(const std::string& key_system,
+                      const uint8* key, int key_length,
+                      const uint8* init_data, int init_data_length,
+                      const std::string& session_id) = 0;
+
+  // Cancels the key request specified by |session_id|.
+  virtual void CancelKeyRequest(const std::string& key_system,
+                                const std::string& session_id) = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(MediaKeys);
+};
+
+// Key event callbacks. See the spec for details:
+// http://dvcs.w3.org/hg/html-media/raw-file/eme-v0.1b/encrypted-media/encrypted-media.html#event-summary
+typedef base::Callback<void(const std::string& key_system,
+                            const std::string& session_id)> KeyAddedCB;
+
+typedef base::Callback<void(const std::string& key_system,
+                            const std::string& session_id,
+                            media::MediaKeys::KeyError error_code,
+                            int system_code)> KeyErrorCB;
+
+typedef base::Callback<void(const std::string& key_system,
+                            const std::string& session_id,
+                            const std::string& message,
+                            const std::string& default_url)> KeyMessageCB;
+
+typedef base::Callback<void(const std::string& key_system,
+                            const std::string& session_id,
+                            const std::string& type,
+                            scoped_ptr<uint8[]> init_data,
+                            int init_data_size)> NeedKeyCB;
+
+}  // namespace media
+
+#endif  // MEDIA_BASE_MEDIA_KEYS_H_