Update CDM interface and add clear key CDM.

webkit/media/crypto/clear_key_cdm.h

+// Copyright (c) 2012 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 WEBKIT_MEDIA_CRYPTO_CLEAR_KEY_CDM_H_
+#define WEBKIT_MEDIA_CRYPTO_CLEAR_KEY_CDM_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/memory/ref_counted.h"
+#include "media/base/decryptor_client.h"
+#include "media/crypto/aes_decryptor.h"
+#include "webkit/media/crypto/content_decryption_module.h"
+
+namespace media {
+class DecoderBuffer;
+}
+
+namespace webkit_media {
+
+// ClearKey implementation of the cdm::ContentDecryptionModule interface.
+// This implementation assumes that all method calls are made subsequently.

[ddorwin, 2012/08/16 05:00:35]

subsequently doesn't seem right. Were you thinking sequentially? That doesn't
seem right either.
"This class is not thread-safe."?

[xhwang, 2012/08/16 17:19:01]

I believe it's thread-safe now. Remove this comment. But yes, I meant
sequentially :)

+// Simultaneous method calls are not supported.

[ddorwin, 2012/08/16 05:00:35]

Is this still accurate? Is it just the session management calls that are not
thread safe? It looks like Decrypt is probably thread-safe now assuming
AesDecryptor is (for key access).

[xhwang, 2012/08/16 17:19:01]

It should be thread safe now.

+class ClearKeyCdm : public cdm::ContentDecryptionModule {
+ public:
+  ClearKeyCdm();
+  virtual ~ClearKeyCdm();
+
+  // ContentDecryptionModule implementation.
+  virtual Status GenerateKeyRequest(const uint8_t* init_data,
+                                    int init_data_size,
+                                    char** session_id,
+                                    int* session_id_size,
+                                    uint8_t** key_request,
+                                    int* key_request_size,
+                                    char** default_url,
+                                    int* default_url_size) OVERRIDE;
+
+  virtual Status AddKey(const char* session_id,
+                        int session_id_size,
+                        const uint8_t* key,
+                        int key_size) OVERRIDE;
+
+  virtual Status CancelKeyRequest(const char* session_id,
+                                  int session_id_size) OVERRIDE;
+
+  virtual Status Decrypt(const char* session_id,
+                         int session_id_size,
+                         const cdm::InputBuffer& encrypted_buffer,
+                         cdm::OutputBuffer* decrypted_buffer) OVERRIDE;
+
+ private:
+  class Client : public media::DecryptorClient {
+   public:
+    enum Status {
+      kKeyAdded,
+      kKeyError,
+      kKeyMessage,
+      kNeedKey
+    };
+
+    Client();
+    virtual ~Client();
+
+    Status status() { return status_; }
+    const std::string& session_id() { return session_id_; }
+    const uint8* key_message() { return key_message_.get(); }
+    int key_message_length() { return key_message_length_; }
+    const std::string& default_url() { return default_url_; }
+
+    // Resets the Client to a clean state.
+    void Reset();
+
+    // media::DecryptorClient implementation.
+    virtual void KeyAdded(const std::string& key_system,
+                          const std::string& session_id) OVERRIDE;
+    virtual void KeyError(const std::string& key_system,
+                          const std::string& session_id,
+                          media::Decryptor::KeyError error_code,
+                          int system_code) OVERRIDE;
+    virtual void KeyMessage(const std::string& key_system,
+                            const std::string& session_id,
+                            scoped_array<uint8> message,
+                            int message_length,
+                            const std::string& default_url) OVERRIDE;
+    virtual void NeedKey(const std::string& key_system,
+                         const std::string& session_id,
+                         scoped_array<uint8> init_data,
+                         int init_data_length) OVERRIDE;
+
+   private:
+    Status status_;
+    std::string session_id_;
+    scoped_array<uint8> key_message_;
+    int key_message_length_;
+    std::string default_url_;
+  };
+
+  Client client_;
+  media::AesDecryptor decryptor_;
+};
+
+}  // namespace webkit_media
+
+#endif  // WEBKIT_MEDIA_CRYPTO_CLEAR_KEY_CDM_H_