Add CdmWrapper to support multiple CDM versions in CdmAdapter.

media/cdm/ppapi/cdm_adapter.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 MEDIA_CDM_PPAPI_CDM_ADAPTER_H_
+#define MEDIA_CDM_PPAPI_CDM_ADAPTER_H_
+
+#include "base/basictypes.h"
+#include "media/cdm/ppapi/api/content_decryption_module.h"
+#include "media/cdm/ppapi/cdm_helpers.h"
+#include "ppapi/cpp/logging.h"
+
+namespace media {
+
+// CdmAdapter wraps different versions of ContentDecryptionModule interfaces and
+// exposes a common interface to the caller.
+//
+// The caller should call CdmAdapter::Create() to create a CDM instance.
+// CdmAdapter will first try to create a CDM instance that supports the latest
+// CDM interface (i.e. ContentDecryptionModule). If such an instance cannot be
+// created (e.g. an older CDM was loaded), CdmAdapter will try to create a CDM
+// that supports an older version of CDM interface (e.g.
+// ContentDecryptionModule_*). Internally CdmAdapter converts the CdmAdapter
+// calls to corresponding ContentDecryptionModule calls.
+//
+// Note that CdmAdapter interface always reflects the latest state of content
+// decryption related PPAPI APIs (e.g. pp::ContentDecryptor_Private).
+//
+// Since this file is highly templated and default implementations are short
+// (just a shim layer in most cases), everything is done in this header file.
+class CdmAdapter {
+ public:
+  static CdmAdapter* Create(const char* key_system,
+                            int key_system_size,
+                            GetCdmHostFunc get_cdm_host_func,
+                            void* user_data);
+
+  virtual ~CdmAdapter() {};
+
+  virtual cdm::Status GenerateKeyRequest(const char* type,
+                                         int type_size,
+                                         const uint8_t* init_data,
+                                         int init_data_size) = 0;
+  virtual cdm::Status AddKey(const char* session_id,
+                             int session_id_size,
+                             const uint8_t* key,
+                             int key_size,
+                             const uint8_t* key_id,
+                             int key_id_size) = 0;
+  virtual cdm::Status CancelKeyRequest(const char* session_id,
+                                       int session_id_size) = 0;
+  virtual void TimerExpired(void* context) = 0;
+  virtual cdm::Status Decrypt(const cdm::InputBuffer& encrypted_buffer,
+                              cdm::DecryptedBlock* decrypted_buffer) = 0;
+  virtual cdm::Status InitializeAudioDecoder(
+      const cdm::AudioDecoderConfig& audio_decoder_config) = 0;
+  virtual cdm::Status InitializeVideoDecoder(
+      const cdm::VideoDecoderConfig& video_decoder_config) = 0;
+  virtual void DeinitializeDecoder(cdm::StreamType decoder_type) = 0;
+  virtual void ResetDecoder(cdm::StreamType decoder_type) = 0;
+  virtual cdm::Status DecryptAndDecodeFrame(
+      const cdm::InputBuffer& encrypted_buffer,
+      cdm::VideoFrame* video_frame) = 0;
+  virtual cdm::Status DecryptAndDecodeSamples(
+      const cdm::InputBuffer& encrypted_buffer,
+      cdm::AudioFrames* audio_frames) = 0;
+  virtual void OnPlatformChallengeResponse(
+      const cdm::PlatformChallengeResponse& response) = 0;
+  virtual void OnQueryOutputProtectionStatus(
+      uint32_t link_mask,
+      uint32_t output_protection_mask) = 0;
+
+ protected:
+  CdmAdapter() {};
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(CdmAdapter);
+};
+
+// Template class that does the CdmAdapter -> CdmType conversion. Default
+// implementations are provided. Any methods that need special treatment should
+// be specialized.
+template <class CdmType>
+class CdmAdapterImpl : public CdmAdapter {
+ public:
+  static CdmAdapter* Create(const char* key_system,
+                            int key_system_size,
+                            GetCdmHostFunc get_cdm_host_func,
+                            void* user_data) {
+    void* cdm_instance = CreateCdmInstance(CdmType::kVersion,
+        key_system, key_system_size, get_cdm_host_func, user_data);
+    if (!cdm_instance)
+      return NULL;
+
+    return new CdmAdapterImpl<CdmType>(static_cast<CdmType*>(cdm_instance));
+  }
+
+  virtual ~CdmAdapterImpl() {
+    if (cdm_)
+      cdm_->Destroy();
+  }
+
+  virtual cdm::Status GenerateKeyRequest(const char* type,
+                                         int type_size,
+                                         const uint8_t* init_data,
+                                         int init_data_size) OVERRIDE {
+    return cdm_->GenerateKeyRequest(type, type_size, init_data, init_data_size);
+  }
+
+  virtual cdm::Status AddKey(const char* session_id,
+                             int session_id_size,
+                             const uint8_t* key,
+                             int key_size,
+                             const uint8_t* key_id,
+                             int key_id_size) OVERRIDE {
+    return cdm_->AddKey(
+        session_id, session_id_size, key, key_size, key_id, key_id_size);
+  }
+
+  virtual cdm::Status CancelKeyRequest(const char* session_id,
+                                       int session_id_size) OVERRIDE {
+    return cdm_->CancelKeyRequest(session_id, session_id_size);
+  }
+
+  virtual void TimerExpired(void* context) OVERRIDE {
+    cdm_->TimerExpired(context);
+  }
+
+  virtual cdm::Status Decrypt(const cdm::InputBuffer& encrypted_buffer,
+                              cdm::DecryptedBlock* decrypted_buffer) OVERRIDE {
+    return cdm_->Decrypt(encrypted_buffer, decrypted_buffer);
+  }
+
+  virtual cdm::Status InitializeAudioDecoder(
+      const cdm::AudioDecoderConfig& audio_decoder_config) OVERRIDE {
+    return cdm_->InitializeAudioDecoder(audio_decoder_config);
+  }
+
+  virtual cdm::Status InitializeVideoDecoder(
+      const cdm::VideoDecoderConfig& video_decoder_config) OVERRIDE {
+    return cdm_->InitializeVideoDecoder(video_decoder_config);
+  }
+
+  virtual void DeinitializeDecoder(cdm::StreamType decoder_type) OVERRIDE {
+    cdm_->DeinitializeDecoder(decoder_type);
+  }
+
+  virtual void ResetDecoder(cdm::StreamType decoder_type) OVERRIDE {
+    cdm_->ResetDecoder(decoder_type);
+  }
+
+  virtual cdm::Status DecryptAndDecodeFrame(
+      const cdm::InputBuffer& encrypted_buffer,
+      cdm::VideoFrame* video_frame) OVERRIDE {
+    return cdm_->DecryptAndDecodeFrame(encrypted_buffer, video_frame);
+  }
+
+  virtual cdm::Status DecryptAndDecodeSamples(
+      const cdm::InputBuffer& encrypted_buffer,
+      cdm::AudioFrames* audio_frames) OVERRIDE {
+    return cdm_->DecryptAndDecodeSamples(encrypted_buffer, audio_frames);
+  }
+
+  virtual void OnPlatformChallengeResponse(
+      const cdm::PlatformChallengeResponse& response) OVERRIDE {
+    cdm_->OnPlatformChallengeResponse(response);
+  }
+
+  virtual void OnQueryOutputProtectionStatus(
+      uint32_t link_mask,
+      uint32_t output_protection_mask) OVERRIDE {
+    cdm_->OnQueryOutputProtectionStatus(link_mask, output_protection_mask);
+  }
+
+ private:
+  CdmAdapterImpl(CdmType* cdm) : cdm_(cdm) {
+    PP_DCHECK(cdm_);
+  }
+
+  CdmType* cdm_;
+
+  DISALLOW_COPY_AND_ASSIGN(CdmAdapterImpl);
+};
+
+// Specializations for ContentDecryptionModule_1.
+
+template <> void CdmAdapterImpl<cdm::ContentDecryptionModule_1>::
+    OnPlatformChallengeResponse(
+        const cdm::PlatformChallengeResponse& response) {
+  PP_NOTREACHED();
+}
+
+template <> void CdmAdapterImpl<cdm::ContentDecryptionModule_1>::
+    OnQueryOutputProtectionStatus(uint32_t link_mask,
+                                  uint32_t output_protection_mask) {
+  PP_NOTREACHED();
+}
+
+template <> cdm::Status CdmAdapterImpl<cdm::ContentDecryptionModule_1>::
+    DecryptAndDecodeSamples(const cdm::InputBuffer& encrypted_buffer,
+                            cdm::AudioFrames* audio_frames) {
+  AudioFramesImpl audio_frames_1;
+  cdm::Status status =
+      cdm_->DecryptAndDecodeSamples(encrypted_buffer, &audio_frames_1);
+  if (status != cdm::kSuccess)
+    return status;
+
+  audio_frames->SetFrameBuffer(audio_frames_1.PassFrameBuffer());
+  audio_frames->SetFormat(cdm::kAudioFormatS16);
+  return cdm::kSuccess;
+}
+
+CdmAdapter* CdmAdapter::Create(const char* key_system,
+                               int key_system_size,
+                               GetCdmHostFunc get_cdm_host_func,
+                               void* user_data) {
+  // Try to create the CDM using the latest CDM interface version.
+  CdmAdapter* cdm_adapter =
+      CdmAdapterImpl<cdm::ContentDecryptionModule>::Create(
+          key_system, key_system_size, get_cdm_host_func, user_data);
+  if (cdm_adapter)
+    return cdm_adapter;
+
+  // Try to see if the CDM supports older version(s) of CDM interface(s).
+  cdm_adapter = CdmAdapterImpl<cdm::ContentDecryptionModule_1>::Create(
+      key_system, key_system_size, get_cdm_host_func, user_data);
+  return cdm_adapter;
+}
+
+}  // namespace media
+
+#endif  // MEDIA_CDM_PPAPI_CDM_ADAPTER_H_