cdm_wrapper.h | Explore in Territory

// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef MEDIA_CDM_CDM_WRAPPER_H_
#define MEDIA_CDM_CDM_WRAPPER_H_

#include <stdint.h>

#include "base/check.h"
#include "base/feature_list.h"
#include "base/memory/raw_ptr.h"
#include "media/base/media_switches.h"
#include "media/cdm/api/content_decryption_module.h"
#include "media/cdm/cdm_helpers.h"
#include "media/cdm/supported_cdm_versions.h"

namespace media {

namespace {

cdm::VideoDecoderConfig_2 ToVideoDecoderConfig_2(
    const cdm::VideoDecoderConfig_3& config) { … }

}  // namespace

// Returns a pointer to the requested CDM upon success.
// Returns NULL if an error occurs or the requested |cdm_interface_version| or
// |key_system| is not supported or another error occurs.
// The caller should cast the returned pointer to the type matching
// |cdm_interface_version|.
// Caller retains ownership of arguments and must call Destroy() on the returned
// object.
CreateCdmFunc;

// CdmWrapper wraps different versions of ContentDecryptionModule interfaces and
// exposes a common interface to the caller.
//
// The caller should call CdmWrapper::Create() to create a CDM instance.
// CdmWrapper will first try to create a CDM instance that supports the latest
// CDM interface (ContentDecryptionModule). If such an instance cannot be
// created (e.g. an older CDM was loaded), CdmWrapper will try to create a CDM
// that supports an older version of CDM interface (e.g.
// ContentDecryptionModule_*). Internally CdmWrapper converts the CdmWrapper
// calls to corresponding ContentDecryptionModule calls.
//
// 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.
//
// TODO(crbug.com/41363203): After pepper CDM support is removed, this file can
// depend on media/ and we can clean this class up, e.g. pass in CdmConfig.
class CdmWrapper { … };

// Template class that does the CdmWrapper -> CdmInterface conversion. Default
// implementations are provided. Any methods that need special treatment should
// be specialized.
template <int CdmInterfaceVersion>
class CdmWrapperImpl : public CdmWrapper { … };

// Specialization for cdm::ContentDecryptionModule_10 methods.

template <>
cdm::Status CdmWrapperImpl<10>::InitializeVideoDecoder(
    const cdm::VideoDecoderConfig_3& video_decoder_config) { … }

// static
CdmWrapper* CdmWrapper::Create(CreateCdmFunc create_cdm_func,
                               const char* key_system,
                               uint32_t key_system_size,
                               GetCdmHostFunc get_cdm_host_func,
                               void* user_data) { … }

}  // namespace media

#endif  // MEDIA_CDM_CDM_WRAPPER_H_
chromium/media/cdm/cdm_wrapper.h
