chromium/media/base/cdm_context.h

// Copyright 2014 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_BASE_CDM_CONTEXT_H_
#define MEDIA_BASE_CDM_CONTEXT_H_

#include <optional>

#include "base/functional/callback.h"
#include "base/memory/scoped_refptr.h"
#include "base/unguessable_token.h"
#include "build/build_config.h"
#include "media/base/media_export.h"
#include "media/media_buildflags.h"

#if BUILDFLAG(IS_WIN)
#include "media/base/win/media_foundation_cdm_proxy.h"
#endif

#if BUILDFLAG(IS_CHROMEOS)
namespace chromeos {
class ChromeOsCdmContext;
}
#endif

namespace media {

class CallbackRegistration;
class Decryptor;
class MediaCryptoContext;

#if BUILDFLAG(IS_FUCHSIA)
class FuchsiaCdmContext;
#endif

// An interface representing the context that a media player needs from a
// content decryption module (CDM) to decrypt (and decode) encrypted buffers.
// Typically this will be passed to the media player (e.g. using SetCdm()).
//
// Lifetime: The returned raw pointers are only guaranteed to be valid when the
// CdmContext is alive, which is usually guaranteed by holding a CdmContextRef
// (see below).
//
// Thread Model: Since this interface is used in many different contexts (e.g.
// different processes or platforms), the thread model is not defined as part
// of this interface. Subclasses must ensure thread safety.
class MEDIA_EXPORT CdmContext { … };

// A reference holder to make sure the CdmContext is always valid as long as
// |this| is alive. Typically |this| will hold a reference (directly or
// indirectly) to the host, e.g. a ContentDecryptionModule.
// This class must be held on the same thread where the host lives. The raw
// CdmContext pointer returned by GetCdmContext() may be used on other threads
// if it's supported by the CdmContext implementation.
class MEDIA_EXPORT CdmContextRef { … };

}  // namespace media

#endif  // MEDIA_BASE_CDM_CONTEXT_H_