chromium/third_party/blink/renderer/bindings/core/v8/script_cache_consumer.h

// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef THIRD_PARTY_BLINK_RENDERER_BINDINGS_CORE_V8_SCRIPT_CACHE_CONSUMER_H_
#define THIRD_PARTY_BLINK_RENDERER_BINDINGS_CORE_V8_SCRIPT_CACHE_CONSUMER_H_

#include "base/memory/scoped_refptr.h"
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/platform/heap/garbage_collected.h"
#include "third_party/blink/renderer/platform/heap/member.h"
#include "third_party/blink/renderer/platform/wtf/functional.h"
#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"
#include "v8/include/v8.h"

namespace base {
class SingleThreadTaskRunner;
}

namespace blink {

class CachedMetadata;
class ClassicScript;
class ScriptCacheConsumerClient;

// A V8 code cache consumer for a script's code cache, which consumes the code
// cache off-thread and notifies a given ScriptCacheConsumerClient once it has
// completed.
//
// ScriptCacheConsumer works on unchecked CachedMetadata speculatively, before
// the source is available. If CachedMetadataHandler::Check() fails later,
// the CachedMetadata on the CachedMetadataHandler will be cleared, and the
// result of this ScriptCacheConsumer will be dropped on TakeV8ConsumeTask() due
// to a CachedMetadata mismatch.
//
// The state of the ScriptCacheConsumer state is associated with a single
// CachedMetadata, but it is independent of the state of the corresponding
// ScriptResource or its CachedMetadataHandler. Thus, it's fine that one
// ClassicPendingScript for the ScriptResource can get a non-null
// ConsumeCodeCacheTask from TakeV8ConsumeTask(), while others with the same
// ScriptResource don't use ScriptCacheConsumer. It's fine even if a
// ClassicPendingScript is notified finished (with or without
// ScriptCacheConsumer), and executes a script for a ScriptResource while
// another ClassicPendingScript for the same ScriptResource with the same
// CachedMetadata is still waiting for ScriptCacheConsumer completion.
class CORE_EXPORT ScriptCacheConsumer final
    : public GarbageCollected<ScriptCacheConsumer> { … };

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_BINDINGS_CORE_V8_SCRIPT_CACHE_CONSUMER_H_