chromium/net/http/http_cache_writers.h

// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_HTTP_HTTP_CACHE_WRITERS_H_
#define NET_HTTP_HTTP_CACHE_WRITERS_H_

#include <map>
#include <memory>

#include "base/memory/raw_ptr.h"
#include "base/memory/weak_ptr.h"
#include "net/base/completion_once_callback.h"
#include "net/http/http_cache.h"
#include "net/http/http_response_info.h"

namespace net {

class HttpResponseInfo;
class IOBuffer;
class PartialData;

// If multiple HttpCache::Transactions are accessing the same cache entry
// simultaneously, their access to the data read from network is synchronized
// by HttpCache::Writers. This enables each of those transactions to drive
// reading the response body from the network ensuring a slow consumer does not
// starve other consumers of the same resource.
//
// Writers represents the set of all HttpCache::Transactions that are reading
// from the network using the same network transaction and writing to the same
// cache entry. It is owned by the ActiveEntry. The writers object must be
// deleted when HttpCache::WritersDoneWritingToEntry is called as it doesn't
// expect any of its ongoing IO transactions (e.g., network reads or cache
// writers) to complete after that point and won't know what to do with them.
class NET_EXPORT_PRIVATE HttpCache::Writers { … };

}  // namespace net

#endif  // NET_HTTP_HTTP_CACHE_WRITERS_H_