mirror of
https://github.com/klzgrad/naiveproxy.git
synced 2024-11-24 22:36:09 +03:00
93 lines
3.5 KiB
C++
93 lines
3.5 KiB
C++
// Copyright 2016 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 NET_SPDY_CHROMIUM_HTTP2_PRIORITY_DEPENDENCIES_H_
|
|
#define NET_SPDY_CHROMIUM_HTTP2_PRIORITY_DEPENDENCIES_H_
|
|
|
|
#include <list>
|
|
#include <map>
|
|
#include <utility>
|
|
#include <vector>
|
|
|
|
#include "net/base/net_export.h"
|
|
#include "net/spdy/core/spdy_protocol.h"
|
|
|
|
namespace net {
|
|
|
|
// A helper class encapsulating the state and logic to set dependencies of
|
|
// HTTP2 streams based on their SpdyPriority and the ordering
|
|
// of creation and deletion of the streams.
|
|
class NET_EXPORT_PRIVATE Http2PriorityDependencies {
|
|
public:
|
|
Http2PriorityDependencies();
|
|
~Http2PriorityDependencies();
|
|
|
|
// Called when a stream is created. This is used for both client-initiated
|
|
// and server-initiated (pushed) streams.
|
|
// On return, |*dependent_stream_id| is set to the stream id that
|
|
// this stream should be made dependent on, and |*exclusive| set to
|
|
// whether that dependency should be exclusive.
|
|
void OnStreamCreation(SpdyStreamId id,
|
|
SpdyPriority priority,
|
|
SpdyStreamId* dependent_stream_id,
|
|
bool* exclusive);
|
|
|
|
// Called when a stream is destroyed.
|
|
void OnStreamDestruction(SpdyStreamId id);
|
|
|
|
struct DependencyUpdate {
|
|
SpdyStreamId id;
|
|
SpdyStreamId dependent_stream_id;
|
|
bool exclusive;
|
|
};
|
|
|
|
// Called when a stream's priority has changed. Returns a list of
|
|
// dependency updates that should be sent to the server to describe
|
|
// the requested priority change. The updates should be sent in the
|
|
// given order.
|
|
std::vector<DependencyUpdate> OnStreamUpdate(SpdyStreamId id,
|
|
SpdyPriority new_priority);
|
|
|
|
// Returns the estimate of dynamically allocated memory in bytes.
|
|
size_t EstimateMemoryUsage() const;
|
|
|
|
private:
|
|
// The requirements for the internal data structure for this class are:
|
|
// a) Constant time insertion of entries at the end of the list,
|
|
// b) Fast removal of any entry based on its id.
|
|
// c) Constant time lookup of the entry at the end of the list.
|
|
// std::list would satisfy (a) & (c), but some form of map is
|
|
// needed for (b). The priority must be included in the map
|
|
// entries so that deletion can determine which list in id_priority_lists_
|
|
// to erase from.
|
|
using IdList = std::list<std::pair<SpdyStreamId, SpdyPriority>>;
|
|
using EntryMap = std::map<SpdyStreamId, IdList::iterator>;
|
|
|
|
IdList id_priority_lists_[kV3LowestPriority + 1];
|
|
|
|
// Tracks the location of an id anywhere in the above vector of lists.
|
|
// Iterators to list elements remain valid until those particular elements
|
|
// are erased.
|
|
EntryMap entry_by_stream_id_;
|
|
|
|
// Finds the lowest-priority stream that has a priority >= |priority|.
|
|
// Returns false if there are no such streams.
|
|
// Otherwise, returns true and sets |*bound|.
|
|
bool PriorityLowerBound(SpdyPriority priority, IdList::iterator* bound);
|
|
|
|
// Finds the stream just above |id| in the total order.
|
|
// Returns false if there are no streams with a higher priority.
|
|
// Otherwise, returns true and sets |*parent|.
|
|
bool ParentOfStream(SpdyStreamId id, IdList::iterator* parent);
|
|
|
|
// Finds the stream just below |id| in the total order.
|
|
// Returns false if there are no streams with a lower priority.
|
|
// Otherwise, returns true and sets |*child|.
|
|
bool ChildOfStream(SpdyStreamId id, IdList::iterator* child);
|
|
};
|
|
|
|
} // namespace net
|
|
|
|
#endif // NET_SPDY_CHROMIUM_HTTP2_PRIORITY_DEPENDENCIES_H_
|