nghttp2/src/shrpx_connect_blocker.h

87 lines
2.6 KiB
C++

/*
* nghttp2 - HTTP/2 C Library
*
* Copyright (c) 2014 Tatsuhiro Tsujikawa
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef SHRPX_CONNECT_BLOCKER_H
#define SHRPX_CONNECT_BLOCKER_H
#include "shrpx.h"
#include <random>
#include <functional>
#include <ev.h>
namespace shrpx {
class ConnectBlocker {
public:
ConnectBlocker(std::mt19937 &gen, struct ev_loop *loop,
std::function<void()> block_func,
std::function<void()> unblock_func);
~ConnectBlocker();
// Returns true if making connection is not allowed.
bool blocked() const;
// Call this function if connect operation succeeded. This will
// reset sleep_ to minimum value.
void on_success();
// Call this function if connect operations failed. This will start
// timer and blocks connection establishment with exponential
// backoff.
void on_failure();
size_t get_fail_count() const;
// Peer is now considered offline. This effectively means that the
// connection is blocked until online() is called.
void offline();
// Peer is now considered online
void online();
// Returns true if peer is considered offline.
bool in_offline() const;
void call_block_func();
void call_unblock_func();
private:
std::mt19937 &gen_;
// Called when blocking is started
std::function<void()> block_func_;
// Called when unblocked
std::function<void()> unblock_func_;
ev_timer timer_;
struct ev_loop *loop_;
// The number of consecutive connection failure. Reset to 0 on
// success.
size_t fail_count_;
// true if peer is considered offline.
bool offline_;
};
} // namespace
#endif // SHRPX_CONNECT_BLOCKER_H