poco/Net/include/Poco/Net/PollSet.h
2022-07-05 20:49:46 +02:00

125 lines
3.0 KiB
C++

//
// PollSet.h
//
// Library: Net
// Package: Sockets
// Module: PollSet
//
// Definition of the PollSet class.
//
// Copyright (c) 2016, Applied Informatics Software Engineering GmbH.
// All rights reserved.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Net_PollSet_INCLUDED
#define Net_PollSet_INCLUDED
#include "Poco/Net/Socket.h"
#include <map>
namespace Poco {
namespace Net {
class PollSetImpl;
class Net_API PollSet
/// A set of sockets that can be efficiently polled as a whole.
///
/// If supported, PollSet is implemented using epoll (Linux) or
/// poll (BSD) APIs. A fallback implementation using select()
/// is also provided.
{
public:
enum Mode
{
POLL_READ = Socket::SELECT_READ,
POLL_WRITE = Socket::SELECT_WRITE,
POLL_ERROR = Socket::SELECT_ERROR
};
using SocketModeMap = std::map<Poco::Net::Socket, int>;
PollSet();
/// Creates an empty PollSet.
~PollSet();
/// Destroys the PollSet.
void add(const Poco::Net::Socket& socket, int mode);
/// Adds the given socket to the set, for polling with
/// the given mode, which can be an OR'd combination of
/// POLL_READ, POLL_WRITE and POLL_ERROR.
/// Subsequent socket additions to the PollSet are mode-cumulative,
/// so the following code:
///
/// StreamSocket ss;
/// PollSet ps;
/// ps.add(ss, PollSet::POLL_READ);
/// ps.add(ss, PollSet::POLL_WRITE);
///
/// shall result in the socket being monitored for read and write,
/// equivalent to this:
///
/// ps.update(ss, PollSet::POLL_READ | PollSet::POLL_WRITE);
void remove(const Poco::Net::Socket& socket);
/// Removes the given socket from the set.
void update(const Poco::Net::Socket& socket, int mode);
/// Updates the mode of the given socket. If socket does
/// not exist in the PollSet, it is silently added. For
/// an existing socket, any prior mode is overwritten.
/// Updating socket is non-mode-cumulative.
///
/// The following code:
///
/// StreamSocket ss;
/// PollSet ps;
/// ps.update(ss, PollSet::POLL_READ);
/// ps.update(ss, PollSet::POLL_WRITE);
///
/// shall result in the socket being monitored for write only.
bool has(const Socket& socket) const;
/// Returns true if socket is registered for polling.
bool empty() const;
/// Returns true if no socket is registered for polling.
void clear();
/// Removes all sockets from the PollSet.
SocketModeMap poll(const Poco::Timespan& timeout);
/// Waits until the state of at least one of the PollSet's sockets
/// changes accordingly to its mode, or the timeout expires.
/// Returns a PollMap containing the sockets that have had
/// their state changed.
int count() const;
/// Returns the number of sockets monitored.
void wakeUp();
/// Wakes up a waiting PollSet.
/// Any errors that occur during this call are ignored.
/// On platforms/implementations where this functionality
/// is not available, it does nothing.
private:
PollSetImpl* _pImpl;
PollSet(const PollSet&);
PollSet& operator = (const PollSet&);
};
} } // namespace Poco::Net
#endif // Net_PollSet_INCLUDED