262 lines
8.2 KiB
C
262 lines
8.2 KiB
C
|
/**
|
||
|
|
* LibBoostAsio.h
|
||
|
|
*
|
||
|
|
* Implementation for the AMQP::TcpHandler that is optimized for boost::asio. You can
|
||
|
|
* use this class instead of a AMQP::TcpHandler class, just pass the boost asio service
|
||
|
|
* to the constructor and you're all set
|
||
|
|
*
|
||
|
|
* @author Gavin Smith <gavin.smith@coralbay.tv>
|
||
|
|
*/
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Include guard
|
||
|
|
*/
|
||
|
|
#pragma once
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Set up namespace
|
||
|
|
*/
|
||
|
|
namespace AMQP {
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Class definition
|
||
|
|
* @note Because of a limitation with boost::asio on Windows, this will only work on POSIX based systems - see https://github.com/chriskohlhoff/asio/issues/70
|
||
|
|
*/
|
||
|
|
class LibBoostAsioHandler : public virtual TcpHandler
|
||
|
|
{
|
||
|
|
private:
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Helper class that wraps a boost io_service socket monitor.
|
||
|
|
*/
|
||
|
|
class Watcher
|
||
|
|
{
|
||
|
|
private:
|
||
|
|
|
||
|
|
/**
|
||
|
|
* The boost asio io_service which is responsible for detecting events.
|
||
|
|
* @var class boost::asio::io_service&
|
||
|
|
*/
|
||
|
|
boost::asio::io_service & _ioservice;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* The boost tcp socket.
|
||
|
|
* @var class boost::asio::ip::tcp::socket
|
||
|
|
* @note https://stackoverflow.com/questions/38906711/destroying-boost-asio-socket-without-closing-native-handler
|
||
|
|
*/
|
||
|
|
boost::asio::posix::stream_descriptor _socket;
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* A boolean that indicates if the watcher is monitoring for read events.
|
||
|
|
* @var _read True if reads are being monitored else false.
|
||
|
|
*/
|
||
|
|
bool _read{false};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* A boolean that indicates if the watcher is monitoring for write events.
|
||
|
|
* @var _read True if writes are being monitored else false.
|
||
|
|
*/
|
||
|
|
bool _write{false};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Handler method that is called by boost's io_service when the socket pumps a read event.
|
||
|
|
* @param ec The status of the callback.
|
||
|
|
* @param connection The connection being watched.
|
||
|
|
* @param fd The file descriptor being watched.
|
||
|
|
* @note The handler will get called if a read is cancelled.
|
||
|
|
*/
|
||
|
|
void read_handler(boost::system::error_code ec, TcpConnection *connection, int fd)
|
||
|
|
{
|
||
|
|
if (!ec && _read)
|
||
|
|
{
|
||
|
|
connection->process(fd, AMQP::readable);
|
||
|
|
|
||
|
|
_socket.async_read_some(boost::asio::null_buffers(),
|
||
|
|
boost::bind(&Watcher::read_handler,
|
||
|
|
this,
|
||
|
|
boost::placeholders::_1,
|
||
|
|
connection,
|
||
|
|
fd));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Handler method that is called by boost's io_service when the socket pumps a write event.
|
||
|
|
* @param ec The status of the callback.
|
||
|
|
* @param connection The connection being watched.
|
||
|
|
* @param fd The file descriptor being watched.
|
||
|
|
* @note The handler will get called if a write is cancelled.
|
||
|
|
*/
|
||
|
|
void write_handler(boost::system::error_code ec, TcpConnection *connection, int fd)
|
||
|
|
{
|
||
|
|
if (!ec && _write)
|
||
|
|
{
|
||
|
|
connection->process(fd, AMQP::writable);
|
||
|
|
|
||
|
|
_socket.async_write_some(boost::asio::null_buffers(),
|
||
|
|
boost::bind(&Watcher::write_handler,
|
||
|
|
this,
|
||
|
|
boost::placeholders::_1,
|
||
|
|
connection,
|
||
|
|
fd));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
public:
|
||
|
|
/**
|
||
|
|
* Constructor
|
||
|
|
* @param io_service The boost io_service
|
||
|
|
* @param connection The connection being watched
|
||
|
|
* @param fd The filedescriptor being watched
|
||
|
|
* @param events The events that should be monitored
|
||
|
|
*/
|
||
|
|
Watcher(boost::asio::io_service &io_service, TcpConnection *connection, int fd, int events) :
|
||
|
|
_ioservice(io_service),
|
||
|
|
_socket(_ioservice)
|
||
|
|
{
|
||
|
|
_socket.assign(fd);
|
||
|
|
|
||
|
|
_socket.non_blocking(true);
|
||
|
|
|
||
|
|
// configure monitoring
|
||
|
|
this->events(connection,fd,events);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Watchers cannot be copied or moved
|
||
|
|
*
|
||
|
|
* @param that The object to not move or copy
|
||
|
|
*/
|
||
|
|
Watcher(Watcher &&that) = delete;
|
||
|
|
Watcher(const Watcher &that) = delete;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Destructor
|
||
|
|
*/
|
||
|
|
~Watcher()
|
||
|
|
{
|
||
|
|
_socket.release();
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Change the events for which the filedescriptor is monitored
|
||
|
|
* @param events
|
||
|
|
*/
|
||
|
|
void events(TcpConnection *connection, int fd, int events)
|
||
|
|
{
|
||
|
|
bool bRead(_read);
|
||
|
|
bool bWrite(_write);
|
||
|
|
|
||
|
|
// 1. Handle reads?
|
||
|
|
_read = ((events & AMQP::readable) != 0);
|
||
|
|
|
||
|
|
if (!bRead && _read)
|
||
|
|
{
|
||
|
|
_socket.async_read_some(boost::asio::null_buffers(),
|
||
|
|
boost::bind(&Watcher::read_handler,
|
||
|
|
this,
|
||
|
|
boost::placeholders::_1,
|
||
|
|
connection,
|
||
|
|
fd));
|
||
|
|
}
|
||
|
|
|
||
|
|
// 2. Handle writes?
|
||
|
|
_write = ((events & AMQP::writable) != 0);
|
||
|
|
|
||
|
|
if (!bWrite && _write)
|
||
|
|
{
|
||
|
|
_socket.async_write_some(boost::asio::null_buffers(),
|
||
|
|
boost::bind(&Watcher::write_handler,
|
||
|
|
this,
|
||
|
|
boost::placeholders::_1,
|
||
|
|
connection,
|
||
|
|
fd));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* The boost asio io_service.
|
||
|
|
* @var class boost::asio::io_service&
|
||
|
|
*/
|
||
|
|
boost::asio::io_service & _ioservice;
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* All I/O watchers that are active, indexed by their filedescriptor
|
||
|
|
* @var std::map<int,Watcher>
|
||
|
|
*/
|
||
|
|
std::map<int, std::unique_ptr<Watcher> > _watchers;
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Method that is called by AMQP-CPP to register a filedescriptor for readability or writability
|
||
|
|
* @param connection The TCP connection object that is reporting
|
||
|
|
* @param fd The filedescriptor to be monitored
|
||
|
|
* @param flags Should the object be monitored for readability or writability?
|
||
|
|
*/
|
||
|
|
void monitor(TcpConnection *connection, int fd, int flags) override
|
||
|
|
{
|
||
|
|
// do we already have this filedescriptor
|
||
|
|
auto iter = _watchers.find(fd);
|
||
|
|
|
||
|
|
// was it found?
|
||
|
|
if (iter == _watchers.end())
|
||
|
|
{
|
||
|
|
// we did not yet have this watcher - but that is ok if no filedescriptor was registered
|
||
|
|
if (flags == 0){ return; }
|
||
|
|
|
||
|
|
// construct a new pair (watcher/timer), and put it in the map
|
||
|
|
_watchers[fd] = std::make_unique<Watcher>(_ioservice, connection, fd, flags);
|
||
|
|
}
|
||
|
|
else if (flags == 0)
|
||
|
|
{
|
||
|
|
// the watcher does already exist, but we no longer have to watch this watcher
|
||
|
|
_watchers.erase(iter);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// Change the events on which to act.
|
||
|
|
iter->second->events(connection,fd,flags);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
public:
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Handler cannot be default constructed.
|
||
|
|
*
|
||
|
|
* @param that The object to not move or copy
|
||
|
|
*/
|
||
|
|
LibBoostAsioHandler() = delete;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Constructor
|
||
|
|
* @param loop The boost io_service to wrap
|
||
|
|
*/
|
||
|
|
explicit LibBoostAsioHandler(boost::asio::io_service &io_service) : _ioservice(io_service) {}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Handler cannot be copied or moved
|
||
|
|
*
|
||
|
|
* @param that The object to not move or copy
|
||
|
|
*/
|
||
|
|
LibBoostAsioHandler(LibBoostAsioHandler &&that) = delete;
|
||
|
|
LibBoostAsioHandler(const LibBoostAsioHandler &that) = delete;
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Destructor
|
||
|
|
*/
|
||
|
|
~LibBoostAsioHandler() override = default;
|
||
|
|
};
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* End of namespace
|
||
|
|
*/
|
||
|
|
}
|
||
|
|
|