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/******************************************************************************
* ____ _ _____ *
* / ___| / \ | ___| C++ *
* | | / _ \ | |_ Actor *
* | |___ / ___ \| _| Framework *
* \____/_/ \_|_| *
* *
* Copyright 2011-2018 Dominik Charousset *
* *
* Distributed under the terms and conditions of the BSD 3-Clause License or *
* (at your option) under the terms and conditions of the Boost Software *
* License 1.0. See accompanying files LICENSE and LICENSE_ALTERNATIVE. *
* *
* If you did not receive a copy of the license files, see *
* http://opensource.org/licenses/BSD-3-Clause and *
* http://www.boost.org/LICENSE_1_0.txt. *
******************************************************************************/
#pragma once
#include "caf/io/fwd.hpp"
#include "caf/io/network/native_socket.hpp"
#include "caf/io/network/operation.hpp"
#include "caf/io/receive_policy.hpp"
namespace caf {
namespace io {
namespace network {
/// A socket I/O event handler.
class event_handler {
public:
/// Stores various status flags and user-defined config parameters.
struct state {
/// Stores whether the socket is currently registered for reading.
bool reading : 1;
/// Stores whether the socket is currently registered for writing.
bool writing : 1;
/// Stores whether the parent actor demanded write receipts.
bool ack_writes : 1;
/// Stores whether graceful_shutdown() was called.
bool shutting_down : 1;
/// Stores what receive policy is currently active.
unsigned rd_flag : 2;
};
event_handler(default_multiplexer& dm, native_socket sockfd);
virtual ~event_handler();
/// Returns true once the requested operation is done, i.e.,
/// to signalize the multiplexer to remove this handler.
/// The handler remains in the event loop as long as it returns false.
virtual void handle_event(operation op) = 0;
/// Callback to signalize that this handler has been removed
/// from the event loop for operations of type `op`.
virtual void removed_from_loop(operation op) = 0;
/// Shuts down communication on the managed socket, eventually removing
/// this event handler from the I/O loop.
virtual void graceful_shutdown() = 0;
/// Returns the native socket handle for this handler.
native_socket fd() const {
return fd_;
}
/// Returns the `multiplexer` this acceptor belongs to.
default_multiplexer& backend() {
return backend_;
}
/// Returns the bit field storing the subscribed events.
int eventbf() const {
return eventbf_;
}
/// Sets the bit field storing the subscribed events.
void eventbf(int value) {
eventbf_ = value;
}
/// Checks whether `close_read_channel` has been called.
bool read_channel_closed() const {
return !state_.reading;
}
/// Removes the file descriptor from the event loop of the parent.
void passivate();
/// Returns whether this event handlers signals successful writes to its
/// parent actor.
bool ack_writes() {
return state_.ack_writes;
}
/// Sets whether this event handlers signals successful writes to its parent
/// actor.
void ack_writes(bool x) {
state_.ack_writes = x;
}
protected:
/// Adds the file descriptor to the event loop of the parent.
void activate();
/// Sets flags for asynchronous event handling on the socket handle.
void set_fd_flags();
native_socket fd_;
state state_;
int eventbf_;
default_multiplexer& backend_;
};
} // namespace network
} // namespace io
} // namespace caf
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