/* Event pipe for GDB, the GNU debugger.
Copyright (C) 2021-2024 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <
http://www.gnu.org/licenses/>. */
#ifndef GDBSUPPORT_EVENT_PIPE_H
#define GDBSUPPORT_EVENT_PIPE_H
/* An event pipe used as a waitable file in the event loop in place of
some other event associated with a signal. The handler for the
signal marks the event pipe to force a wakeup in the event loop.
This uses the well-known self-pipe trick. */
class event_pipe
{
public:
event_pipe() = default;
~event_pipe();
DISABLE_COPY_AND_ASSIGN (event_pipe);
/* Create a new pipe. */
bool open_pipe ();
/* Close the pipe. */
void close_pipe ();
/* True if the event pipe has been opened. */
bool is_open () const
{ return m_fds[0] != -1; }
/* The file descriptor of the waitable file to use in the event
loop. */
int event_fd () const
{ return m_fds[0]; }
/* Flush the event pipe. */
void flush ();
/* Put something in the pipe, so the event loop wakes up. */
void mark ();
private:
int m_fds[2] = { -1, -1 };
};
#endif /* GDBSUPPORT_EVENT_PIPE_H */
