mc/lib/tty/tty-internal.c
Andrew Borodin 37ffc02422 Ticket #117: refactoring of SIGWINCH hangling.
Use pipe to collect consecutive raised SIGWINCH events.
Then handle multiple events at a time treating them
as a single one.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
2019-09-01 19:22:21 +03:00

105 lines
3.4 KiB
C

/*
Internal stuff of the terminal controlling library.
Copyright (C) 2019
Free Software Foundation, Inc.
Written by:
Andrew Borodin <aborodin@vmail.ru>, 2019.
This file is part of the Midnight Commander.
The Midnight Commander 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.
The Midnight Commander 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/>.
*/
/** \file
* \brief Source: internal stuff of the terminal controlling library.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include "lib/global.h"
#include "tty-internal.h"
/*** global variables ****************************************************************************/
/* pipe to handle SIGWINCH */
int sigwinch_pipe[2];
/*** file scope macro definitions ****************************************************************/
/*** global variables ****************************************************************************/
/*** file scope type declarations ****************************************************************/
/*** file scope variables ************************************************************************/
/* --------------------------------------------------------------------------------------------- */
/*** file scope functions ************************************************************************/
/* --------------------------------------------------------------------------------------------- */
/* --------------------------------------------------------------------------------------------- */
/*** public functions ****************************************************************************/
/* --------------------------------------------------------------------------------------------- */
void
tty_create_winch_pipe (void)
{
int fd_flags;
if (pipe (sigwinch_pipe) == -1)
{
perror (_("Cannot create pipe for SIGWINCH"));
exit (EXIT_FAILURE);
}
/* If we read from an empty pipe, then read(2) will block until data is available.
* If we write to a full pipe, then write(2) blocks until sufficient data has been read
* from the pipe to allow the write to complete..
* Therefore, use nonblocking I/O.
*/
fd_flags = fcntl (sigwinch_pipe[0], F_GETFL, NULL);
if (fd_flags != -1)
{
fd_flags |= O_NONBLOCK | O_CLOEXEC;
fd_flags = fcntl (sigwinch_pipe[0], F_SETFL, fd_flags);
}
if (fd_flags == -1)
{
perror (_("Cannot configure write end of SIGWINCH pipe"));
exit (EXIT_FAILURE);
}
fd_flags = fcntl (sigwinch_pipe[1], F_GETFL, NULL);
if (fd_flags != -1)
{
fd_flags |= O_NONBLOCK | O_CLOEXEC;
fd_flags = fcntl (sigwinch_pipe[1], F_SETFL, fd_flags);
}
if (fd_flags == -1)
{
perror (_("Cannot configure read end of SIGWINCH pipe"));
exit (EXIT_FAILURE);
}
}
/* --------------------------------------------------------------------------------------------- */