tmux/buffer-poll.c
Tiago Cunha bc236109fd Sync OpenBSD patchset 374:
Rather than running status-left, status-right and window title #() with popen
immediately every redraw, queue them up and run them in the background,
starting each once every status-interval. The actual status line uses the
output from the last run.

This brings several advantages:

- tmux itself may be called from inside #() without causing the server to hang;
- likewise, sleep or similar doesn't cause the server to block;
- commands aren't run excessively often when redrawing;
- commands shared by status-left and status-right, or used multiple times, will
  only be run once.

run-shell and if-shell still use system()/popen() but will be changed over to
use this too later.
2009-10-11 23:55:26 +00:00

56 lines
1.7 KiB
C

/* $Id: buffer-poll.c,v 1.17 2009-10-11 23:55:26 tcunha Exp $ */
/*
* Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
* IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/types.h>
#include <errno.h>
#include <unistd.h>
#include "tmux.h"
/* Fill buffers from socket based on poll results. */
int
buffer_poll(struct pollfd *pfd, struct buffer *in, struct buffer *out)
{
ssize_t n;
if (pfd->revents & (POLLERR|POLLNVAL))
return (-1);
if (in != NULL && pfd->revents & POLLIN) {
buffer_ensure(in, BUFSIZ);
n = read(pfd->fd, BUFFER_IN(in), BUFFER_FREE(in));
if (n == 0)
return (-1);
if (n == -1) {
if (errno != EINTR && errno != EAGAIN)
return (-1);
} else
buffer_add(in, n);
} else if (pfd->revents & POLLHUP)
return (-1);
if (out != NULL && BUFFER_USED(out) > 0 && pfd->revents & POLLOUT) {
n = write(pfd->fd, BUFFER_OUT(out), BUFFER_USED(out));
if (n == -1) {
if (errno != EINTR && errno != EAGAIN)
return (-1);
} else
buffer_remove(out, n);
}
return (0);
}