tmux/job.c
Nicholas Marriott 6bca92db4d 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.
2009-10-10 15:03:01 +00:00

188 lines
3.7 KiB
C

/* $OpenBSD$ */
/*
* Copyright (c) 2009 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 <fcntl.h>
#include <paths.h>
#include <string.h>
#include <unistd.h>
#include "tmux.h"
/*
* Job scheduling. Run queued commands in the background and record their
* output.
*/
RB_GENERATE(jobs, job, entry, job_cmp);
int
job_cmp(struct job *job1, struct job *job2)
{
return (strcmp(job1->cmd, job2->cmd));
}
/* Initialise job tree. */
void
job_tree_init(struct jobs *jobs)
{
RB_INIT(jobs);
}
/* Count the number of jobs in a tree. */
u_int
job_tree_size(struct jobs *jobs)
{
struct job *job;
u_int n;
n = 0;
RB_FOREACH(job, jobs, jobs)
n++;
return (n);
}
/* Destroy a job tree. */
void
job_tree_free(struct jobs *jobs)
{
struct job *job;
while (!RB_EMPTY(jobs)) {
job = RB_ROOT(jobs);
RB_REMOVE(jobs, jobs, job);
job_free(job);
}
}
/* Find a job and return it. */
struct job *
job_get(struct jobs *jobs, const char *cmd)
{
struct job job;
job.cmd = (char *) cmd;
return (RB_FIND(jobs, jobs, &job));
}
/* Add a job. */
struct job *
job_add(struct jobs *jobs, struct client *c, const char *cmd,
void (*callbackfn)(struct job *), void (*freefn)(void *), void *data)
{
struct job *job;
job = xmalloc(sizeof *job);
job->cmd = xstrdup(cmd);
job->client = c;
job->fd = -1;
job->out = buffer_create(BUFSIZ);
job->callbackfn = callbackfn;
job->freefn = freefn;
job->data = data;
RB_INSERT(jobs, jobs, job);
return (job);
}
/* Kill and free an individual job. */
void
job_free(struct job *job)
{
job_kill(job);
xfree(job->cmd);
if (job->fd != -1)
close(job->fd);
if (job->out != NULL)
buffer_destroy(job->out);
xfree(job);
}
/* Start a job running, if it isn't already. */
int
job_run(struct job *job)
{
int nullfd, out[2], mode;
if (job->fd != -1)
return (0);
if (pipe(out) != 0)
return (-1);
switch (job->pid = fork()) {
case -1:
return (-1);
case 0: /* child */
sigreset();
/* XXX environ? */
nullfd = open(_PATH_DEVNULL, O_RDONLY, 0);
if (nullfd < 0)
fatal("open failed");
if (dup2(nullfd, STDIN_FILENO) == -1)
fatal("dup2 failed");
if (dup2(nullfd, STDERR_FILENO) == -1)
fatal("dup2 failed");
if (nullfd != STDIN_FILENO && nullfd != STDERR_FILENO)
close(nullfd);
close(out[1]);
if (dup2(out[0], STDOUT_FILENO) == -1)
fatal("dup2 failed");
if (out[0] != STDOUT_FILENO)
close(out[0]);
execl(_PATH_BSHELL, "sh", "-c", job->cmd, (char *) NULL);
fatal("execl failed");
default: /* parent */
close(out[0]);
job->fd = out[1];
if ((mode = fcntl(job->fd, F_GETFL)) == -1)
fatal("fcntl failed");
if (fcntl(job->fd, F_SETFL, mode|O_NONBLOCK) == -1)
fatal("fcntl failed");
if (fcntl(job->fd, F_SETFD, FD_CLOEXEC) == -1)
fatal("fcntl failed");
if (BUFFER_USED(job->out) != 0)
buffer_remove(job->out, BUFFER_USED(job->out));
return (0);
}
}
/* Kill a job. */
void
job_kill(struct job *job)
{
if (job->pid == -1)
return;
kill(job->pid, SIGTERM);
job->pid = -1;
}