xref: /netbsd-src/external/bsd/tmux/dist/job.c (revision 890b6d91a44b7fcb2dfbcbc1e93463086e462d2d)
1 /* $OpenBSD$ */
2 
3 /*
4  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 #include <sys/ioctl.h>
21 #include <sys/socket.h>
22 #include <sys/wait.h>
23 
24 #include <fcntl.h>
25 #include <signal.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <unistd.h>
29 
30 #include "tmux.h"
31 
32 /*
33  * Job scheduling. Run queued commands in the background and record their
34  * output.
35  */
36 
37 static void	job_read_callback(struct bufferevent *, void *);
38 static void	job_write_callback(struct bufferevent *, void *);
39 static void	job_error_callback(struct bufferevent *, short, void *);
40 
41 /* A single job. */
42 struct job {
43 	enum {
44 		JOB_RUNNING,
45 		JOB_DEAD,
46 		JOB_CLOSED
47 	} state;
48 
49 	int			 flags;
50 
51 	char			*cmd;
52 	pid_t			 pid;
53 	char		         tty[TTY_NAME_MAX];
54 	int			 status;
55 
56 	int			 fd;
57 	struct bufferevent	*event;
58 
59 	job_update_cb		 updatecb;
60 	job_complete_cb		 completecb;
61 	job_free_cb		 freecb;
62 	void			*data;
63 
64 	LIST_ENTRY(job)		 entry;
65 };
66 
67 /* All jobs list. */
68 static LIST_HEAD(joblist, job) all_jobs = LIST_HEAD_INITIALIZER(all_jobs);
69 
70 /* Start a job running. */
71 struct job *
72 job_run(const char *cmd, int argc, char **argv, struct environ *e,
73     struct session *s, const char *cwd, job_update_cb updatecb,
74     job_complete_cb completecb, job_free_cb freecb, void *data, int flags,
75     int sx, int sy)
76 {
77 	struct job	 *job;
78 	struct environ	 *env;
79 	pid_t		  pid;
80 	int		  nullfd, out[2], master;
81 	const char	 *home, *shell;
82 	sigset_t	  set, oldset;
83 	struct winsize	  ws;
84 	char		**argvp, tty[TTY_NAME_MAX], *argv0;
85 	struct options	 *oo;
86 
87 	/*
88 	 * Do not set TERM during .tmux.conf (second argument here), it is nice
89 	 * to be able to use if-shell to decide on default-terminal based on
90 	 * outside TERM.
91 	 */
92 	env = environ_for_session(s, !cfg_finished);
93 	if (e != NULL)
94 		environ_copy(e, env);
95 
96 	if (~flags & JOB_DEFAULTSHELL)
97 		shell = _PATH_BSHELL;
98 	else {
99 		if (s != NULL)
100 			oo = s->options;
101 		else
102 			oo = global_s_options;
103 		shell = options_get_string(oo, "default-shell");
104 		if (!checkshell(shell))
105 			shell = _PATH_BSHELL;
106 	}
107 	argv0 = shell_argv0(shell, 0);
108 
109 	sigfillset(&set);
110 	sigprocmask(SIG_BLOCK, &set, &oldset);
111 
112 	if (flags & JOB_PTY) {
113 		memset(&ws, 0, sizeof ws);
114 		ws.ws_col = sx;
115 		ws.ws_row = sy;
116 		pid = fdforkpty(ptm_fd, &master, tty, NULL, &ws);
117 	} else {
118 		if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, out) != 0)
119 			goto fail;
120 		pid = fork();
121 	}
122 	if (cmd == NULL) {
123 		cmd_log_argv(argc, argv, "%s:", __func__);
124 		log_debug("%s: cwd=%s, shell=%s", __func__,
125 		    cwd == NULL ? "" : cwd, shell);
126 	} else {
127 		log_debug("%s: cmd=%s, cwd=%s, shell=%s", __func__, cmd,
128 		    cwd == NULL ? "" : cwd, shell);
129 	}
130 
131 	switch (pid) {
132 	case -1:
133 		if (~flags & JOB_PTY) {
134 			close(out[0]);
135 			close(out[1]);
136 		}
137 		goto fail;
138 	case 0:
139 		proc_clear_signals(server_proc, 1);
140 		sigprocmask(SIG_SETMASK, &oldset, NULL);
141 
142 		if ((cwd == NULL || chdir(cwd) != 0) &&
143 		    ((home = find_home()) == NULL || chdir(home) != 0) &&
144 		    chdir("/") != 0)
145 			fatal("chdir failed");
146 
147 		environ_push(env);
148 		environ_free(env);
149 
150 		if (~flags & JOB_PTY) {
151 			if (dup2(out[1], STDIN_FILENO) == -1)
152 				fatal("dup2 failed");
153 			if (dup2(out[1], STDOUT_FILENO) == -1)
154 				fatal("dup2 failed");
155 			if (out[1] != STDIN_FILENO && out[1] != STDOUT_FILENO)
156 				close(out[1]);
157 			close(out[0]);
158 
159 			nullfd = open(_PATH_DEVNULL, O_RDWR);
160 			if (nullfd == -1)
161 				fatal("open failed");
162 			if (dup2(nullfd, STDERR_FILENO) == -1)
163 				fatal("dup2 failed");
164 			if (nullfd != STDERR_FILENO)
165 				close(nullfd);
166 		}
167 		closefrom(STDERR_FILENO + 1);
168 
169 		if (cmd != NULL) {
170 			setenv("SHELL", shell, 1);
171 			execl(shell, argv0, "-c", cmd, (char *)NULL);
172 			fatal("execl failed");
173 		} else {
174 			argvp = cmd_copy_argv(argc, argv);
175 			execvp(argvp[0], argvp);
176 			fatal("execvp failed");
177 		}
178 	}
179 
180 	sigprocmask(SIG_SETMASK, &oldset, NULL);
181 	environ_free(env);
182 	free(argv0);
183 
184 	job = xmalloc(sizeof *job);
185 	job->state = JOB_RUNNING;
186 	job->flags = flags;
187 
188 	if (cmd != NULL)
189 		job->cmd = xstrdup(cmd);
190 	else
191 		job->cmd = cmd_stringify_argv(argc, argv);
192 	job->pid = pid;
193 	strlcpy(job->tty, tty, sizeof job->tty);
194 	job->status = 0;
195 
196 	LIST_INSERT_HEAD(&all_jobs, job, entry);
197 
198 	job->updatecb = updatecb;
199 	job->completecb = completecb;
200 	job->freecb = freecb;
201 	job->data = data;
202 
203 	if (~flags & JOB_PTY) {
204 		close(out[1]);
205 		job->fd = out[0];
206 	} else
207 		job->fd = master;
208 	setblocking(job->fd, 0);
209 
210 	job->event = bufferevent_new(job->fd, job_read_callback,
211 	    job_write_callback, job_error_callback, job);
212 	if (job->event == NULL)
213 		fatalx("out of memory");
214 	bufferevent_enable(job->event, EV_READ|EV_WRITE);
215 
216 	log_debug("run job %p: %s, pid %ld", job, job->cmd, (long)job->pid);
217 	return (job);
218 
219 fail:
220 	sigprocmask(SIG_SETMASK, &oldset, NULL);
221 	environ_free(env);
222 	free(argv0);
223 	return (NULL);
224 }
225 
226 /* Take job's file descriptor and free the job. */
227 int
228 job_transfer(struct job *job, pid_t *pid, char *tty, size_t ttylen)
229 {
230 	int	fd = job->fd;
231 
232 	log_debug("transfer job %p: %s", job, job->cmd);
233 
234 	if (pid != NULL)
235 		*pid = job->pid;
236 	if (tty != NULL)
237 		strlcpy(tty, job->tty, ttylen);
238 
239 	LIST_REMOVE(job, entry);
240 	free(job->cmd);
241 
242 	if (job->freecb != NULL && job->data != NULL)
243 		job->freecb(job->data);
244 
245 	if (job->event != NULL)
246 		bufferevent_free(job->event);
247 
248 	free(job);
249 	return (fd);
250 }
251 
252 /* Kill and free an individual job. */
253 void
254 job_free(struct job *job)
255 {
256 	log_debug("free job %p: %s", job, job->cmd);
257 
258 	LIST_REMOVE(job, entry);
259 	free(job->cmd);
260 
261 	if (job->freecb != NULL && job->data != NULL)
262 		job->freecb(job->data);
263 
264 	if (job->pid != -1)
265 		kill(job->pid, SIGTERM);
266 	if (job->event != NULL)
267 		bufferevent_free(job->event);
268 	if (job->fd != -1)
269 		close(job->fd);
270 
271 	free(job);
272 }
273 
274 /* Resize job. */
275 void
276 job_resize(struct job *job, u_int sx, u_int sy)
277 {
278 	struct winsize	 ws;
279 
280 	if (job->fd == -1 || (~job->flags & JOB_PTY))
281 		return;
282 
283 	log_debug("resize job %p: %ux%u", job, sx, sy);
284 
285 	memset(&ws, 0, sizeof ws);
286 	ws.ws_col = sx;
287 	ws.ws_row = sy;
288 	if (ioctl(job->fd, TIOCSWINSZ, &ws) == -1)
289 		fatal("ioctl failed");
290 }
291 
292 /* Job buffer read callback. */
293 static void
294 job_read_callback(__unused struct bufferevent *bufev, void *data)
295 {
296 	struct job	*job = data;
297 
298 	if (job->updatecb != NULL)
299 		job->updatecb(job);
300 }
301 
302 /*
303  * Job buffer write callback. Fired when the buffer falls below watermark
304  * (default is empty). If all the data has been written, disable the write
305  * event.
306  */
307 static void
308 job_write_callback(__unused struct bufferevent *bufev, void *data)
309 {
310 	struct job	*job = data;
311 	size_t		 len = EVBUFFER_LENGTH(EVBUFFER_OUTPUT(job->event));
312 
313 	log_debug("job write %p: %s, pid %ld, output left %zu", job, job->cmd,
314 	    (long) job->pid, len);
315 
316 	if (len == 0 && (~job->flags & JOB_KEEPWRITE)) {
317 		shutdown(job->fd, SHUT_WR);
318 		bufferevent_disable(job->event, EV_WRITE);
319 	}
320 }
321 
322 /* Job buffer error callback. */
323 static void
324 job_error_callback(__unused struct bufferevent *bufev, __unused short events,
325     void *data)
326 {
327 	struct job	*job = data;
328 
329 	log_debug("job error %p: %s, pid %ld", job, job->cmd, (long) job->pid);
330 
331 	if (job->state == JOB_DEAD) {
332 		if (job->completecb != NULL)
333 			job->completecb(job);
334 		job_free(job);
335 	} else {
336 		bufferevent_disable(job->event, EV_READ);
337 		job->state = JOB_CLOSED;
338 	}
339 }
340 
341 /* Job died (waitpid() returned its pid). */
342 void
343 job_check_died(pid_t pid, int status)
344 {
345 	struct job	*job;
346 
347 	LIST_FOREACH(job, &all_jobs, entry) {
348 		if (pid == job->pid)
349 			break;
350 	}
351 	if (job == NULL)
352 		return;
353 	if (WIFSTOPPED(status)) {
354 		if (WSTOPSIG(status) == SIGTTIN || WSTOPSIG(status) == SIGTTOU)
355 			return;
356 		killpg(job->pid, SIGCONT);
357 		return;
358 	}
359 	log_debug("job died %p: %s, pid %ld", job, job->cmd, (long) job->pid);
360 
361 	job->status = status;
362 
363 	if (job->state == JOB_CLOSED) {
364 		if (job->completecb != NULL)
365 			job->completecb(job);
366 		job_free(job);
367 	} else {
368 		job->pid = -1;
369 		job->state = JOB_DEAD;
370 	}
371 }
372 
373 /* Get job status. */
374 int
375 job_get_status(struct job *job)
376 {
377 	return (job->status);
378 }
379 
380 /* Get job data. */
381 void *
382 job_get_data(struct job *job)
383 {
384 	return (job->data);
385 }
386 
387 /* Get job event. */
388 struct bufferevent *
389 job_get_event(struct job *job)
390 {
391 	return (job->event);
392 }
393 
394 /* Kill all jobs. */
395 void
396 job_kill_all(void)
397 {
398 	struct job	*job;
399 
400 	LIST_FOREACH(job, &all_jobs, entry) {
401 		if (job->pid != -1)
402 			kill(job->pid, SIGTERM);
403 	}
404 }
405 
406 /* Are any jobs still running? */
407 int
408 job_still_running(void)
409 {
410 	struct job	*job;
411 
412 	LIST_FOREACH(job, &all_jobs, entry) {
413 		if ((~job->flags & JOB_NOWAIT) && job->state == JOB_RUNNING)
414 			return (1);
415 	}
416 	return (0);
417 }
418 
419 /* Print job summary. */
420 void
421 job_print_summary(struct cmdq_item *item, int blank)
422 {
423 	struct job	*job;
424 	u_int		 n = 0;
425 
426 	LIST_FOREACH(job, &all_jobs, entry) {
427 		if (blank) {
428 			cmdq_print(item, "%s", "");
429 			blank = 0;
430 		}
431 		cmdq_print(item, "Job %u: %s [fd=%d, pid=%ld, status=%d]",
432 		    n, job->cmd, job->fd, (long)job->pid, job->status);
433 		n++;
434 	}
435 }
436