xref: /freebsd/bin/timeout/timeout.c (revision 05427f4639bcf2703329a9be9d25ec09bb782742)
1 /*-
2  * Copyright (c) 2014 Baptiste Daroussin <bapt@FreeBSD.org>
3  * Copyright (c) 2014 Vsevolod Stakhov <vsevolod@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer
11  *    in this position and unchanged.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 #include <sys/procctl.h>
30 #include <sys/time.h>
31 #include <sys/wait.h>
32 
33 #include <err.h>
34 #include <errno.h>
35 #include <getopt.h>
36 #include <signal.h>
37 #include <stdbool.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <unistd.h>
42 
43 #define EXIT_TIMEOUT 124
44 #define EXIT_INVALID 125
45 #define EXIT_CMD_ERROR 126
46 #define EXIT_CMD_NOENT 127
47 
48 static sig_atomic_t sig_chld = 0;
49 static sig_atomic_t sig_term = 0;
50 static sig_atomic_t sig_alrm = 0;
51 static sig_atomic_t sig_ign = 0;
52 
53 static void
54 usage(void)
55 {
56 
57 	fprintf(stderr, "Usage: %s [-k time | --kill-after time]"
58 	    " [-s sig | --signal sig] [--foreground] [--preserve-status]"
59 	    " <duration> <command> <arg ...>\n", getprogname());
60 
61 	exit(EXIT_FAILURE);
62 }
63 
64 static double
65 parse_duration(const char *duration)
66 {
67 	double ret;
68 	char *end;
69 
70 	ret = strtod(duration, &end);
71 	if (ret == 0 && end == duration)
72 		errx(EXIT_INVALID, "invalid duration");
73 
74 	if (end == NULL || *end == '\0')
75 		return (ret);
76 
77 	if (end != NULL && *(end + 1) != '\0')
78 		errx(EXIT_INVALID, "invalid duration");
79 
80 	switch (*end) {
81 	case 's':
82 		break;
83 	case 'm':
84 		ret *= 60;
85 		break;
86 	case 'h':
87 		ret *= 60 * 60;
88 		break;
89 	case 'd':
90 		ret *= 60 * 60 * 24;
91 		break;
92 	default:
93 		errx(EXIT_INVALID, "invalid duration");
94 	}
95 
96 	if (ret < 0 || ret >= 100000000UL)
97 		errx(EXIT_INVALID, "invalid duration");
98 
99 	return (ret);
100 }
101 
102 static int
103 parse_signal(const char *str)
104 {
105 	int sig, i;
106 	const char *errstr;
107 
108 	sig = strtonum(str, 1, sys_nsig - 1, &errstr);
109 
110 	if (errstr == NULL)
111 		return (sig);
112 
113 	if (strncasecmp(str, "SIG", 3) == 0)
114 		str += 3;
115 
116 	for (i = 1; i < sys_nsig; i++) {
117 		if (strcasecmp(str, sys_signame[i]) == 0)
118 			return (i);
119 	}
120 
121 	errx(EXIT_INVALID, "invalid signal");
122 }
123 
124 static void
125 sig_handler(int signo)
126 {
127 	if (sig_ign != 0 && signo == sig_ign) {
128 		sig_ign = 0;
129 		return;
130 	}
131 
132 	switch (signo) {
133 	case 0:
134 	case SIGINT:
135 	case SIGHUP:
136 	case SIGQUIT:
137 	case SIGTERM:
138 		sig_term = signo;
139 		break;
140 	case SIGCHLD:
141 		sig_chld = 1;
142 		break;
143 	case SIGALRM:
144 		sig_alrm = 1;
145 		break;
146 	}
147 }
148 
149 static void
150 set_interval(double iv)
151 {
152 	struct itimerval tim;
153 
154 	memset(&tim, 0, sizeof(tim));
155 	tim.it_value.tv_sec = (time_t)iv;
156 	iv -= (double)tim.it_value.tv_sec;
157 	tim.it_value.tv_usec = (suseconds_t)(iv * 1000000UL);
158 
159 	if (setitimer(ITIMER_REAL, &tim, NULL) == -1)
160 		err(EXIT_FAILURE, "setitimer()");
161 }
162 
163 int
164 main(int argc, char **argv)
165 {
166 	int ch;
167 	int foreground, preserve;
168 	int error, pstat, status;
169 	int killsig = SIGTERM;
170 	size_t i;
171 	pid_t pid, cpid;
172 	double first_kill;
173 	double second_kill;
174 	bool timedout = false;
175 	bool do_second_kill = false;
176 	bool child_done = false;
177 	struct sigaction signals;
178 	struct procctl_reaper_status info;
179 	struct procctl_reaper_kill killemall;
180 	int signums[] = {
181 		-1,
182 		SIGTERM,
183 		SIGINT,
184 		SIGHUP,
185 		SIGCHLD,
186 		SIGALRM,
187 		SIGQUIT,
188 	};
189 
190 	foreground = preserve = 0;
191 	second_kill = 0;
192 
193 	const struct option longopts[] = {
194 		{ "preserve-status", no_argument,       &preserve,    1 },
195 		{ "foreground",      no_argument,       &foreground,  1 },
196 		{ "kill-after",      required_argument, NULL,        'k'},
197 		{ "signal",          required_argument, NULL,        's'},
198 		{ "help",            no_argument,       NULL,        'h'},
199 		{ NULL,              0,                 NULL,         0 }
200 	};
201 
202 	while ((ch = getopt_long(argc, argv, "+k:s:h", longopts, NULL)) != -1) {
203 		switch (ch) {
204 			case 'k':
205 				do_second_kill = true;
206 				second_kill = parse_duration(optarg);
207 				break;
208 			case 's':
209 				killsig = parse_signal(optarg);
210 				break;
211 			case 0:
212 				break;
213 			case 'h':
214 			default:
215 				usage();
216 		}
217 	}
218 
219 	argc -= optind;
220 	argv += optind;
221 
222 	if (argc < 2)
223 		usage();
224 
225 	first_kill = parse_duration(argv[0]);
226 	argc--;
227 	argv++;
228 
229 	if (!foreground) {
230 		/* Acquire a reaper */
231 		if (procctl(P_PID, getpid(), PROC_REAP_ACQUIRE, NULL) == -1)
232 			err(EXIT_FAILURE, "Fail to acquire the reaper");
233 	}
234 
235 	memset(&signals, 0, sizeof(signals));
236 	sigemptyset(&signals.sa_mask);
237 
238 	if (killsig != SIGKILL && killsig != SIGSTOP)
239 		signums[0] = killsig;
240 
241 	for (i = 0; i < sizeof(signums) / sizeof(signums[0]); i++)
242 		sigaddset(&signals.sa_mask, signums[i]);
243 
244 	signals.sa_handler = sig_handler;
245 	signals.sa_flags = SA_RESTART;
246 
247 	for (i = 0; i < sizeof(signums) / sizeof(signums[0]); i++) {
248 		if (signums[i] != -1 && signums[i] != 0 &&
249 		    sigaction(signums[i], &signals, NULL) == -1)
250 			err(EXIT_FAILURE, "sigaction()");
251 	}
252 
253 	/* Don't stop if background child needs TTY */
254 	signal(SIGTTIN, SIG_IGN);
255 	signal(SIGTTOU, SIG_IGN);
256 
257 	pid = fork();
258 	if (pid == -1)
259 		err(EXIT_FAILURE, "fork()");
260 	else if (pid == 0) {
261 		/* child process */
262 		signal(SIGTTIN, SIG_DFL);
263 		signal(SIGTTOU, SIG_DFL);
264 
265 		error = execvp(argv[0], argv);
266 		if (error == -1) {
267 			if (errno == ENOENT)
268 				err(EXIT_CMD_NOENT, "exec(%s)", argv[0]);
269 			else
270 				err(EXIT_CMD_ERROR, "exec(%s)", argv[0]);
271 		}
272 	}
273 
274 	if (sigprocmask(SIG_BLOCK, &signals.sa_mask, NULL) == -1)
275 		err(EXIT_FAILURE, "sigprocmask()");
276 
277 	/* parent continues here */
278 	set_interval(first_kill);
279 
280 	for (;;) {
281 		sigemptyset(&signals.sa_mask);
282 		sigsuspend(&signals.sa_mask);
283 
284 		if (sig_chld) {
285 			sig_chld = 0;
286 
287 			while ((cpid = waitpid(-1, &status, WNOHANG)) != 0) {
288 				if (cpid < 0) {
289 					if (errno == EINTR)
290 						continue;
291 					else
292 						break;
293 				} else if (cpid == pid) {
294 					pstat = status;
295 					child_done = true;
296 				}
297 			}
298 			if (child_done) {
299 				if (foreground) {
300 					break;
301 				} else {
302 					procctl(P_PID, getpid(),
303 					    	PROC_REAP_STATUS, &info);
304 					if (info.rs_children == 0)
305 						break;
306 				}
307 			}
308 		} else if (sig_alrm) {
309 			sig_alrm = 0;
310 
311 			timedout = true;
312 			if (!foreground) {
313 				killemall.rk_sig = killsig;
314 				killemall.rk_flags = 0;
315 				procctl(P_PID, getpid(), PROC_REAP_KILL,
316 				    &killemall);
317 			} else
318 				kill(pid, killsig);
319 
320 			if (do_second_kill) {
321 				set_interval(second_kill);
322 				do_second_kill = false;
323 				sig_ign = killsig;
324 				killsig = SIGKILL;
325 			} else
326 				break;
327 
328 		} else if (sig_term) {
329 			if (!foreground) {
330 				killemall.rk_sig = sig_term;
331 				killemall.rk_flags = 0;
332 				procctl(P_PID, getpid(), PROC_REAP_KILL,
333 				    &killemall);
334 			} else
335 				kill(pid, sig_term);
336 
337 			if (do_second_kill) {
338 				set_interval(second_kill);
339 				do_second_kill = false;
340 				sig_ign = killsig;
341 				killsig = SIGKILL;
342 			} else
343 				break;
344 		}
345 	}
346 
347 	while (!child_done && wait(&pstat) == -1) {
348 		if (errno != EINTR)
349 			err(EXIT_FAILURE, "waitpid()");
350 	}
351 
352 	if (!foreground)
353 		procctl(P_PID, getpid(), PROC_REAP_RELEASE, NULL);
354 
355 	if (WEXITSTATUS(pstat))
356 		pstat = WEXITSTATUS(pstat);
357 	else if (WIFSIGNALED(pstat))
358 		pstat = 128 + WTERMSIG(pstat);
359 
360 	if (timedout && !preserve)
361 		pstat = EXIT_TIMEOUT;
362 
363 	return (pstat);
364 }
365