xref: /freebsd/bin/pwait/pwait.c (revision cbd30a72ca196976c1c700400ecd424baa1b9c16)
1 /*-
2  * Copyright (c) 2004-2009, Jilles Tjoelker
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with
6  * or without modification, are permitted provided that the
7  * following conditions are met:
8  *
9  * 1. Redistributions of source code must retain the above
10  *    copyright notice, this list of conditions and the
11  *    following disclaimer.
12  * 2. Redistributions in binary form must reproduce the
13  *    above copyright notice, this list of conditions and
14  *    the following disclaimer in the documentation and/or
15  *    other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
18  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
19  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
21  * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
22  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY
23  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
26  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
27  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
29  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
30  * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
31  * OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include <sys/types.h>
38 #include <sys/event.h>
39 #include <sys/time.h>
40 #include <sys/wait.h>
41 
42 #include <err.h>
43 #include <errno.h>
44 #include <fcntl.h>
45 #include <signal.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <sysexits.h>
50 #include <unistd.h>
51 
52 static void
53 usage(void)
54 {
55 
56 	fprintf(stderr, "usage: pwait [-t timeout] [-v] pid ...\n");
57 	exit(EX_USAGE);
58 }
59 
60 /*
61  * pwait - wait for processes to terminate
62  */
63 int
64 main(int argc, char *argv[])
65 {
66 	struct itimerval itv;
67 	int kq;
68 	struct kevent *e;
69 	int tflag, verbose;
70 	int opt, nleft, n, i, duplicate, status;
71 	long pid;
72 	char *s, *end;
73 	double timeout;
74 
75 	tflag = verbose = 0;
76 	memset(&itv, 0, sizeof(itv));
77 	while ((opt = getopt(argc, argv, "t:v")) != -1) {
78 		switch (opt) {
79 		case 't':
80 			tflag = 1;
81 			errno = 0;
82 			timeout = strtod(optarg, &end);
83 			if (end == optarg || errno == ERANGE ||
84 			    timeout < 0)
85 				errx(EX_DATAERR, "timeout value");
86 			switch(*end) {
87 			case 0:
88 			case 's':
89 				break;
90 			case 'h':
91 				timeout *= 60;
92 				/* FALLTHROUGH */
93 			case 'm':
94 				timeout *= 60;
95 				break;
96 			default:
97 				errx(EX_DATAERR, "timeout unit");
98 			}
99 			if (timeout > 100000000L)
100 				errx(EX_DATAERR, "timeout value");
101 			itv.it_value.tv_sec = (time_t)timeout;
102 			timeout -= (time_t)timeout;
103 			itv.it_value.tv_usec =
104 			    (suseconds_t)(timeout * 1000000UL);
105 			break;
106 		case 'v':
107 			verbose = 1;
108 			break;
109 		default:
110 			usage();
111 			/* NOTREACHED */
112 		}
113 	}
114 
115 	argc -= optind;
116 	argv += optind;
117 
118 	if (argc == 0)
119 		usage();
120 
121 	kq = kqueue();
122 	if (kq == -1)
123 		err(1, "kqueue");
124 
125 	e = malloc((argc + tflag) * sizeof(struct kevent));
126 	if (e == NULL)
127 		err(1, "malloc");
128 	nleft = 0;
129 	for (n = 0; n < argc; n++) {
130 		s = argv[n];
131 		if (!strncmp(s, "/proc/", 6)) /* Undocumented Solaris compat */
132 			s += 6;
133 		errno = 0;
134 		pid = strtol(s, &end, 10);
135 		if (pid < 0 || *end != '\0' || errno != 0) {
136 			warnx("%s: bad process id", s);
137 			continue;
138 		}
139 		duplicate = 0;
140 		for (i = 0; i < nleft; i++)
141 			if (e[i].ident == (uintptr_t)pid)
142 				duplicate = 1;
143 		if (!duplicate) {
144 			EV_SET(e + nleft, pid, EVFILT_PROC, EV_ADD, NOTE_EXIT,
145 			    0, NULL);
146 			if (kevent(kq, e + nleft, 1, NULL, 0, NULL) == -1)
147 				warn("%ld", pid);
148 			else
149 				nleft++;
150 		}
151 	}
152 
153 	if (tflag) {
154 		/*
155 		 * Explicitly detect SIGALRM so that an exit status of 124
156 		 * can be returned rather than 142.
157 		 */
158 		EV_SET(e + nleft, SIGALRM, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL);
159 		if (kevent(kq, e + nleft, 1, NULL, 0, NULL) == -1)
160 			err(EX_OSERR, "kevent");
161 		/* Ignore SIGALRM to not interrupt kevent(2). */
162 		signal(SIGALRM, SIG_IGN);
163 		if (setitimer(ITIMER_REAL, &itv, NULL) == -1)
164 			err(EX_OSERR, "setitimer");
165 	}
166 	while (nleft > 0) {
167 		n = kevent(kq, NULL, 0, e, nleft + tflag, NULL);
168 		if (n == -1)
169 			err(1, "kevent");
170 		for (i = 0; i < n; i++) {
171 			if (e[i].filter == EVFILT_SIGNAL) {
172 				if (verbose)
173 					printf("timeout\n");
174 				return (124);
175 			}
176 			if (verbose) {
177 				status = e[i].data;
178 				if (WIFEXITED(status))
179 					printf("%ld: exited with status %d.\n",
180 					    (long)e[i].ident,
181 					    WEXITSTATUS(status));
182 				else if (WIFSIGNALED(status))
183 					printf("%ld: killed by signal %d.\n",
184 					    (long)e[i].ident,
185 					    WTERMSIG(status));
186 				else
187 					printf("%ld: terminated.\n",
188 					    (long)e[i].ident);
189 			}
190 			--nleft;
191 		}
192 	}
193 
194 	exit(EX_OK);
195 }
196