xref: /freebsd/bin/pwait/pwait.c (revision d37eb51047221dc3322b34db1038ff3aa533883f)
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/types.h>
35 #include <sys/event.h>
36 #include <sys/time.h>
37 #include <sys/wait.h>
38 
39 #include <err.h>
40 #include <errno.h>
41 #include <signal.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <sysexits.h>
46 #include <unistd.h>
47 
48 static void
49 usage(void)
50 {
51 
52 	fprintf(stderr, "usage: pwait [-t timeout] [-ov] pid ...\n");
53 	exit(EX_USAGE);
54 }
55 
56 /*
57  * pwait - wait for processes to terminate
58  */
59 int
60 main(int argc, char *argv[])
61 {
62 	struct itimerval itv;
63 	struct kevent *e;
64 	int oflag, tflag, verbose;
65 	int i, kq, n, nleft, opt, status;
66 	long pid;
67 	char *end, *s;
68 	double timeout;
69 
70 	oflag = 0;
71 	tflag = 0;
72 	verbose = 0;
73 	memset(&itv, 0, sizeof(itv));
74 
75 	while ((opt = getopt(argc, argv, "ot:v")) != -1) {
76 		switch (opt) {
77 		case 'o':
78 			oflag = 1;
79 			break;
80 		case 't':
81 			tflag = 1;
82 			errno = 0;
83 			timeout = strtod(optarg, &end);
84 			if (end == optarg || errno == ERANGE || timeout < 0) {
85 				errx(EX_DATAERR, "timeout value");
86 			}
87 			switch(*end) {
88 			case 0:
89 			case 's':
90 				break;
91 			case 'h':
92 				timeout *= 60;
93 				/* FALLTHROUGH */
94 			case 'm':
95 				timeout *= 60;
96 				break;
97 			default:
98 				errx(EX_DATAERR, "timeout unit");
99 			}
100 			if (timeout > 100000000L) {
101 				errx(EX_DATAERR, "timeout value");
102 			}
103 			itv.it_value.tv_sec = (time_t)timeout;
104 			timeout -= (time_t)timeout;
105 			itv.it_value.tv_usec =
106 			    (suseconds_t)(timeout * 1000000UL);
107 			break;
108 		case 'v':
109 			verbose = 1;
110 			break;
111 		default:
112 			usage();
113 			/* NOTREACHED */
114 		}
115 	}
116 
117 	argc -= optind;
118 	argv += optind;
119 
120 	if (argc == 0) {
121 		usage();
122 	}
123 
124 	kq = kqueue();
125 	if (kq == -1) {
126 		err(EX_OSERR, "kqueue");
127 	}
128 
129 	e = malloc((argc + tflag) * sizeof(struct kevent));
130 	if (e == NULL) {
131 		err(EX_OSERR, "malloc");
132 	}
133 	nleft = 0;
134 	for (n = 0; n < argc; n++) {
135 		s = argv[n];
136 		/* Undocumented Solaris compat */
137 		if (!strncmp(s, "/proc/", 6)) {
138 			s += 6;
139 		}
140 		errno = 0;
141 		pid = strtol(s, &end, 10);
142 		if (pid < 0 || *end != '\0' || errno != 0) {
143 			warnx("%s: bad process id", s);
144 			continue;
145 		}
146 		if (pid == getpid()) {
147 			warnx("%s: skipping my own pid", s);
148 			continue;
149 		}
150 		for (i = 0; i < nleft; i++) {
151 			if (e[i].ident == (uintptr_t)pid) {
152 				break;
153 			}
154 		}
155 		if (i < nleft) {
156 			/* Duplicate. */
157 			continue;
158 		}
159 		EV_SET(e + nleft, pid, EVFILT_PROC, EV_ADD, NOTE_EXIT, 0, NULL);
160 		if (kevent(kq, e + nleft, 1, NULL, 0, NULL) == -1) {
161 			warn("%ld", pid);
162 			if (oflag) {
163 				exit(EX_OK);
164 			}
165 		} else {
166 			nleft++;
167 		}
168 	}
169 
170 	if (nleft > 0 && tflag) {
171 		/*
172 		 * Explicitly detect SIGALRM so that an exit status of 124
173 		 * can be returned rather than 142.
174 		 */
175 		EV_SET(e + nleft, SIGALRM, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL);
176 		if (kevent(kq, e + nleft, 1, NULL, 0, NULL) == -1) {
177 			err(EX_OSERR, "kevent");
178 		}
179 		/* Ignore SIGALRM to not interrupt kevent(2). */
180 		signal(SIGALRM, SIG_IGN);
181 		if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
182 			err(EX_OSERR, "setitimer");
183 		}
184 	}
185 	while (nleft > 0) {
186 		n = kevent(kq, NULL, 0, e, nleft + tflag, NULL);
187 		if (n == -1) {
188 			err(EX_OSERR, "kevent");
189 		}
190 		for (i = 0; i < n; i++) {
191 			if (e[i].filter == EVFILT_SIGNAL) {
192 				if (verbose) {
193 					printf("timeout\n");
194 				}
195 				exit(124);
196 			}
197 			if (verbose) {
198 				status = e[i].data;
199 				if (WIFEXITED(status)) {
200 					printf("%ld: exited with status %d.\n",
201 					    (long)e[i].ident,
202 					    WEXITSTATUS(status));
203 				} else if (WIFSIGNALED(status)) {
204 					printf("%ld: killed by signal %d.\n",
205 					    (long)e[i].ident,
206 					    WTERMSIG(status));
207 				} else {
208 					printf("%ld: terminated.\n",
209 					    (long)e[i].ident);
210 				}
211 			}
212 			if (oflag) {
213 				exit(EX_OK);
214 			}
215 			--nleft;
216 		}
217 	}
218 
219 	exit(EX_OK);
220 }
221