xref: /freebsd/bin/pwait/pwait.c (revision 031beb4e239bfce798af17f5fe8dba8bcaf13d99)
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 #include <sys/types.h>
36 #include <sys/event.h>
37 #include <sys/time.h>
38 #include <sys/wait.h>
39 
40 #include <err.h>
41 #include <errno.h>
42 #include <signal.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <sysexits.h>
47 #include <unistd.h>
48 
49 static void
50 usage(void)
51 {
52 
53 	fprintf(stderr, "usage: pwait [-t timeout] [-ov] pid ...\n");
54 	exit(EX_USAGE);
55 }
56 
57 /*
58  * pwait - wait for processes to terminate
59  */
60 int
61 main(int argc, char *argv[])
62 {
63 	struct itimerval itv;
64 	struct kevent *e;
65 	int oflag, tflag, verbose;
66 	int i, kq, n, nleft, opt, status;
67 	long pid;
68 	char *end, *s;
69 	double timeout;
70 
71 	oflag = 0;
72 	tflag = 0;
73 	verbose = 0;
74 	memset(&itv, 0, sizeof(itv));
75 
76 	while ((opt = getopt(argc, argv, "ot:v")) != -1) {
77 		switch (opt) {
78 		case 'o':
79 			oflag = 1;
80 			break;
81 		case 't':
82 			tflag = 1;
83 			errno = 0;
84 			timeout = strtod(optarg, &end);
85 			if (end == optarg || errno == ERANGE || timeout < 0) {
86 				errx(EX_DATAERR, "timeout value");
87 			}
88 			switch(*end) {
89 			case 0:
90 			case 's':
91 				break;
92 			case 'h':
93 				timeout *= 60;
94 				/* FALLTHROUGH */
95 			case 'm':
96 				timeout *= 60;
97 				break;
98 			default:
99 				errx(EX_DATAERR, "timeout unit");
100 			}
101 			if (timeout > 100000000L) {
102 				errx(EX_DATAERR, "timeout value");
103 			}
104 			itv.it_value.tv_sec = (time_t)timeout;
105 			timeout -= (time_t)timeout;
106 			itv.it_value.tv_usec =
107 			    (suseconds_t)(timeout * 1000000UL);
108 			break;
109 		case 'v':
110 			verbose = 1;
111 			break;
112 		default:
113 			usage();
114 			/* NOTREACHED */
115 		}
116 	}
117 
118 	argc -= optind;
119 	argv += optind;
120 
121 	if (argc == 0) {
122 		usage();
123 	}
124 
125 	kq = kqueue();
126 	if (kq == -1) {
127 		err(EX_OSERR, "kqueue");
128 	}
129 
130 	e = malloc((argc + tflag) * sizeof(struct kevent));
131 	if (e == NULL) {
132 		err(EX_OSERR, "malloc");
133 	}
134 	nleft = 0;
135 	for (n = 0; n < argc; n++) {
136 		s = argv[n];
137 		/* Undocumented Solaris compat */
138 		if (!strncmp(s, "/proc/", 6)) {
139 			s += 6;
140 		}
141 		errno = 0;
142 		pid = strtol(s, &end, 10);
143 		if (pid < 0 || *end != '\0' || errno != 0) {
144 			warnx("%s: bad process id", s);
145 			continue;
146 		}
147 		if (pid == getpid()) {
148 			warnx("%s: skipping my own pid", s);
149 			continue;
150 		}
151 		for (i = 0; i < nleft; i++) {
152 			if (e[i].ident == (uintptr_t)pid) {
153 				break;
154 			}
155 		}
156 		if (i < nleft) {
157 			/* Duplicate. */
158 			continue;
159 		}
160 		EV_SET(e + nleft, pid, EVFILT_PROC, EV_ADD, NOTE_EXIT, 0, NULL);
161 		if (kevent(kq, e + nleft, 1, NULL, 0, NULL) == -1) {
162 			warn("%ld", pid);
163 			if (oflag) {
164 				exit(EX_OK);
165 			}
166 		} else {
167 			nleft++;
168 		}
169 	}
170 
171 	if (nleft > 0 && tflag) {
172 		/*
173 		 * Explicitly detect SIGALRM so that an exit status of 124
174 		 * can be returned rather than 142.
175 		 */
176 		EV_SET(e + nleft, SIGALRM, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL);
177 		if (kevent(kq, e + nleft, 1, NULL, 0, NULL) == -1) {
178 			err(EX_OSERR, "kevent");
179 		}
180 		/* Ignore SIGALRM to not interrupt kevent(2). */
181 		signal(SIGALRM, SIG_IGN);
182 		if (setitimer(ITIMER_REAL, &itv, NULL) == -1) {
183 			err(EX_OSERR, "setitimer");
184 		}
185 	}
186 	while (nleft > 0) {
187 		n = kevent(kq, NULL, 0, e, nleft + tflag, NULL);
188 		if (n == -1) {
189 			err(EX_OSERR, "kevent");
190 		}
191 		for (i = 0; i < n; i++) {
192 			if (e[i].filter == EVFILT_SIGNAL) {
193 				if (verbose) {
194 					printf("timeout\n");
195 				}
196 				exit(124);
197 			}
198 			if (verbose) {
199 				status = e[i].data;
200 				if (WIFEXITED(status)) {
201 					printf("%ld: exited with status %d.\n",
202 					    (long)e[i].ident,
203 					    WEXITSTATUS(status));
204 				} else if (WIFSIGNALED(status)) {
205 					printf("%ld: killed by signal %d.\n",
206 					    (long)e[i].ident,
207 					    WTERMSIG(status));
208 				} else {
209 					printf("%ld: terminated.\n",
210 					    (long)e[i].ident);
211 				}
212 			}
213 			if (oflag) {
214 				exit(EX_OK);
215 			}
216 			--nleft;
217 		}
218 	}
219 
220 	exit(EX_OK);
221 }
222