xref: /freebsd/usr.bin/gcore/gcore.c (revision 39beb93c3f8bdbf72a61fda42300b5ebed7390c8)
1 /*-
2  * Copyright (c) 1992, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1992, 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #if 0
41 #ifndef lint
42 static char sccsid[] = "@(#)gcore.c	8.2 (Berkeley) 9/23/93";
43 #endif /* not lint */
44 #endif
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
47 
48 /*
49  * Originally written by Eric Cooper in Fall 1981.
50  * Inspired by a version 6 program by Len Levin, 1978.
51  * Several pieces of code lifted from Bill Joy's 4BSD ps.
52  * Most recently, hacked beyond recognition for 4.4BSD by Steven McCanne,
53  * Lawrence Berkeley Laboratory.
54  *
55  * Portions of this software were developed by the Computer Systems
56  * Engineering group at Lawrence Berkeley Laboratory under DARPA
57  * contract BG 91-66 and contributed to Berkeley.
58  */
59 
60 #include <sys/param.h>
61 #include <sys/time.h>
62 #include <sys/stat.h>
63 #include <sys/linker_set.h>
64 
65 #include <err.h>
66 #include <fcntl.h>
67 #include <signal.h>
68 #include <stdio.h>
69 #include <stdlib.h>
70 #include <string.h>
71 #include <unistd.h>
72 
73 #include "extern.h"
74 
75 static void	killed(int);
76 static void	restart_target(void);
77 static void	usage(void) __dead2;
78 
79 static pid_t pid;
80 
81 SET_DECLARE(dumpset, struct dumpers);
82 
83 int
84 main(int argc, char *argv[])
85 {
86 	int ch, efd, fd, sflag;
87 	char *binfile, *corefile;
88 	char fname[MAXPATHLEN];
89 	struct dumpers **d, *dumper;
90 
91 	sflag = 0;
92 	corefile = NULL;
93         while ((ch = getopt(argc, argv, "c:s")) != -1) {
94                 switch (ch) {
95                 case 'c':
96 			corefile = optarg;
97                         break;
98 		case 's':
99 			sflag = 1;
100 			break;
101 		default:
102 			usage();
103 			break;
104 		}
105 	}
106 	argv += optind;
107 	argc -= optind;
108 	/* XXX we should check that the pid argument is really a number */
109 	switch (argc) {
110 	case 1:
111 		pid = atoi(argv[0]);
112 		asprintf(&binfile, "/proc/%d/file", pid);
113 		if (binfile == NULL)
114 			errx(1, "allocation failure");
115 		break;
116 	case 2:
117 		pid = atoi(argv[1]);
118 		binfile = argv[0];
119 		break;
120 	default:
121 		usage();
122 	}
123 	efd = open(binfile, O_RDONLY, 0);
124 	if (efd < 0)
125 		err(1, "%s", binfile);
126 	dumper = NULL;
127 	SET_FOREACH(d, dumpset) {
128 		lseek(efd, 0, SEEK_SET);
129 		if (((*d)->ident)(efd, pid, binfile)) {
130 			dumper = (*d);
131 			lseek(efd, 0, SEEK_SET);
132 			break;
133 		}
134 	}
135 	if (dumper == NULL)
136 		errx(1, "Invalid executable file");
137 	if (corefile == NULL) {
138 		(void)snprintf(fname, sizeof(fname), "core.%d", pid);
139 		corefile = fname;
140 	}
141 	fd = open(corefile, O_RDWR|O_CREAT|O_TRUNC, DEFFILEMODE);
142 	if (fd < 0)
143 		err(1, "%s", corefile);
144 	if (sflag) {
145 		signal(SIGHUP, killed);
146 		signal(SIGINT, killed);
147 		signal(SIGTERM, killed);
148 		if (kill(pid, SIGSTOP) == -1)
149 			err(1, "%d: stop signal", pid);
150 		atexit(restart_target);
151 	}
152 	dumper->dump(efd, fd, pid);
153 	(void)close(fd);
154 	(void)close(efd);
155 	exit(0);
156 }
157 
158 static void
159 killed(int sig)
160 {
161 
162 	restart_target();
163 	signal(sig, SIG_DFL);
164 	kill(getpid(), sig);
165 }
166 
167 static void
168 restart_target(void)
169 {
170 
171 	kill(pid, SIGCONT);
172 }
173 
174 void
175 usage(void)
176 {
177 
178 	(void)fprintf(stderr, "usage: gcore [-s] [-c core] [executable] pid\n");
179 	exit(1);
180 }
181