xref: /freebsd/usr.bin/gcore/gcore.c (revision a0409676120c1e558d0ade943019934e0f15118d)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
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  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef lint
33 static const char copyright[] =
34 "@(#) Copyright (c) 1992, 1993\n\
35 	The Regents of the University of California.  All rights reserved.\n";
36 #endif /* not lint */
37 
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)gcore.c	8.2 (Berkeley) 9/23/93";
41 #endif /* not lint */
42 #endif
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
45 
46 /*
47  * Originally written by Eric Cooper in Fall 1981.
48  * Inspired by a version 6 program by Len Levin, 1978.
49  * Several pieces of code lifted from Bill Joy's 4BSD ps.
50  * Most recently, hacked beyond recognition for 4.4BSD by Steven McCanne,
51  * Lawrence Berkeley Laboratory.
52  *
53  * Portions of this software were developed by the Computer Systems
54  * Engineering group at Lawrence Berkeley Laboratory under DARPA
55  * contract BG 91-66 and contributed to Berkeley.
56  */
57 
58 #include <sys/param.h>
59 #include <sys/time.h>
60 #include <sys/stat.h>
61 #include <sys/linker_set.h>
62 #include <sys/sysctl.h>
63 
64 #include <err.h>
65 #include <fcntl.h>
66 #include <stdio.h>
67 #include <stdlib.h>
68 #include <string.h>
69 #include <unistd.h>
70 
71 #include "extern.h"
72 int pflags;
73 
74 static void	killed(int);
75 static void	usage(void) __dead2;
76 
77 static pid_t pid;
78 
79 SET_DECLARE(dumpset, struct dumpers);
80 
81 int
82 main(int argc, char *argv[])
83 {
84 	int ch, efd, fd, name[4];
85 	char *binfile, *corefile;
86 	char passpath[MAXPATHLEN], fname[MAXPATHLEN];
87 	struct dumpers **d, *dumper;
88 	size_t len;
89 
90 	pflags = 0;
91 	corefile = NULL;
92         while ((ch = getopt(argc, argv, "c:f")) != -1) {
93                 switch (ch) {
94                 case 'c':
95 			corefile = optarg;
96                         break;
97 		case 'f':
98 			pflags |= PFLAGS_FULL;
99 			break;
100 		default:
101 			usage();
102 			break;
103 		}
104 	}
105 	argv += optind;
106 	argc -= optind;
107 	/* XXX we should check that the pid argument is really a number */
108 	switch (argc) {
109 	case 1:
110 		pid = atoi(argv[0]);
111 		name[0] = CTL_KERN;
112 		name[1] = KERN_PROC;
113 		name[2] = KERN_PROC_PATHNAME;
114 		name[3] = pid;
115 		len = sizeof(passpath);
116 		if (sysctl(name, 4, passpath, &len, NULL, 0) == -1)
117 			errx(1, "kern.proc.pathname failure");
118 		binfile = passpath;
119 		break;
120 	case 2:
121 		pid = atoi(argv[1]);
122 		binfile = argv[0];
123 		break;
124 	default:
125 		usage();
126 	}
127 	efd = open(binfile, O_RDONLY, 0);
128 	if (efd < 0)
129 		err(1, "%s", binfile);
130 	dumper = NULL;
131 	SET_FOREACH(d, dumpset) {
132 		lseek(efd, 0, SEEK_SET);
133 		if (((*d)->ident)(efd, pid, binfile)) {
134 			dumper = (*d);
135 			lseek(efd, 0, SEEK_SET);
136 			break;
137 		}
138 	}
139 	if (dumper == NULL)
140 		errx(1, "Invalid executable file");
141 	if (corefile == NULL) {
142 		(void)snprintf(fname, sizeof(fname), "core.%d", pid);
143 		corefile = fname;
144 	}
145 	fd = open(corefile, O_RDWR|O_CREAT|O_TRUNC, DEFFILEMODE);
146 	if (fd < 0)
147 		err(1, "%s", corefile);
148 
149 	dumper->dump(efd, fd, pid);
150 	(void)close(fd);
151 	(void)close(efd);
152 	exit(0);
153 }
154 
155 void
156 usage(void)
157 {
158 
159 	(void)fprintf(stderr, "usage: gcore [-c core] [executable] pid\n");
160 	exit(1);
161 }
162