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 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#ifndef lint
31static const char copyright[] =
32"@(#) Copyright (c) 1992, 1993\n\
33	The Regents of the University of California.  All rights reserved.\n";
34#endif /* not lint */
35
36#if 0
37#ifndef lint
38static char sccsid[] = "@(#)gcore.c	8.2 (Berkeley) 9/23/93";
39#endif /* not lint */
40#endif
41#include <sys/cdefs.h>
42__FBSDID("$FreeBSD$");
43
44/*
45 * Originally written by Eric Cooper in Fall 1981.
46 * Inspired by a version 6 program by Len Levin, 1978.
47 * Several pieces of code lifted from Bill Joy's 4BSD ps.
48 * Most recently, hacked beyond recognition for 4.4BSD by Steven McCanne,
49 * Lawrence Berkeley Laboratory.
50 *
51 * Portions of this software were developed by the Computer Systems
52 * Engineering group at Lawrence Berkeley Laboratory under DARPA
53 * contract BG 91-66 and contributed to Berkeley.
54 */
55
56#include <sys/param.h>
57#include <sys/time.h>
58#include <sys/stat.h>
59#include <sys/linker_set.h>
60#include <sys/sysctl.h>
61
62#include <err.h>
63#include <fcntl.h>
64#include <stdio.h>
65#include <stdlib.h>
66#include <string.h>
67#include <unistd.h>
68
69#include "extern.h"
70int pflags;
71
72static void	killed(int);
73static void	usage(void) __dead2;
74
75static pid_t pid;
76
77SET_DECLARE(dumpset, struct dumpers);
78
79int
80main(int argc, char *argv[])
81{
82	int ch, efd, fd, name[4];
83	char *binfile, *corefile;
84	char passpath[MAXPATHLEN], fname[MAXPATHLEN];
85	struct dumpers **d, *dumper;
86	size_t len;
87
88	pflags = 0;
89	corefile = NULL;
90        while ((ch = getopt(argc, argv, "c:fs")) != -1) {
91                switch (ch) {
92                case 'c':
93			corefile = optarg;
94                        break;
95		case 'f':
96			pflags |= PFLAGS_FULL;
97			break;
98		case 's':
99			pflags |= PFLAGS_RESUME;
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		name[0] = CTL_KERN;
113		name[1] = KERN_PROC;
114		name[2] = KERN_PROC_PATHNAME;
115		name[3] = pid;
116		len = sizeof(passpath);
117		if (sysctl(name, 4, passpath, &len, NULL, 0) == -1)
118			errx(1, "kern.proc.pathname failure");
119		binfile = passpath;
120		break;
121	case 2:
122		pid = atoi(argv[1]);
123		binfile = argv[0];
124		break;
125	default:
126		usage();
127	}
128	efd = open(binfile, O_RDONLY, 0);
129	if (efd < 0)
130		err(1, "%s", binfile);
131	dumper = NULL;
132	SET_FOREACH(d, dumpset) {
133		lseek(efd, 0, SEEK_SET);
134		if (((*d)->ident)(efd, pid, binfile)) {
135			dumper = (*d);
136			lseek(efd, 0, SEEK_SET);
137			break;
138		}
139	}
140	if (dumper == NULL)
141		errx(1, "Invalid executable file");
142	if (corefile == NULL) {
143		(void)snprintf(fname, sizeof(fname), "core.%d", pid);
144		corefile = fname;
145	}
146	fd = open(corefile, O_RDWR|O_CREAT|O_TRUNC, DEFFILEMODE);
147	if (fd < 0)
148		err(1, "%s", corefile);
149	/*
150	 * The semantics of the 's' flag is to stop the target process.
151	 * Previous versions of gcore would manage this by trapping SIGHUP,
152	 * SIGINT and SIGTERM (to be passed to the target pid), and then
153	 * signal the child to stop.
154	 *
155	 * However, this messes up if the selected dumper uses ptrace calls
156	 * that leave the child already stopped. The waitpid call in elfcore
157	 * never returns.
158	 *
159	 * The best thing to do here is to externalize the 's' flag and let
160	 * each dumper dispose of what that means, if anything. For the elfcore
161	 * dumper, the 's' flag is a no-op since the ptrace attach stops the
162	 * process in question already.
163	 */
164
165	dumper->dump(efd, fd, pid);
166	(void)close(fd);
167	(void)close(efd);
168	exit(0);
169}
170
171void
172usage(void)
173{
174
175	(void)fprintf(stderr, "usage: gcore [-s] [-c core] [executable] pid\n");
176	exit(1);
177}
178