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
33static 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
40static 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/ptrace.h>
60#include <sys/time.h>
61#include <sys/stat.h>
62#include <sys/linker_set.h>
63#include <sys/sysctl.h>
64#include <sys/wait.h>
65
66#include <err.h>
67#include <fcntl.h>
68#include <stdbool.h>
69#include <stdio.h>
70#include <stdlib.h>
71#include <string.h>
72#include <unistd.h>
73
74#include "extern.h"
75int pflags;
76
77static void	killed(int);
78static void	usage(void) __dead2;
79
80static pid_t pid;
81static bool kflag = false;
82
83SET_DECLARE(dumpset, struct dumpers);
84
85static int
86open_corefile(char *corefile)
87{
88	char fname[MAXPATHLEN];
89	int fd;
90
91	if (corefile == NULL) {
92		(void)snprintf(fname, sizeof(fname), "core.%d", pid);
93		corefile = fname;
94	}
95	fd = open(corefile, O_RDWR | O_CREAT | O_TRUNC, DEFFILEMODE);
96	if (fd < 0)
97		err(1, "%s", corefile);
98	return (fd);
99}
100
101static void
102kcoredump(int fd, pid_t pid)
103{
104	struct ptrace_coredump pc;
105	int error, res, ret, waited;
106
107	error = ptrace(PT_ATTACH, pid, NULL, 0);
108	if (error != 0)
109		err(1, "attach");
110
111	waited = waitpid(pid, &res, 0);
112	if (waited == -1)
113		err(1, "wait for STOP");
114
115	ret = 0;
116	memset(&pc, 0, sizeof(pc));
117	pc.pc_fd = fd;
118	pc.pc_flags = (pflags & PFLAGS_FULL) != 0 ? PC_ALL : 0;
119	error = ptrace(PT_COREDUMP, pid, (void *)&pc, sizeof(pc));
120	if (error == -1) {
121		warn("coredump");
122		ret = 1;
123	}
124
125	waited = waitpid(pid, &res, WNOHANG);
126	if (waited == -1) {
127		warn("wait after coredump");
128		ret = 1;
129	}
130
131	error = ptrace(PT_DETACH, pid, NULL, 0);
132	if (error == -1) {
133		warn("detach failed, check process status");
134		ret = 1;
135	}
136
137	exit(ret);
138}
139
140int
141main(int argc, char *argv[])
142{
143	int ch, efd, fd, name[4];
144	char *binfile, *corefile;
145	char passpath[MAXPATHLEN];
146	struct dumpers **d, *dumper;
147	size_t len;
148
149	pflags = 0;
150	corefile = NULL;
151        while ((ch = getopt(argc, argv, "c:fk")) != -1) {
152                switch (ch) {
153                case 'c':
154			corefile = optarg;
155                        break;
156		case 'f':
157			pflags |= PFLAGS_FULL;
158			break;
159		case 'k':
160			kflag = true;
161			break;
162		default:
163			usage();
164			break;
165		}
166	}
167	argv += optind;
168	argc -= optind;
169
170	/* XXX we should check that the pid argument is really a number */
171	switch (argc) {
172	case 1:
173		pid = atoi(argv[0]);
174		break;
175	case 2:
176		binfile = argv[0];
177		pid = atoi(argv[1]);
178		break;
179	default:
180		usage();
181	}
182
183	if (kflag) {
184		fd = open_corefile(corefile);
185		kcoredump(fd, pid);
186	}
187
188	if (argc == 1) {
189		name[0] = CTL_KERN;
190		name[1] = KERN_PROC;
191		name[2] = KERN_PROC_PATHNAME;
192		name[3] = pid;
193		len = sizeof(passpath);
194		if (sysctl(name, 4, passpath, &len, NULL, 0) == -1)
195			errx(1, "kern.proc.pathname failure");
196		binfile = passpath;
197	}
198	efd = open(binfile, O_RDONLY, 0);
199	if (efd < 0)
200		err(1, "%s", binfile);
201	dumper = NULL;
202	SET_FOREACH(d, dumpset) {
203		lseek(efd, 0, SEEK_SET);
204		if (((*d)->ident)(efd, pid, binfile)) {
205			dumper = (*d);
206			lseek(efd, 0, SEEK_SET);
207			break;
208		}
209	}
210	if (dumper == NULL)
211		errx(1, "Invalid executable file");
212	fd = open_corefile(corefile);
213
214	dumper->dump(efd, fd, pid);
215	(void)close(fd);
216	(void)close(efd);
217	exit(0);
218}
219
220void
221usage(void)
222{
223
224	(void)fprintf(stderr,
225	    "usage: gcore [-kf] [-c core] [executable] pid\n");
226	exit(1);
227}
228