2 * Copyright (c) 1992, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
33 * @(#) Copyright (c) 1992, 1993 The Regents of the University of California. All rights reserved.
34 * @(#)gcore.c 8.2 (Berkeley) 9/23/93
35 * $FreeBSD: src/usr.bin/gcore/gcore.c,v 1.15.2.2 2001/08/17 20:56:22 mikeh Exp $
36 * $DragonFly: src/usr.bin/gcore/gcore.c,v 1.9 2007/02/16 23:11:40 corecode Exp $
40 * Originally written by Eric Cooper in Fall 1981.
41 * Inspired by a version 6 program by Len Levin, 1978.
42 * Several pieces of code lifted from Bill Joy's 4BSD ps.
43 * Most recently, hacked beyond recognition for 4.4BSD by Steven McCanne,
44 * Lawrence Berkeley Laboratory.
46 * Portions of this software were developed by the Computer Systems
47 * Engineering group at Lawrence Berkeley Laboratory under DARPA
48 * contract BG 91-66 and contributed to Berkeley.
50 #include <sys/param.h>
54 #include <sys/sysctl.h>
55 #include <machine/elf.h>
57 #include <machine/vmparam.h>
72 static void core(int, int, struct kinfo_proc *);
73 static void datadump(int, int, pid_t, u_long, int);
74 static void killed(int);
75 static void restart_target(void);
76 static void usage(void) __dead2;
77 static void userdump(int, pid_t, u_long, int);
81 static int data_offset;
85 main(int argc, char **argv)
87 struct kinfo_proc *ki = NULL;
89 int ch, cnt, efd, fd, sflag, uid;
90 char *binfile, *corefile;
91 char errbuf[_POSIX2_LINE_MAX], fname[MAXPATHLEN + 1];
96 while ((ch = getopt(argc, argv, "c:s")) != -1) {
112 /* XXX we should check that the pid argument is really a number */
116 asprintf(&binfile, "/proc/%d/file", pid);
118 errx(1, "allocation failure");
128 efd = open(binfile, O_RDONLY, 0);
130 err(1, "%s", binfile);
132 cnt = read(efd, &exec, sizeof(exec));
133 if (cnt != sizeof(exec))
134 errx(1, "%s exec header: %s",
135 binfile, cnt > 0 ? strerror(EIO) : strerror(errno));
136 if (!N_BADMAG(exec)) {
139 * This legacy a.out support uses the kvm interface instead
142 kd = kvm_openfiles(0, 0, 0, O_RDONLY, errbuf);
144 errx(1, "%s", errbuf);
148 ki = kvm_getprocs(kd, KERN_PROC_PID, pid, &cnt);
149 if (ki == NULL || cnt != 1)
150 errx(1, "%d: not found", pid);
152 if (ki->kp_ruid != uid && uid != 0)
153 errx(1, "%d: not owner", pid);
155 if (ki->kp_flags & P_ZOMBIE)
156 errx(1, "%d: zombie", pid);
158 if (ki->kp_flags & P_WEXIT)
159 errx(1, "%d: process exiting", pid);
160 if (ki->kp_flags & P_SYSTEM) /* Swapper or pagedaemon. */
161 errx(1, "%d: system process", pid);
162 if (exec.a_text != ptoa(ki->kp_vm_tsize))
163 errx(1, "The executable %s does not belong to"
165 "Text segment size (in bytes): executable %ld,"
166 " process %d", binfile, pid, exec.a_text,
167 ptoa(ki->kp_vm_tsize));
168 data_offset = N_DATOFF(exec);
169 } else if (IS_ELF(*(Elf_Ehdr *)&exec)) {
173 errx(1, "Invalid executable file");
175 if (corefile == NULL) {
176 (void)snprintf(fname, sizeof(fname), "core.%d", pid);
179 fd = open(corefile, O_RDWR|O_CREAT|O_TRUNC, DEFFILEMODE);
181 err(1, "%s", corefile);
184 signal(SIGHUP, killed);
185 signal(SIGINT, killed);
186 signal(SIGTERM, killed);
187 if (kill(pid, SIGSTOP) == -1)
188 err(1, "%d: stop signal", pid);
189 atexit(restart_target);
195 elf_coredump(fd, pid);
203 * Build the core file.
206 core(int efd, int fd, struct kinfo_proc *ki)
210 char ubytes[ctob(UPAGES)];
212 int tsize = ki->kp_vm_tsize;
213 int dsize = ki->kp_vm_dsize;
214 int ssize = ki->kp_vm_ssize;
217 /* Read in user struct */
218 cnt = kvm_read(kd, ki->kp_pid, &uarea, sizeof(uarea));
219 if (cnt != sizeof(uarea))
220 errx(1, "read user structure: %s",
221 cnt > 0 ? strerror(EIO) : strerror(errno));
224 * Fill in the eproc vm parameters, since these are garbage unless
225 * the kernel is dumping core or something.
227 uarea.user.u_kproc = *ki;
230 cnt = write(fd, &uarea, sizeof(uarea));
231 if (cnt != sizeof(uarea))
232 errx(1, "write user structure: %s",
233 cnt > 0 ? strerror(EIO) : strerror(errno));
235 /* Dump data segment */
236 datadump(efd, fd, ki->kp_pid, USRTEXT + ctob(tsize), dsize);
238 /* Dump stack segment */
239 userdump(fd, ki->kp_pid, USRSTACK - ctob(ssize), ssize);
241 /* Dump machine dependent portions of the core. */
246 datadump(int efd, int fd, pid_t pid,
247 u_long addr, int npage)
250 char buffer[PAGE_SIZE];
252 delta = data_offset - addr;
253 while (--npage >= 0) {
254 cc = kvm_uread(kd, pid, addr, buffer, PAGE_SIZE);
255 if (cc != PAGE_SIZE) {
256 /* Try to read the page from the executable. */
257 if (lseek(efd, (off_t)addr + delta, SEEK_SET) == -1)
258 err(1, "seek executable: %s", strerror(errno));
259 cc = read(efd, buffer, sizeof(buffer));
260 if (cc != sizeof(buffer)) {
262 err(1, "read executable");
263 else /* Assume untouched bss page. */
264 bzero(buffer, sizeof(buffer));
267 cc = write(fd, buffer, PAGE_SIZE);
269 errx(1, "write data segment: %s",
270 cc > 0 ? strerror(EIO) : strerror(errno));
279 signal(sig, SIG_DFL);
290 userdump(int fd, pid_t pid, u_long addr,
294 char buffer[PAGE_SIZE];
296 while (--npage >= 0) {
297 cc = kvm_uread(kd, pid, addr, buffer, PAGE_SIZE);
299 /* Could be an untouched fill-with-zero page. */
300 bzero(buffer, PAGE_SIZE);
301 cc = write(fd, buffer, PAGE_SIZE);
303 errx(1, "write stack segment: %s",
304 cc > 0 ? strerror(EIO) : strerror(errno));
312 (void)fprintf(stderr, "usage: gcore [-s] [-c core] [executable] pid\n");