NetBSD/usr.bin/ktrace/ktrace.c
itohy 0af9894f2f [ktruss] Use fork(2), not vfork(2).
The child process of do_ktrace() does return and the stack is
changed by another function call (execvp()).
By using vfork() (my previous change), the execution of the parent
process resumes on the modified stack.  Oops.
We could use vfork() carefully, but for now use fork().

Problem reported and investigated by Ethan Solomita <ethan@geocast.com>.
Thanks.
2000-04-13 01:27:53 +00:00

348 lines
7.5 KiB
C

/* $NetBSD: ktrace.c,v 1.16 2000/04/13 01:27:53 itohy Exp $ */
/*-
* Copyright (c) 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1988, 1993\n\
The Regents of the University of California. All rights reserved.\n");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)ktrace.c 8.2 (Berkeley) 4/28/95";
#else
__RCSID("$NetBSD: ktrace.c,v 1.16 2000/04/13 01:27:53 itohy Exp $");
#endif
#endif /* not lint */
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/file.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <sys/ktrace.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "ktrace.h"
#ifdef KTRUSS
#include <string.h>
#include "setemul.h"
#endif
int main __P((int, char **));
int rpid __P((char *));
void usage __P((void));
int do_ktrace __P((char *, int, int,int));
void no_ktrace __P((int));
#ifdef KTRUSS
extern int timestamp, decimal, fancy, tail, maxdata;
#endif
int
main(argc, argv)
int argc;
char **argv;
{
enum { NOTSET, CLEAR, CLEARALL } clear;
int append, ch, fd, inherit, ops, pid, pidset, trpoints;
char *infile, *outfile;
#ifdef KTRUSS
const char *emul_name = "netbsd";
#endif
clear = NOTSET;
append = ops = pidset = inherit = 0;
trpoints = DEF_POINTS;
pid = 0; /* Appease GCC */
#ifdef KTRUSS
# define OPTIONS "aCce:df:g:ilm:o:p:RTt:"
outfile = infile = NULL;
#else
# define OPTIONS "aCcdf:g:ip:t:"
outfile = infile = DEF_TRACEFILE;
#endif
while ((ch = getopt(argc,argv, OPTIONS)) != -1)
switch((char)ch) {
case 'a':
append = 1;
break;
case 'C':
clear = CLEARALL;
pidset = 1;
break;
case 'c':
clear = CLEAR;
pidset = 1;
break;
case 'd':
ops |= KTRFLAG_DESCEND;
break;
#ifdef KTRUSS
case 'e':
emul_name = strdup(optarg); /* it's safer to copy it */
break;
case 'f':
infile = optarg;
break;
#else
case 'f':
infile = outfile = optarg;
break;
#endif
case 'g':
pid = -rpid(optarg);
pidset = 1;
break;
case 'i':
inherit = 1;
break;
#ifdef KTRUSS
case 'l':
tail = 1;
break;
case 'm':
maxdata = atoi(optarg);
break;
case 'o':
outfile = optarg;
break;
#endif
case 'p':
pid = rpid(optarg);
pidset = 1;
break;
#ifdef KTRUSS
case 'R':
timestamp = 2; /* relative timestamp */
break;
case 'T':
timestamp = 1;
break;
#endif
case 't':
trpoints = getpoints(optarg);
if (trpoints < 0) {
warnx("unknown facility in %s", optarg);
usage();
}
break;
default:
usage();
}
argv += optind;
argc -= optind;
if (!infile && ((pidset && *argv) || (!pidset && !*argv)))
usage();
#ifdef KTRUSS
if (infile) {
dumpfile(infile, 0, trpoints);
exit(0);
}
setemul(emul_name, 0, 0);
#endif
if (inherit)
trpoints |= KTRFAC_INHERIT;
(void)signal(SIGSYS, no_ktrace);
if (clear != NOTSET) {
if (clear == CLEARALL) {
ops = KTROP_CLEAR | KTRFLAG_DESCEND;
trpoints = ALL_POINTS;
pid = 1;
} else
ops |= pid ? KTROP_CLEAR : KTROP_CLEARFILE;
(void)do_ktrace(outfile, ops, trpoints, pid);
exit(0);
}
if (outfile && strcmp(outfile, "-")) {
if ((fd = open(outfile, O_CREAT | O_WRONLY |
(append ? 0 : O_TRUNC), DEFFILEMODE)) < 0)
err(1, outfile);
(void)close(fd);
}
if (*argv) {
#ifdef KTRUSS
if (do_ktrace(outfile, ops, trpoints, getpid()) == 1) {
execvp(argv[0], &argv[0]);
err(1, "exec of '%s' failed", argv[0]);
}
#else
(void) do_ktrace(outfile, ops, trpoints, getpid());
execvp(argv[0], &argv[0]);
err(1, "exec of '%s' failed", argv[0]);
#endif
} else
(void)do_ktrace(outfile, ops, trpoints, pid);
exit(0);
}
int
rpid(p)
char *p;
{
static int first;
if (first++) {
warnx("only one -g or -p flag is permitted.");
usage();
}
if (!*p) {
warnx("illegal process id.");
usage();
}
return(atoi(p));
}
void
usage()
{
extern char *__progname;
#ifdef KTRUSS
# define LONG_OPTION "[-e emulation] [-m maxdata] [-o outfile] "
# define SHRT_OPTION "RT"
#else
# define LONG_OPTION ""
# define SHRT_OPTION ""
#endif
(void)fprintf(stderr,
"Usage:\t%s [-aCcid%s] %s[-f trfile] [-g pgid] [-p pid] [-t [cenisw+]]\n\t%s [-aCcid%s] %s[-f trfile] [-t [cenisw+]] command\n",
__progname, SHRT_OPTION, LONG_OPTION,
__progname, SHRT_OPTION, LONG_OPTION);
exit(1);
}
void
no_ktrace(sig)
int sig;
{
(void)fprintf(stderr,
"error:\tktrace() system call not supported in the running kernel\n\tre-compile kernel with 'options KTRACE'\n");
exit(1);
}
int
do_ktrace(tracefile, ops, trpoints, pid)
char *tracefile;
int ops;
int trpoints;
int pid;
{
int ret;
if (!tracefile || strcmp(tracefile, "-") == 0) {
int pi[2], dofork, fpid;
if (pipe(pi) < 0)
err(1, "pipe(2)");
fcntl(pi[0], F_SETFD, FD_CLOEXEC|fcntl(pi[0], F_GETFD, 0));
fcntl(pi[1], F_SETFD, FD_CLOEXEC|fcntl(pi[1], F_GETFD, 0));
dofork = (pid == getpid());
#ifdef KTRUSS
if (dofork)
fpid = fork();
else
fpid = pid; /* XXX: Gcc */
#else
if (dofork)
fpid = fork();
else
fpid = 0; /* XXX: Gcc */
#endif
#ifdef KTRUSS
if (fpid)
#else
if (!dofork || !fpid)
#endif
{
if (!dofork)
#ifdef KTRUSS
ret = fktrace(pi[1], ops, trpoints, fpid);
#else
ret = fktrace(pi[1], ops, trpoints, pid);
#endif
else
close(pi[1]);
#ifdef KTRUSS
dumpfile(NULL, pi[0], trpoints);
waitpid(fpid, NULL, 0);
#else
{
char buf[512];
int n, cnt = 0;
while ((n = read(pi[0], buf, sizeof(buf)))>0) {
write(1, buf, n);
cnt += n;
}
}
if (dofork)
_exit(0);
#endif
return 0;
}
close(pi[0]);
#ifdef KTRUSS
if (dofork && !fpid) {
ret = fktrace(pi[1], ops, trpoints, getpid());
return 1;
}
#else
ret = fktrace(pi[1], ops, trpoints, pid);
#endif
} else
ret = ktrace(tracefile, ops, trpoints, pid);
if (ret < 0)
err(1, tracefile);
return 1;
}