xref: /src/usr.bin/ktrace/ktrace.c

/*	$NetBSD: ktrace.c,v 1.33 2004/02/28 02:22:31 enami 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. 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 1.33 2004/02/28 02:22:31 enami 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 <sys/socket.h>

#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.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((const 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, trset, ops, pid, pidset, synclog, trpoints;
	const char *outfile;
#ifdef KTRUSS
	const char *infile;
	const char *emul_name = "netbsd";
#endif

	clear = NOTSET;
	append = ops = pidset = trset = synclog = 0;
	trpoints = 0;
	pid = 0;	/* Appease GCC */

#ifdef KTRUSS
# define OPTIONS "aCce:df:g:ilm:o:p:RTt:"
	outfile = infile = NULL;
#else
# define OPTIONS "aCcdf:g:ip:st:"
	outfile = DEF_TRACEFILE;
#endif

	while ((ch = getopt(argc, argv, OPTIONS)) != -1)
		switch (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':
			outfile = optarg;
			break;
#endif
		case 'g':
			pid = -rpid(optarg);
			pidset = 1;
			break;
		case 'i':
			trpoints |= KTRFAC_INHERIT;
			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;
#else
		case 's':
			synclog = 1;
			break;
#endif
#ifdef KTRUSS
		case 'T':
			timestamp = 1;
			break;
#endif
		case 't':
			trset = 1;
			trpoints = getpoints(trpoints, optarg);
			if (trpoints < 0) {
				warnx("unknown facility in %s", optarg);
				usage();
			}
			break;
		default:
			usage();
		}
	argv += optind;
	argc -= optind;

	if (!trset)
		trpoints |= clear == NOTSET ? DEF_POINTS : ALL_POINTS;

	if ((pidset && *argv) || (!pidset && !*argv)) {
#ifdef KTRUSS
		if (!infile)
#endif
			usage();
	}

#ifdef KTRUSS
	if (clear == CLEAR && outfile == NULL && pid == 0)
		usage();

	if (infile) {
		dumpfile(infile, 0, trpoints);
		exit(0);
	}

	setemul(emul_name, 0, 0);
#endif

	/*
	 * For cleaner traces, initialize malloc now rather
	 * than in a traced subprocess.
	 */
	free(malloc(1));

	(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) | (synclog ? 0 : O_SYNC),
		    DEFFILEMODE)) < 0)
			err(1, "%s", 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()
{

#define	TRPOINTS "[Aaceilmnsuvw+-]"
#ifdef KTRUSS
	(void)fprintf(stderr, "usage:\t%s "
	    "[-aCcdilRT] [-e emulation] [-f infile] [-g pgid] "
	    "[-m maxdata]\n\t    "
	    "[-o outfile] [-p pid] [-t " TRPOINTS "]\n", getprogname());
	(void)fprintf(stderr, "\t%s "
	    "[-adiRT] [-e emulation] [-m maxdata] [-o outfile]\n\t    "
	    "[-t " TRPOINTS "] command\n",
	    getprogname());
#else
	(void)fprintf(stderr, "usage:\t%s "
	    "[-aCcdis] [-f trfile] [-g pgid] [-p pid] [-t " TRPOINTS "]\n",
	    getprogname());
	(void)fprintf(stderr, "\t%s "
	    "[-adis] [-f trfile] [-t " TRPOINTS "] command\n",
	    getprogname());
#endif
	exit(1);
}

static const char *ktracefile = NULL;
void
no_ktrace(sig)
	int sig;
{

	if (ktracefile)
		(void)unlink(ktracefile);
	(void)errx(1, "ktrace(2) system call not supported in the running"
	    " kernel; re-compile kernel with `options KTRACE'");
}

int
do_ktrace(tracefile, ops, trpoints, pid)
	const char *tracefile;
	int ops;
	int trpoints;
	int pid;
{
	int ret;

	if (KTROP(ops) == KTROP_SET &&
	    (!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
		if (ret == -1)
			err(EXIT_FAILURE, "fd %d, pid %d", pi[1], pid);
	} else {
		ret = ktrace(ktracefile = tracefile, ops, trpoints, pid);
		if (ret == -1)
			err(EXIT_FAILURE, "file %s, pid %d",
			    tracefile != NULL ? tracefile : "NULL", pid);
	}
	return 1;
}