* Copyright (c) 1988, 1993

/* $NetBSD: ktrace.c,v 1.46 2013/01/24 17:47:58 christos 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\
The Regents of the University of California. All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)ktrace.c 8.2 (Berkeley) 4/28/95";
#else
__RCSID("$NetBSD: ktrace.c,v 1.46 2013/01/24 17:47:58 christos 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 <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>

#include "ktrace.h"

#ifdef KTRUSS
#include "setemul.h"
#endif

static int rpid(char *);
__dead static void usage(void);
static int do_ktrace(const char *, int, int, int, int, int);
__dead static void no_ktrace(int);
static void fclear(int fd, int flag);

#ifdef KTRUSS
extern int timestamp, decimal, fancy, tail, maxdata;
#endif

int
main(int argc, char *argv[])
{
enum { NOTSET, CLEAR, CLEARALL } clear;
int block, append, ch, fd, trset, ops, pid, pidset, synclog, trpoints;
int vers;
const char *outfile;
#ifdef KTRUSS
const char *infile;
const char *emul_name = "netbsd";
#endif

clear = NOTSET;
append = ops = pidset = trset = synclog = 0;
trpoints = 0;
block = 1;
vers = 2;
pid = 0; /* Appease GCC */

#ifdef KTRUSS
# define OPTIONS "aCce:df:g:ilm:no:p:RTt:v:"
outfile = infile = NULL;
#else
# define OPTIONS "aCcdf:g:ip:st:v:"
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 'n':
block = 0;
break;
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;
case 'v':
vers = atoi(optarg);
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, vers, ops, trpoints, pid, block);
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(EXIT_FAILURE, "%s", outfile);
(void)close(fd);
}

if (*argv) {
#ifdef KTRUSS
if (do_ktrace(outfile, vers, ops, trpoints, getpid(), block) == 1) {
execvp(argv[0], &argv[0]);
err(EXIT_FAILURE, "exec of '%s' failed", argv[0]);
}
#else
(void)do_ktrace(outfile, vers, ops, trpoints, getpid(), block);
execvp(argv[0], &argv[0]);
err(EXIT_FAILURE, "exec of '%s' failed", argv[0]);
#endif
} else
(void)do_ktrace(outfile, vers, ops, trpoints, pid, block);
return 0;
}

static int
rpid(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));
}

static void
fclear(int fd, int flag)
{
int oflag = fcntl(fd, F_GETFL, 0);

if (oflag == -1)
err(EXIT_FAILURE, "Cannot get file flags");
if (fcntl(fd, F_SETFL, oflag & ~flag) == -1)
err(EXIT_FAILURE, "Cannot set file flags");
}

static void
usage(void)
{

#define TRPOINTS "[AaceilmnSsuvw+-]"
#ifdef KTRUSS
(void)fprintf(stderr, "usage:\t%s "
"[-aCcdilnRT] [-e emulation] [-f infile] [-g pgrp] "
"[-m maxdata]\n\t "
"[-o outfile] [-p pid] [-t " TRPOINTS "]\n", getprogname());
(void)fprintf(stderr, "\t%s "
"[-adinRT] [-e emulation] [-m maxdata] [-o outfile]\n\t "
"[-t " TRPOINTS "] [-v vers] command\n",
getprogname());
#else
(void)fprintf(stderr, "usage:\t%s "
"[-aCcdins] [-f trfile] [-g pgrp] [-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;
static void
/*ARGSUSED*/
no_ktrace(int sig)
{

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

static int
do_ktrace(const char *tracefile, int vers, int ops, int trpoints, int pid,
int block)
{
int ret;
ops |= vers << KTRFAC_VER_SHIFT;

if (KTROP(ops) == KTROP_SET &&
(!tracefile || strcmp(tracefile, "-") == 0)) {
int pi[2], dofork;

if (pipe2(pi, O_CLOEXEC) == -1)
err(EXIT_FAILURE, "pipe(2)");

dofork = (pid == getpid());

if (dofork) {
#ifdef KTRUSS
/*
* Create a child process and trace it.
*/
pid = fork();
if (pid == -1)
err(EXIT_FAILURE, "fork");
else if (pid == 0) {
pid = getpid();
goto trace_and_exec;
}
#else
int fpid;

/*
* Create a dumper process and we will be
* traced.
*/
fpid = fork();
if (fpid == -1)
err(EXIT_FAILURE, "fork");
else if (fpid != 0)
goto trace_and_exec;
#endif
(void)close(pi[1]);
} else {
ret = fktrace(pi[1], ops, trpoints, pid);
if (ret == -1)
err(EXIT_FAILURE, "fd %d, pid %d",
pi[1], pid);
if (block)
fclear(pi[1], O_NONBLOCK);
}
#ifdef KTRUSS
dumpfile(NULL, pi[0], trpoints);
waitpid(pid, NULL, 0);
#else
{
char buf[BUFSIZ];
int n;

while ((n =
read(pi[0], buf, sizeof(buf))) > 0)
if (write(STDOUT_FILENO, buf, (size_t)n) == -1)
warn("write failed");
}
if (dofork)
_exit(0);
#endif
return 0;

trace_and_exec:
(void)close(pi[0]);
ret = fktrace(pi[1], ops, trpoints, pid);
if (ret == -1)
err(EXIT_FAILURE, "fd %d, pid %d", pi[1], pid);
if (block)
fclear(pi[1], O_NONBLOCK);
} 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;
}