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/*-
* SPDX-License-Identifier: BSD-4-Clause
*
* Copyright 1997 Sean Eric Fagan
*
* 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 Sean Eric Fagan
* 4. Neither the name of the author may be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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>
__FBSDID("$FreeBSD$");
/*
* The main module for truss. Surprisingly simple, but, then, the other
* files handle the bulk of the work. And, of course, the kernel has to
* do a lot of the work :).
*/
#include <sys/ptrace.h>
#include <err.h>
#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <sysdecode.h>
#include <time.h>
#include <unistd.h>
#include "truss.h"
#include "extern.h"
#include "syscall.h"
static void
usage(void)
{
fprintf(stderr, "%s\n%s\n",
"usage: truss [-cfaedDHS] [-o file] [-s strsize] -p pid",
" truss [-cfaedDHS] [-o file] [-s strsize] command [args]");
exit(1);
}
int
main(int ac, char **av)
{
struct sigaction sa;
struct trussinfo *trussinfo;
char *fname;
char **command;
const char *errstr;
pid_t pid;
int c;
fname = NULL;
/* Initialize the trussinfo struct */
trussinfo = (struct trussinfo *)calloc(1, sizeof(struct trussinfo));
if (trussinfo == NULL)
errx(1, "calloc() failed");
pid = 0;
trussinfo->outfile = stderr;
trussinfo->strsize = 32;
trussinfo->curthread = NULL;
LIST_INIT(&trussinfo->proclist);
init_syscalls();
while ((c = getopt(ac, av, "p:o:facedDs:SH")) != -1) {
switch (c) {
case 'p': /* specified pid */
pid = atoi(optarg);
/* make sure i don't trace me */
if (pid == getpid()) {
errx(2, "attempt to grab self.");
}
break;
case 'f': /* Follow fork()'s */
trussinfo->flags |= FOLLOWFORKS;
break;
case 'a': /* Print execve() argument strings. */
trussinfo->flags |= EXECVEARGS;
break;
case 'c': /* Count number of system calls and time. */
trussinfo->flags |= (COUNTONLY | NOSIGS);
break;
case 'e': /* Print execve() environment strings. */
trussinfo->flags |= EXECVEENVS;
break;
case 'd': /* Absolute timestamps */
trussinfo->flags |= ABSOLUTETIMESTAMPS;
break;
case 'D': /* Relative timestamps */
trussinfo->flags |= RELATIVETIMESTAMPS;
break;
case 'o': /* Specified output file */
fname = optarg;
break;
case 's': /* Specified string size */
trussinfo->strsize = strtonum(optarg, 0, INT_MAX, &errstr);
if (errstr)
errx(1, "maximum string size is %s: %s", errstr, optarg);
break;
case 'S': /* Don't trace signals */
trussinfo->flags |= NOSIGS;
break;
case 'H':
trussinfo->flags |= DISPLAYTIDS;
break;
default:
usage();
}
}
ac -= optind; av += optind;
if ((pid == 0 && ac == 0) ||
(pid != 0 && ac != 0))
usage();
if (fname != NULL) { /* Use output file */
/*
* Set close-on-exec ('e'), so that the output file is not
* shared with the traced process.
*/
if ((trussinfo->outfile = fopen(fname, "we")) == NULL)
err(1, "cannot open %s", fname);
}
/*
* If truss starts the process itself, it will ignore some signals --
* they should be passed off to the process, which may or may not
* exit. If, however, we are examining an already-running process,
* then we restore the event mask on these same signals.
*/
if (pid == 0) {
/* Start a command ourselves */
command = av;
setup_and_wait(trussinfo, command);
signal(SIGINT, SIG_IGN);
signal(SIGTERM, SIG_IGN);
signal(SIGQUIT, SIG_IGN);
} else {
sa.sa_handler = restore_proc;
sa.sa_flags = 0;
sigemptyset(&sa.sa_mask);
sigaction(SIGINT, &sa, NULL);
sigaction(SIGQUIT, &sa, NULL);
sigaction(SIGTERM, &sa, NULL);
start_tracing(trussinfo, pid);
}
/*
* At this point, if we started the process, it is stopped waiting to
* be woken up, either in exit() or in execve().
*/
if (LIST_FIRST(&trussinfo->proclist)->abi == NULL) {
/*
* If we are not able to handle this ABI, detach from the
* process and exit. If we just created a new process to
* run a command, kill the new process rather than letting
* it run untraced.
*/
if (pid == 0)
kill(LIST_FIRST(&trussinfo->proclist)->pid, SIGKILL);
ptrace(PT_DETACH, LIST_FIRST(&trussinfo->proclist)->pid, NULL,
0);
return (1);
}
ptrace(PT_SYSCALL, LIST_FIRST(&trussinfo->proclist)->pid, (caddr_t)1,
0);
/*
* At this point, it's a simple loop, waiting for the process to
* stop, finding out why, printing out why, and then continuing it.
* All of the grunt work is done in the support routines.
*/
clock_gettime(CLOCK_REALTIME, &trussinfo->start_time);
eventloop(trussinfo);
if (trussinfo->flags & COUNTONLY)
print_summary(trussinfo);
fflush(trussinfo->outfile);
return (0);
}
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