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mirror of https://git.FreeBSD.org/src.git synced 2024-12-05 09:14:03 +00:00
freebsd/usr.bin/truss/main.c
Jaakko Heinonen ecbb6d348f Avoid sharing the file descriptor of the output file with traced
processes by setting the FD_CLOEXEC flag for the output file.

PR:		bin/140493
Submitted by:	Erik Lax
OK'ed by:	delphij
Approved by:	trasz (mentor)
2009-12-20 11:00:53 +00:00

387 lines
10 KiB
C

/*-
* Copryight 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. Suprisingly 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/param.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/sysctl.h>
#include <sys/wait.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include "truss.h"
#include "extern.h"
#include "syscall.h"
#define MAXARGS 6
static void
usage(void)
{
fprintf(stderr, "%s\n%s\n",
"usage: truss [-cfaedDS] [-o file] [-s strsize] -p pid",
" truss [-cfaedDS] [-o file] [-s strsize] command [args]");
exit(1);
}
/*
* WARNING! "FreeBSD a.out" must be first, or set_etype will not
* work correctly.
*/
struct ex_types {
const char *type;
void (*enter_syscall)(struct trussinfo *, int);
long (*exit_syscall)(struct trussinfo *, int);
} ex_types[] = {
#ifdef __amd64__
{ "FreeBSD ELF64", amd64_syscall_entry, amd64_syscall_exit },
{ "FreeBSD ELF32", amd64_fbsd32_syscall_entry, amd64_fbsd32_syscall_exit },
{ "Linux ELF32", amd64_linux32_syscall_entry, amd64_linux32_syscall_exit },
#endif
#ifdef __i386__
{ "FreeBSD a.out", i386_syscall_entry, i386_syscall_exit },
{ "FreeBSD ELF", i386_syscall_entry, i386_syscall_exit },
{ "FreeBSD ELF32", i386_syscall_entry, i386_syscall_exit },
{ "Linux ELF", i386_linux_syscall_entry, i386_linux_syscall_exit },
#endif
#ifdef __ia64__
{ "FreeBSD ELF64", ia64_syscall_entry, ia64_syscall_exit },
#endif
#ifdef __powerpc__
{ "FreeBSD ELF", powerpc_syscall_entry, powerpc_syscall_exit },
{ "FreeBSD ELF32", powerpc_syscall_entry, powerpc_syscall_exit },
#endif
#ifdef __sparc64__
{ "FreeBSD ELF64", sparc64_syscall_entry, sparc64_syscall_exit },
#endif
#ifdef __mips__
{ "FreeBSD ELF", mips_syscall_entry, mips_syscall_exit },
{ "FreeBSD ELF32", mips_syscall_entry, mips_syscall_exit },
{ "FreeBSD ELF64", mips_syscall_entry, mips_syscall_exit }, // XXX
#endif
{ 0, 0, 0 },
};
/*
* Set the execution type. This is called after every exec, and when
* a process is first monitored.
*/
static struct ex_types *
set_etype(struct trussinfo *trussinfo)
{
struct ex_types *funcs;
char progt[32];
size_t len = sizeof(progt);
int mib[4];
int error;
mib[0] = CTL_KERN;
mib[1] = KERN_PROC;
mib[2] = KERN_PROC_SV_NAME;
mib[3] = trussinfo->pid;
error = sysctl(mib, 4, progt, &len, NULL, 0);
if (error != 0)
err(2, "can not get etype");
for (funcs = ex_types; funcs->type; funcs++)
if (!strcmp(funcs->type, progt))
break;
if (funcs->type == NULL) {
funcs = &ex_types[0];
warn("execution type %s is not supported -- using %s",
progt, funcs->type);
}
return (funcs);
}
char *
strsig(int sig)
{
char *ret;
ret = NULL;
if (sig > 0 && sig < NSIG) {
int i;
asprintf(&ret, "sig%s", sys_signame[sig]);
if (ret == NULL)
return (NULL);
for (i = 0; ret[i] != '\0'; ++i)
ret[i] = toupper(ret[i]);
}
return (ret);
}
int
main(int ac, char **av)
{
int c;
int i;
pid_t childpid;
int status;
char **command;
struct ex_types *funcs;
int initial_open;
char *fname;
struct trussinfo *trussinfo;
char *signame;
fname = NULL;
initial_open = 1;
/* Initialize the trussinfo struct */
trussinfo = (struct trussinfo *)calloc(1, sizeof(struct trussinfo));
if (trussinfo == NULL)
errx(1, "calloc() failed");
trussinfo->outfile = stderr;
trussinfo->strsize = 32;
trussinfo->pr_why = S_NONE;
trussinfo->curthread = NULL;
SLIST_INIT(&trussinfo->threadlist);
while ((c = getopt(ac, av, "p:o:facedDs:S")) != -1) {
switch (c) {
case 'p': /* specified pid */
trussinfo->pid = atoi(optarg);
/* make sure i don't trace me */
if(trussinfo->pid == getpid()) {
fprintf(stderr, "attempt to grab self.\n");
exit(2);
}
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;
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 = atoi(optarg);
break;
case 'S': /* Don't trace signals */
trussinfo->flags |= NOSIGS;
break;
default:
usage();
}
}
ac -= optind; av += optind;
if ((trussinfo->pid == 0 && ac == 0) ||
(trussinfo->pid != 0 && ac != 0))
usage();
if (fname != NULL) { /* Use output file */
if ((trussinfo->outfile = fopen(fname, "w")) == NULL)
errx(1, "cannot open %s", fname);
}
/*
* Set FD_CLOEXEC, so that the output file is not shared with
* the traced process.
*/
if (fcntl(fileno(trussinfo->outfile), F_SETFD, FD_CLOEXEC) == -1)
warn("fcntl()");
/*
* 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 (trussinfo->pid == 0) { /* Start a command ourselves */
command = av;
trussinfo->pid = setup_and_wait(command);
signal(SIGINT, SIG_IGN);
signal(SIGTERM, SIG_IGN);
signal(SIGQUIT, SIG_IGN);
} else {
start_tracing(trussinfo->pid);
signal(SIGINT, restore_proc);
signal(SIGTERM, restore_proc);
signal(SIGQUIT, restore_proc);
}
/*
* At this point, if we started the process, it is stopped waiting to
* be woken up, either in exit() or in execve().
*/
START_TRACE:
funcs = set_etype(trussinfo);
initial_open = 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);
do {
struct timespec timediff;
waitevent(trussinfo);
switch(i = trussinfo->pr_why) {
case S_SCE:
funcs->enter_syscall(trussinfo, MAXARGS);
clock_gettime(CLOCK_REALTIME,
&trussinfo->before);
break;
case S_SCX:
clock_gettime(CLOCK_REALTIME,
&trussinfo->after);
if (trussinfo->curthread->in_fork &&
(trussinfo->flags & FOLLOWFORKS)) {
trussinfo->curthread->in_fork = 0;
childpid =
funcs->exit_syscall(trussinfo,
trussinfo->pr_data);
/*
* Fork a new copy of ourself to trace
* the child of the original traced
* process.
*/
if (fork() == 0) {
trussinfo->pid = childpid;
start_tracing(trussinfo->pid);
goto START_TRACE;
}
break;
}
funcs->exit_syscall(trussinfo, MAXARGS);
break;
case S_SIG:
if (trussinfo->flags & NOSIGS)
break;
if (trussinfo->flags & FOLLOWFORKS)
fprintf(trussinfo->outfile, "%5d: ",
trussinfo->pid);
if (trussinfo->flags & ABSOLUTETIMESTAMPS) {
timespecsubt(&trussinfo->after,
&trussinfo->start_time, &timediff);
fprintf(trussinfo->outfile, "%ld.%09ld ",
(long)timediff.tv_sec,
timediff.tv_nsec);
}
if (trussinfo->flags & RELATIVETIMESTAMPS) {
timespecsubt(&trussinfo->after,
&trussinfo->before, &timediff);
fprintf(trussinfo->outfile, "%ld.%09ld ",
(long)timediff.tv_sec,
timediff.tv_nsec);
}
signame = strsig(trussinfo->pr_data);
fprintf(trussinfo->outfile,
"SIGNAL %u (%s)\n", trussinfo->pr_data,
signame == NULL ? "?" : signame);
free(signame);
break;
case S_EXIT:
if (trussinfo->flags & COUNTONLY)
break;
if (trussinfo->flags & FOLLOWFORKS)
fprintf(trussinfo->outfile, "%5d: ",
trussinfo->pid);
if (trussinfo->flags & ABSOLUTETIMESTAMPS) {
timespecsubt(&trussinfo->after,
&trussinfo->start_time, &timediff);
fprintf(trussinfo->outfile, "%ld.%09ld ",
(long)timediff.tv_sec,
timediff.tv_nsec);
}
if (trussinfo->flags & RELATIVETIMESTAMPS) {
timespecsubt(&trussinfo->after,
&trussinfo->before, &timediff);
fprintf(trussinfo->outfile, "%ld.%09ld ",
(long)timediff.tv_sec, timediff.tv_nsec);
}
fprintf(trussinfo->outfile,
"process exit, rval = %u\n", trussinfo->pr_data);
break;
default:
break;
}
} while (trussinfo->pr_why != S_EXIT);
if (trussinfo->flags & FOLLOWFORKS)
do {
childpid = wait(&status);
} while (childpid != -1);
if (trussinfo->flags & COUNTONLY)
print_summary(trussinfo);
fflush(trussinfo->outfile);
return (0);
}