strace/desc.c
Roland McGrath fe10aa70a7 2007-09-22 Dmitry V. Levin <ldv@altlinux.org>
* desc.c (sys_pselect6): Decode signal mask when entering syscall.
	Relax signal mask size check.
2007-11-01 21:52:20 +00:00

899 lines
17 KiB
C

/*
* Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
* Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
* Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
* Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*
* $Id$
*/
#include "defs.h"
#include <fcntl.h>
#include <sys/file.h>
#ifdef LINUX
#include <inttypes.h>
#endif
#ifdef HAVE_SYS_EPOLL_H
#include <sys/epoll.h>
#endif
#ifdef HAVE_LIBAIO_H
#include <libaio.h>
#endif
#if HAVE_LONG_LONG_OFF_T
/*
* Hacks for systems that have a long long off_t
*/
#define flock64 flock /* Horrid hack */
#define printflock printflock64 /* Horrider hack */
#endif
static const struct xlat fcntlcmds[] = {
{ F_DUPFD, "F_DUPFD" },
{ F_GETFD, "F_GETFD" },
{ F_SETFD, "F_SETFD" },
{ F_GETFL, "F_GETFL" },
{ F_SETFL, "F_SETFL" },
{ F_GETLK, "F_GETLK" },
{ F_SETLK, "F_SETLK" },
{ F_SETLKW, "F_SETLKW" },
{ F_GETOWN, "F_GETOWN" },
{ F_SETOWN, "F_SETOWN" },
#ifdef F_RSETLK
{ F_RSETLK, "F_RSETLK" },
#endif
#ifdef F_RSETLKW
{ F_RSETLKW, "F_RSETLKW" },
#endif
#ifdef F_RGETLK
{ F_RGETLK, "F_RGETLK" },
#endif
#ifdef F_CNVT
{ F_CNVT, "F_CNVT" },
#endif
#ifdef F_SETSIG
{ F_SETSIG, "F_SETSIG" },
#endif
#ifdef F_GETSIG
{ F_GETSIG, "F_GETSIG" },
#endif
#ifdef F_CHKFL
{ F_CHKFL, "F_CHKFL" },
#endif
#ifdef F_DUP2FD
{ F_DUP2FD, "F_DUP2FD" },
#endif
#ifdef F_ALLOCSP
{ F_ALLOCSP, "F_ALLOCSP" },
#endif
#ifdef F_ISSTREAM
{ F_ISSTREAM, "F_ISSTREAM" },
#endif
#ifdef F_PRIV
{ F_PRIV, "F_PRIV" },
#endif
#ifdef F_NPRIV
{ F_NPRIV, "F_NPRIV" },
#endif
#ifdef F_QUOTACL
{ F_QUOTACL, "F_QUOTACL" },
#endif
#ifdef F_BLOCKS
{ F_BLOCKS, "F_BLOCKS" },
#endif
#ifdef F_BLKSIZE
{ F_BLKSIZE, "F_BLKSIZE" },
#endif
#ifdef F_GETOWN
{ F_GETOWN, "F_GETOWN" },
#endif
#ifdef F_SETOWN
{ F_SETOWN, "F_SETOWN" },
#endif
#ifdef F_REVOKE
{ F_REVOKE, "F_REVOKE" },
#endif
#ifdef F_SETLK
{ F_SETLK, "F_SETLK" },
#endif
#ifdef F_SETLKW
{ F_SETLKW, "F_SETLKW" },
#endif
#ifdef F_FREESP
{ F_FREESP, "F_FREESP" },
#endif
#ifdef F_GETLK
{ F_GETLK, "F_GETLK" },
#endif
#ifdef F_SETLK64
{ F_SETLK64, "F_SETLK64" },
#endif
#ifdef F_SETLKW64
{ F_SETLKW64, "F_SETLKW64" },
#endif
#ifdef F_FREESP64
{ F_FREESP64, "F_FREESP64" },
#endif
#ifdef F_GETLK64
{ F_GETLK64, "F_GETLK64" },
#endif
#ifdef F_SHARE
{ F_SHARE, "F_SHARE" },
#endif
#ifdef F_UNSHARE
{ F_UNSHARE, "F_UNSHARE" },
#endif
{ 0, NULL },
};
static const struct xlat fdflags[] = {
#ifdef FD_CLOEXEC
{ FD_CLOEXEC, "FD_CLOEXEC" },
#endif
{ 0, NULL },
};
#ifdef LOCK_SH
static const struct xlat flockcmds[] = {
{ LOCK_SH, "LOCK_SH" },
{ LOCK_EX, "LOCK_EX" },
{ LOCK_NB, "LOCK_NB" },
{ LOCK_UN, "LOCK_UN" },
{ 0, NULL },
};
#endif /* LOCK_SH */
static const struct xlat lockfcmds[] = {
{ F_RDLCK, "F_RDLCK" },
{ F_WRLCK, "F_WRLCK" },
{ F_UNLCK, "F_UNLCK" },
#ifdef F_EXLCK
{ F_EXLCK, "F_EXLCK" },
#endif
#ifdef F_SHLCK
{ F_SHLCK, "F_SHLCK" },
#endif
{ 0, NULL },
};
static const struct xlat whence[] = {
{ SEEK_SET, "SEEK_SET" },
{ SEEK_CUR, "SEEK_CUR" },
{ SEEK_END, "SEEK_END" },
{ 0, NULL },
};
#ifndef HAVE_LONG_LONG_OFF_T
/* fcntl/lockf */
static void
printflock(tcp, addr, getlk)
struct tcb *tcp;
long addr;
int getlk;
{
struct flock fl;
if (umove(tcp, addr, &fl) < 0) {
tprintf("{...}");
return;
}
tprintf("{type=");
printxval(lockfcmds, fl.l_type, "F_???");
tprintf(", whence=");
printxval(whence, fl.l_whence, "SEEK_???");
tprintf(", start=%ld, len=%ld", fl.l_start, fl.l_len);
if (getlk)
tprintf(", pid=%lu}", (unsigned long) fl.l_pid);
else
tprintf("}");
}
#endif
#if _LFS64_LARGEFILE || HAVE_LONG_LONG_OFF_T
/* fcntl/lockf */
static void
printflock64(tcp, addr, getlk)
struct tcb *tcp;
long addr;
int getlk;
{
struct flock64 fl;
if (umove(tcp, addr, &fl) < 0) {
tprintf("{...}");
return;
}
tprintf("{type=");
printxval(lockfcmds, fl.l_type, "F_???");
tprintf(", whence=");
printxval(whence, fl.l_whence, "SEEK_???");
tprintf(", start=%lld, len=%lld", (long long) fl.l_start, (long long) fl.l_len);
if (getlk)
tprintf(", pid=%lu}", (unsigned long) fl.l_pid);
else
tprintf("}");
}
#endif
/*
* low bits of the open(2) flags define access mode,
* other bits are real flags.
*/
static const char *
sprint_open_modes(mode_t flags)
{
extern const struct xlat open_access_modes[];
extern const struct xlat open_mode_flags[];
static char outstr[1024];
const char *str = xlookup(open_access_modes, flags & 3);
const char *sep = "";
const struct xlat *x;
strcpy(outstr, "flags ");
if (str)
{
strcat(outstr, str);
flags &= ~3;
if (!flags)
return outstr;
strcat(outstr, "|");
}
for (x = open_mode_flags; x->str; x++)
{
if ((flags & x->val) == x->val)
{
sprintf(outstr + strlen(outstr),
"%s%s", sep, x->str);
sep = "|";
flags &= ~x->val;
}
}
if (flags)
sprintf(outstr + strlen(outstr), "%s%#x", sep, flags);
return outstr;
}
int
sys_fcntl(struct tcb *tcp)
{
if (entering(tcp)) {
tprintf("%ld, ", tcp->u_arg[0]);
printxval(fcntlcmds, tcp->u_arg[1], "F_???");
switch (tcp->u_arg[1]) {
case F_SETFD:
tprintf(", ");
printflags(fdflags, tcp->u_arg[2], "FD_???");
break;
case F_SETOWN: case F_DUPFD:
tprintf(", %ld", tcp->u_arg[2]);
break;
case F_SETFL:
tprintf(", ");
tprint_open_modes(tcp, tcp->u_arg[2]);
break;
case F_SETLK: case F_SETLKW:
#ifdef F_FREESP
case F_FREESP:
#endif
tprintf(", ");
printflock(tcp, tcp->u_arg[2], 0);
break;
#if _LFS64_LARGEFILE
#ifdef F_FREESP64
case F_FREESP64:
#endif
/* Linux glibc defines SETLK64 as SETLK,
even though the kernel has different values - as does Solaris. */
#if defined(F_SETLK64) && F_SETLK64+0!=F_SETLK
case F_SETLK64:
#endif
#if defined(F_SETLKW64) && F_SETLKW64+0!=F_SETLKW
case F_SETLKW64:
#endif
tprintf(", ");
printflock64(tcp, tcp->u_arg[2], 0);
break;
#endif
}
}
else {
switch (tcp->u_arg[1]) {
case F_DUPFD:
case F_SETFD: case F_SETFL:
case F_SETLK: case F_SETLKW:
case F_SETOWN: case F_GETOWN:
break;
case F_GETFD:
if (tcp->u_rval == 0)
return 0;
tcp->auxstr =
sprintflags("flags ", fdflags, tcp->u_rval);
return RVAL_HEX|RVAL_STR;
case F_GETFL:
tcp->auxstr = sprint_open_modes(tcp->u_rval);
return RVAL_HEX|RVAL_STR;
case F_GETLK:
tprintf(", ");
printflock(tcp, tcp->u_arg[2], 1);
break;
#if _LFS64_LARGEFILE
#if defined(F_GETLK64) && F_GETLK64+0!=F_GETLK
case F_GETLK64:
#endif
tprintf(", ");
printflock64(tcp, tcp->u_arg[2], 1);
break;
#endif
default:
tprintf(", %#lx", tcp->u_arg[2]);
break;
}
}
return 0;
}
#ifdef LOCK_SH
int
sys_flock(tcp)
struct tcb *tcp;
{
if (entering(tcp)) {
tprintf("%ld, ", tcp->u_arg[0]);
printflags(flockcmds, tcp->u_arg[1], "LOCK_???");
}
return 0;
}
#endif /* LOCK_SH */
int
sys_close(tcp)
struct tcb *tcp;
{
if (entering(tcp)) {
tprintf("%ld", tcp->u_arg[0]);
}
return 0;
}
int
sys_dup(tcp)
struct tcb *tcp;
{
if (entering(tcp)) {
tprintf("%ld", tcp->u_arg[0]);
}
return 0;
}
int
sys_dup2(tcp)
struct tcb *tcp;
{
if (entering(tcp)) {
tprintf("%ld, %ld", tcp->u_arg[0], tcp->u_arg[1]);
}
return 0;
}
#if defined(ALPHA) || defined(FREEBSD) || defined(SUNOS4)
int
sys_getdtablesize(tcp)
struct tcb *tcp;
{
return 0;
}
#endif /* ALPHA || FREEBSD || SUNOS4 */
static int
decode_select(struct tcb *tcp, long *args, enum bitness_t bitness)
{
int i, j, nfds;
unsigned int fdsize = ((((args[0] + 7) / 8) + sizeof(long) - 1)
& -sizeof(long));
fd_set *fds;
static char outstr[1024];
char *sep;
long arg;
if (entering(tcp)) {
fds = (fd_set *) malloc(fdsize);
if (fds == NULL)
fprintf(stderr, "out of memory\n");
nfds = args[0];
tprintf("%d", nfds);
for (i = 0; i < 3; i++) {
arg = args[i+1];
if (arg == 0) {
tprintf(", NULL");
continue;
}
if (fds == NULL || !verbose(tcp)) {
tprintf(", %#lx", arg);
continue;
}
if (umoven(tcp, arg, fdsize, (char *) fds) < 0) {
tprintf(", [?]");
continue;
}
tprintf(", [");
for (j = 0, sep = ""; j < nfds; j++) {
if (FD_ISSET(j, fds)) {
tprintf("%s%u", sep, j);
sep = " ";
}
}
tprintf("]");
}
free(fds);
tprintf(", ");
printtv_bitness(tcp, args[4], bitness, 0);
}
else
{
unsigned int cumlen = 0;
char *sep = "";
if (syserror(tcp))
return 0;
if ((nfds = tcp->u_rval) == 0) {
tcp->auxstr = "Timeout";
return RVAL_STR;
}
fds = (fd_set *) malloc(fdsize);
if (fds == NULL)
fprintf(stderr, "out of memory\n");
outstr[0] = '\0';
for (i = 0; i < 3; i++) {
int first = 1;
char str[20];
tcp->auxstr = outstr;
arg = args[i+1];
if (fds == NULL || !arg ||
umoven(tcp, arg, fdsize, (char *) fds) < 0)
continue;
for (j = 0; j < args[0]; j++) {
if (FD_ISSET(j, fds)) {
if (first) {
sprintf(str, "%s%s [%u", sep,
i == 0 ? "in" :
i == 1 ? "out" :
"except", j);
first = 0;
sep = ", ";
}
else
sprintf(str, " %u", j);
cumlen += strlen(str);
if (cumlen < sizeof(outstr))
strcat(outstr, str);
nfds--;
}
}
if (cumlen)
strcat(outstr, "]");
if (nfds == 0)
break;
}
free(fds);
#ifdef LINUX
/* This contains no useful information on SunOS. */
if (args[4]) {
char str[128];
sprintf(str, "%sleft ", sep);
sprinttv(tcp, args[4], bitness, str + strlen(str));
if ((cumlen += strlen(str)) < sizeof(outstr))
strcat(outstr, str);
}
#endif /* LINUX */
return RVAL_STR;
}
return 0;
}
#ifdef LINUX
int
sys_oldselect(tcp)
struct tcb *tcp;
{
long args[5];
if (umoven(tcp, tcp->u_arg[0], sizeof args, (char *) args) < 0) {
tprintf("[...]");
return 0;
}
return decode_select(tcp, args, BITNESS_CURRENT);
}
#ifdef ALPHA
int
sys_osf_select(tcp)
struct tcb *tcp;
{
long *args = tcp->u_arg;
return decode_select(tcp, args, BITNESS_32);
}
#endif
static struct xlat epollctls[] = {
#ifdef EPOLL_CTL_ADD
{ EPOLL_CTL_ADD, "EPOLL_CTL_ADD" },
#endif
#ifdef EPOLL_CTL_MOD
{ EPOLL_CTL_MOD, "EPOLL_CTL_MOD" },
#endif
#ifdef EPOLL_CTL_DEL
{ EPOLL_CTL_DEL, "EPOLL_CTL_DEL" },
#endif
{ 0, NULL }
};
static struct xlat epollevents[] = {
#ifdef EPOLLIN
{ EPOLLIN, "EPOLLIN" },
#endif
#ifdef EPOLLPRI
{ EPOLLPRI, "EPOLLPRI" },
#endif
#ifdef EPOLLOUT
{ EPOLLOUT, "EPOLLOUT" },
#endif
#ifdef EPOLLRDNORM
{ EPOLLRDNORM, "EPOLLRDNORM" },
#endif
#ifdef EPOLLRDBAND
{ EPOLLRDBAND, "EPOLLRDBAND" },
#endif
#ifdef EPOLLWRNORM
{ EPOLLWRNORM, "EPOLLWRNORM" },
#endif
#ifdef EPOLLWRBAND
{ EPOLLWRBAND, "EPOLLWRBAND" },
#endif
#ifdef EPOLLMSG
{ EPOLLMSG, "EPOLLMSG" },
#endif
#ifdef EPOLLERR
{ EPOLLERR, "EPOLLERR" },
#endif
#ifdef EPOLLHUP
{ EPOLLHUP, "EPOLLHUP" },
#endif
#ifdef EPOLLONESHOT
{ EPOLLONESHOT, "EPOLLONESHOT" },
#endif
#ifdef EPOLLET
{ EPOLLET, "EPOLLET" },
#endif
{ 0, NULL }
};
int
sys_epoll_create(tcp)
struct tcb *tcp;
{
if (entering(tcp))
tprintf("%ld", tcp->u_arg[0]);
return 0;
}
#ifdef HAVE_SYS_EPOLL_H
static void
print_epoll_event(ev)
struct epoll_event *ev;
{
tprintf("{");
printflags(epollevents, ev->events, "EPOLL???");
/* We cannot know what format the program uses, so print u32 and u64
which will cover every value. */
tprintf(", {u32=%" PRIu32 ", u64=%" PRIu64 "}}",
ev->data.u32, ev->data.u64);
}
#endif
int
sys_epoll_ctl(tcp)
struct tcb *tcp;
{
if (entering(tcp)) {
tprintf("%ld, ", tcp->u_arg[0]);
printxval(epollctls, tcp->u_arg[1], "EPOLL_CTL_???");
tprintf(", %ld, ", tcp->u_arg[2]);
if (tcp->u_arg[3] == 0)
tprintf("NULL");
else {
#ifdef HAVE_SYS_EPOLL_H
struct epoll_event ev;
if (umove(tcp, tcp->u_arg[3], &ev) == 0)
print_epoll_event(&ev);
else
#endif
tprintf("{...}");
}
}
return 0;
}
static void
epoll_wait_common(tcp)
struct tcb *tcp;
{
if (entering(tcp))
tprintf("%ld, ", tcp->u_arg[0]);
else {
if (syserror(tcp))
tprintf("%lx", tcp->u_arg[1]);
else if (tcp->u_rval == 0)
tprintf("{}");
else {
#ifdef HAVE_SYS_EPOLL_H
struct epoll_event ev, *start, *cur, *end;
int failed = 0;
tprintf("{");
start = (struct epoll_event *) tcp->u_arg[1];
end = start + tcp->u_rval;
for (cur = start; cur < end; ++cur) {
if (cur > start)
tprintf(", ");
if (umove(tcp, (long) cur, &ev) == 0)
print_epoll_event(&ev);
else {
tprintf("?");
failed = 1;
break;
}
}
tprintf("}");
if (failed)
tprintf(" %#lx", (long) start);
#else
tprintf("{...}");
#endif
}
tprintf(", %ld, %ld", tcp->u_arg[2], tcp->u_arg[3]);
}
}
int
sys_epoll_wait(tcp)
struct tcb *tcp;
{
epoll_wait_common(tcp);
return 0;
}
int
sys_epoll_pwait(tcp)
struct tcb *tcp;
{
epoll_wait_common(tcp);
if (exiting(tcp))
print_sigset(tcp, tcp->u_arg[4], 0);
return 0;
}
int
sys_io_setup(tcp)
struct tcb *tcp;
{
if (entering(tcp))
tprintf("%ld, ", tcp->u_arg[0]);
else {
if (syserror(tcp))
tprintf("0x%0lx", tcp->u_arg[1]);
else {
unsigned long user_id;
if (umove(tcp, tcp->u_arg[1], &user_id) == 0)
tprintf("{%lu}", user_id);
else
tprintf("{...}");
}
}
return 0;
}
int
sys_io_destroy(tcp)
struct tcb *tcp;
{
if (entering(tcp))
tprintf("%lu", tcp->u_arg[0]);
return 0;
}
int
sys_io_submit(tcp)
struct tcb *tcp;
{
long nr;
if (entering(tcp)) {
tprintf("%lu, %ld, ", tcp->u_arg[0], tcp->u_arg[1]);
nr = tcp->u_arg[1];
/* and if nr is negative? */
if (nr == 0)
tprintf("{}");
else {
#ifdef HAVE_LIBAIO_H
long i;
struct iocb *iocbp, **iocbs = (void *)tcp->u_arg[2];
for (i = 0; i < nr; i++, iocbs++) {
struct iocb iocb;
if (i == 0)
tprintf("{");
else
tprintf(", ");
if (umove(tcp, (unsigned long)iocbs, &iocbp) ||
umove(tcp, (unsigned long)iocbp, &iocb)) {
tprintf("{...}");
continue;
}
tprintf("{%p, %u, %hu, %hu, %d}",
iocb.data, iocb.key,
iocb.aio_lio_opcode,
iocb.aio_reqprio, iocb.aio_fildes);
}
if (i)
tprintf("}");
#else
tprintf("{...}");
#endif
}
}
return 0;
}
int
sys_io_cancel(tcp)
struct tcb *tcp;
{
if (entering(tcp)) {
#ifdef HAVE_LIBAIO_H
struct iocb iocb;
#endif
tprintf("%lu, ", tcp->u_arg[0]);
#ifdef HAVE_LIBAIO_H
if (umove(tcp, tcp->u_arg[1], &iocb) == 0) {
tprintf("{%p, %u, %hu, %hu, %d}, ",
iocb.data, iocb.key,
iocb.aio_lio_opcode,
iocb.aio_reqprio, iocb.aio_fildes);
} else
#endif
tprintf("{...}, ");
} else {
if (tcp->u_rval < 0)
tprintf("{...}");
else {
#ifdef HAVE_LIBAIO_H
struct io_event event;
if (umove(tcp, tcp->u_arg[2], &event) == 0)
tprintf("{%p, %p, %ld, %ld}",
event.data, event.obj,
event.res, event.res2);
else
#endif
tprintf("{...}");
}
}
return 0;
}
int
sys_io_getevents(struct tcb * tcp)
{
if (entering(tcp)) {
tprintf("%ld, %ld, %ld, ", tcp->u_arg[0], tcp->u_arg[1],
tcp->u_arg[2]);
} else {
if (tcp->u_rval == 0) {
tprintf("{}");
} else {
#ifdef HAVE_LIBAIO_H
struct io_event *events = (void *)tcp->u_arg[3];
long i, nr = tcp->u_rval;
for (i = 0; i < nr; i++, events++) {
struct io_event event;
if (i == 0)
tprintf("{");
else
tprintf(", ");
if (umove(tcp, (unsigned long)events, &event) != 0) {
tprintf("{...}");
continue;
}
tprintf("{%p, %p, %ld, %ld}", event.data,
event.obj, event.res, event.res2);
}
tprintf("}, ");
#else
tprintf("{...}");
#endif
}
print_timespec(tcp, tcp->u_arg[4]);
}
return 0;
}
#endif /* LINUX */
int
sys_select(tcp)
struct tcb *tcp;
{
return decode_select(tcp, tcp->u_arg, BITNESS_CURRENT);
}
#ifdef LINUX
int
sys_pselect6(struct tcb *tcp)
{
int rc = decode_select(tcp, tcp->u_arg, BITNESS_CURRENT);
if (entering(tcp)) {
struct {
void *ss;
unsigned long len;
} data;
if (umove(tcp, tcp->u_arg[5], &data) < 0)
tprintf(", %#lx", tcp->u_arg[5]);
else {
tprintf(", {");
if (data.len < sizeof(long))
tprintf("%#lx", (long)data.ss);
else
print_sigset(tcp, (long)data.ss, 0);
tprintf(", %lu}", data.len);
}
}
return rc;
}
int
sys_eventfd(tcp)
struct tcb *tcp;
{
if (entering(tcp))
tprintf("%lu", tcp->u_arg[0]);
return 0;
}
#endif