aosp12/external/strace/desc.c

265 lines
6.4 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>
* Copyright (c) 1999-2018 The strace developers.
* 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.
*/
#include "defs.h"
#include "xstring.h"
SYS_FUNC(close)
{
printfd(tcp, tcp->u_arg[0]);
return RVAL_DECODED;
}
SYS_FUNC(dup)
{
printfd(tcp, tcp->u_arg[0]);
return RVAL_DECODED | RVAL_FD;
}
static int
do_dup2(struct tcb *tcp, int flags_arg)
{
printfd(tcp, tcp->u_arg[0]);
tprints(", ");
printfd(tcp, tcp->u_arg[1]);
if (flags_arg >= 0) {
tprints(", ");
printflags(open_mode_flags, tcp->u_arg[flags_arg], "O_???");
}
return RVAL_DECODED | RVAL_FD;
}
SYS_FUNC(dup2)
{
return do_dup2(tcp, -1);
}
SYS_FUNC(dup3)
{
return do_dup2(tcp, 2);
}
static int
decode_select(struct tcb *const tcp, const kernel_ulong_t *const args,
void (*const print_tv_ts) (struct tcb *, kernel_ulong_t),
const char * (*const sprint_tv_ts) (struct tcb *, kernel_ulong_t))
{
int i, j;
int nfds, fdsize;
fd_set *fds = NULL;
const char *sep;
kernel_ulong_t addr;
/* Kernel truncates args[0] to int, we do the same. */
nfds = (int) args[0];
/* Kernel rejects negative nfds, so we don't parse it either. */
if (nfds < 0)
nfds = 0;
/* Beware of select(2^31-1, NULL, NULL, NULL) and similar... */
if (nfds > 1024*1024)
nfds = 1024*1024;
/*
* We had bugs a-la "while (j < args[0])" and "umoven(args[0])" below.
* Instead of args[0], use nfds for fd count, fdsize for array lengths.
*/
fdsize = (((nfds + 7) / 8) + current_wordsize-1) & -current_wordsize;
if (entering(tcp)) {
tprintf("%d", (int) args[0]);
if (verbose(tcp) && fdsize > 0)
fds = malloc(fdsize);
for (i = 0; i < 3; i++) {
addr = args[i+1];
tprints(", ");
if (!fds) {
printaddr(addr);
continue;
}
if (umoven_or_printaddr(tcp, addr, fdsize, fds))
continue;
tprints("[");
for (j = 0, sep = "";; j++) {
j = next_set_bit(fds, j, nfds);
if (j < 0)
break;
tprints(sep);
printfd(tcp, j);
sep = " ";
}
tprints("]");
}
free(fds);
tprints(", ");
print_tv_ts(tcp, args[4]);
} else {
static char outstr[1024];
char *outptr;
#define end_outstr (outstr + sizeof(outstr))
int ready_fds;
if (syserror(tcp))
return 0;
ready_fds = tcp->u_rval;
if (ready_fds == 0) {
tcp->auxstr = "Timeout";
return RVAL_STR;
}
fds = malloc(fdsize);
outptr = outstr;
sep = "";
for (i = 0; i < 3 && ready_fds > 0; i++) {
int first = 1;
addr = args[i+1];
if (!addr || !fds || umoven(tcp, addr, fdsize, fds) < 0)
continue;
for (j = 0;; j++) {
j = next_set_bit(fds, j, nfds);
if (j < 0)
break;
/* +2 chars needed at the end: ']',NUL */
if (outptr < end_outstr - (sizeof(", except [") + sizeof(int)*3 + 2)) {
if (first) {
outptr = xappendstr(outstr,
outptr,
"%s%s [%u",
sep,
i == 0 ? "in" : i == 1 ? "out" : "except",
j
);
first = 0;
sep = ", ";
} else {
outptr = xappendstr(outstr,
outptr,
" %u", j);
}
}
if (--ready_fds == 0)
break;
}
if (outptr != outstr)
*outptr++ = ']';
}
free(fds);
/* This contains no useful information on SunOS. */
if (args[4]) {
const char *str = sprint_tv_ts(tcp, args[4]);
if (outptr + sizeof("left ") + strlen(sep) + strlen(str) < end_outstr) {
outptr = xappendstr(outstr, outptr,
"%sleft %s", sep, str);
}
}
*outptr = '\0';
tcp->auxstr = outstr;
return RVAL_STR;
#undef end_outstr
}
return 0;
}
#if HAVE_ARCH_OLD_SELECT
SYS_FUNC(oldselect)
{
kernel_ulong_t *args =
fetch_indirect_syscall_args(tcp, tcp->u_arg[0], 5);
if (args) {
return decode_select(tcp, args, print_timeval, sprint_timeval);
} else {
if (entering(tcp))
printaddr(tcp->u_arg[0]);
return RVAL_DECODED;
}
}
#endif /* HAVE_ARCH_OLD_SELECT */
#ifdef ALPHA
SYS_FUNC(osf_select)
{
return decode_select(tcp, tcp->u_arg, print_timeval32, sprint_timeval32);
}
#endif
SYS_FUNC(select)
{
return decode_select(tcp, tcp->u_arg, print_timeval, sprint_timeval);
}
static int
umove_kulong_array_or_printaddr(struct tcb *const tcp, const kernel_ulong_t addr,
kernel_ulong_t *const ptr, const size_t n)
{
#ifndef current_klongsize
if (current_klongsize < sizeof(*ptr)) {
uint32_t ptr32[n];
int r = umove_or_printaddr(tcp, addr, &ptr32);
if (!r) {
size_t i;
for (i = 0; i < n; ++i)
ptr[i] = ptr32[i];
}
return r;
}
#endif /* !current_klongsize */
return umoven_or_printaddr(tcp, addr, n * sizeof(*ptr), ptr);
}
SYS_FUNC(pselect6)
{
int rc = decode_select(tcp, tcp->u_arg, print_timespec, sprint_timespec);
if (entering(tcp)) {
kernel_ulong_t data[2];
tprints(", ");
if (!umove_kulong_array_or_printaddr(tcp, tcp->u_arg[5],
data, ARRAY_SIZE(data))) {
tprints("{");
/* NB: kernel requires data[1] == NSIG_BYTES */
print_sigset_addr_len(tcp, data[0], data[1]);
tprintf(", %" PRI_klu "}", data[1]);
}
}
return rc;
}