strace/poll.c
Dmitry V. Levin abe89bf315 poll.c: use xs*printf instead of sprintf
* poll.c: Include "xstring.h".
(decode_poll_exiting): Replace sprintf with xsnprintf and xsprintf.
2018-01-07 00:05:42 +00:00

192 lines
5.0 KiB
C

/*
* Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
* Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
* Copyright (c) 1999-2017 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 <poll.h>
#include "xstring.h"
#include "xlat/pollflags.h"
static bool
print_pollfd(struct tcb *tcp, void *elem_buf, size_t elem_size, void *data)
{
const struct pollfd *fds = elem_buf;
tprints("{fd=");
printfd(tcp, fds->fd);
if (fds->fd >= 0) {
tprints(", events=");
printflags(pollflags, (unsigned short) fds->events, "POLL???");
}
tprints("}");
return true;
}
static void
decode_poll_entering(struct tcb *tcp)
{
const kernel_ulong_t addr = tcp->u_arg[0];
const unsigned int nfds = tcp->u_arg[1];
struct pollfd fds;
print_array(tcp, addr, nfds, &fds, sizeof(fds),
umoven_or_printaddr, print_pollfd, 0);
tprintf(", %u, ", nfds);
}
static int
decode_poll_exiting(struct tcb *const tcp, const kernel_ulong_t pts)
{
struct pollfd fds;
const unsigned int nfds = tcp->u_arg[1];
const unsigned long size = sizeof(fds) * nfds;
const kernel_ulong_t start = tcp->u_arg[0];
const kernel_ulong_t end = start + size;
kernel_ulong_t cur;
const unsigned int max_printed =
abbrev(tcp) ? max_strlen : -1U;
unsigned int printed;
static char outstr[1024];
char *outptr;
#define end_outstr (outstr + sizeof(outstr))
if (syserror(tcp))
return 0;
if (tcp->u_rval == 0) {
tcp->auxstr = "Timeout";
return RVAL_STR;
}
if (!verbose(tcp) || !start || !nfds ||
size / sizeof(fds) != nfds || end < start)
return 0;
outptr = outstr;
for (printed = 0, cur = start; cur < end; cur += sizeof(fds)) {
if (umove(tcp, cur, &fds) < 0) {
if (outptr == outstr)
*outptr++ = '[';
else
outptr = stpcpy(outptr, ", ");
outptr += xsnprintf(outptr,
sizeof(outstr) - (outptr - outstr),
"%#" PRI_klx, cur);
break;
}
if (!fds.revents)
continue;
if (outptr == outstr)
*outptr++ = '[';
else
outptr = stpcpy(outptr, ", ");
if (printed >= max_printed) {
outptr = stpcpy(outptr, "...");
break;
}
static const char fmt[] = "{fd=%d, revents=";
char fdstr[sizeof(fmt) + sizeof(int) * 3];
xsprintf(fdstr, fmt, fds.fd);
const char *flagstr = sprintflags("", pollflags,
(unsigned short) fds.revents);
if (outptr + strlen(fdstr) + strlen(flagstr) + 1 >=
end_outstr - (2 + 2 * sizeof(long) + sizeof(", ], ..."))) {
outptr = stpcpy(outptr, "...");
break;
}
outptr = stpcpy(outptr, fdstr);
outptr = stpcpy(outptr, flagstr);
*outptr++ = '}';
++printed;
}
if (outptr != outstr)
*outptr++ = ']';
*outptr = '\0';
if (pts) {
const char *str = sprint_timespec(tcp, pts);
if (outptr + sizeof(", left ") + strlen(str) < end_outstr) {
outptr = stpcpy(outptr, outptr == outstr ? "left " : ", left ");
outptr = stpcpy(outptr, str);
} else {
outptr = stpcpy(outptr, ", ...");
}
}
if (outptr == outstr)
return 0;
tcp->auxstr = outstr;
return RVAL_STR;
#undef end_outstr
}
SYS_FUNC(poll)
{
if (entering(tcp)) {
decode_poll_entering(tcp);
int timeout = tcp->u_arg[2];
#ifdef INFTIM
if (INFTIM == timeout)
tprints("INFTIM");
else
#endif
tprintf("%d", timeout);
return 0;
} else {
return decode_poll_exiting(tcp, 0);
}
}
SYS_FUNC(ppoll)
{
if (entering(tcp)) {
decode_poll_entering(tcp);
print_timespec(tcp, tcp->u_arg[2]);
tprints(", ");
/* NB: kernel requires arg[4] == NSIG_BYTES */
print_sigset_addr_len(tcp, tcp->u_arg[3], tcp->u_arg[4]);
tprintf(", %" PRI_klu, tcp->u_arg[4]);
return 0;
} else {
return decode_poll_exiting(tcp, tcp->u_arg[2]);
}
}