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/* Copyright (C) 2008 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by David Bartley <dtbartle@csclub.uwaterloo.ca>, 2008.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <sysdep-cancel.h>
#include <sys/select.h>
#include <sys/poll.h>
#include <errno.h>
#include <memory.h>
#include <assert.h>
int
__pselect (int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
const struct timespec *timeout, const sigset_t *sigmask)
{
if (nfds < 0 || nfds > FD_SETSIZE)
{
__set_errno(EINVAL);
return -1;
}
/* Fill pollfd structure. */
int pfd_len = nfds * sizeof(struct pollfd);
int use_alloca = __libc_use_alloca (pfd_len);
struct pollfd *pfd;
if (use_alloca)
pfd = alloca (pfd_len);
else
{
pfd = malloc (pfd_len);
if (!pfd)
return -1;
}
int fd;
nfds_t i = 0;
for (fd = 0; fd < nfds; fd++)
{
if ((readfds && FD_ISSET (fd, readfds)) ||
(writefds && FD_ISSET (fd, writefds)) ||
(exceptfds && FD_ISSET (fd, exceptfds)))
{
pfd[i].fd = fd;
pfd[i].events = 0;
pfd[i].revents = 0;
if (readfds && FD_ISSET (fd, readfds))
pfd[i].events |= POLLRDNORM;
if (writefds && FD_ISSET (fd, writefds))
pfd[i].events |= POLLWRNORM;
if (exceptfds && FD_ISSET (fd, exceptfds))
pfd[i].events |= POLLRDBAND;
i++;
}
}
nfds_t num_pfd = i;
/* ppoll is cancelable so don't implement cancellation here. */
int result = ppoll (pfd, num_pfd, timeout, sigmask);
if (result == -1)
{
if (!use_alloca)
free (pfd);
return -1;
}
/* Check for POLLNVAL. */
for (i = 0; i < num_pfd; i++)
{
if (pfd[i].revents & POLLNVAL)
{
if (!use_alloca)
free (pfd);
__set_errno (EBADFD);
return -1;
}
}
/* clear fd_set's */
for (fd = 0; fd < nfds; fd++)
{
if (readfds)
FD_CLR (fd, readfds);
if (writefds)
FD_CLR (fd, writefds);
if (exceptfds)
FD_CLR (fd, exceptfds);
}
/* Fill fd_set's. */
int bits = 0;
for (i = 0; i < num_pfd; i++)
{
fd = pfd[i].fd;
int events = pfd[i].events;
int revents = pfd[i].revents;
assert (fd < nfds);
if (readfds && ((revents & POLLRDNORM) || ((events & POLLRDNORM)
&& (revents & (POLLHUP | POLLERR)))))
{
__FD_SET (fd, readfds);
bits++;
}
if (writefds && ((revents & POLLWRNORM) || ((events & POLLWRNORM)
&& (revents & (POLLHUP | POLLERR)))))
{
__FD_SET (fd, writefds);
bits++;
}
if (exceptfds && ((revents & POLLRDBAND) || ((events & POLLRDBAND)
&& (revents & (POLLHUP | POLLERR)))))
{
__FD_SET (fd, exceptfds);
bits++;
}
}
if (!use_alloca)
free (pfd);
return bits;
}
weak_alias (__pselect, pselect)
strong_alias (__pselect, __libc_pselect)
LIBC_CANCEL_HANDLED (); /* handled by ppoll */
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