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/*
* Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL 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.
*
* $FreeBSD$
*/
#include <unistd.h>
#include <errno.h>
#include <poll.h>
#include <stdlib.h>
#include <string.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/fcntl.h>
#include <pthread.h>
#include "pthread_private.h"
#pragma weak select=_select
int
_select(int numfds, fd_set * readfds, fd_set * writefds, fd_set * exceptfds,
struct timeval * timeout)
{
struct pthread *curthread = _get_curthread();
struct timespec ts;
int i, ret = 0, f_wait = 1;
int pfd_index, got_one = 0, fd_count = 0;
struct pthread_poll_data data;
if (numfds > _thread_dtablesize) {
numfds = _thread_dtablesize;
}
/* Check if a timeout was specified: */
if (timeout) {
if (timeout->tv_sec < 0 ||
timeout->tv_usec < 0 || timeout->tv_usec >= 1000000) {
errno = EINVAL;
return (-1);
}
/* Convert the timeval to a timespec: */
TIMEVAL_TO_TIMESPEC(timeout, &ts);
/* Set the wake up time: */
_thread_kern_set_timeout(&ts);
if (ts.tv_sec == 0 && ts.tv_nsec == 0)
f_wait = 0;
} else {
/* Wait for ever: */
_thread_kern_set_timeout(NULL);
}
/* Count the number of file descriptors to be polled: */
if (readfds || writefds || exceptfds) {
for (i = 0; i < numfds; i++) {
if ((readfds && FD_ISSET(i, readfds)) ||
(exceptfds && FD_ISSET(i, exceptfds)) ||
(writefds && FD_ISSET(i, writefds))) {
fd_count++;
}
}
}
/*
* Allocate memory for poll data if it hasn't already been
* allocated or if previously allocated memory is insufficient.
*/
if ((curthread->poll_data.fds == NULL) ||
(curthread->poll_data.nfds < fd_count)) {
data.fds = (struct pollfd *) realloc(curthread->poll_data.fds,
sizeof(struct pollfd) * MAX(128, fd_count));
if (data.fds == NULL) {
errno = ENOMEM;
ret = -1;
}
else {
/*
* Note that the threads poll data always
* indicates what is allocated, not what is
* currently being polled.
*/
curthread->poll_data.fds = data.fds;
curthread->poll_data.nfds = MAX(128, fd_count);
}
}
if (ret == 0) {
/* Setup the wait data. */
data.fds = curthread->poll_data.fds;
data.nfds = fd_count;
/*
* Setup the array of pollfds. Optimize this by
* running the loop in reverse and stopping when
* the number of selected file descriptors is reached.
*/
for (i = numfds - 1, pfd_index = fd_count - 1;
(i >= 0) && (pfd_index >= 0); i--) {
data.fds[pfd_index].events = 0;
if (readfds && FD_ISSET(i, readfds)) {
data.fds[pfd_index].events = POLLRDNORM;
}
if (exceptfds && FD_ISSET(i, exceptfds)) {
data.fds[pfd_index].events |= POLLRDBAND;
}
if (writefds && FD_ISSET(i, writefds)) {
data.fds[pfd_index].events |= POLLWRNORM;
}
if (data.fds[pfd_index].events != 0) {
/*
* Set the file descriptor to be polled and
* clear revents in case of a timeout which
* leaves fds unchanged:
*/
data.fds[pfd_index].fd = i;
data.fds[pfd_index].revents = 0;
pfd_index--;
}
}
if (((ret = __sys_poll(data.fds, data.nfds, 0)) == 0) &&
(f_wait != 0)) {
curthread->data.poll_data = &data;
curthread->interrupted = 0;
_thread_kern_sched_state(PS_SELECT_WAIT, __FILE__, __LINE__);
if (curthread->interrupted) {
errno = EINTR;
data.nfds = 0;
ret = -1;
} else
ret = data.nfds;
}
}
if (ret >= 0) {
numfds = 0;
for (i = 0; i < fd_count; i++) {
/*
* Check the results of the poll and clear
* this file descriptor from the fdset if
* the requested event wasn't ready.
*/
got_one = 0;
if (readfds != NULL) {
if (FD_ISSET(data.fds[i].fd, readfds)) {
if (data.fds[i].revents & (POLLIN |
POLLRDNORM))
got_one = 1;
else
FD_CLR(data.fds[i].fd, readfds);
}
}
if (writefds != NULL) {
if (FD_ISSET(data.fds[i].fd, writefds)) {
if (data.fds[i].revents & (POLLOUT |
POLLWRNORM | POLLWRBAND))
got_one = 1;
else
FD_CLR(data.fds[i].fd,
writefds);
}
}
if (exceptfds != NULL) {
if (FD_ISSET(data.fds[i].fd, exceptfds)) {
if (data.fds[i].revents & (POLLRDBAND |
POLLPRI | POLLHUP | POLLERR |
POLLNVAL))
got_one = 1;
else
FD_CLR(data.fds[i].fd,
exceptfds);
}
}
if (got_one)
numfds++;
}
ret = numfds;
}
return (ret);
}
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