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-rw-r--r--lib/libpthread/thread/thr_select.c206
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diff --git a/lib/libpthread/thread/thr_select.c b/lib/libpthread/thread/thr_select.c
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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>
+#ifdef _THREAD_SAFE
+#include <pthread.h>
+#include "pthread_private.h"
+
+int
+select(int numfds, fd_set * readfds, fd_set * writefds,
+ fd_set * exceptfds, struct timeval * timeout)
+{
+ 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 ((_thread_run->poll_data.fds == NULL) ||
+ (_thread_run->poll_data.nfds < fd_count)) {
+ data.fds = (struct pollfd *) realloc(_thread_run->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.
+ */
+ _thread_run->poll_data.fds = data.fds;
+ _thread_run->poll_data.nfds = MAX(128, fd_count);
+ }
+ }
+ if (ret == 0) {
+ /* Setup the wait data. */
+ data.fds = _thread_run->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 = _thread_sys_poll(data.fds, data.nfds, 0)) == 0) &&
+ (f_wait != 0)) {
+ _thread_run->data.poll_data = &data;
+ _thread_run->interrupted = 0;
+ _thread_kern_sched_state(PS_SELECT_WAIT, __FILE__, __LINE__);
+ if (_thread_run->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);
+}
+#endif
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