diff options
Diffstat (limited to 'lib/libpthread/uthread/uthread_select.c')
| -rw-r--r-- | lib/libpthread/uthread/uthread_select.c | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/lib/libpthread/uthread/uthread_select.c b/lib/libpthread/uthread/uthread_select.c new file mode 100644 index 00000000000..d6202db0140 --- /dev/null +++ b/lib/libpthread/uthread/uthread_select.c @@ -0,0 +1,177 @@ +/* + * 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 REGENTS 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. + * + */ +#include <unistd.h> +#include <errno.h> +#include <string.h> +#include <sys/types.h> +#include <sys/time.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) +{ + fd_set read_locks, write_locks, rdwr_locks; + struct timespec ts; + struct timeval zero_timeout = {0, 0}; + int i, ret = 0, got_all_locks = 1; + struct pthread_select_data data; + + if (numfds > _thread_dtablesize) { + numfds = _thread_dtablesize; + } + /* Check if a timeout was specified: */ + if (timeout) { + /* Convert the timeval to a timespec: */ + TIMEVAL_TO_TIMESPEC(timeout, &ts); + + /* Set the wake up time: */ + _thread_kern_set_timeout(&ts); + } else { + /* Wait for ever: */ + _thread_kern_set_timeout(NULL); + } + + FD_ZERO(&read_locks); + FD_ZERO(&write_locks); + FD_ZERO(&rdwr_locks); + + /* lock readfds */ + if (readfds || writefds || exceptfds) { + for (i = 0; i < numfds; i++) { + if ((readfds && (FD_ISSET(i, readfds))) || (exceptfds && FD_ISSET(i, exceptfds))) { + if (writefds && FD_ISSET(i, writefds)) { + if ((ret = _FD_LOCK(i, FD_RDWR, NULL)) != 0) { + got_all_locks = 0; + break; + } + FD_SET(i, &rdwr_locks); + } else { + if ((ret = _FD_LOCK(i, FD_READ, NULL)) != 0) { + got_all_locks = 0; + break; + } + FD_SET(i, &read_locks); + } + } else { + if (writefds && FD_ISSET(i, writefds)) { + if ((ret = _FD_LOCK(i, FD_WRITE, NULL)) != 0) { + got_all_locks = 0; + break; + } + FD_SET(i, &write_locks); + } + } + } + } + if (got_all_locks) { + data.nfds = numfds; + FD_ZERO(&data.readfds); + FD_ZERO(&data.writefds); + FD_ZERO(&data.exceptfds); + if (readfds != NULL) { + memcpy(&data.readfds, readfds, sizeof(data.readfds)); + } + if (writefds != NULL) { + memcpy(&data.writefds, writefds, sizeof(data.writefds)); + } + if (exceptfds != NULL) { + memcpy(&data.exceptfds, exceptfds, sizeof(data.exceptfds)); + } + if ((ret = _thread_sys_select(data.nfds, &data.readfds, &data.writefds, &data.exceptfds, &zero_timeout)) == 0) { + data.nfds = numfds; + FD_ZERO(&data.readfds); + FD_ZERO(&data.writefds); + FD_ZERO(&data.exceptfds); + if (readfds != NULL) { + memcpy(&data.readfds, readfds, sizeof(data.readfds)); + } + if (writefds != NULL) { + memcpy(&data.writefds, writefds, sizeof(data.writefds)); + } + if (exceptfds != NULL) { + memcpy(&data.exceptfds, exceptfds, sizeof(data.exceptfds)); + } + _thread_run->data.select_data = &data; + _thread_run->interrupted = 0; + _thread_kern_sched_state(PS_SELECT_WAIT, __FILE__, __LINE__); + if (_thread_run->interrupted) { + errno = EINTR; + ret = -1; + } else + ret = data.nfds; + } + } + /* clean up the locks */ + for (i = 0; i < numfds; i++) + if (FD_ISSET(i, &read_locks)) + _FD_UNLOCK(i, FD_READ); + for (i = 0; i < numfds; i++) + if (FD_ISSET(i, &rdwr_locks)) + _FD_UNLOCK(i, FD_RDWR); + for (i = 0; i < numfds; i++) + if (FD_ISSET(i, &write_locks)) + _FD_UNLOCK(i, FD_WRITE); + + if (ret >= 0) { + if (readfds != NULL) { + for (i = 0; i < numfds; i++) { + if (FD_ISSET(i, readfds) && + !FD_ISSET(i, &data.readfds)) { + FD_CLR(i, readfds); + } + } + } + if (writefds != NULL) { + for (i = 0; i < numfds; i++) { + if (FD_ISSET(i, writefds) && + !FD_ISSET(i, &data.writefds)) { + FD_CLR(i, writefds); + } + } + } + if (exceptfds != NULL) { + for (i = 0; i < numfds; i++) { + if (FD_ISSET(i, exceptfds) && + !FD_ISSET(i, &data.exceptfds)) { + FD_CLR(i, exceptfds); + } + } + } + } + + return (ret); +} +#endif |