/* * Copyright (c) 1995-1998 John Birrell * 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 #include #include #include #include #ifdef _THREAD_SAFE #include #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 = _thread_fd_lock(i, FD_RDWR, NULL, __FILE__, __LINE__)) != 0) { got_all_locks = 0; break; } FD_SET(i, &rdwr_locks); } else { if ((ret = _thread_fd_lock(i, FD_READ, NULL, __FILE__, __LINE__)) != 0) { got_all_locks = 0; break; } FD_SET(i, &read_locks); } } else { if (writefds && FD_ISSET(i, writefds)) { if ((ret = _thread_fd_lock(i, FD_WRITE, NULL, __FILE__, __LINE__)) != 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)) _thread_fd_unlock(i, FD_READ); for (i = 0; i < numfds; i++) if (FD_ISSET(i, &rdwr_locks)) _thread_fd_unlock(i, FD_RDWR); for (i = 0; i < numfds; i++) if (FD_ISSET(i, &write_locks)) _thread_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