wait-fd.c (2011B)
1/* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, 13 * software distributed under the License is distributed on an 14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 15 * KIND, either express or implied. See the License for the 16 * specific language governing permissions and limitations 17 * under the License. 18 */ 19 20#include "config.h" 21 22#ifdef ENABLE_WINSOCK 23# include <winsock2.h> 24#else 25# ifdef HAVE_POLL 26# include <poll.h> 27# else 28# include <sys/select.h> 29# endif 30#endif 31 32#ifdef HAVE_POLL 33int guac_wait_for_fd(int fd, int usec_timeout) { 34 35 /* Initialize with single underlying file descriptor */ 36 struct pollfd fds[1] = {{ 37 .fd = fd, 38 .events = POLLIN, 39 .revents = 0 40 }}; 41 42 /* No timeout if usec_timeout is negative */ 43 if (usec_timeout < 0) 44 return poll(fds, 1, -1); 45 46 /* Handle timeout if specified, rounding up to poll()'s granularity */ 47 return poll(fds, 1, (usec_timeout + 999) / 1000); 48 49} 50#else 51int guac_wait_for_fd(int fd, int usec_timeout) { 52 53 fd_set fds; 54 55 /* Initialize fd_set with single underlying file descriptor */ 56 FD_ZERO(&fds); 57 FD_SET(fd, &fds); 58 59 /* No timeout if usec_timeout is negative */ 60 if (usec_timeout < 0) 61 return select(fd + 1, &fds, NULL, NULL, NULL); 62 63 /* Handle timeout if specified */ 64 struct timeval timeout = { 65 .tv_sec = usec_timeout / 1000000, 66 .tv_usec = usec_timeout % 1000000 67 }; 68 69 return select(fd + 1, &fds, NULL, NULL, &timeout); 70 71} 72#endif