1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #if defined(LIBC_SCCS) && !defined(lint) 35 static char sccsid[] = "@(#)sleep.c 8.1 (Berkeley) 6/4/93"; 36 #endif /* LIBC_SCCS and not lint */ 37 38 #include <sys/time.h> 39 #include <signal.h> 40 #include <unistd.h> 41 #ifdef _THREAD_SAFE 42 #include <pthread.h> 43 #include "pthread_private.h" 44 #endif 45 46 #ifndef _THREAD_SAFE 47 static void 48 sleephandler() 49 { 50 return; 51 } 52 #endif /* _THREAD_SAFE */ 53 54 unsigned int 55 sleep(seconds) 56 unsigned int seconds; 57 { 58 #ifdef _THREAD_SAFE 59 struct timespec time_to_sleep; 60 struct timespec time_remaining; 61 62 if (seconds != 0) { 63 time_to_sleep.tv_sec = seconds; 64 time_to_sleep.tv_nsec = 0; 65 nanosleep(&time_to_sleep, &time_remaining); 66 seconds = time_remaining.tv_sec; 67 if (time_remaining.tv_nsec > 0) 68 seconds++; /* round up */ 69 } 70 return (seconds); 71 #else 72 struct timespec time_to_sleep; 73 struct timespec time_remaining; 74 struct sigaction act, oact; 75 sigset_t mask, omask; 76 int alarm_blocked; 77 78 if (seconds != 0) { 79 time_to_sleep.tv_sec = seconds; 80 time_to_sleep.tv_nsec = 0; 81 82 /* Block SIGALRM while fiddling with it */ 83 sigemptyset(&mask); 84 sigaddset(&mask, SIGALRM); 85 sigprocmask(SIG_BLOCK, &mask, &omask); 86 87 /* Was SIGALRM blocked already? */ 88 alarm_blocked = sigismember(&omask, SIGALRM); 89 90 if (!alarm_blocked) { 91 /* 92 * Set up handler to interrupt signanosleep only if 93 * SIGALRM was unblocked. (Save some syscalls) 94 */ 95 memset(&act, 0, sizeof(act)); 96 act.sa_handler = sleephandler; 97 sigaction(SIGALRM, &act, &oact); 98 } 99 100 /* 101 * signanosleep() uses the given mask for the lifetime of 102 * the syscall only - it resets on return. Note that the 103 * Old sleep explicitly unblocks SIGALRM during the sleep, 104 * we don't do that now since we don't depend on SIGALRM 105 * to end the timout. If the process blocks SIGALRM, it 106 * gets what it asks for. 107 */ 108 signanosleep(&time_to_sleep, &time_remaining, &omask); 109 110 if (!alarm_blocked) { 111 /* Unwind */ 112 sigaction(SIGALRM, &oact, (struct sigaction *)0); 113 sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0); 114 } 115 116 /* return how long is left */ 117 seconds = time_remaining.tv_sec; 118 if (time_remaining.tv_nsec > 0) 119 seconds++; /* round up */ 120 } 121 return (seconds); 122 #endif /* _THREAD_SAFE */ 123 } 124