diff options
author | Theo de Raadt <deraadt@cvs.openbsd.org> | 1995-10-18 08:53:40 +0000 |
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committer | Theo de Raadt <deraadt@cvs.openbsd.org> | 1995-10-18 08:53:40 +0000 |
commit | d6583bb2a13f329cf0332ef2570eb8bb8fc0e39c (patch) | |
tree | ece253b876159b39c620e62b6c9b1174642e070e /lib/libc/gen/usleep.c |
initial import of NetBSD tree
Diffstat (limited to 'lib/libc/gen/usleep.c')
-rw-r--r-- | lib/libc/gen/usleep.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/lib/libc/gen/usleep.c b/lib/libc/gen/usleep.c new file mode 100644 index 00000000000..23b7279cff1 --- /dev/null +++ b/lib/libc/gen/usleep.c @@ -0,0 +1,108 @@ +/* $NetBSD: usleep.c,v 1.7 1995/05/03 12:52:44 mycroft Exp $ */ + +/* + * Copyright (c) 1989, 1993 + * The Regents of the University of California. 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 the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +#if 0 +static char sccsid[] = "@(#)usleep.c 8.1 (Berkeley) 6/4/93"; +#else +static char rcsid[] = "$NetBSD: usleep.c,v 1.7 1995/05/03 12:52:44 mycroft Exp $"; +#endif +#endif /* LIBC_SCCS and not lint */ + +#include <sys/time.h> +#include <signal.h> +#include <unistd.h> + +#define TICK 10000 /* system clock resolution in microseconds */ + +void +usleep(useconds) + unsigned int useconds; +{ + struct itimerval itv, oitv; + struct sigaction act, oact; + sigset_t set, oset; + static void sleephandler(); + + if (!useconds) + return; + + sigemptyset(&set); + sigaddset(&set, SIGALRM); + sigprocmask(SIG_BLOCK, &set, &oset); + + act.sa_handler = sleephandler; + act.sa_flags = 0; + sigemptyset(&act.sa_mask); + sigaction(SIGALRM, &act, &oact); + + timerclear(&itv.it_interval); + itv.it_value.tv_sec = useconds / 1000000; + itv.it_value.tv_usec = useconds % 1000000; + setitimer(ITIMER_REAL, &itv, &oitv); + + if (timerisset(&oitv.it_value)) { + if (timercmp(&oitv.it_value, &itv.it_value, >)) { + timersub(&oitv.it_value, &itv.it_value, &oitv.it_value); + } else { + itv.it_value = oitv.it_value; + /* + * This is a hack, but we must have time to return + * from the setitimer after the alarm or else it'll + * be restarted. And, anyway, sleep never did + * anything more than this before. + */ + oitv.it_value.tv_sec = 0; + oitv.it_value.tv_usec = 2 * TICK; + + setitimer(ITIMER_REAL, &itv, NULL); + } + } + + set = oset; + sigdelset(&set, SIGALRM); + (void) sigsuspend(&set); + + sigaction(SIGALRM, &oact, NULL); + sigprocmask(SIG_SETMASK, &oset, NULL); + + (void) setitimer(ITIMER_REAL, &oitv, &itv); +} + +static void +sleephandler() +{ + +} |