Return to sleep.c CVS log

Up to [CSRG BSD Unix] / 43BSDReno / lib / libc / gen

Annotation of 43BSDReno/lib/libc/gen/sleep.c, revision 1.1.1.1

1.1       root        1: /*
                      2:  * Copyright (c) 1989 The Regents of the University of California.
                      3:  * All rights reserved.
                      4:  *
                      5:  * Redistribution and use in source and binary forms are permitted
                      6:  * provided that: (1) source distributions retain this entire copyright
                      7:  * notice and comment, and (2) distributions including binaries display
                      8:  * the following acknowledgement:  ``This product includes software
                      9:  * developed by the University of California, Berkeley and its contributors''
                     10:  * in the documentation or other materials provided with the distribution
                     11:  * and in all advertising materials mentioning features or use of this
                     12:  * software. Neither the name of the University nor the names of its
                     13:  * contributors may be used to endorse or promote products derived
                     14:  * from this software without specific prior written permission.
                     15:  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
                     16:  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
                     17:  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
                     18:  */
                     19: 
                     20: #if defined(LIBC_SCCS) && !defined(lint)
                     21: static char sccsid[] = "@(#)sleep.c    5.5 (Berkeley) 6/1/90";
                     22: #endif /* LIBC_SCCS and not lint */
                     23: 
                     24: #include <sys/time.h>
                     25: #include <sys/signal.h>
                     26: 
                     27: #define        setvec(vec, a) \
                     28:        vec.sv_handler = a; vec.sv_mask = vec.sv_onstack = 0
                     29: 
                     30: static int ringring;
                     31: 
                     32: sleep(seconds)
                     33:        unsigned int seconds;
                     34: {
                     35:        register struct itimerval *itp;
                     36:        struct itimerval itv, oitv;
                     37:        struct sigvec vec, ovec;
                     38:        long omask;
                     39:        void sleephandler();
                     40: 
                     41:        itp = &itv;
                     42:        if (!seconds)
                     43:                return;
                     44:        timerclear(&itp->it_interval);
                     45:        timerclear(&itp->it_value);
                     46:        if (setitimer(ITIMER_REAL, itp, &oitv) < 0)
                     47:                return;
                     48:        itp->it_value.tv_sec = seconds;
                     49:        if (timerisset(&oitv.it_value)) {
                     50:                if (timercmp(&oitv.it_value, &itp->it_value, >))
                     51:                        oitv.it_value.tv_sec -= itp->it_value.tv_sec;
                     52:                else {
                     53:                        itp->it_value = oitv.it_value;
                     54:                        /*
                     55:                         * This is a hack, but we must have time to return
                     56:                         * from the setitimer after the alarm or else it'll
                     57:                         * be restarted.  And, anyway, sleep never did
                     58:                         * anything more than this before.
                     59:                         */
                     60:                        oitv.it_value.tv_sec = 1;
                     61:                        oitv.it_value.tv_usec = 0;
                     62:                }
                     63:        }
                     64:        setvec(vec, sleephandler);
                     65:        (void) sigvec(SIGALRM, &vec, &ovec);
                     66:        omask = sigblock(sigmask(SIGALRM));
                     67:        ringring = 0;
                     68:        (void) setitimer(ITIMER_REAL, itp, (struct itimerval *)0);
                     69:        while (!ringring)
                     70:                sigpause(omask &~ sigmask(SIGALRM));
                     71:        (void) sigvec(SIGALRM, &ovec, (struct sigvec *)0);
                     72:        (void) sigsetmask(omask);
                     73:        (void) setitimer(ITIMER_REAL, &oitv, (struct itimerval *)0);
                     74: }
                     75: 
                     76: static void
                     77: sleephandler()
                     78: {
                     79:        ringring = 1;
                     80: }

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.