10Sstevel@tonic-gate /*
20Sstevel@tonic-gate * Copyright 1996 Sun Microsystems, Inc. All rights reserved.
30Sstevel@tonic-gate * Use is subject to license terms.
40Sstevel@tonic-gate */
50Sstevel@tonic-gate
60Sstevel@tonic-gate /*
70Sstevel@tonic-gate * Copyright (c) 1985 Regents of the University of California.
80Sstevel@tonic-gate * All rights reserved. The Berkeley software License Agreement
90Sstevel@tonic-gate * specifies the terms and conditions for redistribution.
100Sstevel@tonic-gate */
110Sstevel@tonic-gate
12*722Smuffin #pragma ident "%Z%%M% %I% %E% SMI"
13*722Smuffin
140Sstevel@tonic-gate #include <unistd.h>
150Sstevel@tonic-gate #include <sys/time.h>
160Sstevel@tonic-gate #include <signal.h>
170Sstevel@tonic-gate
180Sstevel@tonic-gate #define USPS 1000000 /* number of microseconds in a second */
190Sstevel@tonic-gate #define TICK (USPS / _sysconf(_SC_CLK_TCK))
200Sstevel@tonic-gate
210Sstevel@tonic-gate #define setvec(vec, a) \
220Sstevel@tonic-gate vec.sv_handler = a; vec.sv_mask = vec.sv_onstack = 0
230Sstevel@tonic-gate
240Sstevel@tonic-gate static int ringring;
250Sstevel@tonic-gate
26*722Smuffin void
usleep(unsigned n)27*722Smuffin usleep(unsigned n)
280Sstevel@tonic-gate {
290Sstevel@tonic-gate static void sleepx();
300Sstevel@tonic-gate int omask;
310Sstevel@tonic-gate struct itimerval itv, oitv;
32*722Smuffin struct itimerval *itp = &itv;
330Sstevel@tonic-gate struct sigvec vec, ovec;
340Sstevel@tonic-gate
350Sstevel@tonic-gate if (n == 0)
360Sstevel@tonic-gate return;
370Sstevel@tonic-gate timerclear(&itp->it_interval);
380Sstevel@tonic-gate timerclear(&itp->it_value);
390Sstevel@tonic-gate if (setitimer(ITIMER_REAL, itp, &oitv) < 0)
400Sstevel@tonic-gate return;
410Sstevel@tonic-gate itp->it_value.tv_sec = n / USPS;
420Sstevel@tonic-gate itp->it_value.tv_usec = n % USPS;
430Sstevel@tonic-gate if (timerisset(&oitv.it_value)) {
440Sstevel@tonic-gate if (timercmp(&oitv.it_value, &itp->it_value, >)) {
450Sstevel@tonic-gate oitv.it_value.tv_sec -= itp->it_value.tv_sec;
460Sstevel@tonic-gate oitv.it_value.tv_usec -= itp->it_value.tv_usec;
470Sstevel@tonic-gate if (oitv.it_value.tv_usec < 0) {
480Sstevel@tonic-gate oitv.it_value.tv_usec += USPS;
490Sstevel@tonic-gate oitv.it_value.tv_sec--;
500Sstevel@tonic-gate }
510Sstevel@tonic-gate } else {
520Sstevel@tonic-gate itp->it_value = oitv.it_value;
530Sstevel@tonic-gate oitv.it_value.tv_sec = 0;
540Sstevel@tonic-gate oitv.it_value.tv_usec = 2 * TICK;
550Sstevel@tonic-gate }
560Sstevel@tonic-gate }
570Sstevel@tonic-gate setvec(vec, sleepx);
580Sstevel@tonic-gate (void) sigvec(SIGALRM, &vec, &ovec);
590Sstevel@tonic-gate omask = sigblock(sigmask(SIGALRM));
600Sstevel@tonic-gate ringring = 0;
610Sstevel@tonic-gate (void) setitimer(ITIMER_REAL, itp, (struct itimerval *)0);
620Sstevel@tonic-gate while (!ringring)
630Sstevel@tonic-gate sigpause(omask &~ sigmask(SIGALRM));
640Sstevel@tonic-gate (void) sigvec(SIGALRM, &ovec, (struct sigvec *)0);
650Sstevel@tonic-gate (void) sigsetmask(omask);
660Sstevel@tonic-gate (void) setitimer(ITIMER_REAL, &oitv, (struct itimerval *)0);
670Sstevel@tonic-gate }
680Sstevel@tonic-gate
690Sstevel@tonic-gate static void
sleepx(void)70*722Smuffin sleepx(void)
710Sstevel@tonic-gate {
720Sstevel@tonic-gate
730Sstevel@tonic-gate ringring = 1;
740Sstevel@tonic-gate }
75