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authorTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
committerTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
commitd6583bb2a13f329cf0332ef2570eb8bb8fc0e39c (patch)
treeece253b876159b39c620e62b6c9b1174642e070e /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.c108
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()
+{
+
+}