initial import of NetBSD tree

1 files changed, 119 insertions, 0 deletions

diff --git a/lib/libc/gen/sleep.c b/lib/libc/gen/sleep.c
new file mode 100644
index 00000000000..b090c5959d7
--- /dev/null
+++ b/lib/libc/gen/sleep.c
@@ -0,0 +1,119 @@
+/*	$NetBSD: sleep.c,v 1.10 1995/05/03 12:52:43 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[] = "@(#)sleep.c	8.1 (Berkeley) 6/4/93";
+#else
+static char rcsid[] = "$NetBSD: sleep.c,v 1.10 1995/05/03 12:52:43 mycroft Exp $";
+#endif
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/time.h>
+#include <signal.h>
+#include <unistd.h>
+
+unsigned int
+sleep(seconds)
+	unsigned int seconds;
+{
+	struct itimerval itv, oitv;
+	struct sigaction act, oact;
+	struct timeval diff;
+	sigset_t set, oset;
+	static void sleephandler();
+
+	if (!seconds)
+		return 0;
+
+	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 = seconds;
+	itv.it_value.tv_usec = 0;
+	timerclear(&diff);
+	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 {
+			/*
+			 * The existing timer was scheduled to fire 
+			 * before ours, so we compute the time diff
+			 * so we can add it back in the end.
+			 */
+			timersub(&itv.it_value, &oitv.it_value, &diff);
+			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  = 1;
+			oitv.it_value.tv_usec = 0;
+
+			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);
+
+	if (timerisset(&diff))
+		timeradd(&itv.it_value, &diff, &itv.it_value);
+
+	return (itv.it_value.tv_sec);
+}
+
+static void
+sleephandler()
+{
+
+}