1 files changed, 113 insertions, 0 deletions
diff --git a/lib/libc/gen/usleep.c b/lib/libc/gen/usleep.c
new file mode 100644
index 0000000..4b7d3cc
--- /dev/null
+++ b/lib/libc/gen/usleep.c
@@ -0,0 +1,113 @@
+/*
+ * 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)
+static char sccsid[] = "@(#)usleep.c	8.1 (Berkeley) 6/4/93";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/time.h>
+#include <signal.h>
+#include <unistd.h>
+#ifdef  _THREAD_SAFE
+#include <pthread.h>
+#include "pthread_private.h"
+#endif
+
+#ifndef _THREAD_SAFE
+static void
+sleephandler()
+{
+	return;
+}
+#endif	/* _THREAD_SAFE */
+
+
+void
+usleep(useconds)
+	unsigned int useconds;
+{
+#ifdef _THREAD_SAFE
+	struct timespec time_to_sleep;
+	struct timespec time_remaining;
+
+	if (useconds) {
+		time_to_sleep.tv_nsec = (useconds % 1000000) * 1000;
+		time_to_sleep.tv_sec = useconds / 1000000;
+		do {
+			nanosleep(&time_to_sleep, &time_remaining);
+			time_to_sleep = time_remaining;
+		} while (time_to_sleep.tv_sec != 0 &&
+			 time_to_sleep.tv_nsec != 0);
+	}
+#else
+	struct timespec time_to_sleep;
+	struct timespec time_remaining;
+	struct sigaction act, oact;
+	sigset_t mask, omask;
+
+	if (useconds != 0) {
+		time_to_sleep.tv_nsec = (useconds % 1000000) * 1000;
+		time_to_sleep.tv_sec = useconds / 1000000;
+
+		/*
+		 * Set up handler to interrupt signanosleep and ensure
+		 * SIGARLM is not blocked.  Block SIGALRM while fiddling
+		 * with things.
+		 */
+		memset(&act, 0, sizeof(act));
+		act.sa_handler = sleephandler;
+		sigemptyset(&mask);
+		sigaddset(&mask, SIGALRM);
+		sigprocmask(SIG_BLOCK, &mask, &omask);
+		sigaction(SIGALRM, &act, &oact);
+		mask = omask;
+		sigdelset(&mask, SIGALRM);
+
+		/*
+		 * signanosleep() uses the given mask for the lifetime of
+		 * the syscall only - it resets on return.  Note that the
+		 * old sleep explicitly unblocks SIGALRM during the sleep.
+		 */
+
+		do {
+			signanosleep(&time_to_sleep, &time_remaining, &mask);
+			time_to_sleep = time_remaining;
+		} while (time_to_sleep.tv_sec != 0 &&
+			 time_to_sleep.tv_nsec != 0);
+
+		/* Unwind */
+		sigaction(SIGALRM, &oact, (struct sigaction *)0);
+		sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);
+	}
+#endif	/* _THREAD_SAFE */
+}