From: Erik van der Kouwe <erik@minix3.org>
Date: Sun, 16 Aug 2009 12:13:33 +0000 (+0000)
Subject: Function nanosleep now checks arguments
X-Git-Tag: v3.1.5~191
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/zpipe.c?a=commitdiff_plain;h=3573bc1abe1c26e167cc68984f1018c06bebdf91;p=minix.git

Function nanosleep now checks arguments
---

diff --git a/lib/posix/_sleep.c b/lib/posix/_sleep.c
index e1f721e0f..21dfc633c 100755
--- a/lib/posix/_sleep.c
+++ b/lib/posix/_sleep.c
@@ -1,18 +1,97 @@
-/*	sleep() - Sleep for a number of seconds.  Author: Erik van der Kouwe
+/*	sleep() - Sleep for a number of seconds.	Author: Erik van der Kouwe
  *								25 July 2009
+ * (Avoids interfering with alarm/setitimer by using select, like usleep)
  */
 
 #include <lib.h>
 #define sleep _sleep
+#define nanosleep _nanosleep
+#include <signal.h>
+#include <unistd.h>
+#include <errno.h>
 #include <time.h>
+#include <sys/select.h>
+#include <sys/time.h>
+
+#define MSEC_PER_SEC 1000
+#define USEC_PER_MSEC 1000
+#define NSEC_PER_USEC 1000
+
+#define USEC_PER_SEC (USEC_PER_MSEC * MSEC_PER_SEC)
+#define NSEC_PER_SEC (NSEC_PER_USEC * USEC_PER_SEC)
+
+int nanosleep(const struct timespec *rqtp, struct timespec *rmtp)
+{
+	struct timeval timeout, timestart = { 0, 0 }, timeend;
+	int errno_select, r;
+
+	/* check parameters */
+	if (!rqtp)
+		return EFAULT;
+
+	if (rqtp->tv_sec < 0 || 
+		rqtp->tv_nsec < 0 ||
+		rqtp->tv_nsec >= NSEC_PER_SEC)
+		return EINVAL;
+
+	/* keep track of start time if needed */
+	if (rmtp)
+	{
+		rmtp->tv_sec = 0;
+		rmtp->tv_nsec = 0;
+		if (gettimeofday(&timestart, NULL) < 0)
+			return -1;
+	}
+
+	/* use select to wait */
+	timeout.tv_sec = rqtp->tv_sec;
+	timeout.tv_usec = (rqtp->tv_nsec + NSEC_PER_USEC - 1) / NSEC_PER_USEC;
+	r = select(0, NULL, NULL, NULL, &timeout);
+
+	/* return remaining time only if requested */
+	/* if select succeeded then we slept all time */
+	if (!rmtp || r >= 0)
+		return r;
+
+	/* measure end time; preserve errno */
+	errno_select = errno;
+	if (gettimeofday(&timeend, NULL) < 0)
+		return -1;
+
+	errno = errno_select;
+
+	/* compute remaining time */
+	rmtp->tv_sec = rqtp->tv_sec - (timeend.tv_sec - timestart.tv_sec);
+	rmtp->tv_nsec = rqtp->tv_nsec - (timeend.tv_usec - timestart.tv_usec) * NSEC_PER_USEC;
+
+	/* bring remaining time into canonical form */
+	while (rmtp->tv_nsec < 0)
+	{
+		rmtp->tv_sec -= 1;
+		rmtp->tv_nsec += NSEC_PER_SEC;
+	}
+
+	while (rmtp->tv_nsec > NSEC_PER_SEC)
+	{
+		rmtp->tv_sec += 1;
+		rmtp->tv_nsec -= NSEC_PER_SEC;
+	}
+
+	/* remaining time must not be negative */
+	if (rmtp->tv_sec < 0)
+	{
+		rmtp->tv_sec = 0;
+		rmtp->tv_nsec = 0;
+	}
+
+	return r;
+}
 
 unsigned sleep(unsigned sleep_seconds)
 {
 	struct timespec rqtp, rmtp;
 
-	/* nanosleep implements this call;
-	 * ignore failure, it cannot be reported
-	 */
+	/* nanosleep implements this call; ignore failure, it cannot be reported */
 	rqtp.tv_sec = sleep_seconds;
 	rqtp.tv_nsec = 0;
 	nanosleep(&rqtp, &rmtp);