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-rw-r--r--sysdeps/unix/clock_nanosleep.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/sysdeps/unix/clock_nanosleep.c b/sysdeps/unix/clock_nanosleep.c
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index 0000000000..a4d00d26d0
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+++ b/sysdeps/unix/clock_nanosleep.c
@@ -0,0 +1,81 @@
+/* High-resolution sleep with the specified clock.
+   Copyright (C) 2000 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <assert.h>
+#include <errno.h>
+#include <sys/time.h>
+
+
+#ifndef CLOCK_P
+# define CLOCK_P(clock) 0
+#endif
+
+
+/* This implementation assumes that these is only a `nanosleep' system
+   call.  So we have to remap all other activities.  */
+int
+clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req,
+		 struct timespec *rem)
+{
+  struct timespec now;
+
+  if (__builtin_expect (req->tv_nsec, 0) < 0
+      || __builtin_expect (req->tv_nsec, 0) >= 1000000000)
+    return EINVAL;
+
+  /* If we got an absolute time, remap it.  */
+  if (flags == TIMER_ABSTIME)
+    {
+      long int nsec;
+      long int sec;
+
+      /* Make sure we use safe data types.  */
+      assert (sizeof (sec) >= sizeof (now.tv_sec));
+
+      /* Get the current time for this clock.  */
+      if (clock_gettime (clock_id, &now) != 0)
+	return errno;
+
+      /* Compute the difference.  */
+      nsec = req->tv_nsec - now.tv_nsec;
+      sec = req->tv_sec - now.tv_sec - (nsec < 0);
+      if (sec < 0)
+	/* The time has already elapsed.  */
+	return 0;
+
+      now.tv_sec = sec;
+      now.tv_nsec = nsec + (nsec < 0 ? 1000000000 : 0);
+
+      /* From now on this is our time.  */
+      req = &now;
+
+      /* Make sure we are not modifying the struct pointed to by REM.  */
+      rem = NULL;
+    }
+  else if (__builtin_expect (flags, 0) != 0)
+    return EINVAL;
+  else if (clock_id != CLOCK_REALTIME)
+    {
+      /* Make sure the clock ID is correct.  */
+      if (__builtin_expect (! CLOCK_P (clock_id), 0))
+	return EINVAL;
+    }
+
+  return __builtin_expect (nanosleep (req, rem), 0) ? errno : 0;
+}