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-rw-r--r--io/ppoll.c76
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diff --git a/io/ppoll.c b/io/ppoll.c
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+/* Copyright (C) 2006 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2006.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <limits.h>
+#include <signal.h>
+#include <stddef.h>	/* For NULL.  */
+#include <sys/poll.h>
+#include <sysdep-cancel.h>
+
+
+int
+ppoll (struct pollfd *fds, nfds_t nfds, const struct timespec *timeout,
+       const sigset_t *sigmask)
+{
+  int tval = -1;
+
+  /* poll uses a simple millisecond value.  Convert it.  */
+  if (timeout != NULL)
+    {
+      if (timeout->tv_sec < 0
+	  || timeout->tv_nsec < 0 || timeout->tv_nsec >= 1000000000)
+	{
+	  __set_errno (EINVAL);
+	  return -1;
+	}
+
+      if (timeout->tv_sec > INT_MAX / 1000
+	  || (timeout->tv_sec == INT_MAX / 1000
+	      && ((timeout->tv_nsec + 999999) / 1000000 > INT_MAX % 1000)))
+	/* We cannot represent the timeout in an int value.  Wait
+	   forever.  */
+	tval = -1;
+      else
+	tval = (timeout->tv_sec * 1000
+		+ (timeout->tv_nsec + 999999) / 1000000);
+    }
+
+  /* The setting and restoring of the signal mask and the select call
+     should be an atomic operation.  This can't be done without kernel
+     help.  */
+  sigset_t savemask;
+  if (sigmask != NULL)
+    __sigprocmask (SIG_SETMASK, sigmask, &savemask);
+
+  /* Note the ppoll() is a cancellation point.  But since we call
+     poll() which itself is a cancellation point we do not have
+     to do anything here.  */
+  int retval = __poll (fds, nfds, tval);
+
+  if (sigmask != NULL)
+    __sigprocmask (SIG_SETMASK, &savemask, NULL);
+
+  return retval;
+}
+
+#ifndef ppoll
+/* __poll handles cancellation.  */
+LIBC_CANCEL_HANDLED ();
+#endif