Merge changes between r20213 and r20391 from /fsf/trunk.

git-svn-id: svn://svn.eglibc.org/trunk@20392 7b3dc134-2b1b-0410-93df-9e9f96275f8d

1 files changed, 50 insertions, 0 deletions

diff --git a/libc/sysdeps/posix/alarm.c b/libc/sysdeps/posix/alarm.c
new file mode 100644
index 000000000..730f2c4c7
--- /dev/null
+++ b/libc/sysdeps/posix/alarm.c
@@ -0,0 +1,50 @@
+/* Copyright (C) 1991,1992,1994,1997,2002,2004 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 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <unistd.h>
+#include <sys/time.h>
+
+/* Schedule an alarm.  In SECONDS seconds, the process will get a SIGALRM.
+   If SECONDS is zero, any currently scheduled alarm will be cancelled.
+   The function returns the number of seconds remaining until the last
+   alarm scheduled would have signaled, or zero if there wasn't one.
+   There is no return value to indicate an error, but you can set `errno'
+   to 0 and check its value after calling `alarm', and this might tell you.
+   The signal may come late due to processor scheduling.  */
+unsigned int
+alarm (seconds)
+     unsigned int seconds;
+{
+  struct itimerval old, new;
+  unsigned int retval;
+
+  new.it_interval.tv_usec = 0;
+  new.it_interval.tv_sec = 0;
+  new.it_value.tv_usec = 0;
+  new.it_value.tv_sec = (long int) seconds;
+  if (__setitimer (ITIMER_REAL, &new, &old) < 0)
+    return 0;
+
+  retval = old.it_value.tv_sec;
+  /* Round to the nearest second, but never report zero seconds when
+     the alarm is still set.  */
+  if (old.it_value.tv_usec >= 500000
+      || (retval == 0 && old.it_value.tv_usec > 0))
+    ++retval;
+  return retval;
+}
+libc_hidden_def (alarm)