From aedb00d04eb7f0b20b6abde702ba94a46577ca68 Mon Sep 17 00:00:00 2001
From: Elliott Hughes <enh@google.com>
Date: Mon, 3 Mar 2014 14:38:20 -0800
Subject: [PATCH] Switch to upstream alarm(3).

The only way the setitimer call can fail is if the unsigned number of seconds is
too large to fit in the kernel's signed number of seconds. If you schedule a
68-year alarm, glibc will fail by returning 0 and BSD will fail by returning -1.

Change-Id: Ic3721b01428f5402d99f31fd7f2ba2cc58805607
---
 libc/Android.mk                               |  2 +-
 .../lib/libc/gen}/alarm.c                     | 21 +++++--------------
 tests/unistd_test.cpp                         |  4 ++++
 3 files changed, 10 insertions(+), 17 deletions(-)
 rename libc/{unistd => upstream-openbsd/lib/libc/gen}/alarm.c (78%)

diff --git a/libc/Android.mk b/libc/Android.mk
index d4ccefbe5..4e6276520 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -104,7 +104,6 @@ libc_common_src_files := \
     stdlib/putenv.c \
     stdlib/setenv.c \
     stdlib/strtod.c \
-    unistd/alarm.c \
     unistd/syslog.c \
     unistd/time.c \
 
@@ -316,6 +315,7 @@ libc_upstream_netbsd_src_files := \
     upstream-netbsd/lib/libc/unistd/killpg.c \
 
 libc_upstream_openbsd_src_files := \
+    upstream-openbsd/lib/libc/gen/alarm.c \
     upstream-openbsd/lib/libc/gen/exec.c \
     upstream-openbsd/lib/libc/gen/fnmatch.c \
     upstream-openbsd/lib/libc/gen/ftok.c \
diff --git a/libc/unistd/alarm.c b/libc/upstream-openbsd/lib/libc/gen/alarm.c
similarity index 78%
rename from libc/unistd/alarm.c
rename to libc/upstream-openbsd/lib/libc/gen/alarm.c
index 53edea949..2af847a46 100644
--- a/libc/unistd/alarm.c
+++ b/libc/upstream-openbsd/lib/libc/gen/alarm.c
@@ -1,3 +1,4 @@
+/*	$OpenBSD: alarm.c,v 1.7 2005/08/08 08:05:33 espie Exp $ */
 /*
  * Copyright (c) 1983, 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -10,7 +11,7 @@
  * 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.
- * 4. Neither the name of the University nor the names of its contributors
+ * 3. 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.
  *
@@ -27,12 +28,6 @@
  * SUCH DAMAGE.
  */
 
-#if defined(LIBC_SCCS) && !defined(lint)
-static char sccsid[] = "@(#)alarm.c	8.1 (Berkeley) 6/4/93";
-#endif /* LIBC_SCCS and not lint */
-#include <sys/cdefs.h>
-//__FBSDID("$FreeBSD: /repoman/r/ncvs/src/lib/libc/gen/alarm.c,v 1.3 2007/01/09 00:27:53 imp Exp $");
-
 /*
  * Backwards compatible alarm.
  */
@@ -40,22 +35,16 @@ static char sccsid[] = "@(#)alarm.c	8.1 (Berkeley) 6/4/93";
 #include <unistd.h>
 
 unsigned int
-alarm(secs)
-	unsigned int secs;
+alarm(unsigned int secs)
 {
 	struct itimerval it, oitv;
 	struct itimerval *itp = &it;
 
-    itp->it_interval.tv_usec = 0;
-    itp->it_interval.tv_sec = 0;
+	timerclear(&itp->it_interval);
 	itp->it_value.tv_sec = secs;
 	itp->it_value.tv_usec = 0;
 	if (setitimer(ITIMER_REAL, itp, &oitv) < 0)
-#if 1 /* BIONIC: Same behaviour than GLibc for errors */
-		return 0;
-#else
-		return (-1);
-#endif
+		return ((unsigned int) -1);
 	if (oitv.it_value.tv_usec)
 		oitv.it_value.tv_sec++;
 	return (oitv.it_value.tv_sec);
diff --git a/tests/unistd_test.cpp b/tests/unistd_test.cpp
index 9969d49bc..f50c102f6 100644
--- a/tests/unistd_test.cpp
+++ b/tests/unistd_test.cpp
@@ -112,3 +112,7 @@ TEST(unistd, read_EBADF) {
   ASSERT_EQ(-1, read(-1, buf, sizeof(buf)));
   ASSERT_EQ(EBADF, errno);
 }
+
+TEST(unistd, alarm) {
+  ASSERT_EQ(0U, alarm(0));
+}