From dde64e47cadbd245a99f145869eb400b68cc82e9 Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@openwrt.org>
Date: Sun, 6 Jan 2013 03:04:04 +0100
Subject: [PATCH] uloop: use clock_gettime with the monotonic clock instead of
 using gettimeofday()

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
---
 CMakeLists.txt | 12 ++++++++++++
 uloop.c        | 13 +++++++++++--
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ab82270..b756247 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,4 +1,6 @@
 cmake_minimum_required(VERSION 2.6)
+INCLUDE(CheckLibraryExists)
+INCLUDE(CheckFunctionExists)
 
 PROJECT(ubox C)
 ADD_DEFINITIONS(-Os -Wall -Werror --std=gnu99 -g3 -Wmissing-declarations)
@@ -14,6 +16,16 @@ SET(SOURCES avl.c avl-cmp.c blob.c blobmsg.c uloop.c usock.c ustream.c ustream-f
 
 ADD_LIBRARY(ubox SHARED ${SOURCES})
 
+SET(LIBS)
+CHECK_FUNCTION_EXISTS(clock_gettime HAVE_GETTIME)
+IF(NOT HAVE_GETTIME)
+	CHECK_LIBRARY_EXISTS(rt clock_gettime "" NEED_GETTIME)
+	IF(NEED_GETTIME)
+		TARGET_LINK_LIBRARIES(ubox rt)
+	ENDIF()
+ENDIF()
+
+
 SET(CMAKE_INSTALL_PREFIX /usr)
 
 FILE(GLOB headers *.h)
diff --git a/uloop.c b/uloop.c
index ecf26ec..2de4feb 100644
--- a/uloop.c
+++ b/uloop.c
@@ -351,6 +351,15 @@ int uloop_timeout_add(struct uloop_timeout *timeout)
 	return 0;
 }
 
+static void uloop_gettime(struct timeval *tv)
+{
+	struct timespec ts;
+
+	clock_gettime(CLOCK_MONOTONIC, &ts);
+	tv->tv_sec = ts.tv_sec;
+	tv->tv_usec = ts.tv_nsec / 1000;
+}
+
 int uloop_timeout_set(struct uloop_timeout *timeout, int msecs)
 {
 	struct timeval *time = &timeout->time;
@@ -358,7 +367,7 @@ int uloop_timeout_set(struct uloop_timeout *timeout, int msecs)
 	if (timeout->pending)
 		uloop_timeout_cancel(timeout);
 
-	gettimeofday(&timeout->time, NULL);
+	uloop_gettime(&timeout->time);
 
 	time->tv_sec += msecs / 1000;
 	time->tv_usec += (msecs % 1000) * 1000;
@@ -521,7 +530,7 @@ void uloop_run(void)
 	uloop_setup_signals();
 	while(!uloop_cancelled)
 	{
-		gettimeofday(&tv, NULL);
+		uloop_gettime(&tv);
 		uloop_process_timeouts(&tv);
 		if (uloop_cancelled)
 			break;