From 71846a3ea365e3fdc749716d515237af4588fb30 Mon Sep 17 00:00:00 2001
From: stansmith <stansmith@ad392aa1-c5ef-ae45-8dd8-e69d62a5ef86>
Date: Thu, 9 Jul 2009 17:56:49 +0000
Subject: [PATCH] [ETC] Provide a common implementation for gettimeofday().

git-svn-id: svn://openib.tc.cornell.edu/gen1@2280 ad392aa1-c5ef-ae45-8dd8-e69d62a5ef86
---
 trunk/etc/user/gtod.c           | 111 ++++++++++++++++++++++++++++++++
 trunk/inc/user/linux/sys/time.h |  14 ++++
 2 files changed, 125 insertions(+)
 create mode 100644 trunk/etc/user/gtod.c
 create mode 100644 trunk/inc/user/linux/sys/time.h

diff --git a/trunk/etc/user/gtod.c b/trunk/etc/user/gtod.c
new file mode 100644
index 00000000..5207a268
--- /dev/null
+++ b/trunk/etc/user/gtod.c
@@ -0,0 +1,111 @@
+#ifndef _GTOD_C_
+#define _GTOD_C_
+
+/*
+ * int gettimeofday(struct timeval *ptv, void *ignored)
+ */
+
+#include <windows.h>
+#include <winsock2.h>
+
+
+static __inline
+void FileTimeToTimeval(LPFILETIME pft, struct timeval * ptv)
+{ /* Note that LONGLONG is a 64-bit value */
+	LONGLONG ll;
+
+	if(!pft || !ptv) {
+		ptv->tv_sec = 0;
+		ptv->tv_usec = 0;
+		return;
+	}
+
+	ll = ((LONGLONG) pft->dwHighDateTime << 32);
+	ll += (LONGLONG) pft->dwLowDateTime;
+	ll -= 116444736000000000;
+
+	ptv->tv_sec = (long) (ll / 10000000);
+	ptv->tv_usec = (long) (ll - ((LONGLONG)(ptv->tv_sec) * 10000000)) / 10;
+}
+
+
+// static __inline
+int gettimeofday(struct timeval *ptv, void *ignored)
+{
+	static int QueryCounter = 2;
+	FILETIME CurrentTime;
+	UNREFERENCED_PARAMETER(ignored);     
+
+	if(!ptv) return -1;
+
+	if(QueryCounter)
+	{
+		static LARGE_INTEGER Frequency;
+		static LARGE_INTEGER Offset; /* counter offset for right time*/
+		static LARGE_INTEGER LastCounter;
+		LARGE_INTEGER Time;
+		LARGE_INTEGER Counter;
+	
+		GetSystemTimeAsFileTime(&CurrentTime);
+		QueryPerformanceCounter(&Counter);
+	
+		if(QueryCounter == 2)
+		{
+			QueryCounter = 1;
+			if(!QueryPerformanceFrequency(&Frequency))
+			{
+				QueryCounter = 0;
+				Frequency.QuadPart = 10000000; /* prevent division by 0 */
+			}
+	
+			/* get time as a large integer */
+			Counter.HighPart &= 0x7FL; /* Clear high bits to prevent overflow */
+			Offset.LowPart = CurrentTime.dwLowDateTime;
+			Offset.HighPart = (LONG) CurrentTime.dwHighDateTime;
+			Offset.QuadPart -= Counter.QuadPart * 10000000 / Frequency.QuadPart;
+		}
+	
+		/* Convert counter to a 100 nanoseconds resolution timer value. */
+	
+		Counter.HighPart &= 0x7FL; /* Clear high bits to prevent overflows */
+		Counter.QuadPart *= 10000000; /* need time stamp in 100 ns units */
+		Counter.QuadPart /= Frequency.QuadPart;/* counter of 0.1 microseconds */
+	
+		if(LastCounter.QuadPart > Counter.QuadPart)
+		{ /* Counter value wrapped */
+			Offset.QuadPart += (0x7F00000000*10000000) / Frequency.QuadPart;
+		}
+		LastCounter = Counter;
+	
+		/* Add the in previous call calculated offset */
+		Counter.QuadPart += Offset.QuadPart;
+	
+		/* get time as a large integer */
+		Time.LowPart = CurrentTime.dwLowDateTime;
+		Time.HighPart = (LONG) CurrentTime.dwHighDateTime;
+	
+		/* keep time difference within an interval of +- 0.1 seconds
+		relative to the time function by adjusting the counters offset */
+	
+		if( ((Time.QuadPart + 1000000) < Counter.QuadPart) ||
+				((Time.QuadPart - 1000000) > Counter.QuadPart) )
+		{ /* Adjust the offset */
+			Offset.QuadPart += Time.QuadPart - Counter.QuadPart;
+			Counter.QuadPart = Time.QuadPart;
+		}
+	
+		/* use the adjusted performance counter time for the time stamp */
+		CurrentTime.dwLowDateTime = Counter.LowPart;
+		CurrentTime.dwHighDateTime = Counter.HighPart;
+	}
+	else
+	{
+		GetSystemTimeAsFileTime(&CurrentTime);
+	}
+
+	FileTimeToTimeval(&CurrentTime,ptv);
+
+	return(0);
+}
+
+#endif /* _GTOD_C_ */
diff --git a/trunk/inc/user/linux/sys/time.h b/trunk/inc/user/linux/sys/time.h
new file mode 100644
index 00000000..50ba78eb
--- /dev/null
+++ b/trunk/inc/user/linux/sys/time.h
@@ -0,0 +1,14 @@
+#ifndef _SYS_TIME_H_
+#define _SYS_TIME_H_
+
+#include <winsock2.h>
+
+struct timezone {
+        int     tz_minuteswest; /* minutes west of Greenwich */
+        int     tz_dsttime;     /* type of dst correction */
+};
+
+
+extern int gettimeofday(struct timeval *ptv, void *ignored);
+
+#endif
-- 
2.41.0