1 files changed, 82 insertions, 0 deletions
diff --git a/src/helper/time_support.c b/src/helper/time_support.c
new file mode 100644
index 00000000..5a7869d9
--- /dev/null
+++ b/src/helper/time_support.c
@@ -0,0 +1,82 @@
+/***************************************************************************
+ *   Copyright (C) 2006 by Dominic Rath                                    *
+ *   Dominic.Rath@gmx.de                                                   *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program 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 General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ ***************************************************************************/
+#include "config.h"
+
+#include "time_support.h"
+
+#include <sys/time.h>
+#include <time.h>
+
+int timeval_subtract(struct timeval *result, struct timeval *x, struct timeval *y);
+int timeval_add(struct timeval *result, struct timeval *x, struct timeval *y);
+int timeval_add_time(struct timeval *result, int sec, int usec);
+
+/* calculate difference between two struct timeval values */
+int timeval_subtract(struct timeval *result, struct timeval *x, struct timeval *y)
+{
+	if (x->tv_usec < y->tv_usec)
+	{
+		int nsec = (y->tv_usec - x->tv_usec) / 1000000 + 1;
+		y->tv_usec -= 1000000 * nsec;
+		y->tv_sec += nsec;
+	}
+	if (x->tv_usec - y->tv_usec > 1000000) {
+		int nsec = (x->tv_usec - y->tv_usec) / 1000000;
+		y->tv_usec += 1000000 * nsec;
+		y->tv_sec -= nsec;
+	}
+
+	result->tv_sec = x->tv_sec - y->tv_sec;
+	result->tv_usec = x->tv_usec - y->tv_usec;
+
+	/* Return 1 if result is negative. */
+	return x->tv_sec < y->tv_sec;
+}
+
+/* add two struct timeval values */
+int timeval_add(struct timeval *result, struct timeval *x, struct timeval *y)
+{
+	result->tv_sec = x->tv_sec + y->tv_sec;
+	
+	result->tv_usec = x->tv_usec + y->tv_usec;
+	
+	while (result->tv_usec > 1000000)
+	{
+		result->tv_usec -= 1000000;
+		result->tv_sec++;
+	}
+	
+	return 0;
+}
+
+int timeval_add_time(struct timeval *result, int sec, int usec)
+{
+	result->tv_sec += sec;
+	result->tv_usec += usec;
+	
+	while (result->tv_usec > 1000000)
+	{
+		result->tv_usec -= 1000000;
+		result->tv_sec++;
+	}
+	
+	return 0;
+}
+