1 files changed, 56 insertions, 0 deletions
diff --git a/timecalc.c b/timecalc.c
new file mode 100644
index 0000000..cee4e80
--- /dev/null
+++ b/timecalc.c
@@ -0,0 +1,56 @@
+/*
+
+  (C) 2011 Mika Ilmaranta
+
+*/
+
+#include <syslog.h>
+
+#include "defs.h"
+#include "timecalc.h"
+
+int timeval_diff_cmp(struct timeval *a, struct timeval *b, int operation, time_t sec, suseconds_t usec) {
+	time_t diff_sec;
+	suseconds_t diff_usec;
+
+	diff_sec = a->tv_sec - b->tv_sec;
+	diff_usec = a->tv_usec - b->tv_usec;
+
+	if(diff_usec < 0) {
+		diff_sec--;
+		diff_usec = 1000000L + diff_usec;
+	}
+
+	switch(operation) {
+	case TIMEVAL_DIFF_CMP_GT:
+		if(diff_sec > sec) return(TRUE);
+		if(diff_sec == sec && diff_usec > usec) return(TRUE);
+		return(FALSE);
+		break;
+	case TIMEVAL_DIFF_CMP_LT:
+		if(diff_sec < sec) return(TRUE);
+		if(diff_sec == sec && diff_usec < usec) return(TRUE);
+		return(FALSE);
+		break;
+	default:
+		syslog(LOG_ERR, "%s: %s: warning: unknown timeval_diff_cmp operation requested %d", __FILE__, __FUNCTION__, operation);
+		return(FALSE);
+	}
+}
+
+long timeval_diff(struct timeval *a, struct timeval *b)
+{
+	return( ((a->tv_sec - b->tv_sec) * 1000000L) + (a->tv_usec - b->tv_usec) );
+}
+
+void timeval_add(struct timeval *a, time_t sec, suseconds_t usec)
+{
+	a->tv_sec += sec;
+	a->tv_usec += usec;
+	if(a->tv_usec >= 1000000L) {
+		a->tv_sec++;
+		a->tv_usec -= 1000000L;
+	}
+}
+
+/* EOF */