stuff

[oweals/gnunet.git] / src / util / time.c

diff --git a/src/util/time.c b/src/util/time.c
index 36a3c8631df2dc1a7bbf1083f7bb4b7991be9a9d..3d53e0af2f8a36809610eb484db09380af3c3f95 100644 (file)
--- a/src/util/time.c
+++ b/src/util/time.c
@@ -137,6 +137,22 @@ GNUNET_TIME_relative_min (struct
 }
 
 
+/**
+ * Return the maximum of two relative time values.
+ *
+ * @param t1 first timestamp
+ * @param t2 other timestamp
+ * @return timestamp that is larger
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_max (struct
+                          GNUNET_TIME_Relative
+                          t1, struct GNUNET_TIME_Relative t2)
+{
+  return (t1.value > t2.value) ? t1 : t2;
+}
+
+
 
 /**
  * Return the minimum of two relative time values.
@@ -254,6 +270,33 @@ GNUNET_TIME_absolute_add (struct GNUNET_TIME_Absolute start,
   return ret;
 }
 
+
+/**
+ * Subtract a given relative duration from the
+ * given start time.
+ *
+ * @param start some absolute time
+ * @param duration some relative time to subtract
+ * @return ZERO if start <= duration, or FOREVER if start time is FOREVER; start-duration otherwise
+ */
+struct GNUNET_TIME_Absolute 
+GNUNET_TIME_absolute_subtract (struct
+                              GNUNET_TIME_Absolute
+                              start,
+                              struct
+                              GNUNET_TIME_Relative
+                              duration)
+{
+  struct GNUNET_TIME_Absolute ret;
+  if (start.value <= duration.value)
+    return GNUNET_TIME_UNIT_ZERO_ABS;
+  if (start.value == GNUNET_TIME_UNIT_FOREVER_ABS.value)
+    return GNUNET_TIME_UNIT_FOREVER_ABS;
+  ret.value = start.value - duration.value;
+  return ret;
+}
+
+
 /**
  * Multiply relative time by a given factor.
  *
@@ -276,6 +319,26 @@ GNUNET_TIME_relative_multiply (struct GNUNET_TIME_Relative rel,
 }
 
 
+/**
+ * Divide relative time by a given factor.
+ *
+ * @param rel some duration
+ * @param factor integer to divide by
+ * @return FOREVER if rel=FOREVER or factor==0; otherwise rel/factor
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_divide (struct GNUNET_TIME_Relative rel,
+                            unsigned int factor)
+{
+  struct GNUNET_TIME_Relative ret;
+  if ( (factor == 0) ||
+       (rel.value == GNUNET_TIME_UNIT_FOREVER_REL.value) )
+    return GNUNET_TIME_UNIT_FOREVER_REL;
+  ret.value = rel.value / (unsigned long long) factor;
+  return ret;
+}
+
+
 /**
  * Calculate the estimate time of arrival/completion 
  * for an operation.
@@ -309,6 +372,8 @@ GNUNET_TIME_calculate_eta (struct GNUNET_TIME_Absolute start,
 /**
  * Add relative times together.
  *
+ * @param a1 first timestamp
+ * @param a2 second timestamp
  * @return FOREVER if either argument is FOREVER or on overflow; a1+a2 otherwise
  */
 struct GNUNET_TIME_Relative
@@ -329,8 +394,33 @@ GNUNET_TIME_relative_add (struct GNUNET_TIME_Relative a1,
 }
 
 
+/**
+ * Subtract relative timestamp from the other.
+ *
+ * @param a1 first timestamp
+ * @param a2 second timestamp
+ * @return ZERO if a2>=a1 (including both FOREVER), FOREVER if a1 is FOREVER, a1-a2 otherwise
+ */
+struct GNUNET_TIME_Relative
+GNUNET_TIME_relative_subtract (struct GNUNET_TIME_Relative a1,
+                              struct GNUNET_TIME_Relative a2)
+{
+  struct GNUNET_TIME_Relative ret;
+
+  if (a2.value >= a1.value)
+    return GNUNET_TIME_relative_get_zero ();
+  if (a1.value == (uint64_t) - 1LL) 
+    return GNUNET_TIME_relative_get_forever ();
+  ret.value = a1.value - a2.value;
+  return ret;
+}
+
+
 /**
  * Convert relative time to network byte order.
+ *
+ * @param a time to convert
+ * @return time in network byte order
  */
 struct GNUNET_TIME_RelativeNBO
 GNUNET_TIME_relative_hton (struct GNUNET_TIME_Relative a)
@@ -342,6 +432,9 @@ GNUNET_TIME_relative_hton (struct GNUNET_TIME_Relative a)
 
 /**
  * Convert relative time from network byte order.
+ *
+ * @param a time to convert
+ * @return time in host byte order
  */
 struct GNUNET_TIME_Relative
 GNUNET_TIME_relative_ntoh (struct GNUNET_TIME_RelativeNBO a)
@@ -354,6 +447,9 @@ GNUNET_TIME_relative_ntoh (struct GNUNET_TIME_RelativeNBO a)
 
 /**
  * Convert absolute time to network byte order.
+ *
+ * @param a time to convert
+ * @return time in network byte order
  */
 struct GNUNET_TIME_AbsoluteNBO
 GNUNET_TIME_absolute_hton (struct GNUNET_TIME_Absolute a)
@@ -365,6 +461,9 @@ GNUNET_TIME_absolute_hton (struct GNUNET_TIME_Absolute a)
 
 /**
  * Convert absolute time from network byte order.
+ *
+ * @param a time to convert
+ * @return time in host byte order
  */
 struct GNUNET_TIME_Absolute
 GNUNET_TIME_absolute_ntoh (struct GNUNET_TIME_AbsoluteNBO a)