iterate topoogy header related stuff

[oweals/gnunet.git] / src / include / gnunet_time_lib.h

diff --git a/src/include/gnunet_time_lib.h b/src/include/gnunet_time_lib.h
index fa443a4632cff80a6914f0fd7c1a987928e5a8d4..aa4e8d5db745dfade311145b5b596586fea5a645 100644 (file)
--- a/src/include/gnunet_time_lib.h
+++ b/src/include/gnunet_time_lib.h
@@ -314,6 +314,22 @@ struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_add (struct
                                                       GNUNET_TIME_Relative
                                                       duration);
 
+
+/**
+ * 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);
+
 /**
  * Multiply relative time by a given factor.
  *
@@ -353,6 +369,17 @@ struct GNUNET_TIME_Relative GNUNET_TIME_relative_add (struct
                                                       GNUNET_TIME_Relative
                                                       a2);
 
+/**
+ * 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);
+
 
 /**
  * Convert relative time to network byte order.