added [feature#14] EventTimeStamp decoding from ReadPropertyMultiple app (#496)

Co-authored-by: Steve Karg <skarg@users.sourceforge.net>

CHANGELOG.md

@@ -18,6 +18,8 @@ The git repositories are hosted at the following sites:
 
 ### Added
 
+Added [feature#14] EventTimeStamp decoding from ReadPropertyMultiple app
+
 ### Changed
 
 ### Fixed

src/bacnet/bacapp.c

@@ -896,6 +896,27 @@ BACNET_APPLICATION_TAG bacapp_context_tag_type(
                     break;
             }
             break;
+        case PROP_EVENT_TIME_STAMPS:
+            /*  BACnetTimeStamp ::= CHOICE {
+                    time [0] Time, -- deprecated in version 1 revision 21
+                    sequence-number [1] Unsigned (0..65535),
+                    datetime [2] BACnetDateTime
+                } 
+            */
+            switch (tag_number) {
+                case TIME_STAMP_TIME:
+                    tag = BACNET_APPLICATION_TAG_TIMESTAMP;
+                    break;
+                case TIME_STAMP_SEQUENCE:
+                    tag = BACNET_APPLICATION_TAG_UNSIGNED_INT;
+                    break;
+                case TIME_STAMP_DATETIME:
+                    tag = BACNET_APPLICATION_TAG_DATETIME;
+                    break;
+                default:
+                    break;
+            }
+            break;
         default:
             break;
     }

src/bacnet/timestamp.c

@@ -105,7 +105,14 @@ void bacapp_timestamp_copy(BACNET_TIMESTAMP *dest, BACNET_TIMESTAMP *src)
     }
 }
 
-/** Encode a time stamp.
+/** 
+ * @brief Encode a time stamp.
+ *  
+ *  BACnetTimeStamp ::= CHOICE {
+ *      time [0] Time, -- deprecated in version 1 revision 21
+ *      sequence-number [1] Unsigned (0..65535),
+ *      datetime [2] BACnetDateTime
+ *  }
  *
  * @param apdu  Pointer to the APDU buffer.
  * @param value  Pointer to the variable that holds
@@ -179,6 +186,13 @@ int bacapp_encode_context_timestamp(
 
 /**
  * @brief Decode a time stamp from the given buffer.
+ *  
+ *  BACnetTimeStamp ::= CHOICE {
+ *      time [0] Time, -- deprecated in version 1 revision 21
+ *      sequence-number [1] Unsigned (0..65535),
+ *      datetime [2] BACnetDateTime
+ *  }
+ *
  * @param apdu  Pointer to the APDU buffer.
  * @param apdu_size - the APDU buffer length
  * @param value  Pointer to the variable that shall