directory-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From directory-...@incubator.apache.org
Subject [Apache Directory Project Wiki] Updated: TLVPageInfo
Date Sat, 19 Feb 2005 21:03:17 GMT
   Date: 2005-02-19T13:03:17
   Editor: EmmanuelLecharny
   Wiki: Apache Directory Project Wiki
   Page: TLVPageInfo
   URL: http://wiki.apache.org/directory/TLVPageInfo

   no comment

Change Log:

------------------------------------------------------------------------------
@@ -89,7 +89,7 @@
 Those '''Value''' are terminal. They can't contain another TLV. In the sample, we have 4
primitive '''Values''' :
  * 02 01 01 which is an ''Integer'' representing the Message ID #1
  * 0A 01 00 which is an ''ENUMERATED'' which value is 0 (success for a BindResponse LDAP
Message)
- * 04 00 are OCTET STRING with no value, as the ''Length'' is 0.
+ * the last two 04 00 are OCTET STRINGs with no value, as the ''Length'' is 0.
 
 We can see that even if we can read a '''TLV''', the semantic is carried by the upper layer.
'''TLV''' are just structured containers, no more.
 
@@ -98,6 +98,9 @@
 The last point is that a primitive value has a fixed size, given by the '''Lengh''' part
of the '''TLV'''. It will be used for ''constructed values''.
 
 ==== Constructed Value ====
+Constructed values are '''TLV''' with inner '''TLVs''' in its '''Value'''. It ha a '''Length'''
which is the sum of all its inner '''TLVs'''. A bit is set in the '''Tag''' to distinguish
a ''Constructed value'' from a ''Primitive value'' : the 5th bit of the first tag's byte.
In the sample, the first '''TLV''' tag is ''30'', which can be read 00__'''1'''__1-0000 binary.
The 5th bit (bold) is set : it's a ''constructed value''.
+
+
 (TODO : replace the total BS below ...)
 
 What about the '''Values'''? '''Length''' was easy, it was totally context-free. Which kind
of '''Value''' can we have? How do we know the type of each '''Value'''?

Mime
View raw message