$Id: NOTES.txt,v 1.4.2.1 2003/03/28 05:25:57 bko Exp $ Technical information and notes on the SIP stack. Known issues 1. Quoted strings are not translated to users that is, users are expected to pass quoted values to the system, e.g. SipFrom from; // note -- the next line is enough quotation to form the // literal string \"SecondQuote\" from.setDisplayName("\\\"SecondQuote\\\""); will produce the text From: \"SecondQuote\" on encoding as the display-name. this is in opposition to an "idealized" system where the need to quote would be caught automatically, and this would work: // note -- the next line is enough quotation to form the // literal string "SecondQuote" -- note there is no '\' // character explicitly added to the text here. from.setDisplayName("\"SecondQuote\""); producing the text From: \"SecondQuote\" as the display name, but, when the user gets the display name for printing, or something, they get "SecondQuote" without having to match the \'s. this isn't entirely needed, but it sure might be nice. It is, however, needed for translating quoted URLs, e.g. sip:4000@abc.com being equal to sip:4000@%41%42%43.com How To Add A New Header In order to add a new header, you will have to take a few steps: 1. You must create a new class, which derives publicly from SipHeader (see SipHeader.hxx). 2. You need to add a new SipHeaderType for the message. See SipHeader.hxx for where this should be done. Add this in alphabetical order, or you will have a lot of trouble later. Make sure that SIP_UNKNOWN_HDR is last -- sipHeaderNameCount, which sizes these arrays, is equal to SIP_UNKNOWN_HDR + 1. 3. You need to add an entry to the sipHeaderTable in SipHeader.cxx . This is also in alphabetical order. The entry you add needs to be in the exact same place as the entry in SipHeaderType. The sipHeaderTable is used to populate the sipHeaderNames table, which is used to determine which type a given sipHeader is. 4. Fill out decodeHeader so that a new sipHeader can get constructed based on a SipHeaderType. If you have a new header named NewHeader, with SipHeaderType SIP_NEW_HEADER_HDR, and class SipNewHeader, for the text NewHeader: content of the new header the function decodeHeader will be passed decodeHeader( SIP_NEW_HEADER_HDR, Data("content of the new header") ); and will expect back a new SipNewHeader object allocated on the heap. 5. *IMPORTANT* You also need to fill out the sipHeaderOutputOrder struct in SipRawHeaderContainer.cxx. If you do not fill this out, your header will never be printed. This header specifies the order in which the headers will be output when encode() is called. The headers which appear first in the sipHeaderOutputOrder will appear first, while later ones will appear later. note that sipHeaderOutputOrder must contain all of the headers to be output -- if the header does not appear in this struct, it will not be encoded. ====================================================================== Copyright 2000-2003, Cisco Systems, Inc. THE INFORMATION HEREIN IS PROVIDED ON AN "AS IS" BASIS, WITHOUT ANY WARRANTIES OR REPRESENTATIONS, EXPRESS, IMPLIED OR STATUTORY, INCLUDING WITHOUT LIMITATION, WARRANTIES OF NONINFRINGEMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. $Id: NOTES.txt,v 1.4.2.1 2003/03/28 05:25:57 bko Exp $
