Hi Matthieu, Thanks for your inquiry.
Someone from our group will contact you with either answers or more questions for clarification. Regards, Sebastian Canevari Support Escalation Engineer, US-CSS DSC PROTOCOL TEAM 7100 N Hwy 161, Irving, TX - 75039 "Las Colinas - LC2" Tel: +1 469 775 7849 e-mail: [EMAIL PROTECTED] We're hiring -----Original Message----- From: Matthieu Suiche [mailto:[EMAIL PROTECTED] Sent: Thursday, August 28, 2008 6:37 PM To: Interoperability Documentation Help Cc: [EMAIL PROTECTED]; [EMAIL PROTECTED]; Stefan (metze) Metzmacher Subject: LZ77 + DIRECT2 compression MS-OXCRPC As a PFIF subcontractor, I am requesting correction assistance: In MS-OXCRPC, 3.1.7.2.1.2 is claims "2. Find the longest match in the window for the lookahead buffer." in the "Using the compression algorithm". But it looks Microsoft implementation has an unexpected behavior regarding the above line. Actually, I've implemented both decompression and compression of (LZ77+DIRECT2) algorithm and it works well. But the problem I have is my compression function doesn't return the same output has MSFT does. The routine I've implemented to find the longest match in the window for the lookahead buffer returns a longer length than MSFT implementation. My compression routine returns: string found at uncompressed_position 0x00000052 [ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ] comp[00000035] = 00BF = Metadata (len,offset) = (22, 00000017) - uncomp_pos: 00000052 bestlen < 25 comp[00000037] = 0C (shared byte) Comparaison of the compressed chunk: comp_chunk_by_microsoft[00000035] 32 != BF mycomp[00000035] comp_chunk_by_microsoft[00000036] 00 == 00 mycomp[00000036] comp_chunk_by_microsoft[00000037] 07 != DC mycomp[00000037] As you can see, MSFT implementation encode a 0x0032 metadata at offset 0x35 which means size of 5 (2 + 3) at position -6, and my implementation encode a three bytes metadata at offset 0x35. Here, http://www.msuiche.net/samba/debug_lzxpress.zip, you can found debug outputs and concerned file. All files concern only one chunk. Could you please describe the exact process to retrieve the longest match in the window for the lookahead buffer? Regards, -- Matthieu Suiche _______________________________________________ cifs-protocol mailing list [email protected] https://lists.samba.org/mailman/listinfo/cifs-protocol
