[Date Prev][Date Next] [Chronological] [Thread] [Top]

Re: EBCDIC

Howard Chu wrote: 
Without a radical change to the library architecture, what you suggest is
impossible to do correctly. The old UMich code did T.61/ISO8859 translation
at the socket level too. It was also broken, because at that level you have
no knowledge of schema, so you have no way to detect that a binary value
should be passed through unmodified. That approach is not viable for
reliable, correct behavior. The approach you describe suffers the same
shortcoming. Not to mention the overhead of actually performing the
translation on all the data. No matter what model your mainframe, CPU cycles
are still expensive, and even if you could correctly translate 100% of the
time, it would be a waste.

Granted, there's no way to avoid the translation problem on the client side,
but my approach guarantees that the server works correctly and efficiently.


But it needs at least a ASCII regexp library, doesn't it?

Your approach guarantees the opposite.

  -- Howard Chu
  Chief Architect, Symas Corp.       Director, Highland Sun
  http://www.symas.com               http://highlandsun.com/hyc
  Symas: Premier OpenSource Development and Support


-----Original Message-----
From: Rozonkiewiecz, Mitchell [mailto:Mitchell.Rozonkiewiecz@ca.com]



It is possible to have LDAP run 100% EBCDIC in USS on z/OS and OS/390

You need to perform EtoA and AtoE as the data is read/written to the
TCP/IP socket.

This allows all config files, schema files, etc to stay in EBCDIC and
not have to play games to work in ASCII in an EBCDIC world.

Mitch


-----Original Message-----
From: jean-frederic clere
[mailto:jfrederic.clere@fujitsu-siemens.com]
Sent: Monday, March 03, 2003 5:30 AM
To: Howard Chu
Cc: openldap-devel@OpenLDAP.org; Martin Kraemer
Subject: Re: EBCDIC

Howard Chu wrote:

I ported OpenLDAP, OpenSSL, Berkeley DB 4.1, and part of 

Cyrus SASL to

OS/390. Aside from Cyrus, all of these packages were fully 

functional
but

OpenLDAP and OpenSSL operate with ASCII internally. In addition to 

using

IBM's libascii, I wrote stdio stubs to handle ASCII/EBCDIC 

translation
for

parsing commandline args, reading config files, and writing 

log files.
These

are the only interfaces between the software and the host OS that 

needed

work, given the presence of libascii. 

I already have OpenSSL, Berkeley DB 4.1 and a lot more libraries
prepared to use
 EBCDIC APIs. I do not think I will be able to have a special ASCII
version of
those for OpenLDAP.


A lot of what I went thru is in the FAQ-o-Matic now
http://www.openldap.org/faq/data/cache/719.html

The slapd that I built with this approach interoperates 

correctly with
any

other LDAP server or client, does not need to do character-set 

translation in

the protocol transactions, and thus has no performance degradation 

compared

to a native server. 

I am not able to locate in the CVS the modifications you
describe in the

FAQ-o-Matic. How could I get them?


If you need to build a slapd that uses EBCDIC strings in 

the protocol
layer,

you're not talking LDAP. That is not worth any further discussion 

here.

That is not what I need.


If you need to use libldap from other applications, and they're 

passing in

EBCDIC strings, you have a lot of hard work ahead of you. Since the 

client

library doesn't have ready access to the schema, you don't have an 

easy way

of identifying binary values that must be left unmodified, vs string 

values

that should be translated. 

I am afraid that what I have to do.


By the way, I am putting together a small presentation on the OS/390 

port for

the OpenLDAP Developer Day conference on March 21. Perhaps we can 

discuss

more of the issues there. 

Would be nice but I am based in Europa.


 -- Howard Chu
 Chief Architect, Symas Corp.       Director, Highland Sun
 http://www.symas.com               http://highlandsun.com/hyc
 Symas: Premier OpenSource Development and Support



-----Original Message-----
From: owner-openldap-devel@OpenLDAP.org
[mailto:owner-openldap-devel@OpenLDAP.org]On Behalf Of jean-frederic
clere
Sent: Friday, February 28, 2003 7:41 AM
To: openldap-devel@OpenLDAP.org
Subject: EBCDIC


Hi,

After a long time doing other things I am returning to port
OpenLDAP to an
EBCDIC machine.
I have done the following:
- check out the tag OPENLDAP_REL_ENG_2.
- patch build/ltmain.sh (attached).
- use libregex from Apache-1.3 and snprintf/sockaddr_ip_get

from APR (Apache 

Portable Runtime).
- use getgrnam and  initgr specific to the machine.
And now I have a slapd that starts but does nothing else has
he speaks EBCDIC.

I have to integrate OpenLDAP in an EBCDIC environment
(strings _have_ to be
EBCDIC strings). So I will convert the data in input/output
as I have to link
OpenLDAP with other API that are prepared to work that way.

The EBCDIC topic appaired last year in the dev list but I do
not know what is
the actual status of the porting.

Any comments or hints?

Cheers

Jean-frederic