RE: slapd and dynamic modules

["Howard Chu" <hyc@highlandsun.com>]

Another approach here is to merge slapadd/slapcat/slapindex into the main
slapd binary and just differentiate based on argv[0] and commandline args.
Any objections?

  -- 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 Howard Chu
> Sent: Tuesday, January 20, 2004 11:30 PM

> Well, this problem first reared its head with Windows and I
> ignored it, but
> it's also an issue on z/OS and some AIX releases as well - on these
> platforms, not only do shared objects need to have symbol
> references fully
> resolved at build time, but the name of the file that
> provides the symbols is
> also embedded by the linker, and only that named file is
> allowed to resolve
> the symbols at runtime. This is in contrast to SysV-derived
> dynamic linkers,
> which record the file dependencies but allow a symbol to be
> resolved by the
> first module the runtime linker sees, regardless of whether
> it was the same
> file that was originally linked at build time.
>
> What this means to us is that on these platforms, plugins,
> overlays, modules,
> and dynamic backends all must be linked against the slapd
> binary, and that
> they generally will not behave correctly when loaded by the
> slapadd/slapcat/slap* tools. If they are implicitly linked
> against slapd (as
> our current build environment is set up) then when e.g.
> slapadd loads a
> module, that module will implicitly bring in a copy of the
> slapd binary. And
> when the module calls a function to register itself (like
> backend_init or
> overlay_register) it will do so in the address space of the
> slapd image. When
> slapadd gets to a point that tries to invoke code from that
> module, (e.g.,
> "backend bdb") it will fail, because the module isn't
> registered in slapadd's
> address space.