mod_auth-any/6075: Give more accurate error message when dbm files cannot be opened.

[Seth Chaiklin <se...@psy.au.dk>]

>Number:         6075
>Category:       mod_auth-any
>Synopsis:       Give more accurate error message when dbm files cannot be opened.
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Class:          change-request
>Submitter-Id:   apache
>Arrival-Date:   Sat May 13 16:20:00 PDT 2000
>Closed-Date:
>Last-Modified:
>Originator:     seth@psy.au.dk
>Release:        1.3.12
>Organization:
apache
>Environment:
Linux 
>Description:
If you search on "could not open dbm auth file" in the bugs database, then
you will see, from time to time, over the past two  years that people
report that things were working, and then suddenly they got an error
message about could not open dbm auth file.

I recently had the same experience, and after a while discovered that
apache was being compiled with -lndbm (because I have glibc-2.1.2),
but my databases had been made with gdbm.  (So after recompiling with
gdbm (where I hacked helpers/find-dbm-lib), everything worked just fine.

My suggestion:  Perhaps the (2)No such file or directory message should
not appear, at least in the cases where the file is actually there.
It would probably help a number of people to debug this problem (given
that apache already acknowledges that its config for the libraries is
not so good).

I have not given so many details here, because presumably the person who
cares and feeds mod_auth_dbm.c knows exactly what the issue is.
If not, then I can elaborate.
>How-To-Repeat:

>Fix:
the relevant place is src/modules/standard/mod_auth_dbm.c, line 161

It is mostly a matter of having more accurate error messages.
(i.e., to check whether the file is actually there or not, and perhaps
there are more precise error messages about the problem that the
various database packages provide, instead of "could not open dbm...")


Alternatively, maybe a mention in the FAQ about the idea of checking which
database was actually compiled into apache, and checking that this is
also the format of the database that one is trying to read.
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