general/4884: "LoadFile foo.so" loads foo.so twice from different directories

[Peter Davis <pe...@born.com>]

>Number:         4884
>Category:       general
>Synopsis:       "LoadFile  foo.so"  loads foo.so twice from different directories
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    apache
>State:          open
>Class:          support
>Submitter-Id:   apache
>Arrival-Date:   Fri Aug 20 15:10:02 PDT 1999
>Last-Modified:
>Originator:     peter.davis@born.com
>Organization:
apache
>Release:        1.3.3, 1.3.6
>Environment:
SunOS malt 5.5.1 Generic_103640-24 sun4u sparc SUNW,Ultra-2

software built with Sun WorkShop Compiler C++ 4.2
>Description:
I'm attempting the following on an Apache 1.3.x server running on Solaris
2.5.1:

I have 3 shared objects;  foo.so, bar.so, blah.so.  blah.so is built as a
module and will be loaded using "LoadModule."  blah.so uses API calls into
foo.so, which in turn uses API calls into bar.so;  bar.so will ultimately
open a socket to another application.   My httpd.conf file looks like...

...
LoadFile    /usr/lib/libC.so.5        // needed by bar.so
LoadFile    libexec/foo.so
LoadModule  blah_module  libexec/blah.so
...
ClearModuleList
...
AddModule mod_blah.c

There is no need to "LoadFile bar.so", as foo.so uses dlopen() to access the
API routines.

foo.so does a couple things on startup, in its #pragma init routine:
- spits a message about where it's executing, using the output of getcwd()
- reads a configuration file from the current directory, and dumps the
parameters
- spawns a thread that will periodically reread the configuration file
- dlopen()'s bar.so, which in turn reads a config file and establishes its
socket

The behavior is as follows:
- the stdout line after "apachectl start" displays messages from foo.so;
'running in $ServerRoot/bin' (or sbin)
- the configuration file is read and messages displayed, including success
messages from bar.so
- stdout says apache is up and running

- the apache error log, $ServerRoot/logs/error_log  (or var/logs/error_log)
displays messages from foo.so saying 'running in "/" '
- the error log continues with messages from foo.so about not being able to
read the config file (it can't, from "/") and lists using default parameters
- the error log continues with error messages from bar.so, since it can't
read its config file, either;  no socket is established, since the port
address is in bar's config file.

It appears that Apache is loading the libraries twice, the second time in a
directory they're not expecting.

If I change foo.so and config files to chdir() to the "correct" location (to load bar.so and pick up its config file), I get multiple sets of socket connections.  The behavior is as if foo.so got unloaded and reloaded, but bar.so was never unloaded (in particular, it's sockets were never released.)


>How-To-Repeat:

>Fix:

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