os-hpux/6104: Apache regcomp()/regexec() collision with libc

[Chris Beauregard <ch...@ec.gc.ca>]

>Number:         6104
>Category:       os-hpux
>Synopsis:       Apache regcomp()/regexec() collision with libc
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Fri May 19 12:00:01 PDT 2000
>Closed-Date:
>Last-Modified:
>Originator:     chris.beauregard@ec.gc.ca
>Release:        1.3.9
>Organization:
apache
>Environment:
HP-UX metweb0 B.11.00 U 9000/800 2008361008 unlimited-user license
gcc version 2.95.2 19991024 (release)
>Description:
I spent about a week trying to track this one down...

The regcomp in apache overrides the libc version. This is fine, but when my
mod_perl module loads in a shared library that uses regcomp/regexec, things
get weird. Deep down in the chain of libraries, I do:
	regcomp(preg,workbuf,REG_EXTENDED|REG_ICASE|REG_NOSUB)
which calls the Apache version. This is fine, except that after running
though cpp, it looks like
	regcomp(preg,workbuf,1|4|8),
which, to the Apache version, means
	regcomp(preg,workbuf,REG_EXTENDED|REG_NOSUB)

This sucks for those of us expecting REG_ICASE to actually work.

I checked the 2.0a3 source and the regex stuff is about the same, so the bug
will likely be there as well.
>How-To-Repeat:
Basically, you need to create a shared library that is compiled outside of the
Apache/mod_perl/perl family and link to it from, say, an Apache module.
Any kind of regcomp() that uses ICASE will then be bogus.
>Fix:
Renaming the Apache regex stuff to avoid the name clash would be optimal.

A cheaper fix would be to just change the values of the REG_* macros, but since,
for example, Linux uses 0x2 for REG_ICASE, this would break other platforms.

To (hack, hack) fix our code, I just added a REG_NEWLINE (which has a value of
2), since I don't care about newline expansion.

It's possible that linking libc to the original shared library would work, but
I have quite a number of shared libs that user regex calls, so it would be major
bloat.
>Release-Note:
>Audit-Trail:
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