---- [email protected] wrote:
>
> ---- Joe Lewis <[email protected]> wrote:
> > On 6/21/12 6:46 PM, [email protected] wrote:
> > > ---- Joe Lewis<[email protected]> wrote:
> > >> On 6/21/12 5:49 PM, [email protected] wrote:
> > >>> ---- [email protected] wrote:
> > >>>> ---- Sorin Manolache<[email protected]> wrote:
> > >>>>> And I forgot to say: run gdb in some sort of environment where you see
> > >>>>> your current source code line and a couple of surrounding lines. You
> > >>>>> could achieve this with the "list" command, but I prefer running gdb
> > >>>>> in
> > >>>>> emacs and let emacs do the nice listing of source code in a different
> > >>>>> panel.
> > >>>>>
> > >>>>> S
> > >>>> Here's the function from my source. It's the original from
> > >>>> mod_headers.c, plus my printf:
> > >>>>
> > >>>>
> > >>>> static int header_post_config(apr_pool_t *pconf, apr_pool_t *plog,
> > >>>> apr_pool_t *ptemp, server_rec *s)
> > >>>> {
> > >>>> printf("In header_post_config\n");
> > >>>> header_ssl_lookup = APR_RETRIEVE_OPTIONAL_FN(ssl_var_lookup);
> > >>>> return OK;
> > >>>> }
> > >>>>
> > >>>> Jim
> > >>> Hi,
> > >>>
> > >>> I was able to get the segfault to go away. Here's what I had to do:
> > >>>
> > >>> - Created /etc/ld.so.conf.d/my.conf, and added the directory where my
> > >>> libobaccess.so was
> > >>> - Run 'ldconfig' to activate.
> > >>> - In the apxs command, DON'T include the -L and -l arguments
> > >>>
> > >>> After that, Apache appears to start ok, without segfault :)!!
> > >>>
> > >>> Thanks for all of the great help, esp. the suggestion about checking
> > >>> "ldconfig -p". I still don't understand why, but I'm just glad that I
> > >>> can get past this piece so now I can debug my module :)...
> > >>>
> > >>> Later,
> > >>> Jim
> > >> I'm just glad this list is as good as it is!
> > >>
> > >> FYI, the ldconfig is the dynamic linker control, and those
> > >> /etc/ld.so.conf.d files provide additional search directories for the
> > >> linker to check in when loading a library.
> > >>
> > >> Joe
> > >> --
> > >> http://www.silverhawk.net/
> > >
> > > Hi,
> > >
> > > Sorry to report, but my earlier report was a "false positive" :)...
> > >
> > > I forgot that the mod_headers.c that I was doing the earlier testing with
> > > had all references to the libobaccess.so removed :(!!
> > >
> > > So, I'm still stuck with basically the same problem, now, working with my
> > > "full" code, with the calls in it:
> > >
> > > - If I compile with -L and -l, Apache segfaults when it starts
> > >
> > > - If I compile without -L and -l, then I get "undefined symbol" errors
> > > when I try to start Apache, e.g.:
> > >
> > > [root@apachemodule build-mod_headers]# /apps/httpd2222/bin/apachectl -k
> > > start -X
> > > httpd: Syntax error on line 84 of /apps/httpd2222/conf/httpd.conf: Cannot
> > > load /apps/httpd2222/modules/mod_headers.so into server:
> > > /apps/httpd2222/modules/mod_headers.so: undefined symbol:
> > > ObResource_isProtected
> > >
> > > That "ObResource_isProtected" should be a symbol in libobaccess.so, and
> > > in fact, if I do "nm --dynamic", I get:
> > >
> > > [root@apachemodule build-mod_headers]# nm --dynamic
> > > /apps/netpoint/lib64/libobaccess.so | grep "ObResource_isProtected"
> > > 00000000000a6d80 T ObResource_isProtected
> > > [root@apachemodule build-mod_headers]#
> > >
> > >
> > > I'm *assuming* that the reason for the "undefined symbol" error is that
> > > libobaccess.so is actually not being loaded, but then when I try to load
> > > libobaccess.so, either via -L and -l in the apxs, or using LoadFile in
> > > httpd.conf, I get the segfault (same gdb info, BTW).
> > >
> > > Catch-22?
> > >
> > > Sorry for the false alarm :(!!
> > >
> > > Jim
> > >
> > >
> > Not a catch-22. The -L and -l specify linker options when assembling
> > the code. The ldconfig is a run-time thing. If you are getting the
> > stderr messages, you are making it all the way into your library. I'd
> > suggest commenting out the following line and see if you get farther :
> >
> > header_ssl_lookup = APR_RETRIEVE_OPTIONAL_FN(ssl_var_lookup);
> >
> > That should tell you if the problem is the ssl_var_lookup.
> >
> > Joe
> > --
> > http://www.silverhawk.net/
>
>
> Hi,
>
> Thanks for the suggestion. I just tried what you suggested, and got a
> segfault when I started Apache with the modified module.
>
> Jim
>
>
Hi,
As a reminder, here's the gdb with the library loaded:
(gdb) b header_post_config
Function "header_post_config" not defined.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 1 (header_post_config) pending.
(gdb) run -d /apps/httpd2222/ -f /apps/httpd2222/conf/httpd.conf
Starting program: /apps/httpd2222/bin/httpd -d /apps/httpd2222/ -f
/apps/httpd2222/conf/httpd.conf
[Thread debugging using libthread_db enabled]
[New Thread 182897610272 (LWP 11317)]
Breakpoint 2 at 0x2a9751ea90: file mod_headers.c, line 1121.
Pending breakpoint "header_post_config" resolved
mod_headers-jl V0.09 - start calling OAM API
In register_hooks
In create_headers_dir_config
In create_headers_dir_config
In header_cmd
In header_inout_cmd
In parse_format_tag
In parse_misc_string
In create_headers_dir_config
In header_cmd
In header_inout_cmd
In parse_format_tag
In parse_misc_string
[Switching to Thread 182897610272 (LWP 11317)]
Breakpoint 2, header_post_config (pconf=0x573138, plog=0x5a52c8,
ptemp=0x5a72d8, s=0x59d3a8) at mod_headers.c:1121
1121 printf("In header_post_config\n");
(gdb) n
1120 {
(gdb) n
1121 printf("In header_post_config\n");
(gdb) n
In header_post_config
1122 header_ssl_lookup = APR_RETRIEVE_OPTIONAL_FN(ssl_var_lookup);
(gdb) n
1124 }
(gdb) n
0x00000000004360c7 in ap_run_post_config (pconf=0x573138, plog=0x5a52c8,
ptemp=0x5a72d8, s=0x59d3a8) at config.c:91
91 AP_IMPLEMENT_HOOK_RUN_ALL(int, post_config,
(gdb) n
Program received signal SIGSEGV, Segmentation fault.
0x0000003518d6c1e1 in BN_num_bits () from /lib64/libcrypto.so.4
So, it's actually blowing up in "BN_num_bits()" in /lib64/libcrypto.so.4?
Jim
