Building and Debugging PHPMapScript on Linux
Stephen Woodbridge wrote:
> I have finally gotten around to trying to debug the > PHP3/Mapscript? problem I was having. You said I should > build PHP/Mapscript? as a static php CGI executable so I > can run it in gdb.
Actually, I meant compile PHP as a CGI executable instead of as an Apache DSO. And then you still compile PHP MapScript the same way, as a php_mapscript.so file that will be loaded by PHP at runtime.
Once you're all setup, you can debug a PHP script that crashes using the 'php' CGI executable in gdb with:
$ gdb ./php ... (gdb) run /path/to/test.php ...
Here is the fun part: If you need to setup a breakpoint inside php_mapscript.so then you have to:
- First set a breakpoint in php_dl()
- start the program, when it reaches php_dl(), type "finish" to let php_dl() finish its execution
- debugger will stop again at the end of php_dl(), after php_mapscript.so is loaded... then you can set breakpoints anywhere in php_mapscript.so and enjoy gdb! :)
- Make sure you disable all breakpoints before re-running the program or gdb will keep complaining about them
There may be ways to automate this in gdb but I never looked into that any further... I welcome suggestions.
> All the documentation only talks about building it as a DSO module for > apache. Can you send me a link or have someone add it to Wiki? I think > this would be a great help to aid others that might want to work with > PHP3 and Mapscript. >
The answer to this question has been moved to a separate PHPMapScriptCGI page.
> Also have you guys posted documentation on how to build Mapscript for > PHP4 and !MapServer 3.5? on Wiki? >
Nothing special to say there... MapServer's configure takes care of it all on most platforms... here are some detailed steps (hopefully I didn't forget anything):
- Compile and install PHP as a CGI as described above
- Run configure in your mapserver dir. with the --with-php switch:
./configure --with-php=/path/to/php-src-that-you-just-compiled ...
- run 'make', that will automagically build mapserv, etc. ... and php_mapscript.so in mapserver/mapscript/php3
- Edit your php.ini and make sure extensions_dir is set to point to a valid location (e.g. /usr/local/lib/php4)
- Copy php_mapscript.so to your extensions_dir
- Make sure all libs used in your MapServer build are included in your runtime library path. See the PHP MapScript install FAQ about this common problem: http://www.mapserver.org/installation/php.html#faq-common-problems
- You're ready to use dl("php_mapscript.so"); to load and use PHP MapScript in your PHP apps.
Go back to: PHPMapScript