From: "Ara.T.Howard" <ahoward@...>
Date: 2004-04-21T23:04:11+09:00
Subject: Re: C ext best practices

On Tue, 20 Apr 2004, Tim Hunter wrote:

> Well, I won't argue that it's "best practices" but here's what RMagick
> does. RMagick assumes that the ImageMagick library, libMagick, has already
> been installed in a separate step.
> 
> RMagick uses the standard GNU ./configure, make, make install sequence.
> The configure script (built by autoconf) handles any
> non-Ruby configuration - such as finding libMagick - and builds a custom
> Makefile, extconf.rb, and a metaconfig file for install.rb. The Makefile's
> all: target runs install.rb's config and setup steps. The Makefile's
> install: target runs install.rb's install step.
> 
> Here's RMagick's Makefile.in. This will probably make it clearer than my
> prose description. (The ./configure script also accepts a number of
> options, like --with-std-ruby, that it passes on to install.rb via
> @RUBY_CONFIG_OPTS@.)
> 
> # Path to ruby interpreter
> RUBY=@RUBY@
> 
> # Any extra options from configure script to pass to 'install.rb config'
> RUBY_CONFIG_OPTS=@RUBY_CONFIG_OPTS@
> 
> all: config.save
> 	$(RUBY) install.rb setup
> 
> install:
> 	$(RUBY) install.rb install
> 
> clean: config.save
> 	$(RUBY) install.rb clean
> 
> distclean: config.save
> 	$(RUBY) install.rb clean
> 	rm -f Makefile ext/RMagick/extconf.rb metaconfig
> 	rm -f config.status Makefile config.cache config.log
> 	rm -rf autom4te.cache
> 
> uninstall: config.save
> 	$(RUBY) uninstall.rb $(RUBY_CONFIG_OPTS)
> 
> config.save: metaconfig
> 	$(RUBY) install.rb config $(RUBY_CONFIG_OPTS)

very nice.

i guess i'm thinking more along the lines of smallish packages, and would like
avoid having site_ruby/1.8/i686/foobar.so depend on
/usr/local/lib/libfoobar.so....  (i just had a bad experience supporting some
software that required LD_RUN_PATH to manage dependancies).  it would be ideal
if 

  foobar.so

was the result of compiling

  foobar.c  # original C source
  _foobar.c # ruby binding to it

obviously this wouldn't apply to packages likely to be updated independently
(like ImageMagick) but might be o.k. for smallish things like cdb, lockfile
utils, etc.

thoughts?

-a
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