[cairo] Review of: [cairo-mutex] Add default implementation for CAIRO_MUTEX_INIT that uses CAIRO_MUTEX_NIL_INITIALIZER. This used to be the implementation for pthread because pthread_mutex_init() is broken. See d48bb4fbe876a93199ba48fcf5f32734fbe18ba9.

[Behdad Esfahbod]

On Mon, 2007-04-23 at 22:04 -0400, Paul Davis wrote:
> On Mon, 2007-04-23 at 16:55 -0400, Behdad Esfahbod wrote:
> 
> > I don't agree.  First, do we even envision a new platform added in the
> > following two years?  If not, this discussion is irrelevant.  And adding
> > a new platform is dead easy now: you just look at the other ones, and
> > copy and adapt one of them.  Of the four we have now, three look VERY
> > similar.  The only exception is pthread because it doesn't need static
> > initialization.
> > 
> > In fact it became so easy that I went on and implemented BeOS (a
> > platform I've never seen).  It was six lines only:
> > 
> >   typedef BLocker* cairo_mutex_t;
> > 
> > # define CAIRO_MUTEX_LOCK(name) (name)->Lock()
> > # define CAIRO_MUTEX_UNLOCK(name) (name)->Unlock()
> > # define CAIRO_MUTEX_INIT(mutex) (*(mutex)) = new BLocker()
> > # define CAIRO_MUTEX_FINI(mutex) delete (*(mutex))
> > # define CAIRO_MUTEX_NIL_INITIALIZER NULL
> 
> congratulations, you are well on your way towards virtualizing the
> already virtual. what is the justification for cairo-specific thread
> code? why are you not just using an existing cross platform library,
> even if that means ripping out its thread support? pthreads is already
> virtualized, and then glib sits on top of that, and wine has its own
> virtual handlers for things that might be pthreads and might not be.
> P.1003 *is* a standard folks. Yes, MS don't provide a version, but is
> this the sole justification for reimplementing (badly, or at least,
> superficially) was has already been done?

Be assured that we don't love this work.  In fact the commits I had to
make to cairo last week became so frustrating that I blogged about it:

  http://mces.blogspot.com/2007/04/cost-of-code-refactoring.html


It's just by demand.  And while I personally don't care about any
non-Linux system, I don't think as a maintainer, it would be very
responsible of me to say "I don't care about your platform" when someone
submits a patch.  I'm sure many maintainers of many Free Software
projects feel the same.

Using glib on the other is a completely different issue.  One that it's
too late to discuss anyway.

-- 
behdad
http://behdad.org/

"Those who would give up Essential Liberty to purchase a little
 Temporary Safety, deserve neither Liberty nor Safety."
        -- Benjamin Franklin, 1759