Re: [PATCH 22/40] Windows: Implement asynchronous functions as threads.

From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Feb 29, 2008, 01:17 UTC
Message-ID: <alpine.LSU.1.00.0802290112340.22527@racer.site>
In-Reply-To: <200802282201.06802.johannes.sixt@telecom.at>

Hi,

On Thu, 28 Feb 2008, Johannes Sixt wrote:

Show 22 quoted lines

> On Thursday 28 February 2008 16:28, Johannes Schindelin wrote:
>
> > On Wed, 27 Feb 2008, Johannes Sixt wrote:
> > > In upload-pack we must explicitly close the output channel of 
> > > rev-list. (On Unix, the channel is closed automatically because 
> > > process that runs rev-list terminates.)
> >
> > When I read this patch, my impression was that it litters the source 
> > code with #ifdef's.  IMO this makes the code less readable, and as a 
> > consequence easer to fsck up.
> >
> > Unfortunately, I have no idea how to help that, other than 
> > implementing compat/thread.[ch], abstracting the thread functions, and 
> > introducing a NO_FORK Makefile variable and preprocessor constant.
> >
> > Hmpf.
> 
> The number of #ifdef/#endif is already at a minimum unless you are 
> willing to have entire functions in separate #ifdef/#else/#endif 
> branches. Whether to have compat/thread.[ch] or not is just a question 
> of whether you want to have asynchronous functions in threads also on 
> Unix or not.

Well, my idea was that Git's code looks as good as it does now not only because the functions are well written, but because the conditionally-compiled code is not classified by _platform_ but by _reason_.

For example, we do not write that on FreeBSD, we do this and that, but we define for FreeBSD that there is no strlcpy(), and if NO_STRLCPY is defined, we implement it.

Likewise, I would prefer to have it in the code here _not_ that we do this and that on MinGW32, but that in the absence of a usable fork(), we require certain functions (declared in compat/thread.h, for example), and use them.

But I know this is a lot of work, so I hoped for a better solution, that still excites my "elegance neuron".

Ciao, Dscho