Re: [PATCH 1/2] Add strbuf_initf()

From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Mar 6, 2008, 10:53 UTC
Message-ID: <alpine.LSU.1.00.0803061148180.15786@racer.site>
In-Reply-To: <20080306063331.GA7325@glandium.org>

Hi,

On Thu, 6 Mar 2008, Mike Hommey wrote:

Show 13 quoted lines

> On Thu, Mar 06, 2008 at 02:14:43AM +0100, Johannes Schindelin wrote:
> > 
> > The most common use of addf() was to init a strbuf and addf() right 
> > away. Since it is so common, it makes sense to have a function 
> > strbuf_initf() to wrap both calls into one.
> > 
> > Unfortunately, C (and cpp) has no way to make this easy without code 
> > duplication, as we need to va_init() in strbuf_addf() possibly a few 
> > times.  So the code for addf() is copied.  Fortunately, the code is 
> > pretty short, so not too much had to be copied as-is.
> 
> The problem with code duplication is not about code size, but more about 
> not forgetting to fix bugs in all incarnations of the duplicated code.

Yes, I know.

> Is it so ugly to use a macro ?

AFAIR it is unportable to have a macro

#define strbuf_initf(buf, fmt, ...) \
	(strbuf_init(buf, strlen(fmt) + 64), strbuf_addf(buf, fmt, args);)

(GNU cpp groks it, but what about the others?)

Or you mean the whole body of the implementation of strbuf_addf()? Now, _that_ would be ugly.

Ciao, Dscho