On Mar 9, 2008, at 5:38 PM, Wayne Davison wrote:

> On Sun, Mar 09, 2008 at 10:51:42AM -0400, Jeff Johnson wrote:
>> Meanwhile, below is a rewrite of POPT_fprintf, essentially identical
>> to the "man vsnprintf" example. See what you think ...
>
> Looks good.  I did some tweaking based on this code.  The attached  
> patch
> changes what you checked-in to CVS.  See if you agree with these  
> points:
>
> 1. If the system has vasprintf(), just use that (avoiding issues 2  
> & 3).
>

Agreed.

> 2. Always allocate one more byte than we need, just in case the  
> system's
>    vsprintf() has an off-by-one bug with the limit.
>

That's kinda nutty (but hurts nothing). I'd rather fix a known problem
rather than trying to anticipate all possibilities ...

> 3. Moved the va_start() and va_end() calls back in the loop because I
>    believe that the systems that needed a va_copy() in the old code
>    won't like the reuse of "ap" without it.
>

... afaik 3) is  <varargs.h> vs <stdarg.h> implementation dependent
confusion with va_start() and va_end(). But hurts nothing at all ...

> Bonus question:  I didn't think older systems supported the idiom of
> realloc(NULL, len) doing a malloc().  I didn't check to see if that
> idiom is already used elsewhere in the popt code, though, so I just
> left that alone.
>

... and my ultimate answer is:

      Deranged and ancient uglix-like systems, with busted vsnpprintf  
and other damage,
      can certainly live with gud old fprintf(3) as popt _USED_ to do  
without all this dain bread
      conversion from UTF-* to the native locale using iconv &  
vsnprintf & nl_langinfo & wide characters &
      malloc'ing fprintf's & ....

None of this modern crapola existed on systems that had busted  
v*printf() implementations, almost
all the problems disappear with
     #define POPT_fprintf	fprintf
(and some tweaks to test whether POPT_fprintf is defined). KISS is  
always better ...

> I tested both sides of the HAVE_VASPRINTF code and this seems good to
> me.
>

Off to tweak in vasprintf(3) ... I am happy to see sprintf start to  
vanish ...

73 de Jeff