Re: [PATCH] Add compat/vsnprintf.c for systems that returns -1 on maxsize reached

[Wayne Davison <wayne@opencoder.net>]

On Wed, Mar 05, 2008 at 04:00:06PM +0100, Michal Rokos wrote:
> +		[[char buf[1];
> +		  if (test_vsnprintf(buf, 1, "%s", "12345") != 5) return 1;
> +		  if (snprintf(buf, 1, "%s", "12345") != 5) return 1]])],

I'd suggest using a longer buf, requesting a longer length (e.g. 3
instead of 1), and then making sure that the resulting buf is right
(e.g. "12" instead of "123").

		[[char buf[6];
		  if (test_vsnprintf(buf, 3, "%s", "12345") != 5
		   || strcmp(buf, "12") != 0) return 1;
		  if (snprintf(buf, 3, "%s", "12345") != 5
		   || strcmp(buf, "12") != 0) return 1]])],

Then, set a define that snprintf is bogus and use a version of
snprintf() based on this instead:

http://rsync.samba.org/ftp/unpacked/rsync/lib/snprintf.c

That defines rsync_snprintf() and rsync_vsnprintf() functions (which
could be renamed for git).  Then, in a global .h file, add something
like this:

#if !defined HAVE_VSNPRINTF || !defined HAVE_C99_VSNPRINTF
#define vsnprintf rsync_vsnprintf
int vsnprintf(char *str, size_t count, const char *fmt, va_list args);
#endif

#if !defined HAVE_SNPRINTF || !defined HAVE_C99_VSNPRINTF
#define snprintf rsync_snprintf
int snprintf(char *str, size_t count, const char *fmt,...);
#endif

Just be sure to put those that after the various system includes so that
they are not adversely affected.

..wayne..