Wireshark · Ethereal-dev: Re: [Ethereal-dev] Replace snprintf etc with GLib equivalents

[Guy Harris <gharris@xxxxxxxxx>]

On Sat, May 01, 2004 at 11:29:49PM +0200, Olivier Biot wrote:
> As we're using GLib, does anyone object if I get rid of snprintf in
> the code?

Note the comment

	Note: In versions of GLib prior to 1.2.3, this function may
	return -1 if the output was truncated, and the truncated string
	may not be NULL-terminated.

in the "g_snprintf()" and "g_vsnprintf()" documentation.

It looks as if 1.2.10 (and presumably 1.2.3 and intermediate releases)
fixes that by checking whether the underlying "snprintf()" or
"vsnprintf()" routine returns a negative value and, if so,
null-terminates the string and returns the string length.  That seems to
imply that the behavioral difference between pre-1.2.3 and 1.2.3
reflects differences between "snprintf()" implementations, in which case
we might already cope with that problem.

Note also that, for systems lacking "snprintf()", it uses the
"g_strdup_vprintf()" routine, so that's perhaps a little less efficient
than the replacement "snprintf()" - but I'm not sure what platforms lack
it, other than Digital UNIX, so maybe that's not an issue.

I also don't know whether we anywhere assume that the return value of
"snprintf()" is the number of characters the string *would* have taken
if it *hadn't* overflowed the buffer - probably not, given that we can't
even assume that it returns anything other than -1 if we overflow the
buffer.