[Reviving a more than 1-year old thread. I randomly noticed this (refer
below) while browsing through AF_VSOCK changes in my 'qemu-devel'
maildir.]
On Tue, Oct 18, 2016 at 11:21:23AM +0100, Stefan Hajnoczi wrote:
> On Mon, Oct 17, 2016 at 09:25:46AM -0500, Eric Blake wrote:
> > On 10/16/2016 08:35 AM, Stefan Hajnoczi wrote:
> >
> > >>> +
> > >>> + if (sscanf(str, "%32[^:]:%32[^,]%n", cid, port, &n) != 2) {
> > >>
> > >> This says stop at the first comma after the colon...
> > >>
> > >>> + error_setg(errp, "error parsing address '%s'", str);
> > >>> + return NULL;
> > >>> + }
> > >>> + if (str[n] != '\0') {
> > >>> + error_setg(errp, "trailing characters in address '%s'", str);
> > >>
> > >> ...but this rejects a trailing comma. Is a trailing comma possible base
> > >> on how QemuOpts work? If so, do you need to handle it here?
> > >
> > > Actually I just wanted to grab characters up until the end of string.
> > > It wasn't clear from the sscanf(3) man page what the best way to do that
> > > was, so I kept the comma which is also used in tcp addresses (because
> > > they support additional comma-separated options).
> >
> > %32s instead of %32[^,] should grab up to all 32 remaining characters in
> > the string; your %n trick then ensures there is no garbage. I guess
> > it's still a question of whether we want to always treat a comma as
> > trailing garbage.
>
> No comma options are currently accepted. Treating comma as garbage
> seems okay.
>
> Mike: Please change %32[^,] to %32s when merging. Thanks!
The above change didn't take place while merging at that time as part of
v2.7.0-1720-g6a02c80.
I still see %32[^,] in all the sscanf(3) calls in
util/util/qemu-sockets.c
Is it still important to change?
--
/kashyap
