On Fri, 2011-05-06 at 13:50 +0100, George Dunlap wrote:
> Unfortunately not.
>
> Looks like we could either make libxl__domain_bios() a #define (not
> tested), or make the argument "%s" (which seems to work, patch
> attached).
>
> Adding a format string of just a string seems kind of dumb, but I
> don't think this is a really hot path...
It's actually sensible to use "%s" when the string might be untrusted
but in this case it's really just a string literal, I guess the
laundering through a function is enough to hide that from gcc. Using %s
is the best fix, I think.
Ian.
>
> -George
>
>
> On Fri, May 6, 2011 at 1:33 PM, Ian Campbell <Ian.Campbell@xxxxxxxxxxxxx>
> wrote:
> > On Fri, 2011-05-06 at 12:14 +0100, George Dunlap wrote:
> >
> >> The line in question is:
> >> libxl__xs_write(gc, XBT_NULL, libxl__sprintf(gc, "%s/bios", path),
> >> libxl__domain_bios(gc, info));
> >>
> >> Looks like libxl__xs_write() is expecting the 4th argument to be a
> >> format string...?
> >
> > Yes, and hence it needs to be a const char * not a char *, so we should
> > change both libxl__domain_bios and libxl__xs_write I think.
> >
> > Does this help? It works for me, but my compiler doesn't appear to
> > complain in this way...
> >
> > Ian.
> >
> > 8<-------------------------------------------
> >
> > # HG changeset patch
> > # User Ian Campbell <ian.campbell@xxxxxxxxxx>
> > # Date 1304685175 -3600
> > # Node ID 4e5487962178e7affd7d7d0341a90dde8c60915e
> > # Parent faca1c90188e536eb0f02992c766d06759be376f
> > libxl: libxl__xs_write format string should be const.
> >
> > George Dunlap reports that gcc 4.4.3 complains:
> > libxl_dm.c: In function libxl__create_device_mode:
> > libxl_dm.c:776: error: format not a string literal and no format
> > arguments
> > And indeed the format argument here is a char * from libxl__domain_bios().
> >
> > Make the argument to libxl__xs_write a const char * and change
> > libxl__domain_bios to return a const char too.
> >
> > Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
> >
> > diff -r faca1c90188e -r 4e5487962178 tools/libxl/libxl_dm.c
> > --- a/tools/libxl/libxl_dm.c Fri May 06 13:14:24 2011 +0100
> > +++ b/tools/libxl/libxl_dm.c Fri May 06 13:32:55 2011 +0100
> > @@ -68,12 +68,12 @@ const char *libxl__domain_device_model(l
> > return dm;
> > }
> >
> > -static char *libxl__domain_bios(libxl__gc *gc,
> > +static const char *libxl__domain_bios(libxl__gc *gc,
> > libxl_device_model_info *info)
> > {
> > switch (info->device_model_version) {
> > - case 1: return libxl__strdup(gc, "rombios");
> > - case 2: return libxl__strdup(gc, "seabios");
> > + case 1: return "rombios";
> > + case 2: return "seabios";
> > default:return NULL;
> > }
> > }
> > diff -r faca1c90188e -r 4e5487962178 tools/libxl/libxl_internal.h
> > --- a/tools/libxl/libxl_internal.h Fri May 06 13:14:24 2011 +0100
> > +++ b/tools/libxl/libxl_internal.h Fri May 06 13:32:55 2011 +0100
> > @@ -153,7 +153,7 @@ _hidden char **libxl__xs_kvs_of_flexarra
> > _hidden int libxl__xs_writev(libxl__gc *gc, xs_transaction_t t,
> > char *dir, char **kvs);
> > _hidden int libxl__xs_write(libxl__gc *gc, xs_transaction_t t,
> > - char *path, char *fmt, ...) PRINTF_ATTRIBUTE(4, 5);
> > + char *path, const char *fmt, ...) PRINTF_ATTRIBUTE(4,
> > 5);
> > /* Each fn returns 0 on success.
> > * On error: returns -1, sets errno (no logging) */
> >
> > diff -r faca1c90188e -r 4e5487962178 tools/libxl/libxl_xshelp.c
> > --- a/tools/libxl/libxl_xshelp.c Fri May 06 13:14:24 2011 +0100
> > +++ b/tools/libxl/libxl_xshelp.c Fri May 06 13:32:55 2011 +0100
> > @@ -69,7 +69,7 @@ int libxl__xs_writev(libxl__gc *gc, xs_t
> > }
> >
> > int libxl__xs_write(libxl__gc *gc, xs_transaction_t t,
> > - char *path, char *fmt, ...)
> > + char *path, const char *fmt, ...)
> > {
> > libxl_ctx *ctx = libxl__gc_owner(gc);
> > char *s;
> >
> >
> >
> > _______________________________________________
> > Xen-devel mailing list
> > Xen-devel@xxxxxxxxxxxxxxxxxxx
> > http://lists.xensource.com/xen-devel
> >
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
Home