On Fri, Aug 10, 2012 at 01:54:26PM +1000, Peter A. G. Crosthwaite wrote: > The sizep arg is populated with the size of the loaded device tree. Since this > is one of those informational "please populate" type arguments it should be > optional. Guarded writes to *sizep against NULL accordingly. > > Signed-off-by: Peter A. G. Crosthwaite <peter.crosthwa...@petalogix.com> > Acked-by: Alexander Graf <ag...@suse.de> > --- > device_tree.c | 8 ++++++-- > 1 files changed, 6 insertions(+), 2 deletions(-) > > diff --git a/device_tree.c b/device_tree.c > index d7a9b6b..641a48a 100644 > --- a/device_tree.c > +++ b/device_tree.c > @@ -71,7 +71,9 @@ void *load_device_tree(const char *filename_path, int > *sizep) > int ret; > void *fdt = NULL; > > - *sizep = 0; > + if (sizep) { > + *sizep = 0; > + } > dt_size = get_image_size(filename_path); > if (dt_size < 0) { > printf("Unable to get size of device tree file '%s'\n", > @@ -104,7 +106,9 @@ void *load_device_tree(const char *filename_path, int > *sizep) > filename_path); > goto fail; > } > - *sizep = dt_size; > + if (sizep) { > + *sizep = dt_size; > + }
What can the caller do with this void* buffer without knowing its size? They cannot hand the buffer to the guest unless they duplicate the get_image_size() call, which is pointless, or we're assuming a fixed size, which is unsafe. I'm asking what the legitimate use case for sizep == NULL is? Stefan