Johan Rydberg <[EMAIL PROTECTED]> writes: > This code can be shorter; you only have to compare the lengths. If > they match, you can do a memcmp on the whole device path.
It could look something like this;
/* Returns zero if device path SUBPATH is a subpath of device path
PATH. */
static int
compare_subpath (const grub_efi_device_path_t *subpath,
const grub_efi_device_path_t *path)
{
if (! subpath || ! path)
return 1;
while (1)
{
int len, ret;
if (GRUB_EFI_END_ENTIRE_DEVICE_PATH (subpath))
return 0;
else if (GRUB_EFI_END_ENTIRE_DEVICE_PATH (path))
return 1;
if (GRUB_EFI_DEVICE_PATH_LENGTH (subpath)
!= GRUB_EFI_DEVICE_PATH_LENGTH (path))
return ((int) GRUB_EFI_DEVICE_PATH_LENGTH (subpath)
- (int) GRUB_EFI_DEVICE_PATH_LENGTH (path));
len = GRUB_EFI_DEVICE_PATH_LENGTH (path);
ret = grub_memcmp (subpath, path, len);
if (ret)
return ret;
path = (grub_efi_device_path_t *) ((char *) path + len);
subpath = (grub_efi_device_path_t *) ((char *) subpath + len);
}
}
I guess that should work at least, it is not tested.
In gnufi I have a device_path_iterate function that could be used for
these kind of things. Maybe we should bring it in to GRUB2.
/* Iterate nodes of the device path. *PATHP should be set to point to
the path that is to be iterated. NULL will be returned when the
end of the path has been reached. */
efi_device_path_t *
efi_device_path_iterate (efi_device_path_t **pathp)
{
efi_device_path_t *p = *pathp;
if (EFI_END_ENTIRE_DEVICE_PATH (p))
return NULL;
else
{
efi_uint_t len = EFI_DEVICE_PATH_LENGTH (p);
*pathp = (efi_device_path_t *) (((char *) p) + len);
return p;
}
}
~j
pgpfuh7RNvMft.pgp
Description: PGP signature
_______________________________________________ Grub-devel mailing list Grub-devel@gnu.org http://lists.gnu.org/mailman/listinfo/grub-devel
