From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35110) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eGsPC-0008GE-1H for qemu-devel@nongnu.org; Mon, 20 Nov 2017 15:10:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eGsPB-00073L-97 for qemu-devel@nongnu.org; Mon, 20 Nov 2017 15:10:58 -0500 From: Max Reitz Date: Mon, 20 Nov 2017 21:09:48 +0100 Message-Id: <20171120201004.14999-10-mreitz@redhat.com> In-Reply-To: <20171120201004.14999-1-mreitz@redhat.com> References: <20171120201004.14999-1-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH v7 for-2.12 09/25] block: Add bdrv_make_absolute_filename() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, Max Reitz , Kevin Wolf , Alberto Garcia , Eric Blake , John Snow This is a general function for making a filename that is relative to a certain BDS absolute. It calls bdrv_get_full_backing_filename_from_filename() for now, but that will be changed in a follow-up patch. Signed-off-by: Max Reitz Reviewed-by: Alberto Garcia --- block.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/block.c b/block.c index 804adceafa..a11cebf0cb 100644 --- a/block.c +++ b/block.c @@ -313,13 +313,24 @@ char *bdrv_get_full_backing_filename_from_filename(const char *backed, } } -char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp) +/* If @filename is empty or NULL, this function returns NULL without + * setting @errp. In all other cases, NULL will only be returned with + * @errp set. + */ +static char *bdrv_make_absolute_filename(BlockDriverState *relative_to, + const char *filename, Error **errp) { - char *backed = bs->exact_filename[0] ? bs->exact_filename : bs->filename; + char *bs_filename = relative_to->exact_filename[0] + ? relative_to->exact_filename + : relative_to->filename; + + return bdrv_get_full_backing_filename_from_filename(bs_filename, + filename ?: "", errp); +} - return bdrv_get_full_backing_filename_from_filename(backed, - bs->backing_file, - errp); +char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp) +{ + return bdrv_make_absolute_filename(bs, bs->backing_file, errp); } void bdrv_register(BlockDriver *bdrv) -- 2.13.6