From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42752) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fnsbB-0002Sy-OS for qemu-devel@nongnu.org; Thu, 09 Aug 2018 17:36:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fnsbA-00082P-SA for qemu-devel@nongnu.org; Thu, 09 Aug 2018 17:36:01 -0400 From: Max Reitz Date: Thu, 9 Aug 2018 23:35:09 +0200 Message-Id: <20180809213528.14738-13-mreitz@redhat.com> In-Reply-To: <20180809213528.14738-1-mreitz@redhat.com> References: <20180809213528.14738-1-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH for-3.1 v10 12/31] 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 , Eric Blake , Alberto Garcia 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 | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) diff --git a/block.c b/block.c index 369c8fa027..6606eeb7f4 100644 --- a/block.c +++ b/block.c @@ -319,16 +319,29 @@ 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; + char *bs_filename; - bdrv_refresh_filename(bs); + bdrv_refresh_filename(relative_to); + + bs_filename = relative_to->exact_filename[0] + ? relative_to->exact_filename + : relative_to->filename; - backed = bs->exact_filename[0] ? bs->exact_filename : bs->filename; - return bdrv_get_full_backing_filename_from_filename(backed, - bs->backing_file, - errp); + return bdrv_get_full_backing_filename_from_filename(bs_filename, + filename ?: "", 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) -- 2.17.1