From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46976) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dxyYn-00013D-Pg for qemu-devel@nongnu.org; Fri, 29 Sep 2017 12:54:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dxyYn-00033V-2B for qemu-devel@nongnu.org; Fri, 29 Sep 2017 12:54:45 -0400 From: Max Reitz Date: Fri, 29 Sep 2017 18:53:30 +0200 Message-Id: <20170929165347.29658-9-mreitz@redhat.com> In-Reply-To: <20170929165347.29658-1-mreitz@redhat.com> References: <20170929165347.29658-1-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH v6 08/25] block: Add bdrv_make_absolute_filename() 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 List-ID: 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 --- block.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/block.c b/block.c index 488abfbfc4..2da242c1e9 100644 --- a/block.c +++ b/block.c @@ -308,13 +308,24 @@ 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