From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45577) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cTEDd-0000l7-NR for qemu-devel@nongnu.org; Mon, 16 Jan 2017 15:49:34 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cTEDc-0003lf-Q9 for qemu-devel@nongnu.org; Mon, 16 Jan 2017 15:49:33 -0500 From: Max Reitz Date: Mon, 16 Jan 2017 21:49:06 +0100 Message-Id: <20170116204921.31578-3-mreitz@redhat.com> In-Reply-To: <20170111181432.18868-1-mreitz@redhat.com> References: <20170111181432.18868-1-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH v4 10/25] block: Add bdrv_dirname() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, Max Reitz , Alberto Garcia , Kevin Wolf , Eric Blake This function may be implemented by block drivers to derive a directory name from a BDS. Concatenating this g_free()-able string with a relative filename must result in a valid (not necessarily existing) filename, so this is a function that should generally be not implemented by format drivers, because this is protocol-specific. If a BDS's driver does not implement this function, bdrv_dirname() will fall through to the BDS's file if it exists. If it does not, the exact_filename field will be used to generate a directory name. Signed-off-by: Max Reitz --- include/block/block.h | 1 + include/block/block_int.h | 1 + block.c | 26 ++++++++++++++++++++++++++ 3 files changed, 28 insertions(+) diff --git a/include/block/block.h b/include/block/block.h index eb41956bf1..7bcbd05338 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -439,6 +439,7 @@ char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp); char *bdrv_get_full_backing_filename_from_filename(const char *backed, const char *backing, Error **errp); +char *bdrv_dirname(BlockDriverState *bs, Error **errp); int path_has_protocol(const char *path); int path_is_absolute(const char *path); diff --git a/include/block/block_int.h b/include/block/block_int.h index c1f057ab47..fb916a7890 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -130,6 +130,7 @@ struct BlockDriver { int (*bdrv_make_empty)(BlockDriverState *bs); void (*bdrv_refresh_filename)(BlockDriverState *bs, QDict *options); + char *(*bdrv_dirname)(BlockDriverState *bs, Error **errp); /* aio */ BlockAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs, diff --git a/block.c b/block.c index 2735ec4bcc..e591e326c5 100644 --- a/block.c +++ b/block.c @@ -4083,6 +4083,32 @@ void bdrv_refresh_filename(BlockDriverState *bs) } } +char *bdrv_dirname(BlockDriverState *bs, Error **errp) +{ + BlockDriver *drv = bs->drv; + + if (!drv) { + error_setg(errp, "Node '%s' is ejected", bs->node_name); + return NULL; + } + + if (drv->bdrv_dirname) { + return drv->bdrv_dirname(bs, errp); + } + + if (bs->file) { + return bdrv_dirname(bs->file->bs, errp); + } + + if (bs->exact_filename[0] != '\0') { + return path_combine(bs->exact_filename, ""); + } + + error_setg(errp, "Cannot generate a base directory for %s nodes", + drv->format_name); + return NULL; +} + /* * Hot add/remove a BDS's child. So the user can take a child offline when * it is broken and take a new child online -- 2.11.0