From f70edf99483e7ee5f89d69fd0c51d04a35f03932 Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Fri, 25 Apr 2014 16:50:34 +0200 Subject: blockdev: Clean up fragile use of error_is_set() Using error_is_set(ERRP) to find out whether a function failed is either wrong, fragile, or unnecessarily opaque. It's wrong when ERRP may be null, because errors go undetected when it is. It's fragile when proving ERRP non-null involves a non-local argument. Else, it's unnecessarily opaque (see commit 84d18f0). The error_is_set(errp) in internal_snapshot_prepare() is merely fragile, because the caller never passes a null errp argument. Make the code more robust and more obviously correct: receive the error in a local variable, then propagate it through the parameter. Signed-off-by: Markus Armbruster Reviewed-by: Kevin Wolf Signed-off-by: Stefan Hajnoczi --- blockdev.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'blockdev.c') diff --git a/blockdev.c b/blockdev.c index 09826f10cf..952eb60e3d 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1115,6 +1115,7 @@ typedef struct InternalSnapshotState { static void internal_snapshot_prepare(BlkTransactionState *common, Error **errp) { + Error *local_err = NULL; const char *device; const char *name; BlockDriverState *bs; @@ -1163,8 +1164,10 @@ static void internal_snapshot_prepare(BlkTransactionState *common, } /* check whether a snapshot with name exist */ - ret = bdrv_snapshot_find_by_id_and_name(bs, NULL, name, &old_sn, errp); - if (error_is_set(errp)) { + ret = bdrv_snapshot_find_by_id_and_name(bs, NULL, name, &old_sn, + &local_err); + if (local_err) { + error_propagate(errp, local_err); return; } else if (ret) { error_setg(errp, -- cgit v1.2.3