Re: [Qemu-devel] [PATCH v2 09/20] cow: correctly propagate errors

[Kevin Wolf <kwolf@redhat.com>]

Am 11.02.2014 um 18:03 hat Paolo Bonzini geschrieben:
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  block/cow.c | 12 +++---------
>  1 file changed, 3 insertions(+), 9 deletions(-)
> 
> diff --git a/block/cow.c b/block/cow.c
> index 7fc0b12..43a2150 100644
> --- a/block/cow.c
> +++ b/block/cow.c
> @@ -82,7 +82,7 @@ static int cow_open(BlockDriverState *bs, QDict *options, int flags,
>          char version[64];
>          snprintf(version, sizeof(version),
>                 "COW version %d", cow_header.version);
> -        qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
> +        error_set(errp, QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
>              bs->device_name, "cow", version);
>          ret = -ENOTSUP;
>          goto fail;
> @@ -330,7 +330,6 @@ static int cow_create(const char *filename, QEMUOptionParameter *options,
>      struct stat st;
>      int64_t image_sectors = 0;
>      const char *image_filename = NULL;
> -    Error *local_err = NULL;
>      int ret;
>      BlockDriverState *cow_bs;
>  
> @@ -344,18 +343,13 @@ static int cow_create(const char *filename, QEMUOptionParameter *options,
>          options++;
>      }
>  
> -    ret = bdrv_create_file(filename, options, &local_err);
> +    ret = bdrv_create_file(filename, options, errp);
>      if (ret < 0) {
> -        qerror_report_err(local_err);
> -        error_free(local_err);
>          return ret;
>      }
>  
> -    ret = bdrv_file_open(&cow_bs, filename, NULL, NULL, BDRV_O_RDWR,
> -                         &local_err);
> +    ret = bdrv_file_open(&cow_bs, filename, NULL, NULL, BDRV_O_RDWR, errp);
>      if (ret < 0) {
> -        qerror_report_err(local_err);
> -        error_free(local_err);
>          return ret;
>      }

This is technically correct, but I think general policy is that using
the local_err pattern is preferred anyway.

Kevin