[libvirt] [PATCH 3/4] conf: snapshot: Refactor virDomainSnapshotDefAssignExternalNames

[Erik Skultety]

On 11/02/16 10:20, Peter Krempa wrote:
> Get rid of one indentation level by negating condition and remove ugly
> pointer arithmetic at the cost of one extra allocation.
> ---
>  src/conf/snapshot_conf.c | 94 +++++++++++++++++++++++-------------------------
>  1 file changed, 44 insertions(+), 50 deletions(-)
> 
> diff --git a/src/conf/snapshot_conf.c b/src/conf/snapshot_conf.c
> index da6fec5..f8a1aed 100644
> --- a/src/conf/snapshot_conf.c
> +++ b/src/conf/snapshot_conf.c
> @@ -440,66 +440,60 @@ virDomainSnapshotDefParseString(const char *xmlStr,
> ...
> ... 
> -            tmp = strrchr(original, '.');
> -            if (!tmp || strchr(tmp, '/')) {
> -                if (virAsprintf(&disk->src->path, "%s.%s", original,
> -                                def->name) < 0)
> -                    goto cleanup;
> -            } else {
> -                if ((tmp - original) > INT_MAX) {
> -                    virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> -                                   _("integer overflow"));
> -                    goto cleanup;
> -                }
> -                if (virAsprintf(&disk->src->path, "%.*s.%s",
> -                                (int) (tmp - original), original,
> -                                def->name) < 0)
> -                    goto cleanup;
> -            }

This was black magic indeed.

> +        if (!(origpath = virDomainDiskGetSource(def->dom->disks[i]))) {
> +            virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
> +                           _("cannot generate external snapshot name "
> +                             "for disk '%s' without source"),
> +                           disk->name);
> +            return -1;
>          }
> -    }
> 
> -    ret = 0;
> +        if (stat(origpath, &sb) < 0 || !S_ISREG(sb.st_mode)) {
> +            virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
> +                           _("source for disk '%s' is not a regular "
> +                             "file; refusing to generate external "
> +                             "snapshot name"),
> +                           disk->name);
> +            return -1;
> +        }
> 
> - cleanup:
> -    return ret;
> +        if (VIR_STRDUP(tmppath, origpath) < 0)
> +            return -1;
> +
> +        /* drop suffix of the file name */
> +        if ((tmp = strrchr(tmppath, '.')) && !strchr(tmp, '/'))
> +            *tmp = '\0';
> +
> +        if (virAsprintf(&disk->src->path, "%s.%s", tmppath, def->name) < 0) {
> +            VIR_FREE(tmppath);
> +            return -1;
> +        }
> +
> +        VIR_FREE(tmppath);
> +    }
> +
> +    return 0;
>  }
> 

Nicely done, ACK.

Erik