Re: [PATCH v2 33/49] libmultipath: add is_mpath_uuid() helper

[Benjamin Marzinski <bmarzins@xxxxxxxxxx>]

On Fri, Jul 12, 2024 at 07:14:41PM +0200, Martin Wilck wrote:
> Export it, as it will be used by multipathd and libmpathpersist.
> 
Reviewed-by: Benjamin Marzinski <bmarzins@xxxxxxxxxx>
> Signed-off-by: Martin Wilck <mwilck@xxxxxxxx>
> ---
>  libmultipath/devmapper.c          | 13 +++++++++----
>  libmultipath/devmapper.h          |  2 ++
>  libmultipath/libmultipath.version |  1 +
>  3 files changed, 12 insertions(+), 4 deletions(-)
> 
> diff --git a/libmultipath/devmapper.c b/libmultipath/devmapper.c
> index 9483f02..6f17d32 100644
> --- a/libmultipath/devmapper.c
> +++ b/libmultipath/devmapper.c
> @@ -840,6 +840,11 @@ int dm_get_map(const char *name, unsigned long long *size, char **outparams)
>  	}
>  }
>  
> +bool is_mpath_uuid(const char uuid[DM_UUID_LEN])
> +{
> +	return !strncmp(uuid, UUID_PREFIX, UUID_PREFIX_LEN);
> +}
> +
>  /**
>   * dm_get_wwid(): return WWID for a multipath map
>   * @returns:
> @@ -857,7 +862,7 @@ int dm_get_wwid(const char *name, char *uuid, int uuid_len)
>  	if (rc != DMP_OK)
>  		return rc;
>  
> -	if (!strncmp(tmp, UUID_PREFIX, UUID_PREFIX_LEN))
> +	if (is_mpath_uuid(tmp))
>  		strlcpy(uuid, tmp + UUID_PREFIX_LEN, uuid_len);
>  	else
>  		return DMP_NO_MATCH;
> @@ -982,7 +987,7 @@ int dm_is_mpath(const char *name)
>  
>  	switch (rc) {
>  	case DMP_OK:
> -		if (!strncmp(uuid, UUID_PREFIX, UUID_PREFIX_LEN))
> +		if (is_mpath_uuid(uuid))
>  			return DM_IS_MPATH_YES;
>  		/* fallthrough */
>  	case DMP_NOT_FOUND:
> @@ -1082,7 +1087,7 @@ int _dm_flush_map (const char *mapname, int flags, int retries)
>  			  (mapinfo_t) {
>  				  .uuid = uuid,
>  				  .target = &params }) != DMP_OK
> -	    || strncmp(uuid, UUID_PREFIX, UUID_PREFIX_LEN))
> +	    || !is_mpath_uuid(uuid))
>  		return DM_FLUSH_OK; /* nothing to do */
>  
>  	/* if the device currently has no partitions, do not
> @@ -1325,7 +1330,7 @@ struct multipath *dm_get_multipath(const char *name)
>  			  }) != DMP_OK)
>  		return NULL;
>  
> -	if (strncmp(uuid, UUID_PREFIX, UUID_PREFIX_LEN))
> +	if (!is_mpath_uuid(uuid))
>  		return NULL;
>  
>  	strlcpy(mpp->wwid, uuid + UUID_PREFIX_LEN, sizeof(mpp->wwid));
> diff --git a/libmultipath/devmapper.h b/libmultipath/devmapper.h
> index 4c8f345..a10821f 100644
> --- a/libmultipath/devmapper.h
> +++ b/libmultipath/devmapper.h
> @@ -136,6 +136,8 @@ enum {
>  	DM_IS_MPATH_YES,
>  	DM_IS_MPATH_ERR,
>  };
> +
> +bool is_mpath_uuid(const char uuid[DM_UUID_LEN]);
>  int dm_is_mpath(const char *name);
>  
>  enum {
> diff --git a/libmultipath/libmultipath.version b/libmultipath/libmultipath.version
> index 7d3ff63..5b8f9e0 100644
> --- a/libmultipath/libmultipath.version
> +++ b/libmultipath/libmultipath.version
> @@ -127,6 +127,7 @@ global:
>  	init_foreign;
>  	init_prio;
>  	io_err_stat_handle_pathfail;
> +	is_mpath_uuid;
>  	is_path_valid;
>  	libmp_dm_task_create;
>  	libmp_get_version;
> -- 
> 2.45.2