[PATCH v2 08/13] libmultipath: factor out code to check if a device is a parition

[Benjamin Marzinski]

Move the code to check if a device is a valid parition of a multipath
device out into it's own function. A future patch will make this code
more complicated. No functional changes.

Signed-off-by: Benjamin Marzinski <bmarz...@redhat.com>
---
 libmultipath/devmapper.c | 57 ++++++++++++++++++++--------------------
 1 file changed, 29 insertions(+), 28 deletions(-)

diff --git a/libmultipath/devmapper.c b/libmultipath/devmapper.c
index b0bd0d4f..0df9ee40 100644
--- a/libmultipath/devmapper.c
+++ b/libmultipath/devmapper.c
@@ -1318,17 +1318,43 @@ char *dm_mapname(int major, int minor)
        return strdup(name);
 }
 
+static bool
+is_valid_partmap(const char *name, const char *map_dev_t,
+                const char *map_uuid) {
+       int r;
+       char __attribute__((cleanup(cleanup_charp))) *params = NULL;
+       char *p;
+       char part_uuid[DM_UUID_LEN];
+
+       r = libmp_mapinfo(DM_MAP_BY_NAME | MAPINFO_PART_ONLY | 
MAPINFO_CHECK_UUID,
+                         (mapid_t) { .str = name },
+                         (mapinfo_t) { .uuid = part_uuid, .target = &params});
+
+       /* There must be a single linear target */
+       if (r != DMP_OK)
+               return false;
+
+       /*
+        * and the uuid of the target must be a partition of the uuid of the
+        * multipath device
+        */
+       if (!is_mpath_part_uuid(part_uuid, map_uuid))
+               return false;
+
+       /* and the table must map over the multipath map */
+       return ((p = strstr(params, map_dev_t)) &&
+               !isdigit(*(p + strlen(map_dev_t))));
+}
+
 static int
 do_foreach_partmaps (const char *mapname,
                     int (*partmap_func)(const char *, void *),
                     void *data)
 {
        struct dm_task __attribute__((cleanup(cleanup_dm_task))) *dmt = NULL;
-       char __attribute__((cleanup(cleanup_charp))) *params = NULL;
        struct dm_names *names;
        unsigned next = 0;
        char dev_t[BLK_DEV_SIZE];
-       char *p;
        char map_uuid[DM_UUID_LEN];
        struct dm_info info;
 
@@ -1354,35 +1380,10 @@ do_foreach_partmaps (const char *mapname,
                return 0;
 
        do {
-               char part_uuid[DM_UUID_LEN];
-
-               if (
-                   /*
-                    * if there is only a single "linear" target
-                    */
-                   libmp_mapinfo(DM_MAP_BY_NAME | MAPINFO_PART_ONLY | 
MAPINFO_CHECK_UUID,
-                                 (mapid_t) { .str = names->name },
-                                 (mapinfo_t) {
-                                         .uuid = part_uuid,
-                                         .target = &params,
-                                 }) == DMP_OK &&
-                   /*
-                    * and the uuid of the target is a partition of the
-                    * uuid of the multipath device
-                    */
-                   is_mpath_part_uuid(part_uuid, map_uuid) &&
-
-                   /*
-                    * and the table maps over the multipath map
-                    */
-                   (p = strstr(params, dev_t)) &&
-                   !isdigit(*(p + strlen(dev_t))) &&
-
+               if (is_valid_partmap(names->name, dev_t, map_uuid) &&
                    (partmap_func(names->name, data) != 0))
                        return 1;
 
-               free(params);
-               params = NULL;
                next = names->next;
                names = (void*) names + next;
        } while (next);
-- 
2.46.2