s3:idmap:autorid: simplify the id->sid calculation

To make it more intutive.

rid = reduced_rid + domain_range_index * range_size

where

reduced_rid = (id - id_low) % range_size

Signed-off-by: Michael Adam <obnox@samba.org>
Reviewed-by: Christian Ambach <ambi@samba.org>

diff --git a/source3/winbindd/idmap_autorid.c b/source3/winbindd/idmap_autorid.c
index 32d5860ae61fa4e724922fb476bd04544f3a60bf..5ed0255bd0e45c8a19088adef0f1e406b6ef5f6b 100644 (file)
--- a/source3/winbindd/idmap_autorid.c
+++ b/source3/winbindd/idmap_autorid.c
@@ -260,8 +260,11 @@ static NTSTATUS idmap_autorid_id_to_sid(struct autorid_global_config *cfg,
                                        struct idmap_domain *dom,
                                        struct id_map *map)
 {
-       uint32_t range;
+       uint32_t range_number;
        uint32_t domain_range_index = 0;
+       uint32_t normalized_id;
+       uint32_t reduced_rid;
+       uint32_t rid;
        TDB_DATA data = tdb_null;
        char *keystr;
        struct dom_sid domsid;
@@ -285,9 +288,11 @@ static NTSTATUS idmap_autorid_id_to_sid(struct autorid_global_config *cfg,
        }
 
        /* determine the range of this uid */
-       range = ((map->xid.id - cfg->minvalue) / cfg->rangesize);
 
-       keystr = talloc_asprintf(talloc_tos(), "%u", range);
+       normalized_id = map->xid.id - cfg->minvalue;
+       range_number = normalized_id / cfg->rangesize;
+
+       keystr = talloc_asprintf(talloc_tos(), "%u", range_number);
        if (!keystr) {
                return NT_STATUS_NO_MEMORY;
        }
@@ -298,7 +303,7 @@ static NTSTATUS idmap_autorid_id_to_sid(struct autorid_global_config *cfg,
        if (!NT_STATUS_IS_OK(status)) {
                DEBUG(4, ("id %d belongs to range %d which does not have "
                          "domain mapping, ignoring mapping request\n",
-                         map->xid.id, range));
+                         map->xid.id, range_number));
                TALLOC_FREE(data.dptr);
                map->status = ID_UNKNOWN;
                return NT_STATUS_OK;
@@ -331,9 +336,10 @@ static NTSTATUS idmap_autorid_id_to_sid(struct autorid_global_config *cfg,
                        return NT_STATUS_OK;
                }
 
-       sid_compose(map->sid, &domsid,
-                   (map->xid.id - cfg->minvalue -
-                    range * cfg->rangesize + (cfg->rangesize * domain_range_index)));
+       reduced_rid = normalized_id % cfg->rangesize;
+       rid = reduced_rid + domain_range_index * cfg->rangesize;
+
+       sid_compose(map->sid, &domsid, rid);
 
        /* We **really** should have some way of validating
           the SID exists and is the correct type here.  But