diff options
Diffstat (limited to 'src/backend/utils/cache/relmapper.c')
| -rw-r--r-- | src/backend/utils/cache/relmapper.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/src/backend/utils/cache/relmapper.c b/src/backend/utils/cache/relmapper.c index 2c7d9f3287b..18f0342a7de 100644 --- a/src/backend/utils/cache/relmapper.c +++ b/src/backend/utils/cache/relmapper.c @@ -181,6 +181,59 @@ RelationMapOidToFilenode(Oid relationId, bool shared) } /* + * RelationMapFilenodeToOid + * + * Do the reverse of the normal direction of mapping done in + * RelationMapOidToFilenode. + * + * This is not supposed to be used during normal running but rather for + * information purposes when looking at the filesystem or xlog. + * + * Returns InvalidOid if the OID is not known; this can easily happen if the + * relfilenode doesn't pertain to a mapped relation. + */ +Oid +RelationMapFilenodeToOid(Oid filenode, bool shared) +{ + const RelMapFile *map; + int32 i; + + /* If there are active updates, believe those over the main maps */ + if (shared) + { + map = &active_shared_updates; + for (i = 0; i < map->num_mappings; i++) + { + if (filenode == map->mappings[i].mapfilenode) + return map->mappings[i].mapoid; + } + map = &shared_map; + for (i = 0; i < map->num_mappings; i++) + { + if (filenode == map->mappings[i].mapfilenode) + return map->mappings[i].mapoid; + } + } + else + { + map = &active_local_updates; + for (i = 0; i < map->num_mappings; i++) + { + if (filenode == map->mappings[i].mapfilenode) + return map->mappings[i].mapoid; + } + map = &local_map; + for (i = 0; i < map->num_mappings; i++) + { + if (filenode == map->mappings[i].mapfilenode) + return map->mappings[i].mapoid; + } + } + + return InvalidOid; +} + +/* * RelationMapUpdateMap * * Install a new relfilenode mapping for the specified relation. |