diff options
Diffstat (limited to 'src/backend')
| -rw-r--r-- | src/backend/catalog/namespace.c | 93 |
1 files changed, 91 insertions, 2 deletions
diff --git a/src/backend/catalog/namespace.c b/src/backend/catalog/namespace.c index e7fd1c1e5c0..fa0d20af307 100644 --- a/src/backend/catalog/namespace.c +++ b/src/backend/catalog/namespace.c @@ -13,7 +13,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/catalog/namespace.c,v 1.41 2002/12/04 05:18:31 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/catalog/namespace.c,v 1.42 2002/12/12 21:02:19 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -143,7 +143,7 @@ Datum pg_type_is_visible(PG_FUNCTION_ARGS); Datum pg_function_is_visible(PG_FUNCTION_ARGS); Datum pg_operator_is_visible(PG_FUNCTION_ARGS); Datum pg_opclass_is_visible(PG_FUNCTION_ARGS); - +Datum pg_conversion_is_visible(PG_FUNCTION_ARGS); /* * RangeVarGetRelid @@ -1036,6 +1036,87 @@ OpclassIsVisible(Oid opcid) } /* + * ConversionGetConid + * Try to resolve an unqualified conversion name. + * Returns OID if conversion found in search path, else InvalidOid. + * + * This is essentially the same as RelnameGetRelid. + */ +Oid +ConversionGetConid(const char *conname) +{ + Oid conid; + List *lptr; + + recomputeNamespacePath(); + + foreach(lptr, namespaceSearchPath) + { + Oid namespaceId = (Oid) lfirsti(lptr); + + conid = GetSysCacheOid(CONNAMENSP, + PointerGetDatum(conname), + ObjectIdGetDatum(namespaceId), + 0, 0); + if (OidIsValid(conid)) + return conid; + } + + /* Not found in path */ + return InvalidOid; +} + +/* + * ConversionIsVisible + * Determine whether a conversion (identified by OID) is visible in the + * current search path. Visible means "would be found by searching + * for the unqualified conversion name". + */ +bool +ConversionIsVisible(Oid conid) +{ + HeapTuple contup; + Form_pg_conversion conform; + Oid connamespace; + bool visible; + + contup = SearchSysCache(CONOID, + ObjectIdGetDatum(conid), + 0, 0, 0); + if (!HeapTupleIsValid(contup)) + elog(ERROR, "Cache lookup failed for converions %u", conid); + conform = (Form_pg_conversion) GETSTRUCT(contup); + + recomputeNamespacePath(); + + /* + * Quick check: if it ain't in the path at all, it ain't visible. + * Items in the system namespace are surely in the path and so we + * needn't even do intMember() for them. + */ + connamespace = conform->connamespace; + if (connamespace != PG_CATALOG_NAMESPACE && + !intMember(connamespace, namespaceSearchPath)) + visible = false; + else + { + /* + * If it is in the path, it might still not be visible; it could + * be hidden by another conversion of the same name earlier in the + * path. So we must do a slow check to see if this conversion would + * be found by ConvnameGetConid. + */ + char *conname = NameStr(conform->conname); + + visible = (ConversionGetConid(conname) == conid); + } + + ReleaseSysCache(contup); + + return visible; +} + +/* * DeconstructQualifiedName * Given a possibly-qualified name expressed as a list of String nodes, * extract the schema name and object name. @@ -1854,3 +1935,11 @@ pg_opclass_is_visible(PG_FUNCTION_ARGS) PG_RETURN_BOOL(OpclassIsVisible(oid)); } + +Datum +pg_conversion_is_visible(PG_FUNCTION_ARGS) +{ + Oid oid = PG_GETARG_OID(0); + + PG_RETURN_BOOL(ConversionIsVisible(oid)); +} |