diff options
Diffstat (limited to 'contrib/dblink/dblink.c')
| -rw-r--r-- | contrib/dblink/dblink.c | 85 |
1 files changed, 84 insertions, 1 deletions
diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c index 6f3cc71f166..ccf8cb2a87d 100644 --- a/contrib/dblink/dblink.c +++ b/contrib/dblink/dblink.c @@ -8,7 +8,7 @@ * Darko Prenosil <Darko.Prenosil@finteh.hr> * Shridhar Daithankar <shridhar_daithankar@persistent.co.in> * - * $PostgreSQL: pgsql/contrib/dblink/dblink.c,v 1.82 2009/06/11 14:48:50 momjian Exp $ + * $PostgreSQL: pgsql/contrib/dblink/dblink.c,v 1.83 2009/08/05 16:11:07 joe Exp $ * Copyright (c) 2001-2009, PostgreSQL Global Development Group * ALL RIGHTS RESERVED; * @@ -1635,6 +1635,89 @@ dblink_current_query(PG_FUNCTION_ARGS) PG_RETURN_DATUM(current_query(fcinfo)); } +/* + * Retrieve async notifications for a connection. + * + * Returns an setof record of notifications, or an empty set if none recieved. + * Can optionally take a named connection as parameter, but uses the unnamed connection per default. + * + */ +#define DBLINK_NOTIFY_COLS 3 + +PG_FUNCTION_INFO_V1(dblink_get_notify); +Datum +dblink_get_notify(PG_FUNCTION_ARGS) +{ + PGconn *conn = NULL; + remoteConn *rconn = NULL; + PGnotify *notify; + ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo; + TupleDesc tupdesc; + Tuplestorestate *tupstore; + MemoryContext per_query_ctx; + MemoryContext oldcontext; + + DBLINK_INIT; + if (PG_NARGS() == 1) + DBLINK_GET_NAMED_CONN; + else + conn = pconn->conn; + + /* create the tuplestore */ + per_query_ctx = rsinfo->econtext->ecxt_per_query_memory; + oldcontext = MemoryContextSwitchTo(per_query_ctx); + + tupdesc = CreateTemplateTupleDesc(DBLINK_NOTIFY_COLS, false); + TupleDescInitEntry(tupdesc, (AttrNumber) 1, "notify_name", + TEXTOID, -1, 0); + TupleDescInitEntry(tupdesc, (AttrNumber) 2, "be_pid", + INT4OID, -1, 0); + TupleDescInitEntry(tupdesc, (AttrNumber) 3, "extra", + TEXTOID, -1, 0); + + tupstore = tuplestore_begin_heap(true, false, work_mem); + rsinfo->returnMode = SFRM_Materialize; + rsinfo->setResult = tupstore; + rsinfo->setDesc = tupdesc; + + MemoryContextSwitchTo(oldcontext); + + PQconsumeInput(conn); + while ((notify = PQnotifies(conn)) != NULL) + { + Datum values[DBLINK_NOTIFY_COLS]; + bool nulls[DBLINK_NOTIFY_COLS]; + + memset(values, 0, sizeof(values)); + memset(nulls, 0, sizeof(nulls)); + + if (notify->relname != NULL) + values[0] = CStringGetTextDatum(notify->relname); + else + nulls[0] = true; + + values[1] = Int32GetDatum(notify->be_pid); + + if (notify->extra != NULL) + values[2] = CStringGetTextDatum(notify->extra); + else + nulls[2] = true; + + /* switch to appropriate context while storing the tuple */ + MemoryContextSwitchTo(per_query_ctx); + tuplestore_putvalues(tupstore, tupdesc, values, nulls); + MemoryContextSwitchTo(oldcontext); + + PQfreemem(notify); + PQconsumeInput(conn); + } + + /* clean up and return the tuplestore */ + tuplestore_donestoring(tupstore); + + return (Datum) 0; +} + /************************************************************* * internal functions */ |