Fix ancient connection leak in dblink

jconway · jconway · commit 8469923f3ea8 · 2017-03-11T13:32:26.000-08:00
When using unnamed connections with dblink, every time a new connection is made, the old one is leaked. Fix that. This has been an issue probably since dblink was first committed. Someone complained almost ten years ago, but apparently I decided not to pursue it at the time, and neither did anyone else, so it slipped between the cracks. Now that someone else has complained, fix in all supported branches. Discussion: (orig) https://postgr.es/m/flat/F680AB59-6D6F-4026-9599-1BE28880273D%40decibel.org#F680AB59-6D6F-4026-9599-1BE28880273D@decibel.org Discussion: (new) https://postgr.es/m/flat/0A3221C70F24FB45833433255569204D1F6ADF8C@G01JPEXMBYT05 Reported by: Jim Nasby and Takayuki Tsunakawa
diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
@@ -301,7 +301,11 @@ dblink_connect(PG_FUNCTION_ARGS)
 		createNewConnection(connname, rconn);
 	}
 	else
+	{
+		if (pconn->conn)
+			PQfinish(pconn->conn);
 		pconn->conn = conn;
+	}
 
 	PG_RETURN_TEXT_P(cstring_to_text("OK"));
 }

Original file line number	Diff line number	Diff line change
`@@ -301,7 +301,11 @@ dblink_connect(PG_FUNCTION_ARGS)`
`301`	`301`	`createNewConnection(connname, rconn);`
`302`	`302`	`}`
`303`	`303`	`else`
	`304`	`+ {`
	`305`	`+ if (pconn->conn)`
	`306`	`+ PQfinish(pconn->conn);`
`304`	`307`	`pconn->conn = conn;`
	`308`	`+ }`
`305`	`309`
`306`	`310`	`PG_RETURN_TEXT_P(cstring_to_text("OK"));`
`307`	`311`	`}`