pg_upgrade: error out on 'line' data type usage

The data type internal format changed in 9.4.  Also mention this in the
9.4 release notes.

contrib/pg_upgrade/check.c

@@ -122,6 +122,10 @@ check_and_dump_old_cluster(bool live_check, char **sequence_script_file_name)
 				old_8_3_create_sequence_script(&old_cluster);
 	}
 
+	/* Pre-PG 9.4 had a different 'line' data type internal format */
+	if (GET_MAJOR_VERSION(old_cluster.major_version) <= 904)
+		old_9_3_check_for_line_data_type_usage(&old_cluster);
+
 	/* Pre-PG 9.0 had no large object permissions */
 	if (GET_MAJOR_VERSION(old_cluster.major_version) <= 804)
 		new_9_0_populate_pg_largeobject_metadata(&old_cluster, true);
@@ -914,8 +918,7 @@ check_for_reg_data_type_usage(ClusterInfo *cluster)
 		"			'pg_catalog.regconfig'::pg_catalog.regtype, "
 								"			'pg_catalog.regdictionary'::pg_catalog.regtype) AND "
 								"		c.relnamespace = n.oid AND "
-							  "		n.nspname != 'pg_catalog' AND "
-						 "		n.nspname != 'information_schema'");
+							  "		n.nspname NOT IN ('pg_catalog', 'information_schema')");
 
 		ntups = PQntuples(res);
 		i_nspname = PQfnumber(res, "nspname");

contrib/pg_upgrade/pg_upgrade.h

@@ -470,6 +470,7 @@ void		pg_putenv(const char *var, const char *val);
 
 void new_9_0_populate_pg_largeobject_metadata(ClusterInfo *cluster,
 										 bool check_mode);
+void old_9_3_check_for_line_data_type_usage(ClusterInfo *cluster);
 
 /* version_old_8_3.c */
 

contrib/pg_upgrade/version.c

@@ -87,3 +87,92 @@ new_9_0_populate_pg_largeobject_metadata(ClusterInfo *cluster, bool check_mode)
 	else
 		check_ok();
 }
+
+
+/*
+ * old_9_3_check_for_line_data_type_usage()
+ *	9.3 -> 9.4
+ *	Fully implement the 'line' data type in 9.4, which previously returned
+ *	"not enabled" by default and was only functionally enabled with a 
+ *	compile-time switch;  9.4 "line" has different binary and text
+ *	representation formats;  checks tables and indexes.
+ */
+void
+old_9_3_check_for_line_data_type_usage(ClusterInfo *cluster)
+{
+	int			dbnum;
+	FILE	   *script = NULL;
+	bool		found = false;
+	char		output_path[MAXPGPATH];
+
+	prep_status("Checking for invalid \"line\" user columns");
+
+	snprintf(output_path, sizeof(output_path), "tables_using_line.txt");
+
+	for (dbnum = 0; dbnum < cluster->dbarr.ndbs; dbnum++)
+	{
+		PGresult   *res;
+		bool		db_used = false;
+		int			ntups;
+		int			rowno;
+		int			i_nspname,
+					i_relname,
+					i_attname;
+		DbInfo	   *active_db = &cluster->dbarr.dbs[dbnum];
+		PGconn	   *conn = connectToServer(cluster, active_db->db_name);
+
+		res = executeQueryOrDie(conn,
+								"SELECT n.nspname, c.relname, a.attname "
+								"FROM	pg_catalog.pg_class c, "
+								"		pg_catalog.pg_namespace n, "
+								"		pg_catalog.pg_attribute a "
+								"WHERE	c.oid = a.attrelid AND "
+								"		NOT a.attisdropped AND "
+								"		a.atttypid = 'pg_catalog.line'::pg_catalog.regtype AND "
+								"		c.relnamespace = n.oid AND "
+		/* exclude possible orphaned temp tables */
+								"		n.nspname !~ '^pg_temp_' AND "
+						 "		n.nspname !~ '^pg_toast_temp_' AND "
+								"		n.nspname NOT IN ('pg_catalog', 'information_schema')");
+
+		ntups = PQntuples(res);
+		i_nspname = PQfnumber(res, "nspname");
+		i_relname = PQfnumber(res, "relname");
+		i_attname = PQfnumber(res, "attname");
+		for (rowno = 0; rowno < ntups; rowno++)
+		{
+			found = true;
+			if (script == NULL && (script = fopen_priv(output_path, "w")) == NULL)
+				pg_fatal("could not open file \"%s\": %s\n", output_path, getErrorText(errno));
+			if (!db_used)
+			{
+				fprintf(script, "Database: %s\n", active_db->db_name);
+				db_used = true;
+			}
+			fprintf(script, "  %s.%s.%s\n",
+					PQgetvalue(res, rowno, i_nspname),
+					PQgetvalue(res, rowno, i_relname),
+					PQgetvalue(res, rowno, i_attname));
+		}
+
+		PQclear(res);
+
+		PQfinish(conn);
+	}
+
+	if (script)
+		fclose(script);
+
+	if (found)
+	{
+		pg_log(PG_REPORT, "fatal\n");
+		pg_fatal("Your installation contains the \"line\" data type in user tables.  This\n"
+		"data type changed its internal and input/output format between your old\n"
+				 "and new clusters so this cluster cannot currently be upgraded.  You can\n"
+		"remove the problem tables and restart the upgrade.  A list of the problem\n"
+				 "columns is in the file:\n"
+				 "    %s\n\n", output_path);
+	}
+	else
+		check_ok();
+}

doc/src/sgml/release-9.4.sgml

@@ -1262,7 +1262,8 @@
        <para>
         The line <emphasis>segment</> data type (<link
         linkend="datatype-lseg"><type>LSEG</></link>) has always been
-        fully supported.
+        fully supported.  The previous <type>line</> data type (enabled
+        only via a compile-time option) is not binary or dump-compatible.
        </para>
       </listitem>