ovsdb-client: Fix needs-conversion when SERVER is explicitly specified.

When you try to specify `SERVER` to the 'ovsdb-client needs-conversion'
command, it interprets the `SERVER` parameter as the path to the schema
and returns an error.
This PR fixes it.

Fixes: 1b1d2e6 ("ovsdb: Introduce experimental support for clustered databases.")
Submitted-at: #347
Signed-off-by: Alexey Roytman <roytman@il.ibm.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>

ovsdb/ovsdb-client.c

@@ -1573,14 +1573,15 @@ static void
 do_needs_conversion(struct jsonrpc *rpc, const char *database_ OVS_UNUSED,
                     int argc OVS_UNUSED, char *argv[])
 {
+    const char *schema_file_name = argv[argc - 1];
     struct ovsdb_schema *schema1;
-    check_ovsdb_error(ovsdb_schema_from_file(argv[0], &schema1));
+    check_ovsdb_error(ovsdb_schema_from_file(schema_file_name, &schema1));
 
     char *database = schema1->name;
     open_rpc(1, NEED_DATABASE, argc, argv, &rpc, &database);
 
     if (is_database_clustered(rpc, database)) {
-        ovsdb_schema_persist_ephemeral_columns(schema1, argv[0]);
+        ovsdb_schema_persist_ephemeral_columns(schema1, schema_file_name);
     }
 
     struct ovsdb_schema *schema2 = fetch_schema(rpc, schema1->name);

tests/ovsdb-client.at

@@ -12,6 +12,30 @@ AT_CHECK([ovsdb-client get-schema-cksum unix:socket ordinals], [0], [12345678 9
 OVSDB_SERVER_SHUTDOWN
 AT_CLEANUP
 
+AT_SETUP([ovsdb-client needs-conversion (no conversion needed)])
+AT_KEYWORDS([ovsdb client file positive])
+ordinal_schema > schema
+touch .db.~lock~
+AT_CHECK([ovsdb-tool create db schema], [0], [], [ignore])
+AT_CHECK([ovsdb-server --detach --no-chdir --pidfile --remote=punix:socket db], [0], [ignore], [ignore])
+AT_CHECK([ovsdb-client needs-conversion unix:socket schema], [0], [no
+])
+OVSDB_SERVER_SHUTDOWN
+AT_CLEANUP
+
+AT_SETUP([ovsdb-client needs-conversion (conversion needed)])
+AT_KEYWORDS([ovsdb client file positive])
+ordinal_schema > schema
+touch .db.~lock~
+AT_CHECK([ovsdb-tool create db schema], [0], [], [ignore])
+AT_CHECK([ovsdb-server --detach --no-chdir --pidfile --remote=punix:socket db], [0], [ignore], [ignore])
+sed 's/5\.1\.3/5.1.4/' < schema > schema2
+AT_CHECK([diff schema schema2], [1], [ignore])
+AT_CHECK([ovsdb-client needs-conversion unix:socket schema2], [0], [yes
+])
+OVSDB_SERVER_SHUTDOWN
+AT_CLEANUP
+
 AT_SETUP([ovsdb-client backup and restore])
 AT_KEYWORDS([ovsdb client positive])