fix mutex unlock

Author: kevinAlbs

src/libmongoc/src/mongoc/mongoc-read-prefs.c

@@ -378,17 +378,12 @@ assemble_query (const mongoc_read_prefs_t *read_prefs,
       break;
 
    case MONGOC_TOPOLOGY_SHARDED:
+   case MONGOC_TOPOLOGY_LOADBALANCED:
       _apply_read_preferences_mongos (read_prefs, query_bson, result);
       break;
 
    case MONGOC_TOPOLOGY_UNKNOWN:
    case MONGOC_TOPOLOGY_DESCRIPTION_TYPES:
-   case MONGOC_TOPOLOGY_LOADBALANCED:
-   /* TODO (CDRIVER-4056): this is pending a question on pre-5.0 support and testing.
-    * The spec says 5.0 is the minimum server version.
-    * It is unclear if we can assume the backing server always supports OP_MSG.
-    * I think the intent is we can, but there is no max wire version check.
-    */
    default:
       /* must not call _apply_read_preferences with unknown topology type */
       BSON_ASSERT (false);

src/libmongoc/src/mongoc/mongoc-topology.c

@@ -1016,9 +1016,9 @@ mongoc_topology_select_server_id (mongoc_topology_t *topology,
 
          if (!selected_server) {
             _mongoc_server_selection_error (
-                  "No suitable server found in load balanced deployment",
-                  NULL,
-                  error);
+               "No suitable server found in load balanced deployment",
+               NULL,
+               error);
             return 0;
          }
       }
@@ -1123,10 +1123,11 @@ mongoc_topology_select_server_id (mongoc_topology_t *topology,
       if (topology->description.type == MONGOC_TOPOLOGY_LOADBALANCED) {
          /* Bypass server selection loop. Always select the only server. */
          if (!selected_server) {
+            bson_mutex_unlock (&topology->mutex);
             _mongoc_server_selection_error (
-                  "No suitable server found in load balanced deployment",
-                  NULL,
-                  error);
+               "No suitable server found in load balanced deployment",
+               NULL,
+               error);
             return 0;
          }
       }

src/libmongoc/tests/test-mongoc-loadbalanced.c

@@ -20,7 +20,9 @@
 #include "test-libmongoc.h"
 #include "TestSuite.h"
 
-static char *loadbalanced_uri (void) {
+static char *
+loadbalanced_uri (void)
+{
    return test_framework_getenv ("SINGLE_MONGOS_LB_URI");
 }
 
@@ -65,7 +67,8 @@ test_loadbalanced_sessions_do_not_expire (void *unused)
    mongoc_client_session_destroy (session);
 
    if (!bson_equal (lsid1, lsid2)) {
-      test_error ("Session not reused: %s != %s", tmp_json (lsid1), tmp_json (lsid2));
+      test_error (
+         "Session not reused: %s != %s", tmp_json (lsid1), tmp_json (lsid2));
    }
 
    bson_destroy (lsid1);
@@ -77,23 +80,24 @@ test_loadbalanced_sessions_do_not_expire (void *unused)
 static int
 skip_if_not_loadbalanced (void)
 {
-   char *val = loadbalanced_uri ();
-   if (!val) {
+   if (test_framework_getenv_bool ("MONGOC_TEST_LOADBALANCED")) {
+      return 1;
+   } else {
       return 0;
    }
-   bson_free (val);
-   return 1;
 }
 
 void
 test_loadbalanced_install (TestSuite *suite)
 {
-   TestSuite_AddFull (suite, "/loadbalanced/sessions/supported",
+   TestSuite_AddFull (suite,
+                      "/loadbalanced/sessions/supported",
                       test_loadbalanced_sessions_supported,
                       NULL /* ctx */,
                       NULL /* dtor */,
                       skip_if_not_loadbalanced);
-   TestSuite_AddFull (suite, "/loadbalanced/sessions/do_not_expire",
+   TestSuite_AddFull (suite,
+                      "/loadbalanced/sessions/do_not_expire",
                       test_loadbalanced_sessions_do_not_expire,
                       NULL /* ctx */,
                       NULL /* dtor */,

src/libmongoc/tests/test-mongoc-sdam.c

@@ -35,10 +35,12 @@ _topology_has_description (mongoc_topology_description_t *topology,
             BSON_ASSERT (sd->set_name);
             ASSERT_CMPSTR (sd->set_name, set_name);
          }
-         /* TODO (CDRIVER-4057) this should assert that a null setName means the server description also has no setName.
+         /* TODO (CDRIVER-4057) this should assert that a null setName means the
+         server description also has no setName.
             Uncomment this when CDRIVER-4057 is resolved.
          else if (sd->set_name) {
-            test_error ("server: %s, expected NULL setName, got: %s", address, sd->set_name);
+            test_error ("server: %s, expected NULL setName, got: %s", address,
+         sd->set_name);
          }
          */
       } else if (strcmp ("type", bson_iter_key (&server_iter)) == 0) {