tests: Add unit tests for GDBusMethodInvocation

These should cover everything to do with returning a value or error from
a `GDBusMethodInvocation` object.

Signed-off-by: Philip Withnall <pwithnall@endlessos.org>

2 files changed, 403 insertions, 0 deletions

diff --git a/gio/tests/gdbus-method-invocation.c b/gio/tests/gdbus-method-invocation.c
new file mode 100644
index 000000000..985fd45ce
--- /dev/null
+++ b/gio/tests/gdbus-method-invocation.c
@@ -0,0 +1,402 @@
+/* GIO - GLib Input, Output and Streaming Library
+ *
+ * Copyright © 2022 Endless OS Foundation, LLC
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General
+ * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#include <gio/gio.h>
+#include <gio/gunixfdlist.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "gdbus-tests.h"
+
+static const GDBusArgInfo foo_get_fds_in_args =
+{
+  -1,
+  "type",
+  "s",
+  NULL
+};
+static const GDBusArgInfo * const foo_get_fds_in_arg_pointers[] = {&foo_get_fds_in_args, NULL};
+
+static const GDBusArgInfo foo_get_fds_out_args =
+{
+  -1,
+  "some_fd",
+  "h",
+  NULL
+};
+static const GDBusArgInfo * const foo_get_fds_out_arg_pointers[] = {&foo_get_fds_out_args, NULL};
+
+static const GDBusMethodInfo foo_method_info_wrong_return_type =
+{
+  -1,
+  "WrongReturnType",
+  NULL,  /* in args */
+  NULL,  /* out args */
+  NULL  /* annotations */
+};
+static const GDBusMethodInfo foo_method_info_close_before_returning =
+{
+  -1,
+  "CloseBeforeReturning",
+  NULL,  /* in args */
+  NULL,  /* out args */
+  NULL  /* annotations */
+};
+static const GDBusMethodInfo foo_method_info_get_fds =
+{
+  -1,
+  "GetFDs",
+  (GDBusArgInfo **) foo_get_fds_in_arg_pointers,
+  (GDBusArgInfo **) foo_get_fds_out_arg_pointers,
+  NULL  /* annotations */
+};
+static const GDBusMethodInfo foo_method_info_return_error =
+{
+  -1,
+  "ReturnError",
+  NULL,  /* in args */
+  NULL,  /* out args */
+  NULL  /* annotations */
+};
+static const GDBusMethodInfo * const foo_method_info_pointers[] = {
+  &foo_method_info_wrong_return_type,
+  &foo_method_info_close_before_returning,
+  &foo_method_info_get_fds,
+  &foo_method_info_return_error,
+  NULL
+};
+
+static const GDBusPropertyInfo foo_property_info[] =
+{
+  {
+    -1,
+    "InvalidType",
+    "s",
+    G_DBUS_PROPERTY_INFO_FLAGS_READABLE | G_DBUS_PROPERTY_INFO_FLAGS_WRITABLE,
+    NULL
+  },
+  {
+    -1,
+    "InvalidTypeNull",
+    "s",
+    G_DBUS_PROPERTY_INFO_FLAGS_READABLE | G_DBUS_PROPERTY_INFO_FLAGS_WRITABLE,
+    NULL
+  },
+  {
+    -1,
+    "InvalidValueType",
+    "s",
+    G_DBUS_PROPERTY_INFO_FLAGS_READABLE | G_DBUS_PROPERTY_INFO_FLAGS_WRITABLE,
+    NULL
+  },
+};
+static const GDBusPropertyInfo * const foo_property_info_pointers[] =
+{
+  &foo_property_info[0],
+  &foo_property_info[1],
+  &foo_property_info[2],
+  NULL
+};
+
+static const GDBusInterfaceInfo foo_interface_info =
+{
+  -1,
+  "org.example.Foo",
+  (GDBusMethodInfo **) &foo_method_info_pointers,
+  NULL,  /* signals */
+  (GDBusPropertyInfo **) &foo_property_info_pointers,
+  NULL,  /* annotations */
+};
+
+/* ---------------------------------------------------------------------------------------------------- */
+
+static void
+test_method_invocation_return_method_call (GDBusConnection       *connection,
+                                           const gchar           *sender,
+                                           const gchar           *object_path,
+                                           const gchar           *interface_name,
+                                           const gchar           *method_name,
+                                           GVariant              *parameters,
+                                           GDBusMethodInvocation *invocation,
+                                           gpointer               user_data)
+{
+  gboolean no_reply = g_dbus_message_get_flags (g_dbus_method_invocation_get_message (invocation)) & G_DBUS_MESSAGE_FLAGS_NO_REPLY_EXPECTED;
+
+  if (g_str_equal (interface_name, "org.freedesktop.DBus.Properties") &&
+      g_str_equal (method_name, "Get"))
+    {
+      const gchar *iface_name, *prop_name;
+
+      g_variant_get (parameters, "(&s&s)", &iface_name, &prop_name);
+      g_assert_cmpstr (iface_name, ==, "org.example.Foo");
+
+      /* Do different things depending on the property name. */
+      if (g_str_equal (prop_name, "InvalidType"))
+        {
+          if (!no_reply)
+            g_test_expect_message ("GLib-GIO", G_LOG_LEVEL_WARNING,
+                                   "Type of return value for property 'Get' call should be '(v)' but got '(s)'");
+          g_dbus_method_invocation_return_value (invocation, g_variant_new ("(s)", "this type is invalid"));
+        }
+      else if (g_str_equal (prop_name, "InvalidTypeNull"))
+        {
+          if (!no_reply)
+            g_test_expect_message ("GLib-GIO", G_LOG_LEVEL_WARNING,
+                                   "Type of return value for property 'Get' call should be '(v)' but got '()'");
+          g_dbus_method_invocation_return_value (invocation, NULL);
+        }
+      else if (g_str_equal (prop_name, "InvalidValueType"))
+        {
+          if (!no_reply)
+            g_test_expect_message ("GLib-GIO", G_LOG_LEVEL_WARNING,
+                                   "Value returned from property 'Get' call for 'InvalidValueType' should be 's' but is 'u'");
+          g_dbus_method_invocation_return_value (invocation, g_variant_new ("(v)", g_variant_new_uint32 (123)));
+        }
+      else
+        {
+          g_assert_not_reached ();
+        }
+
+      g_test_assert_expected_messages ();
+    }
+  else if (g_str_equal (interface_name, "org.freedesktop.DBus.Properties") &&
+           g_str_equal (method_name, "Set"))
+    {
+      const gchar *iface_name, *prop_name;
+      GVariant *value;
+
+      g_variant_get (parameters, "(&s&sv)", &iface_name, &prop_name, &value);
+      g_assert_cmpstr (iface_name, ==, "org.example.Foo");
+
+      if (g_str_equal (prop_name, "InvalidType"))
+        {
+          if (!no_reply)
+            g_test_expect_message ("GLib-GIO", G_LOG_LEVEL_WARNING,
+                                   "Type of return value for property 'Set' call should be '()' but got '(s)'");
+          g_dbus_method_invocation_return_value (invocation, g_variant_new ("(s)", "should be unit"));
+        }
+      else
+        {
+          g_assert_not_reached ();
+        }
+
+      g_test_assert_expected_messages ();
+      g_variant_unref (value);
+    }
+  else if (g_str_equal (interface_name, "org.freedesktop.DBus.Properties") &&
+           g_str_equal (method_name, "GetAll"))
+    {
+      const gchar *iface_name;
+
+      g_variant_get (parameters, "(&s)", &iface_name);
+      g_assert_cmpstr (iface_name, ==, "org.example.Foo");
+
+      if (!no_reply)
+        g_test_expect_message ("GLib-GIO", G_LOG_LEVEL_WARNING,
+                               "Type of return value for property 'GetAll' call should be '(a{sv})' but got '(s)'");
+      g_dbus_method_invocation_return_value (invocation, g_variant_new ("(s)", "should be a different type"));
+    }
+  else if (g_str_equal (interface_name, "org.example.Foo") &&
+           g_str_equal (method_name, "WrongReturnType"))
+    {
+      if (!no_reply)
+        g_test_expect_message ("GLib-GIO", G_LOG_LEVEL_WARNING,
+                               "Type of return value is incorrect: expected '()', got '(s)'");
+      g_dbus_method_invocation_return_value (invocation, g_variant_new ("(s)", "should be a different type"));
+    }
+  else if (g_str_equal (interface_name, "org.example.Foo") &&
+           g_str_equal (method_name, "CloseBeforeReturning"))
+    {
+      g_dbus_connection_close (connection, NULL, NULL, NULL);
+
+      g_dbus_method_invocation_return_value (invocation, NULL);
+    }
+  else if (g_str_equal (interface_name, "org.example.Foo") &&
+           g_str_equal (method_name, "GetFDs"))
+    {
+      const gchar *action;
+      GUnixFDList *list = NULL;
+      GError *local_error = NULL;
+
+      g_variant_get (parameters, "(&s)", &action);
+
+      list = g_unix_fd_list_new ();
+      g_unix_fd_list_append (list, 1, &local_error);
+      g_assert_no_error (local_error);
+
+      if (g_str_equal (action, "WrongNumber"))
+        {
+          g_unix_fd_list_append (list, 1, &local_error);
+          g_assert_no_error (local_error);
+        }
+
+      if (g_str_equal (action, "Valid") ||
+          g_str_equal (action, "WrongNumber"))
+        g_dbus_method_invocation_return_value_with_unix_fd_list (invocation, g_variant_new ("(h)"), list);
+      else
+        g_assert_not_reached ();
+
+      g_object_unref (list);
+    }
+  else if (g_str_equal (interface_name, "org.example.Foo") &&
+           g_str_equal (method_name, "ReturnError"))
+    {
+      g_dbus_method_invocation_return_dbus_error (invocation, "org.example.Foo", "SomeError");
+    }
+  else
+    g_assert_not_reached ();
+}
+
+static void
+ensure_result_cb (GObject      *source,
+                  GAsyncResult *result,
+                  gpointer      user_data)
+{
+  GDBusConnection *connection = G_DBUS_CONNECTION (source);
+  GVariant *reply;
+  guint *n_outstanding_calls = user_data;
+
+  reply = g_dbus_connection_call_finish (connection, result, NULL);
+
+  /* We don’t care what the reply is. */
+  g_clear_pointer (&reply, g_variant_unref);
+
+  g_assert_cmpint (*n_outstanding_calls, >, 0);
+  *n_outstanding_calls = *n_outstanding_calls - 1;
+}
+
+static void
+test_method_invocation_return (void)
+{
+  GDBusConnection *connection = NULL;
+  GError *local_error = NULL;
+  guint registration_id;
+  const GDBusInterfaceVTable vtable = {
+    test_method_invocation_return_method_call, NULL, NULL, { 0 }
+  };
+  guint n_outstanding_calls = 0;
+
+  g_test_summary ("Test calling g_dbus_method_invocation_return_*() in various ways");
+
+  /* Connect to the bus. */
+  connection = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, &local_error);
+  g_assert_no_error (local_error);
+  g_assert_nonnull (connection);
+
+  /* Register an object which we can call methods on. */
+  registration_id = g_dbus_connection_register_object (connection,
+                                                       "/foo",
+                                                       (GDBusInterfaceInfo *) &foo_interface_info,
+                                                       &vtable, NULL, NULL, &local_error);
+  g_assert_no_error (local_error);
+  g_assert_cmpint (registration_id, !=, 0);
+
+  /* Test a variety of error cases */
+    {
+      const struct
+        {
+          const gchar *interface_name;
+          const gchar *method_name;
+          const gchar *parameters_string;
+          gboolean tests_undefined_behaviour;
+        }
+      calls[] =
+        {
+          { "org.freedesktop.DBus.Properties", "Get", "('org.example.Foo', 'InvalidType')", TRUE },
+          { "org.freedesktop.DBus.Properties", "Get", "('org.example.Foo', 'InvalidTypeNull')", TRUE },
+          { "org.freedesktop.DBus.Properties", "Get", "('org.example.Foo', 'InvalidValueType')", TRUE },
+          { "org.freedesktop.DBus.Properties", "Set", "('org.example.Foo', 'InvalidType', <'irrelevant'>)", TRUE },
+          { "org.freedesktop.DBus.Properties", "GetAll", "('org.example.Foo',)", TRUE },
+          { "org.example.Foo", "WrongReturnType", "()", TRUE },
+          { "org.example.Foo", "GetFDs", "('Valid',)", FALSE },
+          { "org.example.Foo", "GetFDs", "('WrongNumber',)", TRUE },
+          { "org.example.Foo", "ReturnError", "()", FALSE },
+          { "org.example.Foo", "CloseBeforeReturning", "()", FALSE },
+        };
+      gsize i;
+
+      for (i = 0; i < G_N_ELEMENTS (calls); i++)
+        {
+          if (calls[i].tests_undefined_behaviour && !g_test_undefined ())
+            {
+              g_test_message ("Skipping %s.%s", calls[i].interface_name, calls[i].method_name);
+              continue;
+            }
+          else
+            {
+              g_test_message ("Calling %s.%s", calls[i].interface_name, calls[i].method_name);
+            }
+
+          /* Call twice, once expecting a result and once not. Do the call which
+           * doesn’t expect a result first; message ordering should ensure that
+           * it’s completed by the time the second call completes, so we don’t
+           * have to account for it separately.
+           *
+           * That’s good, because the only way to get g_dbus_connection_call()
+           * to set %G_DBUS_MESSAGE_FLAGS_NO_REPLY_EXPECTED is to not provide
+           * a callback function. */
+          n_outstanding_calls++;
+
+          g_dbus_connection_call (connection,
+                                  g_dbus_connection_get_unique_name (connection),
+                                  "/foo",
+                                  calls[i].interface_name,
+                                  calls[i].method_name,
+                                  g_variant_new_parsed (calls[i].parameters_string),
+                                  NULL,
+                                  G_DBUS_CALL_FLAGS_NONE,
+                                  -1,
+                                  NULL,
+                                  NULL,  /* no callback */
+                                  NULL);
+
+          g_dbus_connection_call (connection,
+                                  g_dbus_connection_get_unique_name (connection),
+                                  "/foo",
+                                  calls[i].interface_name,
+                                  calls[i].method_name,
+                                  g_variant_new_parsed (calls[i].parameters_string),
+                                  NULL,
+                                  G_DBUS_CALL_FLAGS_NONE,
+                                  -1,
+                                  NULL,
+                                  ensure_result_cb,
+                                  &n_outstanding_calls);
+        }
+    }
+
+  /* Wait until all the calls are complete. */
+  while (n_outstanding_calls > 0)
+    g_main_context_iteration (NULL, TRUE);
+
+  g_dbus_connection_unregister_object (connection, registration_id);
+  g_object_unref (connection);
+}
+
+int
+main (int   argc,
+      char *argv[])
+{
+  g_test_init (&argc, &argv, G_TEST_OPTION_ISOLATE_DIRS, NULL);
+
+  g_test_add_func ("/gdbus/method-invocation/return", test_method_invocation_return);
+
+  return session_bus_run ();
+}
diff --git a/gio/tests/meson.build b/gio/tests/meson.build
index 81ff551dd..c825b0cd7 100644
--- a/gio/tests/meson.build
+++ b/gio/tests/meson.build
@@ -333,6 +333,7 @@ if host_machine.system() != 'windows'
         'suite' : ['slow'],
       },
       'gdbus-introspection' : {'extra_sources' : extra_sources},
+      'gdbus-method-invocation' : {'extra_sources' : extra_sources},
       'gdbus-names' : {'extra_sources' : extra_sources},
       'gdbus-proxy' : {'extra_sources' : extra_sources},
       'gdbus-proxy-threads' : {