tests: Add a test for GFileMonitor deadlocks

This test is opportunistic in that it’s not possible to detect whether
the race condition has been hit (other than by hitting a deadlock).

So the only approach we can take for testing is to loop over the code
which has previously been known to cause a deadlock a number of times.

The number of repetitions is chosen from running the test with the
deadlock fix reverted.

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

Helps: #1941
This commit is contained in:
Philip Withnall 2022-05-30 17:55:43 +01:00
parent 8e9f238667
commit e5a691e84a

View File

@ -1036,6 +1036,57 @@ test_file_hard_links (Fixture *fixture,
g_object_unref (data.output_stream);
}
static void
test_finalize_in_callback (Fixture *fixture,
gconstpointer user_data)
{
GFile *file = NULL;
guint i;
g_test_summary ("Test that finalization of a GFileMonitor in one of its "
"callbacks doesnt cause a deadlock.");
g_test_bug ("https://gitlab.gnome.org/GNOME/glib/-/issues/1941");
file = g_file_get_child (fixture->tmp_dir, "race-file");
for (i = 0; i < 50; i++)
{
GFileMonitor *monitor = NULL;
GError *local_error = NULL;
/* Monitor the file. */
monitor = g_file_monitor_file (file, G_FILE_MONITOR_NONE, NULL, &local_error);
g_assert_no_error (local_error);
g_assert_nonnull (monitor);
/* Create the file. */
g_file_replace_contents (file, "hello", 5, NULL, FALSE,
G_FILE_CREATE_NONE, NULL, NULL, &local_error);
g_assert_no_error (local_error);
/* Immediately drop the last ref to the monitor in the hope that this
* happens in the middle of the critical section in
* g_file_monitor_source_handle_event(), so that any cleanup at the end
* of that function is done with a now-finalised file monitor. */
g_object_unref (monitor);
/* Re-create the monitor and do the same again for deleting the file, to
* give a second chance at hitting the race condition. */
monitor = g_file_monitor_file (file, G_FILE_MONITOR_NONE, NULL, &local_error);
g_assert_no_error (local_error);
g_assert_nonnull (monitor);
/* Delete the file. */
g_file_delete (file, NULL, &local_error);
g_assert_no_error (local_error);
/* Drop the ref again. */
g_object_unref (monitor);
}
g_object_unref (file);
}
int
main (int argc, char *argv[])
{
@ -1047,6 +1098,7 @@ main (int argc, char *argv[])
g_test_add ("/monitor/dir-not-existent", Fixture, NULL, setup, test_dir_non_existent, teardown);
g_test_add ("/monitor/cross-dir-moves", Fixture, NULL, setup, test_cross_dir_moves, teardown);
g_test_add ("/monitor/file/hard-links", Fixture, NULL, setup, test_file_hard_links, teardown);
g_test_add ("/monitor/finalize-in-callback", Fixture, NULL, setup, test_finalize_in_callback, teardown);
return g_test_run ();
}