libweston: add required_capabilities test suite quirk

This allows tests to skip when required capabilities are not present.
The output damage test for the shadow buffer case needs this.

required_capabilities is added to struct weston_testsuite_quirks which
is libweston public API just because there is no better place currently.
This is a little weird because the code to check it is in compositor,
not libweston.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>

compositor/main.c

@@ -816,6 +816,33 @@ weston_compositor_log_capabilities(struct weston_compositor *compositor)
 				"presentation clock resolution: N/A\n");
 }
 
+static bool
+check_compositor_capabilities(struct weston_compositor *compositor,
+			      uint32_t mask)
+{
+	uint32_t missing = mask & ~compositor->capabilities;
+	unsigned i;
+
+	if (missing == 0)
+		return true;
+
+	weston_log("Quirk error, missing capabilities:\n");
+	for (i = 0; i < ARRAY_LENGTH(capability_strings); i++) {
+		if (!(missing & capability_strings[i].bit))
+			continue;
+
+		weston_log_continue(STAMP_SPACE "- %s\n",
+				    capability_strings[i].desc);
+		missing &= ~capability_strings[i].bit;
+	}
+	if (missing) {
+		weston_log_continue(STAMP_SPACE "- unlisted bits 0x%x\n",
+				    missing);
+	}
+
+	return false;
+}
+
 static void
 handle_primary_client_destroyed(struct wl_listener *listener, void *data)
 {
@@ -3355,6 +3382,12 @@ wet_main(int argc, char *argv[], const struct weston_testsuite_data *test_data)
 		goto out;
 	}
 
+	if (!check_compositor_capabilities(wet.compositor,
+				test_data->test_quirks.required_capabilities)) {
+		ret = WET_MAIN_RET_MISSING_CAPS;
+		goto out;
+	}
+
 	weston_compositor_flush_heads_changed(wet.compositor);
 	if (wet.init_failed)
 		goto out;

compositor/weston.h

@@ -95,6 +95,12 @@ text_backend_init(struct weston_compositor *ec);
 void
 text_backend_destroy(struct text_backend *text_backend);
 
+/*
+ * Return value from wet_main() when
+ * weston_testsuite_quirks::required_capabilities are not met.
+ */
+#define WET_MAIN_RET_MISSING_CAPS 77
+
 int
 wet_main(int argc, char *argv[], const struct weston_testsuite_data *test_data);