implement compositor create region

Complete the implementation of wlr_region_create and put it in the compositor.

examples/compositor/wl_compositor.c

@@ -3,6 +3,7 @@
 #include <wayland-server.h>
 #include <wlr/util/log.h>
 #include <wlr/types/wlr_surface.h>
+#include <wlr/types/wlr_region.h>
 #include "compositor.h"
 
 static void destroy_surface_listener(struct wl_listener *listener, void *data) {
@@ -31,7 +32,7 @@ static void wl_compositor_create_surface(struct wl_client *client,
 
 static void wl_compositor_create_region(struct wl_client *client,
 		struct wl_resource *resource, uint32_t id) {
-	wlr_log(L_DEBUG, "TODO: implement create_region");
+	wlr_region_create(client, resource, id);
 }
 
 struct wl_compositor_interface wl_compositor_impl = {

include/wlr/types/wlr_region.h

@@ -5,6 +5,7 @@ struct wl_resource;
 
 // Implements the given resource as region.
 // Sets the associated pixman_region32_t as userdata.
-void wlr_region_create(struct wl_resource *res);
+void wlr_region_create(struct wl_client *client, struct wl_resource *res,
+		uint32_t id);
 
 #endif

types/wlr_region.c

@@ -37,8 +37,23 @@ static void destroy_region(struct wl_resource *resource) {
 	free(reg);
 }
 
-void wlr_region_create(struct wl_resource *res) {
+void wlr_region_create(struct wl_client *client, struct wl_resource *res,
+		uint32_t id) {
 	pixman_region32_t *region = calloc(1, sizeof(pixman_region32_t));
+	if (region == NULL) {
+		wl_resource_post_no_memory(res);
+		return;
+	}
+
 	pixman_region32_init(region);
-	wl_resource_set_implementation(res, &region_interface, region, destroy_region);
+
+	struct wl_resource *region_resource = wl_resource_create(client,
+		&wl_region_interface, 1, id);
+	if (region_resource == NULL) {
+		free(region);
+		wl_resource_post_no_memory(res);
+		return;
+	}
+	wl_resource_set_implementation(region_resource, &region_interface, region,
+		destroy_region);
 }