output-layout: improve API

- wlr_output_layout_add{,_auto}() now return a bool indicating whether
  the function has succeeded.
- wlr_output_layout_move() is removed.

Closes: https://gitlab.freedesktop.org/wlroots/wlroots/-/issues/1083

include/wlr/types/wlr_output_layout.h

@@ -28,7 +28,7 @@ struct wlr_output_layout {
 	struct wl_list outputs;
 
 	struct {
-		struct wl_signal add;
+		struct wl_signal add; // struct wlr_output_layout_output *
 		struct wl_signal change;
 		struct wl_signal destroy;
 	} events;
@@ -77,14 +77,30 @@ struct wlr_output *wlr_output_layout_output_at(
 
 /**
  * Add the output to the layout at the specified coordinates. If the output is
- * already part of the output layout, this moves the output.
+ * already a part of the output layout, it will become manually configured and
+ * will be moved to the specified coordinates.
+ *
+ * Returns true on success, false on a memory allocation error.
  */
-void wlr_output_layout_add(struct wlr_output_layout *layout,
+bool wlr_output_layout_add(struct wlr_output_layout *layout,
 	struct wlr_output *output, int lx, int ly);
 
-void wlr_output_layout_move(struct wlr_output_layout *layout,
-	struct wlr_output *output, int lx, int ly);
+/**
+ * Add the output to the layout as automatically configured. This will place
+ * the output in a sensible location in the layout. The coordinates of
+ * the output in the layout will be adjusted dynamically when the layout
+ * changes. If the output is already a part of the layout, it will become
+ * automatically configured.
+ *
+ * Returns true on success, false on a memory allocation error.
+ */
+bool wlr_output_layout_add_auto(struct wlr_output_layout *layout,
+	struct wlr_output *output);
 
+/**
+ * Remove the output from the layout. If the output is already not a part of
+ * the layout, this function is a no-op.
+ */
 void wlr_output_layout_remove(struct wlr_output_layout *layout,
 	struct wlr_output *output);
 
@@ -117,17 +133,6 @@ void wlr_output_layout_closest_point(struct wlr_output_layout *layout,
 void wlr_output_layout_get_box(struct wlr_output_layout *layout,
 	struct wlr_output *reference, struct wlr_box *dest_box);
 
-/**
-* Add an auto configured output to the layout. This will place the output in a
-* sensible location in the layout. The coordinates of the output in the layout
-* may adjust dynamically when the layout changes. If the output is already in
-* the layout, it will become auto configured. If the position of the output is
-* set such as with wlr_output_layout_move(), the output will become manually
-* configured.
-*/
-void wlr_output_layout_add_auto(struct wlr_output_layout *layout,
-	struct wlr_output *output);
-
 /**
  * Get the output closest to the center of the layout extents.
  */

types/wlr_output_layout.c

@@ -165,28 +165,51 @@ static struct wlr_output_layout_output *output_layout_output_create(
 	return l_output;
 }
 
-void wlr_output_layout_add(struct wlr_output_layout *layout,
-		struct wlr_output *output, int lx, int ly) {
+static bool output_layout_add(struct wlr_output_layout *layout,
+		struct wlr_output *output, int lx, int ly,
+		bool auto_configured) {
 	struct wlr_output_layout_output *l_output =
 		wlr_output_layout_get(layout, output);
 	bool is_new = l_output == NULL;
-	if (!l_output) {
+	if (is_new) {
 		l_output = output_layout_output_create(layout, output);
-		if (!l_output) {
-			wlr_log(WLR_ERROR, "Failed to create wlr_output_layout_output");
-			return;
+		if (l_output == NULL) {
+			return false;
 		}
 	}
 
 	l_output->x = lx;
 	l_output->y = ly;
-	l_output->auto_configured = false;
+	l_output->auto_configured = auto_configured;
+
 	output_layout_reconfigure(layout);
 	output_update_global(output);
 
 	if (is_new) {
 		wl_signal_emit_mutable(&layout->events.add, l_output);
 	}
+
+	return true;
+}
+
+bool wlr_output_layout_add(struct wlr_output_layout *layout,
+		struct wlr_output *output, int lx, int ly) {
+	return output_layout_add(layout, output, lx, ly, false);
+}
+
+bool wlr_output_layout_add_auto(struct wlr_output_layout *layout,
+		struct wlr_output *output) {
+	return output_layout_add(layout, output, 0, 0, true);
+}
+
+void wlr_output_layout_remove(struct wlr_output_layout *layout,
+		struct wlr_output *output) {
+	struct wlr_output_layout_output *l_output =
+		wlr_output_layout_get(layout, output);
+	if (l_output != NULL) {
+		output_layout_output_destroy(l_output);
+		output_layout_reconfigure(layout);
+	}
 }
 
 struct wlr_output_layout_output *wlr_output_layout_get(
@@ -256,30 +279,6 @@ struct wlr_output *wlr_output_layout_output_at(struct wlr_output_layout *layout,
 	return NULL;
 }
 
-void wlr_output_layout_move(struct wlr_output_layout *layout,
-		struct wlr_output *output, int lx, int ly) {
-	struct wlr_output_layout_output *l_output =
-		wlr_output_layout_get(layout, output);
-	if (l_output) {
-		l_output->x = lx;
-		l_output->y = ly;
-		l_output->auto_configured = false;
-		output_layout_reconfigure(layout);
-	} else {
-		wlr_log(WLR_ERROR, "output not found in this layout: %s", output->name);
-	}
-}
-
-void wlr_output_layout_remove(struct wlr_output_layout *layout,
-		struct wlr_output *output) {
-	struct wlr_output_layout_output *l_output =
-		wlr_output_layout_get(layout, output);
-	if (l_output) {
-		output_layout_output_destroy(l_output);
-		output_layout_reconfigure(layout);
-	}
-}
-
 void wlr_output_layout_output_coords(struct wlr_output_layout *layout,
 		struct wlr_output *reference, double *lx, double *ly) {
 	assert(layout && reference);
@@ -381,28 +380,6 @@ void wlr_output_layout_get_box(struct wlr_output_layout *layout,
 	}
 }
 
-void wlr_output_layout_add_auto(struct wlr_output_layout *layout,
-		struct wlr_output *output) {
-	struct wlr_output_layout_output *l_output =
-		wlr_output_layout_get(layout, output);
-	bool is_new = l_output == NULL;
-	if (!l_output) {
-		l_output = output_layout_output_create(layout, output);
-		if (!l_output) {
-			wlr_log(WLR_ERROR, "Failed to create wlr_output_layout_output");
-			return;
-		}
-	}
-
-	l_output->auto_configured = true;
-	output_layout_reconfigure(layout);
-	output_update_global(output);
-
-	if (is_new) {
-		wl_signal_emit_mutable(&layout->events.add, l_output);
-	}
-}
-
 struct wlr_output *wlr_output_layout_get_center_output(
 		struct wlr_output_layout *layout) {
 	if (wl_list_empty(&layout->outputs)) {