xwm: set the right cursor when hovering on the decoration borders

use the alternative cursor names used also in window.c, since the
names it used previously are not guaranteed to exist in all themes.

src/xwayland/window-manager.c

@@ -1283,27 +1283,99 @@ enum cursor_type {
 	XWM_CURSOR_LEFT_PTR,
 };
 
-static const char *cursors[] = {
-	"top_side",
+/*
+ * The following correspondences between file names and cursors was copied
+ * from: https://bugs.kde.org/attachment.cgi?id=67313
+ */
+
+static const char *bottom_left_corners[] = {
+	"bottom_left_corner",
+	"sw-resize",
+	"size_bdiag"
+};
+
+static const char *bottom_right_corners[] = {
+	"bottom_right_corner",
+	"se-resize",
+	"size_fdiag"
+};
+
+static const char *bottom_sides[] = {
 	"bottom_side",
+	"s-resize",
+	"size_ver"
+};
+
+static const char *left_ptrs[] = {
+	"left_ptr",
+	"default",
+	"top_left_arrow",
+	"left-arrow"
+};
+
+static const char *left_sides[] = {
 	"left_side",
+	"w-resize",
+	"size_hor"
+};
+
+static const char *right_sides[] = {
 	"right_side",
+	"e-resize",
+	"size_hor"
+};
+
+static const char *top_left_corners[] = {
 	"top_left_corner",
+	"nw-resize",
+	"size_fdiag"
+};
+
+static const char *top_right_corners[] = {
 	"top_right_corner",
-	"bottom_left_corner",
-	"bottom_right_corner",
-	"left_ptr"
+	"ne-resize",
+	"size_bdiag"
+};
+
+static const char *top_sides[] = {
+	"top_side",
+	"n-resize",
+	"size_ver"
+};
+
+struct cursor_alternatives {
+	const char **names;
+	size_t count;
+};
+
+static const struct cursor_alternatives cursors[] = {
+	{top_sides, ARRAY_LENGTH(top_sides)},
+	{bottom_sides, ARRAY_LENGTH(bottom_sides)},
+	{left_sides, ARRAY_LENGTH(left_sides)},
+	{right_sides, ARRAY_LENGTH(right_sides)},
+	{top_left_corners, ARRAY_LENGTH(top_left_corners)},
+	{top_right_corners, ARRAY_LENGTH(top_right_corners)},
+	{bottom_left_corners, ARRAY_LENGTH(bottom_left_corners)},
+	{bottom_right_corners, ARRAY_LENGTH(bottom_right_corners)},
+	{left_ptrs, ARRAY_LENGTH(left_ptrs)},
 };
 
 static void
 weston_wm_create_cursors(struct weston_wm *wm)
 {
+	const char *name;
 	int i, count = ARRAY_LENGTH(cursors);
+	size_t j;
 
 	wm->cursors = malloc(count * sizeof(xcb_cursor_t));
 	for (i = 0; i < count; i++) {
-		wm->cursors[i] =
-			xcb_cursor_library_load_cursor(wm, cursors[i]);
+		for (j = 0; j < cursors[i].count; j++) {
+			name = cursors[i].names[j];
+			wm->cursors[i] =
+				xcb_cursor_library_load_cursor(wm, name);
+			if (wm->cursors[i] != (xcb_cursor_t)-1)
+				break;
+		}
 	}
 
 	wm->last_cursor = -1;