Some little fixes for bapt’s patch, use predict_text_width, support UTF8, pre-render workspace names

src/workspace.c

@@ -0,0 +1,43 @@
+/*
+ * vim:ts=8:expandtab
+ *
+ * i3 - an improved dynamic tiling window manager
+ *
+ * © 2009 Michael Stapelberg and contributors
+ *
+ * See file LICENSE for license information.
+ *
+ * workspace.c: Functions for modifying workspaces
+ *
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <err.h>
+
+#include "util.h"
+#include "data.h"
+
+/*
+ * Sets the name (or just its number) for the given workspace. This has to
+ * be called for every workspace as the rendering function
+ * (render_internal_bar) relies on workspace->name and workspace->name_len
+ * being ready-to-use.
+ *
+ */
+void workspace_set_name(Workspace *ws, const char *name) {
+        char *label;
+        int ret;
+
+        if (name != NULL)
+                ret = asprintf(&label, "%d: %s", ws->num + 1, name);
+        else ret = asprintf(&label, "%d", ws->num + 1);
+
+        if (ret == -1)
+                errx(1, "asprintf() failed");
+
+        FREE(ws->name);
+
+        ws->name = convert_utf8_to_ucs2(label, &(ws->name_len));
+
+        free(label);
+}