tui: add nmt_newt_text_width()

We were using g_utf8_strlen() to measure strings for layout, but that
counts combining marks too, and also fails to deal with "fullwidth"
(ie, double-width) CJK characters.

Add a new utility function to do a better job of this (based on code
from vte), and use it everywhere.

tui/newt/nmt-newt-textbox.c

@@ -95,7 +95,7 @@ nmt_newt_textbox_set_text (NmtNewtTextbox *textbox,
 {
 	NmtNewtTextboxPrivate *priv = NMT_NEWT_TEXTBOX_GET_PRIVATE (textbox);
 	char **lines;
-	int i, len;
+	int i, width;
 
 	if (!text)
 		text = "";
@@ -108,9 +108,9 @@ nmt_newt_textbox_set_text (NmtNewtTextbox *textbox,
 	priv->width = priv->height = 0;
 	lines = g_strsplit (priv->text, "\n", -1);
 	for (i = 0; lines[i]; i++) {
-		len = g_utf8_strlen (lines[i], -1);
+		width = nmt_newt_text_width (lines[i]);
-		if (len > priv->width)
+		if (width > priv->width)
-			priv->width = len;
+			priv->width = width;
 	}
 	g_free (lines);
 	priv->height = MIN (i, 1);

tui/newt/nmt-newt-utils.c

@@ -259,6 +259,37 @@ nmt_newt_locale_from_utf8 (const char *str_utf8)
 	return str_lc;
 }
 
+/**
+ * nmt_newt_text_width
+ * @str: a UTF-8 string
+ *
+ * Computes the width (in terminal columns) of @str.
+ *
+ * Returns: the width of @str
+ */
+int
+nmt_newt_text_width (const char *str)
+{
+	int width;
+	gunichar ch;
+
+	for (width = 0; *str; str = g_utf8_next_char (str)) {
+		ch = g_utf8_get_char (str);
+
+		/* Based on _vte_iso2022_unichar_width */
+		if (G_LIKELY (ch < 0x80))
+			width += 1;
+		else if (G_UNLIKELY (g_unichar_iszerowidth (ch)))
+			width += 0;
+		else if (G_UNLIKELY (g_unichar_iswide (ch)))
+			width += 2;
+		else
+			width += 1;
+	}
+
+	return width;
+}
+
 /**
  * nmt_newt_edit_string:
  * @data: data to edit

tui/newt/nmt-newt-utils.h

@@ -37,6 +37,8 @@ typedef enum {
 char *nmt_newt_locale_to_utf8   (const char *str_lc);
 char *nmt_newt_locale_from_utf8 (const char *str_utf8);
 
+int   nmt_newt_text_width       (const char *str);
+
 void nmt_newt_message_dialog  (const char *message,
                                ...);
 int  nmt_newt_choice_dialog (const char *button1,

tui/nmt-connect-connection-list.c

@@ -436,7 +436,7 @@ nmt_connect_connection_list_rebuild (NmtConnectConnectionList *list)
 		for (citer = nmtdev->conns; citer; citer = citer->next) {
 			nmtconn = citer->data;
 
-			max_width = MAX (max_width, g_utf8_strlen (nmtconn->name, -1));
+			max_width = MAX (max_width, nmt_newt_text_width (nmtconn->name));
 		}
 	}
 
@@ -477,7 +477,7 @@ nmt_connect_connection_list_rebuild (NmtConnectConnectionList *list)
 			row = g_strdup_printf ("%c %s%-*s%s",
 			                       active_col,
 			                       nmtconn->name,
-			                       (int)(max_width - g_utf8_strlen (nmtconn->name, -1)), "",
+			                       (int)(max_width - nmt_newt_text_width (nmtconn->name)), "",
 			                       strength_col);
 
 			nmt_newt_listbox_append (listbox, row, nmtconn);

tui/nmt-route-table.c

@@ -211,13 +211,13 @@ nmt_route_table_init (NmtRouteTable *table)
 	NmtRouteTablePrivate *priv = NMT_ROUTE_TABLE_GET_PRIVATE (table);
 	NmtNewtWidget *header, *empty;
 	NmtNewtWidget *dest_prefix_label, *next_hop_label, *metric_label;
-	int dest_prefix_len, next_hop_len, metric_len;
+	int dest_prefix_width, next_hop_width, metric_width;
 	char *text;
 
 	header = nmt_newt_grid_new ();
 
 	text = g_strdup_printf ("%s/%s", _("Destination"), _("Prefix"));
-	dest_prefix_len = g_utf8_strlen (text, -1);
+	dest_prefix_width = nmt_newt_text_width (text);
 	dest_prefix_label = g_object_new (NMT_TYPE_NEWT_LABEL,
 	                                  "text", text,
 	                                  "style", NMT_NEWT_LABEL_PLAIN,
@@ -230,7 +230,7 @@ nmt_route_table_init (NmtRouteTable *table)
 	                               "text", text,
 	                               "style", NMT_NEWT_LABEL_PLAIN,
 	                               NULL);
-	next_hop_len = g_utf8_strlen (text, -1);
+	next_hop_width = nmt_newt_text_width (text);
 	nmt_newt_grid_add (NMT_NEWT_GRID (header), next_hop_label, 1, 0);
 
 	text = _("Metric");
@@ -238,18 +238,18 @@ nmt_route_table_init (NmtRouteTable *table)
 	                             "text", text,
 	                             "style", NMT_NEWT_LABEL_PLAIN,
 	                             NULL);
-	metric_len = g_utf8_strlen (text, -1);
+	metric_width = nmt_newt_text_width (text);
 	nmt_newt_grid_add (NMT_NEWT_GRID (header), metric_label, 2, 0);
 
-	priv->ip_entry_width = MAX (20, MAX (dest_prefix_len, next_hop_len));
+	priv->ip_entry_width = MAX (20, MAX (dest_prefix_width, next_hop_width));
-	priv->metric_entry_width = MAX (7, metric_len);
+	priv->metric_entry_width = MAX (7, metric_width);
 
 	nmt_newt_widget_set_padding (dest_prefix_label,
-	                           0, 0, priv->ip_entry_width - dest_prefix_len, 0);
+	                           0, 0, priv->ip_entry_width - dest_prefix_width, 0);
 	nmt_newt_widget_set_padding (next_hop_label,
-	                           2, 0, priv->ip_entry_width - next_hop_len, 0);
+	                           2, 0, priv->ip_entry_width - next_hop_width, 0);
 	nmt_newt_widget_set_padding (metric_label,
-	                           2, 0, priv->metric_entry_width - metric_len, 0);
+	                           2, 0, priv->metric_entry_width - metric_width, 0);
 
 	nmt_newt_grid_add (NMT_NEWT_GRID (table), header, 0, 0);
 

tui/nmtui-connect.c

@@ -193,15 +193,15 @@ listbox_active_changed (GObject    *object,
 	gboolean has_selection;
 
 	if (G_UNLIKELY (activate == NULL)) {
-		int activate_len, deactivate_len;
+		int activate_width, deactivate_width;
 
 		activate = _("Activate");
-		activate_len = g_utf8_strlen (activate, -1);
+		activate_width = nmt_newt_text_width (activate);
 		deactivate = _("Deactivate");
-		deactivate_len = g_utf8_strlen (deactivate, -1);
+		deactivate_width = nmt_newt_text_width (deactivate);
 
-		activate_padding = MAX (0, deactivate_len - activate_len);
+		activate_padding = MAX (0, deactivate_width - activate_width);
-		deactivate_padding = MAX (0, activate_len - deactivate_len);
+		deactivate_padding = MAX (0, activate_width - deactivate_width);
 	}
 
 	has_selection = nmt_connect_connection_list_get_selection (list, NULL, NULL, NULL, &ac);

tui/nmtui.c

@@ -164,7 +164,7 @@ usage (void)
 	g_printerr ("%s: nmtui\n", usage);
 	for (i = 0; i < num_subprograms; i++) {
 		g_printerr ("%*s  nmtui %s [%s]\n",
-		            (int) g_utf8_strlen (usage, -1), " ",
+		            nmt_newt_text_width (usage), " ",
 		            subprograms[i].name,
 		            _(subprograms[i].arg));
 	}