Implement UTF-8-clean window titles

include/data.h

@@ -213,9 +213,8 @@ struct Client {
            reservation */
         int desired_height;
 
-        /* Name */
+        /* Name (= window title) */
         char *name;
-        int name_len;
 
         /* fullscreen is pretty obvious */
         bool fullscreen;

include/util.h

@@ -34,6 +34,7 @@ void *scalloc(size_t size);
 char *sstrdup(const char *str);
 void start_application(const char *command);
 void check_error(xcb_connection_t *conn, xcb_void_cookie_t cookie, char *err_message);
+char *convert_utf8_to_ucs2(char *input, int *real_strlen);
 void remove_client_from_container(xcb_connection_t *conn, Client *client, Container *container);
 void set_focus(xcb_connection_t *conn, Client *client);
 void leave_stack_mode(xcb_connection_t *conn, Container *container);

src/handlers.c

@@ -486,10 +486,8 @@ int handle_windowname_change(void *data, xcb_connection_t *conn, uint8_t state,
         if (client->name != NULL)
                 free(client->name);
 
-        client->name_len = xcb_get_property_value_length(prop);
-        client->name = smalloc(client->name_len);
-        strncpy(client->name, xcb_get_property_value(prop), client->name_len);
-        LOG("rename to \"%.*s\".\n", client->name_len, client->name);
+        asprintf(&(client->name), "%.*s", xcb_get_property_value_length(prop), xcb_get_property_value(prop));
+        LOG("rename to \"%s\".\n", client->name);
 
         if (client->container->mode == MODE_STACK)
                 render_container(conn, client->container);

src/layout.c

@@ -167,11 +167,11 @@ void decorate_window(xcb_connection_t *conn, Client *client, xcb_drawable_t draw
         uint32_t values[] = { text_color, background_color, font->id };
         xcb_change_gc(conn, gc, mask, values);
 
-        /* TODO: utf8? */
-        char *label;
-        asprintf(&label, "%.*s", client->name_len, client->name);
-        xcb_image_text_8(conn, strlen(label), drawable, gc, 3 /* X */, offset + font->height /* Y = baseline of font */, label);
-        free(label);
+        int real_strlen;
+        char *ucs2_label = convert_utf8_to_ucs2(client->name, &real_strlen);
+        xcb_image_text_16(conn, real_strlen, drawable, gc, 3 /* X */,
+                          offset + font->height /* Y = baseline of font */, (xcb_char2b_t*)ucs2_label);
+        free(ucs2_label);
 }
 
 /*

src/mainx.c

@@ -17,6 +17,7 @@
 #include <stdbool.h>
 #include <assert.h>
 #include <limits.h>
+#include <locale.h>
 
 #include <X11/XKBlib.h>
 #include <X11/extensions/XKB.h>
@@ -308,6 +309,8 @@ int main(int argc, char *argv[], char *env[]) {
         xcb_window_t root;
         xcb_intern_atom_cookie_t atom_cookies[NUM_ATOMS];
 
+        setlocale(LC_ALL, "");
+
         /* Disable output buffering to make redirects in .xsession actually useful for debugging */
         if (!isatty(fileno(stdout)))
                 setbuf(stdout, NULL);

src/util.c

@@ -17,6 +17,7 @@
 #include <sys/wait.h>
 #include <stdarg.h>
 #include <assert.h>
+#include <iconv.h>
 
 #include "i3.h"
 #include "data.h"
@@ -25,6 +26,8 @@
 #include "util.h"
 #include "xcb.h"
 
+static iconv_t conversion_descriptor = 0;
+
 int min(int a, int b) {
         return (a < b ? a : b);
 }
@@ -135,6 +138,49 @@ void check_error(xcb_connection_t *conn, xcb_void_cookie_t cookie, char *err_mes
         }
 }
 
+/*
+ * Converts the given string to UCS-2 big endian for use with
+ * xcb_image_text_16(). The amount of real glyphs is stored in real_strlen,
+ * a buffer containing the UCS-2 encoded string (16 bit per glyph) is
+ * returned. It has to be freed when done.
+ *
+ */
+char *convert_utf8_to_ucs2(char *input, int *real_strlen) {
+	size_t input_size = strlen(input) + 1;
+	/* UCS-2 consumes exactly two bytes for each glyph */
+	int buffer_size = input_size * 2;
+	printf("reserving %d bytes\n", buffer_size);
+
+	char *buffer = smalloc(buffer_size);
+	size_t output_size = buffer_size;
+	/* We need to use an additional pointer, because iconv() modifies it */
+	char *output = buffer;
+
+	/* We convert the input into UCS-2 big endian */
+        if (conversion_descriptor == 0) {
+                conversion_descriptor = iconv_open("UCS-2BE", "UTF-8");
+                if (conversion_descriptor == 0) {
+                        fprintf(stderr, "error opening the conversion context\n");
+                        exit(1);
+                }
+        }
+
+	/* Get the conversion descriptor back to original state */
+	iconv(conversion_descriptor, NULL, NULL, NULL, NULL);
+
+	/* Convert our text */
+	int rc = iconv(conversion_descriptor, &input, &input_size, &output, &output_size);
+        if (rc == (size_t)-1) {
+		fprintf(stderr, "Converting to UCS-2 failed\n");
+                perror("erron\n");
+		exit(1);
+	}
+
+	*real_strlen = ((buffer_size - output_size) / 2) - 1;
+
+	return buffer;
+}
+
 /*
  * Removes the given client from the container, either because it will be inserted into another
  * one or because it was unmapped