diff --git a/src/perl/common/Core.xs b/src/perl/common/Core.xs
index 5d2f7bca..7c72f646 100644
--- a/src/perl/common/Core.xs
+++ b/src/perl/common/Core.xs
@@ -2,6 +2,8 @@
 #include "module.h"
 #include "irssi-version.h"
 #include "core.h"
+#include "utf8.h"
+#include "recode.h"
 
 #include "pidwait.h"
 #include "session.h"
@@ -687,6 +689,25 @@ CODE:
 OUTPUT:
 	RETVAL
 
+int
+string_width(str)
+	char *str
+C_ARGS:
+	str, is_utf8() ? TREAT_STRING_AS_UTF8 : TREAT_STRING_AS_BYTES
+
+void
+string_chars_for_width(str, width)
+	char *str
+	unsigned int width
+PREINIT:
+	int retval;
+	unsigned int bytes;
+PPCODE:
+	retval = string_chars_for_width(str, is_utf8() ? TREAT_STRING_AS_UTF8 : TREAT_STRING_AS_BYTES, width, &bytes);
+	mXPUSHi(retval);
+	mXPUSHu(bytes);
+
+
 #*******************************
 MODULE = Irssi::Core	PACKAGE = Irssi::Server
 #*******************************
diff --git a/src/perl/textui/TextUI.xs b/src/perl/textui/TextUI.xs
index e2f162a0..9f4fd0b0 100644
--- a/src/perl/textui/TextUI.xs
+++ b/src/perl/textui/TextUI.xs
@@ -205,6 +205,28 @@ gui_input_set_pos(pos)
 CODE:
 	gui_entry_set_pos(active_entry, pos);
 
+int
+wcwidth(c)
+	char *c
+CODE:
+	if (term_type == TERM_TYPE_UTF8) {
+		unichar chr = g_utf8_get_char_validated((const char *) c, -1);
+
+		if (chr & 0x80000000) {
+			RETVAL = 1;
+		} else {
+			RETVAL = i_wcwidth(chr);
+		}
+	} else if (term_type != TERM_TYPE_BIG5 ||
+		   c[1] == '\0' ||
+		   !is_big5((unsigned char) c[0], (unsigned char) c[1])) {
+		RETVAL = i_wcwidth((unsigned char) *c);
+	} else {
+		RETVAL = 2;
+	}
+OUTPUT:
+	RETVAL
+
 MODULE = Irssi::TextUI PACKAGE = Irssi::UI::Window
 
 void