--- ansi.c.orig	Tue Jun 17 08:00:47 2003
+++ ansi.c	Wed Jun 18 00:55:21 2003
@@ -701,7 +701,7 @@
 	      curr->w_rend.font = 0;
 	    }
 #  ifdef DW_CHARS
-	  if (curr->w_encoding == UTF8 && c >= 0x1100 && utf8_isdouble(c))
+	  if (curr->w_encoding == UTF8 && utf8_isdouble(c))
 	    curr->w_mbcs = 0xff;
 #  endif
 	  if (curr->w_encoding == UTF8 && c >= 0x0300 && utf8_iscomb(c))
--- comm.c.orig	Mon Sep  8 22:25:08 2003
+++ comm.c	Fri May  6 19:06:12 2005
@@ -112,6 +112,9 @@
 #endif
   { "charset",          NEED_FORE|ARGS_1 },
   { "chdir",		ARGS_01 },
+#ifdef DW_CHARS
+  { "cjkwidth",		ARGS_01 },
+#endif
   { "clear",		NEED_FORE|ARGS_0 },
   { "colon",		NEED_LAYER|ARGS_01 },
   { "command",		NEED_DISPLAY|ARGS_02 },
--- encoding.c.orig	Mon Sep  8 22:25:23 2003
+++ encoding.c	Fri May  6 20:05:24 2005
@@ -35,6 +35,10 @@
 
 extern char *screenencodings;
 
+#ifdef DW_CHARS
+extern int cjkwidth;
+#endif
+
 static int  encmatch __P((char *, char *));
 # ifdef UTF8
 static int   recode_char __P((int, int, int));
@@ -845,22 +849,107 @@
 }
 
 #ifdef DW_CHARS
+struct interval {
+  int first;
+  int last;
+};
+
+/* auxiliary function for binary search in interval table */
+static int bisearch(int ucs, const struct interval *table, int max) {
+  int min = 0;
+  int mid;
+
+  if (ucs < table[0].first || ucs > table[max].last)
+    return 0;
+  while (max >= min) {
+    mid = (min + max) / 2;
+    if (ucs > table[mid].last)
+      min = mid + 1;
+    else if (ucs < table[mid].first)
+      max = mid - 1;
+    else
+      return 1;
+  }
+
+  return 0;
+}
+
 int
 utf8_isdouble(c)
 int c;
 {
-  return
-    (c >= 0x1100 &&
-     (c <= 0x115f ||                    /* Hangul Jamo init. consonants */
-      (c >= 0x2e80 && c <= 0xa4cf && (c & ~0x0011) != 0x300a &&
-       c != 0x303f) ||                  /* CJK ... Yi */
-      (c >= 0xac00 && c <= 0xd7a3) || /* Hangul Syllables */
-      (c >= 0xdf00 && c <= 0xdfff) || /* dw combining sequence */
-      (c >= 0xf900 && c <= 0xfaff) || /* CJK Compatibility Ideographs */
-      (c >= 0xfe30 && c <= 0xfe6f) || /* CJK Compatibility Forms */
-      (c >= 0xff00 && c <= 0xff5f) || /* Fullwidth Forms */
-      (c >= 0xffe0 && c <= 0xffe6) ||
-      (c >= 0x20000 && c <= 0x2ffff)));
+  /* sorted list of non-overlapping intervals of East Asian Ambiguous
+   * characters, generated by "uniset +WIDTH-A -cat=Me -cat=Mn -cat=Cf c" */
+  static const struct interval ambiguous[] = {
+    { 0x00A1, 0x00A1 }, { 0x00A4, 0x00A4 }, { 0x00A7, 0x00A8 },
+    { 0x00AA, 0x00AA }, { 0x00AE, 0x00AE }, { 0x00B0, 0x00B4 },
+    { 0x00B6, 0x00BA }, { 0x00BC, 0x00BF }, { 0x00C6, 0x00C6 },
+    { 0x00D0, 0x00D0 }, { 0x00D7, 0x00D8 }, { 0x00DE, 0x00E1 },
+    { 0x00E6, 0x00E6 }, { 0x00E8, 0x00EA }, { 0x00EC, 0x00ED },
+    { 0x00F0, 0x00F0 }, { 0x00F2, 0x00F3 }, { 0x00F7, 0x00FA },
+    { 0x00FC, 0x00FC }, { 0x00FE, 0x00FE }, { 0x0101, 0x0101 },
+    { 0x0111, 0x0111 }, { 0x0113, 0x0113 }, { 0x011B, 0x011B },
+    { 0x0126, 0x0127 }, { 0x012B, 0x012B }, { 0x0131, 0x0133 },
+    { 0x0138, 0x0138 }, { 0x013F, 0x0142 }, { 0x0144, 0x0144 },
+    { 0x0148, 0x014B }, { 0x014D, 0x014D }, { 0x0152, 0x0153 },
+    { 0x0166, 0x0167 }, { 0x016B, 0x016B }, { 0x01CE, 0x01CE },
+    { 0x01D0, 0x01D0 }, { 0x01D2, 0x01D2 }, { 0x01D4, 0x01D4 },
+    { 0x01D6, 0x01D6 }, { 0x01D8, 0x01D8 }, { 0x01DA, 0x01DA },
+    { 0x01DC, 0x01DC }, { 0x0251, 0x0251 }, { 0x0261, 0x0261 },
+    { 0x02C4, 0x02C4 }, { 0x02C7, 0x02C7 }, { 0x02C9, 0x02CB },
+    { 0x02CD, 0x02CD }, { 0x02D0, 0x02D0 }, { 0x02D8, 0x02DB },
+    { 0x02DD, 0x02DD }, { 0x02DF, 0x02DF }, { 0x0391, 0x03A1 },
+    { 0x03A3, 0x03A9 }, { 0x03B1, 0x03C1 }, { 0x03C3, 0x03C9 },
+    { 0x0401, 0x0401 }, { 0x0410, 0x044F }, { 0x0451, 0x0451 },
+    { 0x2010, 0x2010 }, { 0x2013, 0x2016 }, { 0x2018, 0x2019 },
+    { 0x201C, 0x201D }, { 0x2020, 0x2022 }, { 0x2024, 0x2027 },
+    { 0x2030, 0x2030 }, { 0x2032, 0x2033 }, { 0x2035, 0x2035 },
+    { 0x203B, 0x203B }, { 0x203E, 0x203E }, { 0x2074, 0x2074 },
+    { 0x207F, 0x207F }, { 0x2081, 0x2084 }, { 0x20AC, 0x20AC },
+    { 0x2103, 0x2103 }, { 0x2105, 0x2105 }, { 0x2109, 0x2109 },
+    { 0x2113, 0x2113 }, { 0x2116, 0x2116 }, { 0x2121, 0x2122 },
+    { 0x2126, 0x2126 }, { 0x212B, 0x212B }, { 0x2153, 0x2154 },
+    { 0x215B, 0x215E }, { 0x2160, 0x216B }, { 0x2170, 0x2179 },
+    { 0x2190, 0x2199 }, { 0x21B8, 0x21B9 }, { 0x21D2, 0x21D2 },
+    { 0x21D4, 0x21D4 }, { 0x21E7, 0x21E7 }, { 0x2200, 0x2200 },
+    { 0x2202, 0x2203 }, { 0x2207, 0x2208 }, { 0x220B, 0x220B },
+    { 0x220F, 0x220F }, { 0x2211, 0x2211 }, { 0x2215, 0x2215 },
+    { 0x221A, 0x221A }, { 0x221D, 0x2220 }, { 0x2223, 0x2223 },
+    { 0x2225, 0x2225 }, { 0x2227, 0x222C }, { 0x222E, 0x222E },
+    { 0x2234, 0x2237 }, { 0x223C, 0x223D }, { 0x2248, 0x2248 },
+    { 0x224C, 0x224C }, { 0x2252, 0x2252 }, { 0x2260, 0x2261 },
+    { 0x2264, 0x2267 }, { 0x226A, 0x226B }, { 0x226E, 0x226F },
+    { 0x2282, 0x2283 }, { 0x2286, 0x2287 }, { 0x2295, 0x2295 },
+    { 0x2299, 0x2299 }, { 0x22A5, 0x22A5 }, { 0x22BF, 0x22BF },
+    { 0x2312, 0x2312 }, { 0x2460, 0x24E9 }, { 0x24EB, 0x254B },
+    { 0x2550, 0x2573 }, { 0x2580, 0x258F }, { 0x2592, 0x2595 },
+    { 0x25A0, 0x25A1 }, { 0x25A3, 0x25A9 }, { 0x25B2, 0x25B3 },
+    { 0x25B6, 0x25B7 }, { 0x25BC, 0x25BD }, { 0x25C0, 0x25C1 },
+    { 0x25C6, 0x25C8 }, { 0x25CB, 0x25CB }, { 0x25CE, 0x25D1 },
+    { 0x25E2, 0x25E5 }, { 0x25EF, 0x25EF }, { 0x2605, 0x2606 },
+    { 0x2609, 0x2609 }, { 0x260E, 0x260F }, { 0x2614, 0x2615 },
+    { 0x261C, 0x261C }, { 0x261E, 0x261E }, { 0x2640, 0x2640 },
+    { 0x2642, 0x2642 }, { 0x2660, 0x2661 }, { 0x2663, 0x2665 },
+    { 0x2667, 0x266A }, { 0x266C, 0x266D }, { 0x266F, 0x266F },
+    { 0x273D, 0x273D }, { 0x2776, 0x277F }, { 0xE000, 0xF8FF },
+    { 0xFFFD, 0xFFFD }, { 0xF0000, 0xFFFFD }, { 0x100000, 0x10FFFD }
+  };
+
+  return ((c >= 0x1100 &&
+           (c <= 0x115f ||                    /* Hangul Jamo init. consonants */
+            c == 0x2329 || c == 0x232a ||
+            (c >= 0x2e80 && c <= 0xa4cf &&
+             c != 0x303f) ||                  /* CJK ... Yi */
+            (c >= 0xac00 && c <= 0xd7a3) || /* Hangul Syllables */
+            (c >= 0xf900 && c <= 0xfaff) || /* CJK Compatibility Ideographs */
+            (c >= 0xfe30 && c <= 0xfe6f) || /* CJK Compatibility Forms */
+            (c >= 0xff00 && c <= 0xff60) || /* Fullwidth Forms */
+            (c >= 0xffe0 && c <= 0xffe6) ||
+            (c >= 0x20000 && c <= 0x2fffd) ||
+            (c >= 0x30000 && c <= 0x3fffd))) ||
+          (cjkwidth &&
+           bisearch(c, ambiguous,
+	            sizeof(ambiguous) / sizeof(struct interval) - 1)));
 }
 #endif
 
--- process.c.orig	Thu Sep 18 20:53:54 2003
+++ process.c	Fri May  6 19:43:53 2005
@@ -103,6 +103,9 @@
 #ifdef UTF8
 extern char *screenencodings;
 #endif
+#ifdef DW_CHARS
+extern int cjkwidth;
+#endif
 
 static int  CheckArgNum __P((int, char **));
 static void ClearAction __P((struct action *));
@@ -3821,6 +3824,15 @@
 	    Msg(0, "idle off");
 	}
       break;
+#ifdef DW_CHARS
+    case RC_CJKWIDTH:
+      if(ParseSwitch(act, &cjkwidth) == 0)
+      {
+        if(msgok)
+          Msg(0, "Treat ambiguous width characters as %s width", cjkwidth ? "full" : "half");
+      }
+      break;
+#endif
     default:
 #ifdef HAVE_BRAILLE
       /* key == -2: input from braille keybord, msgok always 0 */
--- screen.c.orig	Mon Sep  8 22:26:41 2003
+++ screen.c	Sat May  7 05:16:38 2005
@@ -221,6 +221,10 @@
 char *screenencodings;
 #endif
 
+#ifdef DW_CHARS
+int cjkwidth;
+#endif
+
 #ifdef NETHACK
 int nethackflag = 0;
 #endif
@@ -468,6 +472,9 @@
   InitBuiltinTabs();
   screenencodings = SaveStr(SCREENENCODINGS);
 #endif
+#ifdef DW_CHARS
+  cjkwidth = 0;
+#endif
   nwin = nwin_undef;
   nwin_options = nwin_undef;
   strcpy(screenterm, "screen");
@@ -762,6 +769,19 @@
       debug1("environment says encoding=%d\n", nwin_options.encoding);
 #endif
     }
+# ifdef DW_CHARS
+  {
+    char *s;
+    if((s = getenv("LC_ALL")) || (s = getenv("LC_CTYPE")) ||
+       (s = getenv("LANG")))
+    {
+      if(!strncmp(s, "zh_", 3) || !strncmp(s, "ja_", 3) || !strncmp(s, "ko_", 3))
+      {
+        cjkwidth = 1;
+      }
+    }
+  }
+#endif
 #endif
   if (SockMatch && strlen(SockMatch) >= MAXSTR)
     Panic(0, "Ridiculously long socketname - try again.");