I have added the support for BIG5 encoding into libc/libxpg4/mklocale.

the diff is attached below. This is done on the 3.0 source-tree.
I have test this on 2.2-stable before, but I don't have a 3.0 machine
right now.

This patch is mainly to make libc support BIG5 encoding, thus add
zh_TW.BIG5 locale to 3.0.

Submitted by:	Chen Hsiung Chan <frankch@waru.life.nthu.edu.tw>

3 files changed, 127 insertions, 5 deletions

diff --git a/lib/libc/locale/Makefile.inc b/lib/libc/locale/Makefile.inc
index 1b10cc5..54f0287 100644
--- a/lib/libc/locale/Makefile.inc
+++ b/lib/libc/locale/Makefile.inc
@@ -1,13 +1,13 @@
 #	from @(#)Makefile.inc	8.1 (Berkeley) 6/4/93
-#	$Id: Makefile.inc,v 1.11 1997/10/21 08:41:07 bde Exp $
+#	$Id: Makefile.inc,v 1.12 1998/02/20 08:17:23 jb Exp $
 
 # locale sources
 .PATH: ${.CURDIR}/../libc/${MACHINE_ARCH}/locale ${.CURDIR}/../libc/locale
 
-SRCS+=	ansi.c collate.c collcmp.c ctype.c euc.c frune.c isctype.c lconv.c \
-	localeconv.c mbrune.c mskanji.c nomacros.c none.c rune.c runetype.c \
-	setinvalidrune.c setlocale.c setrunelocale.c table.c tolower.c \
-	toupper.c utf2.c
+SRCS+=	ansi.c big5.c collate.c collcmp.c ctype.c euc.c frune.c isctype.c \
+	lconv.c localeconv.c mbrune.c mskanji.c nomacros.c none.c rune.c \
+	runetype.c setinvalidrune.c setlocale.c setrunelocale.c table.c \
+	tolower.c toupper.c utf2.c
 
 .if ${LIB} == "c"
 MAN3+=	ctype.3 isalnum.3 isalpha.3 isascii.3 isblank.3 iscntrl.3 \
diff --git a/lib/libc/locale/big5.c b/lib/libc/locale/big5.c
new file mode 100644
index 0000000..edcaa9e
--- /dev/null
+++ b/lib/libc/locale/big5.c
@@ -0,0 +1,119 @@
+/*-
+ * Copyright (c) 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Paul Borman at Krystal Technologies.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifdef XPG4
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)big5.c	8.1 (Berkeley) 6/4/93";
+#endif /* LIBC_SCCS and not lint */
+
+#include <errno.h>
+#include <rune.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+rune_t	_BIG5_sgetrune __P((const char *, size_t, char const **));
+int	_BIG5_sputrune __P((rune_t, char *, size_t, char **));
+
+int
+_BIG5_init(rl)
+	_RuneLocale *rl;
+{
+	rl->sgetrune = _BIG5_sgetrune;
+	rl->sputrune = _BIG5_sputrune;
+	_CurrentRuneLocale = rl;
+	__mb_cur_max = 2;
+	return (0);
+}
+
+static inline int
+_big5_check(c)
+	u_int c;
+{
+	c &= 0xff;
+	return ((c >= 0xa1 && c <= 0xfe) ? 2 : 1);
+}
+
+rune_t
+_BIG5_sgetrune(string, n, result)
+	const char *string;
+	size_t n;
+	char const **result;
+{
+	rune_t rune = 0;
+	int len;
+
+	if (n < 1 || (len = _big5_check(*string)) > n) {
+		if (result)
+			*result = string;
+		return (_INVALID_RUNE);
+	}
+	while (len-- >= 0)
+		rune = (rune << 8) | ((u_int)(*string++) & 0xff);
+	if (result)
+		*result = string + len;
+	return rune;
+}
+
+int
+_BIG5_sputrune(c, string, n, result)
+	rune_t c;
+	char *string, **result;
+	size_t n;
+{
+	if (c & 0x8000) {
+		if (n >= 2) {
+			string[0] = (c >> 8) & 0xff;
+			string[1] = c & 0xff;
+			if (result)
+				*result = string + 2;
+			return (2);
+		}
+	}
+	else {
+		if (n >= 1) {
+			*string = c & 0xff;
+			if (result)
+				*result = string + 1;
+			return (1);
+		}
+	}
+	if (result)
+		*result = string;
+	return (0);
+	
+}
+#endif /* XPG4 */
diff --git a/lib/libc/locale/setrunelocale.c b/lib/libc/locale/setrunelocale.c
index c65628e..8cfddab 100644
--- a/lib/libc/locale/setrunelocale.c
+++ b/lib/libc/locale/setrunelocale.c
@@ -47,6 +47,7 @@ extern int		_none_init __P((_RuneLocale *));
 #ifdef XPG4
 extern int		_UTF2_init __P((_RuneLocale *));
 extern int		_EUC_init __P((_RuneLocale *));
+extern int		_BIG5_init __P((_RuneLocale *));
 extern int		_MSKanji_init __P((_RuneLocale *));
 extern int              _xpg4_setrunelocale __P((char *));
 #endif
@@ -128,6 +129,8 @@ _xpg4_setrunelocale(encoding)
 #ifdef XPG4
 	else if (!strcmp(rl->encoding, "EUC"))
 		return(_EUC_init(rl));
+	else if (!strcmp(rl->encoding, "BIG5"))
+		return(_BIG5_init(rl));
 	else if (!strcmp(rl->encoding, "MSKanji"))
 		return(_MSKanji_init(rl));
 #endif