I really hope that I haven't missed anything in this one...

From: t-ishii@sra.co.jp

Attached are patches to enhance the multi-byte support.  (patches are
against 7/18 snapshot)

* determine encoding at initdb/createdb rather than compile time

Now initdb/createdb has an option to specify the encoding. Also, I
modified the syntax of CREATE DATABASE to accept encoding option. See
README.mb for more details.

For this purpose I have added new column "encoding" to pg_database.
Also pg_attribute and pg_class are changed to catch up the
modification to pg_database.  Actually I haved added pg_database_mb.h,
pg_attribute_mb.h and pg_class_mb.h. These are used only when MB is
enabled. The reason having separate files is I couldn't find a way to
use ifdef or whatever in those files. I have to admit it looks
ugly. No way.

* support for PGCLIENTENCODING when issuing COPY command

commands/copy.c modified.

* support for SQL92 syntax "SET NAMES"

See gram.y.

* support for LATIN2-5
* add UNICODE regression test case
* new test suite for MB

New directory test/mb added.

* clean up source files

Basic idea is to have MB's own subdirectory for easier maintenance.
These are include/mb and backend/utils/mb.

src/backend/utils/mb/wstrncmp.c

@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 1989, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from FreeBSD 2.2.1-RELEASE software.
+ *
+ * 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.
+ */
+
+#include <mb/pg_wchar.h>
+
+int
+pg_wchar_strncmp(s1, s2, n)
+	register const pg_wchar *s1, *s2;
+	register size_t n;
+{
+
+	if (n == 0)
+		return (0);
+	do {
+		if (*s1 != *s2++)
+			return (*(const pg_wchar *)s1 -
+				*(const pg_wchar *)(s2 - 1));
+		if (*s1++ == 0)
+			break;
+	} while (--n != 0);
+	return (0);
+}
+
+int
+pg_char_and_wchar_strncmp(s1, s2, n)
+	register const char *s1;
+	register const pg_wchar *s2;
+	register size_t n;
+{
+
+	if (n == 0)
+		return (0);
+	do {
+		if ((pg_wchar )*s1 != *s2++)
+			return (*(const pg_wchar *)s1 -
+				*(const pg_wchar *)(s2 - 1));
+		if (*s1++ == 0)
+			break;
+	} while (--n != 0);
+	return (0);
+}
+
+size_t
+pg_wchar_strlen(str)
+	const pg_wchar *str;
+{
+	register const pg_wchar *s;
+
+	for (s = str; *s; ++s);
+	return(s - str);
+}