Prevent locale-aware handling of upper, lower, and initcap when the

locale is C.

Backpatch to 8.0.X because some operating systems were throwing errors
for such operations, rather than ignoring the locale when it was C.

src/backend/utils/adt/oracle_compat.c

@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	$PostgreSQL: pgsql/src/backend/utils/adt/oracle_compat.c,v 1.57 2004/12/31 22:01:22 pgsql Exp $
+ *	$PostgreSQL: pgsql/src/backend/utils/adt/oracle_compat.c,v 1.58 2005/03/16 00:02:48 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -166,8 +166,8 @@ Datum
 lower(PG_FUNCTION_ARGS)
 {
 #ifdef USE_WIDE_UPPER_LOWER
-	/* use wide char code only when max encoding length > one */
-	if (pg_database_encoding_max_length() > 1)
+	/* use wide char code only when max encoding length > 1 and ctype != C */
+	if (pg_database_encoding_max_length() > 1 && !lc_ctype_is_c())
 	{
 		text	   *string = PG_GETARG_TEXT_P(0);
 		text	   *result;
@@ -228,8 +228,8 @@ Datum
 upper(PG_FUNCTION_ARGS)
 {
 #ifdef USE_WIDE_UPPER_LOWER
-	/* use wide char code only when max encoding length > one */
-	if (pg_database_encoding_max_length() > 1)
+	/* use wide char code only when max encoding length > 1 and ctype != C */
+	if (pg_database_encoding_max_length() > 1 && !lc_ctype_is_c())
 	{
 		text	   *string = PG_GETARG_TEXT_P(0);
 		text	   *result;
@@ -293,8 +293,8 @@ Datum
 initcap(PG_FUNCTION_ARGS)
 {
 #ifdef USE_WIDE_UPPER_LOWER
-	/* use wide char code only when max encoding length > one */
-	if (pg_database_encoding_max_length() > 1)
+	/* use wide char code only when max encoding length > 1 and ctype != C */
+	if (pg_database_encoding_max_length() > 1 && !lc_ctype_is_c())
 	{
 		text	   *string = PG_GETARG_TEXT_P(0);
 		text	   *result;

src/backend/utils/adt/pg_locale.c

@@ -4,7 +4,7 @@
  *
  * Portions Copyright (c) 2002-2005, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/backend/utils/adt/pg_locale.c,v 1.30 2005/01/01 05:43:07 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/pg_locale.c,v 1.31 2005/03/16 00:02:49 momjian Exp $
  *
  *-----------------------------------------------------------------------
  */
@@ -196,6 +196,33 @@ lc_collate_is_c(void)
 }
 
 
+/*
+ * We'd like to cache whether LC_CTYPE is C (or POSIX), so we can
+ * optimize a few code paths in various places.
+ */
+bool
+lc_ctype_is_c(void)
+{
+	/* Cache result so we only have to compute it once */
+	static int	result = -1;
+	char	   *localeptr;
+
+	if (result >= 0)
+		return (bool) result;
+	localeptr = setlocale(LC_CTYPE, NULL);
+	if (!localeptr)
+		elog(ERROR, "invalid LC_CTYPE setting");
+
+	if (strcmp(localeptr, "C") == 0)
+		result = true;
+	else if (strcmp(localeptr, "POSIX") == 0)
+		result = true;
+	else
+		result = false;
+	return (bool) result;
+}
+
+
 /*
  * Frees the malloced content of a struct lconv.  (But not the struct
  * itself.)

src/include/utils/pg_locale.h

@@ -2,7 +2,7 @@
  *
  * PostgreSQL locale utilities
  *
- * $PostgreSQL: pgsql/src/include/utils/pg_locale.h,v 1.19 2005/01/01 05:43:09 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/utils/pg_locale.h,v 1.20 2005/03/16 00:02:49 momjian Exp $
  *
  * Copyright (c) 2002-2005, PostgreSQL Global Development Group
  *
@@ -32,6 +32,7 @@ extern const char *locale_time_assign(const char *value,
 				   bool doit, GucSource source);
 
 extern bool lc_collate_is_c(void);
+extern bool lc_ctype_is_c(void);
 
 /*
  * Return the POSIX lconv struct (contains number/money formatting