From 494f30c95370cae30984a5f6ec6c200065c64919 Mon Sep 17 00:00:00 2001
From: Bruce Momjian <bruce@momjian.us>
Date: Wed, 16 Mar 2005 00:02:49 +0000
Subject: [PATCH] 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 | 14 ++++++-------
 src/backend/utils/adt/pg_locale.c     | 29 ++++++++++++++++++++++++++-
 src/include/utils/pg_locale.h         |  3 ++-
 3 files changed, 37 insertions(+), 9 deletions(-)

diff --git a/src/backend/utils/adt/oracle_compat.c b/src/backend/utils/adt/oracle_compat.c
index 870ed42d072..0d4828d79c2 100644
--- a/src/backend/utils/adt/oracle_compat.c
+++ b/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;
diff --git a/src/backend/utils/adt/pg_locale.c b/src/backend/utils/adt/pg_locale.c
index 5b8d8e88102..7c9c774d91b 100644
--- a/src/backend/utils/adt/pg_locale.c
+++ b/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.)
diff --git a/src/include/utils/pg_locale.h b/src/include/utils/pg_locale.h
index 6be1df3ab14..ef138d1bcbf 100644
--- a/src/include/utils/pg_locale.h
+++ b/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