Make initdb behave sanely when the selected locale has codeset "US-ASCII".

Per discussion, this should result in defaulting to SQL_ASCII encoding.
The original coding could not support that because it conflated selection
of SQL_ASCII encoding with not being able to determine the encoding.
Adjust pg_get_encoding_from_locale()'s API to distinguish these cases,
and fix callers appropriately.  Only initdb actually changes behavior,
since the other callers were perfectly content to consider these cases
equivalent.

Per bug #5178 from Boh Yap.  Not going to bother back-patching, since
no one has complained before and there's an easy workaround (namely,
specify the encoding you want).

1 files changed, 9 insertions, 2 deletions

diff --git a/src/backend/utils/mb/mbutils.c b/src/backend/utils/mb/mbutils.c
index 5aaaae502f8..c8a43dced6f 100644
--- a/src/backend/utils/mb/mbutils.c
+++ b/src/backend/utils/mb/mbutils.c
@@ -4,7 +4,7 @@
  *
  * Tatsuo Ishii
  *
- * $PostgreSQL: pgsql/src/backend/utils/mb/mbutils.c,v 1.91 2009/10/17 05:14:52 mha Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/mb/mbutils.c,v 1.92 2009/11/12 02:46:16 tgl Exp $
  */
 #include "postgres.h"
 
@@ -984,7 +984,14 @@ int
 GetPlatformEncoding(void)
 {
 	if (PlatformEncoding == NULL)
-		PlatformEncoding = &pg_enc2name_tbl[pg_get_encoding_from_locale("")];
+	{
+		/* try to determine encoding of server's environment locale */
+		int		encoding = pg_get_encoding_from_locale("");
+
+		if (encoding < 0)
+			encoding = PG_SQL_ASCII;
+		PlatformEncoding = &pg_enc2name_tbl[encoding];
+	}
 	return PlatformEncoding->encoding;
 }