Don't use BLCKSZ for the physical length of the pg_control file, but

instead a dedicated symbol.  This probably makes no functional difference
for likely values of BLCKSZ, but it makes the intent clearer.
Simon Riggs, minor editorialization by Tom Lane.

1 files changed, 10 insertions, 1 deletions

diff --git a/src/include/catalog/pg_control.h b/src/include/catalog/pg_control.h
index ba54fdc8e6f..02c51dd9f35 100644
--- a/src/include/catalog/pg_control.h
+++ b/src/include/catalog/pg_control.h
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/catalog/pg_control.h,v 1.28 2006/04/03 23:35:05 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_control.h,v 1.29 2006/04/04 22:39:59 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -147,4 +147,13 @@ typedef struct ControlFileData
 	pg_crc32	crc;
 } ControlFileData;
 
+/*
+ * Physical size of the pg_control file.  Note that this is considerably
+ * bigger than the actually used size (ie, sizeof(ControlFileData)).
+ * The idea is to keep the physical size constant independent of format
+ * changes, so that ReadControlFile will deliver a suitable wrong-version
+ * message instead of a read error if it's looking at an incompatible file.
+ */
+#define PG_CONTROL_SIZE		8192
+
 #endif   /* PG_CONTROL_H */