Replace time_t with pg_time_t (same values, but always int64) in on-disk

data structures and backend internal APIs.  This solves problems we've seen
recently with inconsistent layout of pg_control between machines that have
32-bit time_t and those that have already migrated to 64-bit time_t.  Also,
we can get out from under the problem that Windows' Unix-API emulation is not
consistent about the width of time_t.

There are a few remaining places where local time_t variables are used to hold
the current or recent result of time(NULL).  I didn't bother changing these
since they do not affect any cross-module APIs and surely all platforms will
have 64-bit time_t before overflow becomes an actual risk.  time_t should
be avoided for anything visible to extension modules, however.

2 files changed, 16 insertions, 8 deletions

diff --git a/src/bin/pg_controldata/pg_controldata.c b/src/bin/pg_controldata/pg_controldata.c
index 682a5cf3807..4cb6ada3129 100644
--- a/src/bin/pg_controldata/pg_controldata.c
+++ b/src/bin/pg_controldata/pg_controldata.c
@@ -6,7 +6,7 @@
  * copyright (c) Oliver Elphick <olly@lfix.co.uk>, 2001;
  * licence: BSD
  *
- * $PostgreSQL: pgsql/src/bin/pg_controldata/pg_controldata.c,v 1.36 2008/01/21 11:17:46 petere Exp $
+ * $PostgreSQL: pgsql/src/bin/pg_controldata/pg_controldata.c,v 1.37 2008/02/17 02:09:29 tgl Exp $
  */
 #include "postgres.h"
 
@@ -69,6 +69,7 @@ main(int argc, char *argv[])
 	char		ControlFilePath[MAXPGPATH];
 	char	   *DataDir;
 	pg_crc32	crc;
+	time_t		time_tmp;
 	char		pgctime_str[128];
 	char		ckpttime_str[128];
 	char		sysident_str[32];
@@ -134,13 +135,20 @@ main(int argc, char *argv[])
 				 "is expecting.  The results below are untrustworthy.\n\n"));
 
 	/*
+	 * This slightly-chintzy coding will work as long as the control file
+	 * timestamps are within the range of time_t; that should be the case
+	 * in all foreseeable circumstances, so we don't bother importing the
+	 * backend's timezone library into pg_controldata.
+	 *
 	 * Use variable for format to suppress overly-anal-retentive gcc warning
 	 * about %c
 	 */
+	time_tmp = (time_t) ControlFile.time;
 	strftime(pgctime_str, sizeof(pgctime_str), strftime_fmt,
-			 localtime(&(ControlFile.time)));
+			 localtime(&time_tmp));
+	time_tmp = (time_t) ControlFile.checkPointCopy.time;
 	strftime(ckpttime_str, sizeof(ckpttime_str), strftime_fmt,
-			 localtime(&(ControlFile.checkPointCopy.time)));
+			 localtime(&time_tmp));
 
 	/*
 	 * Format system_identifier separately to keep platform-dependent format
diff --git a/src/bin/pg_resetxlog/pg_resetxlog.c b/src/bin/pg_resetxlog/pg_resetxlog.c
index 83b6b4b1d7a..86c4463a2ce 100644
--- a/src/bin/pg_resetxlog/pg_resetxlog.c
+++ b/src/bin/pg_resetxlog/pg_resetxlog.c
@@ -23,7 +23,7 @@
  * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/bin/pg_resetxlog/pg_resetxlog.c,v 1.63 2008/01/01 19:45:55 momjian Exp $
+ * $PostgreSQL: pgsql/src/bin/pg_resetxlog/pg_resetxlog.c,v 1.64 2008/02/17 02:09:30 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -471,10 +471,10 @@ GuessControlValues(void)
 	ControlFile.checkPointCopy.nextOid = FirstBootstrapObjectId;
 	ControlFile.checkPointCopy.nextMulti = FirstMultiXactId;
 	ControlFile.checkPointCopy.nextMultiOffset = 0;
-	ControlFile.checkPointCopy.time = time(NULL);
+	ControlFile.checkPointCopy.time = (pg_time_t) time(NULL);
 
 	ControlFile.state = DB_SHUTDOWNED;
-	ControlFile.time = time(NULL);
+	ControlFile.time = (pg_time_t) time(NULL);
 	ControlFile.checkPoint = ControlFile.checkPointCopy.redo;
 
 	ControlFile.maxAlign = MAXIMUM_ALIGNOF;
@@ -603,10 +603,10 @@ RewriteControlFile(void)
 	ControlFile.checkPointCopy.redo.xlogid = newXlogId;
 	ControlFile.checkPointCopy.redo.xrecoff =
 		newXlogSeg * XLogSegSize + SizeOfXLogLongPHD;
-	ControlFile.checkPointCopy.time = time(NULL);
+	ControlFile.checkPointCopy.time = (pg_time_t) time(NULL);
 
 	ControlFile.state = DB_SHUTDOWNED;
-	ControlFile.time = time(NULL);
+	ControlFile.time = (pg_time_t) time(NULL);
 	ControlFile.checkPoint = ControlFile.checkPointCopy.redo;
 	ControlFile.prevCheckPoint.xlogid = 0;
 	ControlFile.prevCheckPoint.xrecoff = 0;