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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.
1 parent ee7a677 commit cd00406

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17 files changed

+98
-91
lines changed

17 files changed

+98
-91
lines changed

‎contrib/pgcrypto/internal.c

Lines changed: 3 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -26,7 +26,7 @@
2626
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
2727
* SUCH DAMAGE.
2828
*
29-
* $PostgreSQL: pgsql/contrib/pgcrypto/internal.c,v 1.27 2007/11/15 21:14:31 momjian Exp $
29+
* $PostgreSQL: pgsql/contrib/pgcrypto/internal.c,v 1.28 2008/02/17 02:09:26 tgl Exp $
3030
*/
3131

3232
#include "postgres.h"
@@ -649,7 +649,8 @@ system_reseed(void)
649649
skip = 1;
650650
else if ((t - seed_time) > SYSTEM_RESEED_MAX)
651651
skip = 0;
652-
else if (!check_time || (t - check_time) > SYSTEM_RESEED_CHECK_TIME)
652+
else if (check_time == 0 ||
653+
(t - check_time) > SYSTEM_RESEED_CHECK_TIME)
653654
{
654655
check_time = t;
655656

‎src/backend/access/transam/xlog.c

Lines changed: 13 additions & 13 deletions
Original file line numberDiff line numberDiff line change
@@ -7,7 +7,7 @@
77
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
88
* Portions Copyright (c) 1994, Regents of the University of California
99
*
10-
* $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.292 2008/01/21 11:17:46 petere Exp $
10+
* $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.293 2008/02/17 02:09:27 tgl Exp $
1111
*
1212
*-------------------------------------------------------------------------
1313
*/
@@ -271,7 +271,7 @@ typedef struct XLogCtlWrite
271271
{
272272
XLogwrtResult LogwrtResult; /* current value of LogwrtResult */
273273
int curridx; /* cache index of next block to write */
274-
time_t lastSegSwitchTime; /* time of last xlog segment switch */
274+
pg_time_t lastSegSwitchTime; /* time of last xlog segment switch */
275275
} XLogCtlWrite;
276276

277277
/*
@@ -1553,7 +1553,7 @@ XLogWrite(XLogwrtRqst WriteRqst, bool flexible, bool xlog_switch)
15531553
if (XLogArchivingActive())
15541554
XLogArchiveNotifySeg(openLogId, openLogSeg);
15551555

1556-
Write->lastSegSwitchTime = time(NULL);
1556+
Write->lastSegSwitchTime = (pg_time_t) time(NULL);
15571557

15581558
/*
15591559
* Signal bgwriter to start a checkpoint if we've consumed too
@@ -4217,7 +4217,7 @@ BootStrapXLOG(void)
42174217
checkPoint.nextOid = FirstBootstrapObjectId;
42184218
checkPoint.nextMulti = FirstMultiXactId;
42194219
checkPoint.nextMultiOffset = 0;
4220-
checkPoint.time = time(NULL);
4220+
checkPoint.time = (pg_time_t) time(NULL);
42214221

42224222
ShmemVariableCache->nextXid = checkPoint.nextXid;
42234223
ShmemVariableCache->nextOid = checkPoint.nextOid;
@@ -4972,7 +4972,7 @@ StartupXLOG(void)
49724972
ControlFile->checkPointCopy = checkPoint;
49734973
if (minRecoveryLoc.xlogid != 0 || minRecoveryLoc.xrecoff != 0)
49744974
ControlFile->minRecoveryPoint = minRecoveryLoc;
4975-
ControlFile->time = time(NULL);
4975+
ControlFile->time = (pg_time_t) time(NULL);
49764976
UpdateControlFile();
49774977

49784978
/*
@@ -5277,7 +5277,7 @@ StartupXLOG(void)
52775277
InRecovery = false;
52785278

52795279
ControlFile->state = DB_IN_PRODUCTION;
5280-
ControlFile->time = time(NULL);
5280+
ControlFile->time = (pg_time_t) time(NULL);
52815281
UpdateControlFile();
52825282

52835283
/* start the archive_timeout timer running */
@@ -5496,10 +5496,10 @@ GetInsertRecPtr(void)
54965496
/*
54975497
* Get the time of the last xlog segment switch
54985498
*/
5499-
time_t
5499+
pg_time_t
55005500
GetLastSegSwitchTime(void)
55015501
{
5502-
time_t result;
5502+
pg_time_t result;
55035503

55045504
/* Need WALWriteLock, but shared lock is sufficient */
55055505
LWLockAcquire(WALWriteLock, LW_SHARED);
@@ -5676,7 +5676,7 @@ CreateCheckPoint(int flags)
56765676
if (shutdown)
56775677
{
56785678
ControlFile->state = DB_SHUTDOWNING;
5679-
ControlFile->time = time(NULL);
5679+
ControlFile->time = (pg_time_t) time(NULL);
56805680
UpdateControlFile();
56815681
}
56825682

@@ -5690,7 +5690,7 @@ CreateCheckPoint(int flags)
56905690
/* Begin filling in the checkpoint WAL record */
56915691
MemSet(&checkPoint, 0, sizeof(checkPoint));
56925692
checkPoint.ThisTimeLineID = ThisTimeLineID;
5693-
checkPoint.time = time(NULL);
5693+
checkPoint.time = (pg_time_t) time(NULL);
56945694

56955695
/*
56965696
* We must hold WALInsertLock while examining insert state to determine
@@ -5891,7 +5891,7 @@ CreateCheckPoint(int flags)
58915891
ControlFile->prevCheckPoint = ControlFile->checkPoint;
58925892
ControlFile->checkPoint = ProcLastRecPtr;
58935893
ControlFile->checkPointCopy = checkPoint;
5894-
ControlFile->time = time(NULL);
5894+
ControlFile->time = (pg_time_t) time(NULL);
58955895
UpdateControlFile();
58965896
LWLockRelease(ControlFileLock);
58975897

@@ -5992,7 +5992,7 @@ RecoveryRestartPoint(const CheckPoint *checkPoint)
59925992
* Checking true elapsed time keeps us from doing restartpoints too often
59935993
* while rapidly scanning large amounts of WAL.
59945994
*/
5995-
elapsed_secs = time(NULL) - ControlFile->time;
5995+
elapsed_secs = (pg_time_t) time(NULL) - ControlFile->time;
59965996
if (elapsed_secs < CheckPointTimeout / 2)
59975997
return;
59985998

@@ -6028,7 +6028,7 @@ RecoveryRestartPoint(const CheckPoint *checkPoint)
60286028
ControlFile->prevCheckPoint = ControlFile->checkPoint;
60296029
ControlFile->checkPoint = ReadRecPtr;
60306030
ControlFile->checkPointCopy = *checkPoint;
6031-
ControlFile->time = time(NULL);
6031+
ControlFile->time = (pg_time_t) time(NULL);
60326032
UpdateControlFile();
60336033

60346034
ereport((recoveryLogRestartpoints ? LOG : DEBUG2),

‎src/backend/postmaster/bgwriter.c

Lines changed: 11 additions & 11 deletions
Original file line numberDiff line numberDiff line change
@@ -37,7 +37,7 @@
3737
*
3838
*
3939
* IDENTIFICATION
40-
* $PostgreSQL: pgsql/src/backend/postmaster/bgwriter.c,v 1.48 2008/01/01 19:45:51 momjian Exp $
40+
* $PostgreSQL: pgsql/src/backend/postmaster/bgwriter.c,v 1.49 2008/02/17 02:09:27 tgl Exp $
4141
*
4242
*-------------------------------------------------------------------------
4343
*/
@@ -163,12 +163,12 @@ static bool am_bg_writer = false;
163163
static bool ckpt_active = false;
164164

165165
/* these values are valid when ckpt_active is true: */
166-
static time_t ckpt_start_time;
166+
static pg_time_t ckpt_start_time;
167167
static XLogRecPtr ckpt_start_recptr;
168168
static double ckpt_cached_elapsed;
169169

170-
static time_t last_checkpoint_time;
171-
static time_t last_xlog_switch_time;
170+
static pg_time_t last_checkpoint_time;
171+
static pg_time_t last_xlog_switch_time;
172172

173173
/* Prototypes for private functions */
174174

@@ -250,7 +250,7 @@ BackgroundWriterMain(void)
250250
/*
251251
* Initialize so that first time-driven event happens at the correct time.
252252
*/
253-
last_checkpoint_time = last_xlog_switch_time = time(NULL);
253+
last_checkpoint_time = last_xlog_switch_time = (pg_time_t) time(NULL);
254254

255255
/*
256256
* Create a resource owner to keep track of our resources (currently only
@@ -361,7 +361,7 @@ BackgroundWriterMain(void)
361361
{
362362
bool do_checkpoint = false;
363363
int flags = 0;
364-
time_t now;
364+
pg_time_t now;
365365
int elapsed_secs;
366366

367367
/*
@@ -407,7 +407,7 @@ BackgroundWriterMain(void)
407407
* occurs without an external request, but we set the CAUSE_TIME flag
408408
* bit even if there is also an external request.
409409
*/
410-
now = time(NULL);
410+
now = (pg_time_t) time(NULL);
411411
elapsed_secs = now - last_checkpoint_time;
412412
if (elapsed_secs >= CheckPointTimeout)
413413
{
@@ -504,13 +504,13 @@ BackgroundWriterMain(void)
504504
static void
505505
CheckArchiveTimeout(void)
506506
{
507-
time_t now;
508-
time_t last_time;
507+
pg_time_t now;
508+
pg_time_t last_time;
509509

510510
if (XLogArchiveTimeout <= 0)
511511
return;
512512

513-
now = time(NULL);
513+
now = (pg_time_t) time(NULL);
514514

515515
/* First we do a quick check using possibly-stale local state. */
516516
if ((int) (now - last_xlog_switch_time) < XLogArchiveTimeout)
@@ -730,7 +730,7 @@ IsCheckpointOnSchedule(double progress)
730730
* Check progress against time elapsed and checkpoint_timeout.
731731
*/
732732
gettimeofday(&now, NULL);
733-
elapsed_time = ((double) (now.tv_sec - ckpt_start_time) +
733+
elapsed_time = ((double) ((pg_time_t) now.tv_sec - ckpt_start_time) +
734734
now.tv_usec / 1000000.0) / CheckPointTimeout;
735735

736736
if (progress < elapsed_time)

‎src/backend/postmaster/syslogger.c

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -18,7 +18,7 @@
1818
*
1919
*
2020
* IDENTIFICATION
21-
* $PostgreSQL: pgsql/src/backend/postmaster/syslogger.c,v 1.44 2008/01/25 20:42:10 tgl Exp $
21+
* $PostgreSQL: pgsql/src/backend/postmaster/syslogger.c,v 1.45 2008/02/17 02:09:27 tgl Exp $
2222
*
2323
*-------------------------------------------------------------------------
2424
*/
@@ -331,7 +331,7 @@ SysLoggerMain(int argc, char *argv[])
331331
if (!rotation_requested && Log_RotationAge > 0)
332332
{
333333
/* Do a logfile rotation if it's time */
334-
pg_time_t now = time(NULL);
334+
pg_time_t now = (pg_time_t) time(NULL);
335335

336336
if (now >= next_rotation_time)
337337
rotation_requested = time_based_rotation = true;

‎src/backend/utils/adt/date.c

Lines changed: 6 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/utils/adt/date.c,v 1.138 2008/01/01 19:45:52 momjian Exp $
11+
* $PostgreSQL: pgsql/src/backend/utils/adt/date.c,v 1.139 2008/02/17 02:09:28 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -945,8 +945,10 @@ tm2time(struct pg_tm * tm, fsec_t fsec, TimeADT *result)
945945

946946
/* time2tm()
947947
* Convert time data type to POSIX time structure.
948-
* For dates within the system-supported time_t range, convert to the
949-
* local time zone. If out of this range, leave as GMT. - tgl 97/05/27
948+
*
949+
* For dates within the range of pg_time_t, convert to the local time zone.
950+
* If out of this range, leave as UTC (in practice that could only happen
951+
* if pg_time_t is just 32 bits) - thomas 97/05/27
950952
*/
951953
static int
952954
time2tm(TimeADT time, struct pg_tm * tm, fsec_t *fsec)
@@ -2466,10 +2468,9 @@ timetz_zone(PG_FUNCTION_ARGS)
24662468
if (tzp)
24672469
{
24682470
/* Get the offset-from-GMT that is valid today for the selected zone */
2469-
pg_time_t now;
2471+
pg_time_t now = (pg_time_t) time(NULL);
24702472
struct pg_tm *tm;
24712473

2472-
now = time(NULL);
24732474
tm = pg_localtime(&now, tzp);
24742475
tz = -tm->tm_gmtoff;
24752476
}

‎src/backend/utils/adt/datetime.c

Lines changed: 6 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/utils/adt/datetime.c,v 1.184 2008/01/01 19:45:52 momjian Exp $
11+
* $PostgreSQL: pgsql/src/backend/utils/adt/datetime.c,v 1.185 2008/02/17 02:09:28 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -650,9 +650,11 @@ ParseDateTime(const char *timestr, char *workbuf, size_t buflen,
650650
* "20011225T040506.789-07"
651651
*
652652
* Use the system-provided functions to get the current time zone
653-
* if not specified in the input string.
654-
* If the date is outside the time_t system-supported time range,
655-
* then assume UTC time zone. - thomas 1997-05-27
653+
* if not specified in the input string.
654+
*
655+
* If the date is outside the range of pg_time_t (in practice that could only
656+
* happen if pg_time_t is just 32 bits), then assume UTC time zone - thomas
657+
* 1997-05-27
656658
*/
657659
int
658660
DecodeDateTime(char **field, int *ftype, int nf,

‎src/backend/utils/adt/nabstime.c

Lines changed: 4 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -10,7 +10,7 @@
1010
*
1111
*
1212
* IDENTIFICATION
13-
* $PostgreSQL: pgsql/src/backend/utils/adt/nabstime.c,v 1.152 2008/01/01 19:45:52 momjian Exp $
13+
* $PostgreSQL: pgsql/src/backend/utils/adt/nabstime.c,v 1.153 2008/02/17 02:09:28 tgl Exp $
1414
*
1515
*-------------------------------------------------------------------------
1616
*/
@@ -86,6 +86,8 @@ static void parsetinterval(char *i_string,
8686
* GetCurrentAbsoluteTime()
8787
*
8888
* Get the current system time (relative to Unix epoch).
89+
*
90+
* NB: this will overflow in 2038; it should be gone long before that.
8991
*/
9092
AbsoluteTime
9193
GetCurrentAbsoluteTime(void)
@@ -1029,12 +1031,7 @@ tintervalrel(PG_FUNCTION_ARGS)
10291031
Datum
10301032
timenow(PG_FUNCTION_ARGS)
10311033
{
1032-
time_t sec;
1033-
1034-
if (time(&sec) < 0)
1035-
PG_RETURN_ABSOLUTETIME(INVALID_ABSTIME);
1036-
1037-
PG_RETURN_ABSOLUTETIME((AbsoluteTime) sec);
1034+
PG_RETURN_ABSOLUTETIME(GetCurrentAbsoluteTime());
10381035
}
10391036

10401037
/*

‎src/backend/utils/adt/timestamp.c

Lines changed: 16 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/utils/adt/timestamp.c,v 1.184 2008/01/01 19:45:52 momjian Exp $
11+
* $PostgreSQL: pgsql/src/backend/utils/adt/timestamp.c,v 1.185 2008/02/17 02:09:28 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -1264,9 +1264,14 @@ TimestampDifferenceExceeds(TimestampTz start_time,
12641264
*
12651265
* We do not use time_t internally in Postgres, but this is provided for use
12661266
* by functions that need to interpret, say, a stat(2) result.
1267+
*
1268+
* To avoid having the function's ABI vary depending on the width of time_t,
1269+
* we declare the argument as pg_time_t, which is cast-compatible with
1270+
* time_t but always 64 bits wide (unless the platform has no 64-bit type).
1271+
* This detail should be invisible to callers, at least at source code level.
12671272
*/
12681273
TimestampTz
1269-
time_t_to_timestamptz(time_t tm)
1274+
time_t_to_timestamptz(pg_time_t tm)
12701275
{
12711276
TimestampTz result;
12721277

@@ -1284,17 +1289,22 @@ time_t_to_timestamptz(time_t tm)
12841289
* Convert a TimestampTz to time_t.
12851290
*
12861291
* This too is just marginally useful, but some places need it.
1292+
*
1293+
* To avoid having the function's ABI vary depending on the width of time_t,
1294+
* we declare the result as pg_time_t, which is cast-compatible with
1295+
* time_t but always 64 bits wide (unless the platform has no 64-bit type).
1296+
* This detail should be invisible to callers, at least at source code level.
12871297
*/
1288-
time_t
1298+
pg_time_t
12891299
timestamptz_to_time_t(TimestampTz t)
12901300
{
1291-
time_t result;
1301+
pg_time_t result;
12921302

12931303
#ifdef HAVE_INT64_TIMESTAMP
1294-
result = (time_t) (t / USECS_PER_SEC +
1304+
result = (pg_time_t) (t / USECS_PER_SEC +
12951305
((POSTGRES_EPOCH_JDATE - UNIX_EPOCH_JDATE) * SECS_PER_DAY));
12961306
#else
1297-
result = (time_t) (t +
1307+
result = (pg_time_t) (t +
12981308
((POSTGRES_EPOCH_JDATE - UNIX_EPOCH_JDATE) * SECS_PER_DAY));
12991309
#endif
13001310

‎src/backend/utils/init/globals.c

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/utils/init/globals.c,v 1.104 2008/01/01 19:45:53 momjian Exp $
11+
* $PostgreSQL: pgsql/src/backend/utils/init/globals.c,v 1.105 2008/02/17 02:09:29 tgl Exp $
1212
*
1313
* NOTES
1414
* Globals used all over the place should be declared here and not
@@ -33,7 +33,7 @@ volatile uint32 InterruptHoldoffCount = 0;
3333
volatile uint32 CritSectionCount = 0;
3434

3535
int MyProcPid;
36-
time_t MyStartTime;
36+
pg_time_t MyStartTime;
3737
struct Port *MyProcPort;
3838
long MyCancelKey;
3939

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