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Move user functions related to WAL into xlogfuncs.c

This commit is contained in:
Simon Riggs 2011-11-04 09:37:17 +00:00
parent e145891c98
commit a030bfa6e4
4 changed files with 499 additions and 446 deletions
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3
src/backend/access/transam/Makefile
View File

@ -12,7 +12,8 @@ subdir = src/backend/access/transam
top_builddir = ../../../..
include $(top_builddir)/src/Makefile.global
OBJS = clog.o transam.o varsup.o xact.o xlog.o xlogutils.o rmgr.o slru.o subtrans.o multixact.o twophase.o twophase_rmgr.o
OBJS = clog.o transam.o varsup.o xact.o rmgr.o slru.o subtrans.o multixact.o \
twophase.o twophase_rmgr.o xlog.o xlogfuncs.o xlogutils.o
include $(top_srcdir)/src/backend/common.mk

470
src/backend/access/transam/xlog.c
View File

@ -35,8 +35,6 @@
#include "catalog/catversion.h"
#include "catalog/pg_control.h"
#include "catalog/pg_database.h"
#include "catalog/pg_type.h"
#include "funcapi.h"
#include "libpq/pqsignal.h"
#include "miscadmin.h"
#include "pgstat.h"
@ -596,10 +594,7 @@ static void exitArchiveRecovery(TimeLineID endTLI,
uint32 endLogId, uint32 endLogSeg);
static bool recoveryStopsHere(XLogRecord *record, bool *includeThis);
static void recoveryPausesHere(void);
static bool RecoveryIsPaused(void);
static void SetRecoveryPause(bool recoveryPause);
static void SetLatestXTime(TimestampTz xtime);
static TimestampTz GetLatestXTime(void);
static void CheckRequiredParameterValues(void);
static void XLogReportParameters(void);
static void LocalSetXLogInsertAllowed(void);
@ -5762,7 +5757,7 @@ recoveryPausesHere(void)
}
}
static bool
bool
RecoveryIsPaused(void)
{
/* use volatile pointer to prevent code rearrangement */
@ -5776,7 +5771,7 @@ RecoveryIsPaused(void)
return recoveryPause;
}
static void
void
SetRecoveryPause(bool recoveryPause)
{
/* use volatile pointer to prevent code rearrangement */
@ -5787,70 +5782,6 @@ SetRecoveryPause(bool recoveryPause)
SpinLockRelease(&xlogctl->info_lck);
}
/*
* pg_xlog_replay_pause - pause recovery now
*/
Datum
pg_xlog_replay_pause(PG_FUNCTION_ARGS)
{
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to control recovery"))));
if (!RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is not in progress"),
errhint("Recovery control functions can only be executed during recovery.")));
SetRecoveryPause(true);
PG_RETURN_VOID();
}
/*
* pg_xlog_replay_resume - resume recovery now
*/
Datum
pg_xlog_replay_resume(PG_FUNCTION_ARGS)
{
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to control recovery"))));
if (!RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is not in progress"),
errhint("Recovery control functions can only be executed during recovery.")));
SetRecoveryPause(false);
PG_RETURN_VOID();
}
/*
* pg_is_xlog_replay_paused
*/
Datum
pg_is_xlog_replay_paused(PG_FUNCTION_ARGS)
{
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to control recovery"))));
if (!RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is not in progress"),
errhint("Recovery control functions can only be executed during recovery.")));
PG_RETURN_BOOL(RecoveryIsPaused());
}
/*
* Save timestamp of latest processed commit/abort record.
*
@ -5872,7 +5803,7 @@ SetLatestXTime(TimestampTz xtime)
/*
* Fetch timestamp of latest processed commit/abort record.
*/
static TimestampTz
TimestampTz
GetLatestXTime(void)
{
/* use volatile pointer to prevent code rearrangement */
@ -5886,33 +5817,6 @@ GetLatestXTime(void)
return xtime;
}
/*
* Returns timestamp of latest processed commit/abort record.
*
* When the server has been started normally without recovery the function
* returns NULL.
*/
Datum
pg_last_xact_replay_timestamp(PG_FUNCTION_ARGS)
{
TimestampTz xtime;
xtime = GetLatestXTime();
if (xtime == 0)
PG_RETURN_NULL();
PG_RETURN_TIMESTAMPTZ(xtime);
}
/*
* Returns bool with current recovery mode, a global state.
*/
Datum
pg_is_in_recovery(PG_FUNCTION_ARGS)
{
PG_RETURN_BOOL(RecoveryInProgress());
}
/*
* Returns time of receipt of current chunk of XLOG data, as well as
* whether it was received from streaming replication or from archives.
@ -8835,34 +8739,6 @@ issue_xlog_fsync(int fd, uint32 log, uint32 seg)
}
}
/*
* pg_start_backup: set up for taking an on-line backup dump
*
* Essentially what this does is to create a backup label file in $PGDATA,
* where it will be archived as part of the backup dump. The label file
* contains the user-supplied label string (typically this would be used
* to tell where the backup dump will be stored) and the starting time and
* starting WAL location for the dump.
*/
Datum
pg_start_backup(PG_FUNCTION_ARGS)
{
text *backupid = PG_GETARG_TEXT_P(0);
bool fast = PG_GETARG_BOOL(1);
char *backupidstr;
XLogRecPtr startpoint;
char startxlogstr[MAXFNAMELEN];
backupidstr = text_to_cstring(backupid);
startpoint = do_pg_start_backup(backupidstr, fast, NULL);
snprintf(startxlogstr, sizeof(startxlogstr), "%X/%X",
startpoint.xlogid, startpoint.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(startxlogstr));
}
/*
* do_pg_start_backup is the workhorse of the user-visible pg_start_backup()
* function. It creates the necessary starting checkpoint and constructs the
@ -9122,32 +8998,6 @@ pg_start_backup_callback(int code, Datum arg)
LWLockRelease(WALInsertLock);
}
/*
* pg_stop_backup: finish taking an on-line backup dump
*
* We write an end-of-backup WAL record, and remove the backup label file
* created by pg_start_backup, creating a backup history file in pg_xlog
* instead (whence it will immediately be archived). The backup history file
* contains the same info found in the label file, plus the backup-end time
* and WAL location. Before 9.0, the backup-end time was read from the backup
* history file at the beginning of archive recovery, but we now use the WAL
* record for that and the file is for informational and debug purposes only.
*
* Note: different from CancelBackup which just cancels online backup mode.
*/
Datum
pg_stop_backup(PG_FUNCTION_ARGS)
{
XLogRecPtr stoppoint;
char stopxlogstr[MAXFNAMELEN];
stoppoint = do_pg_stop_backup(NULL, true);
snprintf(stopxlogstr, sizeof(stopxlogstr), "%X/%X",
stoppoint.xlogid, stoppoint.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(stopxlogstr));
}
/*
* do_pg_stop_backup is the workhorse of the user-visible pg_stop_backup()
* function.
@ -9433,166 +9283,6 @@ do_pg_abort_backup(void)
LWLockRelease(WALInsertLock);
}
/*
* pg_switch_xlog: switch to next xlog file
*/
Datum
pg_switch_xlog(PG_FUNCTION_ARGS)
{
XLogRecPtr switchpoint;
char location[MAXFNAMELEN];
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to switch transaction log files"))));
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is in progress"),
errhint("WAL control functions cannot be executed during recovery.")));
switchpoint = RequestXLogSwitch();
/*
* As a convenience, return the WAL location of the switch record
*/
snprintf(location, sizeof(location), "%X/%X",
switchpoint.xlogid, switchpoint.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
}
/*
* pg_create_restore_point: a named point for restore
*/
Datum
pg_create_restore_point(PG_FUNCTION_ARGS)
{
text *restore_name = PG_GETARG_TEXT_P(0);
char *restore_name_str;
XLogRecPtr restorepoint;
char location[MAXFNAMELEN];
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to create a restore point"))));
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
(errmsg("recovery is in progress"),
errhint("WAL control functions cannot be executed during recovery."))));
if (!XLogIsNeeded())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("WAL level not sufficient for creating a restore point"),
errhint("wal_level must be set to \"archive\" or \"hot_standby\" at server start.")));
restore_name_str = text_to_cstring(restore_name);
if (strlen(restore_name_str) >= MAXFNAMELEN)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("value too long for restore point (maximum %d characters)", MAXFNAMELEN - 1)));
restorepoint = XLogRestorePoint(restore_name_str);
/*
* As a convenience, return the WAL location of the restore point record
*/
snprintf(location, sizeof(location), "%X/%X",
restorepoint.xlogid, restorepoint.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
}
/*
* Report the current WAL write location (same format as pg_start_backup etc)
*
* This is useful for determining how much of WAL is visible to an external
* archiving process. Note that the data before this point is written out
* to the kernel, but is not necessarily synced to disk.
*/
Datum
pg_current_xlog_location(PG_FUNCTION_ARGS)
{
char location[MAXFNAMELEN];
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is in progress"),
errhint("WAL control functions cannot be executed during recovery.")));
/* Make sure we have an up-to-date local LogwrtResult */
{
/* use volatile pointer to prevent code rearrangement */
volatile XLogCtlData *xlogctl = XLogCtl;
SpinLockAcquire(&xlogctl->info_lck);
LogwrtResult = xlogctl->LogwrtResult;
SpinLockRelease(&xlogctl->info_lck);
}
snprintf(location, sizeof(location), "%X/%X",
LogwrtResult.Write.xlogid, LogwrtResult.Write.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
}
/*
* Report the current WAL insert location (same format as pg_start_backup etc)
*
* This function is mostly for debugging purposes.
*/
Datum
pg_current_xlog_insert_location(PG_FUNCTION_ARGS)
{
XLogCtlInsert *Insert = &XLogCtl->Insert;
XLogRecPtr current_recptr;
char location[MAXFNAMELEN];
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is in progress"),
errhint("WAL control functions cannot be executed during recovery.")));
/*
* Get the current end-of-WAL position ... shared lock is sufficient
*/
LWLockAcquire(WALInsertLock, LW_SHARED);
INSERT_RECPTR(current_recptr, Insert, Insert->curridx);
LWLockRelease(WALInsertLock);
snprintf(location, sizeof(location), "%X/%X",
current_recptr.xlogid, current_recptr.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
}
/*
* Report the last WAL receive location (same format as pg_start_backup etc)
*
* This is useful for determining how much of WAL is guaranteed to be received
* and synced to disk by walreceiver.
*/
Datum
pg_last_xlog_receive_location(PG_FUNCTION_ARGS)
{
XLogRecPtr recptr;
char location[MAXFNAMELEN];
recptr = GetWalRcvWriteRecPtr(NULL);
if (recptr.xlogid == 0 && recptr.xrecoff == 0)
PG_RETURN_NULL();
snprintf(location, sizeof(location), "%X/%X",
recptr.xlogid, recptr.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
}
/*
* Get latest redo apply position.
*
@ -9639,149 +9329,39 @@ GetStandbyFlushRecPtr(void)
}
/*
* Report the last WAL replay location (same format as pg_start_backup etc)
*
* This is useful for determining how much of WAL is visible to read-only
* connections during recovery.
* Get latest WAL insert pointer
*/
Datum
pg_last_xlog_replay_location(PG_FUNCTION_ARGS)
XLogRecPtr
GetXLogInsertRecPtr(bool needlock)
{
XLogRecPtr recptr;
char location[MAXFNAMELEN];
XLogCtlInsert *Insert = &XLogCtl->Insert;
XLogRecPtr current_recptr;
recptr = GetXLogReplayRecPtr(NULL);
if (needlock)
LWLockAcquire(WALInsertLock, LW_SHARED);
INSERT_RECPTR(current_recptr, Insert, Insert->curridx);
if (needlock)
LWLockRelease(WALInsertLock);
if (recptr.xlogid == 0 && recptr.xrecoff == 0)
PG_RETURN_NULL();
snprintf(location, sizeof(location), "%X/%X",
recptr.xlogid, recptr.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
return current_recptr;
}
/*
* Compute an xlog file name and decimal byte offset given a WAL location,
* such as is returned by pg_stop_backup() or pg_xlog_switch().
*
* Note that a location exactly at a segment boundary is taken to be in
* the previous segment. This is usually the right thing, since the
* expected usage is to determine which xlog file(s) are ready to archive.
* Get latest WAL write pointer
*/
Datum
pg_xlogfile_name_offset(PG_FUNCTION_ARGS)
XLogRecPtr
GetXLogWriteRecPtr(void)
{
text *location = PG_GETARG_TEXT_P(0);
char *locationstr;
unsigned int uxlogid;
unsigned int uxrecoff;
uint32 xlogid;
uint32 xlogseg;
uint32 xrecoff;
XLogRecPtr locationpoint;
char xlogfilename[MAXFNAMELEN];
Datum values[2];
bool isnull[2];
TupleDesc resultTupleDesc;
HeapTuple resultHeapTuple;
Datum result;
{
/* use volatile pointer to prevent code rearrangement */
volatile XLogCtlData *xlogctl = XLogCtl;
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is in progress"),
errhint("pg_xlogfile_name_offset() cannot be executed during recovery.")));
SpinLockAcquire(&xlogctl->info_lck);
LogwrtResult = xlogctl->LogwrtResult;
SpinLockRelease(&xlogctl->info_lck);
}
/*
* Read input and parse
*/
locationstr = text_to_cstring(location);
if (sscanf(locationstr, "%X/%X", &uxlogid, &uxrecoff) != 2)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not parse transaction log location \"%s\"",
locationstr)));
locationpoint.xlogid = uxlogid;
locationpoint.xrecoff = uxrecoff;
/*
* Construct a tuple descriptor for the result row. This must match this
* function's pg_proc entry!
*/
resultTupleDesc = CreateTemplateTupleDesc(2, false);
TupleDescInitEntry(resultTupleDesc, (AttrNumber) 1, "file_name",
TEXTOID, -1, 0);
TupleDescInitEntry(resultTupleDesc, (AttrNumber) 2, "file_offset",
INT4OID, -1, 0);
resultTupleDesc = BlessTupleDesc(resultTupleDesc);
/*
* xlogfilename
*/
XLByteToPrevSeg(locationpoint, xlogid, xlogseg);
XLogFileName(xlogfilename, ThisTimeLineID, xlogid, xlogseg);
values[0] = CStringGetTextDatum(xlogfilename);
isnull[0] = false;
/*
* offset
*/
xrecoff = locationpoint.xrecoff - xlogseg * XLogSegSize;
values[1] = UInt32GetDatum(xrecoff);
isnull[1] = false;
/*
* Tuple jam: Having first prepared your Datums, then squash together
*/
resultHeapTuple = heap_form_tuple(resultTupleDesc, values, isnull);
result = HeapTupleGetDatum(resultHeapTuple);
PG_RETURN_DATUM(result);
}
/*
* Compute an xlog file name given a WAL location,
* such as is returned by pg_stop_backup() or pg_xlog_switch().
*/
Datum
pg_xlogfile_name(PG_FUNCTION_ARGS)
{
text *location = PG_GETARG_TEXT_P(0);
char *locationstr;
unsigned int uxlogid;
unsigned int uxrecoff;
uint32 xlogid;
uint32 xlogseg;
XLogRecPtr locationpoint;
char xlogfilename[MAXFNAMELEN];
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is in progress"),
errhint("pg_xlogfile_name() cannot be executed during recovery.")));
locationstr = text_to_cstring(location);
if (sscanf(locationstr, "%X/%X", &uxlogid, &uxrecoff) != 2)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not parse transaction log location \"%s\"",
locationstr)));
locationpoint.xlogid = uxlogid;
locationpoint.xrecoff = uxrecoff;
XLByteToPrevSeg(locationpoint, xlogid, xlogseg);
XLogFileName(xlogfilename, ThisTimeLineID, xlogid, xlogseg);
PG_RETURN_TEXT_P(cstring_to_text(xlogfilename));
return LogwrtResult.Write;
}
/*

467
src/backend/access/transam/xlogfuncs.c Normal file
View File

@ -0,0 +1,467 @@
/*-------------------------------------------------------------------------
*
* xlogfuncs.c
*
* PostgreSQL transaction log manager user interface functions
*
* This file contains WAL control and information functions.
*
*
* Portions Copyright (c) 1996-2011, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/backend/access/transam/xlogfuncs.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/xlog.h"
#include "access/xlog_internal.h"
#include "access/xlogutils.h"
#include "catalog/catalog.h"
#include "catalog/pg_type.h"
#include "funcapi.h"
#include "miscadmin.h"
#include "replication/walreceiver.h"
#include "storage/smgr.h"
#include "utils/builtins.h"
#include "utils/guc.h"
#include "utils/timestamp.h"
/*
* pg_start_backup: set up for taking an on-line backup dump
*
* Essentially what this does is to create a backup label file in $PGDATA,
* where it will be archived as part of the backup dump. The label file
* contains the user-supplied label string (typically this would be used
* to tell where the backup dump will be stored) and the starting time and
* starting WAL location for the dump.
*/
Datum
pg_start_backup(PG_FUNCTION_ARGS)
{
text *backupid = PG_GETARG_TEXT_P(0);
bool fast = PG_GETARG_BOOL(1);
char *backupidstr;
XLogRecPtr startpoint;
char startxlogstr[MAXFNAMELEN];
backupidstr = text_to_cstring(backupid);
startpoint = do_pg_start_backup(backupidstr, fast, NULL);
snprintf(startxlogstr, sizeof(startxlogstr), "%X/%X",
startpoint.xlogid, startpoint.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(startxlogstr));
}
/*
* pg_stop_backup: finish taking an on-line backup dump
*
* We write an end-of-backup WAL record, and remove the backup label file
* created by pg_start_backup, creating a backup history file in pg_xlog
* instead (whence it will immediately be archived). The backup history file
* contains the same info found in the label file, plus the backup-end time
* and WAL location. Before 9.0, the backup-end time was read from the backup
* history file at the beginning of archive recovery, but we now use the WAL
* record for that and the file is for informational and debug purposes only.
*
* Note: different from CancelBackup which just cancels online backup mode.
*/
Datum
pg_stop_backup(PG_FUNCTION_ARGS)
{
XLogRecPtr stoppoint;
char stopxlogstr[MAXFNAMELEN];
stoppoint = do_pg_stop_backup(NULL, true);
snprintf(stopxlogstr, sizeof(stopxlogstr), "%X/%X",
stoppoint.xlogid, stoppoint.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(stopxlogstr));
}
/*
* pg_switch_xlog: switch to next xlog file
*/
Datum
pg_switch_xlog(PG_FUNCTION_ARGS)
{
XLogRecPtr switchpoint;
char location[MAXFNAMELEN];
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to switch transaction log files"))));
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is in progress"),
errhint("WAL control functions cannot be executed during recovery.")));
switchpoint = RequestXLogSwitch();
/*
* As a convenience, return the WAL location of the switch record
*/
snprintf(location, sizeof(location), "%X/%X",
switchpoint.xlogid, switchpoint.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
}
/*
* pg_create_restore_point: a named point for restore
*/
Datum
pg_create_restore_point(PG_FUNCTION_ARGS)
{
text *restore_name = PG_GETARG_TEXT_P(0);
char *restore_name_str;
XLogRecPtr restorepoint;
char location[MAXFNAMELEN];
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to create a restore point"))));
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
(errmsg("recovery is in progress"),
errhint("WAL control functions cannot be executed during recovery."))));
if (!XLogIsNeeded())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("WAL level not sufficient for creating a restore point"),
errhint("wal_level must be set to \"archive\" or \"hot_standby\" at server start.")));
restore_name_str = text_to_cstring(restore_name);
if (strlen(restore_name_str) >= MAXFNAMELEN)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("value too long for restore point (maximum %d characters)", MAXFNAMELEN - 1)));
restorepoint = XLogRestorePoint(restore_name_str);
/*
* As a convenience, return the WAL location of the restore point record
*/
snprintf(location, sizeof(location), "%X/%X",
restorepoint.xlogid, restorepoint.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
}
/*
* Report the current WAL write location (same format as pg_start_backup etc)
*
* This is useful for determining how much of WAL is visible to an external
* archiving process. Note that the data before this point is written out
* to the kernel, but is not necessarily synced to disk.
*/
Datum
pg_current_xlog_location(PG_FUNCTION_ARGS)
{
XLogRecPtr current_recptr;
char location[MAXFNAMELEN];
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is in progress"),
errhint("WAL control functions cannot be executed during recovery.")));
current_recptr = GetXLogWriteRecPtr();
snprintf(location, sizeof(location), "%X/%X",
current_recptr.xlogid, current_recptr.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
}
/*
* Report the current WAL insert location (same format as pg_start_backup etc)
*
* This function is mostly for debugging purposes.
*/
Datum
pg_current_xlog_insert_location(PG_FUNCTION_ARGS)
{
XLogRecPtr current_recptr;
char location[MAXFNAMELEN];
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is in progress"),
errhint("WAL control functions cannot be executed during recovery.")));
current_recptr = GetXLogInsertRecPtr(true);
snprintf(location, sizeof(location), "%X/%X",
current_recptr.xlogid, current_recptr.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
}
/*
* Report the last WAL receive location (same format as pg_start_backup etc)
*
* This is useful for determining how much of WAL is guaranteed to be received
* and synced to disk by walreceiver.
*/
Datum
pg_last_xlog_receive_location(PG_FUNCTION_ARGS)
{
XLogRecPtr recptr;
char location[MAXFNAMELEN];
recptr = GetWalRcvWriteRecPtr(NULL);
if (recptr.xlogid == 0 && recptr.xrecoff == 0)
PG_RETURN_NULL();
snprintf(location, sizeof(location), "%X/%X",
recptr.xlogid, recptr.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
}
/*
* Report the last WAL replay location (same format as pg_start_backup etc)
*
* This is useful for determining how much of WAL is visible to read-only
* connections during recovery.
*/
Datum
pg_last_xlog_replay_location(PG_FUNCTION_ARGS)
{
XLogRecPtr recptr;
char location[MAXFNAMELEN];
recptr = GetXLogReplayRecPtr(NULL);
if (recptr.xlogid == 0 && recptr.xrecoff == 0)
PG_RETURN_NULL();
snprintf(location, sizeof(location), "%X/%X",
recptr.xlogid, recptr.xrecoff);
PG_RETURN_TEXT_P(cstring_to_text(location));
}
/*
* Compute an xlog file name and decimal byte offset given a WAL location,
* such as is returned by pg_stop_backup() or pg_xlog_switch().
*
* Note that a location exactly at a segment boundary is taken to be in
* the previous segment. This is usually the right thing, since the
* expected usage is to determine which xlog file(s) are ready to archive.
*/
Datum
pg_xlogfile_name_offset(PG_FUNCTION_ARGS)
{
text *location = PG_GETARG_TEXT_P(0);
char *locationstr;
unsigned int uxlogid;
unsigned int uxrecoff;
uint32 xlogid;
uint32 xlogseg;
uint32 xrecoff;
XLogRecPtr locationpoint;
char xlogfilename[MAXFNAMELEN];
Datum values[2];
bool isnull[2];
TupleDesc resultTupleDesc;
HeapTuple resultHeapTuple;
Datum result;
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is in progress"),
errhint("pg_xlogfile_name_offset() cannot be executed during recovery.")));
/*
* Read input and parse
*/
locationstr = text_to_cstring(location);
if (sscanf(locationstr, "%X/%X", &uxlogid, &uxrecoff) != 2)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not parse transaction log location \"%s\"",
locationstr)));
locationpoint.xlogid = uxlogid;
locationpoint.xrecoff = uxrecoff;
/*
* Construct a tuple descriptor for the result row. This must match this
* function's pg_proc entry!
*/
resultTupleDesc = CreateTemplateTupleDesc(2, false);
TupleDescInitEntry(resultTupleDesc, (AttrNumber) 1, "file_name",
TEXTOID, -1, 0);
TupleDescInitEntry(resultTupleDesc, (AttrNumber) 2, "file_offset",
INT4OID, -1, 0);
resultTupleDesc = BlessTupleDesc(resultTupleDesc);
/*
* xlogfilename
*/
XLByteToPrevSeg(locationpoint, xlogid, xlogseg);
XLogFileName(xlogfilename, ThisTimeLineID, xlogid, xlogseg);
values[0] = CStringGetTextDatum(xlogfilename);
isnull[0] = false;
/*
* offset
*/
xrecoff = locationpoint.xrecoff - xlogseg * XLogSegSize;
values[1] = UInt32GetDatum(xrecoff);
isnull[1] = false;
/*
* Tuple jam: Having first prepared your Datums, then squash together
*/
resultHeapTuple = heap_form_tuple(resultTupleDesc, values, isnull);
result = HeapTupleGetDatum(resultHeapTuple);
PG_RETURN_DATUM(result);
}
/*
* Compute an xlog file name given a WAL location,
* such as is returned by pg_stop_backup() or pg_xlog_switch().
*/
Datum
pg_xlogfile_name(PG_FUNCTION_ARGS)
{
text *location = PG_GETARG_TEXT_P(0);
char *locationstr;
unsigned int uxlogid;
unsigned int uxrecoff;
uint32 xlogid;
uint32 xlogseg;
XLogRecPtr locationpoint;
char xlogfilename[MAXFNAMELEN];
if (RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is in progress"),
errhint("pg_xlogfile_name() cannot be executed during recovery.")));
locationstr = text_to_cstring(location);
if (sscanf(locationstr, "%X/%X", &uxlogid, &uxrecoff) != 2)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not parse transaction log location \"%s\"",
locationstr)));
locationpoint.xlogid = uxlogid;
locationpoint.xrecoff = uxrecoff;
XLByteToPrevSeg(locationpoint, xlogid, xlogseg);
XLogFileName(xlogfilename, ThisTimeLineID, xlogid, xlogseg);
PG_RETURN_TEXT_P(cstring_to_text(xlogfilename));
}
/*
* pg_xlog_replay_pause - pause recovery now
*/
Datum
pg_xlog_replay_pause(PG_FUNCTION_ARGS)
{
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to control recovery"))));
if (!RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is not in progress"),
errhint("Recovery control functions can only be executed during recovery.")));
SetRecoveryPause(true);
PG_RETURN_VOID();
}
/*
* pg_xlog_replay_resume - resume recovery now
*/
Datum
pg_xlog_replay_resume(PG_FUNCTION_ARGS)
{
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to control recovery"))));
if (!RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is not in progress"),
errhint("Recovery control functions can only be executed during recovery.")));
SetRecoveryPause(false);
PG_RETURN_VOID();
}
/*
* pg_is_xlog_replay_paused
*/
Datum
pg_is_xlog_replay_paused(PG_FUNCTION_ARGS)
{
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to control recovery"))));
if (!RecoveryInProgress())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("recovery is not in progress"),
errhint("Recovery control functions can only be executed during recovery.")));
PG_RETURN_BOOL(RecoveryIsPaused());
}
/*
* Returns timestamp of latest processed commit/abort record.
*
* When the server has been started normally without recovery the function
* returns NULL.
*/
Datum
pg_last_xact_replay_timestamp(PG_FUNCTION_ARGS)
{
TimestampTz xtime;
xtime = GetLatestXTime();
if (xtime == 0)
PG_RETURN_NULL();
PG_RETURN_TIMESTAMPTZ(xtime);
}
/*
* Returns bool with current recovery mode, a global state.
*/
Datum
pg_is_in_recovery(PG_FUNCTION_ARGS)
{
PG_RETURN_BOOL(RecoveryInProgress());
}

5
src/include/access/xlog.h
View File

@ -293,6 +293,11 @@ extern bool XLogInsertAllowed(void);
extern void GetXLogReceiptTime(TimestampTz *rtime, bool *fromStream);
extern XLogRecPtr GetXLogReplayRecPtr(XLogRecPtr *restoreLastRecPtr);
extern XLogRecPtr GetStandbyFlushRecPtr(void);
extern XLogRecPtr GetXLogInsertRecPtr(bool needlock);
extern XLogRecPtr GetXLogWriteRecPtr(void);
extern bool RecoveryIsPaused(void);
extern void SetRecoveryPause(bool recoveryPause);
extern TimestampTz GetLatestXTime(void);
extern void UpdateControlFile(void);
extern uint64 GetSystemIdentifier(void);