@ -23,7 +23,7 @@
* Portions Copyright ( c ) 1996 - 2006 , PostgreSQL Global Development Group
* Portions Copyright ( c ) 1994 , Regents of the University of California
*
* $ PostgreSQL : pgsql / src / bin / pg_resetxlog / pg_resetxlog . c , v 1.53 2006 / 10 / 04 00 : 30 : 05 momjian Exp $
* $ PostgreSQL : pgsql / src / bin / pg_resetxlog / pg_resetxlog . c , v 1.54 2006 / 12 / 08 19 : 50 : 53 tgl Exp $
*
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
*/
@ -60,6 +60,7 @@ static bool ReadControlFile(void);
static void GuessControlValues ( void ) ;
static void PrintControlValues ( bool guessed ) ;
static void RewriteControlFile ( void ) ;
static void FindEndOfXLOG ( void ) ;
static void KillExistingXLOG ( void ) ;
static void WriteEmptyXLOG ( void ) ;
static void usage ( void ) ;
@ -283,6 +284,11 @@ main(int argc, char *argv[])
if ( ! ReadControlFile ( ) )
GuessControlValues ( ) ;
/*
* Also look at existing segment files to set up newXlogId / newXlogSeg
*/
FindEndOfXLOG ( ) ;
/*
* Adjust fields if required by switches . ( Do this now so that printout ,
* if any , includes these values . )
@ -305,12 +311,12 @@ main(int argc, char *argv[])
if ( minXlogTli > ControlFile . checkPointCopy . ThisTimeLineID )
ControlFile . checkPointCopy . ThisTimeLineID = minXlogTli ;
if ( minXlogId > ControlFile . logId | |
( minXlogId = = ControlFile . logId & &
minXlogSeg > ControlFile . logSeg ) )
if ( minXlogId > newX logId| |
( minXlogId = = newX logId& &
minXlogSeg > newX logSeg) )
{
ControlFile . logId = minXlogId ;
ControlFile . logSeg = minXlogSeg ;
newX logId= minXlogId ;
newX logSeg= minXlogSeg ;
}
/*
@ -469,8 +475,6 @@ GuessControlValues(void)
ControlFile . state = DB_SHUTDOWNED ;
ControlFile . time = time ( NULL ) ;
ControlFile . logId = 0 ;
ControlFile . logSeg = 1 ;
ControlFile . checkPoint = ControlFile . checkPointCopy . redo ;
ControlFile . maxAlign = MAXIMUM_ALIGNOF ;
@ -533,16 +537,16 @@ PrintControlValues(bool guessed)
snprintf ( sysident_str , sizeof ( sysident_str ) , UINT64_FORMAT ,
ControlFile . system_identifier ) ;
printf ( _ ( " First log file ID for new XLOG: %u \n " ) ,
newXlogId ) ;
printf ( _ ( " First log file segment for new XLOG: %u \n " ) ,
newXlogSeg ) ;
printf ( _ ( " pg_control version number: %u \n " ) ,
ControlFile . pg_control_version ) ;
printf ( _ ( " Catalog version number: %u \n " ) ,
ControlFile . catalog_version_no ) ;
printf ( _ ( " Database system identifier: %s \n " ) ,
sysident_str ) ;
printf ( _ ( " Current log file ID: %u \n " ) ,
ControlFile . logId ) ;
printf ( _ ( " Next log file segment: %u \n " ) ,
ControlFile . logSeg ) ;
printf ( _ ( " Latest checkpoint's TimeLineID: %u \n " ) ,
ControlFile . checkPointCopy . ThisTimeLineID ) ;
printf ( _ ( " Latest checkpoint's NextXID: %u/%u \n " ) ,
@ -590,22 +594,9 @@ RewriteControlFile(void)
char buffer [ PG_CONTROL_SIZE ] ; /* need not be aligned */
/*
* Adjust fields as needed to force an empty XLOG starting at the next
* available segment .
* Adjust fields as needed to force an empty XLOG starting at
* newXlogId / newXlogSeg .
*/
newXlogId = ControlFile . logId ;
newXlogSeg = ControlFile . logSeg ;
/* adjust in case we are changing segment size */
newXlogSeg * = ControlFile . xlog_seg_size ;
newXlogSeg = ( newXlogSeg + XLogSegSize - 1 ) / XLogSegSize ;
/* be sure we wrap around correctly at end of a logfile */
NextLogSeg ( newXlogId , newXlogSeg ) ;
/* Now we can force the recorded xlog seg size to the right thing. */
ControlFile . xlog_seg_size = XLogSegSize ;
ControlFile . checkPointCopy . redo . xlogid = newXlogId ;
ControlFile . checkPointCopy . redo . xrecoff =
newXlogSeg * XLogSegSize + SizeOfXLogLongPHD ;
@ -614,14 +605,15 @@ RewriteControlFile(void)
ControlFile . state = DB_SHUTDOWNED ;
ControlFile . time = time ( NULL ) ;
ControlFile . logId = newXlogId ;
ControlFile . logSeg = newXlogSeg + 1 ;
ControlFile . checkPoint = ControlFile . checkPointCopy . redo ;
ControlFile . prevCheckPoint . xlogid = 0 ;
ControlFile . prevCheckPoint . xrecoff = 0 ;
ControlFile . minRecoveryPoint . xlogid = 0 ;
ControlFile . minRecoveryPoint . xrecoff = 0 ;
/* Now we can force the recorded xlog seg size to the right thing. */
ControlFile . xlog_seg_size = XLogSegSize ;
/* Contents are protected with a CRC */
INIT_CRC32 ( ControlFile . crc ) ;
COMP_CRC32 ( ControlFile . crc ,
@ -680,6 +672,97 @@ RewriteControlFile(void)
}
/*
* Scan existing XLOG files and determine the highest existing WAL address
*
* On entry , ControlFile . checkPointCopy . redo and ControlFile . xlog_seg_size
* are assumed valid ( note that we allow the old xlog seg size to differ
* from what we ' re using ) . On exit , newXlogId and newXlogSeg are set to
* suitable values for the beginning of replacement WAL ( in our seg size ) .
*/
static void
FindEndOfXLOG ( void )
{
DIR * xldir ;
struct dirent * xlde ;
/*
* Initialize the max ( ) computation using the last checkpoint address
* from old pg_control . Note that for the moment we are working with
* segment numbering according to the old xlog seg size .
*/
newXlogId = ControlFile . checkPointCopy . redo . xlogid ;
newXlogSeg = ControlFile . checkPointCopy . redo . xrecoff / ControlFile . xlog_seg_size ;
/*
* Scan the pg_xlog directory to find existing WAL segment files .
* We assume any present have been used ; in most scenarios this should
* be conservative , because of xlog . c ' s attempts to pre - create files .
*/
xldir = opendir ( XLOGDIR ) ;
if ( xldir = = NULL )
{
fprintf ( stderr , _ ( " %s: could not open directory \" %s \" : %s \n " ) ,
progname , XLOGDIR , strerror ( errno ) ) ;
exit ( 1 ) ;
}
errno = 0 ;
while ( ( xlde = readdir ( xldir ) ) ! = NULL )
{
if ( strlen ( xlde - > d_name ) = = 24 & &
strspn ( xlde - > d_name , " 0123456789ABCDEF " ) = = 24 )
{
unsigned int tli ,
log ,
seg ;
sscanf ( xlde - > d_name , " %08X%08X%08X " , & tli , & log , & seg ) ;
/*
* Note : we take the max of all files found , regardless of their
* timelines . Another possibility would be to ignore files of
* timelines other than the target TLI , but this seems safer .
* Better too large a result than too small . . .
*/
if ( log > newXlogId | |
( log = = newXlogId & & seg > newXlogSeg ) )
{
newXlogId = log ;
newXlogSeg = seg ;
}
}
errno = 0 ;
}
# ifdef WIN32
/*
* This fix is in mingw cvs ( runtime / mingwex / dirent . c rev 1.4 ) , but not in
* released version
*/
if ( GetLastError ( ) = = ERROR_NO_MORE_FILES )
errno = 0 ;
# endif
if ( errno )
{
fprintf ( stderr , _ ( " %s: could not read from directory \" %s \" : %s \n " ) ,
progname , XLOGDIR , strerror ( errno ) ) ;
exit ( 1 ) ;
}
closedir ( xldir ) ;
/*
* Finally , convert to new xlog seg size , and advance by one to ensure
* we are in virgin territory .
*/
newXlogSeg * = ControlFile . xlog_seg_size ;
newXlogSeg = ( newXlogSeg + XLogSegSize - 1 ) / XLogSegSize ;
/* be sure we wrap around correctly at end of a logfile */
NextLogSeg ( newXlogId , newXlogSeg ) ;
}
/*
* Remove existing XLOG files
*/
Tom Lane
19 years ago