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dbcommands_xlog.h File Reference
#include "access/xlogreader.h"
#include "lib/stringinfo.h"
Include dependency graph for dbcommands_xlog.h:
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Data Structures

struct  xl_dbase_create_file_copy_rec
 
struct  xl_dbase_create_wal_log_rec
 
struct  xl_dbase_drop_rec
 

Macros

#define XLOG_DBASE_CREATE_FILE_COPY   0x00
 
#define XLOG_DBASE_CREATE_WAL_LOG   0x10
 
#define XLOG_DBASE_DROP   0x20
 
#define MinSizeOfDbaseDropRec   offsetof(xl_dbase_drop_rec, tablespace_ids)
 

Typedefs

typedef struct xl_dbase_create_file_copy_rec xl_dbase_create_file_copy_rec
 
typedef struct xl_dbase_create_wal_log_rec xl_dbase_create_wal_log_rec
 
typedef struct xl_dbase_drop_rec xl_dbase_drop_rec
 

Functions

void dbase_redo (XLogReaderState *record)
 
void dbase_desc (StringInfo buf, XLogReaderState *record)
 
const char * dbase_identify (uint8 info)
 

Macro Definition Documentation

◆ MinSizeOfDbaseDropRec

#define MinSizeOfDbaseDropRec   offsetof(xl_dbase_drop_rec, tablespace_ids)

Definition at line 54 of file dbcommands_xlog.h.

◆ XLOG_DBASE_CREATE_FILE_COPY

#define XLOG_DBASE_CREATE_FILE_COPY   0x00

Definition at line 21 of file dbcommands_xlog.h.

◆ XLOG_DBASE_CREATE_WAL_LOG

#define XLOG_DBASE_CREATE_WAL_LOG   0x10

Definition at line 22 of file dbcommands_xlog.h.

◆ XLOG_DBASE_DROP

#define XLOG_DBASE_DROP   0x20

Definition at line 23 of file dbcommands_xlog.h.

Typedef Documentation

◆ xl_dbase_create_file_copy_rec

◆ xl_dbase_create_wal_log_rec

◆ xl_dbase_drop_rec

Function Documentation

◆ dbase_desc()

void dbase_desc ( StringInfo  buf,
XLogReaderState record 
)

Definition at line 22 of file dbasedesc.c.

23 {
24  char *rec = XLogRecGetData(record);
25  uint8 info = XLogRecGetInfo(record) & ~XLR_INFO_MASK;
26 
27  if (info == XLOG_DBASE_CREATE_FILE_COPY)
28  {
31 
32  appendStringInfo(buf, "copy dir %u/%u to %u/%u",
33  xlrec->src_tablespace_id, xlrec->src_db_id,
34  xlrec->tablespace_id, xlrec->db_id);
35  }
36  else if (info == XLOG_DBASE_CREATE_WAL_LOG)
37  {
40 
41  appendStringInfo(buf, "create dir %u/%u",
42  xlrec->tablespace_id, xlrec->db_id);
43  }
44  else if (info == XLOG_DBASE_DROP)
45  {
46  xl_dbase_drop_rec *xlrec = (xl_dbase_drop_rec *) rec;
47  int i;
48 
50  for (i = 0; i < xlrec->ntablespaces; i++)
51  appendStringInfo(buf, " %u/%u",
52  xlrec->tablespace_ids[i], xlrec->db_id);
53  }
54 }
unsigned char uint8
Definition: c.h:504
#define XLOG_DBASE_CREATE_WAL_LOG
#define XLOG_DBASE_DROP
#define XLOG_DBASE_CREATE_FILE_COPY
int i
Definition: isn.c:73
static char * buf
Definition: pg_test_fsync.c:73
void appendStringInfo(StringInfo str, const char *fmt,...)
Definition: stringinfo.c:97
void appendStringInfoString(StringInfo str, const char *s)
Definition: stringinfo.c:182
Oid tablespace_ids[FLEXIBLE_ARRAY_MEMBER]
#define XLogRecGetInfo(decoder)
Definition: xlogreader.h:410
#define XLogRecGetData(decoder)
Definition: xlogreader.h:415
#define XLR_INFO_MASK
Definition: xlogrecord.h:62

References appendStringInfo(), appendStringInfoString(), buf, xl_dbase_create_file_copy_rec::db_id, xl_dbase_create_wal_log_rec::db_id, xl_dbase_drop_rec::db_id, i, xl_dbase_drop_rec::ntablespaces, xl_dbase_create_file_copy_rec::src_db_id, xl_dbase_create_file_copy_rec::src_tablespace_id, xl_dbase_create_file_copy_rec::tablespace_id, xl_dbase_create_wal_log_rec::tablespace_id, xl_dbase_drop_rec::tablespace_ids, XLOG_DBASE_CREATE_FILE_COPY, XLOG_DBASE_CREATE_WAL_LOG, XLOG_DBASE_DROP, XLogRecGetData, XLogRecGetInfo, and XLR_INFO_MASK.

◆ dbase_identify()

const char* dbase_identify ( uint8  info)

Definition at line 57 of file dbasedesc.c.

58 {
59  const char *id = NULL;
60 
61  switch (info & ~XLR_INFO_MASK)
62  {
64  id = "CREATE_FILE_COPY";
65  break;
67  id = "CREATE_WAL_LOG";
68  break;
69  case XLOG_DBASE_DROP:
70  id = "DROP";
71  break;
72  }
73 
74  return id;
75 }

References XLOG_DBASE_CREATE_FILE_COPY, XLOG_DBASE_CREATE_WAL_LOG, XLOG_DBASE_DROP, and XLR_INFO_MASK.

◆ dbase_redo()

void dbase_redo ( XLogReaderState record)

Definition at line 3250 of file dbcommands.c.

3251 {
3252  uint8 info = XLogRecGetInfo(record) & ~XLR_INFO_MASK;
3253 
3254  /* Backup blocks are not used in dbase records */
3255  Assert(!XLogRecHasAnyBlockRefs(record));
3256 
3257  if (info == XLOG_DBASE_CREATE_FILE_COPY)
3258  {
3261  char *src_path;
3262  char *dst_path;
3263  char *parent_path;
3264  struct stat st;
3265 
3266  src_path = GetDatabasePath(xlrec->src_db_id, xlrec->src_tablespace_id);
3267  dst_path = GetDatabasePath(xlrec->db_id, xlrec->tablespace_id);
3268 
3269  /*
3270  * Our theory for replaying a CREATE is to forcibly drop the target
3271  * subdirectory if present, then re-copy the source data. This may be
3272  * more work than needed, but it is simple to implement.
3273  */
3274  if (stat(dst_path, &st) == 0 && S_ISDIR(st.st_mode))
3275  {
3276  if (!rmtree(dst_path, true))
3277  /* If this failed, copydir() below is going to error. */
3278  ereport(WARNING,
3279  (errmsg("some useless files may be left behind in old database directory \"%s\"",
3280  dst_path)));
3281  }
3282 
3283  /*
3284  * If the parent of the target path doesn't exist, create it now. This
3285  * enables us to create the target underneath later.
3286  */
3287  parent_path = pstrdup(dst_path);
3288  get_parent_directory(parent_path);
3289  if (stat(parent_path, &st) < 0)
3290  {
3291  if (errno != ENOENT)
3292  ereport(FATAL,
3293  errmsg("could not stat directory \"%s\": %m",
3294  dst_path));
3295 
3296  /* create the parent directory if needed and valid */
3297  recovery_create_dbdir(parent_path, true);
3298  }
3299  pfree(parent_path);
3300 
3301  /*
3302  * There's a case where the copy source directory is missing for the
3303  * same reason above. Create the empty source directory so that
3304  * copydir below doesn't fail. The directory will be dropped soon by
3305  * recovery.
3306  */
3307  if (stat(src_path, &st) < 0 && errno == ENOENT)
3308  recovery_create_dbdir(src_path, false);
3309 
3310  /*
3311  * Force dirty buffers out to disk, to ensure source database is
3312  * up-to-date for the copy.
3313  */
3315 
3316  /* Close all smgr fds in all backends. */
3318 
3319  /*
3320  * Copy this subdirectory to the new location
3321  *
3322  * We don't need to copy subdirectories
3323  */
3324  copydir(src_path, dst_path, false);
3325 
3326  pfree(src_path);
3327  pfree(dst_path);
3328  }
3329  else if (info == XLOG_DBASE_CREATE_WAL_LOG)
3330  {
3333  char *dbpath;
3334  char *parent_path;
3335 
3336  dbpath = GetDatabasePath(xlrec->db_id, xlrec->tablespace_id);
3337 
3338  /* create the parent directory if needed and valid */
3339  parent_path = pstrdup(dbpath);
3340  get_parent_directory(parent_path);
3341  recovery_create_dbdir(parent_path, true);
3342 
3343  /* Create the database directory with the version file. */
3344  CreateDirAndVersionFile(dbpath, xlrec->db_id, xlrec->tablespace_id,
3345  true);
3346  pfree(dbpath);
3347  }
3348  else if (info == XLOG_DBASE_DROP)
3349  {
3350  xl_dbase_drop_rec *xlrec = (xl_dbase_drop_rec *) XLogRecGetData(record);
3351  char *dst_path;
3352  int i;
3353 
3354  if (InHotStandby)
3355  {
3356  /*
3357  * Lock database while we resolve conflicts to ensure that
3358  * InitPostgres() cannot fully re-execute concurrently. This
3359  * avoids backends re-connecting automatically to same database,
3360  * which can happen in some cases.
3361  *
3362  * This will lock out walsenders trying to connect to db-specific
3363  * slots for logical decoding too, so it's safe for us to drop
3364  * slots.
3365  */
3366  LockSharedObjectForSession(DatabaseRelationId, xlrec->db_id, 0, AccessExclusiveLock);
3368  }
3369 
3370  /* Drop any database-specific replication slots */
3372 
3373  /* Drop pages for this database that are in the shared buffer cache */
3374  DropDatabaseBuffers(xlrec->db_id);
3375 
3376  /* Also, clean out any fsync requests that might be pending in md.c */
3378 
3379  /* Clean out the xlog relcache too */
3380  XLogDropDatabase(xlrec->db_id);
3381 
3382  /* Close all smgr fds in all backends. */
3384 
3385  for (i = 0; i < xlrec->ntablespaces; i++)
3386  {
3387  dst_path = GetDatabasePath(xlrec->db_id, xlrec->tablespace_ids[i]);
3388 
3389  /* And remove the physical files */
3390  if (!rmtree(dst_path, true))
3391  ereport(WARNING,
3392  (errmsg("some useless files may be left behind in old database directory \"%s\"",
3393  dst_path)));
3394  pfree(dst_path);
3395  }
3396 
3397  if (InHotStandby)
3398  {
3399  /*
3400  * Release locks prior to commit. XXX There is a race condition
3401  * here that may allow backends to reconnect, but the window for
3402  * this is small because the gap between here and commit is mostly
3403  * fairly small and it is unlikely that people will be dropping
3404  * databases that we are trying to connect to anyway.
3405  */
3406  UnlockSharedObjectForSession(DatabaseRelationId, xlrec->db_id, 0, AccessExclusiveLock);
3407  }
3408  }
3409  else
3410  elog(PANIC, "dbase_redo: unknown op code %u", info);
3411 }
void DropDatabaseBuffers(Oid dbid)
Definition: bufmgr.c:4375
void FlushDatabaseBuffers(Oid dbid)
Definition: bufmgr.c:4834
#define Assert(condition)
Definition: c.h:858
void copydir(const char *fromdir, const char *todir, bool recurse)
Definition: copydir.c:37
static void CreateDirAndVersionFile(char *dbpath, Oid dbid, Oid tsid, bool isRedo)
Definition: dbcommands.c:456
static void recovery_create_dbdir(char *path, bool only_tblspc)
Definition: dbcommands.c:3221
int errmsg(const char *fmt,...)
Definition: elog.c:1070
#define FATAL
Definition: elog.h:41
#define WARNING
Definition: elog.h:36
#define PANIC
Definition: elog.h:42
#define elog(elevel,...)
Definition: elog.h:224
#define ereport(elevel,...)
Definition: elog.h:149
void UnlockSharedObjectForSession(Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
Definition: lmgr.c:1181
void LockSharedObjectForSession(Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
Definition: lmgr.c:1163
#define AccessExclusiveLock
Definition: lockdefs.h:43
char * pstrdup(const char *in)
Definition: mcxt.c:1695
void pfree(void *pointer)
Definition: mcxt.c:1520
void ForgetDatabaseSyncRequests(Oid dbid)
Definition: md.c:1428
void get_parent_directory(char *path)
Definition: path.c:976
void WaitForProcSignalBarrier(uint64 generation)
Definition: procsignal.c:389
uint64 EmitProcSignalBarrier(ProcSignalBarrierType type)
Definition: procsignal.c:329
@ PROCSIGNAL_BARRIER_SMGRRELEASE
Definition: procsignal.h:56
char * GetDatabasePath(Oid dbOid, Oid spcOid)
Definition: relpath.c:110
bool rmtree(const char *path, bool rmtopdir)
Definition: rmtree.c:50
void ReplicationSlotsDropDBSlots(Oid dboid)
Definition: slot.c:1270
void ResolveRecoveryConflictWithDatabase(Oid dbid)
Definition: standby.c:568
#define stat
Definition: win32_port.h:284
#define S_ISDIR(m)
Definition: win32_port.h:325
#define XLogRecHasAnyBlockRefs(decoder)
Definition: xlogreader.h:417
void XLogDropDatabase(Oid dbid)
Definition: xlogutils.c:652
#define InHotStandby
Definition: xlogutils.h:57

References AccessExclusiveLock, Assert, copydir(), CreateDirAndVersionFile(), xl_dbase_create_file_copy_rec::db_id, xl_dbase_create_wal_log_rec::db_id, xl_dbase_drop_rec::db_id, DropDatabaseBuffers(), elog, EmitProcSignalBarrier(), ereport, errmsg(), FATAL, FlushDatabaseBuffers(), ForgetDatabaseSyncRequests(), get_parent_directory(), GetDatabasePath(), i, InHotStandby, LockSharedObjectForSession(), xl_dbase_drop_rec::ntablespaces, PANIC, pfree(), PROCSIGNAL_BARRIER_SMGRRELEASE, pstrdup(), recovery_create_dbdir(), ReplicationSlotsDropDBSlots(), ResolveRecoveryConflictWithDatabase(), rmtree(), S_ISDIR, xl_dbase_create_file_copy_rec::src_db_id, xl_dbase_create_file_copy_rec::src_tablespace_id, stat::st_mode, stat, xl_dbase_create_file_copy_rec::tablespace_id, xl_dbase_create_wal_log_rec::tablespace_id, xl_dbase_drop_rec::tablespace_ids, UnlockSharedObjectForSession(), WaitForProcSignalBarrier(), WARNING, XLOG_DBASE_CREATE_FILE_COPY, XLOG_DBASE_CREATE_WAL_LOG, XLOG_DBASE_DROP, XLogDropDatabase(), XLogRecGetData, XLogRecGetInfo, XLogRecHasAnyBlockRefs, and XLR_INFO_MASK.