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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:491
#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 3249 of file dbcommands.c.

3250 {
3251  uint8 info = XLogRecGetInfo(record) & ~XLR_INFO_MASK;
3252 
3253  /* Backup blocks are not used in dbase records */
3254  Assert(!XLogRecHasAnyBlockRefs(record));
3255 
3256  if (info == XLOG_DBASE_CREATE_FILE_COPY)
3257  {
3260  char *src_path;
3261  char *dst_path;
3262  char *parent_path;
3263  struct stat st;
3264 
3265  src_path = GetDatabasePath(xlrec->src_db_id, xlrec->src_tablespace_id);
3266  dst_path = GetDatabasePath(xlrec->db_id, xlrec->tablespace_id);
3267 
3268  /*
3269  * Our theory for replaying a CREATE is to forcibly drop the target
3270  * subdirectory if present, then re-copy the source data. This may be
3271  * more work than needed, but it is simple to implement.
3272  */
3273  if (stat(dst_path, &st) == 0 && S_ISDIR(st.st_mode))
3274  {
3275  if (!rmtree(dst_path, true))
3276  /* If this failed, copydir() below is going to error. */
3277  ereport(WARNING,
3278  (errmsg("some useless files may be left behind in old database directory \"%s\"",
3279  dst_path)));
3280  }
3281 
3282  /*
3283  * If the parent of the target path doesn't exist, create it now. This
3284  * enables us to create the target underneath later.
3285  */
3286  parent_path = pstrdup(dst_path);
3287  get_parent_directory(parent_path);
3288  if (stat(parent_path, &st) < 0)
3289  {
3290  if (errno != ENOENT)
3291  ereport(FATAL,
3292  errmsg("could not stat directory \"%s\": %m",
3293  dst_path));
3294 
3295  /* create the parent directory if needed and valid */
3296  recovery_create_dbdir(parent_path, true);
3297  }
3298  pfree(parent_path);
3299 
3300  /*
3301  * There's a case where the copy source directory is missing for the
3302  * same reason above. Create the empty source directory so that
3303  * copydir below doesn't fail. The directory will be dropped soon by
3304  * recovery.
3305  */
3306  if (stat(src_path, &st) < 0 && errno == ENOENT)
3307  recovery_create_dbdir(src_path, false);
3308 
3309  /*
3310  * Force dirty buffers out to disk, to ensure source database is
3311  * up-to-date for the copy.
3312  */
3314 
3315  /* Close all sgmr fds in all backends. */
3317 
3318  /*
3319  * Copy this subdirectory to the new location
3320  *
3321  * We don't need to copy subdirectories
3322  */
3323  copydir(src_path, dst_path, false);
3324 
3325  pfree(src_path);
3326  pfree(dst_path);
3327  }
3328  else if (info == XLOG_DBASE_CREATE_WAL_LOG)
3329  {
3332  char *dbpath;
3333  char *parent_path;
3334 
3335  dbpath = GetDatabasePath(xlrec->db_id, xlrec->tablespace_id);
3336 
3337  /* create the parent directory if needed and valid */
3338  parent_path = pstrdup(dbpath);
3339  get_parent_directory(parent_path);
3340  recovery_create_dbdir(parent_path, true);
3341 
3342  /* Create the database directory with the version file. */
3343  CreateDirAndVersionFile(dbpath, xlrec->db_id, xlrec->tablespace_id,
3344  true);
3345  pfree(dbpath);
3346  }
3347  else if (info == XLOG_DBASE_DROP)
3348  {
3349  xl_dbase_drop_rec *xlrec = (xl_dbase_drop_rec *) XLogRecGetData(record);
3350  char *dst_path;
3351  int i;
3352 
3353  if (InHotStandby)
3354  {
3355  /*
3356  * Lock database while we resolve conflicts to ensure that
3357  * InitPostgres() cannot fully re-execute concurrently. This
3358  * avoids backends re-connecting automatically to same database,
3359  * which can happen in some cases.
3360  *
3361  * This will lock out walsenders trying to connect to db-specific
3362  * slots for logical decoding too, so it's safe for us to drop
3363  * slots.
3364  */
3365  LockSharedObjectForSession(DatabaseRelationId, xlrec->db_id, 0, AccessExclusiveLock);
3367  }
3368 
3369  /* Drop any database-specific replication slots */
3371 
3372  /* Drop pages for this database that are in the shared buffer cache */
3373  DropDatabaseBuffers(xlrec->db_id);
3374 
3375  /* Also, clean out any fsync requests that might be pending in md.c */
3377 
3378  /* Clean out the xlog relcache too */
3379  XLogDropDatabase(xlrec->db_id);
3380 
3381  /* Close all sgmr fds in all backends. */
3383 
3384  for (i = 0; i < xlrec->ntablespaces; i++)
3385  {
3386  dst_path = GetDatabasePath(xlrec->db_id, xlrec->tablespace_ids[i]);
3387 
3388  /* And remove the physical files */
3389  if (!rmtree(dst_path, true))
3390  ereport(WARNING,
3391  (errmsg("some useless files may be left behind in old database directory \"%s\"",
3392  dst_path)));
3393  pfree(dst_path);
3394  }
3395 
3396  if (InHotStandby)
3397  {
3398  /*
3399  * Release locks prior to commit. XXX There is a race condition
3400  * here that may allow backends to reconnect, but the window for
3401  * this is small because the gap between here and commit is mostly
3402  * fairly small and it is unlikely that people will be dropping
3403  * databases that we are trying to connect to anyway.
3404  */
3405  UnlockSharedObjectForSession(DatabaseRelationId, xlrec->db_id, 0, AccessExclusiveLock);
3406  }
3407  }
3408  else
3409  elog(PANIC, "dbase_redo: unknown op code %u", info);
3410 }
void DropDatabaseBuffers(Oid dbid)
Definition: bufmgr.c:4039
void FlushDatabaseBuffers(Oid dbid)
Definition: bufmgr.c:4498
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:3220
int errmsg(const char *fmt,...)
Definition: elog.c:1072
#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
Assert(fmt[strlen(fmt) - 1] !='\n')
void UnlockSharedObjectForSession(Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
Definition: lmgr.c:1143
void LockSharedObjectForSession(Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
Definition: lmgr.c:1125
#define AccessExclusiveLock
Definition: lockdefs.h:43
char * pstrdup(const char *in)
Definition: mcxt.c:1683
void pfree(void *pointer)
Definition: mcxt.c:1508
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:1243
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.