PostgreSQL Source Code  git master
dbcommands_xlog.h File Reference
#include "access/xlogreader.h"
#include "lib/stringinfo.h"
Include dependency graph for dbcommands_xlog.h:
This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

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:488
#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:67
void appendStringInfo(StringInfo str, const char *fmt,...)
Definition: stringinfo.c:91
void appendStringInfoString(StringInfo str, const char *s)
Definition: stringinfo.c:176
Oid tablespace_ids[FLEXIBLE_ARRAY_MEMBER]
#define XLogRecGetInfo(decoder)
Definition: xlogreader.h:409
#define XLogRecGetData(decoder)
Definition: xlogreader.h:414
#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 3088 of file dbcommands.c.

3089 {
3090  uint8 info = XLogRecGetInfo(record) & ~XLR_INFO_MASK;
3091 
3092  /* Backup blocks are not used in dbase records */
3093  Assert(!XLogRecHasAnyBlockRefs(record));
3094 
3095  if (info == XLOG_DBASE_CREATE_FILE_COPY)
3096  {
3099  char *src_path;
3100  char *dst_path;
3101  char *parent_path;
3102  struct stat st;
3103 
3104  src_path = GetDatabasePath(xlrec->src_db_id, xlrec->src_tablespace_id);
3105  dst_path = GetDatabasePath(xlrec->db_id, xlrec->tablespace_id);
3106 
3107  /*
3108  * Our theory for replaying a CREATE is to forcibly drop the target
3109  * subdirectory if present, then re-copy the source data. This may be
3110  * more work than needed, but it is simple to implement.
3111  */
3112  if (stat(dst_path, &st) == 0 && S_ISDIR(st.st_mode))
3113  {
3114  if (!rmtree(dst_path, true))
3115  /* If this failed, copydir() below is going to error. */
3116  ereport(WARNING,
3117  (errmsg("some useless files may be left behind in old database directory \"%s\"",
3118  dst_path)));
3119  }
3120 
3121  /*
3122  * If the parent of the target path doesn't exist, create it now. This
3123  * enables us to create the target underneath later.
3124  */
3125  parent_path = pstrdup(dst_path);
3126  get_parent_directory(parent_path);
3127  if (stat(parent_path, &st) < 0)
3128  {
3129  if (errno != ENOENT)
3130  ereport(FATAL,
3131  errmsg("could not stat directory \"%s\": %m",
3132  dst_path));
3133 
3134  /* create the parent directory if needed and valid */
3135  recovery_create_dbdir(parent_path, true);
3136  }
3137  pfree(parent_path);
3138 
3139  /*
3140  * There's a case where the copy source directory is missing for the
3141  * same reason above. Create the empty source directory so that
3142  * copydir below doesn't fail. The directory will be dropped soon by
3143  * recovery.
3144  */
3145  if (stat(src_path, &st) < 0 && errno == ENOENT)
3146  recovery_create_dbdir(src_path, false);
3147 
3148  /*
3149  * Force dirty buffers out to disk, to ensure source database is
3150  * up-to-date for the copy.
3151  */
3153 
3154  /* Close all sgmr fds in all backends. */
3156 
3157  /*
3158  * Copy this subdirectory to the new location
3159  *
3160  * We don't need to copy subdirectories
3161  */
3162  copydir(src_path, dst_path, false);
3163 
3164  pfree(src_path);
3165  pfree(dst_path);
3166  }
3167  else if (info == XLOG_DBASE_CREATE_WAL_LOG)
3168  {
3171  char *dbpath;
3172  char *parent_path;
3173 
3174  dbpath = GetDatabasePath(xlrec->db_id, xlrec->tablespace_id);
3175 
3176  /* create the parent directory if needed and valid */
3177  parent_path = pstrdup(dbpath);
3178  get_parent_directory(parent_path);
3179  recovery_create_dbdir(parent_path, true);
3180 
3181  /* Create the database directory with the version file. */
3182  CreateDirAndVersionFile(dbpath, xlrec->db_id, xlrec->tablespace_id,
3183  true);
3184  pfree(dbpath);
3185  }
3186  else if (info == XLOG_DBASE_DROP)
3187  {
3188  xl_dbase_drop_rec *xlrec = (xl_dbase_drop_rec *) XLogRecGetData(record);
3189  char *dst_path;
3190  int i;
3191 
3192  if (InHotStandby)
3193  {
3194  /*
3195  * Lock database while we resolve conflicts to ensure that
3196  * InitPostgres() cannot fully re-execute concurrently. This
3197  * avoids backends re-connecting automatically to same database,
3198  * which can happen in some cases.
3199  *
3200  * This will lock out walsenders trying to connect to db-specific
3201  * slots for logical decoding too, so it's safe for us to drop
3202  * slots.
3203  */
3204  LockSharedObjectForSession(DatabaseRelationId, xlrec->db_id, 0, AccessExclusiveLock);
3206  }
3207 
3208  /* Drop any database-specific replication slots */
3210 
3211  /* Drop pages for this database that are in the shared buffer cache */
3212  DropDatabaseBuffers(xlrec->db_id);
3213 
3214  /* Also, clean out any fsync requests that might be pending in md.c */
3216 
3217  /* Clean out the xlog relcache too */
3218  XLogDropDatabase(xlrec->db_id);
3219 
3220  /* Close all sgmr fds in all backends. */
3222 
3223  for (i = 0; i < xlrec->ntablespaces; i++)
3224  {
3225  dst_path = GetDatabasePath(xlrec->db_id, xlrec->tablespace_ids[i]);
3226 
3227  /* And remove the physical files */
3228  if (!rmtree(dst_path, true))
3229  ereport(WARNING,
3230  (errmsg("some useless files may be left behind in old database directory \"%s\"",
3231  dst_path)));
3232  pfree(dst_path);
3233  }
3234 
3235  if (InHotStandby)
3236  {
3237  /*
3238  * Release locks prior to commit. XXX There is a race condition
3239  * here that may allow backends to reconnect, but the window for
3240  * this is small because the gap between here and commit is mostly
3241  * fairly small and it is unlikely that people will be dropping
3242  * databases that we are trying to connect to anyway.
3243  */
3244  UnlockSharedObjectForSession(DatabaseRelationId, xlrec->db_id, 0, AccessExclusiveLock);
3245  }
3246  }
3247  else
3248  elog(PANIC, "dbase_redo: unknown op code %u", info);
3249 }
void DropDatabaseBuffers(Oid dbid)
Definition: bufmgr.c:3484
void FlushDatabaseBuffers(Oid dbid)
Definition: bufmgr.c:3941
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:457
static void recovery_create_dbdir(char *path, bool only_tblspc)
Definition: dbcommands.c:3059
int errmsg(const char *fmt,...)
Definition: elog.c:1069
#define FATAL
Definition: elog.h:41
#define WARNING
Definition: elog.h:36
#define PANIC
Definition: elog.h:42
#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:1106
void LockSharedObjectForSession(Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
Definition: lmgr.c:1088
#define AccessExclusiveLock
Definition: lockdefs.h:43
char * pstrdup(const char *in)
Definition: mcxt.c:1624
void pfree(void *pointer)
Definition: mcxt.c:1436
void ForgetDatabaseSyncRequests(Oid dbid)
Definition: md.c:1092
void get_parent_directory(char *path)
Definition: path.c:977
void WaitForProcSignalBarrier(uint64 generation)
Definition: procsignal.c:393
uint64 EmitProcSignalBarrier(ProcSignalBarrierType type)
Definition: procsignal.c:333
@ PROCSIGNAL_BARRIER_SMGRRELEASE
Definition: procsignal.h:53
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:1043
void ResolveRecoveryConflictWithDatabase(Oid dbid)
Definition: standby.c:555
#define stat
Definition: win32_port.h:286
#define S_ISDIR(m)
Definition: win32_port.h:327
#define XLogRecHasAnyBlockRefs(decoder)
Definition: xlogreader.h:416
void XLogDropDatabase(Oid dbid)
Definition: xlogutils.c:669
#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.