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
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}
uint8_t uint8
Definition: c.h:486
#define XLOG_DBASE_CREATE_WAL_LOG
#define XLOG_DBASE_DROP
#define XLOG_DBASE_CREATE_FILE_COPY
int i
Definition: isn.c:72
static char * buf
Definition: pg_test_fsync.c:72
void appendStringInfo(StringInfo str, const char *fmt,...)
Definition: stringinfo.c:145
void appendStringInfoString(StringInfo str, const char *s)
Definition: stringinfo.c:230
Oid tablespace_ids[FLEXIBLE_ARRAY_MEMBER]
#define XLogRecGetInfo(decoder)
Definition: xlogreader.h:410
#define XLogRecGetData(decoder)
Definition: xlogreader.h:415

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, and XLogRecGetInfo.

◆ 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}
#define XLR_INFO_MASK
Definition: xlogrecord.h:62

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 3283 of file dbcommands.c.

3284{
3285 uint8 info = XLogRecGetInfo(record) & ~XLR_INFO_MASK;
3286
3287 /* Backup blocks are not used in dbase records */
3289
3290 if (info == XLOG_DBASE_CREATE_FILE_COPY)
3291 {
3294 char *src_path;
3295 char *dst_path;
3296 char *parent_path;
3297 struct stat st;
3298
3299 src_path = GetDatabasePath(xlrec->src_db_id, xlrec->src_tablespace_id);
3300 dst_path = GetDatabasePath(xlrec->db_id, xlrec->tablespace_id);
3301
3302 /*
3303 * Our theory for replaying a CREATE is to forcibly drop the target
3304 * subdirectory if present, then re-copy the source data. This may be
3305 * more work than needed, but it is simple to implement.
3306 */
3307 if (stat(dst_path, &st) == 0 && S_ISDIR(st.st_mode))
3308 {
3309 if (!rmtree(dst_path, true))
3310 /* If this failed, copydir() below is going to error. */
3312 (errmsg("some useless files may be left behind in old database directory \"%s\"",
3313 dst_path)));
3314 }
3315
3316 /*
3317 * If the parent of the target path doesn't exist, create it now. This
3318 * enables us to create the target underneath later.
3319 */
3320 parent_path = pstrdup(dst_path);
3321 get_parent_directory(parent_path);
3322 if (stat(parent_path, &st) < 0)
3323 {
3324 if (errno != ENOENT)
3325 ereport(FATAL,
3326 errmsg("could not stat directory \"%s\": %m",
3327 dst_path));
3328
3329 /* create the parent directory if needed and valid */
3330 recovery_create_dbdir(parent_path, true);
3331 }
3332 pfree(parent_path);
3333
3334 /*
3335 * There's a case where the copy source directory is missing for the
3336 * same reason above. Create the empty source directory so that
3337 * copydir below doesn't fail. The directory will be dropped soon by
3338 * recovery.
3339 */
3340 if (stat(src_path, &st) < 0 && errno == ENOENT)
3341 recovery_create_dbdir(src_path, false);
3342
3343 /*
3344 * Force dirty buffers out to disk, to ensure source database is
3345 * up-to-date for the copy.
3346 */
3348
3349 /* Close all smgr fds in all backends. */
3351
3352 /*
3353 * Copy this subdirectory to the new location
3354 *
3355 * We don't need to copy subdirectories
3356 */
3357 copydir(src_path, dst_path, false);
3358
3359 pfree(src_path);
3360 pfree(dst_path);
3361 }
3362 else if (info == XLOG_DBASE_CREATE_WAL_LOG)
3363 {
3366 char *dbpath;
3367 char *parent_path;
3368
3369 dbpath = GetDatabasePath(xlrec->db_id, xlrec->tablespace_id);
3370
3371 /* create the parent directory if needed and valid */
3372 parent_path = pstrdup(dbpath);
3373 get_parent_directory(parent_path);
3374 recovery_create_dbdir(parent_path, true);
3375
3376 /* Create the database directory with the version file. */
3377 CreateDirAndVersionFile(dbpath, xlrec->db_id, xlrec->tablespace_id,
3378 true);
3379 pfree(dbpath);
3380 }
3381 else if (info == XLOG_DBASE_DROP)
3382 {
3384 char *dst_path;
3385 int i;
3386
3387 if (InHotStandby)
3388 {
3389 /*
3390 * Lock database while we resolve conflicts to ensure that
3391 * InitPostgres() cannot fully re-execute concurrently. This
3392 * avoids backends re-connecting automatically to same database,
3393 * which can happen in some cases.
3394 *
3395 * This will lock out walsenders trying to connect to db-specific
3396 * slots for logical decoding too, so it's safe for us to drop
3397 * slots.
3398 */
3399 LockSharedObjectForSession(DatabaseRelationId, xlrec->db_id, 0, AccessExclusiveLock);
3401 }
3402
3403 /* Drop any database-specific replication slots */
3405
3406 /* Drop pages for this database that are in the shared buffer cache */
3407 DropDatabaseBuffers(xlrec->db_id);
3408
3409 /* Also, clean out any fsync requests that might be pending in md.c */
3411
3412 /* Clean out the xlog relcache too */
3413 XLogDropDatabase(xlrec->db_id);
3414
3415 /* Close all smgr fds in all backends. */
3417
3418 for (i = 0; i < xlrec->ntablespaces; i++)
3419 {
3420 dst_path = GetDatabasePath(xlrec->db_id, xlrec->tablespace_ids[i]);
3421
3422 /* And remove the physical files */
3423 if (!rmtree(dst_path, true))
3425 (errmsg("some useless files may be left behind in old database directory \"%s\"",
3426 dst_path)));
3427 pfree(dst_path);
3428 }
3429
3430 if (InHotStandby)
3431 {
3432 /*
3433 * Release locks prior to commit. XXX There is a race condition
3434 * here that may allow backends to reconnect, but the window for
3435 * this is small because the gap between here and commit is mostly
3436 * fairly small and it is unlikely that people will be dropping
3437 * databases that we are trying to connect to anyway.
3438 */
3439 UnlockSharedObjectForSession(DatabaseRelationId, xlrec->db_id, 0, AccessExclusiveLock);
3440 }
3441 }
3442 else
3443 elog(PANIC, "dbase_redo: unknown op code %u", info);
3444}
void DropDatabaseBuffers(Oid dbid)
Definition: bufmgr.c:4386
void FlushDatabaseBuffers(Oid dbid)
Definition: bufmgr.c:4804
#define Assert(condition)
Definition: c.h:815
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:3254
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:225
#define ereport(elevel,...)
Definition: elog.h:149
void UnlockSharedObjectForSession(Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
Definition: lmgr.c:1170
void LockSharedObjectForSession(Oid classid, Oid objid, uint16 objsubid, LOCKMODE lockmode)
Definition: lmgr.c:1152
#define AccessExclusiveLock
Definition: lockdefs.h:43
char * pstrdup(const char *in)
Definition: mcxt.c:1696
void pfree(void *pointer)
Definition: mcxt.c:1521
void ForgetDatabaseSyncRequests(Oid dbid)
Definition: md.c:1443
void get_parent_directory(char *path)
Definition: path.c:1068
void WaitForProcSignalBarrier(uint64 generation)
Definition: procsignal.c:421
uint64 EmitProcSignalBarrier(ProcSignalBarrierType type)
Definition: procsignal.c:353
@ 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:1302
void ResolveRecoveryConflictWithDatabase(Oid dbid)
Definition: standby.c:568
#define stat
Definition: win32_port.h:274
#define S_ISDIR(m)
Definition: win32_port.h:315
#define XLogRecHasAnyBlockRefs(decoder)
Definition: xlogreader.h:417
void XLogDropDatabase(Oid dbid)
Definition: xlogutils.c:652
#define InHotStandby
Definition: xlogutils.h:60

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, and XLogRecHasAnyBlockRefs.