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tableamapi.c
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1 /*----------------------------------------------------------------------
2  *
3  * tableamapi.c
4  * Support routines for API for Postgres table access methods
5  *
6  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  * src/backend/access/table/tableamapi.c
10  *----------------------------------------------------------------------
11  */
12 #include "postgres.h"
13 
14 #include "access/tableam.h"
15 #include "access/xact.h"
16 #include "commands/defrem.h"
17 #include "miscadmin.h"
18 #include "utils/guc_hooks.h"
19 
20 
21 /*
22  * GetTableAmRoutine
23  * Call the specified access method handler routine to get its
24  * TableAmRoutine struct, which will be palloc'd in the caller's
25  * memory context.
26  */
27 const TableAmRoutine *
29 {
30  Datum datum;
31  const TableAmRoutine *routine;
32 
33  datum = OidFunctionCall0(amhandler);
34  routine = (TableAmRoutine *) DatumGetPointer(datum);
35 
36  if (routine == NULL || !IsA(routine, TableAmRoutine))
37  elog(ERROR, "table access method handler %u did not return a TableAmRoutine struct",
38  amhandler);
39 
40  /*
41  * Assert that all required callbacks are present. That makes it a bit
42  * easier to keep AMs up to date, e.g. when forward porting them to a new
43  * major version.
44  */
45  Assert(routine->scan_begin != NULL);
46  Assert(routine->scan_end != NULL);
47  Assert(routine->scan_rescan != NULL);
48  Assert(routine->scan_getnextslot != NULL);
49 
50  Assert(routine->parallelscan_estimate != NULL);
51  Assert(routine->parallelscan_initialize != NULL);
52  Assert(routine->parallelscan_reinitialize != NULL);
53 
54  Assert(routine->index_fetch_begin != NULL);
55  Assert(routine->index_fetch_reset != NULL);
56  Assert(routine->index_fetch_end != NULL);
57  Assert(routine->index_fetch_tuple != NULL);
58 
59  Assert(routine->tuple_fetch_row_version != NULL);
60  Assert(routine->tuple_tid_valid != NULL);
61  Assert(routine->tuple_get_latest_tid != NULL);
62  Assert(routine->tuple_satisfies_snapshot != NULL);
63  Assert(routine->index_delete_tuples != NULL);
64 
65  Assert(routine->tuple_insert != NULL);
66 
67  /*
68  * Could be made optional, but would require throwing error during
69  * parse-analysis.
70  */
71  Assert(routine->tuple_insert_speculative != NULL);
72  Assert(routine->tuple_complete_speculative != NULL);
73 
74  Assert(routine->multi_insert != NULL);
75  Assert(routine->tuple_delete != NULL);
76  Assert(routine->tuple_update != NULL);
77  Assert(routine->tuple_lock != NULL);
78 
79  Assert(routine->relation_set_new_filelocator != NULL);
81  Assert(routine->relation_copy_data != NULL);
82  Assert(routine->relation_copy_for_cluster != NULL);
83  Assert(routine->relation_vacuum != NULL);
84  Assert(routine->scan_analyze_next_block != NULL);
85  Assert(routine->scan_analyze_next_tuple != NULL);
86  Assert(routine->index_build_range_scan != NULL);
87  Assert(routine->index_validate_scan != NULL);
88 
89  Assert(routine->relation_size != NULL);
90  Assert(routine->relation_needs_toast_table != NULL);
91 
92  Assert(routine->relation_estimate_size != NULL);
93 
94  /* optional, but one callback implies presence of the other */
95  Assert((routine->scan_bitmap_next_block == NULL) ==
96  (routine->scan_bitmap_next_tuple == NULL));
97  Assert(routine->scan_sample_next_block != NULL);
98  Assert(routine->scan_sample_next_tuple != NULL);
99 
100  return routine;
101 }
102 
103 /* check_hook: validate new default_table_access_method */
104 bool
106 {
107  if (**newval == '\0')
108  {
109  GUC_check_errdetail("\"%s\" cannot be empty.",
110  "default_table_access_method");
111  return false;
112  }
113 
114  if (strlen(*newval) >= NAMEDATALEN)
115  {
116  GUC_check_errdetail("\"%s\" is too long (maximum %d characters).",
117  "default_table_access_method", NAMEDATALEN - 1);
118  return false;
119  }
120 
121  /*
122  * If we aren't inside a transaction, or not connected to a database, we
123  * cannot do the catalog access necessary to verify the method. Must
124  * accept the value on faith.
125  */
127  {
128  if (!OidIsValid(get_table_am_oid(*newval, true)))
129  {
130  /*
131  * When source == PGC_S_TEST, don't throw a hard error for a
132  * nonexistent table access method, only a NOTICE. See comments in
133  * guc.h.
134  */
135  if (source == PGC_S_TEST)
136  {
137  ereport(NOTICE,
138  (errcode(ERRCODE_UNDEFINED_OBJECT),
139  errmsg("table access method \"%s\" does not exist",
140  *newval)));
141  }
142  else
143  {
144  GUC_check_errdetail("Table access method \"%s\" does not exist.",
145  *newval);
146  return false;
147  }
148  }
149  }
150 
151  return true;
152 }
Oid get_table_am_oid(const char *amname, bool missing_ok)
Definition: amcmds.c:173
#define Assert(condition)
Definition: c.h:858
#define OidIsValid(objectId)
Definition: c.h:775
int errcode(int sqlerrcode)
Definition: elog.c:857
int errmsg(const char *fmt,...)
Definition: elog.c:1070
#define ERROR
Definition: elog.h:39
#define elog(elevel,...)
Definition: elog.h:224
#define NOTICE
Definition: elog.h:35
#define ereport(elevel,...)
Definition: elog.h:149
#define OidFunctionCall0(functionId)
Definition: fmgr.h:678
Oid MyDatabaseId
Definition: globals.c:91
#define newval
#define GUC_check_errdetail
Definition: guc.h:447
GucSource
Definition: guc.h:108
@ PGC_S_TEST
Definition: guc.h:121
#define IsA(nodeptr, _type_)
Definition: nodes.h:158
#define NAMEDATALEN
static rewind_source * source
Definition: pg_rewind.c:89
uintptr_t Datum
Definition: postgres.h:64
static Pointer DatumGetPointer(Datum X)
Definition: postgres.h:312
#define InvalidOid
Definition: postgres_ext.h:36
unsigned int Oid
Definition: postgres_ext.h:31
Size(* parallelscan_initialize)(Relation rel, ParallelTableScanDesc pscan)
Definition: tableam.h:400
void(* relation_copy_data)(Relation rel, const RelFileLocator *newrlocator)
Definition: tableam.h:624
bool(* scan_sample_next_tuple)(TableScanDesc scan, struct SampleScanState *scanstate, TupleTableSlot *slot)
Definition: tableam.h:882
void(* index_fetch_reset)(struct IndexFetchTableData *data)
Definition: tableam.h:430
void(* tuple_complete_speculative)(Relation rel, TupleTableSlot *slot, uint32 specToken, bool succeeded)
Definition: tableam.h:524
bool(* scan_bitmap_next_tuple)(TableScanDesc scan, struct TBMIterateResult *tbmres, TupleTableSlot *slot)
Definition: tableam.h:837
void(* parallelscan_reinitialize)(Relation rel, ParallelTableScanDesc pscan)
Definition: tableam.h:407
void(* tuple_get_latest_tid)(TableScanDesc scan, ItemPointer tid)
Definition: tableam.h:489
struct IndexFetchTableData *(* index_fetch_begin)(Relation rel)
Definition: tableam.h:424
void(* relation_copy_for_cluster)(Relation OldTable, Relation NewTable, Relation OldIndex, bool use_sort, TransactionId OldestXmin, TransactionId *xid_cutoff, MultiXactId *multi_cutoff, double *num_tuples, double *tups_vacuumed, double *tups_recently_dead)
Definition: tableam.h:628
void(* relation_estimate_size)(Relation rel, int32 *attr_widths, BlockNumber *pages, double *tuples, double *allvisfrac)
Definition: tableam.h:782
double(* index_build_range_scan)(Relation table_rel, Relation index_rel, struct IndexInfo *index_info, bool allow_sync, bool anyvisible, bool progress, BlockNumber start_blockno, BlockNumber numblocks, IndexBuildCallback callback, void *callback_state, TableScanDesc scan)
Definition: tableam.h:703
TableScanDesc(* scan_begin)(Relation rel, Snapshot snapshot, int nkeys, struct ScanKeyData *key, ParallelTableScanDesc pscan, uint32 flags)
Definition: tableam.h:328
bool(* relation_needs_toast_table)(Relation rel)
Definition: tableam.h:746
bool(* tuple_tid_valid)(TableScanDesc scan, ItemPointer tid)
Definition: tableam.h:482
void(* multi_insert)(Relation rel, TupleTableSlot **slots, int nslots, CommandId cid, int options, struct BulkInsertStateData *bistate)
Definition: tableam.h:530
void(* scan_end)(TableScanDesc scan)
Definition: tableam.h:338
uint64(* relation_size)(Relation rel, ForkNumber forkNumber)
Definition: tableam.h:736
TM_Result(* tuple_lock)(Relation rel, ItemPointer tid, Snapshot snapshot, TupleTableSlot *slot, CommandId cid, LockTupleMode mode, LockWaitPolicy wait_policy, uint8 flags, TM_FailureData *tmfd)
Definition: tableam.h:556
bool(* scan_sample_next_block)(TableScanDesc scan, struct SampleScanState *scanstate)
Definition: tableam.h:866
void(* relation_nontransactional_truncate)(Relation rel)
Definition: tableam.h:616
TM_Result(* tuple_update)(Relation rel, ItemPointer otid, TupleTableSlot *slot, CommandId cid, Snapshot snapshot, Snapshot crosscheck, bool wait, TM_FailureData *tmfd, LockTupleMode *lockmode, TU_UpdateIndexes *update_indexes)
Definition: tableam.h:544
void(* tuple_insert)(Relation rel, TupleTableSlot *slot, CommandId cid, int options, struct BulkInsertStateData *bistate)
Definition: tableam.h:511
void(* scan_rescan)(TableScanDesc scan, struct ScanKeyData *key, bool set_params, bool allow_strat, bool allow_sync, bool allow_pagemode)
Definition: tableam.h:344
bool(* tuple_fetch_row_version)(Relation rel, ItemPointer tid, Snapshot snapshot, TupleTableSlot *slot)
Definition: tableam.h:474
void(* relation_vacuum)(Relation rel, struct VacuumParams *params, BufferAccessStrategy bstrategy)
Definition: tableam.h:654
bool(* scan_analyze_next_block)(TableScanDesc scan, ReadStream *stream)
Definition: tableam.h:685
Size(* parallelscan_estimate)(Relation rel)
Definition: tableam.h:393
void(* relation_set_new_filelocator)(Relation rel, const RelFileLocator *newrlocator, char persistence, TransactionId *freezeXid, MultiXactId *minmulti)
Definition: tableam.h:602
bool(* scan_analyze_next_tuple)(TableScanDesc scan, TransactionId OldestXmin, double *liverows, double *deadrows, TupleTableSlot *slot)
Definition: tableam.h:696
TransactionId(* index_delete_tuples)(Relation rel, TM_IndexDeleteOp *delstate)
Definition: tableam.h:501
void(* index_fetch_end)(struct IndexFetchTableData *data)
Definition: tableam.h:435
bool(* index_fetch_tuple)(struct IndexFetchTableData *scan, ItemPointer tid, Snapshot snapshot, TupleTableSlot *slot, bool *call_again, bool *all_dead)
Definition: tableam.h:457
void(* tuple_insert_speculative)(Relation rel, TupleTableSlot *slot, CommandId cid, int options, struct BulkInsertStateData *bistate, uint32 specToken)
Definition: tableam.h:516
TM_Result(* tuple_delete)(Relation rel, ItemPointer tid, CommandId cid, Snapshot snapshot, Snapshot crosscheck, bool wait, TM_FailureData *tmfd, bool changingPart)
Definition: tableam.h:534
bool(* scan_bitmap_next_block)(TableScanDesc scan, struct TBMIterateResult *tbmres)
Definition: tableam.h:823
void(* index_validate_scan)(Relation table_rel, Relation index_rel, struct IndexInfo *index_info, Snapshot snapshot, struct ValidateIndexState *state)
Definition: tableam.h:716
bool(* scan_getnextslot)(TableScanDesc scan, ScanDirection direction, TupleTableSlot *slot)
Definition: tableam.h:351
bool(* tuple_satisfies_snapshot)(Relation rel, TupleTableSlot *slot, Snapshot snapshot)
Definition: tableam.h:496
bool check_default_table_access_method(char **newval, void **extra, GucSource source)
Definition: tableamapi.c:105
const TableAmRoutine * GetTableAmRoutine(Oid amhandler)
Definition: tableamapi.c:28
bool IsTransactionState(void)
Definition: xact.c:384