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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) 1996-2023, 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/heapam.h"
15 #include "access/htup_details.h"
16 #include "access/tableam.h"
17 #include "access/xact.h"
18 #include "catalog/pg_am.h"
19 #include "catalog/pg_proc.h"
20 #include "commands/defrem.h"
21 #include "miscadmin.h"
22 #include "utils/fmgroids.h"
23 #include "utils/guc_hooks.h"
24 #include "utils/memutils.h"
25 #include "utils/syscache.h"
26 
27 
28 /*
29  * GetTableAmRoutine
30  * Call the specified access method handler routine to get its
31  * TableAmRoutine struct, which will be palloc'd in the caller's
32  * memory context.
33  */
34 const TableAmRoutine *
36 {
37  Datum datum;
38  const TableAmRoutine *routine;
39 
40  datum = OidFunctionCall0(amhandler);
41  routine = (TableAmRoutine *) DatumGetPointer(datum);
42 
43  if (routine == NULL || !IsA(routine, TableAmRoutine))
44  elog(ERROR, "table access method handler %u did not return a TableAmRoutine struct",
45  amhandler);
46 
47  /*
48  * Assert that all required callbacks are present. That makes it a bit
49  * easier to keep AMs up to date, e.g. when forward porting them to a new
50  * major version.
51  */
52  Assert(routine->scan_begin != NULL);
53  Assert(routine->scan_end != NULL);
54  Assert(routine->scan_rescan != NULL);
55  Assert(routine->scan_getnextslot != NULL);
56 
57  Assert(routine->parallelscan_estimate != NULL);
58  Assert(routine->parallelscan_initialize != NULL);
59  Assert(routine->parallelscan_reinitialize != NULL);
60 
61  Assert(routine->index_fetch_begin != NULL);
62  Assert(routine->index_fetch_reset != NULL);
63  Assert(routine->index_fetch_end != NULL);
64  Assert(routine->index_fetch_tuple != NULL);
65 
66  Assert(routine->tuple_fetch_row_version != NULL);
67  Assert(routine->tuple_tid_valid != NULL);
68  Assert(routine->tuple_get_latest_tid != NULL);
69  Assert(routine->tuple_satisfies_snapshot != NULL);
70  Assert(routine->index_delete_tuples != NULL);
71 
72  Assert(routine->tuple_insert != NULL);
73 
74  /*
75  * Could be made optional, but would require throwing error during
76  * parse-analysis.
77  */
78  Assert(routine->tuple_insert_speculative != NULL);
79  Assert(routine->tuple_complete_speculative != NULL);
80 
81  Assert(routine->multi_insert != NULL);
82  Assert(routine->tuple_delete != NULL);
83  Assert(routine->tuple_update != NULL);
84  Assert(routine->tuple_lock != NULL);
85 
86  Assert(routine->relation_set_new_filelocator != NULL);
88  Assert(routine->relation_copy_data != NULL);
89  Assert(routine->relation_copy_for_cluster != NULL);
90  Assert(routine->relation_vacuum != NULL);
91  Assert(routine->scan_analyze_next_block != NULL);
92  Assert(routine->scan_analyze_next_tuple != NULL);
93  Assert(routine->index_build_range_scan != NULL);
94  Assert(routine->index_validate_scan != NULL);
95 
96  Assert(routine->relation_size != NULL);
97  Assert(routine->relation_needs_toast_table != NULL);
98 
99  Assert(routine->relation_estimate_size != NULL);
100 
101  /* optional, but one callback implies presence of the other */
102  Assert((routine->scan_bitmap_next_block == NULL) ==
103  (routine->scan_bitmap_next_tuple == NULL));
104  Assert(routine->scan_sample_next_block != NULL);
105  Assert(routine->scan_sample_next_tuple != NULL);
106 
107  return routine;
108 }
109 
110 /* check_hook: validate new default_table_access_method */
111 bool
113 {
114  if (**newval == '\0')
115  {
116  GUC_check_errdetail("%s cannot be empty.",
117  "default_table_access_method");
118  return false;
119  }
120 
121  if (strlen(*newval) >= NAMEDATALEN)
122  {
123  GUC_check_errdetail("%s is too long (maximum %d characters).",
124  "default_table_access_method", NAMEDATALEN - 1);
125  return false;
126  }
127 
128  /*
129  * If we aren't inside a transaction, or not connected to a database, we
130  * cannot do the catalog access necessary to verify the method. Must
131  * accept the value on faith.
132  */
134  {
135  if (!OidIsValid(get_table_am_oid(*newval, true)))
136  {
137  /*
138  * When source == PGC_S_TEST, don't throw a hard error for a
139  * nonexistent table access method, only a NOTICE. See comments in
140  * guc.h.
141  */
142  if (source == PGC_S_TEST)
143  {
144  ereport(NOTICE,
145  (errcode(ERRCODE_UNDEFINED_OBJECT),
146  errmsg("table access method \"%s\" does not exist",
147  *newval)));
148  }
149  else
150  {
151  GUC_check_errdetail("Table access method \"%s\" does not exist.",
152  *newval);
153  return false;
154  }
155  }
156  }
157 
158  return true;
159 }
Oid get_table_am_oid(const char *amname, bool missing_ok)
Definition: amcmds.c:173
#define OidIsValid(objectId)
Definition: c.h:764
int errcode(int sqlerrcode)
Definition: elog.c:858
int errmsg(const char *fmt,...)
Definition: elog.c:1069
#define ERROR
Definition: elog.h:39
#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:89
#define newval
#define GUC_check_errdetail
Definition: guc.h:445
GucSource
Definition: guc.h:108
@ PGC_S_TEST
Definition: guc.h:121
Assert(fmt[strlen(fmt) - 1] !='\n')
#define IsA(nodeptr, _type_)
Definition: nodes.h:179
#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:392
void(* relation_copy_data)(Relation rel, const RelFileLocator *newrlocator)
Definition: tableam.h:616
bool(* scan_sample_next_tuple)(TableScanDesc scan, struct SampleScanState *scanstate, TupleTableSlot *slot)
Definition: tableam.h:865
void(* index_fetch_reset)(struct IndexFetchTableData *data)
Definition: tableam.h:422
void(* tuple_complete_speculative)(Relation rel, TupleTableSlot *slot, uint32 specToken, bool succeeded)
Definition: tableam.h:516
bool(* scan_bitmap_next_tuple)(TableScanDesc scan, struct TBMIterateResult *tbmres, TupleTableSlot *slot)
Definition: tableam.h:820
void(* parallelscan_reinitialize)(Relation rel, ParallelTableScanDesc pscan)
Definition: tableam.h:399
void(* tuple_get_latest_tid)(TableScanDesc scan, ItemPointer tid)
Definition: tableam.h:481
struct IndexFetchTableData *(* index_fetch_begin)(Relation rel)
Definition: tableam.h:416
bool(* scan_analyze_next_block)(TableScanDesc scan, BlockNumber blockno, BufferAccessStrategy bstrategy)
Definition: tableam.h:667
void(* relation_estimate_size)(Relation rel, int32 *attr_widths, BlockNumber *pages, double *tuples, double *allvisfrac)
Definition: tableam.h:765
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:686
TableScanDesc(* scan_begin)(Relation rel, Snapshot snapshot, int nkeys, struct ScanKeyData *key, ParallelTableScanDesc pscan, uint32 flags)
Definition: tableam.h:320
bool(* relation_needs_toast_table)(Relation rel)
Definition: tableam.h:729
bool(* tuple_tid_valid)(TableScanDesc scan, ItemPointer tid)
Definition: tableam.h:474
void(* multi_insert)(Relation rel, TupleTableSlot **slots, int nslots, CommandId cid, int options, struct BulkInsertStateData *bistate)
Definition: tableam.h:522
void(* scan_end)(TableScanDesc scan)
Definition: tableam.h:330
uint64(* relation_size)(Relation rel, ForkNumber forkNumber)
Definition: tableam.h:719
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:548
bool(* scan_sample_next_block)(TableScanDesc scan, struct SampleScanState *scanstate)
Definition: tableam.h:849
void(* relation_copy_for_cluster)(Relation NewTable, Relation OldTable, 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:620
void(* relation_nontransactional_truncate)(Relation rel)
Definition: tableam.h:608
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:536
void(* tuple_insert)(Relation rel, TupleTableSlot *slot, CommandId cid, int options, struct BulkInsertStateData *bistate)
Definition: tableam.h:503
void(* scan_rescan)(TableScanDesc scan, struct ScanKeyData *key, bool set_params, bool allow_strat, bool allow_sync, bool allow_pagemode)
Definition: tableam.h:336
bool(* tuple_fetch_row_version)(Relation rel, ItemPointer tid, Snapshot snapshot, TupleTableSlot *slot)
Definition: tableam.h:466
void(* relation_vacuum)(Relation rel, struct VacuumParams *params, BufferAccessStrategy bstrategy)
Definition: tableam.h:646
Size(* parallelscan_estimate)(Relation rel)
Definition: tableam.h:385
void(* relation_set_new_filelocator)(Relation rel, const RelFileLocator *newrlocator, char persistence, TransactionId *freezeXid, MultiXactId *minmulti)
Definition: tableam.h:594
bool(* scan_analyze_next_tuple)(TableScanDesc scan, TransactionId OldestXmin, double *liverows, double *deadrows, TupleTableSlot *slot)
Definition: tableam.h:679
TransactionId(* index_delete_tuples)(Relation rel, TM_IndexDeleteOp *delstate)
Definition: tableam.h:493
void(* index_fetch_end)(struct IndexFetchTableData *data)
Definition: tableam.h:427
bool(* index_fetch_tuple)(struct IndexFetchTableData *scan, ItemPointer tid, Snapshot snapshot, TupleTableSlot *slot, bool *call_again, bool *all_dead)
Definition: tableam.h:449
void(* tuple_insert_speculative)(Relation rel, TupleTableSlot *slot, CommandId cid, int options, struct BulkInsertStateData *bistate, uint32 specToken)
Definition: tableam.h:508
TM_Result(* tuple_delete)(Relation rel, ItemPointer tid, CommandId cid, Snapshot snapshot, Snapshot crosscheck, bool wait, TM_FailureData *tmfd, bool changingPart)
Definition: tableam.h:526
bool(* scan_bitmap_next_block)(TableScanDesc scan, struct TBMIterateResult *tbmres)
Definition: tableam.h:806
void(* index_validate_scan)(Relation table_rel, Relation index_rel, struct IndexInfo *index_info, Snapshot snapshot, struct ValidateIndexState *state)
Definition: tableam.h:699
bool(* scan_getnextslot)(TableScanDesc scan, ScanDirection direction, TupleTableSlot *slot)
Definition: tableam.h:343
bool(* tuple_satisfies_snapshot)(Relation rel, TupleTableSlot *slot, Snapshot snapshot)
Definition: tableam.h:488
bool check_default_table_access_method(char **newval, void **extra, GucSource source)
Definition: tableamapi.c:112
const TableAmRoutine * GetTableAmRoutine(Oid amhandler)
Definition: tableamapi.c:35
bool IsTransactionState(void)
Definition: xact.c:378