1 /*-------------------------------------------------------------------------
2  *
3  * heapam.h
4  *	  POSTGRES heap access method definitions.
5  *
6  *
7  * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
8  * Portions Copyright (c) 1994, Regents of the University of California
9  *
10  * src/include/access/heapam.h
11  *
12  *-------------------------------------------------------------------------
13  */
14 #ifndef HEAPAM_H
15 #define HEAPAM_H
16 
17 #include "access/relation.h"	/* for backward compatibility */
18 #include "access/relscan.h"
19 #include "access/sdir.h"
20 #include "access/skey.h"
21 #include "access/table.h"		/* for backward compatibility */
22 #include "access/tableam.h"
23 #include "nodes/lockoptions.h"
24 #include "nodes/primnodes.h"
25 #include "storage/bufpage.h"
26 #include "storage/dsm.h"
27 #include "storage/lockdefs.h"
28 #include "storage/shm_toc.h"
29 #include "utils/relcache.h"
30 #include "utils/snapshot.h"
31 
32 
33 /* "options" flag bits for heap_insert */
34 #define HEAP_INSERT_SKIP_FSM	TABLE_INSERT_SKIP_FSM
35 #define HEAP_INSERT_FROZEN		TABLE_INSERT_FROZEN
36 #define HEAP_INSERT_NO_LOGICAL	TABLE_INSERT_NO_LOGICAL
37 #define HEAP_INSERT_SPECULATIVE 0x0010
38 
39 typedef struct BulkInsertStateData *BulkInsertState;
40 struct TupleTableSlot;
41 
42 #define MaxLockTupleMode	LockTupleExclusive
43 
44 /*
45  * Descriptor for heap table scans.
46  */
47 typedef struct HeapScanDescData
48 {
49 	TableScanDescData rs_base;	/* AM independent part of the descriptor */
50 
51 	/* state set up at initscan time */
52 	BlockNumber rs_nblocks;		/* total number of blocks in rel */
53 	BlockNumber rs_startblock;	/* block # to start at */
54 	BlockNumber rs_numblocks;	/* max number of blocks to scan */
55 	/* rs_numblocks is usually InvalidBlockNumber, meaning "scan whole rel" */
56 
57 	/* scan current state */
58 	bool		rs_inited;		/* false = scan not init'd yet */
59 	BlockNumber rs_cblock;		/* current block # in scan, if any */
60 	Buffer		rs_cbuf;		/* current buffer in scan, if any */
61 	/* NB: if rs_cbuf is not InvalidBuffer, we hold a pin on that buffer */
62 
63 	/* rs_numblocks is usually InvalidBlockNumber, meaning "scan whole rel" */
64 	BufferAccessStrategy rs_strategy;	/* access strategy for reads */
65 
66 	HeapTupleData rs_ctup;		/* current tuple in scan, if any */
67 
68 	/*
69 	 * For parallel scans to store page allocation data.  NULL when not
70 	 * performing a parallel scan.
71 	 */
72 	ParallelBlockTableScanWorkerData *rs_parallelworkerdata;
73 
74 	/* these fields only used in page-at-a-time mode and for bitmap scans */
75 	int			rs_cindex;		/* current tuple's index in vistuples */
76 	int			rs_ntuples;		/* number of visible tuples on page */
77 	OffsetNumber rs_vistuples[MaxHeapTuplesPerPage];	/* their offsets */
78 }			HeapScanDescData;
79 typedef struct HeapScanDescData *HeapScanDesc;
80 
81 /*
82  * Descriptor for fetches from heap via an index.
83  */
84 typedef struct IndexFetchHeapData
85 {
86 	IndexFetchTableData xs_base;	/* AM independent part of the descriptor */
87 
88 	Buffer		xs_cbuf;		/* current heap buffer in scan, if any */
89 	/* NB: if xs_cbuf is not InvalidBuffer, we hold a pin on that buffer */
90 } IndexFetchHeapData;
91 
92 /* Result codes for HeapTupleSatisfiesVacuum */
93 typedef enum
94 {
95 	HEAPTUPLE_DEAD,				/* tuple is dead and deletable */
96 	HEAPTUPLE_LIVE,				/* tuple is live (committed, no deleter) */
97 	HEAPTUPLE_RECENTLY_DEAD,	/* tuple is dead, but not deletable yet */
98 	HEAPTUPLE_INSERT_IN_PROGRESS,	/* inserting xact is still in progress */
99 	HEAPTUPLE_DELETE_IN_PROGRESS	/* deleting xact is still in progress */
100 } HTSV_Result;
101 
102 /* ----------------
103  *		function prototypes for heap access method
104  *
105  * heap_create, heap_create_with_catalog, and heap_drop_with_catalog
106  * are declared in catalog/heap.h
107  * ----------------
108  */
109 
110 
111 /*
112  * HeapScanIsValid
113  *		True iff the heap scan is valid.
114  */
115 #define HeapScanIsValid(scan) PointerIsValid(scan)
116 
117 extern TableScanDesc heap_beginscan(Relation relation, Snapshot snapshot,
118 									int nkeys, ScanKey key,
119 									ParallelTableScanDesc parallel_scan,
120 									uint32 flags);
121 extern void heap_setscanlimits(TableScanDesc scan, BlockNumber startBlk,
122 							   BlockNumber numBlks);
123 extern void heapgetpage(TableScanDesc scan, BlockNumber page);
124 extern void heap_rescan(TableScanDesc scan, ScanKey key, bool set_params,
125 						bool allow_strat, bool allow_sync, bool allow_pagemode);
126 extern void heap_endscan(TableScanDesc scan);
127 extern HeapTuple heap_getnext(TableScanDesc scan, ScanDirection direction);
128 extern bool heap_getnextslot(TableScanDesc sscan,
129 							 ScanDirection direction, struct TupleTableSlot *slot);
130 extern void heap_set_tidrange(TableScanDesc sscan, ItemPointer mintid,
131 							  ItemPointer maxtid);
132 extern bool heap_getnextslot_tidrange(TableScanDesc sscan,
133 									  ScanDirection direction,
134 									  TupleTableSlot *slot);
135 extern bool heap_fetch(Relation relation, Snapshot snapshot,
136 					   HeapTuple tuple, Buffer *userbuf);
137 extern bool heap_hot_search_buffer(ItemPointer tid, Relation relation,
138 								   Buffer buffer, Snapshot snapshot, HeapTuple heapTuple,
139 								   bool *all_dead, bool first_call);
140 
141 extern void heap_get_latest_tid(TableScanDesc scan, ItemPointer tid);
142 
143 extern BulkInsertState GetBulkInsertState(void);
144 extern void FreeBulkInsertState(BulkInsertState);
145 extern void ReleaseBulkInsertStatePin(BulkInsertState bistate);
146 
147 extern void heap_insert(Relation relation, HeapTuple tup, CommandId cid,
148 						int options, BulkInsertState bistate);
149 extern void heap_multi_insert(Relation relation, struct TupleTableSlot **slots,
150 							  int ntuples, CommandId cid, int options,
151 							  BulkInsertState bistate);
152 extern TM_Result heap_delete(Relation relation, ItemPointer tid,
153 							 CommandId cid, Snapshot crosscheck, bool wait,
154 							 struct TM_FailureData *tmfd, bool changingPart);
155 extern void heap_finish_speculative(Relation relation, ItemPointer tid);
156 extern void heap_abort_speculative(Relation relation, ItemPointer tid);
157 extern TM_Result heap_update(Relation relation, ItemPointer otid,
158 							 HeapTuple newtup,
159 							 CommandId cid, Snapshot crosscheck, bool wait,
160 							 struct TM_FailureData *tmfd, LockTupleMode *lockmode);
161 extern TM_Result heap_lock_tuple(Relation relation, HeapTuple tuple,
162 								 CommandId cid, LockTupleMode mode, LockWaitPolicy wait_policy,
163 								 bool follow_update,
164 								 Buffer *buffer, struct TM_FailureData *tmfd);
165 
166 extern void heap_inplace_update(Relation relation, HeapTuple tuple);
167 extern bool heap_freeze_tuple(HeapTupleHeader tuple,
168 							  TransactionId relfrozenxid, TransactionId relminmxid,
169 							  TransactionId cutoff_xid, TransactionId cutoff_multi);
170 extern bool heap_tuple_needs_freeze(HeapTupleHeader tuple, TransactionId cutoff_xid,
171 									MultiXactId cutoff_multi, Buffer buf);
172 extern bool heap_tuple_needs_eventual_freeze(HeapTupleHeader tuple);
173 
174 extern void simple_heap_insert(Relation relation, HeapTuple tup);
175 extern void simple_heap_delete(Relation relation, ItemPointer tid);
176 extern void simple_heap_update(Relation relation, ItemPointer otid,
177 							   HeapTuple tup);
178 
179 extern TransactionId heap_index_delete_tuples(Relation rel,
180 											  TM_IndexDeleteOp *delstate);
181 
182 /* in heap/pruneheap.c */
183 struct GlobalVisState;
184 extern void heap_page_prune_opt(Relation relation, Buffer buffer);
185 extern int	heap_page_prune(Relation relation, Buffer buffer,
186 							struct GlobalVisState *vistest,
187 							TransactionId old_snap_xmin,
188 							TimestampTz old_snap_ts_ts,
189 							bool report_stats,
190 							OffsetNumber *off_loc);
191 extern void heap_page_prune_execute(Buffer buffer,
192 									OffsetNumber *redirected, int nredirected,
193 									OffsetNumber *nowdead, int ndead,
194 									OffsetNumber *nowunused, int nunused);
195 extern void heap_get_root_tuples(Page page, OffsetNumber *root_offsets);
196 
197 /* in heap/vacuumlazy.c */
198 struct VacuumParams;
199 extern void heap_vacuum_rel(Relation rel,
200 							struct VacuumParams *params, BufferAccessStrategy bstrategy);
201 extern void parallel_vacuum_main(dsm_segment *seg, shm_toc *toc);
202 
203 /* in heap/heapam_visibility.c */
204 extern bool HeapTupleSatisfiesVisibility(HeapTuple stup, Snapshot snapshot,
205 										 Buffer buffer);
206 extern TM_Result HeapTupleSatisfiesUpdate(HeapTuple stup, CommandId curcid,
207 										  Buffer buffer);
208 extern HTSV_Result HeapTupleSatisfiesVacuum(HeapTuple stup, TransactionId OldestXmin,
209 											Buffer buffer);
210 extern HTSV_Result HeapTupleSatisfiesVacuumHorizon(HeapTuple stup, Buffer buffer,
211 												   TransactionId *dead_after);
212 extern void HeapTupleSetHintBits(HeapTupleHeader tuple, Buffer buffer,
213 								 uint16 infomask, TransactionId xid);
214 extern bool HeapTupleHeaderIsOnlyLocked(HeapTupleHeader tuple);
215 extern bool XidInMVCCSnapshot(TransactionId xid, Snapshot snapshot);
216 extern bool HeapTupleIsSurelyDead(HeapTuple htup,
217 								  struct GlobalVisState *vistest);
218 
219 /*
220  * To avoid leaking too much knowledge about reorderbuffer implementation
221  * details this is implemented in reorderbuffer.c not heapam_visibility.c
222  */
223 struct HTAB;
224 extern bool ResolveCminCmaxDuringDecoding(struct HTAB *tuplecid_data,
225 										  Snapshot snapshot,
226 										  HeapTuple htup,
227 										  Buffer buffer,
228 										  CommandId *cmin, CommandId *cmax);
229 extern void HeapCheckForSerializableConflictOut(bool valid, Relation relation, HeapTuple tuple,
230 												Buffer buffer, Snapshot snapshot);
231 
232 #endif							/* HEAPAM_H */
233