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typcache.h
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1 /*-------------------------------------------------------------------------
2  *
3  * typcache.h
4  * Type cache definitions.
5  *
6  * The type cache exists to speed lookup of certain information about data
7  * types that is not directly available from a type's pg_type row.
8  *
9  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
10  * Portions Copyright (c) 1994, Regents of the University of California
11  *
12  * src/include/utils/typcache.h
13  *
14  *-------------------------------------------------------------------------
15  */
16 #ifndef TYPCACHE_H
17 #define TYPCACHE_H
18 
19 #include "access/tupdesc.h"
20 #include "fmgr.h"
21 #include "storage/dsm.h"
22 #include "utils/dsa.h"
23 
24 
25 /* DomainConstraintCache is an opaque struct known only within typcache.c */
27 
28 /* TypeCacheEnumData is an opaque struct known only within typcache.c */
29 struct TypeCacheEnumData;
30 
31 typedef struct TypeCacheEntry
32 {
33  /* typeId is the hash lookup key and MUST BE FIRST */
34  Oid type_id; /* OID of the data type */
35 
36  uint32 type_id_hash; /* hashed value of the OID */
37 
38  /* some subsidiary information copied from the pg_type row */
40  bool typbyval;
41  char typalign;
42  char typstorage;
43  char typtype;
48 
49  /*
50  * Information obtained from opfamily entries
51  *
52  * These will be InvalidOid if no match could be found, or if the
53  * information hasn't yet been requested. Also note that for array and
54  * composite types, typcache.c checks that the contained types are
55  * comparable or hashable before allowing eq_opr etc to become set.
56  */
57  Oid btree_opf; /* the default btree opclass' family */
58  Oid btree_opintype; /* the default btree opclass' opcintype */
59  Oid hash_opf; /* the default hash opclass' family */
60  Oid hash_opintype; /* the default hash opclass' opcintype */
61  Oid eq_opr; /* the equality operator */
62  Oid lt_opr; /* the less-than operator */
63  Oid gt_opr; /* the greater-than operator */
64  Oid cmp_proc; /* the btree comparison function */
65  Oid hash_proc; /* the hash calculation function */
66  Oid hash_extended_proc; /* the extended hash calculation function */
67 
68  /*
69  * Pre-set-up fmgr call info for the equality operator, the btree
70  * comparison function, and the hash calculation function. These are kept
71  * in the type cache to avoid problems with memory leaks in repeated calls
72  * to functions such as array_eq, array_cmp, hash_array. There is not
73  * currently a need to maintain call info for the lt_opr or gt_opr.
74  */
79 
80  /*
81  * Tuple descriptor if it's a composite type (row type). NULL if not
82  * composite or information hasn't yet been requested. (NOTE: this is a
83  * reference-counted tupledesc.)
84  *
85  * To simplify caching dependent info, tupDesc_identifier is an identifier
86  * for this tupledesc that is unique for the life of the process, and
87  * changes anytime the tupledesc does. Zero if not yet determined.
88  */
91 
92  /*
93  * Fields computed when TYPECACHE_RANGE_INFO is requested. Zeroes if not
94  * a range type or information hasn't yet been requested. Note that
95  * rng_cmp_proc_finfo could be different from the element type's default
96  * btree comparison function.
97  */
98  struct TypeCacheEntry *rngelemtype; /* range's element type */
99  Oid rng_opfamily; /* opfamily to use for range comparisons */
100  Oid rng_collation; /* collation for comparisons, if any */
101  FmgrInfo rng_cmp_proc_finfo; /* comparison function */
102  FmgrInfo rng_canonical_finfo; /* canonicalization function, if any */
103  FmgrInfo rng_subdiff_finfo; /* difference function, if any */
104 
105  /*
106  * Fields computed when TYPECACHE_MULTIRANGE_INFO is required.
107  */
108  struct TypeCacheEntry *rngtype; /* multirange's range underlying type */
109 
110  /*
111  * Domain's base type and typmod if it's a domain type. Zeroes if not
112  * domain, or if information hasn't been requested.
113  */
116 
117  /*
118  * Domain constraint data if it's a domain type. NULL if not domain, or
119  * if domain has no constraints, or if information hasn't been requested.
120  */
122 
123  /* Private data, for internal use of typcache.c only */
124  int flags; /* flags about what we've computed */
125 
126  /*
127  * Private information about an enum type. NULL if not enum or
128  * information hasn't been requested.
129  */
131 
132  /* We also maintain a list of all known domain-type cache entries */
135 
136 /* Bit flags to indicate which fields a given caller needs to have set */
137 #define TYPECACHE_EQ_OPR 0x00001
138 #define TYPECACHE_LT_OPR 0x00002
139 #define TYPECACHE_GT_OPR 0x00004
140 #define TYPECACHE_CMP_PROC 0x00008
141 #define TYPECACHE_HASH_PROC 0x00010
142 #define TYPECACHE_EQ_OPR_FINFO 0x00020
143 #define TYPECACHE_CMP_PROC_FINFO 0x00040
144 #define TYPECACHE_HASH_PROC_FINFO 0x00080
145 #define TYPECACHE_TUPDESC 0x00100
146 #define TYPECACHE_BTREE_OPFAMILY 0x00200
147 #define TYPECACHE_HASH_OPFAMILY 0x00400
148 #define TYPECACHE_RANGE_INFO 0x00800
149 #define TYPECACHE_DOMAIN_BASE_INFO 0x01000
150 #define TYPECACHE_DOMAIN_CONSTR_INFO 0x02000
151 #define TYPECACHE_HASH_EXTENDED_PROC 0x04000
152 #define TYPECACHE_HASH_EXTENDED_PROC_FINFO 0x08000
153 #define TYPECACHE_MULTIRANGE_INFO 0x10000
154 
155 /* This value will not equal any valid tupledesc identifier, nor 0 */
156 #define INVALID_TUPLEDESC_IDENTIFIER ((uint64) 1)
157 
158 /*
159  * Callers wishing to maintain a long-lived reference to a domain's constraint
160  * set must store it in one of these. Use InitDomainConstraintRef() and
161  * UpdateDomainConstraintRef() to manage it. Note: DomainConstraintState is
162  * considered an executable expression type, so it's defined in execnodes.h.
163  */
164 typedef struct DomainConstraintRef
165 {
166  List *constraints; /* list of DomainConstraintState nodes */
167  MemoryContext refctx; /* context holding DomainConstraintRef */
168  TypeCacheEntry *tcache; /* typcache entry for domain type */
169  bool need_exprstate; /* does caller need check_exprstate? */
170 
171  /* Management data --- treat these fields as private to typcache.c */
172  DomainConstraintCache *dcc; /* current constraints, or NULL if none */
173  MemoryContextCallback callback; /* used to release refcount when done */
175 
177 
178 extern TypeCacheEntry *lookup_type_cache(Oid type_id, int flags);
179 
180 extern void InitDomainConstraintRef(Oid type_id, DomainConstraintRef *ref,
181  MemoryContext refctx, bool need_exprstate);
182 
184 
185 extern bool DomainHasConstraints(Oid type_id);
186 
187 extern TupleDesc lookup_rowtype_tupdesc(Oid type_id, int32 typmod);
188 
189 extern TupleDesc lookup_rowtype_tupdesc_noerror(Oid type_id, int32 typmod,
190  bool noError);
191 
192 extern TupleDesc lookup_rowtype_tupdesc_copy(Oid type_id, int32 typmod);
193 
194 extern TupleDesc lookup_rowtype_tupdesc_domain(Oid type_id, int32 typmod,
195  bool noError);
196 
197 extern void assign_record_type_typmod(TupleDesc tupDesc);
198 
199 extern uint64 assign_record_type_identifier(Oid type_id, int32 typmod);
200 
201 extern int compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2);
202 
203 extern size_t SharedRecordTypmodRegistryEstimate(void);
204 
206  dsm_segment *segment, dsa_area *area);
207 
209 
210 #endif /* TYPCACHE_H */
unsigned int uint32
Definition: c.h:493
signed short int16
Definition: c.h:480
signed int int32
Definition: c.h:481
unsigned int Oid
Definition: postgres_ext.h:31
DomainConstraintCache * dcc
Definition: typcache.h:172
MemoryContext refctx
Definition: typcache.h:167
MemoryContextCallback callback
Definition: typcache.h:173
TypeCacheEntry * tcache
Definition: typcache.h:168
Definition: fmgr.h:57
Definition: pg_list.h:54
uint32 type_id_hash
Definition: typcache.h:36
uint64 tupDesc_identifier
Definition: typcache.h:90
FmgrInfo hash_proc_finfo
Definition: typcache.h:77
int32 domainBaseTypmod
Definition: typcache.h:115
Oid hash_extended_proc
Definition: typcache.h:66
Oid typsubscript
Definition: typcache.h:45
FmgrInfo rng_cmp_proc_finfo
Definition: typcache.h:101
FmgrInfo cmp_proc_finfo
Definition: typcache.h:76
Oid rng_collation
Definition: typcache.h:100
char typalign
Definition: typcache.h:41
struct TypeCacheEntry * rngelemtype
Definition: typcache.h:98
char typtype
Definition: typcache.h:43
TupleDesc tupDesc
Definition: typcache.h:89
FmgrInfo hash_extended_proc_finfo
Definition: typcache.h:78
DomainConstraintCache * domainData
Definition: typcache.h:121
struct TypeCacheEntry * rngtype
Definition: typcache.h:108
FmgrInfo rng_subdiff_finfo
Definition: typcache.h:103
FmgrInfo eq_opr_finfo
Definition: typcache.h:75
Oid btree_opintype
Definition: typcache.h:58
struct TypeCacheEnumData * enumData
Definition: typcache.h:130
struct TypeCacheEntry * nextDomain
Definition: typcache.h:133
bool typbyval
Definition: typcache.h:40
FmgrInfo rng_canonical_finfo
Definition: typcache.h:102
int16 typlen
Definition: typcache.h:39
Oid hash_opintype
Definition: typcache.h:60
Oid typcollation
Definition: typcache.h:47
Oid domainBaseType
Definition: typcache.h:114
char typstorage
Definition: typcache.h:42
Oid rng_opfamily
Definition: typcache.h:99
Definition: dsa.c:366
void InitDomainConstraintRef(Oid type_id, DomainConstraintRef *ref, MemoryContext refctx, bool need_exprstate)
Definition: typcache.c:1313
TupleDesc lookup_rowtype_tupdesc(Oid type_id, int32 typmod)
Definition: typcache.c:1833
TupleDesc lookup_rowtype_tupdesc_domain(Oid type_id, int32 typmod, bool noError)
Definition: typcache.c:1889
TupleDesc lookup_rowtype_tupdesc_noerror(Oid type_id, int32 typmod, bool noError)
Definition: typcache.c:1850
void SharedRecordTypmodRegistryInit(SharedRecordTypmodRegistry *, dsm_segment *segment, dsa_area *area)
Definition: typcache.c:2108
void SharedRecordTypmodRegistryAttach(SharedRecordTypmodRegistry *)
Definition: typcache.c:2207
uint64 assign_record_type_identifier(Oid type_id, int32 typmod)
Definition: typcache.c:2045
bool DomainHasConstraints(Oid type_id)
Definition: typcache.c:1400
size_t SharedRecordTypmodRegistryEstimate(void)
Definition: typcache.c:2086
int compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2)
Definition: typcache.c:2477
struct TypeCacheEntry TypeCacheEntry
void assign_record_type_typmod(TupleDesc tupDesc)
Definition: typcache.c:1953
struct DomainConstraintRef DomainConstraintRef
TypeCacheEntry * lookup_type_cache(Oid type_id, int flags)
Definition: typcache.c:346
TupleDesc lookup_rowtype_tupdesc_copy(Oid type_id, int32 typmod)
Definition: typcache.c:1867
void UpdateDomainConstraintRef(DomainConstraintRef *ref)
Definition: typcache.c:1351