1 /*-------------------------------------------------------------------------
4 * Type cache definitions.
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.
9 * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
10 * Portions Copyright (c) 1994, Regents of the University of California
12 * src/include/utils/typcache.h
14 *-------------------------------------------------------------------------
19 #include "access/tupdesc.h"
21 #include "storage/dsm.h"
22 #include "utils/dsa.h"
25 /* DomainConstraintCache is an opaque struct known only within typcache.c */
26 typedef struct DomainConstraintCache DomainConstraintCache;
28 /* TypeCacheEnumData is an opaque struct known only within typcache.c */
29 struct TypeCacheEnumData;
31 typedef struct TypeCacheEntry
33 /* typeId is the hash lookup key and MUST BE FIRST */
34 Oid type_id; /* OID of the data type */
36 /* some subsidiary information copied from the pg_type row */
47 * Information obtained from opfamily entries
49 * These will be InvalidOid if no match could be found, or if the
50 * information hasn't yet been requested. Also note that for array and
51 * composite types, typcache.c checks that the contained types are
52 * comparable or hashable before allowing eq_opr etc to become set.
54 Oid btree_opf; /* the default btree opclass' family */
55 Oid btree_opintype; /* the default btree opclass' opcintype */
56 Oid hash_opf; /* the default hash opclass' family */
57 Oid hash_opintype; /* the default hash opclass' opcintype */
58 Oid eq_opr; /* the equality operator */
59 Oid lt_opr; /* the less-than operator */
60 Oid gt_opr; /* the greater-than operator */
61 Oid cmp_proc; /* the btree comparison function */
62 Oid hash_proc; /* the hash calculation function */
63 Oid hash_extended_proc; /* the extended hash calculation function */
66 * Pre-set-up fmgr call info for the equality operator, the btree
67 * comparison function, and the hash calculation function. These are kept
68 * in the type cache to avoid problems with memory leaks in repeated calls
69 * to functions such as array_eq, array_cmp, hash_array. There is not
70 * currently a need to maintain call info for the lt_opr or gt_opr.
72 FmgrInfo eq_opr_finfo;
73 FmgrInfo cmp_proc_finfo;
74 FmgrInfo hash_proc_finfo;
75 FmgrInfo hash_extended_proc_finfo;
78 * Tuple descriptor if it's a composite type (row type). NULL if not
79 * composite or information hasn't yet been requested. (NOTE: this is a
80 * reference-counted tupledesc.)
82 * To simplify caching dependent info, tupDesc_identifier is an identifier
83 * for this tupledesc that is unique for the life of the process, and
84 * changes anytime the tupledesc does. Zero if not yet determined.
87 uint64 tupDesc_identifier;
90 * Fields computed when TYPECACHE_RANGE_INFO is requested. Zeroes if not
91 * a range type or information hasn't yet been requested. Note that
92 * rng_cmp_proc_finfo could be different from the element type's default
93 * btree comparison function.
95 struct TypeCacheEntry *rngelemtype; /* range's element type */
96 Oid rng_collation; /* collation for comparisons, if any */
97 FmgrInfo rng_cmp_proc_finfo; /* comparison function */
98 FmgrInfo rng_canonical_finfo; /* canonicalization function, if any */
99 FmgrInfo rng_subdiff_finfo; /* difference function, if any */
102 * Domain's base type and typmod if it's a domain type. Zeroes if not
103 * domain, or if information hasn't been requested.
106 int32 domainBaseTypmod;
109 * Domain constraint data if it's a domain type. NULL if not domain, or
110 * if domain has no constraints, or if information hasn't been requested.
112 DomainConstraintCache *domainData;
114 /* Private data, for internal use of typcache.c only */
115 int flags; /* flags about what we've computed */
118 * Private information about an enum type. NULL if not enum or
119 * information hasn't been requested.
121 struct TypeCacheEnumData *enumData;
123 /* We also maintain a list of all known domain-type cache entries */
124 struct TypeCacheEntry *nextDomain;
127 /* Bit flags to indicate which fields a given caller needs to have set */
128 #define TYPECACHE_EQ_OPR 0x0001
129 #define TYPECACHE_LT_OPR 0x0002
130 #define TYPECACHE_GT_OPR 0x0004
131 #define TYPECACHE_CMP_PROC 0x0008
132 #define TYPECACHE_HASH_PROC 0x0010
133 #define TYPECACHE_EQ_OPR_FINFO 0x0020
134 #define TYPECACHE_CMP_PROC_FINFO 0x0040
135 #define TYPECACHE_HASH_PROC_FINFO 0x0080
136 #define TYPECACHE_TUPDESC 0x0100
137 #define TYPECACHE_BTREE_OPFAMILY 0x0200
138 #define TYPECACHE_HASH_OPFAMILY 0x0400
139 #define TYPECACHE_RANGE_INFO 0x0800
140 #define TYPECACHE_DOMAIN_BASE_INFO 0x1000
141 #define TYPECACHE_DOMAIN_CONSTR_INFO 0x2000
142 #define TYPECACHE_HASH_EXTENDED_PROC 0x4000
143 #define TYPECACHE_HASH_EXTENDED_PROC_FINFO 0x8000
145 /* This value will not equal any valid tupledesc identifier, nor 0 */
146 #define INVALID_TUPLEDESC_IDENTIFIER ((uint64) 1)
149 * Callers wishing to maintain a long-lived reference to a domain's constraint
150 * set must store it in one of these. Use InitDomainConstraintRef() and
151 * UpdateDomainConstraintRef() to manage it. Note: DomainConstraintState is
152 * considered an executable expression type, so it's defined in execnodes.h.
154 typedef struct DomainConstraintRef
156 List *constraints; /* list of DomainConstraintState nodes */
157 MemoryContext refctx; /* context holding DomainConstraintRef */
158 TypeCacheEntry *tcache; /* typcache entry for domain type */
159 bool need_exprstate; /* does caller need check_exprstate? */
161 /* Management data --- treat these fields as private to typcache.c */
162 DomainConstraintCache *dcc; /* current constraints, or NULL if none */
163 MemoryContextCallback callback; /* used to release refcount when done */
164 } DomainConstraintRef;
166 typedef struct SharedRecordTypmodRegistry SharedRecordTypmodRegistry;
168 extern TypeCacheEntry *lookup_type_cache(Oid type_id, int flags);
170 extern void InitDomainConstraintRef(Oid type_id, DomainConstraintRef *ref,
171 MemoryContext refctx, bool need_exprstate);
173 extern void UpdateDomainConstraintRef(DomainConstraintRef *ref);
175 extern bool DomainHasConstraints(Oid type_id);
177 extern TupleDesc lookup_rowtype_tupdesc(Oid type_id, int32 typmod);
179 extern TupleDesc lookup_rowtype_tupdesc_noerror(Oid type_id, int32 typmod,
182 extern TupleDesc lookup_rowtype_tupdesc_copy(Oid type_id, int32 typmod);
184 extern TupleDesc lookup_rowtype_tupdesc_domain(Oid type_id, int32 typmod,
187 extern void assign_record_type_typmod(TupleDesc tupDesc);
189 extern uint64 assign_record_type_identifier(Oid type_id, int32 typmod);
191 extern int compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2);
193 extern size_t SharedRecordTypmodRegistryEstimate(void);
195 extern void SharedRecordTypmodRegistryInit(SharedRecordTypmodRegistry *,
196 dsm_segment *segment, dsa_area *area);
198 extern void SharedRecordTypmodRegistryAttach(SharedRecordTypmodRegistry *);
200 #endif /* TYPCACHE_H */