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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) 1996-2021, 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_collation; /* collation for comparisons, if any */
100  FmgrInfo rng_cmp_proc_finfo; /* comparison function */
101  FmgrInfo rng_canonical_finfo; /* canonicalization function, if any */
102  FmgrInfo rng_subdiff_finfo; /* difference function, if any */
103 
104  /*
105  * Fields computed when TYPECACHE_MULTIRANGE_INFO is required.
106  */
107  struct TypeCacheEntry *rngtype; /* multirange's range underlying type */
108 
109  /*
110  * Domain's base type and typmod if it's a domain type. Zeroes if not
111  * domain, or if information hasn't been requested.
112  */
115 
116  /*
117  * Domain constraint data if it's a domain type. NULL if not domain, or
118  * if domain has no constraints, or if information hasn't been requested.
119  */
121 
122  /* Private data, for internal use of typcache.c only */
123  int flags; /* flags about what we've computed */
124 
125  /*
126  * Private information about an enum type. NULL if not enum or
127  * information hasn't been requested.
128  */
130 
131  /* We also maintain a list of all known domain-type cache entries */
134 
135 /* Bit flags to indicate which fields a given caller needs to have set */
136 #define TYPECACHE_EQ_OPR 0x00001
137 #define TYPECACHE_LT_OPR 0x00002
138 #define TYPECACHE_GT_OPR 0x00004
139 #define TYPECACHE_CMP_PROC 0x00008
140 #define TYPECACHE_HASH_PROC 0x00010
141 #define TYPECACHE_EQ_OPR_FINFO 0x00020
142 #define TYPECACHE_CMP_PROC_FINFO 0x00040
143 #define TYPECACHE_HASH_PROC_FINFO 0x00080
144 #define TYPECACHE_TUPDESC 0x00100
145 #define TYPECACHE_BTREE_OPFAMILY 0x00200
146 #define TYPECACHE_HASH_OPFAMILY 0x00400
147 #define TYPECACHE_RANGE_INFO 0x00800
148 #define TYPECACHE_DOMAIN_BASE_INFO 0x01000
149 #define TYPECACHE_DOMAIN_CONSTR_INFO 0x02000
150 #define TYPECACHE_HASH_EXTENDED_PROC 0x04000
151 #define TYPECACHE_HASH_EXTENDED_PROC_FINFO 0x08000
152 #define TYPECACHE_MULTIRANGE_INFO 0x10000
153 
154 /* This value will not equal any valid tupledesc identifier, nor 0 */
155 #define INVALID_TUPLEDESC_IDENTIFIER ((uint64) 1)
156 
157 /*
158  * Callers wishing to maintain a long-lived reference to a domain's constraint
159  * set must store it in one of these. Use InitDomainConstraintRef() and
160  * UpdateDomainConstraintRef() to manage it. Note: DomainConstraintState is
161  * considered an executable expression type, so it's defined in execnodes.h.
162  */
163 typedef struct DomainConstraintRef
164 {
165  List *constraints; /* list of DomainConstraintState nodes */
166  MemoryContext refctx; /* context holding DomainConstraintRef */
167  TypeCacheEntry *tcache; /* typcache entry for domain type */
168  bool need_exprstate; /* does caller need check_exprstate? */
169 
170  /* Management data --- treat these fields as private to typcache.c */
171  DomainConstraintCache *dcc; /* current constraints, or NULL if none */
172  MemoryContextCallback callback; /* used to release refcount when done */
174 
176 
178 
180  MemoryContext refctx, bool need_exprstate);
181 
183 
184 extern bool DomainHasConstraints(Oid type_id);
185 
187 
189  bool noError);
190 
192 
194  bool noError);
195 
197 
198 extern uint64 assign_record_type_identifier(Oid type_id, int32 typmod);
199 
200 extern int compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2);
201 
202 extern size_t SharedRecordTypmodRegistryEstimate(void);
203 
205  dsm_segment *segment, dsa_area *area);
206 
208 
209 #endif /* TYPCACHE_H */
int compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2)
Definition: typcache.c:2471
MemoryContextCallback callback
Definition: typcache.h:172
signed short int16
Definition: c.h:428
struct TypeCacheEnumData * enumData
Definition: typcache.h:129
Definition: fmgr.h:56
uint64 assign_record_type_identifier(Oid type_id, int32 typmod)
Definition: typcache.c:2039
FmgrInfo rng_cmp_proc_finfo
Definition: typcache.h:100
DomainConstraintCache * dcc
Definition: typcache.h:171
TupleDesc lookup_rowtype_tupdesc_copy(Oid type_id, int32 typmod)
Definition: typcache.c:1861
Oid hash_opintype
Definition: typcache.h:60
uint32 type_id_hash
Definition: typcache.h:36
DomainConstraintCache * domainData
Definition: typcache.h:120
void InitDomainConstraintRef(Oid type_id, DomainConstraintRef *ref, MemoryContext refctx, bool need_exprstate)
Definition: typcache.c:1305
struct TypeCacheEntry TypeCacheEntry
Oid typcollation
Definition: typcache.h:47
size_t SharedRecordTypmodRegistryEstimate(void)
Definition: typcache.c:2080
TupleDesc lookup_rowtype_tupdesc_domain(Oid type_id, int32 typmod, bool noError)
Definition: typcache.c:1883
unsigned int Oid
Definition: postgres_ext.h:31
int16 typlen
Definition: typcache.h:39
TupleDesc lookup_rowtype_tupdesc(Oid type_id, int32 typmod)
Definition: typcache.c:1827
bool typbyval
Definition: typcache.h:40
signed int int32
Definition: c.h:429
Oid domainBaseType
Definition: typcache.h:113
FmgrInfo rng_subdiff_finfo
Definition: typcache.h:102
FmgrInfo cmp_proc_finfo
Definition: typcache.h:76
struct TypeCacheEntry * nextDomain
Definition: typcache.h:132
void UpdateDomainConstraintRef(DomainConstraintRef *ref)
Definition: typcache.c:1343
void assign_record_type_typmod(TupleDesc tupDesc)
Definition: typcache.c:1947
char typstorage
Definition: typcache.h:42
int32 domainBaseTypmod
Definition: typcache.h:114
void SharedRecordTypmodRegistryAttach(SharedRecordTypmodRegistry *)
Definition: typcache.c:2201
Oid hash_extended_proc
Definition: typcache.h:66
unsigned int uint32
Definition: c.h:441
FmgrInfo hash_proc_finfo
Definition: typcache.h:77
FmgrInfo rng_canonical_finfo
Definition: typcache.h:101
MemoryContext refctx
Definition: typcache.h:166
struct TypeCacheEntry * rngelemtype
Definition: typcache.h:98
struct DomainConstraintRef DomainConstraintRef
FmgrInfo hash_extended_proc_finfo
Definition: typcache.h:78
Oid btree_opintype
Definition: typcache.h:58
FmgrInfo eq_opr_finfo
Definition: typcache.h:75
char typtype
Definition: typcache.h:43
bool DomainHasConstraints(Oid type_id)
Definition: typcache.c:1392
void SharedRecordTypmodRegistryInit(SharedRecordTypmodRegistry *, dsm_segment *segment, dsa_area *area)
Definition: typcache.c:2102
TypeCacheEntry * tcache
Definition: typcache.h:167
Oid rng_collation
Definition: typcache.h:99
uint64 tupDesc_identifier
Definition: typcache.h:90
struct TypeCacheEntry * rngtype
Definition: typcache.h:107
Oid typsubscript
Definition: typcache.h:45
Definition: dsa.c:354
char typalign
Definition: typcache.h:41
Definition: pg_list.h:50
TupleDesc tupDesc
Definition: typcache.h:89
TypeCacheEntry * lookup_type_cache(Oid type_id, int flags)
Definition: typcache.c:339
TupleDesc lookup_rowtype_tupdesc_noerror(Oid type_id, int32 typmod, bool noError)
Definition: typcache.c:1844