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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) 1996-2019, 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  /* some subsidiary information copied from the pg_type row */
38  bool typbyval;
39  char typalign;
40  char typstorage;
41  char typtype;
45 
46  /*
47  * Information obtained from opfamily entries
48  *
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.
53  */
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 */
64 
65  /*
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.
71  */
76 
77  /*
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.)
81  *
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.
85  */
88 
89  /*
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.
94  */
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 */
100 
101  /*
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.
104  */
107 
108  /*
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.
111  */
113 
114  /* Private data, for internal use of typcache.c only */
115  int flags; /* flags about what we've computed */
116 
117  /*
118  * Private information about an enum type. NULL if not enum or
119  * information hasn't been requested.
120  */
122 
123  /* We also maintain a list of all known domain-type cache entries */
126 
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
144 
145 /* This value will not equal any valid tupledesc identifier, nor 0 */
146 #define INVALID_TUPLEDESC_IDENTIFIER ((uint64) 1)
147 
148 /*
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.
153  */
154 typedef struct DomainConstraintRef
155 {
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? */
160 
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 */
165 
167 
169 
171  MemoryContext refctx, bool need_exprstate);
172 
174 
175 extern bool DomainHasConstraints(Oid type_id);
176 
178 
180  bool noError);
181 
183 
185  bool noError);
186 
188 
189 extern uint64 assign_record_type_identifier(Oid type_id, int32 typmod);
190 
191 extern int compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2);
192 
193 extern size_t SharedRecordTypmodRegistryEstimate(void);
194 
196  dsm_segment *segment, dsa_area *area);
197 
199 
200 #endif /* TYPCACHE_H */
int compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2)
Definition: typcache.c:2247
MemoryContextCallback callback
Definition: typcache.h:163
signed short int16
Definition: c.h:346
struct TypeCacheEnumData * enumData
Definition: typcache.h:121
Definition: fmgr.h:56
uint64 assign_record_type_identifier(Oid type_id, int32 typmod)
Definition: typcache.c:1847
FmgrInfo rng_cmp_proc_finfo
Definition: typcache.h:97
DomainConstraintCache * dcc
Definition: typcache.h:162
TupleDesc lookup_rowtype_tupdesc_copy(Oid type_id, int32 typmod)
Definition: typcache.c:1686
Oid hash_opintype
Definition: typcache.h:57
DomainConstraintCache * domainData
Definition: typcache.h:112
void InitDomainConstraintRef(Oid type_id, DomainConstraintRef *ref, MemoryContext refctx, bool need_exprstate)
Definition: typcache.c:1202
struct TypeCacheEntry TypeCacheEntry
Oid typcollation
Definition: typcache.h:44
size_t SharedRecordTypmodRegistryEstimate(void)
Definition: typcache.c:1888
TupleDesc lookup_rowtype_tupdesc_domain(Oid type_id, int32 typmod, bool noError)
Definition: typcache.c:1708
unsigned int Oid
Definition: postgres_ext.h:31
int16 typlen
Definition: typcache.h:37
TupleDesc lookup_rowtype_tupdesc(Oid type_id, int32 typmod)
Definition: typcache.c:1652
bool typbyval
Definition: typcache.h:38
signed int int32
Definition: c.h:347
Oid domainBaseType
Definition: typcache.h:105
FmgrInfo rng_subdiff_finfo
Definition: typcache.h:99
FmgrInfo cmp_proc_finfo
Definition: typcache.h:73
struct TypeCacheEntry * nextDomain
Definition: typcache.h:124
void UpdateDomainConstraintRef(DomainConstraintRef *ref)
Definition: typcache.c:1240
void assign_record_type_typmod(TupleDesc tupDesc)
Definition: typcache.c:1772
char typstorage
Definition: typcache.h:40
int32 domainBaseTypmod
Definition: typcache.h:106
void SharedRecordTypmodRegistryAttach(SharedRecordTypmodRegistry *)
Definition: typcache.c:2009
Oid hash_extended_proc
Definition: typcache.h:63
FmgrInfo hash_proc_finfo
Definition: typcache.h:74
FmgrInfo rng_canonical_finfo
Definition: typcache.h:98
MemoryContext refctx
Definition: typcache.h:157
struct TypeCacheEntry * rngelemtype
Definition: typcache.h:95
struct DomainConstraintRef DomainConstraintRef
FmgrInfo hash_extended_proc_finfo
Definition: typcache.h:75
Oid btree_opintype
Definition: typcache.h:55
FmgrInfo eq_opr_finfo
Definition: typcache.h:72
char typtype
Definition: typcache.h:41
bool DomainHasConstraints(Oid type_id)
Definition: typcache.c:1289
void SharedRecordTypmodRegistryInit(SharedRecordTypmodRegistry *, dsm_segment *segment, dsa_area *area)
Definition: typcache.c:1910
TypeCacheEntry * tcache
Definition: typcache.h:158
Oid rng_collation
Definition: typcache.h:96
uint64 tupDesc_identifier
Definition: typcache.h:87
Definition: dsa.c:354
char typalign
Definition: typcache.h:39
Definition: pg_list.h:50
TupleDesc tupDesc
Definition: typcache.h:86
TypeCacheEntry * lookup_type_cache(Oid type_id, int flags)
Definition: typcache.c:322
TupleDesc lookup_rowtype_tupdesc_noerror(Oid type_id, int32 typmod, bool noError)
Definition: typcache.c:1669