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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) 1996-2018, 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;
44 
45  /*
46  * Information obtained from opfamily entries
47  *
48  * These will be InvalidOid if no match could be found, or if the
49  * information hasn't yet been requested. Also note that for array and
50  * composite types, typcache.c checks that the contained types are
51  * comparable or hashable before allowing eq_opr etc to become set.
52  */
53  Oid btree_opf; /* the default btree opclass' family */
54  Oid btree_opintype; /* the default btree opclass' opcintype */
55  Oid hash_opf; /* the default hash opclass' family */
56  Oid hash_opintype; /* the default hash opclass' opcintype */
57  Oid eq_opr; /* the equality operator */
58  Oid lt_opr; /* the less-than operator */
59  Oid gt_opr; /* the greater-than operator */
60  Oid cmp_proc; /* the btree comparison function */
61  Oid hash_proc; /* the hash calculation function */
62  Oid hash_extended_proc; /* the extended hash calculation function */
63 
64  /*
65  * Pre-set-up fmgr call info for the equality operator, the btree
66  * comparison function, and the hash calculation function. These are kept
67  * in the type cache to avoid problems with memory leaks in repeated calls
68  * to functions such as array_eq, array_cmp, hash_array. There is not
69  * currently a need to maintain call info for the lt_opr or gt_opr.
70  */
75 
76  /*
77  * Tuple descriptor if it's a composite type (row type). NULL if not
78  * composite or information hasn't yet been requested. (NOTE: this is a
79  * reference-counted tupledesc.)
80  *
81  * To simplify caching dependent info, tupDesc_identifier is an identifier
82  * for this tupledesc that is unique for the life of the process, and
83  * changes anytime the tupledesc does. Zero if not yet determined.
84  */
87 
88  /*
89  * Fields computed when TYPECACHE_RANGE_INFO is requested. Zeroes if not
90  * a range type or information hasn't yet been requested. Note that
91  * rng_cmp_proc_finfo could be different from the element type's default
92  * btree comparison function.
93  */
94  struct TypeCacheEntry *rngelemtype; /* range's element type */
95  Oid rng_collation; /* collation for comparisons, if any */
96  FmgrInfo rng_cmp_proc_finfo; /* comparison function */
97  FmgrInfo rng_canonical_finfo; /* canonicalization function, if any */
98  FmgrInfo rng_subdiff_finfo; /* difference function, if any */
99 
100  /*
101  * Domain's base type and typmod if it's a domain type. Zeroes if not
102  * domain, or if information hasn't been requested.
103  */
106 
107  /*
108  * Domain constraint data if it's a domain type. NULL if not domain, or
109  * if domain has no constraints, or if information hasn't been requested.
110  */
112 
113  /* Private data, for internal use of typcache.c only */
114  int flags; /* flags about what we've computed */
115 
116  /*
117  * Private information about an enum type. NULL if not enum or
118  * information hasn't been requested.
119  */
121 
122  /* We also maintain a list of all known domain-type cache entries */
125 
126 /* Bit flags to indicate which fields a given caller needs to have set */
127 #define TYPECACHE_EQ_OPR 0x0001
128 #define TYPECACHE_LT_OPR 0x0002
129 #define TYPECACHE_GT_OPR 0x0004
130 #define TYPECACHE_CMP_PROC 0x0008
131 #define TYPECACHE_HASH_PROC 0x0010
132 #define TYPECACHE_EQ_OPR_FINFO 0x0020
133 #define TYPECACHE_CMP_PROC_FINFO 0x0040
134 #define TYPECACHE_HASH_PROC_FINFO 0x0080
135 #define TYPECACHE_TUPDESC 0x0100
136 #define TYPECACHE_BTREE_OPFAMILY 0x0200
137 #define TYPECACHE_HASH_OPFAMILY 0x0400
138 #define TYPECACHE_RANGE_INFO 0x0800
139 #define TYPECACHE_DOMAIN_BASE_INFO 0x1000
140 #define TYPECACHE_DOMAIN_CONSTR_INFO 0x2000
141 #define TYPECACHE_HASH_EXTENDED_PROC 0x4000
142 #define TYPECACHE_HASH_EXTENDED_PROC_FINFO 0x8000
143 
144 /* This value will not equal any valid tupledesc identifier, nor 0 */
145 #define INVALID_TUPLEDESC_IDENTIFIER ((uint64) 1)
146 
147 /*
148  * Callers wishing to maintain a long-lived reference to a domain's constraint
149  * set must store it in one of these. Use InitDomainConstraintRef() and
150  * UpdateDomainConstraintRef() to manage it. Note: DomainConstraintState is
151  * considered an executable expression type, so it's defined in execnodes.h.
152  */
153 typedef struct DomainConstraintRef
154 {
155  List *constraints; /* list of DomainConstraintState nodes */
156  MemoryContext refctx; /* context holding DomainConstraintRef */
157  TypeCacheEntry *tcache; /* typcache entry for domain type */
158  bool need_exprstate; /* does caller need check_exprstate? */
159 
160  /* Management data --- treat these fields as private to typcache.c */
161  DomainConstraintCache *dcc; /* current constraints, or NULL if none */
162  MemoryContextCallback callback; /* used to release refcount when done */
164 
166 
168 
170  MemoryContext refctx, bool need_exprstate);
171 
173 
174 extern bool DomainHasConstraints(Oid type_id);
175 
177 
179  bool noError);
180 
182 
184  bool noError);
185 
187 
188 extern uint64 assign_record_type_identifier(Oid type_id, int32 typmod);
189 
190 extern int compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2);
191 
192 extern size_t SharedRecordTypmodRegistryEstimate(void);
193 
195  dsm_segment *segment, dsa_area *area);
196 
198 
199 #endif /* TYPCACHE_H */
int compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2)
Definition: typcache.c:2226
MemoryContextCallback callback
Definition: typcache.h:162
signed short int16
Definition: c.h:312
struct TypeCacheEnumData * enumData
Definition: typcache.h:120
Definition: fmgr.h:56
uint64 assign_record_type_identifier(Oid type_id, int32 typmod)
Definition: typcache.c:1836
FmgrInfo rng_cmp_proc_finfo
Definition: typcache.h:96
DomainConstraintCache * dcc
Definition: typcache.h:161
TupleDesc lookup_rowtype_tupdesc_copy(Oid type_id, int32 typmod)
Definition: typcache.c:1675
Oid hash_opintype
Definition: typcache.h:56
DomainConstraintCache * domainData
Definition: typcache.h:111
void InitDomainConstraintRef(Oid type_id, DomainConstraintRef *ref, MemoryContext refctx, bool need_exprstate)
Definition: typcache.c:1191
struct TypeCacheEntry TypeCacheEntry
size_t SharedRecordTypmodRegistryEstimate(void)
Definition: typcache.c:1877
TupleDesc lookup_rowtype_tupdesc_domain(Oid type_id, int32 typmod, bool noError)
Definition: typcache.c:1697
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:1641
bool typbyval
Definition: typcache.h:38
signed int int32
Definition: c.h:313
Oid domainBaseType
Definition: typcache.h:104
FmgrInfo rng_subdiff_finfo
Definition: typcache.h:98
FmgrInfo cmp_proc_finfo
Definition: typcache.h:72
struct TypeCacheEntry * nextDomain
Definition: typcache.h:123
void UpdateDomainConstraintRef(DomainConstraintRef *ref)
Definition: typcache.c:1229
void assign_record_type_typmod(TupleDesc tupDesc)
Definition: typcache.c:1761
char typstorage
Definition: typcache.h:40
int32 domainBaseTypmod
Definition: typcache.h:105
void SharedRecordTypmodRegistryAttach(SharedRecordTypmodRegistry *)
Definition: typcache.c:1998
Oid hash_extended_proc
Definition: typcache.h:62
FmgrInfo hash_proc_finfo
Definition: typcache.h:73
FmgrInfo rng_canonical_finfo
Definition: typcache.h:97
MemoryContext refctx
Definition: typcache.h:156
struct TypeCacheEntry * rngelemtype
Definition: typcache.h:94
struct DomainConstraintRef DomainConstraintRef
FmgrInfo hash_extended_proc_finfo
Definition: typcache.h:74
Oid btree_opintype
Definition: typcache.h:54
FmgrInfo eq_opr_finfo
Definition: typcache.h:71
char typtype
Definition: typcache.h:41
bool DomainHasConstraints(Oid type_id)
Definition: typcache.c:1278
void SharedRecordTypmodRegistryInit(SharedRecordTypmodRegistry *, dsm_segment *segment, dsa_area *area)
Definition: typcache.c:1899
TypeCacheEntry * tcache
Definition: typcache.h:157
Oid rng_collation
Definition: typcache.h:95
uint64 tupDesc_identifier
Definition: typcache.h:86
Definition: dsa.c:354
char typalign
Definition: typcache.h:39
Definition: pg_list.h:45
TupleDesc tupDesc
Definition: typcache.h:85
TypeCacheEntry * lookup_type_cache(Oid type_id, int flags)
Definition: typcache.c:321
TupleDesc lookup_rowtype_tupdesc_noerror(Oid type_id, int32 typmod, bool noError)
Definition: typcache.c:1658