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/*-------------------------------------------------------------------------
*
* typcache.h
* Type cache definitions.
*
* The type cache exists to speed lookup of certain information about data
* types that is not directly available from a type's pg_type row.
*
* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/include/utils/typcache.h
*
*-------------------------------------------------------------------------
*/
#ifndef TYPCACHE_H
#define TYPCACHE_H
#include "access/tupdesc.h"
#include "fmgr.h"
/* TypeCacheEnumData is an opaque struct known only within typcache.c */
struct TypeCacheEnumData;
typedef struct TypeCacheEntry
{
/* typeId is the hash lookup key and MUST BE FIRST */
Oid type_id; /* OID of the data type */
/* some subsidiary information copied from the pg_type row */
int16 typlen;
bool typbyval;
char typalign;
char typstorage;
char typtype;
Oid typrelid;
/*
* Information obtained from opfamily entries
*
* These will be InvalidOid if no match could be found, or if the
* information hasn't yet been requested. Also note that for array and
* composite types, typcache.c checks that the contained types are
* comparable or hashable before allowing eq_opr etc to become set.
*/
Oid btree_opf; /* the default btree opclass' family */
Oid btree_opintype; /* the default btree opclass' opcintype */
Oid hash_opf; /* the default hash opclass' family */
Oid hash_opintype; /* the default hash opclass' opcintype */
Oid eq_opr; /* the equality operator */
Oid lt_opr; /* the less-than operator */
Oid gt_opr; /* the greater-than operator */
Oid cmp_proc; /* the btree comparison function */
Oid hash_proc; /* the hash calculation function */
/*
* Pre-set-up fmgr call info for the equality operator, the btree
* comparison function, and the hash calculation function. These are kept
* in the type cache to avoid problems with memory leaks in repeated calls
* to functions such as array_eq, array_cmp, hash_array. There is not
* currently a need to maintain call info for the lt_opr or gt_opr.
*/
FmgrInfo eq_opr_finfo;
FmgrInfo cmp_proc_finfo;
FmgrInfo hash_proc_finfo;
/*
* Tuple descriptor if it's a composite type (row type). NULL if not
* composite or information hasn't yet been requested. (NOTE: this is a
* reference-counted tupledesc.)
*/
TupleDesc tupDesc;
/*
* Fields computed when TYPECACHE_RANGE_INFO is requested. Zeroes if not
* a range type or information hasn't yet been requested. Note that
* rng_cmp_proc_finfo could be different from the element type's default
* btree comparison function.
*/
struct TypeCacheEntry *rngelemtype; /* range's element type */
Oid rng_collation; /* collation for comparisons, if any */
FmgrInfo rng_cmp_proc_finfo; /* comparison function */
FmgrInfo rng_canonical_finfo; /* canonicalization function, if any */
FmgrInfo rng_subdiff_finfo; /* difference function, if any */
/* Private data, for internal use of typcache.c only */
int flags; /* flags about what we've computed */
/*
* Private information about an enum type. NULL if not enum or
* information hasn't been requested.
*/
struct TypeCacheEnumData *enumData;
} TypeCacheEntry;
/* Bit flags to indicate which fields a given caller needs to have set */
#define TYPECACHE_EQ_OPR 0x0001
#define TYPECACHE_LT_OPR 0x0002
#define TYPECACHE_GT_OPR 0x0004
#define TYPECACHE_CMP_PROC 0x0008
#define TYPECACHE_HASH_PROC 0x0010
#define TYPECACHE_EQ_OPR_FINFO 0x0020
#define TYPECACHE_CMP_PROC_FINFO 0x0040
#define TYPECACHE_HASH_PROC_FINFO 0x0080
#define TYPECACHE_TUPDESC 0x0100
#define TYPECACHE_BTREE_OPFAMILY 0x0200
#define TYPECACHE_HASH_OPFAMILY 0x0400
#define TYPECACHE_RANGE_INFO 0x0800
extern TypeCacheEntry *lookup_type_cache(Oid type_id, int flags);
extern TupleDesc lookup_rowtype_tupdesc(Oid type_id, int32 typmod);
extern TupleDesc lookup_rowtype_tupdesc_noerror(Oid type_id, int32 typmod,
bool noError);
extern TupleDesc lookup_rowtype_tupdesc_copy(Oid type_id, int32 typmod);
extern void assign_record_type_typmod(TupleDesc tupDesc);
extern int compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2);
#endif /* TYPCACHE_H */
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