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apache / cloudberry / refs/heads/reshke-patch-1 / . / src / backend / utils / cache / typcache.c
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/*-------------------------------------------------------------------------
*
* typcache.c
* POSTGRES type cache code
*
* 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. For
* example, we use a type's default btree opclass, or the default hash
* opclass if no btree opclass exists, to determine which operators should
* be used for grouping and sorting the type (GROUP BY, ORDER BY ASC/DESC).
*
* Several seemingly-odd choices have been made to support use of the type
* cache by generic array and record handling routines, such as array_eq(),
* record_cmp(), and hash_array(). Because those routines are used as index
* support operations, they cannot leak memory. To allow them to execute
* efficiently, all information that they would like to re-use across calls
* is kept in the type cache.
*
* Once created, a type cache entry lives as long as the backend does, so
* there is no need for a call to release a cache entry. If the type is
* dropped, the cache entry simply becomes wasted storage. This is not
* expected to happen often, and assuming that typcache entries are good
* permanently allows caching pointers to them in long-lived places.
*
* We have some provisions for updating cache entries if the stored data
* becomes obsolete. Core data extracted from the pg_type row is updated
* when we detect updates to pg_type. Information dependent on opclasses is
* cleared if we detect updates to pg_opclass. We also support clearing the
* tuple descriptor and operator/function parts of a rowtype's cache entry,
* since those may need to change as a consequence of ALTER TABLE. Domain
* constraint changes are also tracked properly.
*
*
* Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* src/backend/utils/cache/typcache.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <limits.h>
#include "access/hash.h"
#include "access/htup_details.h"
#include "access/nbtree.h"
#include "access/parallel.h"
#include "access/relation.h"
#include "access/session.h"
#include "access/table.h"
#include "catalog/pg_am.h"
#include "catalog/pg_constraint.h"
#include "catalog/pg_enum.h"
#include "catalog/pg_operator.h"
#include "catalog/pg_range.h"
#include "catalog/pg_type.h"
#include "commands/defrem.h"
#include "executor/executor.h"
#include "lib/dshash.h"
#include "optimizer/optimizer.h"
#include "storage/lwlock.h"
#include "utils/builtins.h"
#include "utils/catcache.h"
#include "utils/fmgroids.h"
#include "utils/inval.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/rel.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"
#include "utils/typcache.h"
#include "cdb/cdbvars.h"
#include "cdb/cdbendpoint.h"
/* The main type cache hashtable searched by lookup_type_cache */
static HTAB *TypeCacheHash = NULL;
/* List of type cache entries for domain types */
static TypeCacheEntry *firstDomainTypeEntry = NULL;
/* Private flag bits in the TypeCacheEntry.flags field */
#define TCFLAGS_HAVE_PG_TYPE_DATA 0x000001
#define TCFLAGS_CHECKED_BTREE_OPCLASS 0x000002
#define TCFLAGS_CHECKED_HASH_OPCLASS 0x000004
#define TCFLAGS_CHECKED_EQ_OPR 0x000008
#define TCFLAGS_CHECKED_LT_OPR 0x000010
#define TCFLAGS_CHECKED_GT_OPR 0x000020
#define TCFLAGS_CHECKED_CMP_PROC 0x000040
#define TCFLAGS_CHECKED_HASH_PROC 0x000080
#define TCFLAGS_CHECKED_HASH_EXTENDED_PROC 0x000100
#define TCFLAGS_CHECKED_ELEM_PROPERTIES 0x000200
#define TCFLAGS_HAVE_ELEM_EQUALITY 0x000400
#define TCFLAGS_HAVE_ELEM_COMPARE 0x000800
#define TCFLAGS_HAVE_ELEM_HASHING 0x001000
#define TCFLAGS_HAVE_ELEM_EXTENDED_HASHING 0x002000
#define TCFLAGS_CHECKED_FIELD_PROPERTIES 0x004000
#define TCFLAGS_HAVE_FIELD_EQUALITY 0x008000
#define TCFLAGS_HAVE_FIELD_COMPARE 0x010000
#define TCFLAGS_HAVE_FIELD_HASHING 0x020000
#define TCFLAGS_HAVE_FIELD_EXTENDED_HASHING 0x040000
#define TCFLAGS_CHECKED_DOMAIN_CONSTRAINTS 0x080000
#define TCFLAGS_DOMAIN_BASE_IS_COMPOSITE 0x100000
/* The flags associated with equality/comparison/hashing are all but these: */
#define TCFLAGS_OPERATOR_FLAGS \
(~(TCFLAGS_HAVE_PG_TYPE_DATA | \
TCFLAGS_CHECKED_DOMAIN_CONSTRAINTS | \
TCFLAGS_DOMAIN_BASE_IS_COMPOSITE))
/*
* Data stored about a domain type's constraints. Note that we do not create
* this struct for the common case of a constraint-less domain; we just set
* domainData to NULL to indicate that.
*
* Within a DomainConstraintCache, we store expression plan trees, but the
* check_exprstate fields of the DomainConstraintState nodes are just NULL.
* When needed, expression evaluation nodes are built by flat-copying the
* DomainConstraintState nodes and applying ExecInitExpr to check_expr.
* Such a node tree is not part of the DomainConstraintCache, but is
* considered to belong to a DomainConstraintRef.
*/
struct DomainConstraintCache
{
List *constraints; /* list of DomainConstraintState nodes */
MemoryContext dccContext; /* memory context holding all associated data */
long dccRefCount; /* number of references to this struct */
};
/* Private information to support comparisons of enum values */
typedef struct
{
Oid enum_oid; /* OID of one enum value */
float4 sort_order; /* its sort position */
} EnumItem;
typedef struct TypeCacheEnumData
{
Oid bitmap_base; /* OID corresponding to bit 0 of bitmapset */
Bitmapset *sorted_values; /* Set of OIDs known to be in order */
int num_values; /* total number of values in enum */
EnumItem enum_values[FLEXIBLE_ARRAY_MEMBER];
} TypeCacheEnumData;
/*
* We use a separate table for storing the definitions of non-anonymous
* record types. Once defined, a record type will be remembered for the
* life of the backend. Subsequent uses of the "same" record type (where
* sameness means equalTupleDescs) will refer to the existing table entry.
*
* Stored record types are remembered in a linear array of TupleDescs,
* which can be indexed quickly with the assigned typmod. There is also
* a hash table to speed searches for matching TupleDescs.
*/
typedef struct RecordCacheEntry
{
TupleDesc tupdesc;
} RecordCacheEntry;
/*
* To deal with non-anonymous record types that are exchanged by backends
* involved in a parallel query, we also need a shared version of the above.
*/
struct SharedRecordTypmodRegistry
{
/* A hash table for finding a matching TupleDesc. */
dshash_table_handle record_table_handle;
/* A hash table for finding a TupleDesc by typmod. */
dshash_table_handle typmod_table_handle;
/* A source of new record typmod numbers. */
pg_atomic_uint32 next_typmod;
};
/*
* When using shared tuple descriptors as hash table keys we need a way to be
* able to search for an equal shared TupleDesc using a backend-local
* TupleDesc. So we use this type which can hold either, and hash and compare
* functions that know how to handle both.
*/
typedef struct SharedRecordTableKey
{
union
{
TupleDesc local_tupdesc;
dsa_pointer shared_tupdesc;
} u;
bool shared;
} SharedRecordTableKey;
/*
* The shared version of RecordCacheEntry. This lets us look up a typmod
* using a TupleDesc which may be in local or shared memory.
*/
typedef struct SharedRecordTableEntry
{
SharedRecordTableKey key;
} SharedRecordTableEntry;
/*
* An entry in SharedRecordTypmodRegistry's typmod table. This lets us look
* up a TupleDesc in shared memory using a typmod.
*/
typedef struct SharedTypmodTableEntry
{
uint32 typmod;
dsa_pointer shared_tupdesc;
} SharedTypmodTableEntry;
/*
* A comparator function for SharedRecordTableKey.
*/
static int
shared_record_table_compare(const void *a, const void *b, size_t size,
void *arg)
{
dsa_area *area = (dsa_area *) arg;
SharedRecordTableKey *k1 = (SharedRecordTableKey *) a;
SharedRecordTableKey *k2 = (SharedRecordTableKey *) b;
TupleDesc t1;
TupleDesc t2;
if (k1->shared)
t1 = (TupleDesc) dsa_get_address(area, k1->u.shared_tupdesc);
else
t1 = k1->u.local_tupdesc;
if (k2->shared)
t2 = (TupleDesc) dsa_get_address(area, k2->u.shared_tupdesc);
else
t2 = k2->u.local_tupdesc;
return equalTupleDescs(t1, t2, true) ? 0 : 1;
}
/*
* A hash function for SharedRecordTableKey.
*/
static uint32
shared_record_table_hash(const void *a, size_t size, void *arg)
{
dsa_area *area = (dsa_area *) arg;
SharedRecordTableKey *k = (SharedRecordTableKey *) a;
TupleDesc t;
if (k->shared)
t = (TupleDesc) dsa_get_address(area, k->u.shared_tupdesc);
else
t = k->u.local_tupdesc;
return hashTupleDesc(t);
}
/* Parameters for SharedRecordTypmodRegistry's TupleDesc table. */
static const dshash_parameters srtr_record_table_params = {
sizeof(SharedRecordTableKey), /* unused */
sizeof(SharedRecordTableEntry),
shared_record_table_compare,
shared_record_table_hash,
LWTRANCHE_PER_SESSION_RECORD_TYPE
};
/* Parameters for SharedRecordTypmodRegistry's typmod hash table. */
static const dshash_parameters srtr_typmod_table_params = {
sizeof(uint32),
sizeof(SharedTypmodTableEntry),
dshash_memcmp,
dshash_memhash,
LWTRANCHE_PER_SESSION_RECORD_TYPMOD
};
/* hashtable for recognizing registered record types */
static HTAB *RecordCacheHash = NULL;
/* arrays of info about registered record types, indexed by assigned typmod */
static TupleDesc *RecordCacheArray = NULL;
static uint64 *RecordIdentifierArray = NULL;
static int32 RecordCacheArrayLen = 0; /* allocated length of above arrays */
int32 NextRecordTypmod = 0; /* number of entries used */
/*
* Process-wide counter for generating unique tupledesc identifiers.
* Zero and one (INVALID_TUPLEDESC_IDENTIFIER) aren't allowed to be chosen
* as identifiers, so we start the counter at INVALID_TUPLEDESC_IDENTIFIER.
*/
static uint64 tupledesc_id_counter = INVALID_TUPLEDESC_IDENTIFIER;
static void load_typcache_tupdesc(TypeCacheEntry *typentry);
static void load_rangetype_info(TypeCacheEntry *typentry);
static void load_multirangetype_info(TypeCacheEntry *typentry);
static void load_domaintype_info(TypeCacheEntry *typentry);
static int dcs_cmp(const void *a, const void *b);
static void decr_dcc_refcount(DomainConstraintCache *dcc);
static void dccref_deletion_callback(void *arg);
static List *prep_domain_constraints(List *constraints, MemoryContext execctx);
static bool array_element_has_equality(TypeCacheEntry *typentry);
static bool array_element_has_compare(TypeCacheEntry *typentry);
static bool array_element_has_hashing(TypeCacheEntry *typentry);
static bool array_element_has_extended_hashing(TypeCacheEntry *typentry);
static void cache_array_element_properties(TypeCacheEntry *typentry);
static bool record_fields_have_equality(TypeCacheEntry *typentry);
static bool record_fields_have_compare(TypeCacheEntry *typentry);
static bool record_fields_have_hashing(TypeCacheEntry *typentry);
static bool record_fields_have_extended_hashing(TypeCacheEntry *typentry);
static void cache_record_field_properties(TypeCacheEntry *typentry);
static bool range_element_has_hashing(TypeCacheEntry *typentry);
static bool range_element_has_extended_hashing(TypeCacheEntry *typentry);
static void cache_range_element_properties(TypeCacheEntry *typentry);
static bool multirange_element_has_hashing(TypeCacheEntry *typentry);
static bool multirange_element_has_extended_hashing(TypeCacheEntry *typentry);
static void cache_multirange_element_properties(TypeCacheEntry *typentry);
static void TypeCacheRelCallback(Datum arg, Oid relid);
static void TypeCacheTypCallback(Datum arg, int cacheid, uint32 hashvalue);
static void TypeCacheOpcCallback(Datum arg, int cacheid, uint32 hashvalue);
static void TypeCacheConstrCallback(Datum arg, int cacheid, uint32 hashvalue);
static void load_enum_cache_data(TypeCacheEntry *tcache);
static EnumItem *find_enumitem(TypeCacheEnumData *enumdata, Oid arg);
static int enum_oid_cmp(const void *left, const void *right);
static void shared_record_typmod_registry_detach(dsm_segment *segment,
Datum datum);
static TupleDesc find_or_make_matching_shared_tupledesc(TupleDesc tupdesc);
static dsa_pointer share_tupledesc(dsa_area *area, TupleDesc tupdesc,
uint32 typmod);
/*
* lookup_type_cache
*
* Fetch the type cache entry for the specified datatype, and make sure that
* all the fields requested by bits in 'flags' are valid.
*
* The result is never NULL --- we will ereport() if the passed type OID is
* invalid. Note however that we may fail to find one or more of the
* values requested by 'flags'; the caller needs to check whether the fields
* are InvalidOid or not.
*/
TypeCacheEntry *
lookup_type_cache(Oid type_id, int flags)
{
TypeCacheEntry *typentry;
bool found;
if (TypeCacheHash == NULL)
{
/* First time through: initialize the hash table */
HASHCTL ctl;
ctl.keysize = sizeof(Oid);
ctl.entrysize = sizeof(TypeCacheEntry);
TypeCacheHash = hash_create("Type information cache", 64,
&ctl, HASH_ELEM | HASH_BLOBS);
/* Also set up callbacks for SI invalidations */
CacheRegisterRelcacheCallback(TypeCacheRelCallback, (Datum) 0);
CacheRegisterSyscacheCallback(TYPEOID, TypeCacheTypCallback, (Datum) 0);
CacheRegisterSyscacheCallback(CLAOID, TypeCacheOpcCallback, (Datum) 0);
CacheRegisterSyscacheCallback(CONSTROID, TypeCacheConstrCallback, (Datum) 0);
/* Also make sure CacheMemoryContext exists */
if (!CacheMemoryContext)
CreateCacheMemoryContext();
}
/* Try to look up an existing entry */
typentry = (TypeCacheEntry *) hash_search(TypeCacheHash,
(void *) &type_id,
HASH_FIND, NULL);
if (typentry == NULL)
{
/*
* If we didn't find one, we want to make one. But first look up the
* pg_type row, just to make sure we don't make a cache entry for an
* invalid type OID. If the type OID is not valid, present a
* user-facing error, since some code paths such as domain_in() allow
* this function to be reached with a user-supplied OID.
*/
HeapTuple tp;
Form_pg_type typtup;
tp = SearchSysCache1(TYPEOID, ObjectIdGetDatum(type_id));
if (!HeapTupleIsValid(tp))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("type with OID %u does not exist", type_id)));
typtup = (Form_pg_type) GETSTRUCT(tp);
if (!typtup->typisdefined)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("type \"%s\" is only a shell",
NameStr(typtup->typname))));
/* Now make the typcache entry */
typentry = (TypeCacheEntry *) hash_search(TypeCacheHash,
(void *) &type_id,
HASH_ENTER, &found);
Assert(!found); /* it wasn't there a moment ago */
MemSet(typentry, 0, sizeof(TypeCacheEntry));
/* These fields can never change, by definition */
typentry->type_id = type_id;
typentry->type_id_hash = GetSysCacheHashValue1(TYPEOID,
ObjectIdGetDatum(type_id));
/* Keep this part in sync with the code below */
typentry->typlen = typtup->typlen;
typentry->typbyval = typtup->typbyval;
typentry->typalign = typtup->typalign;
typentry->typstorage = typtup->typstorage;
typentry->typtype = typtup->typtype;
typentry->typrelid = typtup->typrelid;
typentry->typsubscript = typtup->typsubscript;
typentry->typelem = typtup->typelem;
typentry->typcollation = typtup->typcollation;
typentry->flags |= TCFLAGS_HAVE_PG_TYPE_DATA;
/* If it's a domain, immediately thread it into the domain cache list */
if (typentry->typtype == TYPTYPE_DOMAIN)
{
typentry->nextDomain = firstDomainTypeEntry;
firstDomainTypeEntry = typentry;
}
ReleaseSysCache(tp);
}
else if (!(typentry->flags & TCFLAGS_HAVE_PG_TYPE_DATA))
{
/*
* We have an entry, but its pg_type row got changed, so reload the
* data obtained directly from pg_type.
*/
HeapTuple tp;
Form_pg_type typtup;
tp = SearchSysCache1(TYPEOID, ObjectIdGetDatum(type_id));
if (!HeapTupleIsValid(tp))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("type with OID %u does not exist", type_id)));
typtup = (Form_pg_type) GETSTRUCT(tp);
if (!typtup->typisdefined)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("type \"%s\" is only a shell",
NameStr(typtup->typname))));
/*
* Keep this part in sync with the code above. Many of these fields
* shouldn't ever change, particularly typtype, but copy 'em anyway.
*/
typentry->typlen = typtup->typlen;
typentry->typbyval = typtup->typbyval;
typentry->typalign = typtup->typalign;
typentry->typstorage = typtup->typstorage;
typentry->typtype = typtup->typtype;
typentry->typrelid = typtup->typrelid;
typentry->typsubscript = typtup->typsubscript;
typentry->typelem = typtup->typelem;
typentry->typcollation = typtup->typcollation;
typentry->flags |= TCFLAGS_HAVE_PG_TYPE_DATA;
ReleaseSysCache(tp);
}
/*
* Look up opclasses if we haven't already and any dependent info is
* requested.
*/
if ((flags & (TYPECACHE_EQ_OPR | TYPECACHE_LT_OPR | TYPECACHE_GT_OPR |
TYPECACHE_CMP_PROC |
TYPECACHE_EQ_OPR_FINFO | TYPECACHE_CMP_PROC_FINFO |
TYPECACHE_BTREE_OPFAMILY)) &&
!(typentry->flags & TCFLAGS_CHECKED_BTREE_OPCLASS))
{
Oid opclass;
opclass = GetDefaultOpClass(type_id, BTREE_AM_OID);
if (OidIsValid(opclass))
{
typentry->btree_opf = get_opclass_family(opclass);
typentry->btree_opintype = get_opclass_input_type(opclass);
}
else
{
typentry->btree_opf = typentry->btree_opintype = InvalidOid;
}
/*
* Reset information derived from btree opclass. Note in particular
* that we'll redetermine the eq_opr even if we previously found one;
* this matters in case a btree opclass has been added to a type that
* previously had only a hash opclass.
*/
typentry->flags &= ~(TCFLAGS_CHECKED_EQ_OPR |
TCFLAGS_CHECKED_LT_OPR |
TCFLAGS_CHECKED_GT_OPR |
TCFLAGS_CHECKED_CMP_PROC);
typentry->flags |= TCFLAGS_CHECKED_BTREE_OPCLASS;
}
/*
* If we need to look up equality operator, and there's no btree opclass,
* force lookup of hash opclass.
*/
if ((flags & (TYPECACHE_EQ_OPR | TYPECACHE_EQ_OPR_FINFO)) &&
!(typentry->flags & TCFLAGS_CHECKED_EQ_OPR) &&
typentry->btree_opf == InvalidOid)
flags |= TYPECACHE_HASH_OPFAMILY;
if ((flags & (TYPECACHE_HASH_PROC | TYPECACHE_HASH_PROC_FINFO |
TYPECACHE_HASH_EXTENDED_PROC |
TYPECACHE_HASH_EXTENDED_PROC_FINFO |
TYPECACHE_HASH_OPFAMILY)) &&
!(typentry->flags & TCFLAGS_CHECKED_HASH_OPCLASS))
{
Oid opclass;
opclass = GetDefaultOpClass(type_id, HASH_AM_OID);
if (OidIsValid(opclass))
{
typentry->hash_opf = get_opclass_family(opclass);
typentry->hash_opintype = get_opclass_input_type(opclass);
}
else
{
typentry->hash_opf = typentry->hash_opintype = InvalidOid;
}
/*
* Reset information derived from hash opclass. We do *not* reset the
* eq_opr; if we already found one from the btree opclass, that
* decision is still good.
*/
typentry->flags &= ~(TCFLAGS_CHECKED_HASH_PROC |
TCFLAGS_CHECKED_HASH_EXTENDED_PROC);
typentry->flags |= TCFLAGS_CHECKED_HASH_OPCLASS;
}
/*
* Look for requested operators and functions, if we haven't already.
*/
if ((flags & (TYPECACHE_EQ_OPR | TYPECACHE_EQ_OPR_FINFO)) &&
!(typentry->flags & TCFLAGS_CHECKED_EQ_OPR))
{
Oid eq_opr = InvalidOid;
if (typentry->btree_opf != InvalidOid)
eq_opr = get_opfamily_member(typentry->btree_opf,
typentry->btree_opintype,
typentry->btree_opintype,
BTEqualStrategyNumber);
if (eq_opr == InvalidOid &&
typentry->hash_opf != InvalidOid)
eq_opr = get_opfamily_member(typentry->hash_opf,
typentry->hash_opintype,
typentry->hash_opintype,
HTEqualStrategyNumber);
/*
* If the proposed equality operator is array_eq or record_eq, check
* to see if the element type or column types support equality. If
* not, array_eq or record_eq would fail at runtime, so we don't want
* to report that the type has equality. (We can omit similar
* checking for ranges and multiranges because ranges can't be created
* in the first place unless their subtypes support equality.)
*/
if (eq_opr == ARRAY_EQ_OP &&
!array_element_has_equality(typentry))
eq_opr = InvalidOid;
else if (eq_opr == RECORD_EQ_OP &&
!record_fields_have_equality(typentry))
eq_opr = InvalidOid;
/* Force update of eq_opr_finfo only if we're changing state */
if (typentry->eq_opr != eq_opr)
typentry->eq_opr_finfo.fn_oid = InvalidOid;
typentry->eq_opr = eq_opr;
/*
* Reset info about hash functions whenever we pick up new info about
* equality operator. This is so we can ensure that the hash
* functions match the operator.
*/
typentry->flags &= ~(TCFLAGS_CHECKED_HASH_PROC |
TCFLAGS_CHECKED_HASH_EXTENDED_PROC);
typentry->flags |= TCFLAGS_CHECKED_EQ_OPR;
}
if ((flags & TYPECACHE_LT_OPR) &&
!(typentry->flags & TCFLAGS_CHECKED_LT_OPR))
{
Oid lt_opr = InvalidOid;
if (typentry->btree_opf != InvalidOid)
lt_opr = get_opfamily_member(typentry->btree_opf,
typentry->btree_opintype,
typentry->btree_opintype,
BTLessStrategyNumber);
/*
* As above, make sure array_cmp or record_cmp will succeed; but again
* we need no special check for ranges or multiranges.
*/
if (lt_opr == ARRAY_LT_OP &&
!array_element_has_compare(typentry))
lt_opr = InvalidOid;
else if (lt_opr == RECORD_LT_OP &&
!record_fields_have_compare(typentry))
lt_opr = InvalidOid;
typentry->lt_opr = lt_opr;
typentry->flags |= TCFLAGS_CHECKED_LT_OPR;
}
if ((flags & TYPECACHE_GT_OPR) &&
!(typentry->flags & TCFLAGS_CHECKED_GT_OPR))
{
Oid gt_opr = InvalidOid;
if (typentry->btree_opf != InvalidOid)
gt_opr = get_opfamily_member(typentry->btree_opf,
typentry->btree_opintype,
typentry->btree_opintype,
BTGreaterStrategyNumber);
/*
* As above, make sure array_cmp or record_cmp will succeed; but again
* we need no special check for ranges or multiranges.
*/
if (gt_opr == ARRAY_GT_OP &&
!array_element_has_compare(typentry))
gt_opr = InvalidOid;
else if (gt_opr == RECORD_GT_OP &&
!record_fields_have_compare(typentry))
gt_opr = InvalidOid;
typentry->gt_opr = gt_opr;
typentry->flags |= TCFLAGS_CHECKED_GT_OPR;
}
if ((flags & (TYPECACHE_CMP_PROC | TYPECACHE_CMP_PROC_FINFO)) &&
!(typentry->flags & TCFLAGS_CHECKED_CMP_PROC))
{
Oid cmp_proc = InvalidOid;
if (typentry->btree_opf != InvalidOid)
cmp_proc = get_opfamily_proc(typentry->btree_opf,
typentry->btree_opintype,
typentry->btree_opintype,
BTORDER_PROC);
/*
* As above, make sure array_cmp or record_cmp will succeed; but again
* we need no special check for ranges or multiranges.
*/
if (cmp_proc == F_BTARRAYCMP &&
!array_element_has_compare(typentry))
cmp_proc = InvalidOid;
else if (cmp_proc == F_BTRECORDCMP &&
!record_fields_have_compare(typentry))
cmp_proc = InvalidOid;
/* Force update of cmp_proc_finfo only if we're changing state */
if (typentry->cmp_proc != cmp_proc)
typentry->cmp_proc_finfo.fn_oid = InvalidOid;
typentry->cmp_proc = cmp_proc;
typentry->flags |= TCFLAGS_CHECKED_CMP_PROC;
}
if ((flags & (TYPECACHE_HASH_PROC | TYPECACHE_HASH_PROC_FINFO)) &&
!(typentry->flags & TCFLAGS_CHECKED_HASH_PROC))
{
Oid hash_proc = InvalidOid;
/*
* We insist that the eq_opr, if one has been determined, match the
* hash opclass; else report there is no hash function.
*/
if (typentry->hash_opf != InvalidOid &&
(!OidIsValid(typentry->eq_opr) ||
typentry->eq_opr == get_opfamily_member(typentry->hash_opf,
typentry->hash_opintype,
typentry->hash_opintype,
HTEqualStrategyNumber)))
hash_proc = get_opfamily_proc(typentry->hash_opf,
typentry->hash_opintype,
typentry->hash_opintype,
HASHSTANDARD_PROC);
/*
* As above, make sure hash_array, hash_record, or hash_range will
* succeed.
*/
if (hash_proc == F_HASH_ARRAY &&
!array_element_has_hashing(typentry))
hash_proc = InvalidOid;
else if (hash_proc == F_HASH_RECORD &&
!record_fields_have_hashing(typentry))
hash_proc = InvalidOid;
else if (hash_proc == F_HASH_RANGE &&
!range_element_has_hashing(typentry))
hash_proc = InvalidOid;
/*
* Likewise for hash_multirange.
*/
if (hash_proc == F_HASH_MULTIRANGE &&
!multirange_element_has_hashing(typentry))
hash_proc = InvalidOid;
/* Force update of hash_proc_finfo only if we're changing state */
if (typentry->hash_proc != hash_proc)
typentry->hash_proc_finfo.fn_oid = InvalidOid;
typentry->hash_proc = hash_proc;
typentry->flags |= TCFLAGS_CHECKED_HASH_PROC;
}
if ((flags & (TYPECACHE_HASH_EXTENDED_PROC |
TYPECACHE_HASH_EXTENDED_PROC_FINFO)) &&
!(typentry->flags & TCFLAGS_CHECKED_HASH_EXTENDED_PROC))
{
Oid hash_extended_proc = InvalidOid;
/*
* We insist that the eq_opr, if one has been determined, match the
* hash opclass; else report there is no hash function.
*/
if (typentry->hash_opf != InvalidOid &&
(!OidIsValid(typentry->eq_opr) ||
typentry->eq_opr == get_opfamily_member(typentry->hash_opf,
typentry->hash_opintype,
typentry->hash_opintype,
HTEqualStrategyNumber)))
hash_extended_proc = get_opfamily_proc(typentry->hash_opf,
typentry->hash_opintype,
typentry->hash_opintype,
HASHEXTENDED_PROC);
/*
* As above, make sure hash_array_extended, hash_record_extended, or
* hash_range_extended will succeed.
*/
if (hash_extended_proc == F_HASH_ARRAY_EXTENDED &&
!array_element_has_extended_hashing(typentry))
hash_extended_proc = InvalidOid;
else if (hash_extended_proc == F_HASH_RECORD_EXTENDED &&
!record_fields_have_extended_hashing(typentry))
hash_extended_proc = InvalidOid;
else if (hash_extended_proc == F_HASH_RANGE_EXTENDED &&
!range_element_has_extended_hashing(typentry))
hash_extended_proc = InvalidOid;
/*
* Likewise for hash_multirange_extended.
*/
if (hash_extended_proc == F_HASH_MULTIRANGE_EXTENDED &&
!multirange_element_has_extended_hashing(typentry))
hash_extended_proc = InvalidOid;
/* Force update of proc finfo only if we're changing state */
if (typentry->hash_extended_proc != hash_extended_proc)
typentry->hash_extended_proc_finfo.fn_oid = InvalidOid;
typentry->hash_extended_proc = hash_extended_proc;
typentry->flags |= TCFLAGS_CHECKED_HASH_EXTENDED_PROC;
}
/*
* Set up fmgr lookup info as requested
*
* Note: we tell fmgr the finfo structures live in CacheMemoryContext,
* which is not quite right (they're really in the hash table's private
* memory context) but this will do for our purposes.
*
* Note: the code above avoids invalidating the finfo structs unless the
* referenced operator/function OID actually changes. This is to prevent
* unnecessary leakage of any subsidiary data attached to an finfo, since
* that would cause session-lifespan memory leaks.
*/
if ((flags & TYPECACHE_EQ_OPR_FINFO) &&
typentry->eq_opr_finfo.fn_oid == InvalidOid &&
typentry->eq_opr != InvalidOid)
{
Oid eq_opr_func;
eq_opr_func = get_opcode(typentry->eq_opr);
if (eq_opr_func != InvalidOid)
fmgr_info_cxt(eq_opr_func, &typentry->eq_opr_finfo,
CacheMemoryContext);
}
if ((flags & TYPECACHE_CMP_PROC_FINFO) &&
typentry->cmp_proc_finfo.fn_oid == InvalidOid &&
typentry->cmp_proc != InvalidOid)
{
fmgr_info_cxt(typentry->cmp_proc, &typentry->cmp_proc_finfo,
CacheMemoryContext);
}
if ((flags & TYPECACHE_HASH_PROC_FINFO) &&
typentry->hash_proc_finfo.fn_oid == InvalidOid &&
typentry->hash_proc != InvalidOid)
{
fmgr_info_cxt(typentry->hash_proc, &typentry->hash_proc_finfo,
CacheMemoryContext);
}
if ((flags & TYPECACHE_HASH_EXTENDED_PROC_FINFO) &&
typentry->hash_extended_proc_finfo.fn_oid == InvalidOid &&
typentry->hash_extended_proc != InvalidOid)
{
fmgr_info_cxt(typentry->hash_extended_proc,
&typentry->hash_extended_proc_finfo,
CacheMemoryContext);
}
/*
* If it's a composite type (row type), get tupdesc if requested
*/
if ((flags & TYPECACHE_TUPDESC) &&
typentry->tupDesc == NULL &&
typentry->typtype == TYPTYPE_COMPOSITE)
{
load_typcache_tupdesc(typentry);
}
/*
* If requested, get information about a range type
*
* This includes making sure that the basic info about the range element
* type is up-to-date.
*/
if ((flags & TYPECACHE_RANGE_INFO) &&
typentry->typtype == TYPTYPE_RANGE)
{
if (typentry->rngelemtype == NULL)
load_rangetype_info(typentry);
else if (!(typentry->rngelemtype->flags & TCFLAGS_HAVE_PG_TYPE_DATA))
(void) lookup_type_cache(typentry->rngelemtype->type_id, 0);
}
/*
* If requested, get information about a multirange type
*/
if ((flags & TYPECACHE_MULTIRANGE_INFO) &&
typentry->rngtype == NULL &&
typentry->typtype == TYPTYPE_MULTIRANGE)
{
load_multirangetype_info(typentry);
}
/*
* If requested, get information about a domain type
*/
if ((flags & TYPECACHE_DOMAIN_BASE_INFO) &&
typentry->domainBaseType == InvalidOid &&
typentry->typtype == TYPTYPE_DOMAIN)
{
typentry->domainBaseTypmod = -1;
typentry->domainBaseType =
getBaseTypeAndTypmod(type_id, &typentry->domainBaseTypmod);
}
if ((flags & TYPECACHE_DOMAIN_CONSTR_INFO) &&
(typentry->flags & TCFLAGS_CHECKED_DOMAIN_CONSTRAINTS) == 0 &&
typentry->typtype == TYPTYPE_DOMAIN)
{
load_domaintype_info(typentry);
}
return typentry;
}
/*
* load_typcache_tupdesc --- helper routine to set up composite type's tupDesc
*/
static void
load_typcache_tupdesc(TypeCacheEntry *typentry)
{
Relation rel;
if (!OidIsValid(typentry->typrelid)) /* should not happen */
elog(ERROR, "invalid typrelid for composite type %u",
typentry->type_id);
rel = relation_open(typentry->typrelid, AccessShareLock);
Assert(rel->rd_rel->reltype == typentry->type_id);
/*
* Link to the tupdesc and increment its refcount (we assert it's a
* refcounted descriptor). We don't use IncrTupleDescRefCount() for this,
* because the reference mustn't be entered in the current resource owner;
* it can outlive the current query.
*/
typentry->tupDesc = RelationGetDescr(rel);
Assert(typentry->tupDesc->tdrefcount > 0);
typentry->tupDesc->tdrefcount++;
/*
* In future, we could take some pains to not change tupDesc_identifier if
* the tupdesc didn't really change; but for now it's not worth it.
*/
typentry->tupDesc_identifier = ++tupledesc_id_counter;
relation_close(rel, AccessShareLock);
}
/*
* load_rangetype_info --- helper routine to set up range type information
*/
static void
load_rangetype_info(TypeCacheEntry *typentry)
{
Form_pg_range pg_range;
HeapTuple tup;
Oid subtypeOid;
Oid opclassOid;
Oid canonicalOid;
Oid subdiffOid;
Oid opfamilyOid;
Oid opcintype;
Oid cmpFnOid;
/* get information from pg_range */
tup = SearchSysCache1(RANGETYPE, ObjectIdGetDatum(typentry->type_id));
/* should not fail, since we already checked typtype ... */
if (!HeapTupleIsValid(tup))
elog(ERROR, "cache lookup failed for range type %u",
typentry->type_id);
pg_range = (Form_pg_range) GETSTRUCT(tup);
subtypeOid = pg_range->rngsubtype;
typentry->rng_collation = pg_range->rngcollation;
opclassOid = pg_range->rngsubopc;
canonicalOid = pg_range->rngcanonical;
subdiffOid = pg_range->rngsubdiff;
ReleaseSysCache(tup);
/* get opclass properties and look up the comparison function */
opfamilyOid = get_opclass_family(opclassOid);
opcintype = get_opclass_input_type(opclassOid);
cmpFnOid = get_opfamily_proc(opfamilyOid, opcintype, opcintype,
BTORDER_PROC);
if (!RegProcedureIsValid(cmpFnOid))
elog(ERROR, "missing support function %d(%u,%u) in opfamily %u",
BTORDER_PROC, opcintype, opcintype, opfamilyOid);
/* set up cached fmgrinfo structs */
fmgr_info_cxt(cmpFnOid, &typentry->rng_cmp_proc_finfo,
CacheMemoryContext);
if (OidIsValid(canonicalOid))
fmgr_info_cxt(canonicalOid, &typentry->rng_canonical_finfo,
CacheMemoryContext);
if (OidIsValid(subdiffOid))
fmgr_info_cxt(subdiffOid, &typentry->rng_subdiff_finfo,
CacheMemoryContext);
/* Lastly, set up link to the element type --- this marks data valid */
typentry->rngelemtype = lookup_type_cache(subtypeOid, 0);
}
/*
* load_multirangetype_info --- helper routine to set up multirange type
* information
*/
static void
load_multirangetype_info(TypeCacheEntry *typentry)
{
Oid rangetypeOid;
rangetypeOid = get_multirange_range(typentry->type_id);
if (!OidIsValid(rangetypeOid))
elog(ERROR, "cache lookup failed for multirange type %u",
typentry->type_id);
typentry->rngtype = lookup_type_cache(rangetypeOid, TYPECACHE_RANGE_INFO);
}
/*
* load_domaintype_info --- helper routine to set up domain constraint info
*
* Note: we assume we're called in a relatively short-lived context, so it's
* okay to leak data into the current context while scanning pg_constraint.
* We build the new DomainConstraintCache data in a context underneath
* CurrentMemoryContext, and reparent it under CacheMemoryContext when
* complete.
*/
static void
load_domaintype_info(TypeCacheEntry *typentry)
{
Oid typeOid = typentry->type_id;
DomainConstraintCache *dcc;
bool notNull = false;
DomainConstraintState **ccons;
int cconslen;
Relation conRel;
MemoryContext oldcxt;
/*
* If we're here, any existing constraint info is stale, so release it.
* For safety, be sure to null the link before trying to delete the data.
*/
if (typentry->domainData)
{
dcc = typentry->domainData;
typentry->domainData = NULL;
decr_dcc_refcount(dcc);
}
/*
* We try to optimize the common case of no domain constraints, so don't
* create the dcc object and context until we find a constraint. Likewise
* for the temp sorting array.
*/
dcc = NULL;
ccons = NULL;
cconslen = 0;
/*
* Scan pg_constraint for relevant constraints. We want to find
* constraints for not just this domain, but any ancestor domains, so the
* outer loop crawls up the domain stack.
*/
conRel = table_open(ConstraintRelationId, AccessShareLock);
for (;;)
{
HeapTuple tup;
HeapTuple conTup;
Form_pg_type typTup;
int nccons = 0;
ScanKeyData key[1];
SysScanDesc scan;
tup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typeOid));
if (!HeapTupleIsValid(tup))
elog(ERROR, "cache lookup failed for type %u", typeOid);
typTup = (Form_pg_type) GETSTRUCT(tup);
if (typTup->typtype != TYPTYPE_DOMAIN)
{
/* Not a domain, so done */
ReleaseSysCache(tup);
break;
}
/* Test for NOT NULL Constraint */
if (typTup->typnotnull)
notNull = true;
/* Look for CHECK Constraints on this domain */
ScanKeyInit(&key[0],
Anum_pg_constraint_contypid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(typeOid));
scan = systable_beginscan(conRel, ConstraintTypidIndexId, true,
NULL, 1, key);
while (HeapTupleIsValid(conTup = systable_getnext(scan)))
{
Form_pg_constraint c = (Form_pg_constraint) GETSTRUCT(conTup);
Datum val;
bool isNull;
char *constring;
Expr *check_expr;
DomainConstraintState *r;
/* Ignore non-CHECK constraints (presently, shouldn't be any) */
if (c->contype != CONSTRAINT_CHECK)
continue;
/* Not expecting conbin to be NULL, but we'll test for it anyway */
val = fastgetattr(conTup, Anum_pg_constraint_conbin,
conRel->rd_att, &isNull);
if (isNull)
elog(ERROR, "domain \"%s\" constraint \"%s\" has NULL conbin",
NameStr(typTup->typname), NameStr(c->conname));
/* Convert conbin to C string in caller context */
constring = TextDatumGetCString(val);
/* Create the DomainConstraintCache object and context if needed */
if (dcc == NULL)
{
MemoryContext cxt;
cxt = AllocSetContextCreate(CurrentMemoryContext,
"Domain constraints",
ALLOCSET_SMALL_SIZES);
dcc = (DomainConstraintCache *)
MemoryContextAlloc(cxt, sizeof(DomainConstraintCache));
dcc->constraints = NIL;
dcc->dccContext = cxt;
dcc->dccRefCount = 0;
}
/* Create node trees in DomainConstraintCache's context */
oldcxt = MemoryContextSwitchTo(dcc->dccContext);
check_expr = (Expr *) stringToNode(constring);
/*
* Plan the expression, since ExecInitExpr will expect that.
*
* Note: caching the result of expression_planner() is not very
* good practice. Ideally we'd use a CachedExpression here so
* that we would react promptly to, eg, changes in inlined
* functions. However, because we don't support mutable domain
* CHECK constraints, it's not really clear that it's worth the
* extra overhead to do that.
*/
check_expr = expression_planner(check_expr);
r = makeNode(DomainConstraintState);
r->constrainttype = DOM_CONSTRAINT_CHECK;
r->name = pstrdup(NameStr(c->conname));
r->check_expr = check_expr;
r->check_exprstate = NULL;
MemoryContextSwitchTo(oldcxt);
/* Accumulate constraints in an array, for sorting below */
if (ccons == NULL)
{
cconslen = 8;
ccons = (DomainConstraintState **)
palloc(cconslen * sizeof(DomainConstraintState *));
}
else if (nccons >= cconslen)
{
cconslen *= 2;
ccons = (DomainConstraintState **)
repalloc(ccons, cconslen * sizeof(DomainConstraintState *));
}
ccons[nccons++] = r;
}
systable_endscan(scan);
if (nccons > 0)
{
/*
* Sort the items for this domain, so that CHECKs are applied in a
* deterministic order.
*/
if (nccons > 1)
qsort(ccons, nccons, sizeof(DomainConstraintState *), dcs_cmp);
/*
* Now attach them to the overall list. Use lcons() here because
* constraints of parent domains should be applied earlier.
*/
oldcxt = MemoryContextSwitchTo(dcc->dccContext);
while (nccons > 0)
dcc->constraints = lcons(ccons[--nccons], dcc->constraints);
MemoryContextSwitchTo(oldcxt);
}
/* loop to next domain in stack */
typeOid = typTup->typbasetype;
ReleaseSysCache(tup);
}
table_close(conRel, AccessShareLock);
/*
* Only need to add one NOT NULL check regardless of how many domains in
* the stack request it.
*/
if (notNull)
{
DomainConstraintState *r;
/* Create the DomainConstraintCache object and context if needed */
if (dcc == NULL)
{
MemoryContext cxt;
cxt = AllocSetContextCreate(CurrentMemoryContext,
"Domain constraints",
ALLOCSET_SMALL_SIZES);
dcc = (DomainConstraintCache *)
MemoryContextAlloc(cxt, sizeof(DomainConstraintCache));
dcc->constraints = NIL;
dcc->dccContext = cxt;
dcc->dccRefCount = 0;
}
/* Create node trees in DomainConstraintCache's context */
oldcxt = MemoryContextSwitchTo(dcc->dccContext);
r = makeNode(DomainConstraintState);
r->constrainttype = DOM_CONSTRAINT_NOTNULL;
r->name = pstrdup("NOT NULL");
r->check_expr = NULL;
r->check_exprstate = NULL;
/* lcons to apply the nullness check FIRST */
dcc->constraints = lcons(r, dcc->constraints);
MemoryContextSwitchTo(oldcxt);
}
/*
* If we made a constraint object, move it into CacheMemoryContext and
* attach it to the typcache entry.
*/
if (dcc)
{
MemoryContextSetParent(dcc->dccContext, CacheMemoryContext);
typentry->domainData = dcc;
dcc->dccRefCount++; /* count the typcache's reference */
}
/* Either way, the typcache entry's domain data is now valid. */
typentry->flags |= TCFLAGS_CHECKED_DOMAIN_CONSTRAINTS;
}
/*
* qsort comparator to sort DomainConstraintState pointers by name
*/
static int
dcs_cmp(const void *a, const void *b)
{
const DomainConstraintState *const *ca = (const DomainConstraintState *const *) a;
const DomainConstraintState *const *cb = (const DomainConstraintState *const *) b;
return strcmp((*ca)->name, (*cb)->name);
}
/*
* decr_dcc_refcount --- decrement a DomainConstraintCache's refcount,
* and free it if no references remain
*/
static void
decr_dcc_refcount(DomainConstraintCache *dcc)
{
Assert(dcc->dccRefCount > 0);
if (--(dcc->dccRefCount) <= 0)
MemoryContextDelete(dcc->dccContext);
}
/*
* Context reset/delete callback for a DomainConstraintRef
*/
static void
dccref_deletion_callback(void *arg)
{
DomainConstraintRef *ref = (DomainConstraintRef *) arg;
DomainConstraintCache *dcc = ref->dcc;
/* Paranoia --- be sure link is nulled before trying to release */
if (dcc)
{
ref->constraints = NIL;
ref->dcc = NULL;
decr_dcc_refcount(dcc);
}
}
/*
* prep_domain_constraints --- prepare domain constraints for execution
*
* The expression trees stored in the DomainConstraintCache's list are
* converted to executable expression state trees stored in execctx.
*/
static List *
prep_domain_constraints(List *constraints, MemoryContext execctx)
{
List *result = NIL;
MemoryContext oldcxt;
ListCell *lc;
oldcxt = MemoryContextSwitchTo(execctx);
foreach(lc, constraints)
{
DomainConstraintState *r = (DomainConstraintState *) lfirst(lc);
DomainConstraintState *newr;
newr = makeNode(DomainConstraintState);
newr->constrainttype = r->constrainttype;
newr->name = r->name;
newr->check_expr = r->check_expr;
newr->check_exprstate = ExecInitExpr(r->check_expr, NULL);
result = lappend(result, newr);
}
MemoryContextSwitchTo(oldcxt);
return result;
}
/*
* InitDomainConstraintRef --- initialize a DomainConstraintRef struct
*
* Caller must tell us the MemoryContext in which the DomainConstraintRef
* lives. The ref will be cleaned up when that context is reset/deleted.
*
* Caller must also tell us whether it wants check_exprstate fields to be
* computed in the DomainConstraintState nodes attached to this ref.
* If it doesn't, we need not make a copy of the DomainConstraintState list.
*/
void
InitDomainConstraintRef(Oid type_id, DomainConstraintRef *ref,
MemoryContext refctx, bool need_exprstate)
{
/* Look up the typcache entry --- we assume it survives indefinitely */
ref->tcache = lookup_type_cache(type_id, TYPECACHE_DOMAIN_CONSTR_INFO);
ref->need_exprstate = need_exprstate;
/* For safety, establish the callback before acquiring a refcount */
ref->refctx = refctx;
ref->dcc = NULL;
ref->callback.func = dccref_deletion_callback;
ref->callback.arg = (void *) ref;
MemoryContextRegisterResetCallback(refctx, &ref->callback);
/* Acquire refcount if there are constraints, and set up exported list */
if (ref->tcache->domainData)
{
ref->dcc = ref->tcache->domainData;
ref->dcc->dccRefCount++;
if (ref->need_exprstate)
ref->constraints = prep_domain_constraints(ref->dcc->constraints,
ref->refctx);
else
ref->constraints = ref->dcc->constraints;
}
else
ref->constraints = NIL;
}
/*
* UpdateDomainConstraintRef --- recheck validity of domain constraint info
*
* If the domain's constraint set changed, ref->constraints is updated to
* point at a new list of cached constraints.
*
* In the normal case where nothing happened to the domain, this is cheap
* enough that it's reasonable (and expected) to check before *each* use
* of the constraint info.
*/
void
UpdateDomainConstraintRef(DomainConstraintRef *ref)
{
TypeCacheEntry *typentry = ref->tcache;
/* Make sure typcache entry's data is up to date */
if ((typentry->flags & TCFLAGS_CHECKED_DOMAIN_CONSTRAINTS) == 0 &&
typentry->typtype == TYPTYPE_DOMAIN)
load_domaintype_info(typentry);
/* Transfer to ref object if there's new info, adjusting refcounts */
if (ref->dcc != typentry->domainData)
{
/* Paranoia --- be sure link is nulled before trying to release */
DomainConstraintCache *dcc = ref->dcc;
if (dcc)
{
/*
* Note: we just leak the previous list of executable domain
* constraints. Alternatively, we could keep those in a child
* context of ref->refctx and free that context at this point.
* However, in practice this code path will be taken so seldom
* that the extra bookkeeping for a child context doesn't seem
* worthwhile; we'll just allow a leak for the lifespan of refctx.
*/
ref->constraints = NIL;
ref->dcc = NULL;
decr_dcc_refcount(dcc);
}
dcc = typentry->domainData;
if (dcc)
{
ref->dcc = dcc;
dcc->dccRefCount++;
if (ref->need_exprstate)
ref->constraints = prep_domain_constraints(dcc->constraints,
ref->refctx);
else
ref->constraints = dcc->constraints;
}
}
}
/*
* DomainHasConstraints --- utility routine to check if a domain has constraints
*
* This is defined to return false, not fail, if type is not a domain.
*/
bool
DomainHasConstraints(Oid type_id)
{
TypeCacheEntry *typentry;
/*
* Note: a side effect is to cause the typcache's domain data to become
* valid. This is fine since we'll likely need it soon if there is any.
*/
typentry = lookup_type_cache(type_id, TYPECACHE_DOMAIN_CONSTR_INFO);
return (typentry->domainData != NULL);
}
/*
* array_element_has_equality and friends are helper routines to check
* whether we should believe that array_eq and related functions will work
* on the given array type or composite type.
*
* The logic above may call these repeatedly on the same type entry, so we
* make use of the typentry->flags field to cache the results once known.
* Also, we assume that we'll probably want all these facts about the type
* if we want any, so we cache them all using only one lookup of the
* component datatype(s).
*/
static bool
array_element_has_equality(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_ELEM_PROPERTIES))
cache_array_element_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_ELEM_EQUALITY) != 0;
}
static bool
array_element_has_compare(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_ELEM_PROPERTIES))
cache_array_element_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_ELEM_COMPARE) != 0;
}
static bool
array_element_has_hashing(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_ELEM_PROPERTIES))
cache_array_element_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_ELEM_HASHING) != 0;
}
static bool
array_element_has_extended_hashing(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_ELEM_PROPERTIES))
cache_array_element_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_ELEM_EXTENDED_HASHING) != 0;
}
static void
cache_array_element_properties(TypeCacheEntry *typentry)
{
Oid elem_type = get_base_element_type(typentry->type_id);
if (OidIsValid(elem_type))
{
TypeCacheEntry *elementry;
elementry = lookup_type_cache(elem_type,
TYPECACHE_EQ_OPR |
TYPECACHE_CMP_PROC |
TYPECACHE_HASH_PROC |
TYPECACHE_HASH_EXTENDED_PROC);
if (OidIsValid(elementry->eq_opr))
typentry->flags |= TCFLAGS_HAVE_ELEM_EQUALITY;
if (OidIsValid(elementry->cmp_proc))
typentry->flags |= TCFLAGS_HAVE_ELEM_COMPARE;
if (OidIsValid(elementry->hash_proc))
typentry->flags |= TCFLAGS_HAVE_ELEM_HASHING;
if (OidIsValid(elementry->hash_extended_proc))
typentry->flags |= TCFLAGS_HAVE_ELEM_EXTENDED_HASHING;
}
typentry->flags |= TCFLAGS_CHECKED_ELEM_PROPERTIES;
}
/*
* Likewise, some helper functions for composite types.
*/
static bool
record_fields_have_equality(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_FIELD_PROPERTIES))
cache_record_field_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_FIELD_EQUALITY) != 0;
}
static bool
record_fields_have_compare(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_FIELD_PROPERTIES))
cache_record_field_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_FIELD_COMPARE) != 0;
}
static bool
record_fields_have_hashing(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_FIELD_PROPERTIES))
cache_record_field_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_FIELD_HASHING) != 0;
}
static bool
record_fields_have_extended_hashing(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_FIELD_PROPERTIES))
cache_record_field_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_FIELD_EXTENDED_HASHING) != 0;
}
static void
cache_record_field_properties(TypeCacheEntry *typentry)
{
/*
* For type RECORD, we can't really tell what will work, since we don't
* have access here to the specific anonymous type. Just assume that
* equality and comparison will (we may get a failure at runtime). We
* could also claim that hashing works, but then if code that has the
* option between a comparison-based (sort-based) and a hash-based plan
* chooses hashing, stuff could fail that would otherwise work if it chose
* a comparison-based plan. In practice more types support comparison
* than hashing.
*/
if (typentry->type_id == RECORDOID)
{
typentry->flags |= (TCFLAGS_HAVE_FIELD_EQUALITY |
TCFLAGS_HAVE_FIELD_COMPARE);
}
else if (typentry->typtype == TYPTYPE_COMPOSITE)
{
TupleDesc tupdesc;
int newflags;
int i;
/* Fetch composite type's tupdesc if we don't have it already */
if (typentry->tupDesc == NULL)
load_typcache_tupdesc(typentry);
tupdesc = typentry->tupDesc;
/* Must bump the refcount while we do additional catalog lookups */
IncrTupleDescRefCount(tupdesc);
/* Have each property if all non-dropped fields have the property */
newflags = (TCFLAGS_HAVE_FIELD_EQUALITY |
TCFLAGS_HAVE_FIELD_COMPARE |
TCFLAGS_HAVE_FIELD_HASHING |
TCFLAGS_HAVE_FIELD_EXTENDED_HASHING);
for (i = 0; i < tupdesc->natts; i++)
{
TypeCacheEntry *fieldentry;
Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
if (attr->attisdropped)
continue;
fieldentry = lookup_type_cache(attr->atttypid,
TYPECACHE_EQ_OPR |
TYPECACHE_CMP_PROC |
TYPECACHE_HASH_PROC |
TYPECACHE_HASH_EXTENDED_PROC);
if (!OidIsValid(fieldentry->eq_opr))
newflags &= ~TCFLAGS_HAVE_FIELD_EQUALITY;
if (!OidIsValid(fieldentry->cmp_proc))
newflags &= ~TCFLAGS_HAVE_FIELD_COMPARE;
if (!OidIsValid(fieldentry->hash_proc))
newflags &= ~TCFLAGS_HAVE_FIELD_HASHING;
if (!OidIsValid(fieldentry->hash_extended_proc))
newflags &= ~TCFLAGS_HAVE_FIELD_EXTENDED_HASHING;
/* We can drop out of the loop once we disprove all bits */
if (newflags == 0)
break;
}
typentry->flags |= newflags;
DecrTupleDescRefCount(tupdesc);
}
else if (typentry->typtype == TYPTYPE_DOMAIN)
{
/* If it's domain over composite, copy base type's properties */
TypeCacheEntry *baseentry;
/* load up basetype info if we didn't already */
if (typentry->domainBaseType == InvalidOid)
{
typentry->domainBaseTypmod = -1;
typentry->domainBaseType =
getBaseTypeAndTypmod(typentry->type_id,
&typentry->domainBaseTypmod);
}
baseentry = lookup_type_cache(typentry->domainBaseType,
TYPECACHE_EQ_OPR |
TYPECACHE_CMP_PROC |
TYPECACHE_HASH_PROC |
TYPECACHE_HASH_EXTENDED_PROC);
if (baseentry->typtype == TYPTYPE_COMPOSITE)
{
typentry->flags |= TCFLAGS_DOMAIN_BASE_IS_COMPOSITE;
typentry->flags |= baseentry->flags & (TCFLAGS_HAVE_FIELD_EQUALITY |
TCFLAGS_HAVE_FIELD_COMPARE |
TCFLAGS_HAVE_FIELD_HASHING |
TCFLAGS_HAVE_FIELD_EXTENDED_HASHING);
}
}
typentry->flags |= TCFLAGS_CHECKED_FIELD_PROPERTIES;
}
/*
* Likewise, some helper functions for range and multirange types.
*
* We can borrow the flag bits for array element properties to use for range
* element properties, since those flag bits otherwise have no use in a
* range or multirange type's typcache entry.
*/
static bool
range_element_has_hashing(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_ELEM_PROPERTIES))
cache_range_element_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_ELEM_HASHING) != 0;
}
static bool
range_element_has_extended_hashing(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_ELEM_PROPERTIES))
cache_range_element_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_ELEM_EXTENDED_HASHING) != 0;
}
static void
cache_range_element_properties(TypeCacheEntry *typentry)
{
/* load up subtype link if we didn't already */
if (typentry->rngelemtype == NULL &&
typentry->typtype == TYPTYPE_RANGE)
load_rangetype_info(typentry);
if (typentry->rngelemtype != NULL)
{
TypeCacheEntry *elementry;
/* might need to calculate subtype's hash function properties */
elementry = lookup_type_cache(typentry->rngelemtype->type_id,
TYPECACHE_HASH_PROC |
TYPECACHE_HASH_EXTENDED_PROC);
if (OidIsValid(elementry->hash_proc))
typentry->flags |= TCFLAGS_HAVE_ELEM_HASHING;
if (OidIsValid(elementry->hash_extended_proc))
typentry->flags |= TCFLAGS_HAVE_ELEM_EXTENDED_HASHING;
}
typentry->flags |= TCFLAGS_CHECKED_ELEM_PROPERTIES;
}
static bool
multirange_element_has_hashing(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_ELEM_PROPERTIES))
cache_multirange_element_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_ELEM_HASHING) != 0;
}
static bool
multirange_element_has_extended_hashing(TypeCacheEntry *typentry)
{
if (!(typentry->flags & TCFLAGS_CHECKED_ELEM_PROPERTIES))
cache_multirange_element_properties(typentry);
return (typentry->flags & TCFLAGS_HAVE_ELEM_EXTENDED_HASHING) != 0;
}
static void
cache_multirange_element_properties(TypeCacheEntry *typentry)
{
/* load up range link if we didn't already */
if (typentry->rngtype == NULL &&
typentry->typtype == TYPTYPE_MULTIRANGE)
load_multirangetype_info(typentry);
if (typentry->rngtype != NULL && typentry->rngtype->rngelemtype != NULL)
{
TypeCacheEntry *elementry;
/* might need to calculate subtype's hash function properties */
elementry = lookup_type_cache(typentry->rngtype->rngelemtype->type_id,
TYPECACHE_HASH_PROC |
TYPECACHE_HASH_EXTENDED_PROC);
if (OidIsValid(elementry->hash_proc))
typentry->flags |= TCFLAGS_HAVE_ELEM_HASHING;
if (OidIsValid(elementry->hash_extended_proc))
typentry->flags |= TCFLAGS_HAVE_ELEM_EXTENDED_HASHING;
}
typentry->flags |= TCFLAGS_CHECKED_ELEM_PROPERTIES;
}
/*
* Make sure that RecordCacheArray and RecordIdentifierArray are large enough
* to store 'typmod'.
*/
static void
ensure_record_cache_typmod_slot_exists(int32 typmod)
{
if (RecordCacheArray == NULL)
{
RecordCacheArray = (TupleDesc *)
MemoryContextAllocZero(CacheMemoryContext, 64 * sizeof(TupleDesc));
RecordIdentifierArray = (uint64 *)
MemoryContextAllocZero(CacheMemoryContext, 64 * sizeof(uint64));
RecordCacheArrayLen = 64;
}
if (typmod >= RecordCacheArrayLen)
{
int32 newlen = RecordCacheArrayLen * 2;
while (typmod >= newlen)
newlen *= 2;
RecordCacheArray = (TupleDesc *) repalloc(RecordCacheArray,
newlen * sizeof(TupleDesc));
memset(RecordCacheArray + RecordCacheArrayLen, 0,
(newlen - RecordCacheArrayLen) * sizeof(TupleDesc));
RecordIdentifierArray = (uint64 *) repalloc(RecordIdentifierArray,
newlen * sizeof(uint64));
memset(RecordIdentifierArray + RecordCacheArrayLen, 0,
(newlen - RecordCacheArrayLen) * sizeof(uint64));
RecordCacheArrayLen = newlen;
}
}
/*
* lookup_rowtype_tupdesc_internal --- internal routine to lookup a rowtype
*
* Same API as lookup_rowtype_tupdesc_noerror, but the returned tupdesc
* hasn't had its refcount bumped.
*/
static TupleDesc
lookup_rowtype_tupdesc_internal(Oid type_id, int32 typmod, bool noError)
{
if (type_id != RECORDOID)
{
/*
* It's a named composite type, so use the regular typcache.
*/
TypeCacheEntry *typentry;
typentry = lookup_type_cache(type_id, TYPECACHE_TUPDESC);
if (typentry->tupDesc == NULL && !noError)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("type %s is not composite",
format_type_be(type_id))));
return typentry->tupDesc;
}
else
{
/*
* It's a transient record type, so look in our record-type table.
*/
if (typmod >= 0)
{
/* It is already in our local cache? */
if (typmod < RecordCacheArrayLen &&
RecordCacheArray[typmod] != NULL)
return RecordCacheArray[typmod];
/* Are we attached to a shared record typmod registry? */
if (CurrentSession->shared_typmod_registry != NULL)
{
SharedTypmodTableEntry *entry;
/* Try to find it in the shared typmod index. */
entry = dshash_find(CurrentSession->shared_typmod_table,
&typmod, false);
if (entry != NULL)
{
TupleDesc tupdesc;
tupdesc = (TupleDesc)
dsa_get_address(CurrentSession->area,
entry->shared_tupdesc);
Assert(typmod == tupdesc->tdtypmod);
/* We may need to extend the local RecordCacheArray. */
ensure_record_cache_typmod_slot_exists(typmod);
/*
* Our local array can now point directly to the TupleDesc
* in shared memory, which is non-reference-counted.
*/
RecordCacheArray[typmod] = tupdesc;
Assert(tupdesc->tdrefcount == -1);
/*
* We don't share tupdesc identifiers across processes, so
* assign one locally.
*/
RecordIdentifierArray[typmod] = ++tupledesc_id_counter;
dshash_release_lock(CurrentSession->shared_typmod_table,
entry);
return RecordCacheArray[typmod];
}
}
}
if (!noError)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("record type has not been registered")));
return NULL;
}
}
/*
* lookup_rowtype_tupdesc
*
* Given a typeid/typmod that should describe a known composite type,
* return the tuple descriptor for the type. Will ereport on failure.
* (Use ereport because this is reachable with user-specified OIDs,
* for example from record_in().)
*
* Note: on success, we increment the refcount of the returned TupleDesc,
* and log the reference in CurrentResourceOwner. Caller should call
* ReleaseTupleDesc or DecrTupleDescRefCount when done using the tupdesc.
*/
TupleDesc
lookup_rowtype_tupdesc(Oid type_id, int32 typmod)
{
TupleDesc tupDesc;
tupDesc = lookup_rowtype_tupdesc_internal(type_id, typmod, false);
PinTupleDesc(tupDesc);
return tupDesc;
}
/*
* lookup_rowtype_tupdesc_noerror
*
* As above, but if the type is not a known composite type and noError
* is true, returns NULL instead of ereport'ing. (Note that if a bogus
* type_id is passed, you'll get an ereport anyway.)
*/
TupleDesc
lookup_rowtype_tupdesc_noerror(Oid type_id, int32 typmod, bool noError)
{
TupleDesc tupDesc;
tupDesc = lookup_rowtype_tupdesc_internal(type_id, typmod, noError);
if (tupDesc != NULL)
PinTupleDesc(tupDesc);
return tupDesc;
}
/*
* lookup_rowtype_tupdesc_copy
*
* Like lookup_rowtype_tupdesc(), but the returned TupleDesc has been
* copied into the CurrentMemoryContext and is not reference-counted.
*/
TupleDesc
lookup_rowtype_tupdesc_copy(Oid type_id, int32 typmod)
{
TupleDesc tmp;
tmp = lookup_rowtype_tupdesc_internal(type_id, typmod, false);
return CreateTupleDescCopyConstr(tmp);
}
/*
* lookup_rowtype_tupdesc_domain
*
* Same as lookup_rowtype_tupdesc_noerror(), except that the type can also be
* a domain over a named composite type; so this is effectively equivalent to
* lookup_rowtype_tupdesc_noerror(getBaseType(type_id), typmod, noError)
* except for being a tad faster.
*
* Note: the reason we don't fold the look-through-domain behavior into plain
* lookup_rowtype_tupdesc() is that we want callers to know they might be
* dealing with a domain. Otherwise they might construct a tuple that should
* be of the domain type, but not apply domain constraints.
*/
TupleDesc
lookup_rowtype_tupdesc_domain(Oid type_id, int32 typmod, bool noError)
{
TupleDesc tupDesc;
if (type_id != RECORDOID)
{
/*
* Check for domain or named composite type. We might as well load
* whichever data is needed.
*/
TypeCacheEntry *typentry;
typentry = lookup_type_cache(type_id,
TYPECACHE_TUPDESC |
TYPECACHE_DOMAIN_BASE_INFO);
if (typentry->typtype == TYPTYPE_DOMAIN)
return lookup_rowtype_tupdesc_noerror(typentry->domainBaseType,
typentry->domainBaseTypmod,
noError);
if (typentry->tupDesc == NULL && !noError)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("type %s is not composite",
format_type_be(type_id))));
tupDesc = typentry->tupDesc;
}
else
tupDesc = lookup_rowtype_tupdesc_internal(type_id, typmod, noError);
if (tupDesc != NULL)
PinTupleDesc(tupDesc);
return tupDesc;
}
/*
* GPDB: In order to reuse the retrieve conn for different endpoints,
* it is necessary to detach from the old session DSM segment during
* start_retrieve(), which will invalidate the record cache. The record
* cache of the retrieve connection is a pointer to the shared memory
* segment, so we can directly reset the RecordCacheArray.
*/
void
reset_record_cache(void)
{
if (RecordCacheArray != NULL)
{
Assert(RecordCacheArrayLen != 0);
Assert(RecordIdentifierArray != NULL);
pfree(RecordCacheArray);
pfree(RecordIdentifierArray);
RecordCacheArray = NULL;
RecordIdentifierArray = NULL;
RecordCacheArrayLen = 0;
}
}
/*
* Hash function for the hash table of RecordCacheEntry.
*/
static uint32
record_type_typmod_hash(const void *data, size_t size)
{
RecordCacheEntry *entry = (RecordCacheEntry *) data;
return hashTupleDesc(entry->tupdesc);
}
/*
* Match function for the hash table of RecordCacheEntry.
*/
static int
record_type_typmod_compare(const void *a, const void *b, size_t size)
{
RecordCacheEntry *left = (RecordCacheEntry *) a;
RecordCacheEntry *right = (RecordCacheEntry *) b;
return equalTupleDescs(left->tupdesc, right->tupdesc, true) ? 0 : 1;
}
/*
* assign_record_type_typmod
*
* Given a tuple descriptor for a RECORD type, find or create a cache entry
* for the type, and set the tupdesc's tdtypmod field to a value that will
* identify this cache entry to lookup_rowtype_tupdesc.
*/
void
assign_record_type_typmod(TupleDesc tupDesc)
{
RecordCacheEntry *recentry;
TupleDesc entDesc;
bool found;
MemoryContext oldcxt;
Assert(tupDesc->tdtypeid == RECORDOID);
if (RecordCacheHash == NULL)
{
/* First time through: initialize the hash table */
HASHCTL ctl;
ctl.keysize = sizeof(TupleDesc); /* just the pointer */
ctl.entrysize = sizeof(RecordCacheEntry);
ctl.hash = record_type_typmod_hash;
ctl.match = record_type_typmod_compare;
RecordCacheHash = hash_create("Record information cache", 64,
&ctl,
HASH_ELEM | HASH_FUNCTION | HASH_COMPARE);
/* Also make sure CacheMemoryContext exists */
if (!CacheMemoryContext)
CreateCacheMemoryContext();
}
/*
* Find a hashtable entry for this tuple descriptor. We don't use
* HASH_ENTER yet, because if it's missing, we need to make sure that all
* the allocations succeed before we create the new entry.
*/
recentry = (RecordCacheEntry *) hash_search(RecordCacheHash,
(void *) &tupDesc,
HASH_FIND, &found);
if (found && recentry->tupdesc != NULL)
{
tupDesc->tdtypmod = recentry->tupdesc->tdtypmod;
return;
}
/* Not present, so need to manufacture an entry */
oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
/* Look in the SharedRecordTypmodRegistry, if attached */
entDesc = find_or_make_matching_shared_tupledesc(tupDesc);
if (entDesc == NULL)
{
/*
* Make sure we have room before we CreateTupleDescCopy() or advance
* NextRecordTypmod.
*/
ensure_record_cache_typmod_slot_exists(NextRecordTypmod);
/* Reference-counted local cache only. */
entDesc = CreateTupleDescCopy(tupDesc);
entDesc->tdrefcount = 1;
entDesc->tdtypmod = NextRecordTypmod++;
}
else
{
ensure_record_cache_typmod_slot_exists(entDesc->tdtypmod);
}
RecordCacheArray[entDesc->tdtypmod] = entDesc;
/* Assign a unique tupdesc identifier, too. */
RecordIdentifierArray[entDesc->tdtypmod] = ++tupledesc_id_counter;
/* Fully initialized; create the hash table entry */
recentry = (RecordCacheEntry *) hash_search(RecordCacheHash,
(void *) &tupDesc,
HASH_ENTER, NULL);
recentry->tupdesc = entDesc;
/* Update the caller's tuple descriptor. */
tupDesc->tdtypmod = entDesc->tdtypmod;
MemoryContextSwitchTo(oldcxt);
}
/*
* assign_record_type_identifier
*
* Get an identifier, which will be unique over the lifespan of this backend
* process, for the current tuple descriptor of the specified composite type.
* For named composite types, the value is guaranteed to change if the type's
* definition does. For registered RECORD types, the value will not change
* once assigned, since the registered type won't either. If an anonymous
* RECORD type is specified, we return a new identifier on each call.
*/
uint64
assign_record_type_identifier(Oid type_id, int32 typmod)
{
if (type_id != RECORDOID)
{
/*
* It's a named composite type, so use the regular typcache.
*/
TypeCacheEntry *typentry;
typentry = lookup_type_cache(type_id, TYPECACHE_TUPDESC);
if (typentry->tupDesc == NULL)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("type %s is not composite",
format_type_be(type_id))));
Assert(typentry->tupDesc_identifier != 0);
return typentry->tupDesc_identifier;
}
else
{
/*
* It's a transient record type, so look in our record-type table.
*/
if (typmod >= 0 && typmod < RecordCacheArrayLen &&
RecordCacheArray[typmod] != NULL)
{
Assert(RecordIdentifierArray[typmod] != 0);
return RecordIdentifierArray[typmod];
}
/* For anonymous or unrecognized record type, generate a new ID */
return ++tupledesc_id_counter;
}
}
/*
* Return the amount of shmem required to hold a SharedRecordTypmodRegistry.
* This exists only to avoid exposing private innards of
* SharedRecordTypmodRegistry in a header.
*/
size_t
SharedRecordTypmodRegistryEstimate(void)
{
return sizeof(SharedRecordTypmodRegistry);
}
/*
* Return the next typmod from shared registry.
*/
uint32
GetSharedNextRecordTypmod(SharedRecordTypmodRegistry* registry)
{
return pg_atomic_read_u32(&registry->next_typmod);
}
/*
* Initialize 'registry' in a pre-existing shared memory region, which must be
* maximally aligned and have space for SharedRecordTypmodRegistryEstimate()
* bytes.
*
* 'area' will be used to allocate shared memory space as required for the
* typemod registration. The current process, expected to be a leader process
* in a parallel query, will be attached automatically and its current record
* types will be loaded into *registry. While attached, all calls to
* assign_record_type_typmod will use the shared registry. Worker backends
* will need to attach explicitly.
*
* Note that this function takes 'area' and 'segment' as arguments rather than
* accessing them via CurrentSession, because they aren't installed there
* until after this function runs.
*/
void
SharedRecordTypmodRegistryInit(SharedRecordTypmodRegistry *registry,
dsm_segment *segment,
dsa_area *area)
{
MemoryContext old_context;
dshash_table *record_table;
dshash_table *typmod_table;
int32 typmod;
Assert(!IsParallelWorker());
/* We can't already be attached to a shared registry. */
Assert(CurrentSession->shared_typmod_registry == NULL);
Assert(CurrentSession->shared_record_table == NULL);
Assert(CurrentSession->shared_typmod_table == NULL);
old_context = MemoryContextSwitchTo(TopMemoryContext);
/* Create the hash table of tuple descriptors indexed by themselves. */
record_table = dshash_create(area, &srtr_record_table_params, area);
/* Create the hash table of tuple descriptors indexed by typmod. */
typmod_table = dshash_create(area, &srtr_typmod_table_params, NULL);
MemoryContextSwitchTo(old_context);
/* Initialize the SharedRecordTypmodRegistry. */
registry->record_table_handle = dshash_get_hash_table_handle(record_table);
registry->typmod_table_handle = dshash_get_hash_table_handle(typmod_table);
pg_atomic_init_u32(&registry->next_typmod, NextRecordTypmod);
/*
* Copy all entries from this backend's private registry into the shared
* registry.
*/
for (typmod = 0; typmod < NextRecordTypmod; ++typmod)
{
SharedTypmodTableEntry *typmod_table_entry;
SharedRecordTableEntry *record_table_entry;
SharedRecordTableKey record_table_key;
dsa_pointer shared_dp;
TupleDesc tupdesc;
bool found;
tupdesc = RecordCacheArray[typmod];
if (tupdesc == NULL)
continue;
/* Copy the TupleDesc into shared memory. */
shared_dp = share_tupledesc(area, tupdesc, typmod);
/* Insert into the typmod table. */
typmod_table_entry = dshash_find_or_insert(typmod_table,
&tupdesc->tdtypmod,
&found);
if (found)
elog(ERROR, "cannot create duplicate shared record typmod");
typmod_table_entry->typmod = tupdesc->tdtypmod;
typmod_table_entry->shared_tupdesc = shared_dp;
dshash_release_lock(typmod_table, typmod_table_entry);
/* Insert into the record table. */
record_table_key.shared = false;
record_table_key.u.local_tupdesc = tupdesc;
record_table_entry = dshash_find_or_insert(record_table,
&record_table_key,
&found);
if (!found)
{
record_table_entry->key.shared = true;
record_table_entry->key.u.shared_tupdesc = shared_dp;
}
dshash_release_lock(record_table, record_table_entry);
}
/*
* Set up the global state that will tell assign_record_type_typmod and
* lookup_rowtype_tupdesc_internal about the shared registry.
*/
CurrentSession->shared_record_table = record_table;
CurrentSession->shared_typmod_table = typmod_table;
CurrentSession->shared_typmod_registry = registry;
/*
* We install a detach hook in the leader, but only to handle cleanup on
* failure during GetSessionDsmHandle(). Once GetSessionDsmHandle() pins
* the memory, the leader process will use a shared registry until it
* exits.
*/
on_dsm_detach(segment, shared_record_typmod_registry_detach, (Datum) 0);
}
/*
* Attach to 'registry', which must have been initialized already by another
* backend. Future calls to assign_record_type_typmod and
* lookup_rowtype_tupdesc_internal will use the shared registry until the
* current session is detached.
*/
void
SharedRecordTypmodRegistryAttach(SharedRecordTypmodRegistry *registry)
{
MemoryContext old_context;
dshash_table *record_table;
dshash_table *typmod_table;
/*
* gpdb: comment this line out since we use this function for parallel
* retrieve cursor also while upstream uses this for parallel work only.
*/
#if 0
Assert(IsParallelWorker());
#endif
/* We can't already be attached to a shared registry. */
Assert(CurrentSession != NULL);
Assert(CurrentSession->segment != NULL);
Assert(CurrentSession->area != NULL);
Assert(CurrentSession->shared_typmod_registry == NULL);
Assert(CurrentSession->shared_record_table == NULL);
Assert(CurrentSession->shared_typmod_table == NULL);
/*
* We can't already have typmods in our local cache, because they'd clash
* with those imported by SharedRecordTypmodRegistryInit. This should be
* a freshly started parallel worker. If we ever support worker
* recycling, a worker would need to zap its local cache in between
* servicing different queries, in order to be able to call this and
* synchronize typmods with a new leader; but that's problematic because
* we can't be very sure that record-typmod-related state hasn't escaped
* to anywhere else in the process.
*/
Assert(NextRecordTypmod == 0);
old_context = MemoryContextSwitchTo(TopMemoryContext);
/* Attach to the two hash tables. */
record_table = dshash_attach(CurrentSession->area,
&srtr_record_table_params,
registry->record_table_handle,
CurrentSession->area);
typmod_table = dshash_attach(CurrentSession->area,
&srtr_typmod_table_params,
registry->typmod_table_handle,
NULL);
MemoryContextSwitchTo(old_context);
/*
* Set up detach hook to run at worker exit. Currently this is the same
* as the leader's detach hook, but in future they might need to be
* different.
*/
on_dsm_detach(CurrentSession->segment,
shared_record_typmod_registry_detach,
PointerGetDatum(registry));
/*
* Set up the session state that will tell assign_record_type_typmod and
* lookup_rowtype_tupdesc_internal about the shared registry.
*/
CurrentSession->shared_typmod_registry = registry;
CurrentSession->shared_record_table = record_table;
CurrentSession->shared_typmod_table = typmod_table;
}
/*
* TypeCacheRelCallback
* Relcache inval callback function
*
* Delete the cached tuple descriptor (if any) for the given rel's composite
* type, or for all composite types if relid == InvalidOid. Also reset
* whatever info we have cached about the composite type's comparability.
*
* This is called when a relcache invalidation event occurs for the given
* relid. We must scan the whole typcache hash since we don't know the
* type OID corresponding to the relid. We could do a direct search if this
* were a syscache-flush callback on pg_type, but then we would need all
* ALTER-TABLE-like commands that could modify a rowtype to issue syscache
* invals against the rel's pg_type OID. The extra SI signaling could very
* well cost more than we'd save, since in most usages there are not very
* many entries in a backend's typcache. The risk of bugs-of-omission seems
* high, too.
*
* Another possibility, with only localized impact, is to maintain a second
* hashtable that indexes composite-type typcache entries by their typrelid.
* But it's still not clear it's worth the trouble.
*/
static void
TypeCacheRelCallback(Datum arg, Oid relid)
{
HASH_SEQ_STATUS status;
TypeCacheEntry *typentry;
/* TypeCacheHash must exist, else this callback wouldn't be registered */
hash_seq_init(&status, TypeCacheHash);
while ((typentry = (TypeCacheEntry *) hash_seq_search(&status)) != NULL)
{
if (typentry->typtype == TYPTYPE_COMPOSITE)
{
/* Skip if no match, unless we're zapping all composite types */
if (relid != typentry->typrelid && relid != InvalidOid)
continue;
/* Delete tupdesc if we have it */
if (typentry->tupDesc != NULL)
{
/*
* Release our refcount, and free the tupdesc if none remain.
* (Can't use DecrTupleDescRefCount because this reference is
* not logged in current resource owner.)
*/
Assert(typentry->tupDesc->tdrefcount > 0);
if (--typentry->tupDesc->tdrefcount == 0)
FreeTupleDesc(typentry->tupDesc);
typentry->tupDesc = NULL;
/*
* Also clear tupDesc_identifier, so that anything watching
* that will realize that the tupdesc has possibly changed.
* (Alternatively, we could specify that to detect possible
* tupdesc change, one must check for tupDesc != NULL as well
* as tupDesc_identifier being the same as what was previously
* seen. That seems error-prone.)
*/
typentry->tupDesc_identifier = 0;
}
/* Reset equality/comparison/hashing validity information */
typentry->flags &= ~TCFLAGS_OPERATOR_FLAGS;
}
else if (typentry->typtype == TYPTYPE_DOMAIN)
{
/*
* If it's domain over composite, reset flags. (We don't bother
* trying to determine whether the specific base type needs a
* reset.) Note that if we haven't determined whether the base
* type is composite, we don't need to reset anything.
*/
if (typentry->flags & TCFLAGS_DOMAIN_BASE_IS_COMPOSITE)
typentry->flags &= ~TCFLAGS_OPERATOR_FLAGS;
}
}
}
/*
* TypeCacheTypCallback
* Syscache inval callback function
*
* This is called when a syscache invalidation event occurs for any
* pg_type row. If we have information cached about that type, mark
* it as needing to be reloaded.
*/
static void
TypeCacheTypCallback(Datum arg, int cacheid, uint32 hashvalue)
{
HASH_SEQ_STATUS status;
TypeCacheEntry *typentry;
/* TypeCacheHash must exist, else this callback wouldn't be registered */
hash_seq_init(&status, TypeCacheHash);
while ((typentry = (TypeCacheEntry *) hash_seq_search(&status)) != NULL)
{
/* Is this the targeted type row (or it's a total cache flush)? */
if (hashvalue == 0 || typentry->type_id_hash == hashvalue)
{
/*
* Mark the data obtained directly from pg_type as invalid. Also,
* if it's a domain, typnotnull might've changed, so we'll need to
* recalculate its constraints.
*/
typentry->flags &= ~(TCFLAGS_HAVE_PG_TYPE_DATA |
TCFLAGS_CHECKED_DOMAIN_CONSTRAINTS);
}
}
}
/*
* TypeCacheOpcCallback
* Syscache inval callback function
*
* This is called when a syscache invalidation event occurs for any pg_opclass
* row. In principle we could probably just invalidate data dependent on the
* particular opclass, but since updates on pg_opclass are rare in production
* it doesn't seem worth a lot of complication: we just mark all cached data
* invalid.
*
* Note that we don't bother watching for updates on pg_amop or pg_amproc.
* This should be safe because ALTER OPERATOR FAMILY ADD/DROP OPERATOR/FUNCTION
* is not allowed to be used to add/drop the primary operators and functions
* of an opclass, only cross-type members of a family; and the latter sorts
* of members are not going to get cached here.
*/
static void
TypeCacheOpcCallback(Datum arg, int cacheid, uint32 hashvalue)
{
HASH_SEQ_STATUS status;
TypeCacheEntry *typentry;
/* TypeCacheHash must exist, else this callback wouldn't be registered */
hash_seq_init(&status, TypeCacheHash);
while ((typentry = (TypeCacheEntry *) hash_seq_search(&status)) != NULL)
{
/* Reset equality/comparison/hashing validity information */
typentry->flags &= ~TCFLAGS_OPERATOR_FLAGS;
}
}
/*
* TypeCacheConstrCallback
* Syscache inval callback function
*
* This is called when a syscache invalidation event occurs for any
* pg_constraint row. We flush information about domain constraints
* when this happens.
*
* It's slightly annoying that we can't tell whether the inval event was for
* a domain constraint record or not; there's usually more update traffic
* for table constraints than domain constraints, so we'll do a lot of
* useless flushes. Still, this is better than the old no-caching-at-all
* approach to domain constraints.
*/
static void
TypeCacheConstrCallback(Datum arg, int cacheid, uint32 hashvalue)
{
TypeCacheEntry *typentry;
/*
* Because this is called very frequently, and typically very few of the
* typcache entries are for domains, we don't use hash_seq_search here.
* Instead we thread all the domain-type entries together so that we can
* visit them cheaply.
*/
for (typentry = firstDomainTypeEntry;
typentry != NULL;
typentry = typentry->nextDomain)
{
/* Reset domain constraint validity information */
typentry->flags &= ~TCFLAGS_CHECKED_DOMAIN_CONSTRAINTS;
}
}
/*
* build_tuple_node_list
*
* Wrap TupleDesc with TupleDescNode. Return all record type in record cache.
*/
List *
build_tuple_node_list(int start)
{
List *transientTypeList = NIL;
int i = start;
if (NextRecordTypmod == 0 && CurrentSession->shared_typmod_registry == NULL)
return transientTypeList;
for (; i < NextRecordTypmod; i++)
{
TupleDesc tmp = RecordCacheArray[i];
TupleDescNode *node = palloc0(sizeof(TupleDescNode));
node->type = T_TupleDescNode;
node->natts = tmp->natts;
node->tuple = CreateTupleDescCopy(tmp);
transientTypeList = lappend(transientTypeList, node);
}
if (CurrentSession->shared_typmod_registry != NULL)
{
for (; i < GetSharedNextRecordTypmod(CurrentSession->shared_typmod_registry); i++)
{
TupleDesc tmp = RecordCacheArray[i];
TupleDescNode *node = palloc0(sizeof(TupleDescNode));
node->type = T_TupleDescNode;
node->natts = tmp->natts;
node->tuple = CreateTupleDescCopy(tmp);
transientTypeList = lappend(transientTypeList, node);
}
}
return transientTypeList;
}
/*
* Check if given OID is part of the subset that's sortable by comparisons
*/
static inline bool
enum_known_sorted(TypeCacheEnumData *enumdata, Oid arg)
{
Oid offset;
if (arg < enumdata->bitmap_base)
return false;
offset = arg - enumdata->bitmap_base;
if (offset > (Oid) INT_MAX)
return false;
return bms_is_member((int) offset, enumdata->sorted_values);
}
/*
* compare_values_of_enum
* Compare two members of an enum type.
* Return <0, 0, or >0 according as arg1 <, =, or > arg2.
*
* Note: currently, the enumData cache is refreshed only if we are asked
* to compare an enum value that is not already in the cache. This is okay
* because there is no support for re-ordering existing values, so comparisons
* of previously cached values will return the right answer even if other
* values have been added since we last loaded the cache.
*
* Note: the enum logic has a special-case rule about even-numbered versus
* odd-numbered OIDs, but we take no account of that rule here; this
* routine shouldn't even get called when that rule applies.
*/
int
compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2)
{
TypeCacheEnumData *enumdata;
EnumItem *item1;
EnumItem *item2;
/*
* Equal OIDs are certainly equal --- this case was probably handled by
* our caller, but we may as well check.
*/
if (arg1 == arg2)
return 0;
/* Load up the cache if first time through */
if (tcache->enumData == NULL)
load_enum_cache_data(tcache);
enumdata = tcache->enumData;
/*
* If both OIDs are known-sorted, we can just compare them directly.
*/
if (enum_known_sorted(enumdata, arg1) &&
enum_known_sorted(enumdata, arg2))
{
if (arg1 < arg2)
return -1;
else
return 1;
}
/*
* Slow path: we have to identify their actual sort-order positions.
*/
item1 = find_enumitem(enumdata, arg1);
item2 = find_enumitem(enumdata, arg2);
if (item1 == NULL || item2 == NULL)
{
/*
* We couldn't find one or both values. That means the enum has
* changed under us, so re-initialize the cache and try again. We
* don't bother retrying the known-sorted case in this path.
*/
load_enum_cache_data(tcache);
enumdata = tcache->enumData;
item1 = find_enumitem(enumdata, arg1);
item2 = find_enumitem(enumdata, arg2);
/*
* If we still can't find the values, complain: we must have corrupt
* data.
*/
if (item1 == NULL)
elog(ERROR, "enum value %u not found in cache for enum %s",
arg1, format_type_be(tcache->type_id));
if (item2 == NULL)
elog(ERROR, "enum value %u not found in cache for enum %s",
arg2, format_type_be(tcache->type_id));
}
if (item1->sort_order < item2->sort_order)
return -1;
else if (item1->sort_order > item2->sort_order)
return 1;
else
return 0;
}
/*
* Load (or re-load) the enumData member of the typcache entry.
*/
static void
load_enum_cache_data(TypeCacheEntry *tcache)
{
TypeCacheEnumData *enumdata;
Relation enum_rel;
SysScanDesc enum_scan;
HeapTuple enum_tuple;
ScanKeyData skey;
EnumItem *items;
int numitems;
int maxitems;
Oid bitmap_base;
Bitmapset *bitmap;
MemoryContext oldcxt;
int bm_size,
start_pos;
/* Check that this is actually an enum */
if (tcache->typtype != TYPTYPE_ENUM)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("%s is not an enum",
format_type_be(tcache->type_id))));
/*
* Read all the information for members of the enum type. We collect the
* info in working memory in the caller's context, and then transfer it to
* permanent memory in CacheMemoryContext. This minimizes the risk of
* leaking memory from CacheMemoryContext in the event of an error partway
* through.
*/
maxitems = 64;
items = (EnumItem *) palloc(sizeof(EnumItem) * maxitems);
numitems = 0;
/* Scan pg_enum for the members of the target enum type. */
ScanKeyInit(&skey,
Anum_pg_enum_enumtypid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(tcache->type_id));
enum_rel = table_open(EnumRelationId, AccessShareLock);
enum_scan = systable_beginscan(enum_rel,
EnumTypIdLabelIndexId,
true, NULL,
1, &skey);
while (HeapTupleIsValid(enum_tuple = systable_getnext(enum_scan)))
{
Form_pg_enum en = (Form_pg_enum) GETSTRUCT(enum_tuple);
if (numitems >= maxitems)
{
maxitems *= 2;
items = (EnumItem *) repalloc(items, sizeof(EnumItem) * maxitems);
}
items[numitems].enum_oid = en->oid;
items[numitems].sort_order = en->enumsortorder;
numitems++;
}
systable_endscan(enum_scan);
table_close(enum_rel, AccessShareLock);
/* Sort the items into OID order */
qsort(items, numitems, sizeof(EnumItem), enum_oid_cmp);
/*
* Here, we create a bitmap listing a subset of the enum's OIDs that are
* known to be in order and can thus be compared with just OID comparison.
*
* The point of this is that the enum's initial OIDs were certainly in
* order, so there is some subset that can be compared via OID comparison;
* and we'd rather not do binary searches unnecessarily.
*
* This is somewhat heuristic, and might identify a subset of OIDs that
* isn't exactly what the type started with. That's okay as long as the
* subset is correctly sorted.
*/
bitmap_base = InvalidOid;
bitmap = NULL;
bm_size = 1; /* only save sets of at least 2 OIDs */
for (start_pos = 0; start_pos < numitems - 1; start_pos++)
{
/*
* Identify longest sorted subsequence starting at start_pos
*/
Bitmapset *this_bitmap = bms_make_singleton(0);
int this_bm_size = 1;
Oid start_oid = items[start_pos].enum_oid;
float4 prev_order = items[start_pos].sort_order;
int i;
for (i = start_pos + 1; i < numitems; i++)
{
Oid offset;
offset = items[i].enum_oid - start_oid;
/* quit if bitmap would be too large; cutoff is arbitrary */
if (offset >= 8192)
break;
/* include the item if it's in-order */
if (items[i].sort_order > prev_order)
{
prev_order = items[i].sort_order;
this_bitmap = bms_add_member(this_bitmap, (int) offset);
this_bm_size++;
}
}
/* Remember it if larger than previous best */
if (this_bm_size > bm_size)
{
bms_free(bitmap);
bitmap_base = start_oid;
bitmap = this_bitmap;
bm_size = this_bm_size;
}
else
bms_free(this_bitmap);
/*
* Done if it's not possible to find a longer sequence in the rest of
* the list. In typical cases this will happen on the first
* iteration, which is why we create the bitmaps on the fly instead of
* doing a second pass over the list.
*/
if (bm_size >= (numitems - start_pos - 1))
break;
}
/* OK, copy the data into CacheMemoryContext */
oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
enumdata = (TypeCacheEnumData *)
palloc(offsetof(TypeCacheEnumData, enum_values) +
numitems * sizeof(EnumItem));
enumdata->bitmap_base = bitmap_base;
enumdata->sorted_values = bms_copy(bitmap);
enumdata->num_values = numitems;
memcpy(enumdata->enum_values, items, numitems * sizeof(EnumItem));
MemoryContextSwitchTo(oldcxt);
pfree(items);
bms_free(bitmap);
/* And link the finished cache struct into the typcache */
if (tcache->enumData != NULL)
pfree(tcache->enumData);
tcache->enumData = enumdata;
}
/*
* Locate the EnumItem with the given OID, if present
*/
static EnumItem *
find_enumitem(TypeCacheEnumData *enumdata, Oid arg)
{
EnumItem srch;
/* On some versions of Solaris, bsearch of zero items dumps core */
if (enumdata->num_values <= 0)
return NULL;
srch.enum_oid = arg;
return bsearch(&srch, enumdata->enum_values, enumdata->num_values,
sizeof(EnumItem), enum_oid_cmp);
}
/*
* qsort comparison function for OID-ordered EnumItems
*/
static int
enum_oid_cmp(const void *left, const void *right)
{
const EnumItem *l = (const EnumItem *) left;
const EnumItem *r = (const EnumItem *) right;
if (l->enum_oid < r->enum_oid)
return -1;
else if (l->enum_oid > r->enum_oid)
return 1;
else
return 0;
}
/*
* Copy 'tupdesc' into newly allocated shared memory in 'area', set its typmod
* to the given value and return a dsa_pointer.
*/
static dsa_pointer
share_tupledesc(dsa_area *area, TupleDesc tupdesc, uint32 typmod)
{
dsa_pointer shared_dp;
TupleDesc shared;
shared_dp = dsa_allocate(area, TupleDescSize(tupdesc));
shared = (TupleDesc) dsa_get_address(area, shared_dp);
TupleDescCopy(shared, tupdesc);
shared->tdtypmod = typmod;
return shared_dp;
}
/*
* If we are attached to a SharedRecordTypmodRegistry, use it to find or
* create a shared TupleDesc that matches 'tupdesc'. Otherwise return NULL.
* Tuple descriptors returned by this function are not reference counted, and
* will exist at least as long as the current backend remained attached to the
* current session.
*/
static TupleDesc
find_or_make_matching_shared_tupledesc(TupleDesc tupdesc)
{
TupleDesc result;
SharedRecordTableKey key;
SharedRecordTableEntry *record_table_entry;
SharedTypmodTableEntry *typmod_table_entry;
dsa_pointer shared_dp;
bool found;
uint32 typmod;
/* If not even attached, nothing to do. */
if (CurrentSession->shared_typmod_registry == NULL)
return NULL;
/* Try to find a matching tuple descriptor in the record table. */
key.shared = false;
key.u.local_tupdesc = tupdesc;
record_table_entry = (SharedRecordTableEntry *)
dshash_find(CurrentSession->shared_record_table, &key, false);
if (record_table_entry)
{
Assert(record_table_entry->key.shared);
dshash_release_lock(CurrentSession->shared_record_table,
record_table_entry);
result = (TupleDesc)
dsa_get_address(CurrentSession->area,
record_table_entry->key.u.shared_tupdesc);
Assert(result->tdrefcount == -1);
return result;
}
/* Allocate a new typmod number. This will be wasted if we error out. */
typmod = (int)
pg_atomic_fetch_add_u32(&CurrentSession->shared_typmod_registry->next_typmod,
1);
/* Copy the TupleDesc into shared memory. */
shared_dp = share_tupledesc(CurrentSession->area, tupdesc, typmod);
/*
* Create an entry in the typmod table so that others will understand this
* typmod number.
*/
PG_TRY();
{
typmod_table_entry = (SharedTypmodTableEntry *)
dshash_find_or_insert(CurrentSession->shared_typmod_table,
&typmod, &found);
if (found)
elog(ERROR, "cannot create duplicate shared record typmod");
}
PG_CATCH();
{
dsa_free(CurrentSession->area, shared_dp);
PG_RE_THROW();
}
PG_END_TRY();
typmod_table_entry->typmod = typmod;
typmod_table_entry->shared_tupdesc = shared_dp;
dshash_release_lock(CurrentSession->shared_typmod_table,
typmod_table_entry);
/*
* Finally create an entry in the record table so others with matching
* tuple descriptors can reuse the typmod.
*/
record_table_entry = (SharedRecordTableEntry *)
dshash_find_or_insert(CurrentSession->shared_record_table, &key,
&found);
if (found)
{
/*
* Someone concurrently inserted a matching tuple descriptor since the
* first time we checked. Use that one instead.
*/
dshash_release_lock(CurrentSession->shared_record_table,
record_table_entry);
/* Might as well free up the space used by the one we created. */
found = dshash_delete_key(CurrentSession->shared_typmod_table,
&typmod);
Assert(found);
dsa_free(CurrentSession->area, shared_dp);
/* Return the one we found. */
Assert(record_table_entry->key.shared);
result = (TupleDesc)
dsa_get_address(CurrentSession->area,
record_table_entry->key.u.shared_tupdesc);
Assert(result->tdrefcount == -1);
return result;
}
/* Store it and return it. */
record_table_entry->key.shared = true;
record_table_entry->key.u.shared_tupdesc = shared_dp;
dshash_release_lock(CurrentSession->shared_record_table,
record_table_entry);
result = (TupleDesc)
dsa_get_address(CurrentSession->area, shared_dp);
Assert(result->tdrefcount == -1);
return result;
}
/*
* On-DSM-detach hook to forget about the current shared record typmod
* infrastructure. This is currently used by both leader and workers.
*/
static void
shared_record_typmod_registry_detach(dsm_segment *segment, Datum datum)
{
/* Be cautious here: maybe we didn't finish initializing. */
if (CurrentSession->shared_record_table != NULL)
{
dshash_detach(CurrentSession->shared_record_table);
CurrentSession->shared_record_table = NULL;
}
if (CurrentSession->shared_typmod_table != NULL)
{
dshash_detach(CurrentSession->shared_typmod_table);
CurrentSession->shared_typmod_table = NULL;
}
CurrentSession->shared_typmod_registry = NULL;
}