pg_type.c

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/*-------------------------------------------------------------------------
 *
 * pg_type.c
 *    routines to support manipulation of the pg_type relation
 *
 * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 *
 * IDENTIFICATION
 *    src/backend/catalog/pg_type.c
 *
 *-------------------------------------------------------------------------
 */
#include "postgres.h"
 
#include "access/htup_details.h"
#include "access/table.h"
#include "access/xact.h"
#include "catalog/binary_upgrade.h"
#include "catalog/catalog.h"
#include "catalog/dependency.h"
#include "catalog/indexing.h"
#include "catalog/objectaccess.h"
#include "catalog/pg_collation.h"
#include "catalog/pg_namespace.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_type.h"
#include "commands/defrem.h"
#include "commands/typecmds.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/lsyscache.h"
#include "utils/rel.h"
#include "utils/syscache.h"
 
/* Potentially set by pg_upgrade_support functions */
Oid         binary_upgrade_next_pg_type_oid = InvalidOid;
 
/* ----------------------------------------------------------------
 *      TypeShellMake
 *
 *      This procedure inserts a "shell" tuple into the pg_type relation.
 *      The type tuple inserted has valid but dummy values, and its
 *      "typisdefined" field is false indicating it's not really defined.
 *
 *      This is used so that a tuple exists in the catalogs.  The I/O
 *      functions for the type will link to this tuple.  When the full
 *      CREATE TYPE command is issued, the bogus values will be replaced
 *      with correct ones, and "typisdefined" will be set to true.
 * ----------------------------------------------------------------
 */
ObjectAddress
TypeShellMake(const char *typeName, Oid typeNamespace, Oid ownerId)
{
    Relation    pg_type_desc;
    TupleDesc   tupDesc;
    int         i;
    HeapTuple   tup;
    Datum       values[Natts_pg_type];
    bool        nulls[Natts_pg_type];
    Oid         typoid;
    NameData    name;
    ObjectAddress address;
 
    Assert(PointerIsValid(typeName));
 
    /*
     * open pg_type
     */
    pg_type_desc = table_open(TypeRelationId, RowExclusiveLock);
    tupDesc = pg_type_desc->rd_att;
 
    /*
     * initialize our *nulls and *values arrays
     */
    for (i = 0; i < Natts_pg_type; ++i)
    {
        nulls[i] = false;
        values[i] = (Datum) NULL;   /* redundant, but safe */
    }
 
    /*
     * initialize *values with the type name and dummy values
     *
     * The representational details are the same as int4 ... it doesn't really
     * matter what they are so long as they are consistent.  Also note that we
     * give it typtype = TYPTYPE_PSEUDO as extra insurance that it won't be
     * mistaken for a usable type.
     */
    namestrcpy(&name, typeName);
    values[Anum_pg_type_typname - 1] = NameGetDatum(&name);
    values[Anum_pg_type_typnamespace - 1] = ObjectIdGetDatum(typeNamespace);
    values[Anum_pg_type_typowner - 1] = ObjectIdGetDatum(ownerId);
    values[Anum_pg_type_typlen - 1] = Int16GetDatum(sizeof(int32));
    values[Anum_pg_type_typbyval - 1] = BoolGetDatum(true);
    values[Anum_pg_type_typtype - 1] = CharGetDatum(TYPTYPE_PSEUDO);
    values[Anum_pg_type_typcategory - 1] = CharGetDatum(TYPCATEGORY_PSEUDOTYPE);
    values[Anum_pg_type_typispreferred - 1] = BoolGetDatum(false);
    values[Anum_pg_type_typisdefined - 1] = BoolGetDatum(false);
    values[Anum_pg_type_typdelim - 1] = CharGetDatum(DEFAULT_TYPDELIM);
    values[Anum_pg_type_typrelid - 1] = ObjectIdGetDatum(InvalidOid);
    values[Anum_pg_type_typsubscript - 1] = ObjectIdGetDatum(InvalidOid);
    values[Anum_pg_type_typelem - 1] = ObjectIdGetDatum(InvalidOid);
    values[Anum_pg_type_typarray - 1] = ObjectIdGetDatum(InvalidOid);
    values[Anum_pg_type_typinput - 1] = ObjectIdGetDatum(F_SHELL_IN);
    values[Anum_pg_type_typoutput - 1] = ObjectIdGetDatum(F_SHELL_OUT);
    values[Anum_pg_type_typreceive - 1] = ObjectIdGetDatum(InvalidOid);
    values[Anum_pg_type_typsend - 1] = ObjectIdGetDatum(InvalidOid);
    values[Anum_pg_type_typmodin - 1] = ObjectIdGetDatum(InvalidOid);
    values[Anum_pg_type_typmodout - 1] = ObjectIdGetDatum(InvalidOid);
    values[Anum_pg_type_typanalyze - 1] = ObjectIdGetDatum(InvalidOid);
    values[Anum_pg_type_typalign - 1] = CharGetDatum(TYPALIGN_INT);
    values[Anum_pg_type_typstorage - 1] = CharGetDatum(TYPSTORAGE_PLAIN);
    values[Anum_pg_type_typnotnull - 1] = BoolGetDatum(false);
    values[Anum_pg_type_typbasetype - 1] = ObjectIdGetDatum(InvalidOid);
    values[Anum_pg_type_typtypmod - 1] = Int32GetDatum(-1);
    values[Anum_pg_type_typndims - 1] = Int32GetDatum(0);
    values[Anum_pg_type_typcollation - 1] = ObjectIdGetDatum(InvalidOid);
    nulls[Anum_pg_type_typdefaultbin - 1] = true;
    nulls[Anum_pg_type_typdefault - 1] = true;
    nulls[Anum_pg_type_typacl - 1] = true;
 
    /* Use binary-upgrade override for pg_type.oid? */
    if (IsBinaryUpgrade)
    {
        if (!OidIsValid(binary_upgrade_next_pg_type_oid))
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("pg_type OID value not set when in binary upgrade mode")));
 
        typoid = binary_upgrade_next_pg_type_oid;
        binary_upgrade_next_pg_type_oid = InvalidOid;
    }
    else
    {
        typoid = GetNewOidWithIndex(pg_type_desc, TypeOidIndexId,
                                    Anum_pg_type_oid);
    }
 
    values[Anum_pg_type_oid - 1] = ObjectIdGetDatum(typoid);
 
    /*
     * create a new type tuple
     */
    tup = heap_form_tuple(tupDesc, values, nulls);
 
    /*
     * insert the tuple in the relation and get the tuple's oid.
     */
    CatalogTupleInsert(pg_type_desc, tup);
 
    /*
     * Create dependencies.  We can/must skip this in bootstrap mode.
     */
    if (!IsBootstrapProcessingMode())
        GenerateTypeDependencies(tup,
                                 pg_type_desc,
                                 NULL,
                                 NULL,
                                 0,
                                 false,
                                 false,
                                 true,  /* make extension dependency */
                                 false);
 
    /* Post creation hook for new shell type */
    InvokeObjectPostCreateHook(TypeRelationId, typoid, 0);
 
    ObjectAddressSet(address, TypeRelationId, typoid);
 
    /*
     * clean up and return the type-oid
     */
    heap_freetuple(tup);
    table_close(pg_type_desc, RowExclusiveLock);
 
    return address;
}
 
/* ----------------------------------------------------------------
 *      TypeCreate
 *
 *      This does all the necessary work needed to define a new type.
 *
 *      Returns the ObjectAddress assigned to the new type.
 *      If newTypeOid is zero (the normal case), a new OID is created;
 *      otherwise we use exactly that OID.
 * ----------------------------------------------------------------
 */
ObjectAddress
TypeCreate(Oid newTypeOid,
           const char *typeName,
           Oid typeNamespace,
           Oid relationOid,     /* only for relation rowtypes */
           char relationKind,   /* ditto */
           Oid ownerId,
           int16 internalSize,
           char typeType,
           char typeCategory,
           bool typePreferred,
           char typDelim,
           Oid inputProcedure,
           Oid outputProcedure,
           Oid receiveProcedure,
           Oid sendProcedure,
           Oid typmodinProcedure,
           Oid typmodoutProcedure,
           Oid analyzeProcedure,
           Oid subscriptProcedure,
           Oid elementType,
           bool isImplicitArray,
           Oid arrayType,
           Oid baseType,
           const char *defaultTypeValue,    /* human-readable rep */
           char *defaultTypeBin,    /* cooked rep */
           bool passedByValue,
           char alignment,
           char storage,
           int32 typeMod,
           int32 typNDims,      /* Array dimensions for baseType */
           bool typeNotNull,
           Oid typeCollation)
{
    Relation    pg_type_desc;
    Oid         typeObjectId;
    bool        isDependentType;
    bool        rebuildDeps = false;
    Acl        *typacl;
    HeapTuple   tup;
    bool        nulls[Natts_pg_type];
    bool        replaces[Natts_pg_type];
    Datum       values[Natts_pg_type];
    NameData    name;
    int         i;
    ObjectAddress address;
 
    /*
     * We assume that the caller validated the arguments individually, but did
     * not check for bad combinations.
     *
     * Validate size specifications: either positive (fixed-length) or -1
     * (varlena) or -2 (cstring).
     */
    if (!(internalSize > 0 ||
          internalSize == -1 ||
          internalSize == -2))
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
                 errmsg("invalid type internal size %d",
                        internalSize)));
 
    if (passedByValue)
    {
        /*
         * Pass-by-value types must have a fixed length that is one of the
         * values supported by fetch_att() and store_att_byval(); and the
         * alignment had better agree, too.  All this code must match
         * access/tupmacs.h!
         */
        if (internalSize == (int16) sizeof(char))
        {
            if (alignment != TYPALIGN_CHAR)
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
                         errmsg("alignment \"%c\" is invalid for passed-by-value type of size %d",
                                alignment, internalSize)));
        }
        else if (internalSize == (int16) sizeof(int16))
        {
            if (alignment != TYPALIGN_SHORT)
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
                         errmsg("alignment \"%c\" is invalid for passed-by-value type of size %d",
                                alignment, internalSize)));
        }
        else if (internalSize == (int16) sizeof(int32))
        {
            if (alignment != TYPALIGN_INT)
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
                         errmsg("alignment \"%c\" is invalid for passed-by-value type of size %d",
                                alignment, internalSize)));
        }
#if SIZEOF_DATUM == 8
        else if (internalSize == (int16) sizeof(Datum))
        {
            if (alignment != TYPALIGN_DOUBLE)
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
                         errmsg("alignment \"%c\" is invalid for passed-by-value type of size %d",
                                alignment, internalSize)));
        }
#endif
        else
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
                     errmsg("internal size %d is invalid for passed-by-value type",
                            internalSize)));
    }
    else
    {
        /* varlena types must have int align or better */
        if (internalSize == -1 &&
            !(alignment == TYPALIGN_INT || alignment == TYPALIGN_DOUBLE))
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
                     errmsg("alignment \"%c\" is invalid for variable-length type",
                            alignment)));
        /* cstring must have char alignment */
        if (internalSize == -2 && !(alignment == TYPALIGN_CHAR))
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
                     errmsg("alignment \"%c\" is invalid for variable-length type",
                            alignment)));
    }
 
    /* Only varlena types can be toasted */
    if (storage != TYPSTORAGE_PLAIN && internalSize != -1)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
                 errmsg("fixed-size types must have storage PLAIN")));
 
    /*
     * This is a dependent type if it's an implicitly-created array type or
     * multirange type, or if it's a relation rowtype that's not a composite
     * type.  For such types we'll leave the ACL empty, and we'll skip
     * creating some dependency records because there will be a dependency
     * already through the depended-on type or relation.  (Caution: this is
     * closely intertwined with some behavior in GenerateTypeDependencies.)
     */
    isDependentType = isImplicitArray ||
        typeType == TYPTYPE_MULTIRANGE ||
        (OidIsValid(relationOid) && relationKind != RELKIND_COMPOSITE_TYPE);
 
    /*
     * initialize arrays needed for heap_form_tuple or heap_modify_tuple
     */
    for (i = 0; i < Natts_pg_type; ++i)
    {
        nulls[i] = false;
        replaces[i] = true;
        values[i] = (Datum) 0;
    }
 
    /*
     * insert data values
     */
    namestrcpy(&name, typeName);
    values[Anum_pg_type_typname - 1] = NameGetDatum(&name);
    values[Anum_pg_type_typnamespace - 1] = ObjectIdGetDatum(typeNamespace);
    values[Anum_pg_type_typowner - 1] = ObjectIdGetDatum(ownerId);
    values[Anum_pg_type_typlen - 1] = Int16GetDatum(internalSize);
    values[Anum_pg_type_typbyval - 1] = BoolGetDatum(passedByValue);
    values[Anum_pg_type_typtype - 1] = CharGetDatum(typeType);
    values[Anum_pg_type_typcategory - 1] = CharGetDatum(typeCategory);
    values[Anum_pg_type_typispreferred - 1] = BoolGetDatum(typePreferred);
    values[Anum_pg_type_typisdefined - 1] = BoolGetDatum(true);
    values[Anum_pg_type_typdelim - 1] = CharGetDatum(typDelim);
    values[Anum_pg_type_typrelid - 1] = ObjectIdGetDatum(relationOid);
    values[Anum_pg_type_typsubscript - 1] = ObjectIdGetDatum(subscriptProcedure);
    values[Anum_pg_type_typelem - 1] = ObjectIdGetDatum(elementType);
    values[Anum_pg_type_typarray - 1] = ObjectIdGetDatum(arrayType);
    values[Anum_pg_type_typinput - 1] = ObjectIdGetDatum(inputProcedure);
    values[Anum_pg_type_typoutput - 1] = ObjectIdGetDatum(outputProcedure);
    values[Anum_pg_type_typreceive - 1] = ObjectIdGetDatum(receiveProcedure);
    values[Anum_pg_type_typsend - 1] = ObjectIdGetDatum(sendProcedure);
    values[Anum_pg_type_typmodin - 1] = ObjectIdGetDatum(typmodinProcedure);
    values[Anum_pg_type_typmodout - 1] = ObjectIdGetDatum(typmodoutProcedure);
    values[Anum_pg_type_typanalyze - 1] = ObjectIdGetDatum(analyzeProcedure);
    values[Anum_pg_type_typalign - 1] = CharGetDatum(alignment);
    values[Anum_pg_type_typstorage - 1] = CharGetDatum(storage);
    values[Anum_pg_type_typnotnull - 1] = BoolGetDatum(typeNotNull);
    values[Anum_pg_type_typbasetype - 1] = ObjectIdGetDatum(baseType);
    values[Anum_pg_type_typtypmod - 1] = Int32GetDatum(typeMod);
    values[Anum_pg_type_typndims - 1] = Int32GetDatum(typNDims);
    values[Anum_pg_type_typcollation - 1] = ObjectIdGetDatum(typeCollation);
 
    /*
     * initialize the default binary value for this type.  Check for nulls of
     * course.
     */
    if (defaultTypeBin)
        values[Anum_pg_type_typdefaultbin - 1] = CStringGetTextDatum(defaultTypeBin);
    else
        nulls[Anum_pg_type_typdefaultbin - 1] = true;
 
    /*
     * initialize the default value for this type.
     */
    if (defaultTypeValue)
        values[Anum_pg_type_typdefault - 1] = CStringGetTextDatum(defaultTypeValue);
    else
        nulls[Anum_pg_type_typdefault - 1] = true;
 
    /*
     * Initialize the type's ACL, too.  But dependent types don't get one.
     */
    if (isDependentType)
        typacl = NULL;
    else
        typacl = get_user_default_acl(OBJECT_TYPE, ownerId,
                                      typeNamespace);
    if (typacl != NULL)
        values[Anum_pg_type_typacl - 1] = PointerGetDatum(typacl);
    else
        nulls[Anum_pg_type_typacl - 1] = true;
 
    /*
     * open pg_type and prepare to insert or update a row.
     *
     * NOTE: updating will not work correctly in bootstrap mode; but we don't
     * expect to be overwriting any shell types in bootstrap mode.
     */
    pg_type_desc = table_open(TypeRelationId, RowExclusiveLock);
 
    tup = SearchSysCacheCopy2(TYPENAMENSP,
                              CStringGetDatum(typeName),
                              ObjectIdGetDatum(typeNamespace));
    if (HeapTupleIsValid(tup))
    {
        Form_pg_type typform = (Form_pg_type) GETSTRUCT(tup);
 
        /*
         * check that the type is not already defined.  It may exist as a
         * shell type, however.
         */
        if (typform->typisdefined)
            ereport(ERROR,
                    (errcode(ERRCODE_DUPLICATE_OBJECT),
                     errmsg("type \"%s\" already exists", typeName)));
 
        /*
         * shell type must have been created by same owner
         */
        if (typform->typowner != ownerId)
            aclcheck_error(ACLCHECK_NOT_OWNER, OBJECT_TYPE, typeName);
 
        /* trouble if caller wanted to force the OID */
        if (OidIsValid(newTypeOid))
            elog(ERROR, "cannot assign new OID to existing shell type");
 
        replaces[Anum_pg_type_oid - 1] = false;
 
        /*
         * Okay to update existing shell type tuple
         */
        tup = heap_modify_tuple(tup,
                                RelationGetDescr(pg_type_desc),
                                values,
                                nulls,
                                replaces);
 
        CatalogTupleUpdate(pg_type_desc, &tup->t_self, tup);
 
        typeObjectId = typform->oid;
 
        rebuildDeps = true;     /* get rid of shell type's dependencies */
    }
    else
    {
        /* Force the OID if requested by caller */
        if (OidIsValid(newTypeOid))
            typeObjectId = newTypeOid;
        /* Use binary-upgrade override for pg_type.oid, if supplied. */
        else if (IsBinaryUpgrade)
        {
            if (!OidIsValid(binary_upgrade_next_pg_type_oid))
                ereport(ERROR,
                        (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("pg_type OID value not set when in binary upgrade mode")));
 
            typeObjectId = binary_upgrade_next_pg_type_oid;
            binary_upgrade_next_pg_type_oid = InvalidOid;
        }
        else
        {
            typeObjectId = GetNewOidWithIndex(pg_type_desc, TypeOidIndexId,
                                              Anum_pg_type_oid);
        }
 
        values[Anum_pg_type_oid - 1] = ObjectIdGetDatum(typeObjectId);
 
        tup = heap_form_tuple(RelationGetDescr(pg_type_desc),
                              values, nulls);
 
        CatalogTupleInsert(pg_type_desc, tup);
    }
 
    /*
     * Create dependencies.  We can/must skip this in bootstrap mode.
     */
    if (!IsBootstrapProcessingMode())
        GenerateTypeDependencies(tup,
                                 pg_type_desc,
                                 (defaultTypeBin ?
                                  stringToNode(defaultTypeBin) :
                                  NULL),
                                 typacl,
                                 relationKind,
                                 isImplicitArray,
                                 isDependentType,
                                 true,  /* make extension dependency */
                                 rebuildDeps);
 
    /* Post creation hook for new type */
    InvokeObjectPostCreateHook(TypeRelationId, typeObjectId, 0);
 
    ObjectAddressSet(address, TypeRelationId, typeObjectId);
 
    /*
     * finish up
     */
    table_close(pg_type_desc, RowExclusiveLock);
 
    return address;
}
 
/*
 * GenerateTypeDependencies: build the dependencies needed for a type
 *
 * Most of what this function needs to know about the type is passed as the
 * new pg_type row, typeTuple.  We make callers pass the pg_type Relation
 * as well, so that we have easy access to a tuple descriptor for the row.
 *
 * While this is able to extract the defaultExpr and typacl from the tuple,
 * doing so is relatively expensive, and callers may have those values at
 * hand already.  Pass those if handy, otherwise pass NULL.  (typacl is really
 * "Acl *", but we declare it "void *" to avoid including acl.h in pg_type.h.)
 *
 * relationKind and isImplicitArray are likewise somewhat expensive to deduce
 * from the tuple, so we make callers pass those (they're not optional).
 *
 * isDependentType is true if this is an implicit array, multirange, or
 * relation rowtype; that means it doesn't need its own dependencies on owner
 * etc.
 *
 * We make an extension-membership dependency if we're in an extension
 * script and makeExtensionDep is true.
 * makeExtensionDep should be true when creating a new type or replacing a
 * shell type, but not for ALTER TYPE on an existing type.  Passing false
 * causes the type's extension membership to be left alone.
 *
 * rebuild should be true if this is a pre-existing type.  We will remove
 * existing dependencies and rebuild them from scratch.  This is needed for
 * ALTER TYPE, and also when replacing a shell type.  We don't remove any
 * existing extension dependency, though; hence, if makeExtensionDep is also
 * true and we're in an extension script, an error will occur unless the
 * type already belongs to the current extension.  That's the behavior we
 * want when replacing a shell type, which is the only case where both flags
 * are true.
 */
void
GenerateTypeDependencies(HeapTuple typeTuple,
                         Relation typeCatalog,
                         Node *defaultExpr,
                         void *typacl,
                         char relationKind, /* only for relation rowtypes */
                         bool isImplicitArray,
                         bool isDependentType,
                         bool makeExtensionDep,
                         bool rebuild)
{
    Form_pg_type typeForm = (Form_pg_type) GETSTRUCT(typeTuple);
    Oid         typeObjectId = typeForm->oid;
    Datum       datum;
    bool        isNull;
    ObjectAddress myself,
                referenced;
    ObjectAddresses *addrs_normal;
 
    /* Extract defaultExpr if caller didn't pass it */
    if (defaultExpr == NULL)
    {
        datum = heap_getattr(typeTuple, Anum_pg_type_typdefaultbin,
                             RelationGetDescr(typeCatalog), &isNull);
        if (!isNull)
            defaultExpr = stringToNode(TextDatumGetCString(datum));
    }
    /* Extract typacl if caller didn't pass it */
    if (typacl == NULL)
    {
        datum = heap_getattr(typeTuple, Anum_pg_type_typacl,
                             RelationGetDescr(typeCatalog), &isNull);
        if (!isNull)
            typacl = DatumGetAclPCopy(datum);
    }
 
    /* If rebuild, first flush old dependencies, except extension deps */
    if (rebuild)
    {
        deleteDependencyRecordsFor(TypeRelationId, typeObjectId, true);
        deleteSharedDependencyRecordsFor(TypeRelationId, typeObjectId, 0);
    }
 
    ObjectAddressSet(myself, TypeRelationId, typeObjectId);
 
    /*
     * Make dependencies on namespace, owner, ACL.
     *
     * Skip these for a dependent type, since it will have such dependencies
     * indirectly through its depended-on type or relation.  An exception is
     * that multiranges need their own namespace dependency, since we don't
     * force them to be in the same schema as their range type.
     */
 
    /* collects normal dependencies for bulk recording */
    addrs_normal = new_object_addresses();
 
    if (!isDependentType || typeForm->typtype == TYPTYPE_MULTIRANGE)
    {
        ObjectAddressSet(referenced, NamespaceRelationId,
                         typeForm->typnamespace);
        add_exact_object_address(&referenced, addrs_normal);
    }
 
    if (!isDependentType)
    {
        recordDependencyOnOwner(TypeRelationId, typeObjectId,
                                typeForm->typowner);
 
        recordDependencyOnNewAcl(TypeRelationId, typeObjectId, 0,
                                 typeForm->typowner, typacl);
    }
 
    /*
     * Make extension dependency if requested.
     *
     * We used to skip this for dependent types, but it seems better to record
     * their extension membership explicitly; otherwise code such as
     * postgres_fdw's shippability test will be fooled.
     */
    if (makeExtensionDep)
        recordDependencyOnCurrentExtension(&myself, rebuild);
 
    /* Normal dependencies on the I/O and support functions */
    if (OidIsValid(typeForm->typinput))
    {
        ObjectAddressSet(referenced, ProcedureRelationId, typeForm->typinput);
        add_exact_object_address(&referenced, addrs_normal);
    }
 
    if (OidIsValid(typeForm->typoutput))
    {
        ObjectAddressSet(referenced, ProcedureRelationId, typeForm->typoutput);
        add_exact_object_address(&referenced, addrs_normal);
    }
 
    if (OidIsValid(typeForm->typreceive))
    {
        ObjectAddressSet(referenced, ProcedureRelationId, typeForm->typreceive);
        add_exact_object_address(&referenced, addrs_normal);
    }
 
    if (OidIsValid(typeForm->typsend))
    {
        ObjectAddressSet(referenced, ProcedureRelationId, typeForm->typsend);
        add_exact_object_address(&referenced, addrs_normal);
    }
 
    if (OidIsValid(typeForm->typmodin))
    {
        ObjectAddressSet(referenced, ProcedureRelationId, typeForm->typmodin);
        add_exact_object_address(&referenced, addrs_normal);
    }
 
    if (OidIsValid(typeForm->typmodout))
    {
        ObjectAddressSet(referenced, ProcedureRelationId, typeForm->typmodout);
        add_exact_object_address(&referenced, addrs_normal);
    }
 
    if (OidIsValid(typeForm->typanalyze))
    {
        ObjectAddressSet(referenced, ProcedureRelationId, typeForm->typanalyze);
        add_exact_object_address(&referenced, addrs_normal);
    }
 
    if (OidIsValid(typeForm->typsubscript))
    {
        ObjectAddressSet(referenced, ProcedureRelationId, typeForm->typsubscript);
        add_exact_object_address(&referenced, addrs_normal);
    }
 
    /* Normal dependency from a domain to its base type. */
    if (OidIsValid(typeForm->typbasetype))
    {
        ObjectAddressSet(referenced, TypeRelationId, typeForm->typbasetype);
        add_exact_object_address(&referenced, addrs_normal);
    }
 
    /*
     * Normal dependency from a domain to its collation.  We know the default
     * collation is pinned, so don't bother recording it.
     */
    if (OidIsValid(typeForm->typcollation) &&
        typeForm->typcollation != DEFAULT_COLLATION_OID)
    {
        ObjectAddressSet(referenced, CollationRelationId, typeForm->typcollation);
        add_exact_object_address(&referenced, addrs_normal);
    }
 
    record_object_address_dependencies(&myself, addrs_normal, DEPENDENCY_NORMAL);
    free_object_addresses(addrs_normal);
 
    /* Normal dependency on the default expression. */
    if (defaultExpr)
        recordDependencyOnExpr(&myself, defaultExpr, NIL, DEPENDENCY_NORMAL);
 
    /*
     * If the type is a rowtype for a relation, mark it as internally
     * dependent on the relation, *unless* it is a stand-alone composite type
     * relation. For the latter case, we have to reverse the dependency.
     *
     * In the former case, this allows the type to be auto-dropped when the
     * relation is, and not otherwise. And in the latter, of course we get the
     * opposite effect.
     */
    if (OidIsValid(typeForm->typrelid))
    {
        ObjectAddressSet(referenced, RelationRelationId, typeForm->typrelid);
 
        if (relationKind != RELKIND_COMPOSITE_TYPE)
            recordDependencyOn(&myself, &referenced, DEPENDENCY_INTERNAL);
        else
            recordDependencyOn(&referenced, &myself, DEPENDENCY_INTERNAL);
    }
 
    /*
     * If the type is an implicitly-created array type, mark it as internally
     * dependent on the element type.  Otherwise, if it has an element type,
     * the dependency is a normal one.
     */
    if (OidIsValid(typeForm->typelem))
    {
        ObjectAddressSet(referenced, TypeRelationId, typeForm->typelem);
        recordDependencyOn(&myself, &referenced,
                           isImplicitArray ? DEPENDENCY_INTERNAL : DEPENDENCY_NORMAL);
    }
 
    /*
     * Note: you might expect that we should record an internal dependency of
     * a multirange on its range type here, by analogy with the cases above.
     * But instead, that is done by RangeCreate(), which also handles
     * recording of other range-type-specific dependencies.  That's pretty
     * bogus.  It's okay for now, because there are no cases where we need to
     * regenerate the dependencies of a range or multirange type.  But someday
     * we might need to move that logic here to allow such regeneration.
     */
}
 
/*
 * RenameTypeInternal
 *      This renames a type, as well as any associated array type.
 *
 * Caller must have already checked privileges.
 *
 * Currently this is used for renaming table rowtypes and for
 * ALTER TYPE RENAME TO command.
 */
void
RenameTypeInternal(Oid typeOid, const char *newTypeName, Oid typeNamespace)
{
    Relation    pg_type_desc;
    HeapTuple   tuple;
    Form_pg_type typ;
    Oid         arrayOid;
    Oid         oldTypeOid;
 
    pg_type_desc = table_open(TypeRelationId, RowExclusiveLock);
 
    tuple = SearchSysCacheCopy1(TYPEOID, ObjectIdGetDatum(typeOid));
    if (!HeapTupleIsValid(tuple))
        elog(ERROR, "cache lookup failed for type %u", typeOid);
    typ = (Form_pg_type) GETSTRUCT(tuple);
 
    /* We are not supposed to be changing schemas here */
    Assert(typeNamespace == typ->typnamespace);
 
    arrayOid = typ->typarray;
 
    /* Check for a conflicting type name. */
    oldTypeOid = GetSysCacheOid2(TYPENAMENSP, Anum_pg_type_oid,
                                 CStringGetDatum(newTypeName),
                                 ObjectIdGetDatum(typeNamespace));
 
    /*
     * If there is one, see if it's an autogenerated array type, and if so
     * rename it out of the way.  (But we must skip that for a shell type
     * because moveArrayTypeName will do the wrong thing in that case.)
     * Otherwise, we can at least give a more friendly error than unique-index
     * violation.
     */
    if (OidIsValid(oldTypeOid))
    {
        if (get_typisdefined(oldTypeOid) &&
            moveArrayTypeName(oldTypeOid, newTypeName, typeNamespace))
             /* successfully dodged the problem */ ;
        else
            ereport(ERROR,
                    (errcode(ERRCODE_DUPLICATE_OBJECT),
                     errmsg("type \"%s\" already exists", newTypeName)));
    }
 
    /* OK, do the rename --- tuple is a copy, so OK to scribble on it */
    namestrcpy(&(typ->typname), newTypeName);
 
    CatalogTupleUpdate(pg_type_desc, &tuple->t_self, tuple);
 
    InvokeObjectPostAlterHook(TypeRelationId, typeOid, 0);
 
    heap_freetuple(tuple);
    table_close(pg_type_desc, RowExclusiveLock);
 
    /*
     * If the type has an array type, recurse to handle that.  But we don't
     * need to do anything more if we already renamed that array type above
     * (which would happen when, eg, renaming "foo" to "_foo").
     */
    if (OidIsValid(arrayOid) && arrayOid != oldTypeOid)
    {
        char       *arrname = makeArrayTypeName(newTypeName, typeNamespace);
 
        RenameTypeInternal(arrayOid, arrname, typeNamespace);
        pfree(arrname);
    }
}
 
 
/*
 * makeArrayTypeName
 *    - given a base type name, make an array type name for it
 *
 * the caller is responsible for pfreeing the result
 */
char *
makeArrayTypeName(const char *typeName, Oid typeNamespace)
{
    char       *arr_name;
    int         pass = 0;
    char        suffix[NAMEDATALEN];
 
    /*
     * Per ancient Postgres tradition, array type names are made by prepending
     * an underscore to the base type name.  Much client code knows that
     * convention, so don't muck with it.  However, the tradition is less
     * clear about what to do in the corner cases where the resulting name is
     * too long or conflicts with an existing name.  Our current rules are (1)
     * truncate the base name on the right as needed, and (2) if there is a
     * conflict, append another underscore and some digits chosen to make it
     * unique.  This is similar to what ChooseRelationName() does.
     *
     * The actual name generation can be farmed out to makeObjectName() by
     * giving it an empty first name component.
     */
 
    /* First, try with no numeric suffix */
    arr_name = makeObjectName("", typeName, NULL);
 
    for (;;)
    {
        if (!SearchSysCacheExists2(TYPENAMENSP,
                                   CStringGetDatum(arr_name),
                                   ObjectIdGetDatum(typeNamespace)))
            break;
 
        /* That attempt conflicted.  Prepare a new name with some digits. */
        pfree(arr_name);
        snprintf(suffix, sizeof(suffix), "%d", ++pass);
        arr_name = makeObjectName("", typeName, suffix);
    }
 
    return arr_name;
}
 
 
/*
 * moveArrayTypeName
 *    - try to reassign an array type name that the user wants to use.
 *
 * The given type name has been discovered to already exist (with the given
 * OID).  If it is an autogenerated array type, change the array type's name
 * to not conflict.  This allows the user to create type "foo" followed by
 * type "_foo" without problems.  (Of course, there are race conditions if
 * two backends try to create similarly-named types concurrently, but the
 * worst that can happen is an unnecessary failure --- anything we do here
 * will be rolled back if the type creation fails due to conflicting names.)
 *
 * Note that this must be called *before* calling makeArrayTypeName to
 * determine the new type's own array type name; else the latter will
 * certainly pick the same name.
 *
 * Returns true if successfully moved the type, false if not.
 *
 * We also return true if the given type is a shell type.  In this case
 * the type has not been renamed out of the way, but nonetheless it can
 * be expected that TypeCreate will succeed.  This behavior is convenient
 * for most callers --- those that need to distinguish the shell-type case
 * must do their own typisdefined test.
 */
bool
moveArrayTypeName(Oid typeOid, const char *typeName, Oid typeNamespace)
{
    Oid         elemOid;
    char       *newname;
 
    /* We need do nothing if it's a shell type. */
    if (!get_typisdefined(typeOid))
        return true;
 
    /* Can't change it if it's not an autogenerated array type. */
    elemOid = get_element_type(typeOid);
    if (!OidIsValid(elemOid) ||
        get_array_type(elemOid) != typeOid)
        return false;
 
    /*
     * OK, use makeArrayTypeName to pick an unused modification of the name.
     * Note that since makeArrayTypeName is an iterative process, this will
     * produce a name that it might have produced the first time, had the
     * conflicting type we are about to create already existed.
     */
    newname = makeArrayTypeName(typeName, typeNamespace);
 
    /* Apply the rename */
    RenameTypeInternal(typeOid, newname, typeNamespace);
 
    /*
     * We must bump the command counter so that any subsequent use of
     * makeArrayTypeName sees what we just did and doesn't pick the same name.
     */
    CommandCounterIncrement();
 
    pfree(newname);
 
    return true;
}
 
 
/*
 * makeMultirangeTypeName
 *    - given a range type name, make a multirange type name for it
 *
 * caller is responsible for pfreeing the result
 */
char *
makeMultirangeTypeName(const char *rangeTypeName, Oid typeNamespace)
{
    char       *buf;
    char       *rangestr;
 
    /*
     * If the range type name contains "range" then change that to
     * "multirange". Otherwise add "_multirange" to the end.
     */
    rangestr = strstr(rangeTypeName, "range");
    if (rangestr)
    {
        char       *prefix = pnstrdup(rangeTypeName, rangestr - rangeTypeName);
 
        buf = psprintf("%s%s%s", prefix, "multi", rangestr);
    }
    else
        buf = psprintf("%s_multirange", pnstrdup(rangeTypeName, NAMEDATALEN - 12));
 
    /* clip it at NAMEDATALEN-1 bytes */
    buf[pg_mbcliplen(buf, strlen(buf), NAMEDATALEN - 1)] = '\0';
 
    if (SearchSysCacheExists2(TYPENAMENSP,
                              CStringGetDatum(buf),
                              ObjectIdGetDatum(typeNamespace)))
        ereport(ERROR,
                (errcode(ERRCODE_DUPLICATE_OBJECT),
                 errmsg("type \"%s\" already exists", buf),
                 errdetail("Failed while creating a multirange type for type \"%s\".", rangeTypeName),
                 errhint("You can manually specify a multirange type name using the \"multirange_type_name\" attribute.")));
 
    return pstrdup(buf);
}