sepgsql: update TAP test to use fat comma style

[pgsql.git] / src / backend / utils / adt / acl.c

/*-------------------------------------------------------------------------
 *
 * acl.c
 *        Basic access control list data structures manipulation routines.
 *
 * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 *
 * IDENTIFICATION
 *        src/backend/utils/adt/acl.c
 *
 *-------------------------------------------------------------------------
 */
#include "postgres.h"

#include <ctype.h>

#include "access/htup_details.h"
#include "catalog/catalog.h"
#include "catalog/namespace.h"
#include "catalog/pg_auth_members.h"
#include "catalog/pg_authid.h"
#include "catalog/pg_class.h"
#include "catalog/pg_database.h"
#include "catalog/pg_foreign_data_wrapper.h"
#include "catalog/pg_foreign_server.h"
#include "catalog/pg_language.h"
#include "catalog/pg_largeobject.h"
#include "catalog/pg_namespace.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_tablespace.h"
#include "catalog/pg_type.h"
#include "commands/dbcommands.h"
#include "commands/proclang.h"
#include "commands/tablespace.h"
#include "common/hashfn.h"
#include "foreign/foreign.h"
#include "funcapi.h"
#include "lib/bloomfilter.h"
#include "lib/qunique.h"
#include "miscadmin.h"
#include "storage/large_object.h"
#include "utils/acl.h"
#include "utils/array.h"
#include "utils/builtins.h"
#include "utils/catcache.h"
#include "utils/inval.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"
#include "utils/varlena.h"

typedef struct
{
        const char *name;
        AclMode         value;
} priv_map;

/*
 * We frequently need to test whether a given role is a member of some other
 * role.  In most of these tests the "given role" is the same, namely the
 * active current user.  So we can optimize it by keeping cached lists of all
 * the roles the "given role" is a member of, directly or indirectly.
 *
 * Possibly this mechanism should be generalized to allow caching membership
 * info for multiple roles?
 *
 * Each element of cached_roles is an OID list of constituent roles for the
 * corresponding element of cached_role (always including the cached_role
 * itself).  There's a separate cache for each RoleRecurseType, with the
 * corresponding semantics.
 */
enum RoleRecurseType
{
        ROLERECURSE_MEMBERS = 0,        /* recurse unconditionally */
        ROLERECURSE_PRIVS = 1,          /* recurse through inheritable grants */
        ROLERECURSE_SETROLE = 2         /* recurse through grants with set_option */
};
static Oid      cached_role[] = {InvalidOid, InvalidOid, InvalidOid};
static List *cached_roles[] = {NIL, NIL, NIL};
static uint32 cached_db_hash;

/*
 * If the list of roles gathered by roles_is_member_of() grows larger than the
 * below threshold, a Bloom filter is created to speed up list membership
 * checks.  This threshold is set arbitrarily high to avoid the overhead of
 * creating the Bloom filter until it seems likely to provide a net benefit.
 */
#define ROLES_LIST_BLOOM_THRESHOLD 1024

static const char *getid(const char *s, char *n, Node *escontext);
static void putid(char *p, const char *s);
static Acl *allocacl(int n);
static void check_acl(const Acl *acl);
static const char *aclparse(const char *s, AclItem *aip, Node *escontext);
static bool aclitem_match(const AclItem *a1, const AclItem *a2);
static int      aclitemComparator(const void *arg1, const void *arg2);
static void check_circularity(const Acl *old_acl, const AclItem *mod_aip,
                                                          Oid ownerId);
static Acl *recursive_revoke(Acl *acl, Oid grantee, AclMode revoke_privs,
                                                         Oid ownerId, DropBehavior behavior);

static AclMode convert_any_priv_string(text *priv_type_text,
                                                                           const priv_map *privileges);

static Oid      convert_table_name(text *tablename);
static AclMode convert_table_priv_string(text *priv_type_text);
static AclMode convert_sequence_priv_string(text *priv_type_text);
static AttrNumber convert_column_name(Oid tableoid, text *column);
static AclMode convert_column_priv_string(text *priv_type_text);
static Oid      convert_database_name(text *databasename);
static AclMode convert_database_priv_string(text *priv_type_text);
static Oid      convert_foreign_data_wrapper_name(text *fdwname);
static AclMode convert_foreign_data_wrapper_priv_string(text *priv_type_text);
static Oid      convert_function_name(text *functionname);
static AclMode convert_function_priv_string(text *priv_type_text);
static Oid      convert_language_name(text *languagename);
static AclMode convert_language_priv_string(text *priv_type_text);
static Oid      convert_schema_name(text *schemaname);
static AclMode convert_schema_priv_string(text *priv_type_text);
static Oid      convert_server_name(text *servername);
static AclMode convert_server_priv_string(text *priv_type_text);
static Oid      convert_tablespace_name(text *tablespacename);
static AclMode convert_tablespace_priv_string(text *priv_type_text);
static Oid      convert_type_name(text *typename);
static AclMode convert_type_priv_string(text *priv_type_text);
static AclMode convert_parameter_priv_string(text *priv_text);
static AclMode convert_largeobject_priv_string(text *priv_text);
static AclMode convert_role_priv_string(text *priv_type_text);
static AclResult pg_role_aclcheck(Oid role_oid, Oid roleid, AclMode mode);

static void RoleMembershipCacheCallback(Datum arg, int cacheid, uint32 hashvalue);


/*
 * getid
 *              Consumes the first alphanumeric string (identifier) found in string
 *              's', ignoring any leading white space.  If it finds a double quote
 *              it returns the word inside the quotes.
 *
 * RETURNS:
 *              the string position in 's' that points to the next non-space character
 *              in 's', after any quotes.  Also:
 *              - loads the identifier into 'n'.  (If no identifier is found, 'n'
 *                contains an empty string.)  'n' must be NAMEDATALEN bytes.
 *
 * Errors are reported via ereport, unless escontext is an ErrorSaveData node,
 * in which case we log the error there and return NULL.
 */
static const char *
getid(const char *s, char *n, Node *escontext)
{
        int                     len = 0;
        bool            in_quotes = false;

        Assert(s && n);

        while (isspace((unsigned char) *s))
                s++;
        /* This code had better match what putid() does, below */
        for (;
                 *s != '\0' &&
                 (isalnum((unsigned char) *s) ||
                  *s == '_' ||
                  *s == '"' ||
                  in_quotes);
                 s++)
        {
                if (*s == '"')
                {
                        /* safe to look at next char (could be '\0' though) */
                        if (*(s + 1) != '"')
                        {
                                in_quotes = !in_quotes;
                                continue;
                        }
                        /* it's an escaped double quote; skip the escaping char */
                        s++;
                }

                /* Add the character to the string */
                if (len >= NAMEDATALEN - 1)
                        ereturn(escontext, NULL,
                                        (errcode(ERRCODE_NAME_TOO_LONG),
                                         errmsg("identifier too long"),
                                         errdetail("Identifier must be less than %d characters.",
                                                           NAMEDATALEN)));

                n[len++] = *s;
        }
        n[len] = '\0';
        while (isspace((unsigned char) *s))
                s++;
        return s;
}

/*
 * Write a role name at *p, adding double quotes if needed.
 * There must be at least (2*NAMEDATALEN)+2 bytes available at *p.
 * This needs to be kept in sync with dequoteAclUserName in pg_dump/dumputils.c
 */
static void
putid(char *p, const char *s)
{
        const char *src;
        bool            safe = true;

        for (src = s; *src; src++)
        {
                /* This test had better match what getid() does, above */
                if (!isalnum((unsigned char) *src) && *src != '_')
                {
                        safe = false;
                        break;
                }
        }
        if (!safe)
                *p++ = '"';
        for (src = s; *src; src++)
        {
                /* A double quote character in a username is encoded as "" */
                if (*src == '"')
                        *p++ = '"';
                *p++ = *src;
        }
        if (!safe)
                *p++ = '"';
        *p = '\0';
}

/*
 * aclparse
 *              Consumes and parses an ACL specification of the form:
 *                              [group|user] [A-Za-z0-9]*=[rwaR]*
 *              from string 's', ignoring any leading white space or white space
 *              between the optional id type keyword (group|user) and the actual
 *              ACL specification.
 *
 *              The group|user decoration is unnecessary in the roles world,
 *              but we still accept it for backward compatibility.
 *
 *              This routine is called by the parser as well as aclitemin(), hence
 *              the added generality.
 *
 * RETURNS:
 *              the string position in 's' immediately following the ACL
 *              specification.  Also:
 *              - loads the structure pointed to by 'aip' with the appropriate
 *                UID/GID, id type identifier and mode type values.
 *
 * Errors are reported via ereport, unless escontext is an ErrorSaveData node,
 * in which case we log the error there and return NULL.
 */
static const char *
aclparse(const char *s, AclItem *aip, Node *escontext)
{
        AclMode         privs,
                                goption,
                                read;
        char            name[NAMEDATALEN];
        char            name2[NAMEDATALEN];

        Assert(s && aip);

        s = getid(s, name, escontext);
        if (s == NULL)
                return NULL;
        if (*s != '=')
        {
                /* we just read a keyword, not a name */
                if (strcmp(name, "group") != 0 && strcmp(name, "user") != 0)
                        ereturn(escontext, NULL,
                                        (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
                                         errmsg("unrecognized key word: \"%s\"", name),
                                         errhint("ACL key word must be \"group\" or \"user\".")));
                /* move s to the name beyond the keyword */
                s = getid(s, name, escontext);
                if (s == NULL)
                        return NULL;
                if (name[0] == '\0')
                        ereturn(escontext, NULL,
                                        (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
                                         errmsg("missing name"),
                                         errhint("A name must follow the \"group\" or \"user\" key word.")));
        }

        if (*s != '=')
                ereturn(escontext, NULL,
                                (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
                                 errmsg("missing \"=\" sign")));

        privs = goption = ACL_NO_RIGHTS;

        for (++s, read = 0; isalpha((unsigned char) *s) || *s == '*'; s++)
        {
                switch (*s)
                {
                        case '*':
                                goption |= read;
                                break;
                        case ACL_INSERT_CHR:
                                read = ACL_INSERT;
                                break;
                        case ACL_SELECT_CHR:
                                read = ACL_SELECT;
                                break;
                        case ACL_UPDATE_CHR:
                                read = ACL_UPDATE;
                                break;
                        case ACL_DELETE_CHR:
                                read = ACL_DELETE;
                                break;
                        case ACL_TRUNCATE_CHR:
                                read = ACL_TRUNCATE;
                                break;
                        case ACL_REFERENCES_CHR:
                                read = ACL_REFERENCES;
                                break;
                        case ACL_TRIGGER_CHR:
                                read = ACL_TRIGGER;
                                break;
                        case ACL_EXECUTE_CHR:
                                read = ACL_EXECUTE;
                                break;
                        case ACL_USAGE_CHR:
                                read = ACL_USAGE;
                                break;
                        case ACL_CREATE_CHR:
                                read = ACL_CREATE;
                                break;
                        case ACL_CREATE_TEMP_CHR:
                                read = ACL_CREATE_TEMP;
                                break;
                        case ACL_CONNECT_CHR:
                                read = ACL_CONNECT;
                                break;
                        case ACL_SET_CHR:
                                read = ACL_SET;
                                break;
                        case ACL_ALTER_SYSTEM_CHR:
                                read = ACL_ALTER_SYSTEM;
                                break;
                        case ACL_MAINTAIN_CHR:
                                read = ACL_MAINTAIN;
                                break;
                        default:
                                ereturn(escontext, NULL,
                                                (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
                                                 errmsg("invalid mode character: must be one of \"%s\"",
                                                                ACL_ALL_RIGHTS_STR)));
                }

                privs |= read;
        }

        if (name[0] == '\0')
                aip->ai_grantee = ACL_ID_PUBLIC;
        else
        {
                aip->ai_grantee = get_role_oid(name, true);
                if (!OidIsValid(aip->ai_grantee))
                        ereturn(escontext, NULL,
                                        (errcode(ERRCODE_UNDEFINED_OBJECT),
                                         errmsg("role \"%s\" does not exist", name)));
        }

        /*
         * XXX Allow a degree of backward compatibility by defaulting the grantor
         * to the superuser.
         */
        if (*s == '/')
        {
                s = getid(s + 1, name2, escontext);
                if (s == NULL)
                        return NULL;
                if (name2[0] == '\0')
                        ereturn(escontext, NULL,
                                        (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
                                         errmsg("a name must follow the \"/\" sign")));
                aip->ai_grantor = get_role_oid(name2, true);
                if (!OidIsValid(aip->ai_grantor))
                        ereturn(escontext, NULL,
                                        (errcode(ERRCODE_UNDEFINED_OBJECT),
                                         errmsg("role \"%s\" does not exist", name2)));
        }
        else
        {
                aip->ai_grantor = BOOTSTRAP_SUPERUSERID;
                ereport(WARNING,
                                (errcode(ERRCODE_INVALID_GRANTOR),
                                 errmsg("defaulting grantor to user ID %u",
                                                BOOTSTRAP_SUPERUSERID)));
        }

        ACLITEM_SET_PRIVS_GOPTIONS(*aip, privs, goption);

        return s;
}

/*
 * allocacl
 *              Allocates storage for a new Acl with 'n' entries.
 *
 * RETURNS:
 *              the new Acl
 */
static Acl *
allocacl(int n)
{
        Acl                *new_acl;
        Size            size;

        if (n < 0)
                elog(ERROR, "invalid size: %d", n);
        size = ACL_N_SIZE(n);
        new_acl = (Acl *) palloc0(size);
        SET_VARSIZE(new_acl, size);
        new_acl->ndim = 1;
        new_acl->dataoffset = 0;        /* we never put in any nulls */
        new_acl->elemtype = ACLITEMOID;
        ARR_LBOUND(new_acl)[0] = 1;
        ARR_DIMS(new_acl)[0] = n;
        return new_acl;
}

/*
 * Create a zero-entry ACL
 */
Acl *
make_empty_acl(void)
{
        return allocacl(0);
}

/*
 * Copy an ACL
 */
Acl *
aclcopy(const Acl *orig_acl)
{
        Acl                *result_acl;

        result_acl = allocacl(ACL_NUM(orig_acl));

        memcpy(ACL_DAT(result_acl),
                   ACL_DAT(orig_acl),
                   ACL_NUM(orig_acl) * sizeof(AclItem));

        return result_acl;
}

/*
 * Concatenate two ACLs
 *
 * This is a bit cheesy, since we may produce an ACL with redundant entries.
 * Be careful what the result is used for!
 */
Acl *
aclconcat(const Acl *left_acl, const Acl *right_acl)
{
        Acl                *result_acl;

        result_acl = allocacl(ACL_NUM(left_acl) + ACL_NUM(right_acl));

        memcpy(ACL_DAT(result_acl),
                   ACL_DAT(left_acl),
                   ACL_NUM(left_acl) * sizeof(AclItem));

        memcpy(ACL_DAT(result_acl) + ACL_NUM(left_acl),
                   ACL_DAT(right_acl),
                   ACL_NUM(right_acl) * sizeof(AclItem));

        return result_acl;
}

/*
 * Merge two ACLs
 *
 * This produces a properly merged ACL with no redundant entries.
 * Returns NULL on NULL input.
 */
Acl *
aclmerge(const Acl *left_acl, const Acl *right_acl, Oid ownerId)
{
        Acl                *result_acl;
        AclItem    *aip;
        int                     i,
                                num;

        /* Check for cases where one or both are empty/null */
        if (left_acl == NULL || ACL_NUM(left_acl) == 0)
        {
                if (right_acl == NULL || ACL_NUM(right_acl) == 0)
                        return NULL;
                else
                        return aclcopy(right_acl);
        }
        else
        {
                if (right_acl == NULL || ACL_NUM(right_acl) == 0)
                        return aclcopy(left_acl);
        }

        /* Merge them the hard way, one item at a time */
        result_acl = aclcopy(left_acl);

        aip = ACL_DAT(right_acl);
        num = ACL_NUM(right_acl);

        for (i = 0; i < num; i++, aip++)
        {
                Acl                *tmp_acl;

                tmp_acl = aclupdate(result_acl, aip, ACL_MODECHG_ADD,
                                                        ownerId, DROP_RESTRICT);
                pfree(result_acl);
                result_acl = tmp_acl;
        }

        return result_acl;
}

/*
 * Sort the items in an ACL (into an arbitrary but consistent order)
 */
void
aclitemsort(Acl *acl)
{
        if (acl != NULL && ACL_NUM(acl) > 1)
                qsort(ACL_DAT(acl), ACL_NUM(acl), sizeof(AclItem), aclitemComparator);
}

/*
 * Check if two ACLs are exactly equal
 *
 * This will not detect equality if the two arrays contain the same items
 * in different orders.  To handle that case, sort both inputs first,
 * using aclitemsort().
 */
bool
aclequal(const Acl *left_acl, const Acl *right_acl)
{
        /* Check for cases where one or both are empty/null */
        if (left_acl == NULL || ACL_NUM(left_acl) == 0)
        {
                if (right_acl == NULL || ACL_NUM(right_acl) == 0)
                        return true;
                else
                        return false;
        }
        else
        {
                if (right_acl == NULL || ACL_NUM(right_acl) == 0)
                        return false;
        }

        if (ACL_NUM(left_acl) != ACL_NUM(right_acl))
                return false;

        if (memcmp(ACL_DAT(left_acl),
                           ACL_DAT(right_acl),
                           ACL_NUM(left_acl) * sizeof(AclItem)) == 0)
                return true;

        return false;
}

/*
 * Verify that an ACL array is acceptable (one-dimensional and has no nulls)
 */
static void
check_acl(const Acl *acl)
{
        if (ARR_ELEMTYPE(acl) != ACLITEMOID)
                ereport(ERROR,
                                (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                                 errmsg("ACL array contains wrong data type")));
        if (ARR_NDIM(acl) != 1)
                ereport(ERROR,
                                (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                                 errmsg("ACL arrays must be one-dimensional")));
        if (ARR_HASNULL(acl))
                ereport(ERROR,
                                (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                                 errmsg("ACL arrays must not contain null values")));
}

/*
 * aclitemin
 *              Allocates storage for, and fills in, a new AclItem given a string
 *              's' that contains an ACL specification.  See aclparse for details.
 *
 * RETURNS:
 *              the new AclItem
 */
Datum
aclitemin(PG_FUNCTION_ARGS)
{
        const char *s = PG_GETARG_CSTRING(0);
        Node       *escontext = fcinfo->context;
        AclItem    *aip;

        aip = (AclItem *) palloc(sizeof(AclItem));

        s = aclparse(s, aip, escontext);
        if (s == NULL)
                PG_RETURN_NULL();

        while (isspace((unsigned char) *s))
                ++s;
        if (*s)
                ereturn(escontext, (Datum) 0,
                                (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
                                 errmsg("extra garbage at the end of the ACL specification")));

        PG_RETURN_ACLITEM_P(aip);
}

/*
 * aclitemout
 *              Allocates storage for, and fills in, a new null-delimited string
 *              containing a formatted ACL specification.  See aclparse for details.
 *
 * RETURNS:
 *              the new string
 */
Datum
aclitemout(PG_FUNCTION_ARGS)
{
        AclItem    *aip = PG_GETARG_ACLITEM_P(0);
        char       *p;
        char       *out;
        HeapTuple       htup;
        unsigned        i;

        out = palloc(strlen("=/") +
                                 2 * N_ACL_RIGHTS +
                                 2 * (2 * NAMEDATALEN + 2) +
                                 1);

        p = out;
        *p = '\0';

        if (aip->ai_grantee != ACL_ID_PUBLIC)
        {
                htup = SearchSysCache1(AUTHOID, ObjectIdGetDatum(aip->ai_grantee));
                if (HeapTupleIsValid(htup))
                {
                        putid(p, NameStr(((Form_pg_authid) GETSTRUCT(htup))->rolname));
                        ReleaseSysCache(htup);
                }
                else
                {
                        /* Generate numeric OID if we don't find an entry */
                        sprintf(p, "%u", aip->ai_grantee);
                }
        }
        while (*p)
                ++p;

        *p++ = '=';

        for (i = 0; i < N_ACL_RIGHTS; ++i)
        {
                if (ACLITEM_GET_PRIVS(*aip) & (UINT64CONST(1) << i))
                        *p++ = ACL_ALL_RIGHTS_STR[i];
                if (ACLITEM_GET_GOPTIONS(*aip) & (UINT64CONST(1) << i))
                        *p++ = '*';
        }

        *p++ = '/';
        *p = '\0';

        htup = SearchSysCache1(AUTHOID, ObjectIdGetDatum(aip->ai_grantor));
        if (HeapTupleIsValid(htup))
        {
                putid(p, NameStr(((Form_pg_authid) GETSTRUCT(htup))->rolname));
                ReleaseSysCache(htup);
        }
        else
        {
                /* Generate numeric OID if we don't find an entry */
                sprintf(p, "%u", aip->ai_grantor);
        }

        PG_RETURN_CSTRING(out);
}

/*
 * aclitem_match
 *              Two AclItems are considered to match iff they have the same
 *              grantee and grantor; the privileges are ignored.
 */
static bool
aclitem_match(const AclItem *a1, const AclItem *a2)
{
        return a1->ai_grantee == a2->ai_grantee &&
                a1->ai_grantor == a2->ai_grantor;
}

/*
 * aclitemComparator
 *              qsort comparison function for AclItems
 */
static int
aclitemComparator(const void *arg1, const void *arg2)
{
        const AclItem *a1 = (const AclItem *) arg1;
        const AclItem *a2 = (const AclItem *) arg2;

        if (a1->ai_grantee > a2->ai_grantee)
                return 1;
        if (a1->ai_grantee < a2->ai_grantee)
                return -1;
        if (a1->ai_grantor > a2->ai_grantor)
                return 1;
        if (a1->ai_grantor < a2->ai_grantor)
                return -1;
        if (a1->ai_privs > a2->ai_privs)
                return 1;
        if (a1->ai_privs < a2->ai_privs)
                return -1;
        return 0;
}

/*
 * aclitem equality operator
 */
Datum
aclitem_eq(PG_FUNCTION_ARGS)
{
        AclItem    *a1 = PG_GETARG_ACLITEM_P(0);
        AclItem    *a2 = PG_GETARG_ACLITEM_P(1);
        bool            result;

        result = a1->ai_privs == a2->ai_privs &&
                a1->ai_grantee == a2->ai_grantee &&
                a1->ai_grantor == a2->ai_grantor;
        PG_RETURN_BOOL(result);
}

/*
 * aclitem hash function
 *
 * We make aclitems hashable not so much because anyone is likely to hash
 * them, as because we want array equality to work on aclitem arrays, and
 * with the typcache mechanism we must have a hash or btree opclass.
 */
Datum
hash_aclitem(PG_FUNCTION_ARGS)
{
        AclItem    *a = PG_GETARG_ACLITEM_P(0);

        /* not very bright, but avoids any issue of padding in struct */
        PG_RETURN_UINT32((uint32) (a->ai_privs + a->ai_grantee + a->ai_grantor));
}

/*
 * 64-bit hash function for aclitem.
 *
 * Similar to hash_aclitem, but accepts a seed and returns a uint64 value.
 */
Datum
hash_aclitem_extended(PG_FUNCTION_ARGS)
{
        AclItem    *a = PG_GETARG_ACLITEM_P(0);
        uint64          seed = PG_GETARG_INT64(1);
        uint32          sum = (uint32) (a->ai_privs + a->ai_grantee + a->ai_grantor);

        return (seed == 0) ? UInt64GetDatum(sum) : hash_uint32_extended(sum, seed);
}

/*
 * acldefault()  --- create an ACL describing default access permissions
 *
 * Change this routine if you want to alter the default access policy for
 * newly-created objects (or any object with a NULL acl entry).  When
 * you make a change here, don't forget to update the GRANT man page,
 * which explains all the default permissions.
 *
 * Note that these are the hard-wired "defaults" that are used in the
 * absence of any pg_default_acl entry.
 */
Acl *
acldefault(ObjectType objtype, Oid ownerId)
{
        AclMode         world_default;
        AclMode         owner_default;
        int                     nacl;
        Acl                *acl;
        AclItem    *aip;

        switch (objtype)
        {
                case OBJECT_COLUMN:
                        /* by default, columns have no extra privileges */
                        world_default = ACL_NO_RIGHTS;
                        owner_default = ACL_NO_RIGHTS;
                        break;
                case OBJECT_TABLE:
                        world_default = ACL_NO_RIGHTS;
                        owner_default = ACL_ALL_RIGHTS_RELATION;
                        break;
                case OBJECT_SEQUENCE:
                        world_default = ACL_NO_RIGHTS;
                        owner_default = ACL_ALL_RIGHTS_SEQUENCE;
                        break;
                case OBJECT_DATABASE:
                        /* for backwards compatibility, grant some rights by default */
                        world_default = ACL_CREATE_TEMP | ACL_CONNECT;
                        owner_default = ACL_ALL_RIGHTS_DATABASE;
                        break;
                case OBJECT_FUNCTION:
                        /* Grant EXECUTE by default, for now */
                        world_default = ACL_EXECUTE;
                        owner_default = ACL_ALL_RIGHTS_FUNCTION;
                        break;
                case OBJECT_LANGUAGE:
                        /* Grant USAGE by default, for now */
                        world_default = ACL_USAGE;
                        owner_default = ACL_ALL_RIGHTS_LANGUAGE;
                        break;
                case OBJECT_LARGEOBJECT:
                        world_default = ACL_NO_RIGHTS;
                        owner_default = ACL_ALL_RIGHTS_LARGEOBJECT;
                        break;
                case OBJECT_SCHEMA:
                        world_default = ACL_NO_RIGHTS;
                        owner_default = ACL_ALL_RIGHTS_SCHEMA;
                        break;
                case OBJECT_TABLESPACE:
                        world_default = ACL_NO_RIGHTS;
                        owner_default = ACL_ALL_RIGHTS_TABLESPACE;
                        break;
                case OBJECT_FDW:
                        world_default = ACL_NO_RIGHTS;
                        owner_default = ACL_ALL_RIGHTS_FDW;
                        break;
                case OBJECT_FOREIGN_SERVER:
                        world_default = ACL_NO_RIGHTS;
                        owner_default = ACL_ALL_RIGHTS_FOREIGN_SERVER;
                        break;
                case OBJECT_DOMAIN:
                case OBJECT_TYPE:
                        world_default = ACL_USAGE;
                        owner_default = ACL_ALL_RIGHTS_TYPE;
                        break;
                case OBJECT_PARAMETER_ACL:
                        world_default = ACL_NO_RIGHTS;
                        owner_default = ACL_ALL_RIGHTS_PARAMETER_ACL;
                        break;
                default:
                        elog(ERROR, "unrecognized object type: %d", (int) objtype);
                        world_default = ACL_NO_RIGHTS;  /* keep compiler quiet */
                        owner_default = ACL_NO_RIGHTS;
                        break;
        }

        nacl = 0;
        if (world_default != ACL_NO_RIGHTS)
                nacl++;
        if (owner_default != ACL_NO_RIGHTS)
                nacl++;

        acl = allocacl(nacl);
        aip = ACL_DAT(acl);

        if (world_default != ACL_NO_RIGHTS)
        {
                aip->ai_grantee = ACL_ID_PUBLIC;
                aip->ai_grantor = ownerId;
                ACLITEM_SET_PRIVS_GOPTIONS(*aip, world_default, ACL_NO_RIGHTS);
                aip++;
        }

        /*
         * Note that the owner's entry shows all ordinary privileges but no grant
         * options.  This is because his grant options come "from the system" and
         * not from his own efforts.  (The SQL spec says that the owner's rights
         * come from a "_SYSTEM" authid.)  However, we do consider that the
         * owner's ordinary privileges are self-granted; this lets him revoke
         * them.  We implement the owner's grant options without any explicit
         * "_SYSTEM"-like ACL entry, by internally special-casing the owner
         * wherever we are testing grant options.
         */
        if (owner_default != ACL_NO_RIGHTS)
        {
                aip->ai_grantee = ownerId;
                aip->ai_grantor = ownerId;
                ACLITEM_SET_PRIVS_GOPTIONS(*aip, owner_default, ACL_NO_RIGHTS);
        }

        return acl;
}


/*
 * SQL-accessible version of acldefault().  Hackish mapping from "char" type to
 * OBJECT_* values.
 */
Datum
acldefault_sql(PG_FUNCTION_ARGS)
{
        char            objtypec = PG_GETARG_CHAR(0);
        Oid                     owner = PG_GETARG_OID(1);
        ObjectType      objtype = 0;

        switch (objtypec)
        {
                case 'c':
                        objtype = OBJECT_COLUMN;
                        break;
                case 'r':
                        objtype = OBJECT_TABLE;
                        break;
                case 's':
                        objtype = OBJECT_SEQUENCE;
                        break;
                case 'd':
                        objtype = OBJECT_DATABASE;
                        break;
                case 'f':
                        objtype = OBJECT_FUNCTION;
                        break;
                case 'l':
                        objtype = OBJECT_LANGUAGE;
                        break;
                case 'L':
                        objtype = OBJECT_LARGEOBJECT;
                        break;
                case 'n':
                        objtype = OBJECT_SCHEMA;
                        break;
                case 'p':
                        objtype = OBJECT_PARAMETER_ACL;
                        break;
                case 't':
                        objtype = OBJECT_TABLESPACE;
                        break;
                case 'F':
                        objtype = OBJECT_FDW;
                        break;
                case 'S':
                        objtype = OBJECT_FOREIGN_SERVER;
                        break;
                case 'T':
                        objtype = OBJECT_TYPE;
                        break;
                default:
                        elog(ERROR, "unrecognized object type abbreviation: %c", objtypec);
        }

        PG_RETURN_ACL_P(acldefault(objtype, owner));
}


/*
 * Update an ACL array to add or remove specified privileges.
 *
 *      old_acl: the input ACL array
 *      mod_aip: defines the privileges to be added, removed, or substituted
 *      modechg: ACL_MODECHG_ADD, ACL_MODECHG_DEL, or ACL_MODECHG_EQL
 *      ownerId: Oid of object owner
 *      behavior: RESTRICT or CASCADE behavior for recursive removal
 *
 * ownerid and behavior are only relevant when the update operation specifies
 * deletion of grant options.
 *
 * The result is a modified copy; the input object is not changed.
 *
 * NB: caller is responsible for having detoasted the input ACL, if needed.
 */
Acl *
aclupdate(const Acl *old_acl, const AclItem *mod_aip,
                  int modechg, Oid ownerId, DropBehavior behavior)
{
        Acl                *new_acl = NULL;
        AclItem    *old_aip,
                           *new_aip = NULL;
        AclMode         old_rights,
                                old_goptions,
                                new_rights,
                                new_goptions;
        int                     dst,
                                num;

        /* Caller probably already checked old_acl, but be safe */
        check_acl(old_acl);

        /* If granting grant options, check for circularity */
        if (modechg != ACL_MODECHG_DEL &&
                ACLITEM_GET_GOPTIONS(*mod_aip) != ACL_NO_RIGHTS)
                check_circularity(old_acl, mod_aip, ownerId);

        num = ACL_NUM(old_acl);
        old_aip = ACL_DAT(old_acl);

        /*
         * Search the ACL for an existing entry for this grantee and grantor. If
         * one exists, just modify the entry in-place (well, in the same position,
         * since we actually return a copy); otherwise, insert the new entry at
         * the end.
         */

        for (dst = 0; dst < num; ++dst)
        {
                if (aclitem_match(mod_aip, old_aip + dst))
                {
                        /* found a match, so modify existing item */
                        new_acl = allocacl(num);
                        new_aip = ACL_DAT(new_acl);
                        memcpy(new_acl, old_acl, ACL_SIZE(old_acl));
                        break;
                }
        }

        if (dst == num)
        {
                /* need to append a new item */
                new_acl = allocacl(num + 1);
                new_aip = ACL_DAT(new_acl);
                memcpy(new_aip, old_aip, num * sizeof(AclItem));

                /* initialize the new entry with no permissions */
                new_aip[dst].ai_grantee = mod_aip->ai_grantee;
                new_aip[dst].ai_grantor = mod_aip->ai_grantor;
                ACLITEM_SET_PRIVS_GOPTIONS(new_aip[dst],
                                                                   ACL_NO_RIGHTS, ACL_NO_RIGHTS);
                num++;                                  /* set num to the size of new_acl */
        }

        old_rights = ACLITEM_GET_RIGHTS(new_aip[dst]);
        old_goptions = ACLITEM_GET_GOPTIONS(new_aip[dst]);

        /* apply the specified permissions change */
        switch (modechg)
        {
                case ACL_MODECHG_ADD:
                        ACLITEM_SET_RIGHTS(new_aip[dst],
                                                           old_rights | ACLITEM_GET_RIGHTS(*mod_aip));
                        break;
                case ACL_MODECHG_DEL:
                        ACLITEM_SET_RIGHTS(new_aip[dst],
                                                           old_rights & ~ACLITEM_GET_RIGHTS(*mod_aip));
                        break;
                case ACL_MODECHG_EQL:
                        ACLITEM_SET_RIGHTS(new_aip[dst],
                                                           ACLITEM_GET_RIGHTS(*mod_aip));
                        break;
        }

        new_rights = ACLITEM_GET_RIGHTS(new_aip[dst]);
        new_goptions = ACLITEM_GET_GOPTIONS(new_aip[dst]);

        /*
         * If the adjusted entry has no permissions, delete it from the list.
         */
        if (new_rights == ACL_NO_RIGHTS)
        {
                memmove(new_aip + dst,
                                new_aip + dst + 1,
                                (num - dst - 1) * sizeof(AclItem));
                /* Adjust array size to be 'num - 1' items */
                ARR_DIMS(new_acl)[0] = num - 1;
                SET_VARSIZE(new_acl, ACL_N_SIZE(num - 1));
        }

        /*
         * Remove abandoned privileges (cascading revoke).  Currently we can only
         * handle this when the grantee is not PUBLIC.
         */
        if ((old_goptions & ~new_goptions) != 0)
        {
                Assert(mod_aip->ai_grantee != ACL_ID_PUBLIC);
                new_acl = recursive_revoke(new_acl, mod_aip->ai_grantee,
                                                                   (old_goptions & ~new_goptions),
                                                                   ownerId, behavior);
        }

        return new_acl;
}

/*
 * Update an ACL array to reflect a change of owner to the parent object
 *
 *      old_acl: the input ACL array (must not be NULL)
 *      oldOwnerId: Oid of the old object owner
 *      newOwnerId: Oid of the new object owner
 *
 * The result is a modified copy; the input object is not changed.
 *
 * NB: caller is responsible for having detoasted the input ACL, if needed.
 *
 * Note: the name of this function is a bit of a misnomer, since it will
 * happily make the specified role substitution whether the old role is
 * really the owner of the parent object or merely mentioned in its ACL.
 * But the vast majority of callers use it in connection with ALTER OWNER
 * operations, so we'll keep the name.
 */
Acl *
aclnewowner(const Acl *old_acl, Oid oldOwnerId, Oid newOwnerId)
{
        Acl                *new_acl;
        AclItem    *new_aip;
        AclItem    *old_aip;
        AclItem    *dst_aip;
        AclItem    *src_aip;
        AclItem    *targ_aip;
        bool            newpresent = false;
        int                     dst,
                                src,
                                targ,
                                num;

        check_acl(old_acl);

        /*
         * Make a copy of the given ACL, substituting new owner ID for old
         * wherever it appears as either grantor or grantee.  Also note if the new
         * owner ID is already present.
         */
        num = ACL_NUM(old_acl);
        old_aip = ACL_DAT(old_acl);
        new_acl = allocacl(num);
        new_aip = ACL_DAT(new_acl);
        memcpy(new_aip, old_aip, num * sizeof(AclItem));
        for (dst = 0, dst_aip = new_aip; dst < num; dst++, dst_aip++)
        {
                if (dst_aip->ai_grantor == oldOwnerId)
                        dst_aip->ai_grantor = newOwnerId;
                else if (dst_aip->ai_grantor == newOwnerId)
                        newpresent = true;
                if (dst_aip->ai_grantee == oldOwnerId)
                        dst_aip->ai_grantee = newOwnerId;
                else if (dst_aip->ai_grantee == newOwnerId)
                        newpresent = true;
        }

        /*
         * If the old ACL contained any references to the new owner, then we may
         * now have generated an ACL containing duplicate entries.  Find them and
         * merge them so that there are not duplicates.  (This is relatively
         * expensive since we use a stupid O(N^2) algorithm, but it's unlikely to
         * be the normal case.)
         *
         * To simplify deletion of duplicate entries, we temporarily leave them in
         * the array but set their privilege masks to zero; when we reach such an
         * entry it's just skipped.  (Thus, a side effect of this code will be to
         * remove privilege-free entries, should there be any in the input.)  dst
         * is the next output slot, targ is the currently considered input slot
         * (always >= dst), and src scans entries to the right of targ looking for
         * duplicates.  Once an entry has been emitted to dst it is known
         * duplicate-free and need not be considered anymore.
         */
        if (newpresent)
        {
                dst = 0;
                for (targ = 0, targ_aip = new_aip; targ < num; targ++, targ_aip++)
                {
                        /* ignore if deleted in an earlier pass */
                        if (ACLITEM_GET_RIGHTS(*targ_aip) == ACL_NO_RIGHTS)
                                continue;
                        /* find and merge any duplicates */
                        for (src = targ + 1, src_aip = targ_aip + 1; src < num;
                                 src++, src_aip++)
                        {
                                if (ACLITEM_GET_RIGHTS(*src_aip) == ACL_NO_RIGHTS)
                                        continue;
                                if (aclitem_match(targ_aip, src_aip))
                                {
                                        ACLITEM_SET_RIGHTS(*targ_aip,
                                                                           ACLITEM_GET_RIGHTS(*targ_aip) |
                                                                           ACLITEM_GET_RIGHTS(*src_aip));
                                        /* mark the duplicate deleted */
                                        ACLITEM_SET_RIGHTS(*src_aip, ACL_NO_RIGHTS);
                                }
                        }
                        /* and emit to output */
                        new_aip[dst] = *targ_aip;
                        dst++;
                }
                /* Adjust array size to be 'dst' items */
                ARR_DIMS(new_acl)[0] = dst;
                SET_VARSIZE(new_acl, ACL_N_SIZE(dst));
        }

        return new_acl;
}


/*
 * When granting grant options, we must disallow attempts to set up circular
 * chains of grant options.  Suppose A (the object owner) grants B some
 * privileges with grant option, and B re-grants them to C.  If C could
 * grant the privileges to B as well, then A would be unable to effectively
 * revoke the privileges from B, since recursive_revoke would consider that
 * B still has 'em from C.
 *
 * We check for this by recursively deleting all grant options belonging to
 * the target grantee, and then seeing if the would-be grantor still has the
 * grant option or not.
 */
static void
check_circularity(const Acl *old_acl, const AclItem *mod_aip,
                                  Oid ownerId)
{
        Acl                *acl;
        AclItem    *aip;
        int                     i,
                                num;
        AclMode         own_privs;

        check_acl(old_acl);

        /*
         * For now, grant options can only be granted to roles, not PUBLIC.
         * Otherwise we'd have to work a bit harder here.
         */
        Assert(mod_aip->ai_grantee != ACL_ID_PUBLIC);

        /* The owner always has grant options, no need to check */
        if (mod_aip->ai_grantor == ownerId)
                return;

        /* Make a working copy */
        acl = allocacl(ACL_NUM(old_acl));
        memcpy(acl, old_acl, ACL_SIZE(old_acl));

        /* Zap all grant options of target grantee, plus what depends on 'em */
cc_restart:
        num = ACL_NUM(acl);
        aip = ACL_DAT(acl);
        for (i = 0; i < num; i++)
        {
                if (aip[i].ai_grantee == mod_aip->ai_grantee &&
                        ACLITEM_GET_GOPTIONS(aip[i]) != ACL_NO_RIGHTS)
                {
                        Acl                *new_acl;

                        /* We'll actually zap ordinary privs too, but no matter */
                        new_acl = aclupdate(acl, &aip[i], ACL_MODECHG_DEL,
                                                                ownerId, DROP_CASCADE);

                        pfree(acl);
                        acl = new_acl;

                        goto cc_restart;
                }
        }

        /* Now we can compute grantor's independently-derived privileges */
        own_privs = aclmask(acl,
                                                mod_aip->ai_grantor,
                                                ownerId,
                                                ACL_GRANT_OPTION_FOR(ACLITEM_GET_GOPTIONS(*mod_aip)),
                                                ACLMASK_ALL);
        own_privs = ACL_OPTION_TO_PRIVS(own_privs);

        if ((ACLITEM_GET_GOPTIONS(*mod_aip) & ~own_privs) != 0)
                ereport(ERROR,
                                (errcode(ERRCODE_INVALID_GRANT_OPERATION),
                                 errmsg("grant options cannot be granted back to your own grantor")));

        pfree(acl);
}


/*
 * Ensure that no privilege is "abandoned".  A privilege is abandoned
 * if the user that granted the privilege loses the grant option.  (So
 * the chain through which it was granted is broken.)  Either the
 * abandoned privileges are revoked as well, or an error message is
 * printed, depending on the drop behavior option.
 *
 *      acl: the input ACL list
 *      grantee: the user from whom some grant options have been revoked
 *      revoke_privs: the grant options being revoked
 *      ownerId: Oid of object owner
 *      behavior: RESTRICT or CASCADE behavior for recursive removal
 *
 * The input Acl object is pfree'd if replaced.
 */
static Acl *
recursive_revoke(Acl *acl,
                                 Oid grantee,
                                 AclMode revoke_privs,
                                 Oid ownerId,
                                 DropBehavior behavior)
{
        AclMode         still_has;
        AclItem    *aip;
        int                     i,
                                num;

        check_acl(acl);

        /* The owner can never truly lose grant options, so short-circuit */
        if (grantee == ownerId)
                return acl;

        /* The grantee might still have some grant options via another grantor */
        still_has = aclmask(acl, grantee, ownerId,
                                                ACL_GRANT_OPTION_FOR(revoke_privs),
                                                ACLMASK_ALL);
        revoke_privs &= ~ACL_OPTION_TO_PRIVS(still_has);
        if (revoke_privs == ACL_NO_RIGHTS)
                return acl;

restart:
        num = ACL_NUM(acl);
        aip = ACL_DAT(acl);
        for (i = 0; i < num; i++)
        {
                if (aip[i].ai_grantor == grantee
                        && (ACLITEM_GET_PRIVS(aip[i]) & revoke_privs) != 0)
                {
                        AclItem         mod_acl;
                        Acl                *new_acl;

                        if (behavior == DROP_RESTRICT)
                                ereport(ERROR,
                                                (errcode(ERRCODE_DEPENDENT_OBJECTS_STILL_EXIST),
                                                 errmsg("dependent privileges exist"),
                                                 errhint("Use CASCADE to revoke them too.")));

                        mod_acl.ai_grantor = grantee;
                        mod_acl.ai_grantee = aip[i].ai_grantee;
                        ACLITEM_SET_PRIVS_GOPTIONS(mod_acl,
                                                                           revoke_privs,
                                                                           revoke_privs);

                        new_acl = aclupdate(acl, &mod_acl, ACL_MODECHG_DEL,
                                                                ownerId, behavior);

                        pfree(acl);
                        acl = new_acl;

                        goto restart;
                }
        }

        return acl;
}


/*
 * aclmask --- compute bitmask of all privileges held by roleid.
 *
 * When 'how' = ACLMASK_ALL, this simply returns the privilege bits
 * held by the given roleid according to the given ACL list, ANDed
 * with 'mask'.  (The point of passing 'mask' is to let the routine
 * exit early if all privileges of interest have been found.)
 *
 * When 'how' = ACLMASK_ANY, returns as soon as any bit in the mask
 * is known true.  (This lets us exit soonest in cases where the
 * caller is only going to test for zero or nonzero result.)
 *
 * Usage patterns:
 *
 * To see if any of a set of privileges are held:
 *              if (aclmask(acl, roleid, ownerId, privs, ACLMASK_ANY) != 0)
 *
 * To see if all of a set of privileges are held:
 *              if (aclmask(acl, roleid, ownerId, privs, ACLMASK_ALL) == privs)
 *
 * To determine exactly which of a set of privileges are held:
 *              heldprivs = aclmask(acl, roleid, ownerId, privs, ACLMASK_ALL);
 */
AclMode
aclmask(const Acl *acl, Oid roleid, Oid ownerId,
                AclMode mask, AclMaskHow how)
{
        AclMode         result;
        AclMode         remaining;
        AclItem    *aidat;
        int                     i,
                                num;

        /*
         * Null ACL should not happen, since caller should have inserted
         * appropriate default
         */
        if (acl == NULL)
                elog(ERROR, "null ACL");

        check_acl(acl);

        /* Quick exit for mask == 0 */
        if (mask == 0)
                return 0;

        result = 0;

        /* Owner always implicitly has all grant options */
        if ((mask & ACLITEM_ALL_GOPTION_BITS) &&
                has_privs_of_role(roleid, ownerId))
        {
                result = mask & ACLITEM_ALL_GOPTION_BITS;
                if ((how == ACLMASK_ALL) ? (result == mask) : (result != 0))
                        return result;
        }

        num = ACL_NUM(acl);
        aidat = ACL_DAT(acl);

        /*
         * Check privileges granted directly to roleid or to public
         */
        for (i = 0; i < num; i++)
        {
                AclItem    *aidata = &aidat[i];

                if (aidata->ai_grantee == ACL_ID_PUBLIC ||
                        aidata->ai_grantee == roleid)
                {
                        result |= aidata->ai_privs & mask;
                        if ((how == ACLMASK_ALL) ? (result == mask) : (result != 0))
                                return result;
                }
        }

        /*
         * Check privileges granted indirectly via role memberships. We do this in
         * a separate pass to minimize expensive indirect membership tests.  In
         * particular, it's worth testing whether a given ACL entry grants any
         * privileges still of interest before we perform the has_privs_of_role
         * test.
         */
        remaining = mask & ~result;
        for (i = 0; i < num; i++)
        {
                AclItem    *aidata = &aidat[i];

                if (aidata->ai_grantee == ACL_ID_PUBLIC ||
                        aidata->ai_grantee == roleid)
                        continue;                       /* already checked it */

                if ((aidata->ai_privs & remaining) &&
                        has_privs_of_role(roleid, aidata->ai_grantee))
                {
                        result |= aidata->ai_privs & mask;
                        if ((how == ACLMASK_ALL) ? (result == mask) : (result != 0))
                                return result;
                        remaining = mask & ~result;
                }
        }

        return result;
}


/*
 * aclmask_direct --- compute bitmask of all privileges held by roleid.
 *
 * This is exactly like aclmask() except that we consider only privileges
 * held *directly* by roleid, not those inherited via role membership.
 */
static AclMode
aclmask_direct(const Acl *acl, Oid roleid, Oid ownerId,
                           AclMode mask, AclMaskHow how)
{
        AclMode         result;
        AclItem    *aidat;
        int                     i,
                                num;

        /*
         * Null ACL should not happen, since caller should have inserted
         * appropriate default
         */
        if (acl == NULL)
                elog(ERROR, "null ACL");

        check_acl(acl);

        /* Quick exit for mask == 0 */
        if (mask == 0)
                return 0;

        result = 0;

        /* Owner always implicitly has all grant options */
        if ((mask & ACLITEM_ALL_GOPTION_BITS) &&
                roleid == ownerId)
        {
                result = mask & ACLITEM_ALL_GOPTION_BITS;
                if ((how == ACLMASK_ALL) ? (result == mask) : (result != 0))
                        return result;
        }

        num = ACL_NUM(acl);
        aidat = ACL_DAT(acl);

        /*
         * Check privileges granted directly to roleid (and not to public)
         */
        for (i = 0; i < num; i++)
        {
                AclItem    *aidata = &aidat[i];

                if (aidata->ai_grantee == roleid)
                {
                        result |= aidata->ai_privs & mask;
                        if ((how == ACLMASK_ALL) ? (result == mask) : (result != 0))
                                return result;
                }
        }

        return result;
}


/*
 * aclmembers
 *              Find out all the roleids mentioned in an Acl.
 *              Note that we do not distinguish grantors from grantees.
 *
 * *roleids is set to point to a palloc'd array containing distinct OIDs
 * in sorted order.  The length of the array is the function result.
 */
int
aclmembers(const Acl *acl, Oid **roleids)
{
        Oid                *list;
        const AclItem *acldat;
        int                     i,
                                j;

        if (acl == NULL || ACL_NUM(acl) == 0)
        {
                *roleids = NULL;
                return 0;
        }

        check_acl(acl);

        /* Allocate the worst-case space requirement */
        list = palloc(ACL_NUM(acl) * 2 * sizeof(Oid));
        acldat = ACL_DAT(acl);

        /*
         * Walk the ACL collecting mentioned RoleIds.
         */
        j = 0;
        for (i = 0; i < ACL_NUM(acl); i++)
        {
                const AclItem *ai = &acldat[i];

                if (ai->ai_grantee != ACL_ID_PUBLIC)
                        list[j++] = ai->ai_grantee;
                /* grantor is currently never PUBLIC, but let's check anyway */
                if (ai->ai_grantor != ACL_ID_PUBLIC)
                        list[j++] = ai->ai_grantor;
        }

        /* Sort the array */
        qsort(list, j, sizeof(Oid), oid_cmp);

        /*
         * We could repalloc the array down to minimum size, but it's hardly worth
         * it since it's only transient memory.
         */
        *roleids = list;

        /* Remove duplicates from the array */
        return qunique(list, j, sizeof(Oid), oid_cmp);
}


/*
 * aclinsert (exported function)
 */
Datum
aclinsert(PG_FUNCTION_ARGS)
{
        ereport(ERROR,
                        (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                         errmsg("aclinsert is no longer supported")));

        PG_RETURN_NULL();                       /* keep compiler quiet */
}

Datum
aclremove(PG_FUNCTION_ARGS)
{
        ereport(ERROR,
                        (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                         errmsg("aclremove is no longer supported")));

        PG_RETURN_NULL();                       /* keep compiler quiet */
}

Datum
aclcontains(PG_FUNCTION_ARGS)
{
        Acl                *acl = PG_GETARG_ACL_P(0);
        AclItem    *aip = PG_GETARG_ACLITEM_P(1);
        AclItem    *aidat;
        int                     i,
                                num;

        check_acl(acl);
        num = ACL_NUM(acl);
        aidat = ACL_DAT(acl);
        for (i = 0; i < num; ++i)
        {
                if (aip->ai_grantee == aidat[i].ai_grantee &&
                        aip->ai_grantor == aidat[i].ai_grantor &&
                        (ACLITEM_GET_RIGHTS(*aip) & ACLITEM_GET_RIGHTS(aidat[i])) == ACLITEM_GET_RIGHTS(*aip))
                        PG_RETURN_BOOL(true);
        }
        PG_RETURN_BOOL(false);
}

Datum
makeaclitem(PG_FUNCTION_ARGS)
{
        Oid                     grantee = PG_GETARG_OID(0);
        Oid                     grantor = PG_GETARG_OID(1);
        text       *privtext = PG_GETARG_TEXT_PP(2);
        bool            goption = PG_GETARG_BOOL(3);
        AclItem    *result;
        AclMode         priv;
        static const priv_map any_priv_map[] = {
                {"SELECT", ACL_SELECT},
                {"INSERT", ACL_INSERT},
                {"UPDATE", ACL_UPDATE},
                {"DELETE", ACL_DELETE},
                {"TRUNCATE", ACL_TRUNCATE},
                {"REFERENCES", ACL_REFERENCES},
                {"TRIGGER", ACL_TRIGGER},
                {"EXECUTE", ACL_EXECUTE},
                {"USAGE", ACL_USAGE},
                {"CREATE", ACL_CREATE},
                {"TEMP", ACL_CREATE_TEMP},
                {"TEMPORARY", ACL_CREATE_TEMP},
                {"CONNECT", ACL_CONNECT},
                {"SET", ACL_SET},
                {"ALTER SYSTEM", ACL_ALTER_SYSTEM},
                {"MAINTAIN", ACL_MAINTAIN},
                {NULL, 0}
        };

        priv = convert_any_priv_string(privtext, any_priv_map);

        result = (AclItem *) palloc(sizeof(AclItem));

        result->ai_grantee = grantee;
        result->ai_grantor = grantor;

        ACLITEM_SET_PRIVS_GOPTIONS(*result, priv,
                                                           (goption ? priv : ACL_NO_RIGHTS));

        PG_RETURN_ACLITEM_P(result);
}


/*
 * convert_any_priv_string: recognize privilege strings for has_foo_privilege
 *
 * We accept a comma-separated list of case-insensitive privilege names,
 * producing a bitmask of the OR'd privilege bits.  We are liberal about
 * whitespace between items, not so much about whitespace within items.
 * The allowed privilege names are given as an array of priv_map structs,
 * terminated by one with a NULL name pointer.
 */
static AclMode
convert_any_priv_string(text *priv_type_text,
                                                const priv_map *privileges)
{
        AclMode         result = 0;
        char       *priv_type = text_to_cstring(priv_type_text);
        char       *chunk;
        char       *next_chunk;

        /* We rely on priv_type being a private, modifiable string */
        for (chunk = priv_type; chunk; chunk = next_chunk)
        {
                int                     chunk_len;
                const priv_map *this_priv;

                /* Split string at commas */
                next_chunk = strchr(chunk, ',');
                if (next_chunk)
                        *next_chunk++ = '\0';

                /* Drop leading/trailing whitespace in this chunk */
                while (*chunk && isspace((unsigned char) *chunk))
                        chunk++;
                chunk_len = strlen(chunk);
                while (chunk_len > 0 && isspace((unsigned char) chunk[chunk_len - 1]))
                        chunk_len--;
                chunk[chunk_len] = '\0';

                /* Match to the privileges list */
                for (this_priv = privileges; this_priv->name; this_priv++)
                {
                        if (pg_strcasecmp(this_priv->name, chunk) == 0)
                        {
                                result |= this_priv->value;
                                break;
                        }
                }
                if (!this_priv->name)
                        ereport(ERROR,
                                        (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                                         errmsg("unrecognized privilege type: \"%s\"", chunk)));
        }

        pfree(priv_type);
        return result;
}


static const char *
convert_aclright_to_string(int aclright)
{
        switch (aclright)
        {
                case ACL_INSERT:
                        return "INSERT";
                case ACL_SELECT:
                        return "SELECT";
                case ACL_UPDATE:
                        return "UPDATE";
                case ACL_DELETE:
                        return "DELETE";
                case ACL_TRUNCATE:
                        return "TRUNCATE";
                case ACL_REFERENCES:
                        return "REFERENCES";
                case ACL_TRIGGER:
                        return "TRIGGER";
                case ACL_EXECUTE:
                        return "EXECUTE";
                case ACL_USAGE:
                        return "USAGE";
                case ACL_CREATE:
                        return "CREATE";
                case ACL_CREATE_TEMP:
                        return "TEMPORARY";
                case ACL_CONNECT:
                        return "CONNECT";
                case ACL_SET:
                        return "SET";
                case ACL_ALTER_SYSTEM:
                        return "ALTER SYSTEM";
                case ACL_MAINTAIN:
                        return "MAINTAIN";
                default:
                        elog(ERROR, "unrecognized aclright: %d", aclright);
                        return NULL;
        }
}


/*----------
 * Convert an aclitem[] to a table.
 *
 * Example:
 *
 * aclexplode('{=r/joe,foo=a*w/joe}'::aclitem[])
 *
 * returns the table
 *
 * {{ OID(joe), 0::OID,   'SELECT', false },
 *      { OID(joe), OID(foo), 'INSERT', true },
 *      { OID(joe), OID(foo), 'UPDATE', false }}
 *----------
 */
Datum
aclexplode(PG_FUNCTION_ARGS)
{
        Acl                *acl = PG_GETARG_ACL_P(0);
        FuncCallContext *funcctx;
        int                *idx;
        AclItem    *aidat;

        if (SRF_IS_FIRSTCALL())
        {
                TupleDesc       tupdesc;
                MemoryContext oldcontext;

                check_acl(acl);

                funcctx = SRF_FIRSTCALL_INIT();
                oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);

                /*
                 * build tupdesc for result tuples (matches out parameters in pg_proc
                 * entry)
                 */
                tupdesc = CreateTemplateTupleDesc(4);
                TupleDescInitEntry(tupdesc, (AttrNumber) 1, "grantor",
                                                   OIDOID, -1, 0);
                TupleDescInitEntry(tupdesc, (AttrNumber) 2, "grantee",
                                                   OIDOID, -1, 0);
                TupleDescInitEntry(tupdesc, (AttrNumber) 3, "privilege_type",
                                                   TEXTOID, -1, 0);
                TupleDescInitEntry(tupdesc, (AttrNumber) 4, "is_grantable",
                                                   BOOLOID, -1, 0);

                funcctx->tuple_desc = BlessTupleDesc(tupdesc);

                /* allocate memory for user context */
                idx = (int *) palloc(sizeof(int[2]));
                idx[0] = 0;                             /* ACL array item index */
                idx[1] = -1;                    /* privilege type counter */
                funcctx->user_fctx = idx;

                MemoryContextSwitchTo(oldcontext);
        }

        funcctx = SRF_PERCALL_SETUP();
        idx = (int *) funcctx->user_fctx;
        aidat = ACL_DAT(acl);

        /* need test here in case acl has no items */
        while (idx[0] < ACL_NUM(acl))
        {
                AclItem    *aidata;
                AclMode         priv_bit;

                idx[1]++;
                if (idx[1] == N_ACL_RIGHTS)
                {
                        idx[1] = 0;
                        idx[0]++;
                        if (idx[0] >= ACL_NUM(acl)) /* done */
                                break;
                }
                aidata = &aidat[idx[0]];
                priv_bit = UINT64CONST(1) << idx[1];

                if (ACLITEM_GET_PRIVS(*aidata) & priv_bit)
                {
                        Datum           result;
                        Datum           values[4];
                        bool            nulls[4] = {0};
                        HeapTuple       tuple;

                        values[0] = ObjectIdGetDatum(aidata->ai_grantor);
                        values[1] = ObjectIdGetDatum(aidata->ai_grantee);
                        values[2] = CStringGetTextDatum(convert_aclright_to_string(priv_bit));
                        values[3] = BoolGetDatum((ACLITEM_GET_GOPTIONS(*aidata) & priv_bit) != 0);

                        tuple = heap_form_tuple(funcctx->tuple_desc, values, nulls);
                        result = HeapTupleGetDatum(tuple);

                        SRF_RETURN_NEXT(funcctx, result);
                }
        }

        SRF_RETURN_DONE(funcctx);
}


/*
 * has_table_privilege variants
 *              These are all named "has_table_privilege" at the SQL level.
 *              They take various combinations of relation name, relation OID,
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not.  The variants that take a relation OID
 *              return NULL if the OID doesn't exist (rather than failing, as
 *              they did before Postgres 8.4).
 */

/*
 * has_table_privilege_name_name
 *              Check user privileges on a table given
 *              name username, text tablename, and text priv name.
 */
Datum
has_table_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            rolename = PG_GETARG_NAME(0);
        text       *tablename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     tableoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid_or_public(NameStr(*rolename));
        tableoid = convert_table_name(tablename);
        mode = convert_table_priv_string(priv_type_text);

        aclresult = pg_class_aclcheck(tableoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_table_privilege_name
 *              Check user privileges on a table given
 *              text tablename and text priv name.
 *              current_user is assumed
 */
Datum
has_table_privilege_name(PG_FUNCTION_ARGS)
{
        text       *tablename = PG_GETARG_TEXT_PP(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     tableoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        tableoid = convert_table_name(tablename);
        mode = convert_table_priv_string(priv_type_text);

        aclresult = pg_class_aclcheck(tableoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_table_privilege_name_id
 *              Check user privileges on a table given
 *              name usename, table oid, and text priv name.
 */
Datum
has_table_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     tableoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_table_priv_string(priv_type_text);

        aclresult = pg_class_aclcheck_ext(tableoid, roleid, mode, &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_table_privilege_id
 *              Check user privileges on a table given
 *              table oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_table_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     tableoid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = GetUserId();
        mode = convert_table_priv_string(priv_type_text);

        aclresult = pg_class_aclcheck_ext(tableoid, roleid, mode, &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_table_privilege_id_name
 *              Check user privileges on a table given
 *              roleid, text tablename, and text priv name.
 */
Datum
has_table_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *tablename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     tableoid;
        AclMode         mode;
        AclResult       aclresult;

        tableoid = convert_table_name(tablename);
        mode = convert_table_priv_string(priv_type_text);

        aclresult = pg_class_aclcheck(tableoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_table_privilege_id_id
 *              Check user privileges on a table given
 *              roleid, table oid, and text priv name.
 */
Datum
has_table_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     tableoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        mode = convert_table_priv_string(priv_type_text);

        aclresult = pg_class_aclcheck_ext(tableoid, roleid, mode, &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 *              Support routines for has_table_privilege family.
 */

/*
 * Given a table name expressed as a string, look it up and return Oid
 */
static Oid
convert_table_name(text *tablename)
{
        RangeVar   *relrv;

        relrv = makeRangeVarFromNameList(textToQualifiedNameList(tablename));

        /* We might not even have permissions on this relation; don't lock it. */
        return RangeVarGetRelid(relrv, NoLock, false);
}

/*
 * convert_table_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_table_priv_string(text *priv_type_text)
{
        static const priv_map table_priv_map[] = {
                {"SELECT", ACL_SELECT},
                {"SELECT WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_SELECT)},
                {"INSERT", ACL_INSERT},
                {"INSERT WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_INSERT)},
                {"UPDATE", ACL_UPDATE},
                {"UPDATE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_UPDATE)},
                {"DELETE", ACL_DELETE},
                {"DELETE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_DELETE)},
                {"TRUNCATE", ACL_TRUNCATE},
                {"TRUNCATE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_TRUNCATE)},
                {"REFERENCES", ACL_REFERENCES},
                {"REFERENCES WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_REFERENCES)},
                {"TRIGGER", ACL_TRIGGER},
                {"TRIGGER WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_TRIGGER)},
                {"MAINTAIN", ACL_MAINTAIN},
                {"MAINTAIN WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_MAINTAIN)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, table_priv_map);
}

/*
 * has_sequence_privilege variants
 *              These are all named "has_sequence_privilege" at the SQL level.
 *              They take various combinations of relation name, relation OID,
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not.  The variants that take a relation OID
 *              return NULL if the OID doesn't exist.
 */

/*
 * has_sequence_privilege_name_name
 *              Check user privileges on a sequence given
 *              name username, text sequencename, and text priv name.
 */
Datum
has_sequence_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            rolename = PG_GETARG_NAME(0);
        text       *sequencename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     sequenceoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid_or_public(NameStr(*rolename));
        mode = convert_sequence_priv_string(priv_type_text);
        sequenceoid = convert_table_name(sequencename);
        if (get_rel_relkind(sequenceoid) != RELKIND_SEQUENCE)
                ereport(ERROR,
                                (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                                 errmsg("\"%s\" is not a sequence",
                                                text_to_cstring(sequencename))));

        aclresult = pg_class_aclcheck(sequenceoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_sequence_privilege_name
 *              Check user privileges on a sequence given
 *              text sequencename and text priv name.
 *              current_user is assumed
 */
Datum
has_sequence_privilege_name(PG_FUNCTION_ARGS)
{
        text       *sequencename = PG_GETARG_TEXT_PP(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     sequenceoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        mode = convert_sequence_priv_string(priv_type_text);
        sequenceoid = convert_table_name(sequencename);
        if (get_rel_relkind(sequenceoid) != RELKIND_SEQUENCE)
                ereport(ERROR,
                                (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                                 errmsg("\"%s\" is not a sequence",
                                                text_to_cstring(sequencename))));

        aclresult = pg_class_aclcheck(sequenceoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_sequence_privilege_name_id
 *              Check user privileges on a sequence given
 *              name usename, sequence oid, and text priv name.
 */
Datum
has_sequence_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     sequenceoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        char            relkind;
        bool            is_missing = false;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_sequence_priv_string(priv_type_text);
        relkind = get_rel_relkind(sequenceoid);
        if (relkind == '\0')
                PG_RETURN_NULL();
        else if (relkind != RELKIND_SEQUENCE)
                ereport(ERROR,
                                (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                                 errmsg("\"%s\" is not a sequence",
                                                get_rel_name(sequenceoid))));

        aclresult = pg_class_aclcheck_ext(sequenceoid, roleid, mode, &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_sequence_privilege_id
 *              Check user privileges on a sequence given
 *              sequence oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_sequence_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     sequenceoid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        char            relkind;
        bool            is_missing = false;

        roleid = GetUserId();
        mode = convert_sequence_priv_string(priv_type_text);
        relkind = get_rel_relkind(sequenceoid);
        if (relkind == '\0')
                PG_RETURN_NULL();
        else if (relkind != RELKIND_SEQUENCE)
                ereport(ERROR,
                                (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                                 errmsg("\"%s\" is not a sequence",
                                                get_rel_name(sequenceoid))));

        aclresult = pg_class_aclcheck_ext(sequenceoid, roleid, mode, &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_sequence_privilege_id_name
 *              Check user privileges on a sequence given
 *              roleid, text sequencename, and text priv name.
 */
Datum
has_sequence_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *sequencename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     sequenceoid;
        AclMode         mode;
        AclResult       aclresult;

        mode = convert_sequence_priv_string(priv_type_text);
        sequenceoid = convert_table_name(sequencename);
        if (get_rel_relkind(sequenceoid) != RELKIND_SEQUENCE)
                ereport(ERROR,
                                (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                                 errmsg("\"%s\" is not a sequence",
                                                text_to_cstring(sequencename))));

        aclresult = pg_class_aclcheck(sequenceoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_sequence_privilege_id_id
 *              Check user privileges on a sequence given
 *              roleid, sequence oid, and text priv name.
 */
Datum
has_sequence_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     sequenceoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;
        char            relkind;
        bool            is_missing = false;

        mode = convert_sequence_priv_string(priv_type_text);
        relkind = get_rel_relkind(sequenceoid);
        if (relkind == '\0')
                PG_RETURN_NULL();
        else if (relkind != RELKIND_SEQUENCE)
                ereport(ERROR,
                                (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                                 errmsg("\"%s\" is not a sequence",
                                                get_rel_name(sequenceoid))));

        aclresult = pg_class_aclcheck_ext(sequenceoid, roleid, mode, &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * convert_sequence_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_sequence_priv_string(text *priv_type_text)
{
        static const priv_map sequence_priv_map[] = {
                {"USAGE", ACL_USAGE},
                {"USAGE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_USAGE)},
                {"SELECT", ACL_SELECT},
                {"SELECT WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_SELECT)},
                {"UPDATE", ACL_UPDATE},
                {"UPDATE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_UPDATE)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, sequence_priv_map);
}


/*
 * has_any_column_privilege variants
 *              These are all named "has_any_column_privilege" at the SQL level.
 *              They take various combinations of relation name, relation OID,
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege for any column of the table, false if not.  The variants
 *              that take a relation OID return NULL if the OID doesn't exist.
 */

/*
 * has_any_column_privilege_name_name
 *              Check user privileges on any column of a table given
 *              name username, text tablename, and text priv name.
 */
Datum
has_any_column_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            rolename = PG_GETARG_NAME(0);
        text       *tablename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     tableoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid_or_public(NameStr(*rolename));
        tableoid = convert_table_name(tablename);
        mode = convert_column_priv_string(priv_type_text);

        /* First check at table level, then examine each column if needed */
        aclresult = pg_class_aclcheck(tableoid, roleid, mode);
        if (aclresult != ACLCHECK_OK)
                aclresult = pg_attribute_aclcheck_all(tableoid, roleid, mode,
                                                                                          ACLMASK_ANY);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_any_column_privilege_name
 *              Check user privileges on any column of a table given
 *              text tablename and text priv name.
 *              current_user is assumed
 */
Datum
has_any_column_privilege_name(PG_FUNCTION_ARGS)
{
        text       *tablename = PG_GETARG_TEXT_PP(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     tableoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        tableoid = convert_table_name(tablename);
        mode = convert_column_priv_string(priv_type_text);

        /* First check at table level, then examine each column if needed */
        aclresult = pg_class_aclcheck(tableoid, roleid, mode);
        if (aclresult != ACLCHECK_OK)
                aclresult = pg_attribute_aclcheck_all(tableoid, roleid, mode,
                                                                                          ACLMASK_ANY);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_any_column_privilege_name_id
 *              Check user privileges on any column of a table given
 *              name usename, table oid, and text priv name.
 */
Datum
has_any_column_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     tableoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_column_priv_string(priv_type_text);

        /* First check at table level, then examine each column if needed */
        aclresult = pg_class_aclcheck_ext(tableoid, roleid, mode, &is_missing);
        if (aclresult != ACLCHECK_OK)
        {
                if (is_missing)
                        PG_RETURN_NULL();
                aclresult = pg_attribute_aclcheck_all_ext(tableoid, roleid, mode,
                                                                                                  ACLMASK_ANY, &is_missing);
                if (is_missing)
                        PG_RETURN_NULL();
        }

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_any_column_privilege_id
 *              Check user privileges on any column of a table given
 *              table oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_any_column_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     tableoid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = GetUserId();
        mode = convert_column_priv_string(priv_type_text);

        /* First check at table level, then examine each column if needed */
        aclresult = pg_class_aclcheck_ext(tableoid, roleid, mode, &is_missing);
        if (aclresult != ACLCHECK_OK)
        {
                if (is_missing)
                        PG_RETURN_NULL();
                aclresult = pg_attribute_aclcheck_all_ext(tableoid, roleid, mode,
                                                                                                  ACLMASK_ANY, &is_missing);
                if (is_missing)
                        PG_RETURN_NULL();
        }

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_any_column_privilege_id_name
 *              Check user privileges on any column of a table given
 *              roleid, text tablename, and text priv name.
 */
Datum
has_any_column_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *tablename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     tableoid;
        AclMode         mode;
        AclResult       aclresult;

        tableoid = convert_table_name(tablename);
        mode = convert_column_priv_string(priv_type_text);

        /* First check at table level, then examine each column if needed */
        aclresult = pg_class_aclcheck(tableoid, roleid, mode);
        if (aclresult != ACLCHECK_OK)
                aclresult = pg_attribute_aclcheck_all(tableoid, roleid, mode,
                                                                                          ACLMASK_ANY);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_any_column_privilege_id_id
 *              Check user privileges on any column of a table given
 *              roleid, table oid, and text priv name.
 */
Datum
has_any_column_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     tableoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        mode = convert_column_priv_string(priv_type_text);

        /* First check at table level, then examine each column if needed */
        aclresult = pg_class_aclcheck_ext(tableoid, roleid, mode, &is_missing);
        if (aclresult != ACLCHECK_OK)
        {
                if (is_missing)
                        PG_RETURN_NULL();
                aclresult = pg_attribute_aclcheck_all_ext(tableoid, roleid, mode,
                                                                                                  ACLMASK_ANY, &is_missing);
                if (is_missing)
                        PG_RETURN_NULL();
        }

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}


/*
 * has_column_privilege variants
 *              These are all named "has_column_privilege" at the SQL level.
 *              They take various combinations of relation name, relation OID,
 *              column name, column attnum, user name, user OID, or
 *              implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not.  The variants that take a relation OID
 *              return NULL (rather than throwing an error) if that relation OID
 *              doesn't exist.  Likewise, the variants that take an integer attnum
 *              return NULL (rather than throwing an error) if there is no such
 *              pg_attribute entry.  All variants return NULL if an attisdropped
 *              column is selected.  These rules are meant to avoid unnecessary
 *              failures in queries that scan pg_attribute.
 */

/*
 * column_privilege_check: check column privileges, but don't throw an error
 *              for dropped column or table
 *
 * Returns 1 if have the privilege, 0 if not, -1 if dropped column/table.
 */
static int
column_privilege_check(Oid tableoid, AttrNumber attnum,
                                           Oid roleid, AclMode mode)
{
        AclResult       aclresult;
        bool            is_missing = false;

        /*
         * If convert_column_name failed, we can just return -1 immediately.
         */
        if (attnum == InvalidAttrNumber)
                return -1;

        /*
         * Check for column-level privileges first. This serves in part as a check
         * on whether the column even exists, so we need to do it before checking
         * table-level privilege.
         */
        aclresult = pg_attribute_aclcheck_ext(tableoid, attnum, roleid,
                                                                                  mode, &is_missing);
        if (aclresult == ACLCHECK_OK)
                return 1;
        else if (is_missing)
                return -1;

        /* Next check if we have the privilege at the table level */
        aclresult = pg_class_aclcheck_ext(tableoid, roleid, mode, &is_missing);
        if (aclresult == ACLCHECK_OK)
                return 1;
        else if (is_missing)
                return -1;
        else
                return 0;
}

/*
 * has_column_privilege_name_name_name
 *              Check user privileges on a column given
 *              name username, text tablename, text colname, and text priv name.
 */
Datum
has_column_privilege_name_name_name(PG_FUNCTION_ARGS)
{
        Name            rolename = PG_GETARG_NAME(0);
        text       *tablename = PG_GETARG_TEXT_PP(1);
        text       *column = PG_GETARG_TEXT_PP(2);
        text       *priv_type_text = PG_GETARG_TEXT_PP(3);
        Oid                     roleid;
        Oid                     tableoid;
        AttrNumber      colattnum;
        AclMode         mode;
        int                     privresult;

        roleid = get_role_oid_or_public(NameStr(*rolename));
        tableoid = convert_table_name(tablename);
        colattnum = convert_column_name(tableoid, column);
        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 * has_column_privilege_name_name_attnum
 *              Check user privileges on a column given
 *              name username, text tablename, int attnum, and text priv name.
 */
Datum
has_column_privilege_name_name_attnum(PG_FUNCTION_ARGS)
{
        Name            rolename = PG_GETARG_NAME(0);
        text       *tablename = PG_GETARG_TEXT_PP(1);
        AttrNumber      colattnum = PG_GETARG_INT16(2);
        text       *priv_type_text = PG_GETARG_TEXT_PP(3);
        Oid                     roleid;
        Oid                     tableoid;
        AclMode         mode;
        int                     privresult;

        roleid = get_role_oid_or_public(NameStr(*rolename));
        tableoid = convert_table_name(tablename);
        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 * has_column_privilege_name_id_name
 *              Check user privileges on a column given
 *              name username, table oid, text colname, and text priv name.
 */
Datum
has_column_privilege_name_id_name(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     tableoid = PG_GETARG_OID(1);
        text       *column = PG_GETARG_TEXT_PP(2);
        text       *priv_type_text = PG_GETARG_TEXT_PP(3);
        Oid                     roleid;
        AttrNumber      colattnum;
        AclMode         mode;
        int                     privresult;

        roleid = get_role_oid_or_public(NameStr(*username));
        colattnum = convert_column_name(tableoid, column);
        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 * has_column_privilege_name_id_attnum
 *              Check user privileges on a column given
 *              name username, table oid, int attnum, and text priv name.
 */
Datum
has_column_privilege_name_id_attnum(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     tableoid = PG_GETARG_OID(1);
        AttrNumber      colattnum = PG_GETARG_INT16(2);
        text       *priv_type_text = PG_GETARG_TEXT_PP(3);
        Oid                     roleid;
        AclMode         mode;
        int                     privresult;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 * has_column_privilege_id_name_name
 *              Check user privileges on a column given
 *              oid roleid, text tablename, text colname, and text priv name.
 */
Datum
has_column_privilege_id_name_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *tablename = PG_GETARG_TEXT_PP(1);
        text       *column = PG_GETARG_TEXT_PP(2);
        text       *priv_type_text = PG_GETARG_TEXT_PP(3);
        Oid                     tableoid;
        AttrNumber      colattnum;
        AclMode         mode;
        int                     privresult;

        tableoid = convert_table_name(tablename);
        colattnum = convert_column_name(tableoid, column);
        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 * has_column_privilege_id_name_attnum
 *              Check user privileges on a column given
 *              oid roleid, text tablename, int attnum, and text priv name.
 */
Datum
has_column_privilege_id_name_attnum(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *tablename = PG_GETARG_TEXT_PP(1);
        AttrNumber      colattnum = PG_GETARG_INT16(2);
        text       *priv_type_text = PG_GETARG_TEXT_PP(3);
        Oid                     tableoid;
        AclMode         mode;
        int                     privresult;

        tableoid = convert_table_name(tablename);
        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 * has_column_privilege_id_id_name
 *              Check user privileges on a column given
 *              oid roleid, table oid, text colname, and text priv name.
 */
Datum
has_column_privilege_id_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     tableoid = PG_GETARG_OID(1);
        text       *column = PG_GETARG_TEXT_PP(2);
        text       *priv_type_text = PG_GETARG_TEXT_PP(3);
        AttrNumber      colattnum;
        AclMode         mode;
        int                     privresult;

        colattnum = convert_column_name(tableoid, column);
        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 * has_column_privilege_id_id_attnum
 *              Check user privileges on a column given
 *              oid roleid, table oid, int attnum, and text priv name.
 */
Datum
has_column_privilege_id_id_attnum(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     tableoid = PG_GETARG_OID(1);
        AttrNumber      colattnum = PG_GETARG_INT16(2);
        text       *priv_type_text = PG_GETARG_TEXT_PP(3);
        AclMode         mode;
        int                     privresult;

        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 * has_column_privilege_name_name
 *              Check user privileges on a column given
 *              text tablename, text colname, and text priv name.
 *              current_user is assumed
 */
Datum
has_column_privilege_name_name(PG_FUNCTION_ARGS)
{
        text       *tablename = PG_GETARG_TEXT_PP(0);
        text       *column = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     tableoid;
        AttrNumber      colattnum;
        AclMode         mode;
        int                     privresult;

        roleid = GetUserId();
        tableoid = convert_table_name(tablename);
        colattnum = convert_column_name(tableoid, column);
        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 * has_column_privilege_name_attnum
 *              Check user privileges on a column given
 *              text tablename, int attnum, and text priv name.
 *              current_user is assumed
 */
Datum
has_column_privilege_name_attnum(PG_FUNCTION_ARGS)
{
        text       *tablename = PG_GETARG_TEXT_PP(0);
        AttrNumber      colattnum = PG_GETARG_INT16(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     tableoid;
        AclMode         mode;
        int                     privresult;

        roleid = GetUserId();
        tableoid = convert_table_name(tablename);
        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 * has_column_privilege_id_name
 *              Check user privileges on a column given
 *              table oid, text colname, and text priv name.
 *              current_user is assumed
 */
Datum
has_column_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     tableoid = PG_GETARG_OID(0);
        text       *column = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AttrNumber      colattnum;
        AclMode         mode;
        int                     privresult;

        roleid = GetUserId();
        colattnum = convert_column_name(tableoid, column);
        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 * has_column_privilege_id_attnum
 *              Check user privileges on a column given
 *              table oid, int attnum, and text priv name.
 *              current_user is assumed
 */
Datum
has_column_privilege_id_attnum(PG_FUNCTION_ARGS)
{
        Oid                     tableoid = PG_GETARG_OID(0);
        AttrNumber      colattnum = PG_GETARG_INT16(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        int                     privresult;

        roleid = GetUserId();
        mode = convert_column_priv_string(priv_type_text);

        privresult = column_privilege_check(tableoid, colattnum, roleid, mode);
        if (privresult < 0)
                PG_RETURN_NULL();
        PG_RETURN_BOOL(privresult);
}

/*
 *              Support routines for has_column_privilege family.
 */

/*
 * Given a table OID and a column name expressed as a string, look it up
 * and return the column number.  Returns InvalidAttrNumber in cases
 * where caller should return NULL instead of failing.
 */
static AttrNumber
convert_column_name(Oid tableoid, text *column)
{
        char       *colname;
        HeapTuple       attTuple;
        AttrNumber      attnum;

        colname = text_to_cstring(column);

        /*
         * We don't use get_attnum() here because it will report that dropped
         * columns don't exist.  We need to treat dropped columns differently from
         * nonexistent columns.
         */
        attTuple = SearchSysCache2(ATTNAME,
                                                           ObjectIdGetDatum(tableoid),
                                                           CStringGetDatum(colname));
        if (HeapTupleIsValid(attTuple))
        {
                Form_pg_attribute attributeForm;

                attributeForm = (Form_pg_attribute) GETSTRUCT(attTuple);
                /* We want to return NULL for dropped columns */
                if (attributeForm->attisdropped)
                        attnum = InvalidAttrNumber;
                else
                        attnum = attributeForm->attnum;
                ReleaseSysCache(attTuple);
        }
        else
        {
                char       *tablename = get_rel_name(tableoid);

                /*
                 * If the table OID is bogus, or it's just been dropped, we'll get
                 * NULL back.  In such cases we want has_column_privilege to return
                 * NULL too, so just return InvalidAttrNumber.
                 */
                if (tablename != NULL)
                {
                        /* tableoid exists, colname does not, so throw error */
                        ereport(ERROR,
                                        (errcode(ERRCODE_UNDEFINED_COLUMN),
                                         errmsg("column \"%s\" of relation \"%s\" does not exist",
                                                        colname, tablename)));
                }
                /* tableoid doesn't exist, so act like attisdropped case */
                attnum = InvalidAttrNumber;
        }

        pfree(colname);
        return attnum;
}

/*
 * convert_column_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_column_priv_string(text *priv_type_text)
{
        static const priv_map column_priv_map[] = {
                {"SELECT", ACL_SELECT},
                {"SELECT WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_SELECT)},
                {"INSERT", ACL_INSERT},
                {"INSERT WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_INSERT)},
                {"UPDATE", ACL_UPDATE},
                {"UPDATE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_UPDATE)},
                {"REFERENCES", ACL_REFERENCES},
                {"REFERENCES WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_REFERENCES)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, column_priv_map);
}


/*
 * has_database_privilege variants
 *              These are all named "has_database_privilege" at the SQL level.
 *              They take various combinations of database name, database OID,
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not, or NULL if object doesn't exist.
 */

/*
 * has_database_privilege_name_name
 *              Check user privileges on a database given
 *              name username, text databasename, and text priv name.
 */
Datum
has_database_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        text       *databasename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     databaseoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid_or_public(NameStr(*username));
        databaseoid = convert_database_name(databasename);
        mode = convert_database_priv_string(priv_type_text);

        aclresult = object_aclcheck(DatabaseRelationId, databaseoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_database_privilege_name
 *              Check user privileges on a database given
 *              text databasename and text priv name.
 *              current_user is assumed
 */
Datum
has_database_privilege_name(PG_FUNCTION_ARGS)
{
        text       *databasename = PG_GETARG_TEXT_PP(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     databaseoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        databaseoid = convert_database_name(databasename);
        mode = convert_database_priv_string(priv_type_text);

        aclresult = object_aclcheck(DatabaseRelationId, databaseoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_database_privilege_name_id
 *              Check user privileges on a database given
 *              name usename, database oid, and text priv name.
 */
Datum
has_database_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     databaseoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_database_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(DatabaseRelationId, databaseoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_database_privilege_id
 *              Check user privileges on a database given
 *              database oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_database_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     databaseoid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = GetUserId();
        mode = convert_database_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(DatabaseRelationId, databaseoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_database_privilege_id_name
 *              Check user privileges on a database given
 *              roleid, text databasename, and text priv name.
 */
Datum
has_database_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *databasename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     databaseoid;
        AclMode         mode;
        AclResult       aclresult;

        databaseoid = convert_database_name(databasename);
        mode = convert_database_priv_string(priv_type_text);

        aclresult = object_aclcheck(DatabaseRelationId, databaseoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_database_privilege_id_id
 *              Check user privileges on a database given
 *              roleid, database oid, and text priv name.
 */
Datum
has_database_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     databaseoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        mode = convert_database_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(DatabaseRelationId, databaseoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 *              Support routines for has_database_privilege family.
 */

/*
 * Given a database name expressed as a string, look it up and return Oid
 */
static Oid
convert_database_name(text *databasename)
{
        char       *dbname = text_to_cstring(databasename);

        return get_database_oid(dbname, false);
}

/*
 * convert_database_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_database_priv_string(text *priv_type_text)
{
        static const priv_map database_priv_map[] = {
                {"CREATE", ACL_CREATE},
                {"CREATE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_CREATE)},
                {"TEMPORARY", ACL_CREATE_TEMP},
                {"TEMPORARY WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_CREATE_TEMP)},
                {"TEMP", ACL_CREATE_TEMP},
                {"TEMP WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_CREATE_TEMP)},
                {"CONNECT", ACL_CONNECT},
                {"CONNECT WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_CONNECT)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, database_priv_map);
}


/*
 * has_foreign_data_wrapper_privilege variants
 *              These are all named "has_foreign_data_wrapper_privilege" at the SQL level.
 *              They take various combinations of foreign-data wrapper name,
 *              fdw OID, user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not.
 */

/*
 * has_foreign_data_wrapper_privilege_name_name
 *              Check user privileges on a foreign-data wrapper given
 *              name username, text fdwname, and text priv name.
 */
Datum
has_foreign_data_wrapper_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        text       *fdwname = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     fdwid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid_or_public(NameStr(*username));
        fdwid = convert_foreign_data_wrapper_name(fdwname);
        mode = convert_foreign_data_wrapper_priv_string(priv_type_text);

        aclresult = object_aclcheck(ForeignDataWrapperRelationId, fdwid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_foreign_data_wrapper_privilege_name
 *              Check user privileges on a foreign-data wrapper given
 *              text fdwname and text priv name.
 *              current_user is assumed
 */
Datum
has_foreign_data_wrapper_privilege_name(PG_FUNCTION_ARGS)
{
        text       *fdwname = PG_GETARG_TEXT_PP(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     fdwid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        fdwid = convert_foreign_data_wrapper_name(fdwname);
        mode = convert_foreign_data_wrapper_priv_string(priv_type_text);

        aclresult = object_aclcheck(ForeignDataWrapperRelationId, fdwid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_foreign_data_wrapper_privilege_name_id
 *              Check user privileges on a foreign-data wrapper given
 *              name usename, foreign-data wrapper oid, and text priv name.
 */
Datum
has_foreign_data_wrapper_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     fdwid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_foreign_data_wrapper_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(ForeignDataWrapperRelationId, fdwid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_foreign_data_wrapper_privilege_id
 *              Check user privileges on a foreign-data wrapper given
 *              foreign-data wrapper oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_foreign_data_wrapper_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     fdwid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = GetUserId();
        mode = convert_foreign_data_wrapper_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(ForeignDataWrapperRelationId, fdwid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_foreign_data_wrapper_privilege_id_name
 *              Check user privileges on a foreign-data wrapper given
 *              roleid, text fdwname, and text priv name.
 */
Datum
has_foreign_data_wrapper_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *fdwname = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     fdwid;
        AclMode         mode;
        AclResult       aclresult;

        fdwid = convert_foreign_data_wrapper_name(fdwname);
        mode = convert_foreign_data_wrapper_priv_string(priv_type_text);

        aclresult = object_aclcheck(ForeignDataWrapperRelationId, fdwid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_foreign_data_wrapper_privilege_id_id
 *              Check user privileges on a foreign-data wrapper given
 *              roleid, fdw oid, and text priv name.
 */
Datum
has_foreign_data_wrapper_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     fdwid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        mode = convert_foreign_data_wrapper_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(ForeignDataWrapperRelationId, fdwid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 *              Support routines for has_foreign_data_wrapper_privilege family.
 */

/*
 * Given a FDW name expressed as a string, look it up and return Oid
 */
static Oid
convert_foreign_data_wrapper_name(text *fdwname)
{
        char       *fdwstr = text_to_cstring(fdwname);

        return get_foreign_data_wrapper_oid(fdwstr, false);
}

/*
 * convert_foreign_data_wrapper_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_foreign_data_wrapper_priv_string(text *priv_type_text)
{
        static const priv_map foreign_data_wrapper_priv_map[] = {
                {"USAGE", ACL_USAGE},
                {"USAGE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_USAGE)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, foreign_data_wrapper_priv_map);
}


/*
 * has_function_privilege variants
 *              These are all named "has_function_privilege" at the SQL level.
 *              They take various combinations of function name, function OID,
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not, or NULL if object doesn't exist.
 */

/*
 * has_function_privilege_name_name
 *              Check user privileges on a function given
 *              name username, text functionname, and text priv name.
 */
Datum
has_function_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        text       *functionname = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     functionoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid_or_public(NameStr(*username));
        functionoid = convert_function_name(functionname);
        mode = convert_function_priv_string(priv_type_text);

        aclresult = object_aclcheck(ProcedureRelationId, functionoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_function_privilege_name
 *              Check user privileges on a function given
 *              text functionname and text priv name.
 *              current_user is assumed
 */
Datum
has_function_privilege_name(PG_FUNCTION_ARGS)
{
        text       *functionname = PG_GETARG_TEXT_PP(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     functionoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        functionoid = convert_function_name(functionname);
        mode = convert_function_priv_string(priv_type_text);

        aclresult = object_aclcheck(ProcedureRelationId, functionoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_function_privilege_name_id
 *              Check user privileges on a function given
 *              name usename, function oid, and text priv name.
 */
Datum
has_function_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     functionoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_function_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(ProcedureRelationId, functionoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_function_privilege_id
 *              Check user privileges on a function given
 *              function oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_function_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     functionoid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = GetUserId();
        mode = convert_function_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(ProcedureRelationId, functionoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_function_privilege_id_name
 *              Check user privileges on a function given
 *              roleid, text functionname, and text priv name.
 */
Datum
has_function_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *functionname = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     functionoid;
        AclMode         mode;
        AclResult       aclresult;

        functionoid = convert_function_name(functionname);
        mode = convert_function_priv_string(priv_type_text);

        aclresult = object_aclcheck(ProcedureRelationId, functionoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_function_privilege_id_id
 *              Check user privileges on a function given
 *              roleid, function oid, and text priv name.
 */
Datum
has_function_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     functionoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        mode = convert_function_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(ProcedureRelationId, functionoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 *              Support routines for has_function_privilege family.
 */

/*
 * Given a function name expressed as a string, look it up and return Oid
 */
static Oid
convert_function_name(text *functionname)
{
        char       *funcname = text_to_cstring(functionname);
        Oid                     oid;

        oid = DatumGetObjectId(DirectFunctionCall1(regprocedurein,
                                                                                           CStringGetDatum(funcname)));

        if (!OidIsValid(oid))
                ereport(ERROR,
                                (errcode(ERRCODE_UNDEFINED_FUNCTION),
                                 errmsg("function \"%s\" does not exist", funcname)));

        return oid;
}

/*
 * convert_function_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_function_priv_string(text *priv_type_text)
{
        static const priv_map function_priv_map[] = {
                {"EXECUTE", ACL_EXECUTE},
                {"EXECUTE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_EXECUTE)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, function_priv_map);
}


/*
 * has_language_privilege variants
 *              These are all named "has_language_privilege" at the SQL level.
 *              They take various combinations of language name, language OID,
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not, or NULL if object doesn't exist.
 */

/*
 * has_language_privilege_name_name
 *              Check user privileges on a language given
 *              name username, text languagename, and text priv name.
 */
Datum
has_language_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        text       *languagename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     languageoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid_or_public(NameStr(*username));
        languageoid = convert_language_name(languagename);
        mode = convert_language_priv_string(priv_type_text);

        aclresult = object_aclcheck(LanguageRelationId, languageoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_language_privilege_name
 *              Check user privileges on a language given
 *              text languagename and text priv name.
 *              current_user is assumed
 */
Datum
has_language_privilege_name(PG_FUNCTION_ARGS)
{
        text       *languagename = PG_GETARG_TEXT_PP(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     languageoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        languageoid = convert_language_name(languagename);
        mode = convert_language_priv_string(priv_type_text);

        aclresult = object_aclcheck(LanguageRelationId, languageoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_language_privilege_name_id
 *              Check user privileges on a language given
 *              name usename, language oid, and text priv name.
 */
Datum
has_language_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     languageoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_language_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(LanguageRelationId, languageoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_language_privilege_id
 *              Check user privileges on a language given
 *              language oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_language_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     languageoid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = GetUserId();
        mode = convert_language_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(LanguageRelationId, languageoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_language_privilege_id_name
 *              Check user privileges on a language given
 *              roleid, text languagename, and text priv name.
 */
Datum
has_language_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *languagename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     languageoid;
        AclMode         mode;
        AclResult       aclresult;

        languageoid = convert_language_name(languagename);
        mode = convert_language_priv_string(priv_type_text);

        aclresult = object_aclcheck(LanguageRelationId, languageoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_language_privilege_id_id
 *              Check user privileges on a language given
 *              roleid, language oid, and text priv name.
 */
Datum
has_language_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     languageoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        mode = convert_language_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(LanguageRelationId, languageoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 *              Support routines for has_language_privilege family.
 */

/*
 * Given a language name expressed as a string, look it up and return Oid
 */
static Oid
convert_language_name(text *languagename)
{
        char       *langname = text_to_cstring(languagename);

        return get_language_oid(langname, false);
}

/*
 * convert_language_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_language_priv_string(text *priv_type_text)
{
        static const priv_map language_priv_map[] = {
                {"USAGE", ACL_USAGE},
                {"USAGE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_USAGE)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, language_priv_map);
}


/*
 * has_schema_privilege variants
 *              These are all named "has_schema_privilege" at the SQL level.
 *              They take various combinations of schema name, schema OID,
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not, or NULL if object doesn't exist.
 */

/*
 * has_schema_privilege_name_name
 *              Check user privileges on a schema given
 *              name username, text schemaname, and text priv name.
 */
Datum
has_schema_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        text       *schemaname = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     schemaoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid_or_public(NameStr(*username));
        schemaoid = convert_schema_name(schemaname);
        mode = convert_schema_priv_string(priv_type_text);

        aclresult = object_aclcheck(NamespaceRelationId, schemaoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_schema_privilege_name
 *              Check user privileges on a schema given
 *              text schemaname and text priv name.
 *              current_user is assumed
 */
Datum
has_schema_privilege_name(PG_FUNCTION_ARGS)
{
        text       *schemaname = PG_GETARG_TEXT_PP(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     schemaoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        schemaoid = convert_schema_name(schemaname);
        mode = convert_schema_priv_string(priv_type_text);

        aclresult = object_aclcheck(NamespaceRelationId, schemaoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_schema_privilege_name_id
 *              Check user privileges on a schema given
 *              name usename, schema oid, and text priv name.
 */
Datum
has_schema_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     schemaoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_schema_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(NamespaceRelationId, schemaoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_schema_privilege_id
 *              Check user privileges on a schema given
 *              schema oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_schema_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     schemaoid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = GetUserId();
        mode = convert_schema_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(NamespaceRelationId, schemaoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_schema_privilege_id_name
 *              Check user privileges on a schema given
 *              roleid, text schemaname, and text priv name.
 */
Datum
has_schema_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *schemaname = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     schemaoid;
        AclMode         mode;
        AclResult       aclresult;

        schemaoid = convert_schema_name(schemaname);
        mode = convert_schema_priv_string(priv_type_text);

        aclresult = object_aclcheck(NamespaceRelationId, schemaoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_schema_privilege_id_id
 *              Check user privileges on a schema given
 *              roleid, schema oid, and text priv name.
 */
Datum
has_schema_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     schemaoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        mode = convert_schema_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(NamespaceRelationId, schemaoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 *              Support routines for has_schema_privilege family.
 */

/*
 * Given a schema name expressed as a string, look it up and return Oid
 */
static Oid
convert_schema_name(text *schemaname)
{
        char       *nspname = text_to_cstring(schemaname);

        return get_namespace_oid(nspname, false);
}

/*
 * convert_schema_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_schema_priv_string(text *priv_type_text)
{
        static const priv_map schema_priv_map[] = {
                {"CREATE", ACL_CREATE},
                {"CREATE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_CREATE)},
                {"USAGE", ACL_USAGE},
                {"USAGE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_USAGE)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, schema_priv_map);
}


/*
 * has_server_privilege variants
 *              These are all named "has_server_privilege" at the SQL level.
 *              They take various combinations of foreign server name,
 *              server OID, user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not.
 */

/*
 * has_server_privilege_name_name
 *              Check user privileges on a foreign server given
 *              name username, text servername, and text priv name.
 */
Datum
has_server_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        text       *servername = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     serverid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid_or_public(NameStr(*username));
        serverid = convert_server_name(servername);
        mode = convert_server_priv_string(priv_type_text);

        aclresult = object_aclcheck(ForeignServerRelationId, serverid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_server_privilege_name
 *              Check user privileges on a foreign server given
 *              text servername and text priv name.
 *              current_user is assumed
 */
Datum
has_server_privilege_name(PG_FUNCTION_ARGS)
{
        text       *servername = PG_GETARG_TEXT_PP(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     serverid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        serverid = convert_server_name(servername);
        mode = convert_server_priv_string(priv_type_text);

        aclresult = object_aclcheck(ForeignServerRelationId, serverid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_server_privilege_name_id
 *              Check user privileges on a foreign server given
 *              name usename, foreign server oid, and text priv name.
 */
Datum
has_server_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     serverid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_server_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(ForeignServerRelationId, serverid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_server_privilege_id
 *              Check user privileges on a foreign server given
 *              server oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_server_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     serverid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = GetUserId();
        mode = convert_server_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(ForeignServerRelationId, serverid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_server_privilege_id_name
 *              Check user privileges on a foreign server given
 *              roleid, text servername, and text priv name.
 */
Datum
has_server_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *servername = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     serverid;
        AclMode         mode;
        AclResult       aclresult;

        serverid = convert_server_name(servername);
        mode = convert_server_priv_string(priv_type_text);

        aclresult = object_aclcheck(ForeignServerRelationId, serverid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_server_privilege_id_id
 *              Check user privileges on a foreign server given
 *              roleid, server oid, and text priv name.
 */
Datum
has_server_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     serverid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        mode = convert_server_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(ForeignServerRelationId, serverid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 *              Support routines for has_server_privilege family.
 */

/*
 * Given a server name expressed as a string, look it up and return Oid
 */
static Oid
convert_server_name(text *servername)
{
        char       *serverstr = text_to_cstring(servername);

        return get_foreign_server_oid(serverstr, false);
}

/*
 * convert_server_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_server_priv_string(text *priv_type_text)
{
        static const priv_map server_priv_map[] = {
                {"USAGE", ACL_USAGE},
                {"USAGE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_USAGE)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, server_priv_map);
}


/*
 * has_tablespace_privilege variants
 *              These are all named "has_tablespace_privilege" at the SQL level.
 *              They take various combinations of tablespace name, tablespace OID,
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not.
 */

/*
 * has_tablespace_privilege_name_name
 *              Check user privileges on a tablespace given
 *              name username, text tablespacename, and text priv name.
 */
Datum
has_tablespace_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        text       *tablespacename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     tablespaceoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid_or_public(NameStr(*username));
        tablespaceoid = convert_tablespace_name(tablespacename);
        mode = convert_tablespace_priv_string(priv_type_text);

        aclresult = object_aclcheck(TableSpaceRelationId, tablespaceoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_tablespace_privilege_name
 *              Check user privileges on a tablespace given
 *              text tablespacename and text priv name.
 *              current_user is assumed
 */
Datum
has_tablespace_privilege_name(PG_FUNCTION_ARGS)
{
        text       *tablespacename = PG_GETARG_TEXT_PP(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     tablespaceoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        tablespaceoid = convert_tablespace_name(tablespacename);
        mode = convert_tablespace_priv_string(priv_type_text);

        aclresult = object_aclcheck(TableSpaceRelationId, tablespaceoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_tablespace_privilege_name_id
 *              Check user privileges on a tablespace given
 *              name usename, tablespace oid, and text priv name.
 */
Datum
has_tablespace_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     tablespaceoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_tablespace_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(TableSpaceRelationId, tablespaceoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_tablespace_privilege_id
 *              Check user privileges on a tablespace given
 *              tablespace oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_tablespace_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     tablespaceoid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = GetUserId();
        mode = convert_tablespace_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(TableSpaceRelationId, tablespaceoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_tablespace_privilege_id_name
 *              Check user privileges on a tablespace given
 *              roleid, text tablespacename, and text priv name.
 */
Datum
has_tablespace_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *tablespacename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     tablespaceoid;
        AclMode         mode;
        AclResult       aclresult;

        tablespaceoid = convert_tablespace_name(tablespacename);
        mode = convert_tablespace_priv_string(priv_type_text);

        aclresult = object_aclcheck(TableSpaceRelationId, tablespaceoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_tablespace_privilege_id_id
 *              Check user privileges on a tablespace given
 *              roleid, tablespace oid, and text priv name.
 */
Datum
has_tablespace_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     tablespaceoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        mode = convert_tablespace_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(TableSpaceRelationId, tablespaceoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 *              Support routines for has_tablespace_privilege family.
 */

/*
 * Given a tablespace name expressed as a string, look it up and return Oid
 */
static Oid
convert_tablespace_name(text *tablespacename)
{
        char       *spcname = text_to_cstring(tablespacename);

        return get_tablespace_oid(spcname, false);
}

/*
 * convert_tablespace_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_tablespace_priv_string(text *priv_type_text)
{
        static const priv_map tablespace_priv_map[] = {
                {"CREATE", ACL_CREATE},
                {"CREATE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_CREATE)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, tablespace_priv_map);
}

/*
 * has_type_privilege variants
 *              These are all named "has_type_privilege" at the SQL level.
 *              They take various combinations of type name, type OID,
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not, or NULL if object doesn't exist.
 */

/*
 * has_type_privilege_name_name
 *              Check user privileges on a type given
 *              name username, text typename, and text priv name.
 */
Datum
has_type_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        text       *typename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     typeoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid_or_public(NameStr(*username));
        typeoid = convert_type_name(typename);
        mode = convert_type_priv_string(priv_type_text);

        aclresult = object_aclcheck(TypeRelationId, typeoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_type_privilege_name
 *              Check user privileges on a type given
 *              text typename and text priv name.
 *              current_user is assumed
 */
Datum
has_type_privilege_name(PG_FUNCTION_ARGS)
{
        text       *typename = PG_GETARG_TEXT_PP(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     typeoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        typeoid = convert_type_name(typename);
        mode = convert_type_priv_string(priv_type_text);

        aclresult = object_aclcheck(TypeRelationId, typeoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_type_privilege_name_id
 *              Check user privileges on a type given
 *              name usename, type oid, and text priv name.
 */
Datum
has_type_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     typeoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = get_role_oid_or_public(NameStr(*username));
        mode = convert_type_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(TypeRelationId, typeoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_type_privilege_id
 *              Check user privileges on a type given
 *              type oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_type_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     typeoid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        roleid = GetUserId();
        mode = convert_type_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(TypeRelationId, typeoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_type_privilege_id_name
 *              Check user privileges on a type given
 *              roleid, text typename, and text priv name.
 */
Datum
has_type_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *typename = PG_GETARG_TEXT_PP(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     typeoid;
        AclMode         mode;
        AclResult       aclresult;

        typeoid = convert_type_name(typename);
        mode = convert_type_priv_string(priv_type_text);

        aclresult = object_aclcheck(TypeRelationId, typeoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * has_type_privilege_id_id
 *              Check user privileges on a type given
 *              roleid, type oid, and text priv name.
 */
Datum
has_type_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     typeoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;
        bool            is_missing = false;

        mode = convert_type_priv_string(priv_type_text);

        aclresult = object_aclcheck_ext(TypeRelationId, typeoid,
                                                                        roleid, mode,
                                                                        &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 *              Support routines for has_type_privilege family.
 */

/*
 * Given a type name expressed as a string, look it up and return Oid
 */
static Oid
convert_type_name(text *typename)
{
        char       *typname = text_to_cstring(typename);
        Oid                     oid;

        oid = DatumGetObjectId(DirectFunctionCall1(regtypein,
                                                                                           CStringGetDatum(typname)));

        if (!OidIsValid(oid))
                ereport(ERROR,
                                (errcode(ERRCODE_UNDEFINED_OBJECT),
                                 errmsg("type \"%s\" does not exist", typname)));

        return oid;
}

/*
 * convert_type_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_type_priv_string(text *priv_type_text)
{
        static const priv_map type_priv_map[] = {
                {"USAGE", ACL_USAGE},
                {"USAGE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_USAGE)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, type_priv_map);
}

/*
 * has_parameter_privilege variants
 *              These are all named "has_parameter_privilege" at the SQL level.
 *              They take various combinations of parameter name with
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has been granted
 *              the indicated privilege or false if not.
 */

/*
 * has_param_priv_byname
 *
 *              Helper function to check user privileges on a parameter given the
 *              role by Oid, parameter by text name, and privileges as AclMode.
 */
static bool
has_param_priv_byname(Oid roleid, const text *parameter, AclMode priv)
{
        char       *paramstr = text_to_cstring(parameter);

        return pg_parameter_aclcheck(paramstr, roleid, priv) == ACLCHECK_OK;
}

/*
 * has_parameter_privilege_name_name
 *              Check user privileges on a parameter given name username, text
 *              parameter, and text priv name.
 */
Datum
has_parameter_privilege_name_name(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        text       *parameter = PG_GETARG_TEXT_PP(1);
        AclMode         priv = convert_parameter_priv_string(PG_GETARG_TEXT_PP(2));
        Oid                     roleid = get_role_oid_or_public(NameStr(*username));

        PG_RETURN_BOOL(has_param_priv_byname(roleid, parameter, priv));
}

/*
 * has_parameter_privilege_name
 *              Check user privileges on a parameter given text parameter and text priv
 *              name.  current_user is assumed
 */
Datum
has_parameter_privilege_name(PG_FUNCTION_ARGS)
{
        text       *parameter = PG_GETARG_TEXT_PP(0);
        AclMode         priv = convert_parameter_priv_string(PG_GETARG_TEXT_PP(1));

        PG_RETURN_BOOL(has_param_priv_byname(GetUserId(), parameter, priv));
}

/*
 * has_parameter_privilege_id_name
 *              Check user privileges on a parameter given roleid, text parameter, and
 *              text priv name.
 */
Datum
has_parameter_privilege_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        text       *parameter = PG_GETARG_TEXT_PP(1);
        AclMode         priv = convert_parameter_priv_string(PG_GETARG_TEXT_PP(2));

        PG_RETURN_BOOL(has_param_priv_byname(roleid, parameter, priv));
}

/*
 *              Support routines for has_parameter_privilege family.
 */

/*
 * convert_parameter_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_parameter_priv_string(text *priv_text)
{
        static const priv_map parameter_priv_map[] = {
                {"SET", ACL_SET},
                {"SET WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_SET)},
                {"ALTER SYSTEM", ACL_ALTER_SYSTEM},
                {"ALTER SYSTEM WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_ALTER_SYSTEM)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_text, parameter_priv_map);
}

/*
 * has_largeobject_privilege variants
 *              These are all named "has_largeobject_privilege" at the SQL level.
 *              They take various combinations of large object OID with
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not, or NULL if object doesn't exist.
 */

/*
 * has_lo_priv_byid
 *
 *              Helper function to check user privileges on a large object given the
 *              role by Oid, large object by Oid, and privileges as AclMode.
 */
static bool
has_lo_priv_byid(Oid roleid, Oid lobjId, AclMode priv, bool *is_missing)
{
        Snapshot        snapshot = NULL;
        AclResult       aclresult;

        if (priv & ACL_UPDATE)
                snapshot = NULL;
        else
                snapshot = GetActiveSnapshot();

        if (!LargeObjectExistsWithSnapshot(lobjId, snapshot))
        {
                Assert(is_missing != NULL);
                *is_missing = true;
                return false;
        }

        if (lo_compat_privileges)
                return true;

        aclresult = pg_largeobject_aclcheck_snapshot(lobjId,
                                                                                                 roleid,
                                                                                                 priv,
                                                                                                 snapshot);
        return aclresult == ACLCHECK_OK;
}

/*
 * has_largeobject_privilege_name_id
 *              Check user privileges on a large object given
 *              name username, large object oid, and text priv name.
 */
Datum
has_largeobject_privilege_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     roleid = get_role_oid_or_public(NameStr(*username));
        Oid                     lobjId = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        bool            is_missing = false;
        bool            result;

        mode = convert_largeobject_priv_string(priv_type_text);
        result = has_lo_priv_byid(roleid, lobjId, mode, &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(result);
}

/*
 * has_largeobject_privilege_id
 *              Check user privileges on a large object given
 *              large object oid, and text priv name.
 *              current_user is assumed
 */
Datum
has_largeobject_privilege_id(PG_FUNCTION_ARGS)
{
        Oid                     lobjId = PG_GETARG_OID(0);
        Oid                     roleid = GetUserId();
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        AclMode         mode;
        bool            is_missing = false;
        bool            result;

        mode = convert_largeobject_priv_string(priv_type_text);
        result = has_lo_priv_byid(roleid, lobjId, mode, &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(result);
}

/*
 * has_largeobject_privilege_id_id
 *              Check user privileges on a large object given
 *              roleid, large object oid, and text priv name.
 */
Datum
has_largeobject_privilege_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     lobjId = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        bool            is_missing = false;
        bool            result;

        mode = convert_largeobject_priv_string(priv_type_text);
        result = has_lo_priv_byid(roleid, lobjId, mode, &is_missing);

        if (is_missing)
                PG_RETURN_NULL();

        PG_RETURN_BOOL(result);
}

/*
 * convert_largeobject_priv_string
 *              Convert text string to AclMode value.
 */
static AclMode
convert_largeobject_priv_string(text *priv_type_text)
{
        static const priv_map largeobject_priv_map[] = {
                {"SELECT", ACL_SELECT},
                {"SELECT WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_SELECT)},
                {"UPDATE", ACL_UPDATE},
                {"UPDATE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_UPDATE)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, largeobject_priv_map);
}

/*
 * pg_has_role variants
 *              These are all named "pg_has_role" at the SQL level.
 *              They take various combinations of role name, role OID,
 *              user name, user OID, or implicit user = current_user.
 *
 *              The result is a boolean value: true if user has the indicated
 *              privilege, false if not.
 */

/*
 * pg_has_role_name_name
 *              Check user privileges on a role given
 *              name username, name rolename, and text priv name.
 */
Datum
pg_has_role_name_name(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Name            rolename = PG_GETARG_NAME(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        Oid                     roleoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid(NameStr(*username), false);
        roleoid = get_role_oid(NameStr(*rolename), false);
        mode = convert_role_priv_string(priv_type_text);

        aclresult = pg_role_aclcheck(roleoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * pg_has_role_name
 *              Check user privileges on a role given
 *              name rolename and text priv name.
 *              current_user is assumed
 */
Datum
pg_has_role_name(PG_FUNCTION_ARGS)
{
        Name            rolename = PG_GETARG_NAME(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        Oid                     roleoid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        roleoid = get_role_oid(NameStr(*rolename), false);
        mode = convert_role_priv_string(priv_type_text);

        aclresult = pg_role_aclcheck(roleoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * pg_has_role_name_id
 *              Check user privileges on a role given
 *              name usename, role oid, and text priv name.
 */
Datum
pg_has_role_name_id(PG_FUNCTION_ARGS)
{
        Name            username = PG_GETARG_NAME(0);
        Oid                     roleoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = get_role_oid(NameStr(*username), false);
        mode = convert_role_priv_string(priv_type_text);

        aclresult = pg_role_aclcheck(roleoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * pg_has_role_id
 *              Check user privileges on a role given
 *              role oid, and text priv name.
 *              current_user is assumed
 */
Datum
pg_has_role_id(PG_FUNCTION_ARGS)
{
        Oid                     roleoid = PG_GETARG_OID(0);
        text       *priv_type_text = PG_GETARG_TEXT_PP(1);
        Oid                     roleid;
        AclMode         mode;
        AclResult       aclresult;

        roleid = GetUserId();
        mode = convert_role_priv_string(priv_type_text);

        aclresult = pg_role_aclcheck(roleoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * pg_has_role_id_name
 *              Check user privileges on a role given
 *              roleid, name rolename, and text priv name.
 */
Datum
pg_has_role_id_name(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Name            rolename = PG_GETARG_NAME(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        Oid                     roleoid;
        AclMode         mode;
        AclResult       aclresult;

        roleoid = get_role_oid(NameStr(*rolename), false);
        mode = convert_role_priv_string(priv_type_text);

        aclresult = pg_role_aclcheck(roleoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 * pg_has_role_id_id
 *              Check user privileges on a role given
 *              roleid, role oid, and text priv name.
 */
Datum
pg_has_role_id_id(PG_FUNCTION_ARGS)
{
        Oid                     roleid = PG_GETARG_OID(0);
        Oid                     roleoid = PG_GETARG_OID(1);
        text       *priv_type_text = PG_GETARG_TEXT_PP(2);
        AclMode         mode;
        AclResult       aclresult;

        mode = convert_role_priv_string(priv_type_text);

        aclresult = pg_role_aclcheck(roleoid, roleid, mode);

        PG_RETURN_BOOL(aclresult == ACLCHECK_OK);
}

/*
 *              Support routines for pg_has_role family.
 */

/*
 * convert_role_priv_string
 *              Convert text string to AclMode value.
 *
 * We use USAGE to denote whether the privileges of the role are accessible
 * (has_privs_of_role), MEMBER to denote is_member, and MEMBER WITH GRANT
 * (or ADMIN) OPTION to denote is_admin.  There is no ACL bit corresponding
 * to MEMBER so we cheat and use ACL_CREATE for that.  This convention
 * is shared only with pg_role_aclcheck, below.
 */
static AclMode
convert_role_priv_string(text *priv_type_text)
{
        static const priv_map role_priv_map[] = {
                {"USAGE", ACL_USAGE},
                {"MEMBER", ACL_CREATE},
                {"SET", ACL_SET},
                {"USAGE WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_CREATE)},
                {"USAGE WITH ADMIN OPTION", ACL_GRANT_OPTION_FOR(ACL_CREATE)},
                {"MEMBER WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_CREATE)},
                {"MEMBER WITH ADMIN OPTION", ACL_GRANT_OPTION_FOR(ACL_CREATE)},
                {"SET WITH GRANT OPTION", ACL_GRANT_OPTION_FOR(ACL_CREATE)},
                {"SET WITH ADMIN OPTION", ACL_GRANT_OPTION_FOR(ACL_CREATE)},
                {NULL, 0}
        };

        return convert_any_priv_string(priv_type_text, role_priv_map);
}

/*
 * pg_role_aclcheck
 *              Quick-and-dirty support for pg_has_role
 */
static AclResult
pg_role_aclcheck(Oid role_oid, Oid roleid, AclMode mode)
{
        if (mode & ACL_GRANT_OPTION_FOR(ACL_CREATE))
        {
                if (is_admin_of_role(roleid, role_oid))
                        return ACLCHECK_OK;
        }
        if (mode & ACL_CREATE)
        {
                if (is_member_of_role(roleid, role_oid))
                        return ACLCHECK_OK;
        }
        if (mode & ACL_USAGE)
        {
                if (has_privs_of_role(roleid, role_oid))
                        return ACLCHECK_OK;
        }
        if (mode & ACL_SET)
        {
                if (member_can_set_role(roleid, role_oid))
                        return ACLCHECK_OK;
        }
        return ACLCHECK_NO_PRIV;
}


/*
 * initialization function (called by InitPostgres)
 */
void
initialize_acl(void)
{
        if (!IsBootstrapProcessingMode())
        {
                cached_db_hash =
                        GetSysCacheHashValue1(DATABASEOID,
                                                                  ObjectIdGetDatum(MyDatabaseId));

                /*
                 * In normal mode, set a callback on any syscache invalidation of rows
                 * of pg_auth_members (for roles_is_member_of()) pg_database (for
                 * roles_is_member_of())
                 */
                CacheRegisterSyscacheCallback(AUTHMEMROLEMEM,
                                                                          RoleMembershipCacheCallback,
                                                                          (Datum) 0);
                CacheRegisterSyscacheCallback(AUTHOID,
                                                                          RoleMembershipCacheCallback,
                                                                          (Datum) 0);
                CacheRegisterSyscacheCallback(DATABASEOID,
                                                                          RoleMembershipCacheCallback,
                                                                          (Datum) 0);
        }
}

/*
 * RoleMembershipCacheCallback
 *              Syscache inval callback function
 */
static void
RoleMembershipCacheCallback(Datum arg, int cacheid, uint32 hashvalue)
{
        if (cacheid == DATABASEOID &&
                hashvalue != cached_db_hash &&
                hashvalue != 0)
        {
                return;                                 /* ignore pg_database changes for other DBs */
        }

        /* Force membership caches to be recomputed on next use */
        cached_role[ROLERECURSE_MEMBERS] = InvalidOid;
        cached_role[ROLERECURSE_PRIVS] = InvalidOid;
        cached_role[ROLERECURSE_SETROLE] = InvalidOid;
}

/*
 * A helper function for roles_is_member_of() that provides an optimized
 * implementation of list_append_unique_oid() via a Bloom filter.  The caller
 * (i.e., roles_is_member_of()) is responsible for freeing bf once it is done
 * using this function.
 */
static inline List *
roles_list_append(List *roles_list, bloom_filter **bf, Oid role)
{
        unsigned char *roleptr = (unsigned char *) &role;

        /*
         * If there is a previously-created Bloom filter, use it to try to
         * determine whether the role is missing from the list.  If it says yes,
         * that's a hard fact and we can go ahead and add the role.  If it says
         * no, that's only probabilistic and we'd better search the list.  Without
         * a filter, we must always do an ordinary linear search through the
         * existing list.
         */
        if ((*bf && bloom_lacks_element(*bf, roleptr, sizeof(Oid))) ||
                !list_member_oid(roles_list, role))
        {
                /*
                 * If the list is large, we take on the overhead of creating and
                 * populating a Bloom filter to speed up future calls to this
                 * function.
                 */
                if (*bf == NULL &&
                        list_length(roles_list) > ROLES_LIST_BLOOM_THRESHOLD)
                {
                        *bf = bloom_create(ROLES_LIST_BLOOM_THRESHOLD * 10, work_mem, 0);
                        foreach_oid(roleid, roles_list)
                                bloom_add_element(*bf, (unsigned char *) &roleid, sizeof(Oid));
                }

                /*
                 * Finally, add the role to the list and the Bloom filter, if it
                 * exists.
                 */
                roles_list = lappend_oid(roles_list, role);
                if (*bf)
                        bloom_add_element(*bf, roleptr, sizeof(Oid));
        }

        return roles_list;
}

/*
 * Get a list of roles that the specified roleid is a member of
 *
 * Type ROLERECURSE_MEMBERS recurses through all grants; ROLERECURSE_PRIVS
 * recurses only through inheritable grants; and ROLERECURSE_SETROLE recurses
 * only through grants with set_option.
 *
 * Since indirect membership testing is relatively expensive, we cache
 * a list of memberships.  Hence, the result is only guaranteed good until
 * the next call of roles_is_member_of()!
 *
 * For the benefit of select_best_grantor, the result is defined to be
 * in breadth-first order, ie, closer relationships earlier.
 *
 * If admin_of is not InvalidOid, this function sets *admin_role, either
 * to the OID of the first role in the result list that directly possesses
 * ADMIN OPTION on the role corresponding to admin_of, or to InvalidOid if
 * there is no such role.
 */
static List *
roles_is_member_of(Oid roleid, enum RoleRecurseType type,
                                   Oid admin_of, Oid *admin_role)
{
        Oid                     dba;
        List       *roles_list;
        ListCell   *l;
        List       *new_cached_roles;
        MemoryContext oldctx;
        bloom_filter *bf = NULL;

        Assert(OidIsValid(admin_of) == PointerIsValid(admin_role));
        if (admin_role != NULL)
                *admin_role = InvalidOid;

        /* If cache is valid and ADMIN OPTION not sought, just return the list */
        if (cached_role[type] == roleid && !OidIsValid(admin_of) &&
                OidIsValid(cached_role[type]))
                return cached_roles[type];

        /*
         * Role expansion happens in a non-database backend when guc.c checks
         * ROLE_PG_READ_ALL_SETTINGS for a physical walsender SHOW command.  In
         * that case, no role gets pg_database_owner.
         */
        if (!OidIsValid(MyDatabaseId))
                dba = InvalidOid;
        else
        {
                HeapTuple       dbtup;

                dbtup = SearchSysCache1(DATABASEOID, ObjectIdGetDatum(MyDatabaseId));
                if (!HeapTupleIsValid(dbtup))
                        elog(ERROR, "cache lookup failed for database %u", MyDatabaseId);
                dba = ((Form_pg_database) GETSTRUCT(dbtup))->datdba;
                ReleaseSysCache(dbtup);
        }

        /*
         * Find all the roles that roleid is a member of, including multi-level
         * recursion.  The role itself will always be the first element of the
         * resulting list.
         *
         * Each element of the list is scanned to see if it adds any indirect
         * memberships.  We can use a single list as both the record of
         * already-found memberships and the agenda of roles yet to be scanned.
         * This is a bit tricky but works because the foreach() macro doesn't
         * fetch the next list element until the bottom of the loop.
         */
        roles_list = list_make1_oid(roleid);

        foreach(l, roles_list)
        {
                Oid                     memberid = lfirst_oid(l);
                CatCList   *memlist;
                int                     i;

                /* Find roles that memberid is directly a member of */
                memlist = SearchSysCacheList1(AUTHMEMMEMROLE,
                                                                          ObjectIdGetDatum(memberid));
                for (i = 0; i < memlist->n_members; i++)
                {
                        HeapTuple       tup = &memlist->members[i]->tuple;
                        Form_pg_auth_members form = (Form_pg_auth_members) GETSTRUCT(tup);
                        Oid                     otherid = form->roleid;

                        /*
                         * While otherid==InvalidOid shouldn't appear in the catalog, the
                         * OidIsValid() avoids crashing if that arises.
                         */
                        if (otherid == admin_of && form->admin_option &&
                                OidIsValid(admin_of) && !OidIsValid(*admin_role))
                                *admin_role = memberid;

                        /* If we're supposed to ignore non-heritable grants, do so. */
                        if (type == ROLERECURSE_PRIVS && !form->inherit_option)
                                continue;

                        /* If we're supposed to ignore non-SET grants, do so. */
                        if (type == ROLERECURSE_SETROLE && !form->set_option)
                                continue;

                        /*
                         * Even though there shouldn't be any loops in the membership
                         * graph, we must test for having already seen this role. It is
                         * legal for instance to have both A->B and A->C->B.
                         */
                        roles_list = roles_list_append(roles_list, &bf, otherid);
                }
                ReleaseSysCacheList(memlist);

                /* implement pg_database_owner implicit membership */
                if (memberid == dba && OidIsValid(dba))
                        roles_list = roles_list_append(roles_list, &bf,
                                                                                   ROLE_PG_DATABASE_OWNER);
        }

        /*
         * Free the Bloom filter created by roles_list_append(), if there is one.
         */
        if (bf)
                bloom_free(bf);

        /*
         * Copy the completed list into TopMemoryContext so it will persist.
         */
        oldctx = MemoryContextSwitchTo(TopMemoryContext);
        new_cached_roles = list_copy(roles_list);
        MemoryContextSwitchTo(oldctx);
        list_free(roles_list);

        /*
         * Now safe to assign to state variable
         */
        cached_role[type] = InvalidOid; /* just paranoia */
        list_free(cached_roles[type]);
        cached_roles[type] = new_cached_roles;
        cached_role[type] = roleid;

        /* And now we can return the answer */
        return cached_roles[type];
}


/*
 * Does member have the privileges of role (directly or indirectly)?
 *
 * This is defined not to recurse through grants that are not inherited,
 * and only inherited grants confer the associated privileges automatically.
 *
 * See also member_can_set_role, below.
 */
bool
has_privs_of_role(Oid member, Oid role)
{
        /* Fast path for simple case */
        if (member == role)
                return true;

        /* Superusers have every privilege, so are part of every role */
        if (superuser_arg(member))
                return true;

        /*
         * Find all the roles that member has the privileges of, including
         * multi-level recursion, then see if target role is any one of them.
         */
        return list_member_oid(roles_is_member_of(member, ROLERECURSE_PRIVS,
                                                                                          InvalidOid, NULL),
                                                   role);
}

/*
 * Can member use SET ROLE to this role?
 *
 * There must be a chain of grants from 'member' to 'role' each of which
 * permits SET ROLE; that is, each of which has set_option = true.
 *
 * It doesn't matter whether the grants are inheritable. That's a separate
 * question; see has_privs_of_role.
 *
 * This function should be used to determine whether the session user can
 * use SET ROLE to become the target user. We also use it to determine whether
 * the session user can change an existing object to be owned by the target
 * user, or create new objects owned by the target user.
 */
bool
member_can_set_role(Oid member, Oid role)
{
        /* Fast path for simple case */
        if (member == role)
                return true;

        /* Superusers have every privilege, so can always SET ROLE */
        if (superuser_arg(member))
                return true;

        /*
         * Find all the roles that member can access via SET ROLE, including
         * multi-level recursion, then see if target role is any one of them.
         */
        return list_member_oid(roles_is_member_of(member, ROLERECURSE_SETROLE,
                                                                                          InvalidOid, NULL),
                                                   role);
}

/*
 * Permission violation error unless able to SET ROLE to target role.
 */
void
check_can_set_role(Oid member, Oid role)
{
        if (!member_can_set_role(member, role))
                ereport(ERROR,
                                (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                                 errmsg("must be able to SET ROLE \"%s\"",
                                                GetUserNameFromId(role, false))));
}

/*
 * Is member a member of role (directly or indirectly)?
 *
 * This is defined to recurse through grants whether they are inherited or not.
 *
 * Do not use this for privilege checking, instead use has_privs_of_role().
 * Don't use it for determining whether it's possible to SET ROLE to some
 * other role; for that, use member_can_set_role(). And don't use it for
 * determining whether it's OK to create an object owned by some other role:
 * use member_can_set_role() for that, too.
 *
 * In short, calling this function is the wrong thing to do nearly everywhere.
 */
bool
is_member_of_role(Oid member, Oid role)
{
        /* Fast path for simple case */
        if (member == role)
                return true;

        /* Superusers have every privilege, so are part of every role */
        if (superuser_arg(member))
                return true;

        /*
         * Find all the roles that member is a member of, including multi-level
         * recursion, then see if target role is any one of them.
         */
        return list_member_oid(roles_is_member_of(member, ROLERECURSE_MEMBERS,
                                                                                          InvalidOid, NULL),
                                                   role);
}

/*
 * Is member a member of role, not considering superuserness?
 *
 * This is identical to is_member_of_role except we ignore superuser
 * status.
 *
 * Do not use this for privilege checking, instead use has_privs_of_role()
 */
bool
is_member_of_role_nosuper(Oid member, Oid role)
{
        /* Fast path for simple case */
        if (member == role)
                return true;

        /*
         * Find all the roles that member is a member of, including multi-level
         * recursion, then see if target role is any one of them.
         */
        return list_member_oid(roles_is_member_of(member, ROLERECURSE_MEMBERS,
                                                                                          InvalidOid, NULL),
                                                   role);
}


/*
 * Is member an admin of role?  That is, is member the role itself (subject to
 * restrictions below), a member (directly or indirectly) WITH ADMIN OPTION,
 * or a superuser?
 */
bool
is_admin_of_role(Oid member, Oid role)
{
        Oid                     admin_role;

        if (superuser_arg(member))
                return true;

        /* By policy, a role cannot have WITH ADMIN OPTION on itself. */
        if (member == role)
                return false;

        (void) roles_is_member_of(member, ROLERECURSE_MEMBERS, role, &admin_role);
        return OidIsValid(admin_role);
}

/*
 * Find a role whose privileges "member" inherits which has ADMIN OPTION
 * on "role", ignoring super-userness.
 *
 * There might be more than one such role; prefer one which involves fewer
 * hops. That is, if member has ADMIN OPTION, prefer that over all other
 * options; if not, prefer a role from which member inherits more directly
 * over more indirect inheritance.
 */
Oid
select_best_admin(Oid member, Oid role)
{
        Oid                     admin_role;

        /* By policy, a role cannot have WITH ADMIN OPTION on itself. */
        if (member == role)
                return InvalidOid;

        (void) roles_is_member_of(member, ROLERECURSE_PRIVS, role, &admin_role);
        return admin_role;
}


/* does what it says ... */
static int
count_one_bits(AclMode mask)
{
        int                     nbits = 0;

        /* this code relies on AclMode being an unsigned type */
        while (mask)
        {
                if (mask & 1)
                        nbits++;
                mask >>= 1;
        }
        return nbits;
}


/*
 * Select the effective grantor ID for a GRANT or REVOKE operation.
 *
 * The grantor must always be either the object owner or some role that has
 * been explicitly granted grant options.  This ensures that all granted
 * privileges appear to flow from the object owner, and there are never
 * multiple "original sources" of a privilege.  Therefore, if the would-be
 * grantor is a member of a role that has the needed grant options, we have
 * to do the grant as that role instead.
 *
 * It is possible that the would-be grantor is a member of several roles
 * that have different subsets of the desired grant options, but no one
 * role has 'em all.  In this case we pick a role with the largest number
 * of desired options.  Ties are broken in favor of closer ancestors.
 *
 * roleId: the role attempting to do the GRANT/REVOKE
 * privileges: the privileges to be granted/revoked
 * acl: the ACL of the object in question
 * ownerId: the role owning the object in question
 * *grantorId: receives the OID of the role to do the grant as
 * *grantOptions: receives the grant options actually held by grantorId
 *
 * If no grant options exist, we set grantorId to roleId, grantOptions to 0.
 */
void
select_best_grantor(Oid roleId, AclMode privileges,
                                        const Acl *acl, Oid ownerId,
                                        Oid *grantorId, AclMode *grantOptions)
{
        AclMode         needed_goptions = ACL_GRANT_OPTION_FOR(privileges);
        List       *roles_list;
        int                     nrights;
        ListCell   *l;

        /*
         * The object owner is always treated as having all grant options, so if
         * roleId is the owner it's easy.  Also, if roleId is a superuser it's
         * easy: superusers are implicitly members of every role, so they act as
         * the object owner.
         */
        if (roleId == ownerId || superuser_arg(roleId))
        {
                *grantorId = ownerId;
                *grantOptions = needed_goptions;
                return;
        }

        /*
         * Otherwise we have to do a careful search to see if roleId has the
         * privileges of any suitable role.  Note: we can hang onto the result of
         * roles_is_member_of() throughout this loop, because aclmask_direct()
         * doesn't query any role memberships.
         */
        roles_list = roles_is_member_of(roleId, ROLERECURSE_PRIVS,
                                                                        InvalidOid, NULL);

        /* initialize candidate result as default */
        *grantorId = roleId;
        *grantOptions = ACL_NO_RIGHTS;
        nrights = 0;

        foreach(l, roles_list)
        {
                Oid                     otherrole = lfirst_oid(l);
                AclMode         otherprivs;

                otherprivs = aclmask_direct(acl, otherrole, ownerId,
                                                                        needed_goptions, ACLMASK_ALL);
                if (otherprivs == needed_goptions)
                {
                        /* Found a suitable grantor */
                        *grantorId = otherrole;
                        *grantOptions = otherprivs;
                        return;
                }

                /*
                 * If it has just some of the needed privileges, remember best
                 * candidate.
                 */
                if (otherprivs != ACL_NO_RIGHTS)
                {
                        int                     nnewrights = count_one_bits(otherprivs);

                        if (nnewrights > nrights)
                        {
                                *grantorId = otherrole;
                                *grantOptions = otherprivs;
                                nrights = nnewrights;
                        }
                }
        }
}

/*
 * get_role_oid - Given a role name, look up the role's OID.
 *
 * If missing_ok is false, throw an error if role name not found.  If
 * true, just return InvalidOid.
 */
Oid
get_role_oid(const char *rolname, bool missing_ok)
{
        Oid                     oid;

        oid = GetSysCacheOid1(AUTHNAME, Anum_pg_authid_oid,
                                                  CStringGetDatum(rolname));
        if (!OidIsValid(oid) && !missing_ok)
                ereport(ERROR,
                                (errcode(ERRCODE_UNDEFINED_OBJECT),
                                 errmsg("role \"%s\" does not exist", rolname)));
        return oid;
}

/*
 * get_role_oid_or_public - As above, but return ACL_ID_PUBLIC if the
 *              role name is "public".
 */
Oid
get_role_oid_or_public(const char *rolname)
{
        if (strcmp(rolname, "public") == 0)
                return ACL_ID_PUBLIC;

        return get_role_oid(rolname, false);
}

/*
 * Given a RoleSpec node, return the OID it corresponds to.  If missing_ok is
 * true, return InvalidOid if the role does not exist.
 *
 * PUBLIC is always disallowed here.  Routines wanting to handle the PUBLIC
 * case must check the case separately.
 */
Oid
get_rolespec_oid(const RoleSpec *role, bool missing_ok)
{
        Oid                     oid;

        switch (role->roletype)
        {
                case ROLESPEC_CSTRING:
                        Assert(role->rolename);
                        oid = get_role_oid(role->rolename, missing_ok);
                        break;

                case ROLESPEC_CURRENT_ROLE:
                case ROLESPEC_CURRENT_USER:
                        oid = GetUserId();
                        break;

                case ROLESPEC_SESSION_USER:
                        oid = GetSessionUserId();
                        break;

                case ROLESPEC_PUBLIC:
                        ereport(ERROR,
                                        (errcode(ERRCODE_UNDEFINED_OBJECT),
                                         errmsg("role \"%s\" does not exist", "public")));
                        oid = InvalidOid;       /* make compiler happy */
                        break;

                default:
                        elog(ERROR, "unexpected role type %d", role->roletype);
        }

        return oid;
}

/*
 * Given a RoleSpec node, return the pg_authid HeapTuple it corresponds to.
 * Caller must ReleaseSysCache when done with the result tuple.
 */
HeapTuple
get_rolespec_tuple(const RoleSpec *role)
{
        HeapTuple       tuple;

        switch (role->roletype)
        {
                case ROLESPEC_CSTRING:
                        Assert(role->rolename);
                        tuple = SearchSysCache1(AUTHNAME, CStringGetDatum(role->rolename));
                        if (!HeapTupleIsValid(tuple))
                                ereport(ERROR,
                                                (errcode(ERRCODE_UNDEFINED_OBJECT),
                                                 errmsg("role \"%s\" does not exist", role->rolename)));
                        break;

                case ROLESPEC_CURRENT_ROLE:
                case ROLESPEC_CURRENT_USER:
                        tuple = SearchSysCache1(AUTHOID, ObjectIdGetDatum(GetUserId()));
                        if (!HeapTupleIsValid(tuple))
                                elog(ERROR, "cache lookup failed for role %u", GetUserId());
                        break;

                case ROLESPEC_SESSION_USER:
                        tuple = SearchSysCache1(AUTHOID, ObjectIdGetDatum(GetSessionUserId()));
                        if (!HeapTupleIsValid(tuple))
                                elog(ERROR, "cache lookup failed for role %u", GetSessionUserId());
                        break;

                case ROLESPEC_PUBLIC:
                        ereport(ERROR,
                                        (errcode(ERRCODE_UNDEFINED_OBJECT),
                                         errmsg("role \"%s\" does not exist", "public")));
                        tuple = NULL;           /* make compiler happy */
                        break;

                default:
                        elog(ERROR, "unexpected role type %d", role->roletype);
        }

        return tuple;
}

/*
 * Given a RoleSpec, returns a palloc'ed copy of the corresponding role's name.
 */
char *
get_rolespec_name(const RoleSpec *role)
{
        HeapTuple       tp;
        Form_pg_authid authForm;
        char       *rolename;

        tp = get_rolespec_tuple(role);
        authForm = (Form_pg_authid) GETSTRUCT(tp);
        rolename = pstrdup(NameStr(authForm->rolname));
        ReleaseSysCache(tp);

        return rolename;
}

/*
 * Given a RoleSpec, throw an error if the name is reserved, using detail_msg,
 * if provided (which must be already translated).
 *
 * If node is NULL, no error is thrown.  If detail_msg is NULL then no detail
 * message is provided.
 */
void
check_rolespec_name(const RoleSpec *role, const char *detail_msg)
{
        if (!role)
                return;

        if (role->roletype != ROLESPEC_CSTRING)
                return;

        if (IsReservedName(role->rolename))
        {
                if (detail_msg)
                        ereport(ERROR,
                                        (errcode(ERRCODE_RESERVED_NAME),
                                         errmsg("role name \"%s\" is reserved",
                                                        role->rolename),
                                         errdetail_internal("%s", detail_msg)));
                else
                        ereport(ERROR,
                                        (errcode(ERRCODE_RESERVED_NAME),
                                         errmsg("role name \"%s\" is reserved",
                                                        role->rolename)));
        }
}