YugabyteDB (2.13.0.0-b42, bfc6a6643e7399ac8a0e81d06a3ee6d6571b33ab)

/*-------------------------------------------------------------------------

 *

 * hashvalidate.c

 *    Opclass validator for hash.

 *

 * Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group

 * Portions Copyright (c) 1994, Regents of the University of California

 *

 * IDENTIFICATION

 *    src/backend/access/hash/hashvalidate.c

 *

 *-------------------------------------------------------------------------

 */

#include "postgres.h"

#include "access/amvalidate.h"

#include "access/hash.h"

#include "access/htup_details.h"

#include "catalog/pg_amop.h"

#include "catalog/pg_amproc.h"

#include "catalog/pg_opclass.h"

#include "catalog/pg_opfamily.h"

#include "catalog/pg_proc.h"

#include "catalog/pg_type.h"

#include "parser/parse_coerce.h"

#include "utils/builtins.h"

#include "utils/fmgroids.h"

#include "utils/regproc.h"

#include "utils/syscache.h"

static bool check_hash_func_signature(Oid funcid, int16 amprocnum, Oid argtype);

/*

 * Validator for a hash opclass.

 *

 * Some of the checks done here cover the whole opfamily, and therefore are

 * redundant when checking each opclass in a family.  But they don't run long

 * enough to be much of a problem, so we accept the duplication rather than

 * complicate the amvalidate API.

 */

bool

hashvalidate(Oid opclassoid)

{

  bool    result = true;

  HeapTuple classtup;

  Form_pg_opclass classform;

  Oid     opfamilyoid;

  Oid     opcintype;

  char     *opclassname;

  HeapTuple familytup;

  Form_pg_opfamily familyform;

  char     *opfamilyname;

  CatCList   *proclist,

         *oprlist;

  List     *grouplist;

  OpFamilyOpFuncGroup *opclassgroup;

  List     *hashabletypes = NIL;

  int     i;

  ListCell   *lc;

  /* Fetch opclass information */

  classtup = SearchSysCache1(CLAOID, ObjectIdGetDatum(opclassoid));

  if (!HeapTupleIsValid(classtup))

    elog(ERROR, "cache lookup failed for operator class %u", opclassoid);

  classform = (Form_pg_opclass) GETSTRUCT(classtup);

  opfamilyoid = classform->opcfamily;

  opcintype = classform->opcintype;

  opclassname = NameStr(classform->opcname);

  /* Fetch opfamily information */

  familytup = SearchSysCache1(OPFAMILYOID, ObjectIdGetDatum(opfamilyoid));

  if (!HeapTupleIsValid(familytup))

    elog(ERROR, "cache lookup failed for operator family %u", opfamilyoid);

  familyform = (Form_pg_opfamily) GETSTRUCT(familytup);

  opfamilyname = NameStr(familyform->opfname);

  /* Fetch all operators and support functions of the opfamily */

  oprlist = SearchSysCacheList1(AMOPSTRATEGY, ObjectIdGetDatum(opfamilyoid));

  proclist = SearchSysCacheList1(AMPROCNUM, ObjectIdGetDatum(opfamilyoid));

  /* Check individual support functions */

  for (i = 0; i < proclist->n_members; i++)

  {

    HeapTuple proctup = &proclist->members[i]->tuple;

    Form_pg_amproc procform = (Form_pg_amproc) GETSTRUCT(proctup);

    /*

     * All hash functions should be registered with matching left/right

     * types

     */

    if (procform->amproclefttype != procform->amprocrighttype)

    {

      ereport(INFO,

          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),

           errmsg("operator family \"%s\" of access method %s contains support function %s with different left and right input types",

              opfamilyname, "hash",

              format_procedure(procform->amproc))));

      result = false;

    }

    /* Check procedure numbers and function signatures */

    switch (procform->amprocnum)

    {

      case HASHSTANDARD_PROC:

      case HASHEXTENDED_PROC:

        if (!check_hash_func_signature(procform->amproc, procform->amprocnum,

                         procform->amproclefttype))

        {

          ereport(INFO,

              (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),

               errmsg("operator family \"%s\" of access method %s contains function %s with wrong signature for support number %d",

                  opfamilyname, "hash",

                  format_procedure(procform->amproc),

                  procform->amprocnum)));

          result = false;

        }

        else

        {

          /* Remember which types we can hash */

          hashabletypes =

            list_append_unique_oid(hashabletypes,

                         procform->amproclefttype);

        }

        break;

      default:

        ereport(INFO,

            (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),

             errmsg("operator family \"%s\" of access method %s contains function %s with invalid support number %d",

                opfamilyname, "hash",

                format_procedure(procform->amproc),

                procform->amprocnum)));

        result = false;

        break;

    }

  }

  /* Check individual operators */

  for (i = 0; i < oprlist->n_members; i++)

  {

    HeapTuple oprtup = &oprlist->members[i]->tuple;

    Form_pg_amop oprform = (Form_pg_amop) GETSTRUCT(oprtup);

    /* Check that only allowed strategy numbers exist */

    if (oprform->amopstrategy < 1 ||

      oprform->amopstrategy > HTMaxStrategyNumber)

    {

      ereport(INFO,

          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),

           errmsg("operator family \"%s\" of access method %s contains operator %s with invalid strategy number %d",

              opfamilyname, "hash",

              format_operator(oprform->amopopr),

              oprform->amopstrategy)));

      result = false;

    }

    /* hash doesn't support ORDER BY operators */

    if (oprform->amoppurpose != AMOP_SEARCH ||

      OidIsValid(oprform->amopsortfamily))

    {

      ereport(INFO,

          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),

           errmsg("operator family \"%s\" of access method %s contains invalid ORDER BY specification for operator %s",

              opfamilyname, "hash",

              format_operator(oprform->amopopr))));

      result = false;

    }

    /* Check operator signature --- same for all hash strategies */

    if (!check_amop_signature(oprform->amopopr, BOOLOID,

                  oprform->amoplefttype,

                  oprform->amoprighttype))

    {

      ereport(INFO,

          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),

           errmsg("operator family \"%s\" of access method %s contains operator %s with wrong signature",

              opfamilyname, "hash",

              format_operator(oprform->amopopr))));

      result = false;

    }

    /* There should be relevant hash functions for each datatype */

    if (!list_member_oid(hashabletypes, oprform->amoplefttype) ||

      !list_member_oid(hashabletypes, oprform->amoprighttype))

    {

      ereport(INFO,

          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),

           errmsg("operator family \"%s\" of access method %s lacks support function for operator %s",

              opfamilyname, "hash",

              format_operator(oprform->amopopr))));

      result = false;

    }

  }

  /* Now check for inconsistent groups of operators/functions */

  grouplist = identify_opfamily_groups(oprlist, proclist);

  opclassgroup = NULL;

  foreach(lc, grouplist)

  {

    OpFamilyOpFuncGroup *thisgroup = (OpFamilyOpFuncGroup *) lfirst(lc);

    /* Remember the group exactly matching the test opclass */

    if (thisgroup->lefttype == opcintype &&

      thisgroup->righttype == opcintype)

      opclassgroup = thisgroup;

    /*

     * Complain if there seems to be an incomplete set of operators for

     * this datatype pair (implying that we have a hash function but no

     * operator).

     */

    if (thisgroup->operatorset != (1 << HTEqualStrategyNumber))

    {

      ereport(INFO,

          (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),

           errmsg("operator family \"%s\" of access method %s is missing operator(s) for types %s and %s",

              opfamilyname, "hash",

              format_type_be(thisgroup->lefttype),

              format_type_be(thisgroup->righttype))));

      result = false;

    }

  }

  /* Check that the originally-named opclass is supported */

  /* (if group is there, we already checked it adequately above) */

  if (!opclassgroup)

  {

    ereport(INFO,

        (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),

         errmsg("operator class \"%s\" of access method %s is missing operator(s)",

            opclassname, "hash")));

    result = false;

  }

  /*

   * Complain if the opfamily doesn't have entries for all possible

   * combinations of its supported datatypes.  While missing cross-type

   * operators are not fatal, it seems reasonable to insist that all

   * built-in hash opfamilies be complete.

   */

  if (list_length(grouplist) !=

    list_length(hashabletypes) * list_length(hashabletypes))

  {

    ereport(INFO,

        (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),

         errmsg("operator family \"%s\" of access method %s is missing cross-type operator(s)",

            opfamilyname, "hash")));

    result = false;

  }

  ReleaseCatCacheList(proclist);

  ReleaseCatCacheList(oprlist);

  ReleaseSysCache(familytup);

  ReleaseSysCache(classtup);

  return result;

}

/*

 * We need a custom version of check_amproc_signature because of assorted

 * hacks in the core hash opclass definitions.

 */

static bool

check_hash_func_signature(Oid funcid, int16 amprocnum, Oid argtype)

{

  bool    result = true;

  Oid     restype;

  int16   nargs;

  HeapTuple tp;

  Form_pg_proc procform;

  switch (amprocnum)

  {

    case HASHSTANDARD_PROC:

      restype = INT4OID;

      nargs = 1;

      break;

    case HASHEXTENDED_PROC:

      restype = INT8OID;

      nargs = 2;

      break;

    default:

      elog(ERROR, "invalid amprocnum");

  }

  tp = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));

  if (!HeapTupleIsValid(tp))

    elog(ERROR, "cache lookup failed for function %u", funcid);

  procform = (Form_pg_proc) GETSTRUCT(tp);

  if (procform->prorettype != restype || procform->proretset ||

    procform->pronargs != nargs)

    result = false;

  if (!IsBinaryCoercible(argtype, procform->proargtypes.values[0]))

  {

    /*

     * Some of the built-in hash opclasses cheat by using hash functions

     * that are different from but physically compatible with the opclass

     * datatype.  In some of these cases, even a "binary coercible" check

     * fails because there's no relevant cast.  For the moment, fix it by

     * having a whitelist of allowed cases.  Test the specific function

     * identity, not just its input type, because hashvarlena() takes

     * INTERNAL and allowing any such function seems too scary.

     */

    if ((funcid == F_HASHINT4 || funcid == F_HASHINT4EXTENDED) &&

      (argtype == DATEOID ||

       argtype == ABSTIMEOID || argtype == RELTIMEOID ||

       argtype == XIDOID || argtype == CIDOID))

       /* okay, allowed use of hashint4() */ ;

    else if ((funcid == F_TIMESTAMP_HASH ||

          funcid == F_TIMESTAMP_HASH_EXTENDED) &&

         argtype == TIMESTAMPTZOID)

       /* okay, allowed use of timestamp_hash() */ ;

    else if ((funcid == F_HASHCHAR || funcid == F_HASHCHAREXTENDED) &&

         argtype == BOOLOID)

       /* okay, allowed use of hashchar() */ ;

    else if ((funcid == F_HASHVARLENA || funcid == F_HASHVARLENAEXTENDED) &&

         argtype == BYTEAOID)

       /* okay, allowed use of hashvarlena() */ ;

    else

      result = false;

  }

  /* If function takes a second argument, it must be for a 64-bit salt. */

  if (nargs == 2 && procform->proargtypes.values[1] != INT8OID)

    result = false;

  ReleaseSysCache(tp);

  return result;

}