src/backend/commands/operatorcmds.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * operatorcmds.c
   4  *
   5  *        Routines for operator manipulation commands
   6  *
   7  * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
   8  * Portions Copyright (c) 1994, Regents of the University of California
   9  *
  10  *
  11  * IDENTIFICATION
  12  *        $PostgreSQL$
  13  *
  14  * DESCRIPTION
  15  *        The "DefineFoo" routines take the parse tree and pick out the
  16  *        appropriate arguments/flags, passing the results to the
  17  *        corresponding "FooDefine" routines (in src/catalog) that do
  18  *        the actual catalog-munging.  These routines also verify permission
  19  *        of the user to execute the command.
  20  *
  21  * NOTES
  22  *        These things must be defined and committed in the following order:
  23  *              "create function":
  24  *                              input/output, recv/send procedures
  25  *              "create type":
  26  *                              type
  27  *              "create operator":
  28  *                              operators
  29  *
  30  *              Most of the parse-tree manipulation routines are defined in
  31  *              commands/manip.c.
  32  *
  33  *-------------------------------------------------------------------------
  34  */
  35 #include "postgres.h"
  36
  37 #include "access/heapam.h"
  38 #include "catalog/dependency.h"
  39 #include "catalog/indexing.h"
  40 #include "catalog/namespace.h"
  41 #include "catalog/pg_operator.h"
  42 #include "catalog/pg_type.h"
  43 #include "commands/defrem.h"
  44 #include "miscadmin.h"
  45 #include "parser/parse_func.h"
  46 #include "parser/parse_oper.h"
  47 #include "parser/parse_type.h"
  48 #include "utils/acl.h"
  49 #include "utils/lsyscache.h"
  50 #include "utils/rel.h"
  51 #include "utils/syscache.h"
  52
  53
  54 static void AlterOperatorOwner_internal(Relation rel, Oid operOid, Oid newOwnerId);
  55
  56 /*
  57  * DefineOperator
  58  *              this function extracts all the information from the
  59  *              parameter list generated by the parser and then has
  60  *              OperatorCreate() do all the actual work.
  61  *
  62  * 'parameters' is a list of DefElem
  63  */
  64 void
  65 DefineOperator(List *names, List *parameters)
  66 {
  67         char       *oprName;
  68         Oid                     oprNamespace;
  69         AclResult       aclresult;
  70         bool            canMerge = false;               /* operator merges */
  71         bool            canHash = false;        /* operator hashes */
  72         List       *functionName = NIL;         /* function for operator */
  73         TypeName   *typeName1 = NULL;           /* first type name */
  74         TypeName   *typeName2 = NULL;           /* second type name */
  75         Oid                     typeId1 = InvalidOid;   /* types converted to OID */
  76         Oid                     typeId2 = InvalidOid;
  77         List       *commutatorName = NIL;       /* optional commutator operator name */
  78         List       *negatorName = NIL;          /* optional negator operator name */
  79         List       *restrictionName = NIL;      /* optional restrict. sel. procedure */
  80         List       *joinName = NIL; /* optional join sel. procedure */
  81         Oid                     functionOid;    /* functions converted to OID */
  82         Oid                     restrictionOid;
  83         Oid                     joinOid;
  84         Oid                     typeId[5];              /* only need up to 5 args here */
  85         int                     nargs;
  86         ListCell   *pl;
  87
  88         /* Convert list of names to a name and namespace */
  89         oprNamespace = QualifiedNameGetCreationNamespace(names, &oprName);
  90
  91         /* Check we have creation rights in target namespace */
  92         aclresult = pg_namespace_aclcheck(oprNamespace, GetUserId(), ACL_CREATE);
  93         if (aclresult != ACLCHECK_OK)
  94                 aclcheck_error(aclresult, ACL_KIND_NAMESPACE,
  95                                            get_namespace_name(oprNamespace));
  96
  97         /*
  98          * loop over the definition list and extract the information we need.
  99          */
 100         foreach(pl, parameters)
 101         {
 102                 DefElem    *defel = (DefElem *) lfirst(pl);
 103
 104                 if (pg_strcasecmp(defel->defname, "leftarg") == 0)
 105                 {
 106                         typeName1 = defGetTypeName(defel);
 107                         if (typeName1->setof)
 108                                 ereport(ERROR,
 109                                                 (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 110                                         errmsg("SETOF type not allowed for operator argument")));
 111                 }
 112                 else if (pg_strcasecmp(defel->defname, "rightarg") == 0)
 113                 {
 114                         typeName2 = defGetTypeName(defel);
 115                         if (typeName2->setof)
 116                                 ereport(ERROR,
 117                                                 (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 118                                         errmsg("SETOF type not allowed for operator argument")));
 119                 }
 120                 else if (pg_strcasecmp(defel->defname, "procedure") == 0)
 121                         functionName = defGetQualifiedName(defel);
 122                 else if (pg_strcasecmp(defel->defname, "commutator") == 0)
 123                         commutatorName = defGetQualifiedName(defel);
 124                 else if (pg_strcasecmp(defel->defname, "negator") == 0)
 125                         negatorName = defGetQualifiedName(defel);
 126                 else if (pg_strcasecmp(defel->defname, "restrict") == 0)
 127                         restrictionName = defGetQualifiedName(defel);
 128                 else if (pg_strcasecmp(defel->defname, "join") == 0)
 129                         joinName = defGetQualifiedName(defel);
 130                 else if (pg_strcasecmp(defel->defname, "hashes") == 0)
 131                         canHash = defGetBoolean(defel);
 132                 else if (pg_strcasecmp(defel->defname, "merges") == 0)
 133                         canMerge = defGetBoolean(defel);
 134                 /* These obsolete options are taken as meaning canMerge */
 135                 else if (pg_strcasecmp(defel->defname, "sort1") == 0)
 136                         canMerge = true;
 137                 else if (pg_strcasecmp(defel->defname, "sort2") == 0)
 138                         canMerge = true;
 139                 else if (pg_strcasecmp(defel->defname, "ltcmp") == 0)
 140                         canMerge = true;
 141                 else if (pg_strcasecmp(defel->defname, "gtcmp") == 0)
 142                         canMerge = true;
 143                 else
 144                         ereport(WARNING,
 145                                         (errcode(ERRCODE_SYNTAX_ERROR),
 146                                          errmsg("operator attribute \"%s\" not recognized",
 147                                                         defel->defname)));
 148         }
 149
 150         /*
 151          * make sure we have our required definitions
 152          */
 153         if (functionName == NIL)
 154                 ereport(ERROR,
 155                                 (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 156                                  errmsg("operator procedure must be specified")));
 157
 158         /* Transform type names to type OIDs */
 159         if (typeName1)
 160                 typeId1 = typenameTypeId(NULL, typeName1, NULL);
 161         if (typeName2)
 162                 typeId2 = typenameTypeId(NULL, typeName2, NULL);
 163
 164         if (!OidIsValid(typeId1) && !OidIsValid(typeId2))
 165                 ereport(ERROR,
 166                                 (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
 167                    errmsg("at least one of leftarg or rightarg must be specified")));
 168
 169         /*
 170          * Look up the operator's underlying function.
 171          */
 172         if (!OidIsValid(typeId1))
 173         {
 174                 typeId[0] = typeId2;
 175                 nargs = 1;
 176         }
 177         else if (!OidIsValid(typeId2))
 178         {
 179                 typeId[0] = typeId1;
 180                 nargs = 1;
 181         }
 182         else
 183         {
 184                 typeId[0] = typeId1;
 185                 typeId[1] = typeId2;
 186                 nargs = 2;
 187         }
 188         functionOid = LookupFuncName(functionName, nargs, typeId, false);
 189
 190         /*
 191          * We require EXECUTE rights for the function.  This isn't strictly
 192          * necessary, since EXECUTE will be checked at any attempted use of the
 193          * operator, but it seems like a good idea anyway.
 194          */
 195         aclresult = pg_proc_aclcheck(functionOid, GetUserId(), ACL_EXECUTE);
 196         if (aclresult != ACLCHECK_OK)
 197                 aclcheck_error(aclresult, ACL_KIND_PROC,
 198                                            NameListToString(functionName));
 199
 200         /*
 201          * Look up restriction estimator if specified
 202          */
 203         if (restrictionName)
 204         {
 205                 typeId[0] = INTERNALOID;        /* PlannerInfo */
 206                 typeId[1] = OIDOID;             /* operator OID */
 207                 typeId[2] = INTERNALOID;        /* args list */
 208                 typeId[3] = INT4OID;    /* varRelid */
 209
 210                 restrictionOid = LookupFuncName(restrictionName, 4, typeId, false);
 211
 212                 /* estimators must return float8 */
 213                 if (get_func_rettype(restrictionOid) != FLOAT8OID)
 214                         ereport(ERROR,
 215                                         (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
 216                                          errmsg("restriction estimator function %s must return type \"float8\"",
 217                                                         NameListToString(restrictionName))));
 218
 219                 /* Require EXECUTE rights for the estimator */
 220                 aclresult = pg_proc_aclcheck(restrictionOid, GetUserId(), ACL_EXECUTE);
 221                 if (aclresult != ACLCHECK_OK)
 222                         aclcheck_error(aclresult, ACL_KIND_PROC,
 223                                                    NameListToString(restrictionName));
 224         }
 225         else
 226                 restrictionOid = InvalidOid;
 227
 228         /*
 229          * Look up join estimator if specified
 230          */
 231         if (joinName)
 232         {
 233                 typeId[0] = INTERNALOID;        /* PlannerInfo */
 234                 typeId[1] = OIDOID;             /* operator OID */
 235                 typeId[2] = INTERNALOID;        /* args list */
 236                 typeId[3] = INT2OID;    /* jointype */
 237                 typeId[4] = INTERNALOID;        /* SpecialJoinInfo */
 238
 239                 /*
 240                  * As of Postgres 8.4, the preferred signature for join estimators has
 241                  * 5 arguments, but we still allow the old 4-argument form. Try the
 242                  * preferred form first.
 243                  */
 244                 joinOid = LookupFuncName(joinName, 5, typeId, true);
 245                 if (!OidIsValid(joinOid))
 246                         joinOid = LookupFuncName(joinName, 4, typeId, true);
 247                 /* If not found, reference the 5-argument signature in error msg */
 248                 if (!OidIsValid(joinOid))
 249                         joinOid = LookupFuncName(joinName, 5, typeId, false);
 250
 251                 /* estimators must return float8 */
 252                 if (get_func_rettype(joinOid) != FLOAT8OID)
 253                         ereport(ERROR,
 254                                         (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
 255                          errmsg("join estimator function %s must return type \"float8\"",
 256                                         NameListToString(joinName))));
 257
 258                 /* Require EXECUTE rights for the estimator */
 259                 aclresult = pg_proc_aclcheck(joinOid, GetUserId(), ACL_EXECUTE);
 260                 if (aclresult != ACLCHECK_OK)
 261                         aclcheck_error(aclresult, ACL_KIND_PROC,
 262                                                    NameListToString(joinName));
 263         }
 264         else
 265                 joinOid = InvalidOid;
 266
 267         /*
 268          * now have OperatorCreate do all the work..
 269          */
 270         OperatorCreate(oprName,         /* operator name */
 271                                    oprNamespace,        /* namespace */
 272                                    typeId1,             /* left type id */
 273                                    typeId2,             /* right type id */
 274                                    functionOid, /* function for operator */
 275                                    commutatorName,              /* optional commutator operator name */
 276                                    negatorName, /* optional negator operator name */
 277                                    restrictionOid,              /* optional restrict. sel. procedure */
 278                                    joinOid,             /* optional join sel. procedure name */
 279                                    canMerge,    /* operator merges */
 280                                    canHash);    /* operator hashes */
 281 }
 282
 283
 284 /*
 285  * RemoveOperator
 286  *              Deletes an operator.
 287  */
 288 void
 289 RemoveOperator(RemoveFuncStmt *stmt)
 290 {
 291         List       *operatorName = stmt->name;
 292         TypeName   *typeName1 = (TypeName *) linitial(stmt->args);
 293         TypeName   *typeName2 = (TypeName *) lsecond(stmt->args);
 294         Oid                     operOid;
 295         HeapTuple       tup;
 296         ObjectAddress object;
 297
 298         Assert(list_length(stmt->args) == 2);
 299         operOid = LookupOperNameTypeNames(NULL, operatorName,
 300                                                                           typeName1, typeName2,
 301                                                                           stmt->missing_ok, -1);
 302
 303         if (stmt->missing_ok && !OidIsValid(operOid))
 304         {
 305                 ereport(NOTICE,
 306                                 (errmsg("operator %s does not exist, skipping",
 307                                                 NameListToString(operatorName))));
 308                 return;
 309         }
 310
 311         tup = SearchSysCache(OPEROID,
 312                                                  ObjectIdGetDatum(operOid),
 313                                                  0, 0, 0);
 314         if (!HeapTupleIsValid(tup)) /* should not happen */
 315                 elog(ERROR, "cache lookup failed for operator %u", operOid);
 316
 317         /* Permission check: must own operator or its namespace */
 318         if (!pg_oper_ownercheck(operOid, GetUserId()) &&
 319                 !pg_namespace_ownercheck(((Form_pg_operator) GETSTRUCT(tup))->oprnamespace,
 320                                                                  GetUserId()))
 321                 aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_OPER,
 322                                            NameListToString(operatorName));
 323
 324         ReleaseSysCache(tup);
 325
 326         /*
 327          * Do the deletion
 328          */
 329         object.classId = OperatorRelationId;
 330         object.objectId = operOid;
 331         object.objectSubId = 0;
 332
 333         performDeletion(&object, stmt->behavior);
 334 }
 335
 336 /*
 337  * Guts of operator deletion.
 338  */
 339 void
 340 RemoveOperatorById(Oid operOid)
 341 {
 342         Relation        relation;
 343         HeapTuple       tup;
 344
 345         relation = heap_open(OperatorRelationId, RowExclusiveLock);
 346
 347         tup = SearchSysCache(OPEROID,
 348                                                  ObjectIdGetDatum(operOid),
 349                                                  0, 0, 0);
 350         if (!HeapTupleIsValid(tup)) /* should not happen */
 351                 elog(ERROR, "cache lookup failed for operator %u", operOid);
 352
 353         simple_heap_delete(relation, &tup->t_self);
 354
 355         ReleaseSysCache(tup);
 356
 357         heap_close(relation, RowExclusiveLock);
 358 }
 359
 360 void
 361 AlterOperatorOwner_oid(Oid operOid, Oid newOwnerId)
 362 {
 363         Relation        rel;
 364
 365         rel = heap_open(OperatorRelationId, RowExclusiveLock);
 366
 367         AlterOperatorOwner_internal(rel, operOid, newOwnerId);
 368
 369         heap_close(rel, NoLock);
 370 }
 371
 372 /*
 373  * change operator owner
 374  */
 375 void
 376 AlterOperatorOwner(List *name, TypeName *typeName1, TypeName *typeName2,
 377                                    Oid newOwnerId)
 378 {
 379         Oid                     operOid;
 380         Relation        rel;
 381
 382         rel = heap_open(OperatorRelationId, RowExclusiveLock);
 383
 384         operOid = LookupOperNameTypeNames(NULL, name,
 385                                                                           typeName1, typeName2,
 386                                                                           false, -1);
 387
 388         AlterOperatorOwner_internal(rel, operOid, newOwnerId);
 389
 390         heap_close(rel, NoLock);
 391 }
 392
 393 static void
 394 AlterOperatorOwner_internal(Relation rel, Oid operOid, Oid newOwnerId)
 395 {
 396         HeapTuple       tup;
 397         AclResult       aclresult;
 398         Form_pg_operator oprForm;
 399
 400         Assert(RelationGetRelid(rel) == OperatorRelationId);
 401
 402         tup = SearchSysCacheCopy(OPEROID,
 403                                                          ObjectIdGetDatum(operOid),
 404                                                          0, 0, 0);
 405         if (!HeapTupleIsValid(tup)) /* should not happen */
 406                 elog(ERROR, "cache lookup failed for operator %u", operOid);
 407
 408         oprForm = (Form_pg_operator) GETSTRUCT(tup);
 409
 410         /*
 411          * If the new owner is the same as the existing owner, consider the
 412          * command to have succeeded.  This is for dump restoration purposes.
 413          */
 414         if (oprForm->oprowner != newOwnerId)
 415         {
 416                 /* Superusers can always do it */
 417                 if (!superuser())
 418                 {
 419                         /* Otherwise, must be owner of the existing object */
 420                         if (!pg_oper_ownercheck(operOid, GetUserId()))
 421                                 aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_OPER,
 422                                                            NameStr(oprForm->oprname));
 423
 424                         /* Must be able to become new owner */
 425                         check_is_member_of_role(GetUserId(), newOwnerId);
 426
 427                         /* New owner must have CREATE privilege on namespace */
 428                         aclresult = pg_namespace_aclcheck(oprForm->oprnamespace,
 429                                                                                           newOwnerId,
 430                                                                                           ACL_CREATE);
 431                         if (aclresult != ACLCHECK_OK)
 432                                 aclcheck_error(aclresult, ACL_KIND_NAMESPACE,
 433                                                            get_namespace_name(oprForm->oprnamespace));
 434                 }
 435
 436                 /*
 437                  * Modify the owner --- okay to scribble on tup because it's a copy
 438                  */
 439                 oprForm->oprowner = newOwnerId;
 440
 441                 simple_heap_update(rel, &tup->t_self, tup);
 442
 443                 CatalogUpdateIndexes(rel, tup);
 444
 445                 /* Update owner dependency reference */
 446                 changeDependencyOnOwner(OperatorRelationId, operOid, newOwnerId);
 447         }
 448
 449         heap_freetuple(tup);
 450 }