+++ /dev/null
-/*-------------------------------------------------------------------------
- *
- * rewriteDefine.c
- * routines for defining a rewrite rule
- *
- * Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- *
- * IDENTIFICATION
- * src/backend/rewrite/rewriteDefine.c
- *
- *-------------------------------------------------------------------------
- */
-#include "postgres.h"
-
-#include "access/heapam.h"
-#include "access/htup_details.h"
-#include "access/multixact.h"
-#include "access/transam.h"
-#include "access/xact.h"
-#include "catalog/catalog.h"
-#include "catalog/dependency.h"
-#include "catalog/heap.h"
-#include "catalog/indexing.h"
-#include "catalog/namespace.h"
-#include "catalog/objectaccess.h"
-#include "catalog/pg_rewrite.h"
-#include "catalog/storage.h"
-#include "miscadmin.h"
-#include "nodes/nodeFuncs.h"
-#include "parser/parse_utilcmd.h"
-#include "rewrite/rewriteDefine.h"
-#include "rewrite/rewriteManip.h"
-#include "rewrite/rewriteSupport.h"
-#include "utils/acl.h"
-#include "utils/builtins.h"
-#include "utils/inval.h"
-#include "utils/lsyscache.h"
-#include "utils/rel.h"
-#include "utils/syscache.h"
-#include "utils/tqual.h"
-
-
-static void checkRuleResultList(List *targetList, TupleDesc resultDesc,
- bool isSelect);
-static bool setRuleCheckAsUser_walker(Node *node, Oid *context);
-static void setRuleCheckAsUser_Query(Query *qry, Oid userid);
-
-
-/*
- * InsertRule -
- * takes the arguments and inserts them as a row into the system
- * relation "pg_rewrite"
- */
-static Oid
-InsertRule(char *rulname,
- int evtype,
- Oid eventrel_oid,
- AttrNumber evslot_index,
- bool evinstead,
- Node *event_qual,
- List *action,
- bool replace)
-{
- char *evqual = nodeToString(event_qual);
- char *actiontree = nodeToString((Node *) action);
- Datum values[Natts_pg_rewrite];
- bool nulls[Natts_pg_rewrite];
- bool replaces[Natts_pg_rewrite];
- NameData rname;
- Relation pg_rewrite_desc;
- HeapTuple tup,
- oldtup;
- Oid rewriteObjectId;
- ObjectAddress myself,
- referenced;
- bool is_update = false;
-
- /*
- * Set up *nulls and *values arrays
- */
- MemSet(nulls, false, sizeof(nulls));
-
- namestrcpy(&rname, rulname);
- values[Anum_pg_rewrite_rulename - 1] = NameGetDatum(&rname);
- values[Anum_pg_rewrite_ev_class - 1] = ObjectIdGetDatum(eventrel_oid);
- values[Anum_pg_rewrite_ev_attr - 1] = Int16GetDatum(evslot_index);
- values[Anum_pg_rewrite_ev_type - 1] = CharGetDatum(evtype + '0');
- values[Anum_pg_rewrite_ev_enabled - 1] = CharGetDatum(RULE_FIRES_ON_ORIGIN);
- values[Anum_pg_rewrite_is_instead - 1] = BoolGetDatum(evinstead);
- values[Anum_pg_rewrite_ev_qual - 1] = CStringGetTextDatum(evqual);
- values[Anum_pg_rewrite_ev_action - 1] = CStringGetTextDatum(actiontree);
-
- /*
- * Ready to store new pg_rewrite tuple
- */
- pg_rewrite_desc = heap_open(RewriteRelationId, RowExclusiveLock);
-
- /*
- * Check to see if we are replacing an existing tuple
- */
- oldtup = SearchSysCache2(RULERELNAME,
- ObjectIdGetDatum(eventrel_oid),
- PointerGetDatum(rulname));
-
- if (HeapTupleIsValid(oldtup))
- {
- if (!replace)
- ereport(ERROR,
- (errcode(ERRCODE_DUPLICATE_OBJECT),
- errmsg("rule \"%s\" for relation \"%s\" already exists",
- rulname, get_rel_name(eventrel_oid))));
-
- /*
- * When replacing, we don't need to replace every attribute
- */
- MemSet(replaces, false, sizeof(replaces));
- replaces[Anum_pg_rewrite_ev_attr - 1] = true;
- replaces[Anum_pg_rewrite_ev_type - 1] = true;
- replaces[Anum_pg_rewrite_is_instead - 1] = true;
- replaces[Anum_pg_rewrite_ev_qual - 1] = true;
- replaces[Anum_pg_rewrite_ev_action - 1] = true;
-
- tup = heap_modify_tuple(oldtup, RelationGetDescr(pg_rewrite_desc),
- values, nulls, replaces);
-
- simple_heap_update(pg_rewrite_desc, &tup->t_self, tup);
-
- ReleaseSysCache(oldtup);
-
- rewriteObjectId = HeapTupleGetOid(tup);
- is_update = true;
- }
- else
- {
- tup = heap_form_tuple(pg_rewrite_desc->rd_att, values, nulls);
-
- rewriteObjectId = simple_heap_insert(pg_rewrite_desc, tup);
- }
-
- /* Need to update indexes in either case */
- CatalogUpdateIndexes(pg_rewrite_desc, tup);
-
- heap_freetuple(tup);
-
- /* If replacing, get rid of old dependencies and make new ones */
- if (is_update)
- deleteDependencyRecordsFor(RewriteRelationId, rewriteObjectId, false);
-
- /*
- * Install dependency on rule's relation to ensure it will go away on
- * relation deletion. If the rule is ON SELECT, make the dependency
- * implicit --- this prevents deleting a view's SELECT rule. Other kinds
- * of rules can be AUTO.
- */
- myself.classId = RewriteRelationId;
- myself.objectId = rewriteObjectId;
- myself.objectSubId = 0;
-
- referenced.classId = RelationRelationId;
- referenced.objectId = eventrel_oid;
- referenced.objectSubId = 0;
-
- recordDependencyOn(&myself, &referenced,
- (evtype == CMD_SELECT) ? DEPENDENCY_INTERNAL : DEPENDENCY_AUTO);
-
- /*
- * Also install dependencies on objects referenced in action and qual.
- */
- recordDependencyOnExpr(&myself, (Node *) action, NIL,
- DEPENDENCY_NORMAL);
-
- if (event_qual != NULL)
- {
- /* Find query containing OLD/NEW rtable entries */
- Query *qry = (Query *) linitial(action);
-
- qry = getInsertSelectQuery(qry, NULL);
- recordDependencyOnExpr(&myself, event_qual, qry->rtable,
- DEPENDENCY_NORMAL);
- }
-
- /* Post creation hook for new rule */
- InvokeObjectAccessHook(OAT_POST_CREATE,
- RewriteRelationId, rewriteObjectId, 0, NULL);
-
- heap_close(pg_rewrite_desc, RowExclusiveLock);
-
- return rewriteObjectId;
-}
-
-/*
- * DefineRule
- * Execute a CREATE RULE command.
- */
-Oid
-DefineRule(RuleStmt *stmt, const char *queryString)
-{
- List *actions;
- Node *whereClause;
- Oid relId;
-
- /* Parse analysis. */
- transformRuleStmt(stmt, queryString, &actions, &whereClause);
-
- /*
- * Find and lock the relation. Lock level should match
- * DefineQueryRewrite.
- */
- relId = RangeVarGetRelid(stmt->relation, AccessExclusiveLock, false);
-
- /* ... and execute */
- return DefineQueryRewrite(stmt->rulename,
- relId,
- whereClause,
- stmt->event,
- stmt->instead,
- stmt->replace,
- actions);
-}
-
-
-/*
- * DefineQueryRewrite
- * Create a rule
- *
- * This is essentially the same as DefineRule() except that the rule's
- * action and qual have already been passed through parse analysis.
- */
-Oid
-DefineQueryRewrite(char *rulename,
- Oid event_relid,
- Node *event_qual,
- CmdType event_type,
- bool is_instead,
- bool replace,
- List *action)
-{
- Relation event_relation;
- int event_attno;
- ListCell *l;
- Query *query;
- bool RelisBecomingView = false;
- Oid ruleId = InvalidOid;
-
- /*
- * If we are installing an ON SELECT rule, we had better grab
- * AccessExclusiveLock to ensure no SELECTs are currently running on the
- * event relation. For other types of rules, it would be sufficient to
- * grab ShareRowExclusiveLock to lock out insert/update/delete actions and
- * to ensure that we lock out current CREATE RULE statements; but because
- * of race conditions in access to catalog entries, we can't do that yet.
- *
- * Note that this lock level should match the one used in DefineRule.
- */
- event_relation = heap_open(event_relid, AccessExclusiveLock);
-
- /*
- * Verify relation is of a type that rules can sensibly be applied to.
- */
- if (event_relation->rd_rel->relkind != RELKIND_RELATION &&
- event_relation->rd_rel->relkind != RELKIND_VIEW)
- ereport(ERROR,
- (errcode(ERRCODE_WRONG_OBJECT_TYPE),
- errmsg("\"%s\" is not a table or view",
- RelationGetRelationName(event_relation))));
-
- if (!allowSystemTableMods && IsSystemRelation(event_relation))
- ereport(ERROR,
- (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
- errmsg("permission denied: \"%s\" is a system catalog",
- RelationGetRelationName(event_relation))));
-
- /*
- * Check user has permission to apply rules to this relation.
- */
- if (!pg_class_ownercheck(event_relid, GetUserId()))
- aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
- RelationGetRelationName(event_relation));
-
- /*
- * No rule actions that modify OLD or NEW
- */
- foreach(l, action)
- {
- query = (Query *) lfirst(l);
- if (query->resultRelation == 0)
- continue;
- /* Don't be fooled by INSERT/SELECT */
- if (query != getInsertSelectQuery(query, NULL))
- continue;
- if (query->resultRelation == PRS2_OLD_VARNO)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("rule actions on OLD are not implemented"),
- errhint("Use views or triggers instead.")));
- if (query->resultRelation == PRS2_NEW_VARNO)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("rule actions on NEW are not implemented"),
- errhint("Use triggers instead.")));
- }
-
- if (event_type == CMD_SELECT)
- {
- /*
- * Rules ON SELECT are restricted to view definitions
- *
- * So there cannot be INSTEAD NOTHING, ...
- */
- if (list_length(action) == 0)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("INSTEAD NOTHING rules on SELECT are not implemented"),
- errhint("Use views instead.")));
-
- /*
- * ... there cannot be multiple actions, ...
- */
- if (list_length(action) > 1)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("multiple actions for rules on SELECT are not implemented")));
-
- /*
- * ... the one action must be a SELECT, ...
- */
- query = (Query *) linitial(action);
- if (!is_instead ||
- query->commandType != CMD_SELECT ||
- query->utilityStmt != NULL)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("rules on SELECT must have action INSTEAD SELECT")));
-
- /*
- * ... it cannot contain data-modifying WITH ...
- */
- if (query->hasModifyingCTE)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("rules on SELECT must not contain data-modifying statements in WITH")));
-
- /*
- * ... there can be no rule qual, ...
- */
- if (event_qual != NULL)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("event qualifications are not implemented for rules on SELECT")));
-
- /*
- * ... the targetlist of the SELECT action must exactly match the
- * event relation, ...
- */
- checkRuleResultList(query->targetList,
- RelationGetDescr(event_relation),
- true);
-
- /*
- * ... there must not be another ON SELECT rule already ...
- */
- if (!replace && event_relation->rd_rules != NULL)
- {
- int i;
-
- for (i = 0; i < event_relation->rd_rules->numLocks; i++)
- {
- RewriteRule *rule;
-
- rule = event_relation->rd_rules->rules[i];
- if (rule->event == CMD_SELECT)
- ereport(ERROR,
- (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
- errmsg("\"%s\" is already a view",
- RelationGetRelationName(event_relation))));
- }
- }
-
- /*
- * ... and finally the rule must be named _RETURN.
- */
- if (strcmp(rulename, ViewSelectRuleName) != 0)
- {
- /*
- * In versions before 7.3, the expected name was _RETviewname. For
- * backwards compatibility with old pg_dump output, accept that
- * and silently change it to _RETURN. Since this is just a quick
- * backwards-compatibility hack, limit the number of characters
- * checked to a few less than NAMEDATALEN; this saves having to
- * worry about where a multibyte character might have gotten
- * truncated.
- */
- if (strncmp(rulename, "_RET", 4) != 0 ||
- strncmp(rulename + 4, RelationGetRelationName(event_relation),
- NAMEDATALEN - 4 - 4) != 0)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
- errmsg("view rule for \"%s\" must be named \"%s\"",
- RelationGetRelationName(event_relation),
- ViewSelectRuleName)));
- rulename = pstrdup(ViewSelectRuleName);
- }
-
- /*
- * Are we converting a relation to a view?
- *
- * If so, check that the relation is empty because the storage for the
- * relation is going to be deleted. Also insist that the rel not have
- * any triggers, indexes, or child tables. (Note: these tests are too
- * strict, because they will reject relations that once had such but
- * don't anymore. But we don't really care, because this whole
- * business of converting relations to views is just a kluge to allow
- * dump/reload of views that participate in circular dependencies.)
- */
- if (event_relation->rd_rel->relkind != RELKIND_VIEW)
- {
- HeapScanDesc scanDesc;
-
- scanDesc = heap_beginscan(event_relation, SnapshotNow, 0, NULL);
- if (heap_getnext(scanDesc, ForwardScanDirection) != NULL)
- ereport(ERROR,
- (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
- errmsg("could not convert table \"%s\" to a view because it is not empty",
- RelationGetRelationName(event_relation))));
- heap_endscan(scanDesc);
-
- if (event_relation->rd_rel->relhastriggers)
- ereport(ERROR,
- (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
- errmsg("could not convert table \"%s\" to a view because it has triggers",
- RelationGetRelationName(event_relation)),
- errhint("In particular, the table cannot be involved in any foreign key relationships.")));
-
- if (event_relation->rd_rel->relhasindex)
- ereport(ERROR,
- (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
- errmsg("could not convert table \"%s\" to a view because it has indexes",
- RelationGetRelationName(event_relation))));
-
- if (event_relation->rd_rel->relhassubclass)
- ereport(ERROR,
- (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
- errmsg("could not convert table \"%s\" to a view because it has child tables",
- RelationGetRelationName(event_relation))));
-
- RelisBecomingView = true;
- }
- }
- else
- {
- /*
- * For non-SELECT rules, a RETURNING list can appear in at most one of
- * the actions ... and there can't be any RETURNING list at all in a
- * conditional or non-INSTEAD rule. (Actually, there can be at most
- * one RETURNING list across all rules on the same event, but it seems
- * best to enforce that at rule expansion time.) If there is a
- * RETURNING list, it must match the event relation.
- */
- bool haveReturning = false;
-
- foreach(l, action)
- {
- query = (Query *) lfirst(l);
-
- if (!query->returningList)
- continue;
- if (haveReturning)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("cannot have multiple RETURNING lists in a rule")));
- haveReturning = true;
- if (event_qual != NULL)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("RETURNING lists are not supported in conditional rules")));
- if (!is_instead)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("RETURNING lists are not supported in non-INSTEAD rules")));
- checkRuleResultList(query->returningList,
- RelationGetDescr(event_relation),
- false);
- }
- }
-
- /*
- * This rule is allowed - prepare to install it.
- */
- event_attno = -1;
-
- /* discard rule if it's null action and not INSTEAD; it's a no-op */
- if (action != NIL || is_instead)
- {
- ruleId = InsertRule(rulename,
- event_type,
- event_relid,
- event_attno,
- is_instead,
- event_qual,
- action,
- replace);
-
- /*
- * Set pg_class 'relhasrules' field TRUE for event relation.
- *
- * Important side effect: an SI notice is broadcast to force all
- * backends (including me!) to update relcache entries with the new
- * rule.
- */
- SetRelationRuleStatus(event_relid, true);
- }
-
- /* ---------------------------------------------------------------------
- * If the relation is becoming a view:
- * - delete the associated storage files
- * - get rid of any system attributes in pg_attribute; a view shouldn't
- * have any of those
- * - remove the toast table; there is no need for it anymore, and its
- * presence would make vacuum slightly more complicated
- * - set relkind to RELKIND_VIEW, and adjust other pg_class fields
- * to be appropriate for a view
- *
- * NB: we had better have AccessExclusiveLock to do this ...
- * ---------------------------------------------------------------------
- */
- if (RelisBecomingView)
- {
- Relation relationRelation;
- Oid toastrelid;
- HeapTuple classTup;
- Form_pg_class classForm;
-
- relationRelation = heap_open(RelationRelationId, RowExclusiveLock);
- toastrelid = event_relation->rd_rel->reltoastrelid;
-
- /* drop storage while table still looks like a table */
- RelationDropStorage(event_relation);
- DeleteSystemAttributeTuples(event_relid);
-
- /*
- * Drop the toast table if any. (This won't take care of updating
- * the toast fields in the relation's own pg_class entry; we handle
- * that below.)
- */
- if (OidIsValid(toastrelid))
- {
- ObjectAddress toastobject;
-
- /*
- * Delete the dependency of the toast relation on the main
- * relation so we can drop the former without dropping the latter.
- */
- deleteDependencyRecordsFor(RelationRelationId, toastrelid,
- false);
-
- /* Make deletion of dependency record visible */
- CommandCounterIncrement();
-
- /* Now drop toast table, including its index */
- toastobject.classId = RelationRelationId;
- toastobject.objectId = toastrelid;
- toastobject.objectSubId = 0;
- performDeletion(&toastobject, DROP_RESTRICT,
- PERFORM_DELETION_INTERNAL);
- }
-
- /*
- * SetRelationRuleStatus may have updated the pg_class row, so we must
- * advance the command counter before trying to update it again.
- */
- CommandCounterIncrement();
-
- /*
- * Fix pg_class entry to look like a normal view's, including setting
- * the correct relkind and removal of reltoastrelid/reltoastidxid of
- * the toast table we potentially removed above.
- */
- classTup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(event_relid));
- if (!HeapTupleIsValid(classTup))
- elog(ERROR, "cache lookup failed for relation %u", event_relid);
- classForm = (Form_pg_class) GETSTRUCT(classTup);
-
- classForm->reltablespace = InvalidOid;
- classForm->relpages = 0;
- classForm->reltuples = 0;
- classForm->relallvisible = 0;
- classForm->reltoastrelid = InvalidOid;
- classForm->reltoastidxid = InvalidOid;
- classForm->relhasindex = false;
- classForm->relkind = RELKIND_VIEW;
- classForm->relhasoids = false;
- classForm->relhaspkey = false;
- classForm->relfrozenxid = InvalidTransactionId;
- classForm->relminmxid = InvalidMultiXactId;
-
- simple_heap_update(relationRelation, &classTup->t_self, classTup);
- CatalogUpdateIndexes(relationRelation, classTup);
-
- heap_freetuple(classTup);
- heap_close(relationRelation, RowExclusiveLock);
- }
-
- /* Close rel, but keep lock till commit... */
- heap_close(event_relation, NoLock);
-
- return ruleId;
-}
-
-/*
- * checkRuleResultList
- * Verify that targetList produces output compatible with a tupledesc
- *
- * The targetList might be either a SELECT targetlist, or a RETURNING list;
- * isSelect tells which. (This is mostly used for choosing error messages,
- * but also we don't enforce column name matching for RETURNING.)
- */
-static void
-checkRuleResultList(List *targetList, TupleDesc resultDesc, bool isSelect)
-{
- ListCell *tllist;
- int i;
-
- i = 0;
- foreach(tllist, targetList)
- {
- TargetEntry *tle = (TargetEntry *) lfirst(tllist);
- int32 tletypmod;
- Form_pg_attribute attr;
- char *attname;
-
- /* resjunk entries may be ignored */
- if (tle->resjunk)
- continue;
- i++;
- if (i > resultDesc->natts)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
- isSelect ?
- errmsg("SELECT rule's target list has too many entries") :
- errmsg("RETURNING list has too many entries")));
-
- attr = resultDesc->attrs[i - 1];
- attname = NameStr(attr->attname);
-
- /*
- * Disallow dropped columns in the relation. This won't happen in the
- * cases we actually care about (namely creating a view via CREATE
- * TABLE then CREATE RULE, or adding a RETURNING rule to a view).
- * Trying to cope with it is much more trouble than it's worth,
- * because we'd have to modify the rule to insert dummy NULLs at the
- * right positions.
- */
- if (attr->attisdropped)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("cannot convert relation containing dropped columns to view")));
-
- if (isSelect && strcmp(tle->resname, attname) != 0)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
- errmsg("SELECT rule's target entry %d has different column name from \"%s\"", i, attname)));
-
- if (attr->atttypid != exprType((Node *) tle->expr))
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
- isSelect ?
- errmsg("SELECT rule's target entry %d has different type from column \"%s\"",
- i, attname) :
- errmsg("RETURNING list's entry %d has different type from column \"%s\"",
- i, attname)));
-
- /*
- * Allow typmods to be different only if one of them is -1, ie,
- * "unspecified". This is necessary for cases like "numeric", where
- * the table will have a filled-in default length but the select
- * rule's expression will probably have typmod = -1.
- */
- tletypmod = exprTypmod((Node *) tle->expr);
- if (attr->atttypmod != tletypmod &&
- attr->atttypmod != -1 && tletypmod != -1)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
- isSelect ?
- errmsg("SELECT rule's target entry %d has different size from column \"%s\"",
- i, attname) :
- errmsg("RETURNING list's entry %d has different size from column \"%s\"",
- i, attname)));
- }
-
- if (i != resultDesc->natts)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
- isSelect ?
- errmsg("SELECT rule's target list has too few entries") :
- errmsg("RETURNING list has too few entries")));
-}
-
-/*
- * setRuleCheckAsUser
- * Recursively scan a query or expression tree and set the checkAsUser
- * field to the given userid in all rtable entries.
- *
- * Note: for a view (ON SELECT rule), the checkAsUser field of the OLD
- * RTE entry will be overridden when the view rule is expanded, and the
- * checkAsUser field of the NEW entry is irrelevant because that entry's
- * requiredPerms bits will always be zero. However, for other types of rules
- * it's important to set these fields to match the rule owner. So we just set
- * them always.
- */
-void
-setRuleCheckAsUser(Node *node, Oid userid)
-{
- (void) setRuleCheckAsUser_walker(node, &userid);
-}
-
-static bool
-setRuleCheckAsUser_walker(Node *node, Oid *context)
-{
- if (node == NULL)
- return false;
- if (IsA(node, Query))
- {
- setRuleCheckAsUser_Query((Query *) node, *context);
- return false;
- }
- return expression_tree_walker(node, setRuleCheckAsUser_walker,
- (void *) context);
-}
-
-static void
-setRuleCheckAsUser_Query(Query *qry, Oid userid)
-{
- ListCell *l;
-
- /* Set all the RTEs in this query node */
- foreach(l, qry->rtable)
- {
- RangeTblEntry *rte = (RangeTblEntry *) lfirst(l);
-
- if (rte->rtekind == RTE_SUBQUERY)
- {
- /* Recurse into subquery in FROM */
- setRuleCheckAsUser_Query(rte->subquery, userid);
- }
- else
- rte->checkAsUser = userid;
- }
-
- /* Recurse into subquery-in-WITH */
- foreach(l, qry->cteList)
- {
- CommonTableExpr *cte = (CommonTableExpr *) lfirst(l);
-
- setRuleCheckAsUser_Query((Query *) cte->ctequery, userid);
- }
-
- /* If there are sublinks, search for them and process their RTEs */
- if (qry->hasSubLinks)
- query_tree_walker(qry, setRuleCheckAsUser_walker, (void *) &userid,
- QTW_IGNORE_RC_SUBQUERIES);
-}
-
-
-/*
- * Change the firing semantics of an existing rule.
- */
-void
-EnableDisableRule(Relation rel, const char *rulename,
- char fires_when)
-{
- Relation pg_rewrite_desc;
- Oid owningRel = RelationGetRelid(rel);
- Oid eventRelationOid;
- HeapTuple ruletup;
- bool changed = false;
-
- /*
- * Find the rule tuple to change.
- */
- pg_rewrite_desc = heap_open(RewriteRelationId, RowExclusiveLock);
- ruletup = SearchSysCacheCopy2(RULERELNAME,
- ObjectIdGetDatum(owningRel),
- PointerGetDatum(rulename));
- if (!HeapTupleIsValid(ruletup))
- ereport(ERROR,
- (errcode(ERRCODE_UNDEFINED_OBJECT),
- errmsg("rule \"%s\" for relation \"%s\" does not exist",
- rulename, get_rel_name(owningRel))));
-
- /*
- * Verify that the user has appropriate permissions.
- */
- eventRelationOid = ((Form_pg_rewrite) GETSTRUCT(ruletup))->ev_class;
- Assert(eventRelationOid == owningRel);
- if (!pg_class_ownercheck(eventRelationOid, GetUserId()))
- aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS,
- get_rel_name(eventRelationOid));
-
- /*
- * Change ev_enabled if it is different from the desired new state.
- */
- if (DatumGetChar(((Form_pg_rewrite) GETSTRUCT(ruletup))->ev_enabled) !=
- fires_when)
- {
- ((Form_pg_rewrite) GETSTRUCT(ruletup))->ev_enabled =
- CharGetDatum(fires_when);
- simple_heap_update(pg_rewrite_desc, &ruletup->t_self, ruletup);
-
- /* keep system catalog indexes current */
- CatalogUpdateIndexes(pg_rewrite_desc, ruletup);
-
- changed = true;
- }
-
- heap_freetuple(ruletup);
- heap_close(pg_rewrite_desc, RowExclusiveLock);
-
- /*
- * If we changed anything, broadcast a SI inval message to force each
- * backend (including our own!) to rebuild relation's relcache entry.
- * Otherwise they will fail to apply the change promptly.
- */
- if (changed)
- CacheInvalidateRelcache(rel);
-}
-
-
-/*
- * Perform permissions and integrity checks before acquiring a relation lock.
- */
-static void
-RangeVarCallbackForRenameRule(const RangeVar *rv, Oid relid, Oid oldrelid,
- void *arg)
-{
- HeapTuple tuple;
- Form_pg_class form;
-
- tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
- if (!HeapTupleIsValid(tuple))
- return; /* concurrently dropped */
- form = (Form_pg_class) GETSTRUCT(tuple);
-
- /* only tables and views can have rules */
- if (form->relkind != RELKIND_RELATION && form->relkind != RELKIND_VIEW)
- ereport(ERROR,
- (errcode(ERRCODE_WRONG_OBJECT_TYPE),
- errmsg("\"%s\" is not a table or view", rv->relname)));
-
- if (!allowSystemTableMods && IsSystemClass(form))
- ereport(ERROR,
- (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
- errmsg("permission denied: \"%s\" is a system catalog",
- rv->relname)));
-
- /* you must own the table to rename one of its rules */
- if (!pg_class_ownercheck(relid, GetUserId()))
- aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS, rv->relname);
-
- ReleaseSysCache(tuple);
-}
-
-/*
- * Rename an existing rewrite rule.
- */
-Oid
-RenameRewriteRule(RangeVar *relation, const char *oldName,
- const char *newName)
-{
- Oid relid;
- Relation targetrel;
- Relation pg_rewrite_desc;
- HeapTuple ruletup;
- Form_pg_rewrite ruleform;
- Oid ruleOid;
-
- /*
- * Look up name, check permissions, and acquire lock (which we will NOT
- * release until end of transaction).
- */
- relid = RangeVarGetRelidExtended(relation, AccessExclusiveLock,
- false, false,
- RangeVarCallbackForRenameRule,
- NULL);
-
- /* Have lock already, so just need to build relcache entry. */
- targetrel = relation_open(relid, NoLock);
-
- /* Prepare to modify pg_rewrite */
- pg_rewrite_desc = heap_open(RewriteRelationId, RowExclusiveLock);
-
- /* Fetch the rule's entry (it had better exist) */
- ruletup = SearchSysCacheCopy2(RULERELNAME,
- ObjectIdGetDatum(relid),
- PointerGetDatum(oldName));
- if (!HeapTupleIsValid(ruletup))
- ereport(ERROR,
- (errcode(ERRCODE_UNDEFINED_OBJECT),
- errmsg("rule \"%s\" for relation \"%s\" does not exist",
- oldName, RelationGetRelationName(targetrel))));
- ruleform = (Form_pg_rewrite) GETSTRUCT(ruletup);
- ruleOid = HeapTupleGetOid(ruletup);
-
- /* rule with the new name should not already exist */
- if (IsDefinedRewriteRule(relid, newName))
- ereport(ERROR,
- (errcode(ERRCODE_DUPLICATE_OBJECT),
- errmsg("rule \"%s\" for relation \"%s\" already exists",
- newName, RelationGetRelationName(targetrel))));
-
- /*
- * We disallow renaming ON SELECT rules, because they should always be
- * named "_RETURN".
- */
- if (ruleform->ev_type == CMD_SELECT + '0')
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
- errmsg("renaming an ON SELECT rule is not allowed")));
-
- /* OK, do the update */
- namestrcpy(&(ruleform->rulename), newName);
-
- simple_heap_update(pg_rewrite_desc, &ruletup->t_self, ruletup);
-
- /* keep system catalog indexes current */
- CatalogUpdateIndexes(pg_rewrite_desc, ruletup);
-
- heap_freetuple(ruletup);
- heap_close(pg_rewrite_desc, RowExclusiveLock);
-
- /*
- * Invalidate relation's relcache entry so that other backends (and this
- * one too!) are sent SI message to make them rebuild relcache entries.
- * (Ideally this should happen automatically...)
- */
- CacheInvalidateRelcache(targetrel);
-
- /*
- * Close rel, but keep exclusive lock!
- */
- relation_close(targetrel, NoLock);
-
- return ruleOid;
-}
projects / postgresql.git / commitdiff