SELECT FOR UPDATE is implemented...

src/backend/executor/execMain.c

@@ -26,7 +26,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/executor/execMain.c,v 1.62 1998/12/18 09:10:21 vadim Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/executor/execMain.c,v 1.63 1999/01/25 12:01:03 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -363,6 +363,32 @@ ExecCheckPerms(CmdType operation,
 	}
 	if (!ok)
 		elog(ERROR, "%s: %s", rname.data, aclcheck_error_strings[aclcheck_result]);
+
+	if (parseTree->rowMark != NULL)
+	{
+		foreach(lp, parseTree->rowMark)
+		{
+			RowMark	   *rm = lfirst(lp);
+
+			if (!(rm->info & ROW_ACL_FOR_UPDATE))
+				continue;
+
+			relid = ((RangeTblEntry *)nth(rm->rti - 1, rangeTable))->relid;
+			htup = SearchSysCacheTuple(RELOID,
+								   ObjectIdGetDatum(relid),
+								   0, 0, 0);
+			if (!HeapTupleIsValid(htup))
+				elog(ERROR, "ExecCheckPerms: bogus RT relid: %d",
+					 relid);
+			StrNCpy(rname.data,
+					((Form_pg_class) GETSTRUCT(htup))->relname.data,
+					NAMEDATALEN);
+			ok = ((aclcheck_result = CHECK(ACL_WR)) == ACLCHECK_OK);
+			opstr = "write";
+			if (!ok)
+				elog(ERROR, "%s: %s", rname.data, aclcheck_error_strings[aclcheck_result]);
+		}
+	}
 }
 
 /* ===============================================================
@@ -372,6 +398,11 @@ ExecCheckPerms(CmdType operation,
  * ===============================================================
  */
 
+typedef struct execRowMark
+{
+	Relation	relation;
+	char		resname[32];
+} execRowMark;
 
 /* ----------------------------------------------------------------
  *		InitPlan
@@ -398,6 +429,10 @@ InitPlan(CmdType operation, Query *parseTree, Plan *plan, EState *estate)
 	rangeTable = parseTree->rtable;
 	resultRelation = parseTree->resultRelation;
 
+#ifndef NO_SECURITY
+	ExecCheckPerms(operation, resultRelation, rangeTable, parseTree);
+#endif
+
 	/******************
 	 *	initialize the node's execution state
 	 ******************
@@ -468,9 +503,32 @@ InitPlan(CmdType operation, Query *parseTree, Plan *plan, EState *estate)
 		estate->es_result_relation_info = NULL;
 	}
 
-#ifndef NO_SECURITY
-	ExecCheckPerms(operation, resultRelation, rangeTable, parseTree);
-#endif
+	/*
+	 * Have to lock relations selected for update
+	 */
+	estate->es_rowMark = NULL;
+	if (parseTree->rowMark != NULL)
+	{
+		Relation		relation;
+		Oid				relid;
+		RowMark		   *rm;
+		List		   *l;
+		execRowMark	   *erm;
+
+		foreach(l, parseTree->rowMark)
+		{
+			rm = lfirst(l);
+			relid = ((RangeTblEntry *)nth(rm->rti - 1, rangeTable))->relid;
+			relation = heap_open(relid);
+			LockRelation(relation, RowShareLock);
+			if (!(rm->info & ROW_MARK_FOR_UPDATE))
+				continue;
+			erm = (execRowMark*) palloc(sizeof(execRowMark));
+			erm->relation = relation;
+			sprintf(erm->resname, "ctid%u", rm->rti);
+			estate->es_rowMark = lappend(estate->es_rowMark, erm);
+		}
+	}
 
 	/******************
 	 *	  initialize the executor "tuple" table.
@@ -777,6 +835,49 @@ ExecutePlan(EState *estate,
 										 * ctid!! */
 				tupleid = &tuple_ctid;
 			}
+			else if (estate->es_rowMark != NULL)
+			{
+				List		   *l;
+				execRowMark	   *erm;
+				Buffer			buffer;
+				HeapTupleData	tuple;
+				int				test;
+
+				foreach (l, estate->es_rowMark)
+				{
+					erm = lfirst(l);
+					if (!ExecGetJunkAttribute(junkfilter,
+											  slot,
+											  erm->resname,
+											  &datum,
+											  &isNull))
+						elog(ERROR, "ExecutePlan: NO (junk) `%s' was found!", erm->resname);
+
+					if (isNull)
+						elog(ERROR, "ExecutePlan: (junk) `%s' is NULL!", erm->resname);
+
+					tuple.t_self = *((ItemPointer) DatumGetPointer(datum));
+					test = heap_mark4update(erm->relation, &tuple, &buffer);
+					ReleaseBuffer(buffer);
+					switch (test)
+					{
+						case HeapTupleSelfUpdated:
+						case HeapTupleMayBeUpdated:
+							break;
+
+						case HeapTupleUpdated:
+							if (XactIsoLevel == XACT_SERIALIZABLE)
+								elog(ERROR, "Can't serialize access due to concurrent update");
+							else
+								elog(ERROR, "Isolation level %u is not supported", XactIsoLevel);
+							return(NULL);
+
+						default:
+							elog(ERROR, "Unknown status %u from heap_mark4update", test);
+							return(NULL);
+					}
+				}
+			}
 
 			/******************
 			 * Finally create a new "clean" tuple with all junk attributes

src/backend/optimizer/plan/planner.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/plan/planner.c,v 1.36 1999/01/18 00:09:47 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/plan/planner.c,v 1.37 1999/01/25 12:01:04 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -20,6 +20,8 @@
 #include "nodes/plannodes.h"
 #include "nodes/parsenodes.h"
 #include "nodes/relation.h"
+#include "nodes/makefuncs.h"
+#include "catalog/pg_type.h"
 #include "parser/parse_expr.h"
 
 #include "utils/elog.h"
@@ -119,6 +121,8 @@ union_planner(Query *parse)
 	else if ((rt_index =
 			  first_inherit_rt_entry(rangetable)) != -1)
 	{
+		if (parse->rowMark != NULL)
+			elog(ERROR, "SELECT FOR UPDATE is not supported for inherit queries");
 		result_plan = (Plan *) plan_inherit_queries(parse, rt_index);
 		/* XXX do we need to do this? bjm 12/19/97 */
 		tlist = preprocess_targetlist(tlist,
@@ -148,17 +152,49 @@ union_planner(Query *parse)
 	   * a new entry and attaches it to the list 'new_tlist' (consisting of the 
 	   * VAR node and the RESDOM node as usual with tlists :-)  ) */
 	  if (parse->hasAggs)
-	    {
+	  {
 	      if (parse->havingQual != NULL)
-		{
-		  new_tlist = check_having_qual_for_vars(parse->havingQual,new_tlist);
-		}
-	    }
+		  {
+		  	new_tlist = check_having_qual_for_vars(parse->havingQual,new_tlist);
+		  }
+	  }
 	  
 	  new_tlist = preprocess_targetlist(new_tlist,
 					    parse->commandType,
 					    parse->resultRelation,
 					    parse->rtable);
+
+	  /* FOR UPDATE ... */
+	  if (parse->rowMark != NULL)
+	  {
+	  	List		   *l;
+		TargetEntry	   *ctid;
+		Resdom		   *resdom;
+		Var			   *var;
+		char		   *resname;
+
+		foreach (l, parse->rowMark)
+		{
+			if (!(((RowMark*)lfirst(l))->info & ROW_MARK_FOR_UPDATE))
+				continue;
+
+			resname = (char*) palloc(32);
+			sprintf(resname, "ctid%u", ((RowMark*)lfirst(l))->rti);
+			resdom = makeResdom(length(new_tlist) + 1,
+								TIDOID,
+								-1,
+								resname,
+								0,
+								0,
+								1);
+
+			var = makeVar(((RowMark*)lfirst(l))->rti, -1, TIDOID, 
+							-1, 0, ((RowMark*)lfirst(l))->rti, -1);
+
+			ctid = makeTargetEntry(resdom, (Node *) var);
+			new_tlist = lappend(new_tlist, ctid);
+		}
+	  }
 	  
 	  /* Here starts the original (pre having) code */
 	  tlist = preprocess_targetlist(tlist,
@@ -290,7 +326,7 @@ union_planner(Query *parse)
 		      pfree(vpm);		
 		  }
 	}		  
-		
+
 	/*
 	 * For now, before we hand back the plan, check to see if there is a
 	 * user-specified sort that needs to be done.  Eventually, this will

src/backend/parser/analyze.c

@@ -5,7 +5,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- *  $Id: analyze.c,v 1.94 1999/01/21 22:48:07 momjian Exp $
+ *  $Id: analyze.c,v 1.95 1999/01/25 12:01:05 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -45,7 +45,8 @@ static Query *transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt);
 static Query *transformCursorStmt(ParseState *pstate, SelectStmt *stmt);
 static Query *transformCreateStmt(ParseState *pstate, CreateStmt *stmt);
 
-static void   transformForUpdate(Query *qry, List *forUpdate);
+static void		transformForUpdate(Query *qry, List *forUpdate);
+void			CheckSelectForUpdate(Query *qry);
 
 List	   *extras_before = NIL;
 List	   *extras_after = NIL;
@@ -1134,6 +1135,19 @@ Node *A_Expr_to_Expr(Node *ptr, bool *intersect_present)
   return result;  
 }
 
+void
+CheckSelectForUpdate(Query *qry)
+{
+	if (qry->unionClause != NULL)
+		elog(ERROR, "SELECT FOR UPDATE is not allowed with UNION/INTERSECT/EXCEPT clause");
+	if (qry->uniqueFlag != NULL)
+		elog(ERROR, "SELECT FOR UPDATE is not allowed with DISTINCT clause");
+	if (qry->groupClause != NULL)
+		elog(ERROR, "SELECT FOR UPDATE is not allowed with GROUP BY clause");
+	if (qry->hasAggs)
+		elog(ERROR, "SELECT FOR UPDATE is not allowed with AGGREGATE");
+}
+
 static void
 transformForUpdate(Query *qry, List *forUpdate)
 {
@@ -1142,6 +1156,8 @@ transformForUpdate(Query *qry, List *forUpdate)
 	List	   *l;
 	Index		i;
 
+	CheckSelectForUpdate(qry);
+
 	if (lfirst(forUpdate) == NULL)		/* all tables */
 	{
 		i = 1;

src/backend/parser/gram.y

@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.48 1999/01/22 19:35:54 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.49 1999/01/25 12:01:13 vadim Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -2798,19 +2798,8 @@ SelectStmt:	  select_w_o_sort sort_clause for_update_clause
 				  first_select->forUpdate = $3;
 				  $$ = (Node *)first_select;
 				}		
-				if (((SelectStmt *)$$)->forUpdate != NULL)
-				{
-					SelectStmt *n = (SelectStmt *)$$;
-
-					if (n->unionClause != NULL)
-						elog(ERROR, "SELECT FOR UPDATE is not allowed with UNION/INTERSECT/EXCEPT clause");
-					if (n->unique != NULL)
-						elog(ERROR, "SELECT FOR UPDATE is not allowed with DISTINCT clause");
-					if (n->groupClause != NULL)
-						elog(ERROR, "SELECT FOR UPDATE is not allowed with GROUP BY clause");
-					if (n->havingClause != NULL)
-						elog(ERROR, "SELECT FOR UPDATE is not allowed with HAVING clause");
-				}
+				if (((SelectStmt *)$$)->forUpdate != NULL && QueryIsRule)
+					elog(ERROR, "SELECT FOR UPDATE is not allowed in RULES");
 			}
 		;
 

src/backend/rewrite/rewriteHandler.c

@@ -6,7 +6,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.30 1999/01/24 00:28:30 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.31 1999/01/25 12:01:14 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1787,6 +1787,7 @@ apply_RIR_view(Node **nodePtr, int rt_index, RangeTblEntry *rte, List *tlist, in
 	}
 }
 
+extern	void CheckSelectForUpdate(Query *rule_action);	/* in analyze.c */
 
 static void
 ApplyRetrieveRule(Query *parsetree,
@@ -1847,6 +1848,7 @@ ApplyRetrieveRule(Query *parsetree,
 		Index		rti = 1;
 		List	   *l2;
 
+		CheckSelectForUpdate(rule_action);
 		/* 
 		 * We believe that rt_index is VIEW - nothing should be
 		 * marked for VIEW, but ACL check must be done.

src/include/nodes/execnodes.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: execnodes.h,v 1.20 1998/12/14 05:19:16 scrappy Exp $
+ * $Id: execnodes.h,v 1.21 1999/01/25 12:01:19 vadim Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -208,6 +208,7 @@ typedef struct EState
 	int		   *es_refcount;
 	uint32		es_processed;	/* # of tuples processed */
 	Oid			es_lastoid;		/* last oid processed (by INSERT) */
+	List	   *es_rowMark;		/* not good place, but there is no other */
 } EState;
 
 /* ----------------