Reimplement the linked list data structure used throughout the backend.

In the past, we used a 'Lispy' linked list implementation: a "list" was
merely a pointer to the head node of the list. The problem with that
design is that it makes lappend() and length() linear time. This patch
fixes that problem (and others) by maintaining a count of the list
length and a pointer to the tail node along with each head node pointer.
A "list" is now a pointer to a structure containing some meta-data
about the list; the head and tail pointers in that structure refer
to ListCell structures that maintain the actual linked list of nodes.

The function names of the list API have also been changed to, I hope,
be more logically consistent. By default, the old function names are
still available; they will be disabled-by-default once the rest of
the tree has been updated to use the new API names.

12 files changed, 146 insertions, 134 deletions

diff --git a/src/backend/utils/adt/name.c b/src/backend/utils/adt/name.c
index 0bd8658b9f3..bb34667c4d3 100644
--- a/src/backend/utils/adt/name.c
+++ b/src/backend/utils/adt/name.c
@@ -14,7 +14,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/name.c,v 1.50 2003/11/29 19:51:59 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/name.c,v 1.51 2004/05/26 04:41:37 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -342,7 +342,8 @@ current_schema(PG_FUNCTION_ARGS)
 
 	if (search_path == NIL)
 		PG_RETURN_NULL();
-	nspname = get_namespace_name(lfirsto(search_path));
+	nspname = get_namespace_name(linitial_oid(search_path));
+	list_free(search_path);
 	if (!nspname)
 		PG_RETURN_NULL();		/* recently-deleted namespace? */
 	PG_RETURN_DATUM(DirectFunctionCall1(namein, CStringGetDatum(nspname)));
@@ -352,25 +353,27 @@ Datum
 current_schemas(PG_FUNCTION_ARGS)
 {
 	List	   *search_path = fetch_search_path(PG_GETARG_BOOL(0));
+	ListCell   *l;
 	Datum	   *names;
 	int			i;
 	ArrayType  *array;
 
 	/* +1 here is just to avoid palloc(0) error */
+
 	names = (Datum *) palloc((length(search_path) + 1) * sizeof(Datum));
 	i = 0;
-	while (search_path)
+	foreach(l, search_path)
 	{
 		char	   *nspname;
 
-		nspname = get_namespace_name(lfirsto(search_path));
+		nspname = get_namespace_name(lfirst_oid(l));
 		if (nspname)			/* watch out for deleted namespace */
 		{
 			names[i] = DirectFunctionCall1(namein, CStringGetDatum(nspname));
 			i++;
 		}
-		search_path = lnext(search_path);
 	}
+	list_free(search_path);
 
 	array = construct_array(names, i,
 							NAMEOID,
diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
index fe2e7aa6cf8..9c688401ece 100644
--- a/src/backend/utils/adt/regproc.c
+++ b/src/backend/utils/adt/regproc.c
@@ -13,7 +13,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/regproc.c,v 1.87 2004/05/07 00:24:58 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/regproc.c,v 1.88 2004/05/26 04:41:37 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1099,7 +1099,7 @@ stringToQualifiedNameList(const char *string, const char *caller)
 	char	   *rawname;
 	List	   *result = NIL;
 	List	   *namelist;
-	List	   *l;
+	ListCell   *l;
 
 	/* We need a modifiable copy of the input string. */
 	rawname = pstrdup(string);
diff --git a/src/backend/utils/adt/ri_triggers.c b/src/backend/utils/adt/ri_triggers.c
index 47384fbb89f..9e3a06cd822 100644
--- a/src/backend/utils/adt/ri_triggers.c
+++ b/src/backend/utils/adt/ri_triggers.c
@@ -17,7 +17,7 @@
  *
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/backend/utils/adt/ri_triggers.c,v 1.67 2004/02/03 17:34:03 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/ri_triggers.c,v 1.68 2004/05/26 04:41:38 neilc Exp $
  *
  * ----------
  */
@@ -2571,8 +2571,8 @@ RI_Initial_Check(FkConstraint *fkconstraint, Relation rel, Relation pkrel)
 	char		attname[MAX_QUOTED_NAME_LEN];
 	char		fkattname[MAX_QUOTED_NAME_LEN];
 	const char *sep;
-	List		*list;
-	List		*list2;
+	ListCell	*l;
+	ListCell	*l2;
 	int			old_work_mem;
 	char		workmembuf[32];
 	int			spi_result;
@@ -2605,9 +2605,9 @@ RI_Initial_Check(FkConstraint *fkconstraint, Relation rel, Relation pkrel)
 
 	sprintf(querystr, "SELECT ");
 	sep="";
-	foreach(list, fkconstraint->fk_attrs)
+	foreach(l, fkconstraint->fk_attrs)
 	{
-		quoteOneName(attname, strVal(lfirst(list)));
+		quoteOneName(attname, strVal(lfirst(l)));
 		snprintf(querystr + strlen(querystr), sizeof(querystr) - strlen(querystr),
 				 "%sfk.%s", sep, attname);
 		sep = ", ";
@@ -2620,12 +2620,10 @@ RI_Initial_Check(FkConstraint *fkconstraint, Relation rel, Relation pkrel)
 			 relname, pkrelname);
 
 	sep="";
-	for (list=fkconstraint->pk_attrs, list2=fkconstraint->fk_attrs; 
-		 list != NIL && list2 != NIL; 
-		 list=lnext(list), list2=lnext(list2))
+	forboth(l, fkconstraint->pk_attrs, l2, fkconstraint->fk_attrs)
 	{
-		quoteOneName(attname, strVal(lfirst(list)));
-		quoteOneName(fkattname, strVal(lfirst(list2)));
+		quoteOneName(attname, strVal(lfirst(l)));
+		quoteOneName(fkattname, strVal(lfirst(l2)));
 		snprintf(querystr + strlen(querystr), sizeof(querystr) - strlen(querystr),
 				 "%spk.%s=fk.%s",
 				 sep, attname, fkattname);
@@ -2635,14 +2633,14 @@ RI_Initial_Check(FkConstraint *fkconstraint, Relation rel, Relation pkrel)
 	 * It's sufficient to test any one pk attribute for null to detect a
 	 * join failure.
 	 */
-	quoteOneName(attname, strVal(lfirst(fkconstraint->pk_attrs)));
+	quoteOneName(attname, strVal(linitial(fkconstraint->pk_attrs)));
 	snprintf(querystr + strlen(querystr), sizeof(querystr) - strlen(querystr),
 			 ") WHERE pk.%s IS NULL AND (", attname);
 
 	sep="";
-	foreach(list, fkconstraint->fk_attrs)
+	foreach(l, fkconstraint->fk_attrs)
 	{
-		quoteOneName(attname, strVal(lfirst(list)));
+		quoteOneName(attname, strVal(lfirst(l)));
 		snprintf(querystr + strlen(querystr), sizeof(querystr) - strlen(querystr),
 				 "%sfk.%s IS NOT NULL",
 				 sep, attname);
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 95e457c261f..213dc61202b 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -3,7 +3,7 @@
  *				back to source text
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.166 2004/05/10 22:44:46 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.167 2004/05/26 04:41:38 neilc Exp $
  *
  *	  This software is copyrighted by Jan Wieck - Hamburg.
  *
@@ -627,6 +627,7 @@ pg_get_indexdef_worker(Oid indexrelid, int colno, int prettyFlags)
 	Form_pg_class idxrelrec;
 	Form_pg_am	amrec;
 	List	   *indexprs;
+	ListCell   *indexpr_item;
 	List	   *context;
 	Oid			indrelid;
 	int			keyno;
@@ -691,6 +692,8 @@ pg_get_indexdef_worker(Oid indexrelid, int colno, int prettyFlags)
 	else
 		indexprs = NIL;
 
+	indexpr_item = list_head(indexprs);
+
 	context = deparse_context_for(get_rel_name(indrelid), indrelid);
 
 	/*
@@ -733,10 +736,10 @@ pg_get_indexdef_worker(Oid indexrelid, int colno, int prettyFlags)
 			/* expressional index */
 			Node	   *indexkey;
 
-			if (indexprs == NIL)
+			if (indexpr_item == NULL)
 				elog(ERROR, "too few entries in indexprs list");
-			indexkey = (Node *) lfirst(indexprs);
-			indexprs = lnext(indexprs);
+			indexkey = (Node *) lfirst(indexpr_item);
+			indexpr_item = lnext(indexpr_item);
 			/* Deparse */
 			str = deparse_expression_pretty(indexkey, context, false, false,
 											prettyFlags, 0);
@@ -1358,7 +1361,7 @@ deparse_context_for_subplan(const char *name, List *tlist,
 	List	   *attrs = NIL;
 	int			nattrs = 0;
 	int			rtablelength = length(rtable);
-	List	   *tl;
+	ListCell   *tl;
 	char		buf[32];
 
 	foreach(tl, tlist)
@@ -1526,7 +1529,7 @@ make_ruledef(StringInfo buf, HeapTuple ruletup, TupleDesc rulettc,
 		 * (which can only be references to OLD and NEW).  Use the rtable
 		 * of the first query in the action list for this purpose.
 		 */
-		query = (Query *) lfirst(actions);
+		query = (Query *) linitial(actions);
 
 		/*
 		 * If the action is INSERT...SELECT, OLD/NEW have been pushed down
@@ -1556,7 +1559,7 @@ make_ruledef(StringInfo buf, HeapTuple ruletup, TupleDesc rulettc,
 	/* Finally the rules actions */
 	if (length(actions) > 1)
 	{
-		List	   *action;
+		ListCell   *action;
 		Query	   *query;
 
 		appendStringInfo(buf, "(");
@@ -1579,7 +1582,7 @@ make_ruledef(StringInfo buf, HeapTuple ruletup, TupleDesc rulettc,
 	{
 		Query	   *query;
 
-		query = (Query *) lfirst(actions);
+		query = (Query *) linitial(actions);
 		get_query_def(query, buf, NIL, NULL, prettyFlags, 0);
 		appendStringInfo(buf, ";");
 	}
@@ -1636,7 +1639,7 @@ make_viewdef(StringInfo buf, HeapTuple ruletup, TupleDesc rulettc,
 		return;
 	}
 
-	query = (Query *) lfirst(actions);
+	query = (Query *) linitial(actions);
 
 	if (ev_type != '1' || ev_attr >= 0 || !is_instead ||
 		strcmp(ev_qual, "<>") != 0 || query->commandType != CMD_SELECT)
@@ -1670,7 +1673,7 @@ get_query_def(Query *query, StringInfo buf, List *parentnamespace,
 	deparse_namespace dpns;
 
 	context.buf = buf;
-	context.namespaces = lcons(&dpns, parentnamespace);
+	context.namespaces = lcons(&dpns, list_copy(parentnamespace));
 	context.varprefix = (parentnamespace != NIL ||
 						 length(query->rtable) != 1);
 	context.prettyFlags = prettyFlags;
@@ -1725,7 +1728,7 @@ get_select_query_def(Query *query, deparse_context *context,
 	StringInfo	buf = context->buf;
 	bool		force_colno;
 	char	   *sep;
-	List	   *l;
+	ListCell   *l;
 
 	/*
 	 * If the Query node has a setOperations tree, then it's the top level
@@ -1802,7 +1805,7 @@ get_basic_select_query(Query *query, deparse_context *context,
 {
 	StringInfo	buf = context->buf;
 	char	   *sep;
-	List	   *l;
+	ListCell   *l;
 	int			colno;
 
 	/*
@@ -2057,7 +2060,7 @@ get_insert_query_def(Query *query, deparse_context *context)
 	RangeTblEntry *select_rte = NULL;
 	RangeTblEntry *rte;
 	char	   *sep;
-	List	   *l;
+	ListCell   *l;
 
 	/*
 	 * If it's an INSERT ... SELECT there will be a single subquery RTE
@@ -2136,10 +2139,10 @@ get_insert_query_def(Query *query, deparse_context *context)
 static void
 get_update_query_def(Query *query, deparse_context *context)
 {
-	StringInfo	buf = context->buf;
-	char	   *sep;
-	RangeTblEntry *rte;
-	List	   *l;
+	StringInfo		 buf = context->buf;
+	char			*sep;
+	RangeTblEntry	*rte;
+	ListCell		*l;
 
 	/*
 	 * Start the query with UPDATE relname SET
@@ -2271,17 +2274,17 @@ static void
 get_names_for_var(Var *var, deparse_context *context,
 				  char **schemaname, char **refname, char **attname)
 {
-	List	   *nslist = context->namespaces;
+	ListCell   *nslist_item = list_head(context->namespaces);
 	int			sup = var->varlevelsup;
 	deparse_namespace *dpns;
 	RangeTblEntry *rte;
 
 	/* Find appropriate nesting depth */
-	while (sup-- > 0 && nslist != NIL)
-		nslist = lnext(nslist);
-	if (nslist == NIL)
+	while (sup-- > 0 && nslist_item != NULL)
+		nslist_item = lnext(nslist_item);
+	if (nslist_item == NULL)
 		elog(ERROR, "bogus varlevelsup: %d", var->varlevelsup);
-	dpns = (deparse_namespace *) lfirst(nslist);
+	dpns = (deparse_namespace *) lfirst(nslist_item);
 
 	/* Find the relevant RTE */
 	if (var->varno >= 1 && var->varno <= length(dpns->rtable))
@@ -2342,13 +2345,13 @@ get_names_for_var(Var *var, deparse_context *context,
 static RangeTblEntry *
 find_rte_by_refname(const char *refname, deparse_context *context)
 {
-	RangeTblEntry *result = NULL;
-	List	   *nslist;
+	RangeTblEntry  *result = NULL;
+	ListCell	   *nslist;
 
 	foreach(nslist, context->namespaces)
 	{
 		deparse_namespace *dpns = (deparse_namespace *) lfirst(nslist);
-		List	   *rtlist;
+		ListCell	   *rtlist;
 
 		foreach(rtlist, dpns->rtable)
 		{
@@ -2396,7 +2399,7 @@ get_simple_binary_op_name(OpExpr *expr)
 	if (length(args) == 2)
 	{
 		/* binary operator */
-		Node	   *arg1 = (Node *) lfirst(args);
+		Node	   *arg1 = (Node *) linitial(args);
 		Node	   *arg2 = (Node *) lsecond(args);
 		const char *op;
 
@@ -2501,7 +2504,7 @@ isSimpleNode(Node *node, Node *parentNode, int prettyFlags)
 					 * Operators are same priority --- can skip parens
 					 * only if we have (a - b) - c, not a - (b - c).
 					 */
-					if (node == (Node *) lfirst(((OpExpr *) parentNode)->args))
+					if (node == (Node *) linitial(((OpExpr *) parentNode)->args))
 						return true;
 
 					return false;
@@ -2759,8 +2762,8 @@ get_rule_expr(Node *node, deparse_context *context,
 				ArrayRef   *aref = (ArrayRef *) node;
 				bool		savevarprefix = context->varprefix;
 				bool		need_parens;
-				List	   *lowlist;
-				List	   *uplist;
+				ListCell   *lowlist_item;
+				ListCell   *uplist_item;
 
 				/*
 				 * If we are doing UPDATE array[n] = expr, we need to
@@ -2783,18 +2786,19 @@ get_rule_expr(Node *node, deparse_context *context,
 				if (need_parens)
 					appendStringInfoChar(buf, ')');
 				context->varprefix = savevarprefix;
-				lowlist = aref->reflowerindexpr;
-				foreach(uplist, aref->refupperindexpr)
+				lowlist_item = list_head(aref->reflowerindexpr);
+				foreach(uplist_item, aref->refupperindexpr)
 				{
 					appendStringInfo(buf, "[");
-					if (lowlist)
+					if (lowlist_item)
 					{
-						get_rule_expr((Node *) lfirst(lowlist), context,
+						get_rule_expr((Node *) lfirst(lowlist_item), context,
 									  false);
 						appendStringInfo(buf, ":");
-						lowlist = lnext(lowlist);
+						lowlist_item = lnext(lowlist_item);
 					}
-					get_rule_expr((Node *) lfirst(uplist), context, false);
+					get_rule_expr((Node *) lfirst(uplist_item),
+								  context, false);
 					appendStringInfo(buf, "]");
 				}
 				if (aref->refassgnexpr)
@@ -2818,7 +2822,7 @@ get_rule_expr(Node *node, deparse_context *context,
 			{
 				DistinctExpr *expr = (DistinctExpr *) node;
 				List	   *args = expr->args;
-				Node	   *arg1 = (Node *) lfirst(args);
+				Node	   *arg1 = (Node *) linitial(args);
 				Node	   *arg2 = (Node *) lsecond(args);
 
 				if (!PRETTY_PAREN(context))
@@ -2835,7 +2839,7 @@ get_rule_expr(Node *node, deparse_context *context,
 			{
 				ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
 				List	   *args = expr->args;
-				Node	   *arg1 = (Node *) lfirst(args);
+				Node	   *arg1 = (Node *) linitial(args);
 				Node	   *arg2 = (Node *) lsecond(args);
 
 				if (!PRETTY_PAREN(context))
@@ -2856,20 +2860,22 @@ get_rule_expr(Node *node, deparse_context *context,
 		case T_BoolExpr:
 			{
 				BoolExpr   *expr = (BoolExpr *) node;
-				List	   *args = expr->args;
+				Node	   *first_arg = linitial(expr->args);
+				ListCell   *arg = lnext(list_head(expr->args));
 
 				switch (expr->boolop)
 				{
 					case AND_EXPR:
 						if (!PRETTY_PAREN(context))
 							appendStringInfoChar(buf, '(');
-						get_rule_expr_paren((Node *) lfirst(args), context,
+						get_rule_expr_paren(first_arg, context,
 											false, node);
-						while ((args = lnext(args)) != NIL)
+						while (arg)
 						{
 							appendStringInfo(buf, " AND ");
-							get_rule_expr_paren((Node *) lfirst(args), context,
+							get_rule_expr_paren((Node *) lfirst(arg), context,
 												false, node);
+							arg = lnext(arg);
 						}
 						if (!PRETTY_PAREN(context))
 							appendStringInfoChar(buf, ')');
@@ -2878,13 +2884,14 @@ get_rule_expr(Node *node, deparse_context *context,
 					case OR_EXPR:
 						if (!PRETTY_PAREN(context))
 							appendStringInfoChar(buf, '(');
-						get_rule_expr_paren((Node *) lfirst(args), context,
+						get_rule_expr_paren(first_arg, context,
 											false, node);
-						while ((args = lnext(args)) != NIL)
+						while (arg)
 						{
 							appendStringInfo(buf, " OR ");
-							get_rule_expr_paren((Node *) lfirst(args), context,
+							get_rule_expr_paren((Node *) lfirst(arg), context,
 												false, node);
+							arg = lnext(arg);
 						}
 						if (!PRETTY_PAREN(context))
 							appendStringInfoChar(buf, ')');
@@ -2894,7 +2901,7 @@ get_rule_expr(Node *node, deparse_context *context,
 						if (!PRETTY_PAREN(context))
 							appendStringInfoChar(buf, '(');
 						appendStringInfo(buf, "NOT ");
-						get_rule_expr_paren((Node *) lfirst(args), context,
+						get_rule_expr_paren(first_arg, context,
 											false, node);
 						if (!PRETTY_PAREN(context))
 							appendStringInfoChar(buf, ')');
@@ -2989,7 +2996,7 @@ get_rule_expr(Node *node, deparse_context *context,
 		case T_CaseExpr:
 			{
 				CaseExpr   *caseexpr = (CaseExpr *) node;
-				List	   *temp;
+				ListCell   *temp;
 
 				appendContextKeyword(context, "CASE",
 									 0, PRETTYINDENT_VAR, 0);
@@ -3035,7 +3042,7 @@ get_rule_expr(Node *node, deparse_context *context,
 		case T_ArrayExpr:
 			{
 				ArrayExpr  *arrayexpr = (ArrayExpr *) node;
-				List	   *element;
+				ListCell   *element;
 				char	   *sep;
 
 				appendStringInfo(buf, "ARRAY[");
@@ -3055,7 +3062,7 @@ get_rule_expr(Node *node, deparse_context *context,
 		case T_RowExpr:
 			{
 				RowExpr	   *rowexpr = (RowExpr *) node;
-				List	   *arg;
+				ListCell   *arg;
 				char	   *sep;
 
 				/*
@@ -3082,7 +3089,7 @@ get_rule_expr(Node *node, deparse_context *context,
 		case T_CoalesceExpr:
 			{
 				CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;
-				List	   *arg;
+				ListCell   *arg;
 				char	   *sep;
 
 				appendStringInfo(buf, "COALESCE(");
@@ -3102,7 +3109,7 @@ get_rule_expr(Node *node, deparse_context *context,
 		case T_NullIfExpr:
 			{
 				NullIfExpr *nullifexpr = (NullIfExpr *) node;
-				List	   *arg;
+				ListCell   *arg;
 				char	   *sep;
 
 				appendStringInfo(buf, "NULLIF(");
@@ -3239,7 +3246,7 @@ get_oper_expr(OpExpr *expr, deparse_context *context)
 	if (length(args) == 2)
 	{
 		/* binary operator */
-		Node	   *arg1 = (Node *) lfirst(args);
+		Node	   *arg1 = (Node *) linitial(args);
 		Node	   *arg2 = (Node *) lsecond(args);
 
 		get_rule_expr_paren(arg1, context, true, (Node *) expr);
@@ -3252,7 +3259,7 @@ get_oper_expr(OpExpr *expr, deparse_context *context)
 	else
 	{
 		/* unary operator --- but which side? */
-		Node	   *arg = (Node *) lfirst(args);
+		Node	   *arg = (Node *) linitial(args);
 		HeapTuple	tp;
 		Form_pg_operator optup;
 
@@ -3298,7 +3305,7 @@ get_func_expr(FuncExpr *expr, deparse_context *context,
 	Oid			funcoid = expr->funcid;
 	Oid			argtypes[FUNC_MAX_ARGS];
 	int			nargs;
-	List	   *l;
+	ListCell   *l;
 	char	   *sep;
 
 	/*
@@ -3308,7 +3315,7 @@ get_func_expr(FuncExpr *expr, deparse_context *context,
 	 */
 	if (expr->funcformat == COERCE_IMPLICIT_CAST && !showimplicit)
 	{
-		get_rule_expr_paren((Node *) lfirst(expr->args), context,
+		get_rule_expr_paren((Node *) linitial(expr->args), context,
 							showimplicit, (Node *) expr);
 		return;
 	}
@@ -3320,7 +3327,7 @@ get_func_expr(FuncExpr *expr, deparse_context *context,
 	if (expr->funcformat == COERCE_EXPLICIT_CAST ||
 		expr->funcformat == COERCE_IMPLICIT_CAST)
 	{
-		Node	   *arg = lfirst(expr->args);
+		Node	   *arg = linitial(expr->args);
 		Oid			rettype = expr->funcresulttype;
 		int32		coercedTypmod;
 
@@ -3424,7 +3431,7 @@ strip_type_coercion(Node *expr, Oid resultType)
 		if (exprIsLengthCoercion(expr, NULL))
 			return expr;
 
-		return (Node *) lfirst(func->args);
+		return (Node *) linitial(func->args);
 	}
 
 	return expr;
@@ -3580,7 +3587,7 @@ get_sublink_expr(SubLink *sublink, deparse_context *context)
 {
 	StringInfo	buf = context->buf;
 	Query	   *query = (Query *) (sublink->subselect);
-	List	   *l;
+	ListCell   *l;
 	char	   *sep;
 	bool		need_paren;
 
@@ -3625,7 +3632,7 @@ get_sublink_expr(SubLink *sublink, deparse_context *context)
 
 		case ANY_SUBLINK:
 			if (length(sublink->operName) == 1 &&
-				strcmp(strVal(lfirst(sublink->operName)), "=") == 0)
+				strcmp(strVal(linitial(sublink->operName)), "=") == 0)
 			{
 				/* Represent = ANY as IN */
 				appendStringInfo(buf, "IN ");
@@ -3680,7 +3687,7 @@ get_from_clause(Query *query, deparse_context *context)
 {
 	StringInfo	buf = context->buf;
 	bool		first = true;
-	List	   *l;
+	ListCell   *l;
 
 	/*
 	 * We use the query's jointree as a guide to what to print.  However,
@@ -3763,12 +3770,12 @@ get_from_clause_item(Node *jtnode, Query *query, deparse_context *context)
 			gavealias = true;
 			if (rte->alias->colnames != NIL && coldeflist == NIL)
 			{
-				List	   *col;
+				ListCell   *col;
 
 				appendStringInfoChar(buf, '(');
 				foreach(col, rte->alias->colnames)
 				{
-					if (col != rte->alias->colnames)
+					if (col != list_head(rte->alias->colnames))
 						appendStringInfo(buf, ", ");
 					appendStringInfoString(buf,
 										   quote_identifier(strVal(lfirst(col))));
@@ -3897,12 +3904,12 @@ get_from_clause_item(Node *jtnode, Query *query, deparse_context *context)
 		{
 			if (j->using)
 			{
-				List	   *col;
+				ListCell   *col;
 
 				appendStringInfo(buf, " USING (");
 				foreach(col, j->using)
 				{
-					if (col != j->using)
+					if (col != list_head(j->using))
 						appendStringInfo(buf, ", ");
 					appendStringInfoString(buf,
 								quote_identifier(strVal(lfirst(col))));
@@ -3929,12 +3936,12 @@ get_from_clause_item(Node *jtnode, Query *query, deparse_context *context)
 							 quote_identifier(j->alias->aliasname));
 			if (j->alias->colnames != NIL)
 			{
-				List	   *col;
+				ListCell   *col;
 
 				appendStringInfoChar(buf, '(');
 				foreach(col, j->alias->colnames)
 				{
-					if (col != j->alias->colnames)
+					if (col != list_head(j->alias->colnames))
 						appendStringInfo(buf, ", ");
 					appendStringInfoString(buf,
 								  quote_identifier(strVal(lfirst(col))));
@@ -3958,7 +3965,7 @@ static void
 get_from_clause_coldeflist(List *coldeflist, deparse_context *context)
 {
 	StringInfo	buf = context->buf;
-	List	   *col;
+	ListCell   *col;
 	int			i = 0;
 
 	appendStringInfoChar(buf, '(');
@@ -4337,20 +4344,21 @@ generate_operator_name(Oid operid, Oid arg1, Oid arg2)
 static void
 print_operator_name(StringInfo buf, List *opname)
 {
-	int			nnames = length(opname);
+	ListCell	*op = list_head(opname);
+	int			 nnames = length(opname);
 
 	if (nnames == 1)
-		appendStringInfoString(buf, strVal(lfirst(opname)));
+		appendStringInfoString(buf, strVal(lfirst(op)));
 	else
 	{
 		appendStringInfo(buf, "OPERATOR(");
 		while (nnames-- > 1)
 		{
 			appendStringInfo(buf, "%s.",
-							 quote_identifier(strVal(lfirst(opname))));
-			opname = lnext(opname);
+							 quote_identifier(strVal(lfirst(op))));
+			op = lnext(op);
 		}
-		appendStringInfo(buf, "%s)", strVal(lfirst(opname)));
+		appendStringInfo(buf, "%s)", strVal(lfirst(op)));
 	}
 }
 
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c
index ded7260c784..cd9a6444d41 100644
--- a/src/backend/utils/adt/selfuncs.c
+++ b/src/backend/utils/adt/selfuncs.c
@@ -15,7 +15,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.158 2004/02/27 21:44:34 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.159 2004/05/26 04:41:39 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1936,7 +1936,7 @@ estimate_num_groups(Query *root, List *groupExprs, double input_rows)
 	List	   *allvars = NIL;
 	List	   *varinfos = NIL;
 	double		numdistinct;
-	List	   *l;
+	ListCell   *l;
 	typedef struct
 	{							/* varinfos is a List of these */
 		Var		   *var;
@@ -1987,14 +1987,14 @@ estimate_num_groups(Query *root, List *groupExprs, double input_rows)
 		VariableStatData vardata;
 		double		ndistinct;
 		bool		keep = true;
-		List	   *l2;
+		ListCell   *l2;
 
 		examine_variable(root, (Node *) var, 0, &vardata);
 		ndistinct = get_variable_numdistinct(&vardata);
 		ReleaseVariableStats(vardata);
 
 		/* cannot use foreach here because of possible lremove */
-		l2 = varinfos;
+		l2 = list_head(varinfos);
 		while (l2)
 		{
 			MyVarInfo  *varinfo = (MyVarInfo *) lfirst(l2);
@@ -2043,7 +2043,7 @@ estimate_num_groups(Query *root, List *groupExprs, double input_rows)
 
 	do
 	{
-		MyVarInfo  *varinfo1 = (MyVarInfo *) lfirst(varinfos);
+		MyVarInfo  *varinfo1 = (MyVarInfo *) linitial(varinfos);
 		RelOptInfo *rel = find_base_rel(root, varinfo1->var->varno);
 		double		reldistinct = varinfo1->ndistinct;
 		List	   *newvarinfos = NIL;
@@ -2052,7 +2052,7 @@ estimate_num_groups(Query *root, List *groupExprs, double input_rows)
 		 * Get the largest numdistinct estimate of the Vars for this rel.
 		 * Also, construct new varinfos list of remaining Vars.
 		 */
-		foreach(l, lnext(varinfos))
+		for_each_cell(l, lnext(list_head(varinfos)))
 		{
 			MyVarInfo  *varinfo2 = (MyVarInfo *) lfirst(l);
 
@@ -2844,7 +2844,7 @@ get_restriction_variable(Query *root, List *args, int varRelid,
 	if (length(args) != 2)
 		return false;
 
-	left = (Node *) lfirst(args);
+	left = (Node *) linitial(args);
 	right = (Node *) lsecond(args);
 
 	/*
@@ -2895,7 +2895,7 @@ get_join_variables(Query *root, List *args,
 	if (length(args) != 2)
 		elog(ERROR, "join operator should take two arguments");
 
-	left = (Node *) lfirst(args);
+	left = (Node *) linitial(args);
 	right = (Node *) lsecond(args);
 
 	examine_variable(root, left, 0, vardata1);
@@ -3033,16 +3033,16 @@ examine_variable(Query *root, Node *node, int varRelid,
 		 * different index opclasses; if so, we need to pick one that
 		 * matches the operator we are estimating for.  FIXME later.
 		 */
-		List	   *ilist;
+		ListCell   *ilist;
 
 		foreach(ilist, onerel->indexlist)
 		{
 			IndexOptInfo *index = (IndexOptInfo *) lfirst(ilist);
-			List	   *indexprs;
+			ListCell   *indexpr_item;
 			int			pos;
 
-			indexprs = index->indexprs;
-			if (indexprs == NIL)
+			indexpr_item = list_head(index->indexprs);
+			if (indexpr_item == NULL)
 				continue;		/* no expressions here... */
 
 			/*
@@ -3058,9 +3058,9 @@ examine_variable(Query *root, Node *node, int varRelid,
 				{
 					Node	   *indexkey;
 
-					if (indexprs == NIL)
+					if (indexpr_item == NULL)
 						elog(ERROR, "too few entries in indexprs list");
-					indexkey = (Node *) lfirst(indexprs);
+					indexkey = (Node *) lfirst(indexpr_item);
 					if (indexkey && IsA(indexkey, RelabelType))
 						indexkey = (Node *) ((RelabelType *) indexkey)->arg;
 					if (equal(node, indexkey))
@@ -3081,7 +3081,7 @@ examine_variable(Query *root, Node *node, int varRelid,
 						if (vardata->statsTuple)
 							break;
 					}
-					indexprs = lnext(indexprs);
+					indexpr_item = lnext(indexpr_item);
 				}
 			}
 			if (vardata->statsTuple)
diff --git a/src/backend/utils/adt/tid.c b/src/backend/utils/adt/tid.c
index 8433bc98c4d..f8f207d72ab 100644
--- a/src/backend/utils/adt/tid.c
+++ b/src/backend/utils/adt/tid.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/tid.c,v 1.43 2004/05/07 00:24:58 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/tid.c,v 1.44 2004/05/26 04:41:39 neilc Exp $
  *
  * NOTES
  *	  input routine largely stolen from boxin().
@@ -241,7 +241,7 @@ currtid_for_view(Relation viewrel, ItemPointer tid)
 
 			if (length(rewrite->actions) != 1)
 				elog(ERROR, "only one select rule is allowed in views");
-			query = (Query *) lfirst(rewrite->actions);
+			query = (Query *) linitial(rewrite->actions);
 			tle = get_tle_by_resno(query->targetList, tididx+1);
 			if (tle && tle->expr && IsA(tle->expr, Var))
 			{
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index f329486321d..410faad6925 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/varlena.c,v 1.112 2004/02/21 00:34:53 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/varlena.c,v 1.113 2004/05/26 04:41:39 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1623,7 +1623,7 @@ textToQualifiedNameList(text *textval, const char *caller)
 	char	   *rawname;
 	List	   *result = NIL;
 	List	   *namelist;
-	List	   *l;
+	ListCell   *l;
 
 	/* Convert to C string (handles possible detoasting). */
 	/* Note we rely on being able to modify rawname below. */
diff --git a/src/backend/utils/cache/catcache.c b/src/backend/utils/cache/catcache.c
index 5732e5ab424..5e91a7283ec 100644
--- a/src/backend/utils/cache/catcache.c
+++ b/src/backend/utils/cache/catcache.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/catcache.c,v 1.111 2003/11/29 19:52:00 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/catcache.c,v 1.112 2004/05/26 04:41:40 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1317,6 +1317,7 @@ SearchCatCacheList(CatCache *cache,
 	CatCList   *cl;
 	CatCTup    *ct;
 	List	   *ctlist;
+	ListCell   *ctlist_item;
 	int			nmembers;
 	Relation	relation;
 	SysScanDesc scandesc;
@@ -1510,15 +1511,16 @@ SearchCatCacheList(CatCache *cache,
 	cl->hash_value = lHashValue;
 	cl->n_members = nmembers;
 	/* The list is backwards because we built it with lcons */
+	ctlist_item = list_head(ctlist);
 	for (i = nmembers; --i >= 0;)
 	{
-		cl->members[i] = ct = (CatCTup *) lfirst(ctlist);
+		cl->members[i] = ct = (CatCTup *) lfirst(ctlist_item);
 		Assert(ct->c_list == NULL);
 		ct->c_list = cl;
 		/* mark list dead if any members already dead */
 		if (ct->dead)
 			cl->dead = true;
-		ctlist = lnext(ctlist);
+		ctlist_item = lnext(ctlist_item);
 	}
 
 	DLAddHead(&cache->cc_lists, &cl->cache_elem);
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index 0e4a31745fd..4d8190a7b0f 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.202 2004/05/08 19:09:25 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.203 2004/05/26 04:41:40 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1872,7 +1872,7 @@ RelationCacheInvalidate(void)
 	Relation	relation;
 	List	   *rebuildFirstList = NIL;
 	List	   *rebuildList = NIL;
-	List	   *l;
+	ListCell   *l;
 
 	/* Phase 1 */
 	hash_seq_init(&status, RelationIdCache);
@@ -2577,23 +2577,24 @@ RelationGetIndexList(Relation relation)
 static List *
 insert_ordered_oid(List *list, Oid datum)
 {
-	List	   *l;
+	ListCell *prev;
 
 	/* Does the datum belong at the front? */
-	if (list == NIL || datum < lfirsto(list))
-		return lconso(datum, list);
+	if (list == NIL || datum < linitial_oid(list))
+		return lcons_oid(datum, list);
 	/* No, so find the entry it belongs after */
-	l = list;
+	prev = list_head(list);
 	for (;;)
 	{
-		List	   *n = lnext(l);
+		ListCell *curr = lnext(prev);
 
-		if (n == NIL || datum < lfirsto(n))
-			break;				/* it belongs before n */
-		l = n;
+		if (curr == NULL || datum < lfirst_oid(curr))
+			break;		/* it belongs after 'prev', before 'curr' */
+
+		prev = curr;
 	}
-	/* Insert datum into list after item l */
-	lnext(l) = lconso(datum, lnext(l));
+	/* Insert datum into list after 'prev' */
+	lappend_cell_oid(list, prev, datum);
 	return list;
 }
 
diff --git a/src/backend/utils/cache/typcache.c b/src/backend/utils/cache/typcache.c
index 7a8e67c83c8..b3ef61c2d72 100644
--- a/src/backend/utils/cache/typcache.c
+++ b/src/backend/utils/cache/typcache.c
@@ -36,7 +36,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/typcache.c,v 1.5 2004/04/01 21:28:45 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/typcache.c,v 1.6 2004/05/26 04:41:40 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -432,7 +432,7 @@ assign_record_type_typmod(TupleDesc tupDesc)
 	Oid			hashkey[REC_HASH_KEYS];
 	bool		found;
 	int			i;
-	List	   *l;
+	ListCell   *l;
 	int32		newtypmod;
 	MemoryContext oldcxt;
 
diff --git a/src/backend/utils/init/miscinit.c b/src/backend/utils/init/miscinit.c
index 75cc07a518d..6507891d66d 100644
--- a/src/backend/utils/init/miscinit.c
+++ b/src/backend/utils/init/miscinit.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/init/miscinit.c,v 1.124 2004/04/19 17:42:58 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/init/miscinit.c,v 1.125 2004/05/26 04:41:43 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -883,7 +883,7 @@ process_preload_libraries(char *preload_libraries_string)
 {
 	char	   *rawstring;
 	List	   *elemlist;
-	List	   *l;
+	ListCell   *l;
 
 	if (preload_libraries_string == NULL)
 		return;
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 8a51e8aa049..1cfc3e0346b 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -10,7 +10,7 @@
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.206 2004/05/21 05:08:03 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.207 2004/05/26 04:41:43 neilc Exp $
  *
  *--------------------------------------------------------------------
  */
@@ -3290,7 +3290,7 @@ flatten_set_variable_args(const char *name, List *args)
 	struct config_generic *record;
 	int			flags;
 	StringInfoData buf;
-	List	   *l;
+	ListCell   *l;
 
 	/*
 	 * Fast path if just DEFAULT.  We do not check the variable name in
@@ -3310,7 +3310,7 @@ flatten_set_variable_args(const char *name, List *args)
 
 	/* Complain if list input and non-list variable */
 	if ((flags & GUC_LIST_INPUT) == 0 &&
-		lnext(args) != NIL)
+		list_length(args) != 1)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("SET %s takes only one argument", name)));
@@ -3322,7 +3322,7 @@ flatten_set_variable_args(const char *name, List *args)
 		A_Const    *arg = (A_Const *) lfirst(l);
 		char	   *val;
 
-		if (l != args)
+		if (l != list_head(args))
 			appendStringInfo(&buf, ", ");
 
 		if (!IsA(arg, A_Const))
@@ -4430,7 +4430,7 @@ assign_log_destination(const char *value, bool doit, GucSource source)
 {
 	char *rawstring;
 	List *elemlist;
-	List *l;
+	ListCell *l;
 	unsigned int  newlogdest = 0;
  
 	/* Need a modifiable copy of string */