Replace max_expr_depth parameter with a max_stack_depth parameter that

is measured in kilobytes and checked against actual physical execution
stack depth, as per my proposal of 30-Dec.  This gives us a fairly
bulletproof defense against crashing due to runaway recursive functions.

4 files changed, 17 insertions, 14 deletions

diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index f34ebb0986..4aba00bb71 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -1,18 +1,19 @@
 /*-------------------------------------------------------------------------
  *
  * miscadmin.h
- *	  this file contains general postgres administration and initialization
+ *	  This file contains general postgres administration and initialization
  *	  stuff that used to be spread out between the following files:
  *		globals.h						global variables
  *		pdir.h							directory path crud
  *		pinit.h							postgres initialization
  *		pmod.h							processing modes
- *
+ *	  Over time, this has also become the preferred place for widely known
+ *	  resource-limitation stuff, such as work_mem and check_stack_depth().
  *
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/miscadmin.h,v 1.154 2004/03/23 01:23:48 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/miscadmin.h,v 1.155 2004/03/24 22:40:29 tgl Exp $
  *
  * NOTES
  *	  some of the information in this file should be moved to
@@ -70,7 +71,7 @@ extern volatile bool ImmediateInterruptOK;
 extern volatile uint32 InterruptHoldoffCount;
 extern volatile uint32 CritSectionCount;
 
-/* in postgres.c */
+/* in tcop/postgres.c */
 extern void ProcessInterrupts(void);
 
 #ifndef WIN32
@@ -224,6 +225,10 @@ extern char *UnixSocketDir;
 extern char *ListenAddresses;
 
 
+/* in tcop/postgres.c */
+extern void check_stack_depth(void);
+
+
 /*****************************************************************************
  *	  pdir.h --																 *
  *			POSTGRES directory path definitions.							 *
diff --git a/src/include/parser/parse_expr.h b/src/include/parser/parse_expr.h
index d5b87da1b7..a8be03a534 100644
--- a/src/include/parser/parse_expr.h
+++ b/src/include/parser/parse_expr.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/parser/parse_expr.h,v 1.32 2003/11/29 22:41:09 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/parser/parse_expr.h,v 1.33 2004/03/24 22:40:29 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -18,7 +18,6 @@
 
 
 /* GUC parameters */
-extern int	max_expr_depth;
 extern bool Transform_null_equals;
 
 
@@ -26,6 +25,5 @@ extern Node *transformExpr(ParseState *pstate, Node *expr);
 extern Oid	exprType(Node *expr);
 extern int32 exprTypmod(Node *expr);
 extern bool exprIsLengthCoercion(Node *expr, int32 *coercedTypmod);
-extern void parse_expr_init(void);
 
 #endif   /* PARSE_EXPR_H */
diff --git a/src/include/pg_config_manual.h b/src/include/pg_config_manual.h
index 6fcf38ec7b..87ddd1f196 100644
--- a/src/include/pg_config_manual.h
+++ b/src/include/pg_config_manual.h
@@ -6,7 +6,7 @@
  * for developers.	If you edit any of these, be sure to do a *full*
  * rebuild (and an initdb if noted).
  *
- * $PostgreSQL: pgsql/src/include/pg_config_manual.h,v 1.11 2004/03/12 00:25:40 neilc Exp $
+ * $PostgreSQL: pgsql/src/include/pg_config_manual.h,v 1.12 2004/03/24 22:40:29 tgl Exp $
  *------------------------------------------------------------------------
  */
 
@@ -113,11 +113,6 @@
 #define MAXPGPATH		1024
 
 /*
- * DEFAULT_MAX_EXPR_DEPTH: default value of max_expr_depth SET variable.
- */
-#define DEFAULT_MAX_EXPR_DEPTH	10000
-
-/*
  * PG_SOMAXCONN: maximum accept-queue length limit passed to
  * listen(2).  You'd think we should use SOMAXCONN from
  * <sys/socket.h>, but on many systems that symbol is much smaller
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index 20c84dd925..b2520b210e 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/tcop/tcopprot.h,v 1.62 2004/03/15 15:56:27 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/tcop/tcopprot.h,v 1.63 2004/03/24 22:40:29 tgl Exp $
  *
  * OLD COMMENTS
  *	  This file was created so that other c files could get the two
@@ -23,6 +23,7 @@
 
 #include "executor/execdesc.h"
 #include "tcop/dest.h"
+#include "utils/guc.h"
 
 
 extern DLLIMPORT sigjmp_buf Warn_restart;
@@ -32,6 +33,7 @@ extern CommandDest whereToSendOutput;
 extern bool log_hostname;
 extern DLLIMPORT const char *debug_query_string;
 extern char *rendezvous_name;
+extern int	max_stack_depth;
 
 #ifndef BOOTSTRAP_INCLUDE
 
@@ -43,6 +45,9 @@ extern List *pg_analyze_and_rewrite(Node *parsetree,
 extern List *pg_rewrite_queries(List *querytree_list);
 extern Plan *pg_plan_query(Query *querytree);
 extern List *pg_plan_queries(List *querytrees, bool needSnapshot);
+
+extern bool assign_max_stack_depth(int newval, bool doit, GucSource source);
+
 #endif   /* BOOTSTRAP_INCLUDE */
 
 extern void die(SIGNAL_ARGS);