From fbb2b69c8f478c2910a32e25d80eaf67d0dd3cbf Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Tue, 2 Sep 2008 20:37:55 +0000
Subject: [PATCH] Prevent memory leaks in our various bison parsers when an
error occurs during parsing. Formerly the parser's stack was allocated with
malloc and so wouldn't be reclaimed; this patch makes it use palloc instead,
so that flushing the current context will reclaim the memory. Per Marko
Kreen.
---
contrib/cube/cubeparse.y | 13 ++++++++++++-
contrib/seg/segparse.y | 11 +++++++++++
src/backend/bootstrap/bootparse.y | 13 ++++++++++++-
src/backend/parser/gram.y | 13 ++++++++++++-
src/pl/plpgsql/src/gram.y | 14 +++++++++++++-
5 files changed, 60 insertions(+), 4 deletions(-)
diff --git a/contrib/cube/cubeparse.y b/contrib/cube/cubeparse.y
index e867dc8731a..eefe5c47b99 100644
--- a/contrib/cube/cubeparse.y
+++ b/contrib/cube/cubeparse.y
@@ -2,7 +2,7 @@
/* NdBox = [(lowerleft),(upperright)] */
/* [(xLL(1)...xLL(N)),(xUR(1)...xUR(n))] */
-/* $PostgreSQL: pgsql/contrib/cube/cubeparse.y,v 1.17 2007/02/27 23:48:05 tgl Exp $ */
+/* $PostgreSQL: pgsql/contrib/cube/cubeparse.y,v 1.18 2008/09/02 20:37:54 tgl Exp $ */
#define YYPARSE_PARAM result /* need this to pass a pointer (void *) to yyparse */
#define YYSTYPE char *
@@ -12,6 +12,17 @@
#include "cubedata.h"
+/*
+ * Bison doesn't allocate anything that needs to live across parser calls,
+ * so we can easily have it use palloc instead of malloc. This prevents
+ * memory leaks if we error out during parsing. Note this only works with
+ * bison >= 2.0. However, in bison 1.875 the default is to use alloca()
+ * if possible, so there's not really much problem anyhow, at least if
+ * you're building with gcc.
+ */
+#define YYMALLOC palloc
+#define YYFREE pfree
+
extern int cube_yylex(void);
static char *scanbuf;
diff --git a/contrib/seg/segparse.y b/contrib/seg/segparse.y
index dc56fb580fe..47e3d398aae 100644
--- a/contrib/seg/segparse.y
+++ b/contrib/seg/segparse.y
@@ -9,6 +9,17 @@
#include "utils/builtins.h"
#include "segdata.h"
+/*
+ * Bison doesn't allocate anything that needs to live across parser calls,
+ * so we can easily have it use palloc instead of malloc. This prevents
+ * memory leaks if we error out during parsing. Note this only works with
+ * bison >= 2.0. However, in bison 1.875 the default is to use alloca()
+ * if possible, so there's not really much problem anyhow, at least if
+ * you're building with gcc.
+ */
+#define YYMALLOC palloc
+#define YYFREE pfree
+
extern int seg_yylex(void);
extern int significant_digits(char *str); /* defined in seg.c */
diff --git a/src/backend/bootstrap/bootparse.y b/src/backend/bootstrap/bootparse.y
index 8019b244ae8..9997566002e 100644
--- a/src/backend/bootstrap/bootparse.y
+++ b/src/backend/bootstrap/bootparse.y
@@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/bootstrap/bootparse.y,v 1.93 2008/09/01 20:42:43 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/bootstrap/bootparse.y,v 1.94 2008/09/02 20:37:54 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -54,6 +54,17 @@
#define atooid(x) ((Oid) strtoul((x), NULL, 10))
+/*
+ * Bison doesn't allocate anything that needs to live across parser calls,
+ * so we can easily have it use palloc instead of malloc. This prevents
+ * memory leaks if we error out during parsing. Note this only works with
+ * bison >= 2.0. However, in bison 1.875 the default is to use alloca()
+ * if possible, so there's not really much problem anyhow, at least if
+ * you're building with gcc.
+ */
+#define YYMALLOC palloc
+#define YYFREE pfree
+
static void
do_start(void)
{
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 26a3198d37b..5c716dd8f22 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -11,7 +11,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.621 2008/09/01 20:42:44 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.622 2008/09/02 20:37:54 tgl Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
@@ -79,6 +79,17 @@
*/
#define base_yylex filtered_base_yylex
+/*
+ * Bison doesn't allocate anything that needs to live across parser calls,
+ * so we can easily have it use palloc instead of malloc. This prevents
+ * memory leaks if we error out during parsing. Note this only works with
+ * bison >= 2.0. However, in bison 1.875 the default is to use alloca()
+ * if possible, so there's not really much problem anyhow, at least if
+ * you're building with gcc.
+ */
+#define YYMALLOC palloc
+#define YYFREE pfree
+
extern List *parsetree; /* final parse result is delivered here */
static bool QueryIsRule = FALSE;
diff --git a/src/pl/plpgsql/src/gram.y b/src/pl/plpgsql/src/gram.y
index dfd37f67717..cf3c751cc0b 100644
--- a/src/pl/plpgsql/src/gram.y
+++ b/src/pl/plpgsql/src/gram.y
@@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.113 2008/05/15 22:39:49 tgl Exp $
+ * $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.114 2008/09/02 20:37:55 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -19,6 +19,18 @@
#include "parser/parser.h"
+/*
+ * Bison doesn't allocate anything that needs to live across parser calls,
+ * so we can easily have it use palloc instead of malloc. This prevents
+ * memory leaks if we error out during parsing. Note this only works with
+ * bison >= 2.0. However, in bison 1.875 the default is to use alloca()
+ * if possible, so there's not really much problem anyhow, at least if
+ * you're building with gcc.
+ */
+#define YYMALLOC palloc
+#define YYFREE pfree
+
+
static PLpgSQL_expr *read_sql_construct(int until,
int until2,
int until3,
--
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