From 199432ea2258707fac4c22bcda509f3c4d5177ae Mon Sep 17 00:00:00 2001
From: Jeevan Ladhe <jeevan.ladhe@enterprisedb.com>
Date: Thu, 1 Aug 2019 11:55:30 +0530
Subject: [PATCH] Make the have_error flag initialization more defensive.

Basically get rid of the dependency to have caller
initalize the flag.
This patch addresses such occurrences in following functions:
pg_lsn_in_internal(), float8in_internal_opt_error(),
numeric_mod_opt_error(), numeric_div_opt_error() and
numeric_mod_opt_error().

Jeevan Ladhe
---
 src/backend/utils/adt/float.c         |  3 +++
 src/backend/utils/adt/jsonpath_exec.c |  6 +++---
 src/backend/utils/adt/numeric.c       |  9 +++++++++
 src/backend/utils/adt/pg_lsn.c        | 13 ++++++++++---
 src/backend/utils/misc/guc.c          |  2 +-
 5 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c
index 7540ca2..d40dc6c 100644
--- a/src/backend/utils/adt/float.c
+++ b/src/backend/utils/adt/float.c
@@ -376,6 +376,9 @@ float8in_internal_opt_error(char *num, char **endptr_p,
 	double		val;
 	char	   *endptr;
 
+	if (have_error)
+		*have_error = false;
+
 	/* skip leading whitespace */
 	while (*num != '\0' && isspace((unsigned char) *num))
 		num++;
diff --git a/src/backend/utils/adt/jsonpath_exec.c b/src/backend/utils/adt/jsonpath_exec.c
index 293d6da..a0ead39 100644
--- a/src/backend/utils/adt/jsonpath_exec.c
+++ b/src/backend/utils/adt/jsonpath_exec.c
@@ -976,7 +976,7 @@ executeItemOptUnwrapTarget(JsonPathExecContext *cxt, JsonPathItem *jsp,
 				{
 					char	   *tmp = DatumGetCString(DirectFunctionCall1(numeric_out,
 																		  NumericGetDatum(jb->val.numeric)));
-					bool		have_error = false;
+					bool		have_error;
 
 					(void) float8in_internal_opt_error(tmp,
 													   NULL,
@@ -997,7 +997,7 @@ executeItemOptUnwrapTarget(JsonPathExecContext *cxt, JsonPathItem *jsp,
 					double		val;
 					char	   *tmp = pnstrdup(jb->val.string.val,
 											   jb->val.string.len);
-					bool		have_error = false;
+					bool		have_error;
 
 					val = float8in_internal_opt_error(tmp,
 													  NULL,
@@ -1521,7 +1521,7 @@ executeBinaryArithmExpr(JsonPathExecContext *cxt, JsonPathItem *jsp,
 	}
 	else
 	{
-		bool		error = false;
+		bool		error;
 
 		res = func(lval->val.numeric, rval->val.numeric, &error);
 
diff --git a/src/backend/utils/adt/numeric.c b/src/backend/utils/adt/numeric.c
index 201784b..7b0874b 100644
--- a/src/backend/utils/adt/numeric.c
+++ b/src/backend/utils/adt/numeric.c
@@ -2605,6 +2605,9 @@ numeric_div_opt_error(Numeric num1, Numeric num2, bool *have_error)
 	Numeric		res;
 	int			rscale;
 
+	if(have_error)
+		*have_error = false;
+
 	/*
 	 * Handle NaN
 	 */
@@ -2721,6 +2724,9 @@ numeric_mod_opt_error(Numeric num1, Numeric num2, bool *have_error)
 	NumericVar	arg2;
 	NumericVar	result;
 
+	if (have_error)
+		*have_error = false;
+
 	if (NUMERIC_IS_NAN(num1) || NUMERIC_IS_NAN(num2))
 		return make_result(&const_nan);
 
@@ -6249,6 +6255,9 @@ make_result_opt_error(const NumericVar *var, bool *have_error)
 	int			n;
 	Size		len;
 
+	if (have_error)
+		*have_error = false;
+
 	if (sign == NUMERIC_NAN)
 	{
 		result = (Numeric) palloc(NUMERIC_HDRSZ_SHORT);
diff --git a/src/backend/utils/adt/pg_lsn.c b/src/backend/utils/adt/pg_lsn.c
index b4c6c23..3a3490f 100644
--- a/src/backend/utils/adt/pg_lsn.c
+++ b/src/backend/utils/adt/pg_lsn.c
@@ -34,17 +34,24 @@ pg_lsn_in_internal(const char *str, bool *have_error)
 				off;
 	XLogRecPtr	result;
 
+	if (have_error)
+		*have_error = false;
+
 	/* Sanity check input format. */
 	len1 = strspn(str, "0123456789abcdefABCDEF");
 	if (len1 < 1 || len1 > MAXPG_LSNCOMPONENT || str[len1] != '/')
 	{
-		*have_error = true;
+		if (have_error)
+			*have_error = true;
+
 		return InvalidXLogRecPtr;
 	}
 	len2 = strspn(str + len1 + 1, "0123456789abcdefABCDEF");
 	if (len2 < 1 || len2 > MAXPG_LSNCOMPONENT || str[len1 + 1 + len2] != '\0')
 	{
-		*have_error = true;
+		if (have_error)
+			*have_error = true;
+
 		return InvalidXLogRecPtr;
 	}
 
@@ -61,7 +68,7 @@ pg_lsn_in(PG_FUNCTION_ARGS)
 {
 	char	   *str = PG_GETARG_CSTRING(0);
 	XLogRecPtr	result;
-	bool		have_error = false;
+	bool		have_error;
 
 	result = pg_lsn_in_internal(str, &have_error);
 	if (have_error)
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index fc46360..ce179fc 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -11677,7 +11677,7 @@ check_recovery_target_lsn(char **newval, void **extra, GucSource source)
 	{
 		XLogRecPtr	lsn;
 		XLogRecPtr *myextra;
-		bool		have_error = false;
+		bool		have_error;
 
 		lsn = pg_lsn_in_internal(*newval, &have_error);
 		if (have_error)
-- 
2.7.4