From 3b76622e04d8656fb44e7c932cb243e2d92fe40e Mon Sep 17 00:00:00 2001
From: Andrew Dunstan <andrew@dunslane.net>
Date: Wed, 28 Dec 2022 09:53:00 -0500
Subject: [PATCH] Convert contrib/intarray's bqarr_in() to report errors softly

Reviewed by Tom Lane and Amul Sul

Discussion: https://postgr.es/m/49e598c2-cfe8-0928-b6fb-d0cc51aab626@dunslane.net
---
 contrib/intarray/_int_bool.c       | 15 +++++++++------
 contrib/intarray/expected/_int.out | 15 +++++++++++++++
 contrib/intarray/sql/_int.sql      | 11 +++++++++++
 3 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/contrib/intarray/_int_bool.c b/contrib/intarray/_int_bool.c
index 3ed88af76d..8fc6ad87fc 100644
--- a/contrib/intarray/_int_bool.c
+++ b/contrib/intarray/_int_bool.c
@@ -35,6 +35,7 @@ typedef struct
 	char	   *buf;
 	int32		state;
 	int32		count;
+	struct Node *escontext;
 	/* reverse polish notation in list (for temporary usage) */
 	NODE	   *str;
 	/* number in str */
@@ -179,7 +180,7 @@ makepol(WORKSTATE *state)
 				else
 				{
 					if (lenstack == STACKDEPTH)
-						ereport(ERROR,
+						ereturn(state->escontext, ERR,
 								(errcode(ERRCODE_STATEMENT_TOO_COMPLEX),
 								 errmsg("statement too complex")));
 					stack[lenstack] = val;
@@ -206,10 +207,9 @@ makepol(WORKSTATE *state)
 				break;
 			case ERR:
 			default:
-				ereport(ERROR,
+				ereturn(state->escontext, ERR,
 						(errcode(ERRCODE_SYNTAX_ERROR),
 						 errmsg("syntax error")));
-				return ERR;
 		}
 	}
 
@@ -483,6 +483,7 @@ bqarr_in(PG_FUNCTION_ARGS)
 	ITEM	   *ptr;
 	NODE	   *tmp;
 	int32		pos = 0;
+	struct Node *escontext = fcinfo->context;
 
 #ifdef BS_DEBUG
 	StringInfoData pbuf;
@@ -493,16 +494,18 @@ bqarr_in(PG_FUNCTION_ARGS)
 	state.count = 0;
 	state.num = 0;
 	state.str = NULL;
+	state.escontext = escontext;
 
 	/* make polish notation (postfix, but in reverse order) */
-	makepol(&state);
+	if (makepol(&state) == ERR)
+		PG_RETURN_NULL();
 	if (!state.num)
-		ereport(ERROR,
+		ereturn(escontext, (Datum) 0,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("empty query")));
 
 	if (state.num > QUERYTYPEMAXITEMS)
-		ereport(ERROR,
+		ereturn(escontext, (Datum) 0,
 				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
 				 errmsg("number of query items (%d) exceeds the maximum allowed (%d)",
 						state.num, (int) QUERYTYPEMAXITEMS)));
diff --git a/contrib/intarray/expected/_int.out b/contrib/intarray/expected/_int.out
index a09d40efa1..c953065a5c 100644
--- a/contrib/intarray/expected/_int.out
+++ b/contrib/intarray/expected/_int.out
@@ -398,6 +398,21 @@ SELECT '1&(2&(4&(5|!6)))'::query_int;
  1 & 2 & 4 & ( 5 | !6 )
 (1 row)
 
+-- test non-error-throwing input
+SELECT str as "query_int",
+       pg_input_is_valid(str,'query_int') as ok,
+       pg_input_error_message(str,'query_int') as errmsg
+FROM (VALUES ('1&(2&(4&(5|6)))'),
+             ('1#(2&(4&(5&6)))'),
+             ('foo'))
+      AS a(str);
+    query_int    | ok |    errmsg    
+-----------------+----+--------------
+ 1&(2&(4&(5|6))) | t  | 
+ 1#(2&(4&(5&6))) | f  | syntax error
+ foo             | f  | syntax error
+(3 rows)
+
 CREATE TABLE test__int( a int[] );
 \copy test__int from 'data/test__int.data'
 ANALYZE test__int;
diff --git a/contrib/intarray/sql/_int.sql b/contrib/intarray/sql/_int.sql
index b26fc57e4d..4c9ba4c1fb 100644
--- a/contrib/intarray/sql/_int.sql
+++ b/contrib/intarray/sql/_int.sql
@@ -75,6 +75,17 @@ SELECT '1&2&4&5&6'::query_int;
 SELECT '1&(2&(4&(5|6)))'::query_int;
 SELECT '1&(2&(4&(5|!6)))'::query_int;
 
+-- test non-error-throwing input
+
+SELECT str as "query_int",
+       pg_input_is_valid(str,'query_int') as ok,
+       pg_input_error_message(str,'query_int') as errmsg
+FROM (VALUES ('1&(2&(4&(5|6)))'),
+             ('1#(2&(4&(5&6)))'),
+             ('foo'))
+      AS a(str);
+
+
 
 CREATE TABLE test__int( a int[] );
 \copy test__int from 'data/test__int.data'