MDEV-37082: Sig 11 in json_normalize_sort

Analysis:
json_valid() does not call any function recursively so insertion in the
table works ok. Since the depth of json is 5000, json_normalize()
recursively calls json_normalize_sort(), json_norm_to_string() and
json_norm_value_free() and we hit the stack limit.
Fix:
Get rid of the recursive nature of the functions and make them iterative.
This way we will never hit stack limit for bigger depths.

Author: mariadb-RuchaDeodhar

mysql-test/main/mdev_32854.result

@@ -452,3 +452,14 @@ SELECT JSON_VALUE(@json_doc_arr_lev45_valid, '$[1][1][1][1][1][1][1][1][1][1][1]
 JSON_VALUE(@json_doc_arr_lev45_valid, '$[1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1]')
 45
 DROP TABLE t1 ,t2;
+#
+# MDEV-37082: Sig 11 in json_normalize_sort
+#
+CREATE TABLE t (a JSON)Engine=InnoDB;
+INSERT INTO t VALUES (CONCAT (REPEAT('{"v":',5000),'1',REPEAT('}',5000)));
+INSERT INTO t VALUES (CONCAT (REPEAT('[',5000),'1',REPEAT(']',5000)));
+SELECT JSON_EQUALS (a,a) FROM t;
+JSON_EQUALS (a,a)
+1
+1
+DROP TABLE t;

mysql-test/main/mdev_32854.test

@@ -90,7 +90,6 @@ SELECT JSON_SCHEMA_VALID(@json_schema, @json_doc_obj_lev45_valid) AS found_path;
 SELECT JSON_SCHEMA_VALID(@json_schema, @json_doc_obj_lev45_valid2);
 
 
-
 SELECT JSON_SEARCH(@json_doc_obj_lev45_valid,'one', 'This is level 45');
 
 SET @json_updated = JSON_SET(@json_doc_obj_lev45_valid, 
@@ -111,3 +110,18 @@ SELECT JSON_VALUE(@json_doc_obj_lev45_valid, '$.level1.level2.level3.level4.leve
 SELECT JSON_VALUE(@json_doc_arr_lev45_valid, '$[1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1][1]');
 
 DROP TABLE t1 ,t2;
+
+--echo #
+--echo # MDEV-37082: Sig 11 in json_normalize_sort
+--echo #
+
+--source include/have_innodb.inc
+
+CREATE TABLE t (a JSON)Engine=InnoDB;
+
+INSERT INTO t VALUES (CONCAT (REPEAT('{"v":',5000),'1',REPEAT('}',5000)));
+INSERT INTO t VALUES (CONCAT (REPEAT('[',5000),'1',REPEAT(']',5000)));
+
+SELECT JSON_EQUALS (a,a) FROM t;
+
+DROP TABLE t;