MDEV-11470 JSON_KEYS accepts arguments in invalid format.

        Now JSON functions return warnings if arguments are invalid.

include/json_lib.h

@@ -102,6 +102,7 @@ typedef struct st_json_path_t
   json_path_step_t *last_step; /* Points to the last step. */
 
   int mode_strict; /* TRUE if the path specified as 'strict' */
+  enum json_path_step_types types_used; /* The '|' of all step's 'type'-s */
 } json_path_t;
 
 

mysql-test/r/func_json.result

@@ -92,7 +92,9 @@ select json_contains('[1]', '[1]', '$', '$[0]');
 ERROR 42000: Incorrect parameter count in the call to native function 'json_contains'
 select json_contains('', '', '$');
 json_contains('', '', '$')
-0
+NULL
+Warnings:
+Warning	4037	Unexpected end of JSON text in argument 1 to function 'json_contains'
 select json_contains('null', 'null', '$');
 json_contains('null', 'null', '$')
 1
@@ -276,6 +278,8 @@ ERROR 42000: Incorrect parameter count in the call to native function 'json_merg
 select json_merge('string', 123);
 json_merge('string', 123)
 NULL
+Warnings:
+Warning	4038	Syntax error in JSON text in argument 1 to function 'json_merge' at position 1
 select json_merge('"string"', 123);
 json_merge('"string"', 123)
 ["string", 123]
@@ -294,6 +298,8 @@ NULL
 select json_merge('a','b');
 json_merge('a','b')
 NULL
+Warnings:
+Warning	4038	Syntax error in JSON text in argument 1 to function 'json_merge' at position 1
 select json_merge('{"a":"b"}','{"c":"d"}');
 json_merge('{"a":"b"}','{"c":"d"}')
 {"a":"b", "c":"d"}
@@ -321,6 +327,11 @@ json_keys('{"a":{"c":1, "d":2}, "b":2}', "$.a")
 select json_keys('{"a":{"c":1, "d":2}, "b":2}', "$.b");
 json_keys('{"a":{"c":1, "d":2}, "b":2}', "$.b")
 NULL
+select json_keys('foo');
+json_keys('foo')
+NULL
+Warnings:
+Warning	4038	Syntax error in JSON text in argument 1 to function 'json_keys' at position 1
 SET @j = '["abc", [{"k": "10"}, "def"], {"x":"abc"}, {"y":"bcd"}]';
 select json_search(@j, 'one', 'abc');
 json_search(@j, 'one', 'abc')
@@ -385,6 +396,8 @@ json_depth('[[[1,2,3],"s"], {}, []]')
 select json_length('');
 json_length('')
 NULL
+Warnings:
+Warning	4037	Unexpected end of JSON text in argument 1 to function 'json_length'
 select json_length('{}');
 json_length('{}')
 0

mysql-test/t/func_json.test

@@ -129,6 +129,7 @@ select json_type('123.12');
 select json_keys('{"a":{"c":1, "d":2}, "b":2}');
 select json_keys('{"a":{"c":1, "d":2}, "b":2}', "$.a");
 select json_keys('{"a":{"c":1, "d":2}, "b":2}', "$.b");
+select json_keys('foo');
 
 SET @j = '["abc", [{"k": "10"}, "def"], {"x":"abc"}, {"y":"bcd"}]';
 select json_search(@j, 'one', 'abc');

sql/share/errmsg-utf8.txt

@@ -7414,3 +7414,27 @@ ER_BINLOG_NON_SUPPORTED_BULK
         eng "Only row based replication supported for bulk operations"
 ER_BINLOG_UNCOMPRESS_ERROR
         eng "Uncompress the compressed binlog failed"
+ER_JSON_BAD_CHR
+        eng "Broken JSON string in argument %d to function '%s' at position %d"
+ER_JSON_NOT_JSON_CHR
+        eng "Character disallowd in JSON in argument %d to function '%s' at position %d"
+ER_JSON_EOS
+        eng "Unexpected end of JSON text in argument %d to function '%s'"
+ER_JSON_SYNTAX
+        eng "Syntax error in JSON text in argument %d to function '%s' at position %d"
+ER_JSON_ESCAPING
+        eng "Incorrect escaping in JSON text in argument %d to function '%s' at position %d"
+ER_JSON_DEPTH
+        eng "Limit of %d on JSON nested strucures depth is reached in argument %d to function '%s' at position %d"
+ER_JSON_PATH_EOS
+        eng "Unexpected end of JSON path in argument %d to function '%s'"
+ER_JSON_PATH_SYNTAX
+        eng "Syntax error in JSON path in argument %d to function '%s' at position %d"
+ER_JSON_PATH_DEPTH
+        eng "Limit of %d on JSON path depth is reached in argument %d to function '%s' at position %d"
+ER_JSON_PATH_NO_WILDCARD
+        eng "Wildcards in JSON path not allowed in argument %d to function '%s'"
+ER_JSON_PATH_ARRAY
+        eng "JSON path should end with an array identifier in argument %d to function '%s'"
+ER_JSON_ONE_OR_ALL
+        eng "Argument 2 to function '%s' must be "one" or "all"."

strings/json_lib.c

@@ -392,12 +392,12 @@ static int v_string(json_engine_t *j)
 static int read_strn(json_engine_t *j)
 {
   j->value= j->s.c_str;
+  j->value_type= JSON_VALUE_STRING;
 
   if (skip_str_constant(j))
     return 1;
 
   j->state= *j->stack_p;
-  j->value_type= JSON_VALUE_STRING;
   j->value_len= (j->s.c_str - j->value) - 1;
   return 0;
 }
@@ -556,9 +556,9 @@ static int skip_string_verbatim(json_string_t *s, const char *str)
         s->c_str+= c_len;
         continue;
       }
-      return JE_SYN;
+      return s->error= JE_SYN;
     }
-    return json_eos(s) ? JE_EOS : JE_BAD_CHR; 
+    return s->error= json_eos(s) ? JE_EOS : JE_BAD_CHR; 
   }
 
   return 0;
@@ -1078,6 +1078,7 @@ int json_path_setup(json_path_t *p,
   p->steps[0].type= JSON_PATH_ARRAY_WILD;
   p->last_step= p->steps;
   p->mode_strict= FALSE;
+  p->types_used= JSON_PATH_KEY_NULL;
 
   do
   {
@@ -1109,6 +1110,7 @@ int json_path_setup(json_path_t *p,
       if (p->last_step->type & JSON_PATH_DOUBLE_WILD)
         return p->s.error= JE_SYN;
       p->last_step->type|= JSON_PATH_WILD;
+      p->types_used|= JSON_PATH_WILD;
       continue;
     case PS_INT:
       p->last_step->n_item*= 10;
@@ -1122,7 +1124,7 @@ int json_path_setup(json_path_t *p,
       p->last_step++;
       if (p->last_step - p->steps >= JSON_DEPTH_LIMIT)
         return p->s.error= JE_DEPTH;
-      p->last_step->type= JSON_PATH_KEY | double_wildcard;
+      p->types_used|= p->last_step->type= JSON_PATH_KEY | double_wildcard;
       double_wildcard= JSON_PATH_KEY_NULL;
       p->last_step->key= p->s.c_str;
       continue;
@@ -1134,7 +1136,7 @@ int json_path_setup(json_path_t *p,
       p->last_step++;
       if (p->last_step - p->steps >= JSON_DEPTH_LIMIT)
         return p->s.error= JE_DEPTH;
-      p->last_step->type= JSON_PATH_ARRAY | double_wildcard;
+      p->types_used|= p->last_step->type= JSON_PATH_ARRAY | double_wildcard;
       double_wildcard= JSON_PATH_KEY_NULL;
       p->last_step->n_item= 0;
       continue;