[ruby/json] Fix missing write barrier on Generator State

Found by wbcheck

   WBCHECK ERROR: Missed write barrier detected!
     Parent object: 0x7b7b8487c450 (wb_protected: true)
       rb_obj_info_dump: 0x00007b7b8487c450 JSON/Generator/State/JSON::Ext::Generator::State JSON/Generator/State
     Reference counts - snapshot: 1, writebarrier: 0, current: 6, missed: 5
     Missing reference to: 0x7b7b82f35a10
       rb_obj_info_dump: 0x00007b7b82f35a10 T_STRING/String  len: 1, capa: 15 "1"
     Missing reference to: 0x7b7b82f35e90
       rb_obj_info_dump: 0x00007b7b82f35e90 T_STRING/String  len: 1, capa: 15 "2"
     Missing reference to: 0x7b7b83629e50
       rb_obj_info_dump: 0x00007b7b83629e50 T_STRING/String  len: 1, capa: 15 "3"
     Missing reference to: 0x7b7b83b62190
       rb_obj_info_dump: 0x00007b7b83b62190 T_STRING/String  len: 1, capa: 15 "4"
     Missing reference to: 0x7b7b83629490
       rb_obj_info_dump: 0x00007b7b83629490 T_STRING/String  len: 1, capa: 15 "5"

c24342d801
This commit is contained in:
John Hawthorn 2025-07-23 10:27:08 -07:00 committed by Hiroshi SHIBATA
parent da3c47bcfc
commit b48904273a

View file

@ -1907,15 +1907,30 @@ static VALUE cState_buffer_initial_length_set(VALUE self, VALUE buffer_initial_l
return Qnil;
}
struct configure_state_data {
JSON_Generator_State *state;
VALUE vstate; // Ruby object that owns the state, or Qfalse if stack-allocated
};
static inline void state_write_value(struct configure_state_data *data, VALUE *field, VALUE value)
{
if (RTEST(data->vstate)) {
RB_OBJ_WRITE(data->vstate, field, value);
} else {
*field = value;
}
}
static int configure_state_i(VALUE key, VALUE val, VALUE _arg)
{
JSON_Generator_State *state = (JSON_Generator_State *)_arg;
struct configure_state_data *data = (struct configure_state_data *)_arg;
JSON_Generator_State *state = data->state;
if (key == sym_indent) { state->indent = string_config(val); }
else if (key == sym_space) { state->space = string_config(val); }
else if (key == sym_space_before) { state->space_before = string_config(val); }
else if (key == sym_object_nl) { state->object_nl = string_config(val); }
else if (key == sym_array_nl) { state->array_nl = string_config(val); }
if (key == sym_indent) { state_write_value(data, &state->indent, string_config(val)); }
else if (key == sym_space) { state_write_value(data, &state->space, string_config(val)); }
else if (key == sym_space_before) { state_write_value(data, &state->space_before, string_config(val)); }
else if (key == sym_object_nl) { state_write_value(data, &state->object_nl, string_config(val)); }
else if (key == sym_array_nl) { state_write_value(data, &state->array_nl, string_config(val)); }
else if (key == sym_max_nesting) { state->max_nesting = long_config(val); }
else if (key == sym_allow_nan) { state->allow_nan = RTEST(val); }
else if (key == sym_ascii_only) { state->ascii_only = RTEST(val); }
@ -1924,11 +1939,14 @@ static int configure_state_i(VALUE key, VALUE val, VALUE _arg)
else if (key == sym_script_safe) { state->script_safe = RTEST(val); }
else if (key == sym_escape_slash) { state->script_safe = RTEST(val); }
else if (key == sym_strict) { state->strict = RTEST(val); }
else if (key == sym_as_json) { state->as_json = RTEST(val) ? rb_convert_type(val, T_DATA, "Proc", "to_proc") : Qfalse; }
else if (key == sym_as_json) {
VALUE proc = RTEST(val) ? rb_convert_type(val, T_DATA, "Proc", "to_proc") : Qfalse;
state_write_value(data, &state->as_json, proc);
}
return ST_CONTINUE;
}
static void configure_state(JSON_Generator_State *state, VALUE config)
static void configure_state(JSON_Generator_State *state, VALUE vstate, VALUE config)
{
if (!RTEST(config)) return;
@ -1936,15 +1954,20 @@ static void configure_state(JSON_Generator_State *state, VALUE config)
if (!RHASH_SIZE(config)) return;
struct configure_state_data data = {
.state = state,
.vstate = vstate
};
// We assume in most cases few keys are set so it's faster to go over
// the provided keys than to check all possible keys.
rb_hash_foreach(config, configure_state_i, (VALUE)state);
rb_hash_foreach(config, configure_state_i, (VALUE)&data);
}
static VALUE cState_configure(VALUE self, VALUE opts)
{
GET_STATE(self);
configure_state(state, opts);
configure_state(state, self, opts);
return self;
}
@ -1952,7 +1975,7 @@ static VALUE cState_m_generate(VALUE klass, VALUE obj, VALUE opts, VALUE io)
{
JSON_Generator_State state = {0};
state_init(&state);
configure_state(&state, opts);
configure_state(&state, Qfalse, opts);
char stack_buffer[FBUFFER_STACK_SIZE];
FBuffer buffer = {