static void json_append_number(lua_State *l, json_config_t *cfg,
strbuf_t *json, int lindex)
{
double num = lua_tonumber(l, lindex);
int len;
if (cfg->encode_invalid_numbers == 0) {
/* Prevent encoding invalid numbers */
if (isinf(num) || isnan(num))
json_encode_exception(l, cfg, json, lindex, "must not be NaN or Inf");
} else if (cfg->encode_invalid_numbers == 1) {
/* Encode invalid numbers, but handle "nan" separately
* since some platforms may encode as "-nan". */
if (isnan(num)) {
strbuf_append_mem(json, "nan", 3);
return;
}
} else {
/* Encode invalid numbers as "null" */
if (isinf(num) || isnan(num)) {
strbuf_append_mem(json, "null", 4);
return;
}
}
strbuf_ensure_empty_length(json, FPCONV_G_FMT_BUFSIZE);
len = fpconv_g_fmt(strbuf_empty_ptr(json), num, cfg->encode_number_precision);
strbuf_extend_length(json, len);
}
static void json_append_number(lua_State *l, strbuf_t *json, int index,
json_config_t *cfg)
{
double num = lua_tonumber(l, index);
if (cfg->encode_refuse_badnum && (isinf(num) || isnan(num)))
json_encode_exception(l, cfg, index, "must not be NaN or Inf");
/* Lowest double printed with %.14g is 21 characters long:
* -1.7976931348623e+308
*
* Use 32 to include the \0, and a few extra just in case..
*/
strbuf_append_fmt(json, 32, cfg->number_fmt, num);
}
static void json_append_number(lua_State *l, json_config_t *cfg,
strbuf_t *json, int lindex)
{
int len;
#if LUA_VERSION_NUM >= 503
if (lua_isinteger(l, lindex)) {
lua_Integer num = lua_tointeger(l, lindex);
strbuf_ensure_empty_length(json, FPCONV_G_FMT_BUFSIZE); /* max length of int64 is 19 */
len = sprintf(strbuf_empty_ptr(json), LUA_INTEGER_FMT, num);
strbuf_extend_length(json, len);
return;
}
#endif
double num = lua_tonumber(l, lindex);
if (cfg->encode_invalid_numbers == 0) {
/* Prevent encoding invalid numbers */
if (isinf(num) || isnan(num))
json_encode_exception(l, cfg, json, lindex,
"must not be NaN or Infinity");
} else if (cfg->encode_invalid_numbers == 1) {
/* Encode NaN/Infinity separately to ensure Javascript compatible
* values are used. */
if (isnan(num)) {
strbuf_append_mem(json, "NaN", 3);
return;
}
if (isinf(num)) {
if (num < 0)
strbuf_append_mem(json, "-Infinity", 9);
else
strbuf_append_mem(json, "Infinity", 8);
return;
}
} else {
/* Encode invalid numbers as "null" */
if (isinf(num) || isnan(num)) {
strbuf_append_mem(json, "null", 4);
return;
}
}
strbuf_ensure_empty_length(json, FPCONV_G_FMT_BUFSIZE);
len = fpconv_g_fmt(strbuf_empty_ptr(json), num, cfg->encode_number_precision);
strbuf_extend_length(json, len);
}
static void json_append_object(lua_State *l, json_config_t *cfg,
strbuf_t *json)
{
int comma, keytype;
json_encode_descend(l, cfg);
/* Object */
strbuf_append_char(json, '{');
lua_pushnil(l);
/* table, startkey */
comma = 0;
while (lua_next(l, -2) != 0) {
if (comma)
strbuf_append_char(json, ',');
else
comma = 1;
/* table, key, value */
keytype = lua_type(l, -2);
if (keytype == LUA_TNUMBER) {
strbuf_append_char(json, '"');
json_append_number(l, json, -2, cfg);
strbuf_append_mem(json, "\":", 2);
} else if (keytype == LUA_TSTRING) {
json_append_string(l, json, -2);
strbuf_append_char(json, ':');
} else {
json_encode_exception(l, cfg, -2,
"table key must be a number or string");
/* never returns */
}
/* table, key, value */
json_append_data(l, cfg, json);
lua_pop(l, 1);
/* table, key */
}
strbuf_append_char(json, '}');
cfg->current_depth--;
}
/* Serialise Lua data into JSON string. */
static void json_append_data(lua_State *l, json_config_t *cfg,
int current_depth, strbuf_t *json)
{
int len;
switch (lua_type(l, -1)) {
case LUA_TSTRING:
json_append_string(l, json, -1);
break;
case LUA_TNUMBER:
json_append_number(l, cfg, json, -1);
break;
case LUA_TBOOLEAN:
if (lua_toboolean(l, -1))
strbuf_append_mem(json, "true", 4);
else
strbuf_append_mem(json, "false", 5);
break;
case LUA_TTABLE:
current_depth++;
json_check_encode_depth(l, cfg, current_depth, json);
len = lua_array_length(l, cfg, json);
if (len > 0)
json_append_array(l, cfg, current_depth, json, len);
else
json_append_object(l, cfg, current_depth, json);
break;
case LUA_TNIL:
strbuf_append_mem(json, "null", 4);
break;
case LUA_TLIGHTUSERDATA:
if (lua_touserdata(l, -1) == NULL) {
strbuf_append_mem(json, "null", 4);
break;
}
default:
/* Remaining types (LUA_TFUNCTION, LUA_TUSERDATA, LUA_TTHREAD,
* and LUA_TLIGHTUSERDATA) cannot be serialised */
json_encode_exception(l, cfg, json, -1, "type not supported");
/* never returns */
}
}
/* Find the size of the array on the top of the Lua stack
* -1 object (not a pure array)
* >=0 elements in array
*/
static int lua_array_length(lua_State *l, json_config_t *cfg, strbuf_t *json)
{
double k;
int max;
int items;
max = 0;
items = 0;
lua_pushnil(l);
/* table, startkey */
while (lua_next(l, -2) != 0) {
/* table, key, value */
if (lua_type(l, -2) == LUA_TNUMBER &&
(k = lua_tonumber(l, -2))) {
/* Integer >= 1 ? */
if (floor(k) == k && k >= 1) {
if (k > max)
max = k;
items++;
lua_pop(l, 1);
continue;
}
}
/* Must not be an array (non integer key) */
lua_pop(l, 2);
return -1;
}
/* Encode excessively sparse arrays as objects (if enabled) */
if (cfg->encode_sparse_ratio > 0 &&
max > items * cfg->encode_sparse_ratio &&
max > cfg->encode_sparse_safe) {
if (!cfg->encode_sparse_convert)
json_encode_exception(l, cfg, json, -1, "excessively sparse array");
return -1;
}
return max;
}