oss/luanti
oss/luanti
1
0
Fork 0
mirror of https://github.com/luanti-org/luanti.git synced 2025-06-27 16:36:03 +00:00
Code Wiki Activity

Improve minetest.parse_json

Browse source 
Let modders handle parsing errors, get rid of two unnecessary copies.
This commit is contained in:
Lars Mueller 2024-10-12 23:24:47 +02:00 • committed by Lars Müller
parent c7938ce81c
commit 4c419c4020
3 changed files with 48 additions and 35 deletions
Download patch file Download diff file Expand all files Collapse all files

54
src/script/lua_api/l_util.cpp
View file

@ -93,12 +93,12 @@ int ModApiUtil::l_get_us_time(lua_State *L)
return 1;
}
// parse_json(str[, nullvalue])
// parse_json(str[, nullvalue, return_error])
int ModApiUtil::l_parse_json(lua_State *L)
{
NO_MAP_LOCK_REQUIRED;
const char *jsonstr = luaL_checkstring(L, 1);
const auto jsonstr = readParam<std::string_view>(L, 1);
// Use passed nullvalue or default to nil
int nullindex = 2;
@ -107,36 +107,38 @@ int ModApiUtil::l_parse_json(lua_State *L)
nullindex = lua_gettop(L);
}
bool return_error = lua_toboolean(L, 3);
const auto handle_error = [&](const char *errmsg) {
if (return_error) {
lua_pushnil(L);
lua_pushstring(L, errmsg);
return 2;
}
errorstream << "Failed to parse json data: " << errmsg << std::endl;
errorstream << "data: \"";
if (jsonstr.size() <= 100) {
errorstream << jsonstr << "\"";
} else {
errorstream << jsonstr.substr(0, 100) << "\"... (truncated)";
}
errorstream << std::endl;
lua_pushnil(L);
return 1;
};
Json::Value root;
{
std::istringstream stream(jsonstr);
Json::CharReaderBuilder builder;
builder.settings_["collectComments"] = false;
std::string errs;
if (!Json::parseFromStream(builder, stream, &root, &errs)) {
errorstream << "Failed to parse json data " << errs << std::endl;
size_t jlen = strlen(jsonstr);
if (jlen > 100) {
errorstream << "Data (" << jlen
<< " bytes) printed to warningstream." << std::endl;
warningstream << "data: \"" << jsonstr << "\"" << std::endl;
} else {
errorstream << "data: \"" << jsonstr << "\"" << std::endl;
}
lua_pushnil(L);
return 1;
}
const std::unique_ptr<Json::CharReader> reader(builder.newCharReader());
std::string errmsg;
if (!reader->parse(jsonstr.begin(), jsonstr.end(), &root, &errmsg))
return handle_error(errmsg.c_str());
}
if (!push_json_value(L, root, nullindex)) {
errorstream << "Failed to parse json data, "
<< "depth exceeds lua stack limit" << std::endl;
errorstream << "data: \"" << jsonstr << "\"" << std::endl;
lua_pushnil(L);
}
if (!push_json_value(L, root, nullindex))
return handle_error("depth exceeds lua stack limit");
return 1;
}