/*
* This file is part of OpenTTD.
* OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
* OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see .
*/
/** @file script_instance.cpp Implementation of ScriptInstance. */
#include "../stdafx.h"
#include "../debug.h"
#include "../saveload/saveload.h"
#include "../script/squirrel_class.hpp"
#include "../script/squirrel_std.hpp"
#include "script_fatalerror.hpp"
#include "script_storage.hpp"
#include "script_info.hpp"
#include "script_instance.hpp"
#include "api/script_controller.hpp"
#include "api/script_error.hpp"
#include "api/script_event.hpp"
#include "api/script_log.hpp"
#include "../company_base.h"
#include "../company_func.h"
#include "../fileio_func.h"
#include "../league_type.h"
#include "../misc/endian_buffer.hpp"
#include "../safeguards.h"
ScriptStorage::~ScriptStorage()
{
/* Free our pointers */
if (event_data != nullptr) ScriptEventController::FreeEventPointer();
}
/**
* Callback called by squirrel when a script uses "print" and for error messages.
* @param error_msg Is this an error message?
* @param message The actual message text.
*/
static void PrintFunc(bool error_msg, const std::string &message)
{
/* Convert to OpenTTD internal capable string */
ScriptController::Print(error_msg, message.c_str());
}
ScriptInstance::ScriptInstance(const char *APIName) :
engine(nullptr),
controller(nullptr),
storage(nullptr),
instance(nullptr),
is_started(false),
is_dead(false),
is_save_data_on_stack(false),
suspend(0),
is_paused(false),
in_shutdown(false),
callback(nullptr)
{
this->storage = new ScriptStorage();
this->engine = new Squirrel(APIName);
this->engine->SetPrintFunction(&PrintFunc);
}
void ScriptInstance::Initialize(const std::string &main_script, const std::string &instance_name, CompanyID company)
{
ScriptObject::ActiveInstance active(this);
this->controller = new ScriptController(company);
/* Register the API functions and classes */
this->engine->SetGlobalPointer(this->engine);
this->RegisterAPI();
try {
ScriptObject::SetAllowDoCommand(false);
/* Load and execute the script for this script */
if (main_script == "%_dummy") {
this->LoadDummyScript();
} else if (!this->engine->LoadScript(main_script) || this->engine->IsSuspended()) {
if (this->engine->IsSuspended()) ScriptLog::Error("This script took too long to load script. AI is not started.");
this->Died();
return;
}
/* Create the main-class */
this->instance = new SQObject();
if (!this->engine->CreateClassInstance(instance_name, this->controller, this->instance)) {
/* If CreateClassInstance has returned false instance has not been
* registered with squirrel, so avoid trying to Release it by clearing it now */
delete this->instance;
this->instance = nullptr;
this->Died();
return;
}
ScriptObject::SetAllowDoCommand(true);
} catch (Script_FatalError &e) {
this->is_dead = true;
this->engine->ThrowError(e.GetErrorMessage());
this->engine->ResumeError();
this->Died();
}
}
void ScriptInstance::RegisterAPI()
{
squirrel_register_std(this->engine);
}
bool ScriptInstance::LoadCompatibilityScripts(const std::string &api_version, Subdirectory dir)
{
std::string script_name = fmt::format("compat_{}.nut", api_version);
for (Searchpath sp : _valid_searchpaths) {
std::string buf = FioGetDirectory(sp, dir);
buf += script_name;
if (!FileExists(buf)) continue;
if (this->engine->LoadScript(buf)) return true;
ScriptLog::Error("Failed to load API compatibility script");
Debug(script, 0, "Error compiling / running API compatibility script: {}", buf);
return false;
}
ScriptLog::Warning("API compatibility script not found");
return true;
}
ScriptInstance::~ScriptInstance()
{
ScriptObject::ActiveInstance active(this);
this->in_shutdown = true;
if (instance != nullptr) this->engine->ReleaseObject(this->instance);
if (engine != nullptr) delete this->engine;
delete this->storage;
delete this->controller;
delete this->instance;
}
void ScriptInstance::Continue()
{
assert(this->suspend < 0);
this->suspend = -this->suspend - 1;
}
void ScriptInstance::Died()
{
Debug(script, 0, "The script died unexpectedly.");
this->is_dead = true;
this->in_shutdown = true;
this->last_allocated_memory = this->GetAllocatedMemory(); // Update cache
if (this->instance != nullptr) this->engine->ReleaseObject(this->instance);
delete this->instance;
delete this->engine;
this->instance = nullptr;
this->engine = nullptr;
}
void ScriptInstance::GameLoop()
{
ScriptObject::ActiveInstance active(this);
if (this->IsDead()) return;
if (this->engine->HasScriptCrashed()) {
/* The script crashed during saving, kill it here. */
this->Died();
return;
}
if (this->is_paused) return;
this->controller->ticks++;
if (this->suspend < -1) this->suspend++; // Multiplayer suspend, increase up to -1.
if (this->suspend < 0) return; // Multiplayer suspend, wait for Continue().
if (--this->suspend > 0) return; // Singleplayer suspend, decrease to 0.
_current_company = ScriptObject::GetCompany();
/* If there is a callback to call, call that first */
if (this->callback != nullptr) {
if (this->is_save_data_on_stack) {
sq_poptop(this->engine->GetVM());
this->is_save_data_on_stack = false;
}
try {
this->callback(this);
} catch (Script_Suspend &e) {
this->suspend = e.GetSuspendTime();
this->callback = e.GetSuspendCallback();
return;
}
}
this->suspend = 0;
this->callback = nullptr;
if (!this->is_started) {
try {
ScriptObject::SetAllowDoCommand(false);
/* Run the constructor if it exists. Don't allow any DoCommands in it. */
if (this->engine->MethodExists(*this->instance, "constructor")) {
if (!this->engine->CallMethod(*this->instance, "constructor", MAX_CONSTRUCTOR_OPS) || this->engine->IsSuspended()) {
if (this->engine->IsSuspended()) ScriptLog::Error("This script took too long to initialize. Script is not started.");
this->Died();
return;
}
}
if (!this->CallLoad() || this->engine->IsSuspended()) {
if (this->engine->IsSuspended()) ScriptLog::Error("This script took too long in the Load function. Script is not started.");
this->Died();
return;
}
ScriptObject::SetAllowDoCommand(true);
/* Start the script by calling Start() */
if (!this->engine->CallMethod(*this->instance, "Start", _settings_game.script.script_max_opcode_till_suspend) || !this->engine->IsSuspended()) this->Died();
} catch (Script_Suspend &e) {
this->suspend = e.GetSuspendTime();
this->callback = e.GetSuspendCallback();
} catch (Script_FatalError &e) {
this->is_dead = true;
this->engine->ThrowError(e.GetErrorMessage());
this->engine->ResumeError();
this->Died();
}
this->is_started = true;
return;
}
if (this->is_save_data_on_stack) {
sq_poptop(this->engine->GetVM());
this->is_save_data_on_stack = false;
}
/* Continue the VM */
try {
if (!this->engine->Resume(_settings_game.script.script_max_opcode_till_suspend)) this->Died();
} catch (Script_Suspend &e) {
this->suspend = e.GetSuspendTime();
this->callback = e.GetSuspendCallback();
} catch (Script_FatalError &e) {
this->is_dead = true;
this->engine->ThrowError(e.GetErrorMessage());
this->engine->ResumeError();
this->Died();
}
}
void ScriptInstance::CollectGarbage()
{
if (this->is_started && !this->IsDead()) {
ScriptObject::ActiveInstance active(this);
this->engine->CollectGarbage();
}
}
/* static */ void ScriptInstance::DoCommandReturn(ScriptInstance *instance)
{
instance->engine->InsertResult(ScriptObject::GetLastCommandRes());
}
/* static */ void ScriptInstance::DoCommandReturnVehicleID(ScriptInstance *instance)
{
instance->engine->InsertResult(EndianBufferReader::ToValue(ScriptObject::GetLastCommandResData()));
}
/* static */ void ScriptInstance::DoCommandReturnSignID(ScriptInstance *instance)
{
instance->engine->InsertResult(EndianBufferReader::ToValue(ScriptObject::GetLastCommandResData()));
}
/* static */ void ScriptInstance::DoCommandReturnGroupID(ScriptInstance *instance)
{
instance->engine->InsertResult(EndianBufferReader::ToValue(ScriptObject::GetLastCommandResData()));
}
/* static */ void ScriptInstance::DoCommandReturnGoalID(ScriptInstance *instance)
{
instance->engine->InsertResult(EndianBufferReader::ToValue(ScriptObject::GetLastCommandResData()));
}
/* static */ void ScriptInstance::DoCommandReturnStoryPageID(ScriptInstance *instance)
{
instance->engine->InsertResult(EndianBufferReader::ToValue(ScriptObject::GetLastCommandResData()));
}
/* static */ void ScriptInstance::DoCommandReturnStoryPageElementID(ScriptInstance *instance)
{
instance->engine->InsertResult(EndianBufferReader::ToValue(ScriptObject::GetLastCommandResData()));
}
/* static */ void ScriptInstance::DoCommandReturnLeagueTableElementID(ScriptInstance *instance)
{
instance->engine->InsertResult(EndianBufferReader::ToValue(ScriptObject::GetLastCommandResData()));
}
/* static */ void ScriptInstance::DoCommandReturnLeagueTableID(ScriptInstance *instance)
{
instance->engine->InsertResult(EndianBufferReader::ToValue(ScriptObject::GetLastCommandResData()));
}
ScriptStorage *ScriptInstance::GetStorage()
{
return this->storage;
}
ScriptLogTypes::LogData &ScriptInstance::GetLogData()
{
ScriptObject::ActiveInstance active(this);
return ScriptObject::GetLogData();
}
/*
* All data is stored in the following format:
* First 1 byte indicating if there is a data blob at all.
* 1 byte indicating the type of data.
* The data itself, this differs per type:
* - integer: a binary representation of the integer (int32_t).
* - string: First one byte with the string length, then a 0-terminated char
* array. The string can't be longer than 255 bytes (including
* terminating '\0').
* - array: All data-elements of the array are saved recursive in this
* format, and ended with an element of the type
* SQSL_ARRAY_TABLE_END.
* - table: All key/value pairs are saved in this format (first key 1, then
* value 1, then key 2, etc.). All keys and values can have an
* arbitrary type (as long as it is supported by the save function
* of course). The table is ended with an element of the type
* SQSL_ARRAY_TABLE_END.
* - bool: A single byte with value 1 representing true and 0 false.
* - null: No data.
*/
static byte _script_sl_byte; ///< Used as source/target by the script saveload code to store/load a single byte.
/** SaveLoad array that saves/loads exactly one byte. */
static const SaveLoad _script_byte[] = {
SLEG_VAR("type", _script_sl_byte, SLE_UINT8),
};
/* static */ bool ScriptInstance::SaveObject(HSQUIRRELVM vm, SQInteger index, int max_depth, bool test)
{
if (max_depth == 0) {
ScriptLog::Error("Savedata can only be nested to 25 deep. No data saved."); // SQUIRREL_MAX_DEPTH = 25
return false;
}
switch (sq_gettype(vm, index)) {
case OT_INTEGER: {
if (!test) {
_script_sl_byte = SQSL_INT;
SlObject(nullptr, _script_byte);
}
SQInteger res;
sq_getinteger(vm, index, &res);
if (!test) {
int64_t value = (int64_t)res;
SlCopy(&value, 1, SLE_INT64);
}
return true;
}
case OT_STRING: {
if (!test) {
_script_sl_byte = SQSL_STRING;
SlObject(nullptr, _script_byte);
}
const SQChar *buf;
sq_getstring(vm, index, &buf);
size_t len = strlen(buf) + 1;
if (len >= 255) {
ScriptLog::Error("Maximum string length is 254 chars. No data saved.");
return false;
}
if (!test) {
_script_sl_byte = (byte)len;
SlObject(nullptr, _script_byte);
SlCopy(const_cast(buf), len, SLE_CHAR);
}
return true;
}
case OT_ARRAY: {
if (!test) {
_script_sl_byte = SQSL_ARRAY;
SlObject(nullptr, _script_byte);
}
sq_pushnull(vm);
while (SQ_SUCCEEDED(sq_next(vm, index - 1))) {
/* Store the value */
bool res = SaveObject(vm, -1, max_depth - 1, test);
sq_pop(vm, 2);
if (!res) {
sq_pop(vm, 1);
return false;
}
}
sq_pop(vm, 1);
if (!test) {
_script_sl_byte = SQSL_ARRAY_TABLE_END;
SlObject(nullptr, _script_byte);
}
return true;
}
case OT_TABLE: {
if (!test) {
_script_sl_byte = SQSL_TABLE;
SlObject(nullptr, _script_byte);
}
sq_pushnull(vm);
while (SQ_SUCCEEDED(sq_next(vm, index - 1))) {
/* Store the key + value */
bool res = SaveObject(vm, -2, max_depth - 1, test) && SaveObject(vm, -1, max_depth - 1, test);
sq_pop(vm, 2);
if (!res) {
sq_pop(vm, 1);
return false;
}
}
sq_pop(vm, 1);
if (!test) {
_script_sl_byte = SQSL_ARRAY_TABLE_END;
SlObject(nullptr, _script_byte);
}
return true;
}
case OT_BOOL: {
if (!test) {
_script_sl_byte = SQSL_BOOL;
SlObject(nullptr, _script_byte);
}
SQBool res;
sq_getbool(vm, index, &res);
if (!test) {
_script_sl_byte = res ? 1 : 0;
SlObject(nullptr, _script_byte);
}
return true;
}
case OT_NULL: {
if (!test) {
_script_sl_byte = SQSL_NULL;
SlObject(nullptr, _script_byte);
}
return true;
}
default:
ScriptLog::Error("You tried to save an unsupported type. No data saved.");
return false;
}
}
/* static */ void ScriptInstance::SaveEmpty()
{
_script_sl_byte = 0;
SlObject(nullptr, _script_byte);
}
void ScriptInstance::Save()
{
ScriptObject::ActiveInstance active(this);
/* Don't save data if the script didn't start yet or if it crashed. */
if (this->engine == nullptr || this->engine->HasScriptCrashed()) {
SaveEmpty();
return;
}
HSQUIRRELVM vm = this->engine->GetVM();
if (this->is_save_data_on_stack) {
_script_sl_byte = 1;
SlObject(nullptr, _script_byte);
/* Save the data that was just loaded. */
SaveObject(vm, -1, SQUIRREL_MAX_DEPTH, false);
} else if (!this->is_started) {
SaveEmpty();
return;
} else if (this->engine->MethodExists(*this->instance, "Save")) {
HSQOBJECT savedata;
/* We don't want to be interrupted during the save function. */
bool backup_allow = ScriptObject::GetAllowDoCommand();
ScriptObject::SetAllowDoCommand(false);
try {
if (!this->engine->CallMethod(*this->instance, "Save", &savedata, MAX_SL_OPS)) {
/* The script crashed in the Save function. We can't kill
* it here, but do so in the next script tick. */
SaveEmpty();
this->engine->CrashOccurred();
return;
}
} catch (Script_FatalError &e) {
/* If we don't mark the script as dead here cleaning up the squirrel
* stack could throw Script_FatalError again. */
this->is_dead = true;
this->engine->ThrowError(e.GetErrorMessage());
this->engine->ResumeError();
SaveEmpty();
/* We can't kill the script here, so mark it as crashed (not dead) and
* kill it in the next script tick. */
this->is_dead = false;
this->engine->CrashOccurred();
return;
}
ScriptObject::SetAllowDoCommand(backup_allow);
if (!sq_istable(savedata)) {
ScriptLog::Error(this->engine->IsSuspended() ? "This script took too long to Save." : "Save function should return a table.");
SaveEmpty();
this->engine->CrashOccurred();
return;
}
sq_pushobject(vm, savedata);
if (SaveObject(vm, -1, SQUIRREL_MAX_DEPTH, true)) {
_script_sl_byte = 1;
SlObject(nullptr, _script_byte);
SaveObject(vm, -1, SQUIRREL_MAX_DEPTH, false);
this->is_save_data_on_stack = true;
} else {
SaveEmpty();
this->engine->CrashOccurred();
}
} else {
ScriptLog::Warning("Save function is not implemented");
_script_sl_byte = 0;
SlObject(nullptr, _script_byte);
}
}
void ScriptInstance::Pause()
{
/* Suspend script. */
HSQUIRRELVM vm = this->engine->GetVM();
Squirrel::DecreaseOps(vm, _settings_game.script.script_max_opcode_till_suspend);
this->is_paused = true;
}
void ScriptInstance::Unpause()
{
this->is_paused = false;
}
bool ScriptInstance::IsPaused()
{
return this->is_paused;
}
/* static */ bool ScriptInstance::LoadObjects(ScriptData *data)
{
SlObject(nullptr, _script_byte);
switch (_script_sl_byte) {
case SQSL_INT: {
int64_t value;
SlCopy(&value, 1, IsSavegameVersionBefore(SLV_SCRIPT_INT64) ? SLE_FILE_I32 | SLE_VAR_I64 : SLE_INT64);
if (data != nullptr) data->push_back((SQInteger)value);
return true;
}
case SQSL_STRING: {
SlObject(nullptr, _script_byte);
static char buf[std::numeric_limits::max()];
SlCopy(buf, _script_sl_byte, SLE_CHAR);
if (data != nullptr) data->push_back(StrMakeValid(std::string_view(buf, _script_sl_byte)));
return true;
}
case SQSL_ARRAY:
case SQSL_TABLE: {
if (data != nullptr) data->push_back((SQSaveLoadType)_script_sl_byte);
while (LoadObjects(data));
return true;
}
case SQSL_BOOL: {
SlObject(nullptr, _script_byte);
if (data != nullptr) data->push_back((SQBool)(_script_sl_byte != 0));
return true;
}
case SQSL_NULL: {
if (data != nullptr) data->push_back((SQSaveLoadType)_script_sl_byte);
return true;
}
case SQSL_ARRAY_TABLE_END: {
if (data != nullptr) data->push_back((SQSaveLoadType)_script_sl_byte);
return false;
}
default: SlErrorCorrupt("Invalid script data type");
}
}
/* static */ bool ScriptInstance::LoadObjects(HSQUIRRELVM vm, ScriptData *data)
{
ScriptDataVariant value = data->front();
data->pop_front();
if (std::holds_alternative(value)) {
sq_pushinteger(vm, std::get(value));
return true;
}
if (std::holds_alternative(value)) {
sq_pushstring(vm, std::get(value), -1);
return true;
}
if (std::holds_alternative(value)) {
sq_pushbool(vm, std::get(value));
return true;
}
switch (std::get(value)) {
case SQSL_ARRAY: {
sq_newarray(vm, 0);
while (LoadObjects(vm, data)) {
sq_arrayappend(vm, -2);
/* The value is popped from the stack by squirrel. */
}
return true;
}
case SQSL_TABLE: {
sq_newtable(vm);
while (LoadObjects(vm, data)) {
LoadObjects(vm, data);
sq_rawset(vm, -3);
/* The key (-2) and value (-1) are popped from the stack by squirrel. */
}
return true;
}
case SQSL_NULL: {
sq_pushnull(vm);
return true;
}
case SQSL_ARRAY_TABLE_END: {
return false;
}
default: NOT_REACHED();
}
}
/* static */ void ScriptInstance::LoadEmpty()
{
SlObject(nullptr, _script_byte);
/* Check if there was anything saved at all. */
if (_script_sl_byte == 0) return;
LoadObjects(nullptr);
}
/* static */ ScriptInstance::ScriptData *ScriptInstance::Load(int version)
{
if (version == -1) {
LoadEmpty();
return nullptr;
}
SlObject(nullptr, _script_byte);
/* Check if there was anything saved at all. */
if (_script_sl_byte == 0) return nullptr;
ScriptData *data = new ScriptData();
data->push_back((SQInteger)version);
LoadObjects(data);
return data;
}
void ScriptInstance::LoadOnStack(ScriptData *data)
{
ScriptObject::ActiveInstance active(this);
if (this->IsDead() || data == nullptr) return;
HSQUIRRELVM vm = this->engine->GetVM();
ScriptDataVariant version = data->front();
data->pop_front();
SQInteger top = sq_gettop(vm);
try {
sq_pushinteger(vm, std::get(version));
LoadObjects(vm, data);
this->is_save_data_on_stack = true;
} catch (Script_FatalError &e) {
ScriptLog::Warning(fmt::format("Loading failed: {}", e.GetErrorMessage()));
/* Discard partially loaded savegame data and version. */
sq_settop(vm, top);
}
}
bool ScriptInstance::CallLoad()
{
HSQUIRRELVM vm = this->engine->GetVM();
/* Is there save data that we should load? */
if (!this->is_save_data_on_stack) return true;
/* Whatever happens, after CallLoad the savegame data is removed from the stack. */
this->is_save_data_on_stack = false;
if (!this->engine->MethodExists(*this->instance, "Load")) {
ScriptLog::Warning("Loading failed: there was data for the script to load, but the script does not have a Load() function.");
/* Pop the savegame data and version. */
sq_pop(vm, 2);
return true;
}
/* Go to the instance-root */
sq_pushobject(vm, *this->instance);
/* Find the function-name inside the script */
sq_pushstring(vm, "Load", -1);
/* Change the "Load" string in a function pointer */
sq_get(vm, -2);
/* Push the main instance as "this" object */
sq_pushobject(vm, *this->instance);
/* Push the version data and savegame data as arguments */
sq_push(vm, -5);
sq_push(vm, -5);
/* Call the script load function. sq_call removes the arguments (but not the
* function pointer) from the stack. */
if (SQ_FAILED(sq_call(vm, 3, SQFalse, SQFalse, MAX_SL_OPS))) return false;
/* Pop 1) The version, 2) the savegame data, 3) the object instance, 4) the function pointer. */
sq_pop(vm, 4);
return true;
}
SQInteger ScriptInstance::GetOpsTillSuspend()
{
return this->engine->GetOpsTillSuspend();
}
bool ScriptInstance::DoCommandCallback(const CommandCost &result, const CommandDataBuffer &data, CommandDataBuffer result_data, Commands cmd)
{
ScriptObject::ActiveInstance active(this);
if (!ScriptObject::CheckLastCommand(data, cmd)) {
Debug(script, 1, "DoCommandCallback terminating a script, last command does not match expected command");
return false;
}
ScriptObject::SetLastCommandRes(result.Succeeded());
ScriptObject::SetLastCommandResData(std::move(result_data));
if (result.Failed()) {
ScriptObject::SetLastError(ScriptError::StringToError(result.GetErrorMessage()));
} else {
ScriptObject::IncreaseDoCommandCosts(result.GetCost());
ScriptObject::SetLastCost(result.GetCost());
}
ScriptObject::SetLastCommand({}, CMD_END);
return true;
}
void ScriptInstance::InsertEvent(class ScriptEvent *event)
{
ScriptObject::ActiveInstance active(this);
ScriptEventController::InsertEvent(event);
}
size_t ScriptInstance::GetAllocatedMemory() const
{
if (this->engine == nullptr) return this->last_allocated_memory;
return this->engine->GetAllocatedMemory();
}
void ScriptInstance::ReleaseSQObject(HSQOBJECT *obj)
{
if (!this->in_shutdown) this->engine->ReleaseObject(obj);
}