effil/src/cpp/threading.cpp
2017-09-29 00:22:15 +03:00

329 lines
9.5 KiB
C++

#include "threading.h"
#include "stored-object.h"
#include "notifier.h"
#include "spin-mutex.h"
#include "utils.h"
#include <thread>
#include <sstream>
namespace effil {
namespace {
// Doesn't inherit std::exception
// to prevent from catching this exception third party lua C++ libs
class LuaHookStopException {};
enum class Status {
Running,
Paused,
Canceled,
Completed,
Failed
};
bool isFinishStatus(Status stat) {
return stat == Status::Canceled || stat == Status::Completed || stat == Status::Failed;
}
std::string statusToString(Status status) {
switch (status) {
case Status::Running:
return "running";
case Status::Paused:
return "paused";
case Status::Canceled:
return "canceled";
case Status::Completed:
return "completed";
case Status::Failed:
return "failed";
}
assert(false);
return "unknown";
}
enum class Command {
Run,
Cancel,
Pause
};
} // namespace
class ThreadHandle {
public:
ThreadHandle()
: status_(Status::Running)
, command_(Command::Run)
, lua_(std::make_unique<sol::state>()) {
luaL_openlibs(*lua_);
}
Command command() const { return command_; }
void putCommand(Command cmd) {
std::unique_lock<std::mutex> lock(stateLock_);
if (isFinishStatus(status_))
return;
command_ = cmd;
statusNotifier_.reset();
commandNotifier_.notify();
}
void changeStatus(Status stat) {
std::unique_lock<std::mutex> lock(stateLock_);
status_ = stat;
commandNotifier_.reset();
statusNotifier_.notify();
if (isFinishStatus(stat))
completionNotifier_.notify();
}
template <typename T>
Status waitForStatusChange(const sol::optional<T>& time) {
if (time)
statusNotifier_.waitFor(*time);
else
statusNotifier_.wait();
return status_;
}
template <typename T>
Command waitForCommandChange(const sol::optional<T>& time) {
if (time)
commandNotifier_.waitFor(*time);
else
commandNotifier_.wait();
return command_;
}
template <typename T>
bool waitForCompletion(const sol::optional<T>& time) {
if (time) {
return completionNotifier_.waitFor(*time);
}
else {
completionNotifier_.wait();
return true;
}
}
sol::state& lua() {
assert(lua_);
return *lua_;
}
void destroyLua() { lua_.reset(); }
Status status() { return status_; }
StoredArray& result() { return result_; }
private:
Status status_;
Command command_;
Notifier statusNotifier_;
Notifier commandNotifier_;
Notifier completionNotifier_;
std::mutex stateLock_;
StoredArray result_;
std::unique_ptr<sol::state> lua_;
};
namespace {
const sol::optional<std::chrono::milliseconds> NO_TIMEOUT;
static thread_local ThreadHandle* thisThreadHandle = nullptr;
void luaHook(lua_State*, lua_Debug*) {
assert(thisThreadHandle);
switch (thisThreadHandle->command()) {
case Command::Run:
break;
case Command::Cancel:
throw LuaHookStopException();
case Command::Pause: {
thisThreadHandle->changeStatus(Status::Paused);
Command cmd;
do {
cmd = thisThreadHandle->waitForCommandChange(NO_TIMEOUT);
} while(cmd != Command::Run && cmd != Command::Cancel);
if (cmd == Command::Run)
thisThreadHandle->changeStatus(Status::Running);
else
throw LuaHookStopException();
break;
}
}
}
void runThread(std::shared_ptr<ThreadHandle> handle,
std::string strFunction,
effil::StoredArray arguments) {
assert(handle);
thisThreadHandle = handle.get();
try {
{
ScopeGuard reportComplete([handle, &arguments](){
DEBUG << "Finished " << std::endl;
// Let's destroy accociated state
// to release all resources as soon as possible
arguments.clear();
handle->destroyLua();
});
sol::function userFuncObj = loadString(handle->lua(), strFunction);
sol::function_result results = userFuncObj(std::move(arguments));
(void)results; // just leave all returns on the stack
sol::variadic_args args(handle->lua(), -lua_gettop(handle->lua()));
for (const auto& iter : args) {
StoredObject store = createStoredObject(iter.get<sol::object>());
handle->result().emplace_back(std::move(store));
}
}
handle->changeStatus(Status::Completed);
} catch (const LuaHookStopException&) {
handle->changeStatus(Status::Canceled);
} catch (const sol::error& err) {
DEBUG << "Failed with msg: " << err.what() << std::endl;
handle->result().emplace_back(createStoredObject(err.what()));
handle->changeStatus(Status::Failed);
}
}
} // namespace
std::string threadId() {
std::stringstream ss;
ss << std::this_thread::get_id();
return ss.str();
}
void yield() {
if (thisThreadHandle)
luaHook(nullptr, nullptr);
std::this_thread::yield();
}
void sleep(const sol::stack_object& duration, const sol::stack_object& metric) {
if (duration.valid()) {
REQUIRE(duration.get_type() == sol::type::number) << "bad argument #1 to 'effil.sleep' (number expected, got " << luaTypename(duration) << ")";
if (metric.valid())
REQUIRE(metric.get_type() == sol::type::string) << "bad argument #2 to 'effil.sleep' (string expected, got " << luaTypename(metric) << ")";
try {
std::this_thread::sleep_for(fromLuaTime(duration.as<int>(), metric.valid() ? metric.as<std::string>() : sol::optional<std::string>()));
} RETHROW_WITH_PREFIX("effil.sleep");
}
else {
yield();
}
}
Thread::Thread(const std::string& path,
const std::string& cpath,
int step,
const sol::function& function,
const sol::variadic_args& variadicArgs)
: handle_(std::make_shared<ThreadHandle>()) {
handle_->lua()["package"]["path"] = path;
handle_->lua()["package"]["cpath"] = cpath;
handle_->lua().script("require 'effil'");
if (step != 0)
lua_sethook(handle_->lua(), luaHook, LUA_MASKCOUNT, step);
std::string strFunction = dumpFunction(function);
effil::StoredArray arguments;
try {
for (const auto& arg : variadicArgs) {
arguments.emplace_back(createStoredObject(arg.get<sol::object>()));
}
} RETHROW_WITH_PREFIX("effil.thread");
std::thread thr(&runThread,
handle_,
std::move(strFunction),
std::move(arguments));
DEBUG << "Created " << thr.get_id() << std::endl;
thr.detach();
}
void Thread::exportAPI(sol::state_view& lua) {
sol::usertype<Thread> type(
"new", sol::no_constructor,
"get", &Thread::get,
"wait", &Thread::wait,
"cancel", &Thread::cancel,
"pause", &Thread::pause,
"resume", &Thread::resume,
"status", &Thread::status);
sol::stack::push(lua, type);
sol::stack::pop<sol::object>(lua);
}
std::pair<sol::object, sol::object> Thread::status(const sol::this_state& lua) {
sol::object luaStatus = sol::make_object(lua, statusToString(handle_->status()));
if (handle_->status() == Status::Failed) {
assert(!handle_->result().empty());
return std::make_pair(luaStatus, handle_->result()[0]->unpack(lua));
} else {
return std::make_pair(luaStatus, sol::nil);
}
}
sol::optional<std::chrono::milliseconds> toOptionalTime(const sol::optional<int>& duration,
const sol::optional<std::string>& period) {
if (duration)
return fromLuaTime(*duration, period);
else
return sol::optional<std::chrono::milliseconds>();
}
std::pair<sol::object, sol::object> Thread::wait(const sol::this_state& lua,
const sol::optional<int>& duration,
const sol::optional<std::string>& period) {
handle_->waitForCompletion(toOptionalTime(duration, period));
return status(lua);
}
StoredArray Thread::get(const sol::optional<int>& duration,
const sol::optional<std::string>& period) {
if (handle_->waitForCompletion(toOptionalTime(duration, period)) && handle_->status() == Status::Completed)
return handle_->result();
else
return StoredArray();
}
bool Thread::cancel(const sol::this_state&,
const sol::optional<int>& duration,
const sol::optional<std::string>& period) {
handle_->putCommand(Command::Cancel);
Status status = handle_->waitForStatusChange(toOptionalTime(duration, period));
return isFinishStatus(status);
}
bool Thread::pause(const sol::this_state&,
const sol::optional<int>& duration,
const sol::optional<std::string>& period) {
handle_->putCommand(Command::Pause);
Status status = handle_->waitForStatusChange(toOptionalTime(duration, period));
return status == Status::Paused;
}
void Thread::resume() {
handle_->putCommand(Command::Run);
}
} // effil