LuaState Class Reference

#include <celx.h>

Collaboration diagram for LuaState:

List of all members.

Public Types
enum	IOMode { NoIO = 1, Asking = 2, IOAllowed = 4, IODenied = 8 }
Public Member Functions
bool	charEntered (const char *)
void	cleanup ()
bool	createThread ()
std::string	getErrorMessage ()
lua_State *	getState () const
double	getTime () const
bool	init (CelestiaCore *)
bool	isAlive () const
int	loadScript (const std::string &)
int	loadScript (std::istream &, const std::string &streamname)
	LuaState ()
void	requestIO ()
int	resume ()
bool	tick (double)
bool	timesliceExpired ()
	~LuaState ()
Public Attributes
int	screenshotCount
double	timeout
Private Attributes
bool	alive
lua_State *	costate
IOMode	ioMode
double	scriptAwakenTime
lua_State *	state
Timer *	timer

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Member Enumeration Documentation

enum LuaState::IOMode

Enumeration values: NoIO  Asking  IOAllowed  IODenied  Definition at line 53 of file celx.h. { NoIO = 1, Asking = 2, IOAllowed = 4, IODenied = 8 };

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Constructor & Destructor Documentation

LuaState::LuaState (   )

Definition at line 372 of file celx.cpp. References CreateTimer(), MaxTimeslice, screenshotCount, state, and timer. : timeout(MaxTimeslice), state(NULL), costate(NULL), alive(false), timer(NULL), scriptAwakenTime(0.1), ioMode(NoIO) { state = lua_open(); timer = CreateTimer(); screenshotCount = 0; }

LuaState::~LuaState (   )

Definition at line 386 of file celx.cpp. References costate, state, and timer. { delete timer; if (state != NULL) lua_close(state); #if 0 if (costate != NULL) lua_close(costate); #endif }

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Member Function Documentation

bool LuaState::charEntered (  const char *   )

Definition at line 594 of file celx.cpp. References Asking, costate, getAppCore(), CelestiaCore::getRenderer(), CelestiaCore::getTextEnterMode(), getTime(), IOAllowed, IODenied, ioMode, KbdCallback, NoErrors, Renderer::setRenderFlags(), CelestiaCore::setTextEnterMode(), CelestiaCore::showText(), and timeout. { if (ioMode == Asking && getTime() > timeout) { int stackTop = lua_gettop(costate); if (strcmp(c_p, "y") == 0) { lua_iolibopen(costate); ioMode = IOAllowed; } else { ioMode = IODenied; } CelestiaCore* appCore = getAppCore(costate, NoErrors); if (appCore == NULL) { cerr << "ERROR: appCore not found\n"; return true; } appCore->setTextEnterMode(appCore->getTextEnterMode() & ~CelestiaCore::KbPassToScript); appCore->showText("", 0, 0, 0, 0); // Restore renderflags: lua_pushstring(costate, "celestia-savedrenderflags"); lua_gettable(costate, LUA_REGISTRYINDEX); if (lua_isuserdata(costate, -1)) { int* savedrenderflags = static_cast<int*>(lua_touserdata(costate, -1)); appCore->getRenderer()->setRenderFlags(*savedrenderflags); // now delete entry: lua_pushstring(costate, "celestia-savedrenderflags"); lua_pushnil(costate); lua_settable(costate, LUA_REGISTRYINDEX); } else { cerr << "Oops, expected savedrenderflags to be userdata\n"; } lua_settop(costate,stackTop); return true; } int stack_top = lua_gettop(costate); bool result = true; lua_pushstring(costate, KbdCallback); lua_gettable(costate, LUA_GLOBALSINDEX); lua_pushstring(costate, c_p); timeout = getTime() + 1.0; if (lua_pcall(costate, 1, 1, 0) != 0) { cerr << "Error while executing keyboard-callback: " << lua_tostring(costate, -1) << "\n"; result = false; } else { if (lua_isboolean(costate, -1)) { result = static_cast<bool>(lua_toboolean(costate, -1)); } } // cleanup stack - is this necessary? lua_settop(costate, stack_top); return result; }

void LuaState::cleanup (   )

Definition at line 439 of file celx.cpp. References Asking, CleanupCallback, costate, getAppCore(), CelestiaCore::getRenderer(), getTime(), ioMode, NoErrors, Renderer::setRenderFlags(), state, and timeout. { if (ioMode == Asking) { // Restore renderflags: CelestiaCore* appCore = getAppCore(costate, NoErrors); if (appCore != NULL) { lua_pushstring(state, "celestia-savedrenderflags"); lua_gettable(state, LUA_REGISTRYINDEX); if (lua_isuserdata(state, -1)) { int* savedrenderflags = static_cast<int*>(lua_touserdata(state, -1)); appCore->getRenderer()->setRenderFlags(*savedrenderflags); // now delete entry: lua_pushstring(state, "celestia-savedrenderflags"); lua_pushnil(state); lua_settable(state, LUA_REGISTRYINDEX); } lua_pop(state,1); } } lua_pushstring(costate, CleanupCallback); lua_gettable(costate, LUA_GLOBALSINDEX); if (lua_isnil(costate, -1)) { return; } timeout = getTime() + 1.0; if (lua_pcall(costate, 0, 0, 0) != 0) { cerr << "Error while executing cleanup-callback: " << lua_tostring(costate, -1) << "\n"; } }

bool LuaState::createThread (   )

Definition at line 475 of file celx.cpp. References alive, checkTimeslice(), costate, and state. { // Initialize the coroutine which wraps the script if (!(lua_isfunction(state, -1) && !lua_iscfunction(state, -1))) { // Should never happen; we manually set up the stack in C++ assert(0); return false; } else { costate = lua_newthread(state); if (costate == NULL) return false; lua_sethook(costate, checkTimeslice, LUA_MASKCOUNT, 1000); lua_pushvalue(state, -2); lua_xmove(state, costate, 1); /* move function from L to NL */ alive = true; return true; } }

string LuaState::getErrorMessage (   )

Definition at line 498 of file celx.cpp. References state. { if (lua_gettop(state) > 0) { if (lua_isstring(state, -1)) return lua_tostring(state, -1); } return ""; }

lua_State * LuaState::getState (   )  const

Definition at line 397 of file celx.cpp. References state. Referenced by tick(). { return state; }

double LuaState::getTime (   )  const

Definition at line 403 of file celx.cpp. References Timer::getTime(), and timer. Referenced by celestia_getscripttime(), celestia_takescreenshot(), celscript_tick(), charEntered(), cleanup(), object_preloadtexture(), resume(), tick(), and timesliceExpired(). { return timer->getTime(); }

bool LuaState::init (  CelestiaCore *   )

Definition at line 4575 of file celx.cpp. References alerter, celestia_new(), CreateCelestiaMetaTable(), CreateCelscriptMetaTable(), CreateFrameMetaTable(), CreateObjectMetaTable(), CreateObserverMetaTable(), CreatePositionMetaTable(), CreateRotationMetaTable(), CreateVectorMetaTable(), KdeAlerter::fatalError(), initMaps(), KM_PER_LY, loadScript(), and state. { initMaps(); // Import the base and math libraries lua_baselibopen(state); lua_mathlibopen(state); lua_tablibopen(state); lua_strlibopen(state); // Add an easy to use wait function, so that script writers can // live in ignorance of coroutines. There will probably be a significant // library of useful functions that can be defined purely in Lua. // At that point, we'll want something a bit more robust than just // parsing the whole text of the library every time a script is launched if (loadScript("wait = function(x) coroutine.yield(x) end") != 0) return false; lua_pcall(state, 0, 0, 0); // execute it lua_pushstring(state, "KM_PER_MICROLY"); lua_pushnumber(state, (lua_Number)KM_PER_LY/1e6); lua_settable(state, LUA_GLOBALSINDEX); CreateObjectMetaTable(state); CreateObserverMetaTable(state); CreateCelestiaMetaTable(state); CreatePositionMetaTable(state); CreateVectorMetaTable(state); CreateRotationMetaTable(state); CreateFrameMetaTable(state); CreateCelscriptMetaTable(state); // Create the celestia object lua_pushstring(state, "celestia"); celestia_new(state, appCore); lua_settable(state, LUA_GLOBALSINDEX); // add reference to appCore in the registry lua_pushstring(state, "celestia-appcore"); lua_pushlightuserdata(state, static_cast<void*>(appCore)); lua_settable(state, LUA_REGISTRYINDEX); // add a reference to the LuaState-object in the registry lua_pushstring(state, "celestia-luastate"); lua_pushlightuserdata(state, static_cast<void*>(this)); lua_settable(state, LUA_REGISTRYINDEX); #if 0 lua_pushstring(state, "dofile"); lua_gettable(state, LUA_GLOBALSINDEX); // function "dofile" on stack lua_pushstring(state, "luainit.celx"); // parameter if (lua_pcall(state, 1, 0, 0) != 0) // execute it { CelestiaCore::Alerter* alerter = appCore->getAlerter(); // copy string?! const char* errorMessage = lua_tostring(state, -1); cout << errorMessage << '\n'; cout.flush(); alerter->fatalError(errorMessage); return false; } #endif return true; }

bool LuaState::isAlive (   )  const

Definition at line 552 of file celx.cpp. References alive. Referenced by tick(). { return alive; }

int LuaState::loadScript (  const std::string &   )

Definition at line 681 of file celx.cpp. References loadScript(). { #ifdef HAVE_SSTREAM istringstream in(s); #else istrstream in(s.c_str()); #endif return loadScript(in, "string"); }

int LuaState::loadScript (  std::istream &  , const std::string &  streamname )

Definition at line 659 of file celx.cpp. References ReadChunkInfo::buf, ReadChunkInfo::bufSize, ReadChunkInfo::in, readStreamChunk(), and state. Referenced by init(), and loadScript(). { char buf[4096]; ReadChunkInfo info; info.buf = buf; info.bufSize = sizeof(buf); info.in = &in; if (streamname != "string") { lua_pushstring(state, "celestia-scriptpath"); lua_pushstring(state, streamname.c_str()); lua_settable(state, LUA_REGISTRYINDEX); } int status = lua_load(state, readStreamChunk, &info, streamname.c_str()); if (status != 0) cout << "Error loading script: " << lua_tostring(state, -1) << '\n'; return status; }

void LuaState::requestIO (   )

Definition at line 852 of file celx.cpp. References AllErrors, Asking, costate, getAppCore(), CelestiaCore::getConfig(), IOAllowed, IODenied, ioMode, NoIO, CelestiaConfig::scriptSystemAccessPolicy, and state. Referenced by celestia_requestsystemaccess(). { // the script requested IO, set the mode // so we display the warning during tick // and can request keyboard. We can't do this now // because the script is still active and could // disable keyboard again. if (ioMode == NoIO) { CelestiaCore* appCore = getAppCore(state, AllErrors); string policy = appCore->getConfig()->scriptSystemAccessPolicy; if (policy == "allow") { //lua_iolibopen(costate); luaopen_io(costate); ioMode = IOAllowed; } else if (policy == "deny") { ioMode = IODenied; } else { ioMode = Asking; } } }

int LuaState::resume (   )

Definition at line 691 of file celx.cpp. References alerter, alive, Asking, auxresume(), costate, KdeAlerter::fatalError(), CelestiaCore::getAlerter(), getAppCore(), getTime(), ioMode, MaxTimeslice, state, and timeout. Referenced by tick(). { assert(costate != NULL); if (costate == NULL) return false; lua_State* co = lua_tothread(state, -1); //assert(co == costate); // co can be NULL after error (top stack is errorstring) if (co != costate) return false; timeout = getTime() + MaxTimeslice; int nArgs = auxresume(state, co, 0); if (nArgs < 0) { alive = false; const char* errorMessage = lua_tostring(state, -1); // This is a nasty and hopefully temporary hack . . . We continue // to resume the script until we get an error. The // 'cannot resume dead coroutine' error appears when there were // no other errors, and execution terminates normally. There // should be a better way to figure out whether the script ended // normally . . . if (strcmp(errorMessage, "cannot resume dead coroutine") != 0) { cout << "Error: " << errorMessage << '\n'; CelestiaCore* appCore = getAppCore(co); if (appCore != NULL) { CelestiaCore::Alerter* alerter = appCore->getAlerter(); alerter->fatalError(errorMessage); } } return 1; // just the error string } else { if (ioMode == Asking) { // timeout now is used to first only display warning, and 1s // later allow response to avoid accidental activation timeout = getTime() + 1.0; } return nArgs; // arguments from yield } }

bool LuaState::tick (  double   )

Definition at line 763 of file celx.cpp. References Asking, costate, getAppCore(), CelestiaCore::getRenderer(), Renderer::getRenderFlags(), getState(), CelestiaCore::getTextEnterMode(), getTime(), ioMode, isAlive(), NoErrors, resume(), scriptAwakenTime, Renderer::setRenderFlags(), CelestiaCore::setTextEnterMode(), CelestiaCore::showText(), state, and timeout. { // Due to the way CelestiaCore::tick is called (at least for KDE), // this method may be entered a second time when we show the error-alerter // Workaround: check if we are alive, return true(!) when we aren't anymore // this way the script isn't deleted after the second enter, but only // when we return from the first enter. OMG. // better Solution: defer showing the error-alterter to CelestiaCore, using // getErrorMessage() if (!isAlive()) return false; if (ioMode == Asking) { CelestiaCore* appCore = getAppCore(costate, NoErrors); if (appCore == NULL) { cerr << "ERROR: appCore not found\n"; return true; } lua_pushstring(state, "celestia-savedrenderflags"); lua_gettable(state, LUA_REGISTRYINDEX); if (lua_isnil(state, -1)) { lua_pushstring(state, "celestia-savedrenderflags"); int* savedrenderflags = static_cast<int*>(lua_newuserdata(state, sizeof(int))); *savedrenderflags = appCore->getRenderer()->getRenderFlags(); lua_settable(state, LUA_REGISTRYINDEX); appCore->getRenderer()->setRenderFlags(0); } // now pop result of gettable lua_pop(state, 1); if (getTime() > timeout) { appCore->showText("WARNING:\n\nThis script requests permission to read/write files\n" "and execute external programs. Allowing this can be\n" "dangerous.\n" "Do you trust the script and want to allow this?\n\n" "y = yes, ESC = cancel script, any other key = no", 0, 0, -15, 5, 5); appCore->setTextEnterMode(appCore->getTextEnterMode() | CelestiaCore::KbPassToScript); } else { appCore->showText("WARNING:\n\nThis script requests permission to read/write files\n" "and execute external programs. Allowing this can be\n" "dangerous.\n" "Do you trust the script and want to allow this?", 0, 0, -15, 5, 5); appCore->setTextEnterMode(appCore->getTextEnterMode() & ~CelestiaCore::KbPassToScript); } return false; } if (dt == 0 || scriptAwakenTime > getTime()) return false; int nArgs = resume(); if (!isAlive()) { // The script is complete return true; } else { // The script has returned control to us, but it is not completed. lua_State* state = getState(); // The values on the stack indicate what event will wake up the // script. For now, we just support wait() double delay; if (nArgs == 1 && lua_isnumber(state, -1)) delay = lua_tonumber(state, -1); else delay = 0.0; scriptAwakenTime = getTime() + delay; // Clean up the stack lua_pop(state, nArgs); return false; } }

bool LuaState::timesliceExpired (   )

Definition at line 509 of file celx.cpp. References checkTimeslice(), costate, getTime(), and timeout. Referenced by checkTimeslice(). { if (timeout < getTime()) { // timeslice expired, make every instruction (including pcall) fail: lua_sethook(costate, checkTimeslice, LUA_MASKCOUNT, 1); return true; } else { return false; } }

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Member Data Documentation

bool LuaState::alive [private]

Definition at line 63 of file celx.h. Referenced by createThread(), isAlive(), and resume().

lua_State* LuaState::costate [private]

Definition at line 62 of file celx.h. Referenced by charEntered(), cleanup(), createThread(), requestIO(), resume(), tick(), timesliceExpired(), and ~LuaState().

IOMode LuaState::ioMode [private]

Definition at line 66 of file celx.h. Referenced by charEntered(), cleanup(), requestIO(), resume(), and tick().

int LuaState::screenshotCount

Definition at line 50 of file celx.h. Referenced by celestia_takescreenshot(), and LuaState().

double LuaState::scriptAwakenTime [private]

Definition at line 65 of file celx.h. Referenced by tick().

lua_State* LuaState::state [private]

Definition at line 61 of file celx.h. Referenced by cleanup(), createThread(), getErrorMessage(), getState(), init(), loadScript(), LuaState(), requestIO(), resume(), tick(), and ~LuaState().

double LuaState::timeout

Definition at line 51 of file celx.h. Referenced by celestia_takescreenshot(), charEntered(), cleanup(), object_preloadtexture(), resume(), tick(), and timesliceExpired().

Timer* LuaState::timer [private]

Definition at line 64 of file celx.h. Referenced by getTime(), LuaState(), and ~LuaState().

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The documentation for this class was generated from the following files:

• src/celestia/celx.h
• src/celestia/celx.cpp

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