13 #include <simgear/nasal/nasal.h>
14 #include <simgear/props/props.hxx>
15 #include <simgear/math/sg_random.h>
16 #include <simgear/misc/sg_path.hxx>
17 #include <simgear/misc/interpolator.hxx>
18 #include <simgear/structure/commands.hxx>
20 #include <Main/globals.hxx>
21 #include <Main/fg_props.hxx>
23 #include "NasalSys.hxx"
25 static FGNasalSys* nasalSys = 0;
28 // Read and return file contents in a single buffer. Note use of
29 // stat() to get the file size. This is a win32 function, believe it
30 // or not. :) Note the REALLY IMPORTANT use of the "b" flag to fopen.
31 // Text mode brain damage will kill us if we're trying to do bytewise
33 static char* readfile(const char* file, int* lenOut)
36 if(stat(file, &data) != 0) return 0;
37 FILE* f = fopen(file, "rb");
39 char* buf = new char[data.st_size];
40 *lenOut = fread(buf, 1, data.st_size, f);
42 if(*lenOut != data.st_size) {
43 // Shouldn't happen, but warn anyway since it represents a
44 // platform bug and not a typical runtime error (missing file,
46 SG_LOG(SG_NASAL, SG_ALERT,
47 "ERROR in Nasal initialization: " <<
48 "short count returned from fread() of " << file <<
49 ". Check your C library!");
56 FGNasalSys::FGNasalSys()
62 _nextGCKey = 0; // Any value will do
64 _purgeListeners = false;
67 // Does a naCall() in a new context. Wrapped here to make lock
68 // tracking easier. Extension functions are called with the lock, but
69 // we have to release it before making a new naCall(). So rather than
70 // drop the lock in every extension function that might call back into
71 // Nasal, we keep a stack depth counter here and only unlock/lock
72 // around the naCall if it isn't the first one.
73 naRef FGNasalSys::call(naRef code, naRef locals)
75 naContext ctx = naNewContext();
76 if(_callCount) naModUnlock();
78 naRef result = naCall(ctx, code, 0, 0, naNil(), locals);
82 if(_callCount) naModLock();
87 FGNasalSys::~FGNasalSys()
90 map<int, FGNasalListener *>::iterator it, end = _listener.end();
91 for(it = _listener.begin(); it != end; ++it)
94 naFreeContext(_context);
98 bool FGNasalSys::parseAndRun(const char* sourceCode)
100 naRef code = parse("FGNasalSys::parseAndRun()", sourceCode,
108 FGNasalScript* FGNasalSys::parseScript(const char* src, const char* name)
110 FGNasalScript* script = new FGNasalScript();
111 script->_gcKey = -1; // important, if we delete it on a parse
112 script->_nas = this; // error, don't clobber a real handle!
116 sprintf(buf, "FGNasalScript@%p", script);
120 script->_code = parse(name, src, strlen(src));
121 if(naIsNil(script->_code)) {
126 script->_gcKey = gcSave(script->_code);
130 // Utility. Sets a named key in a hash by C string, rather than nasal
132 void FGNasalSys::hashset(naRef hash, const char* key, naRef val)
134 naRef s = naNewString(_context);
135 naStr_fromdata(s, (char*)key, strlen(key));
136 naHash_set(hash, s, val);
139 // The get/setprop functions accept a *list* of strings and walk
140 // through the property tree with them to find the appropriate node.
141 // This allows a Nasal object to hold onto a property path and use it
142 // like a node object, e.g. setprop(ObjRoot, "size-parsecs", 2.02). This
143 // is the utility function that walks the property tree.
144 // Future enhancement: support integer arguments to specify array
146 static SGPropertyNode* findnode(naContext c, naRef* vec, int len)
148 SGPropertyNode* p = globals->get_props();
150 for(int i=0; i<len; i++) {
152 if(!naIsString(a)) return 0;
153 p = p->getNode(naStr_data(a));
156 } catch (const string& err) {
157 naRuntimeError(c, (char *)err.c_str());
163 // getprop() extension function. Concatenates its string arguments as
164 // property names and returns the value of the specified property. Or
165 // nil if it doesn't exist.
166 static naRef f_getprop(naContext c, naRef me, int argc, naRef* args)
168 const SGPropertyNode* p = findnode(c, args, argc);
169 if(!p) return naNil();
171 switch(p->getType()) {
172 case SGPropertyNode::BOOL: case SGPropertyNode::INT:
173 case SGPropertyNode::LONG: case SGPropertyNode::FLOAT:
174 case SGPropertyNode::DOUBLE:
175 return naNum(p->getDoubleValue());
177 case SGPropertyNode::STRING:
178 case SGPropertyNode::UNSPECIFIED:
180 naRef nastr = naNewString(c);
181 const char* val = p->getStringValue();
182 naStr_fromdata(nastr, (char*)val, strlen(val));
185 case SGPropertyNode::ALIAS: // <--- FIXME, recurse?
191 // setprop() extension function. Concatenates its string arguments as
192 // property names and sets the value of the specified property to the
194 static naRef f_setprop(naContext c, naRef me, int argc, naRef* args)
197 char buf[BUFLEN + 1];
201 for(int i=0; i<argc-1; i++) {
202 naRef s = naStringValue(c, args[i]);
203 if(naIsNil(s)) return naNil();
204 strncpy(p, naStr_data(s), buflen);
206 buflen = BUFLEN - (p - buf);
207 if(i < (argc-2) && buflen > 0) {
213 SGPropertyNode* props = globals->get_props();
214 naRef val = args[argc-1];
216 if(naIsString(val)) props->setStringValue(buf, naStr_data(val));
218 naRef n = naNumValue(val);
220 naRuntimeError(c, "setprop() value is not string or number");
221 props->setDoubleValue(buf, n.num);
223 } catch (const string& err) {
224 naRuntimeError(c, (char *)err.c_str());
230 // print() extension function. Concatenates and prints its arguments
231 // to the FlightGear log. Uses the highest log level (SG_ALERT), to
232 // make sure it appears. Is there better way to do this?
233 static naRef f_print(naContext c, naRef me, int argc, naRef* args)
237 for(int i=0; i<n; i++) {
238 naRef s = naStringValue(c, args[i]);
239 if(naIsNil(s)) continue;
240 buf += naStr_data(s);
242 SG_LOG(SG_GENERAL, SG_ALERT, buf);
243 return naNum(buf.length());
246 // fgcommand() extension function. Executes a named command via the
247 // FlightGear command manager. Takes a single property node name as
249 static naRef f_fgcommand(naContext c, naRef me, int argc, naRef* args)
251 if(argc < 2 || !naIsString(args[0]) || !naIsGhost(args[1]))
252 naRuntimeError(c, "bad arguments to fgcommand()");
253 naRef cmd = args[0], props = args[1];
254 SGPropertyNode_ptr* node = (SGPropertyNode_ptr*)naGhost_ptr(props);
255 return naNum(globals->get_commands()->execute(naStr_data(cmd), *node));
258 // settimer(func, dt, simtime) extension function. Falls through to
259 // FGNasalSys::setTimer(). See there for docs.
260 static naRef f_settimer(naContext c, naRef me, int argc, naRef* args)
262 nasalSys->setTimer(c, argc, args);
266 // setlistener(func, property, bool) extension function. Falls through to
267 // FGNasalSys::setListener(). See there for docs.
268 static naRef f_setlistener(naContext c, naRef me, int argc, naRef* args)
270 return nasalSys->setListener(c, argc, args);
273 // removelistener(int) extension function. Falls through to
274 // FGNasalSys::removeListener(). See there for docs.
275 static naRef f_removelistener(naContext c, naRef me, int argc, naRef* args)
277 return nasalSys->removeListener(c, argc, args);
280 // Returns a ghost handle to the argument to the currently executing
282 static naRef f_cmdarg(naContext c, naRef me, int argc, naRef* args)
284 return nasalSys->cmdArgGhost();
287 // Sets up a property interpolation. The first argument is either a
288 // ghost (SGPropertyNode_ptr*) or a string (global property path) to
289 // interpolate. The second argument is a vector of pairs of
290 // value/delta numbers.
291 static naRef f_interpolate(naContext c, naRef me, int argc, naRef* args)
293 SGPropertyNode* node;
294 naRef prop = argc > 0 ? args[0] : naNil();
295 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
296 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
299 naRef curve = argc > 1 ? args[1] : naNil();
300 if(!naIsVector(curve)) return naNil();
301 int nPoints = naVec_size(curve) / 2;
302 double* values = new double[nPoints];
303 double* deltas = new double[nPoints];
304 for(int i=0; i<nPoints; i++) {
305 values[i] = naNumValue(naVec_get(curve, 2*i)).num;
306 deltas[i] = naNumValue(naVec_get(curve, 2*i+1)).num;
309 ((SGInterpolator*)globals->get_subsystem_mgr()
310 ->get_group(SGSubsystemMgr::INIT)->get_subsystem("interpolator"))
311 ->interpolate(node, nPoints, values, deltas);
316 // This is a better RNG than the one in the default Nasal distribution
317 // (which is based on the C library rand() implementation). It will
319 static naRef f_rand(naContext c, naRef me, int argc, naRef* args)
321 return naNum(sg_random());
324 static naRef f_srand(naContext c, naRef me, int argc, naRef* args)
330 // Return an array listing of all files in a directory
331 static naRef f_directory(naContext c, naRef me, int argc, naRef* args)
333 if(argc != 1 || !naIsString(args[0]))
334 naRuntimeError(c, "bad arguments to directory()");
335 naRef ldir = args[0];
336 ulDir* dir = ulOpenDir(naStr_data(args[0]));
337 if(!dir) return naNil();
338 naRef result = naNewVector(c);
340 while((dent = ulReadDir(dir)))
341 naVec_append(result, naStr_fromdata(naNewString(c), dent->d_name,
342 strlen(dent->d_name)));
347 // Table of extension functions. Terminate with zeros.
348 static struct { char* name; naCFunction func; } funcs[] = {
349 { "getprop", f_getprop },
350 { "setprop", f_setprop },
351 { "print", f_print },
352 { "_fgcommand", f_fgcommand },
353 { "settimer", f_settimer },
354 { "_setlistener", f_setlistener },
355 { "removelistener", f_removelistener },
356 { "_cmdarg", f_cmdarg },
357 { "_interpolate", f_interpolate },
359 { "srand", f_srand },
360 { "directory", f_directory },
364 naRef FGNasalSys::cmdArgGhost()
366 return propNodeGhost(_cmdArg);
369 void FGNasalSys::init()
373 _context = naNewContext();
375 // Start with globals. Add it to itself as a recursive
376 // sub-reference under the name "globals". This gives client-code
377 // write access to the namespace if someone wants to do something
379 _globals = naInit_std(_context);
380 naSave(_context, _globals);
381 hashset(_globals, "globals", _globals);
383 hashset(_globals, "math", naInit_math(_context));
384 hashset(_globals, "bits", naInit_bits(_context));
385 hashset(_globals, "io", naInit_io(_context));
386 hashset(_globals, "thread", naInit_thread(_context));
387 hashset(_globals, "utf8", naInit_utf8(_context));
389 // Add our custom extension functions:
390 for(i=0; funcs[i].name; i++)
391 hashset(_globals, funcs[i].name,
392 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
394 // And our SGPropertyNode wrapper
395 hashset(_globals, "props", genPropsModule());
397 // Make a "__gcsave" hash to hold the naRef objects which get
398 // passed to handles outside the interpreter (to protect them from
399 // begin garbage-collected).
400 _gcHash = naNewHash(_context);
401 hashset(_globals, "__gcsave", _gcHash);
403 // Now load the various source files in the Nasal directory
404 SGPath p(globals->get_fg_root());
407 ulDir* dir = ulOpenDir(p.c_str());
408 while(dir && (dent = ulReadDir(dir)) != 0) {
410 fullpath.append(dent->d_name);
411 SGPath file(dent->d_name);
412 if(file.extension() != "nas") continue;
413 loadModule(fullpath, file.base().c_str());
417 // set signal and remove node to avoid restoring at reinit
418 const char *s = "nasal-dir-initialized";
419 SGPropertyNode *signal = fgGetNode("/sim/signals", true);
420 signal->setBoolValue(s, true);
421 signal->removeChildren(s);
423 // Pull scripts out of the property tree, too
424 loadPropertyScripts();
427 void FGNasalSys::update(double)
429 if(_purgeListeners) {
430 _purgeListeners = false;
431 map<int, FGNasalListener *>::iterator it;
432 for(it = _listener.begin(); it != _listener.end();) {
433 FGNasalListener *nl = it->second;
435 _listener.erase(it++);
444 // Loads the scripts found under /nasal in the global tree
445 void FGNasalSys::loadPropertyScripts()
447 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
450 for(int i=0; i<nasal->nChildren(); i++) {
451 SGPropertyNode* n = nasal->getChild(i);
453 const char* module = n->getName();
454 if(n->hasChild("module"))
455 module = n->getStringValue("module");
457 // allow multiple files to be specified within in a single
461 bool file_specified = false;
462 while ( (fn = n->getChild("file", j)) != NULL ) {
463 file_specified = true;
464 const char* file = fn->getStringValue();
465 SGPath p(globals->get_fg_root());
467 loadModule(p, module);
471 // Old code which only allowed a single file to be specified per module
473 const char* file = n->getStringValue("file");
474 if(!n->hasChild("file")) file = 0; // Hrm...
476 SGPath p(globals->get_fg_root());
478 loadModule(p, module);
482 const char* src = n->getStringValue("script");
483 if(!n->hasChild("script")) src = 0; // Hrm...
485 createModule(module, n->getPath(), src, strlen(src));
487 if(!file_specified && !src)
488 SG_LOG(SG_NASAL, SG_ALERT, "Nasal error: " <<
489 "no <file> or <script> defined in " <<
490 "/nasal/" << module);
494 // Logs a runtime error, with stack trace, to the FlightGear log stream
495 void FGNasalSys::logError(naContext context)
497 SG_LOG(SG_NASAL, SG_ALERT,
498 "Nasal runtime error: " << naGetError(context));
499 SG_LOG(SG_NASAL, SG_ALERT,
500 " at " << naStr_data(naGetSourceFile(context, 0)) <<
501 ", line " << naGetLine(context, 0));
502 for(int i=1; i<naStackDepth(context); i++)
503 SG_LOG(SG_NASAL, SG_ALERT,
504 " called from: " << naStr_data(naGetSourceFile(context, i)) <<
505 ", line " << naGetLine(context, i));
508 // Reads a script file, executes it, and places the resulting
509 // namespace into the global namespace under the specified module
511 void FGNasalSys::loadModule(SGPath file, const char* module)
514 char* buf = readfile(file.c_str(), &len);
516 SG_LOG(SG_NASAL, SG_ALERT,
517 "Nasal error: could not read script file " << file.c_str()
518 << " into module " << module);
522 createModule(module, file.c_str(), buf, len);
526 // Parse and run. Save the local variables namespace, as it will
527 // become a sub-object of globals. The optional "arg" argument can be
528 // used to pass an associated property node to the module, which can then
529 // be accessed via cmdarg(). (This is, for example, used by XML dialogs.)
530 void FGNasalSys::createModule(const char* moduleName, const char* fileName,
531 const char* src, int len, const SGPropertyNode* arg)
533 naRef code = parse(fileName, src, len);
537 // See if we already have a module hash to use. This allows the
538 // user to, for example, add functions to the built-in math
539 // module. Make a new one if necessary.
541 naRef modname = naNewString(_context);
542 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
543 if(!naHash_get(_globals, modname, &locals))
544 locals = naNewHash(_context);
546 _cmdArg = (SGPropertyNode*)arg;
549 hashset(_globals, moduleName, locals);
552 void FGNasalSys::deleteModule(const char* moduleName)
554 naRef modname = naNewString(_context);
555 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
556 naHash_delete(_globals, modname);
559 naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
562 naRef srcfile = naNewString(_context);
563 naStr_fromdata(srcfile, (char*)filename, strlen(filename));
564 naRef code = naParseCode(_context, srcfile, 1, (char*)buf, len, &errLine);
566 SG_LOG(SG_NASAL, SG_ALERT,
567 "Nasal parse error: " << naGetError(_context) <<
568 " in "<< filename <<", line " << errLine);
572 // Bind to the global namespace before returning
573 return naBindFunction(_context, code, _globals);
576 bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
578 const char* nasal = arg->getStringValue("script");
579 const char* moduleName = arg->getStringValue("module");
580 naRef code = parse(arg->getPath(true), nasal, strlen(nasal));
581 if(naIsNil(code)) return false;
583 // Commands can be run "in" a module. Make sure that module
584 // exists, and set it up as the local variables hash for the
586 naRef locals = naNil();
588 naRef modname = naNewString(_context);
589 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
590 if(!naHash_get(_globals, modname, &locals)) {
591 locals = naNewHash(_context);
592 naHash_set(_globals, modname, locals);
596 // Cache this command's argument for inspection via cmdarg(). For
597 // performance reasons, we won't bother with it if the invoked
598 // code doesn't need it.
599 _cmdArg = (SGPropertyNode*)arg;
605 // settimer(func, dt, simtime) extension function. The first argument
606 // is a Nasal function to call, the second is a delta time (from now),
607 // in seconds. The third, if present, is a boolean value indicating
608 // that "real world" time (rather than simulator time) is to be used.
610 // Implementation note: the FGTimer objects don't live inside the
611 // garbage collector, so the Nasal handler functions have to be
612 // "saved" somehow lest they be inadvertently cleaned. In this case,
613 // they are inserted into a globals.__gcsave hash and removed on
615 void FGNasalSys::setTimer(naContext c, int argc, naRef* args)
617 // Extract the handler, delta, and simtime arguments:
618 naRef handler = argc > 0 ? args[0] : naNil();
619 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler))) {
620 naRuntimeError(c, "settimer() with invalid function argument");
624 naRef delta = argc > 1 ? args[1] : naNil();
626 naRuntimeError(c, "settimer() with invalid time argument");
630 bool simtime = (argc > 2 && naTrue(args[2])) ? false : true;
632 // Generate and register a C++ timer handler
633 NasalTimer* t = new NasalTimer;
634 t->handler = handler;
635 t->gcKey = gcSave(handler);
638 globals->get_event_mgr()->addEvent("NasalTimer",
639 t, &NasalTimer::timerExpired,
643 void FGNasalSys::handleTimer(NasalTimer* t)
645 call(t->handler, naNil());
649 int FGNasalSys::gcSave(naRef r)
651 int key = _nextGCKey++;
652 naHash_set(_gcHash, naNum(key), r);
656 void FGNasalSys::gcRelease(int key)
658 naHash_delete(_gcHash, naNum(key));
661 void FGNasalSys::NasalTimer::timerExpired()
663 nasal->handleTimer(this);
667 int FGNasalSys::_listenerId = 0;
669 // setlistener(property, func, bool) extension function. The first argument
670 // is either a ghost (SGPropertyNode_ptr*) or a string (global property
671 // path), the second is a Nasal function, the optional third one a bool.
672 // If the bool is true, then the listener is executed initially. The
673 // setlistener() function returns a unique id number, that can be used
674 // as argument to the removelistener() function.
675 naRef FGNasalSys::setListener(naContext c, int argc, naRef* args)
677 SGPropertyNode_ptr node;
678 naRef prop = argc > 0 ? args[0] : naNil();
679 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
680 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
682 naRuntimeError(c, "setlistener() with invalid property argument");
687 SG_LOG(SG_NASAL, SG_DEBUG, "Attaching listener to tied property " <<
690 naRef handler = argc > 1 ? args[1] : naNil();
691 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler))) {
692 naRuntimeError(c, "setlistener() with invalid function argument");
696 bool initial = argc > 2 && naTrue(args[2]);
698 FGNasalListener *nl = new FGNasalListener(node, handler, this,
699 gcSave(handler), _listenerId);
700 node->addChangeListener(nl, initial);
702 _listener[_listenerId] = nl;
703 return naNum(_listenerId++);
706 // removelistener(int) extension function. The argument is the id of
707 // a listener as returned by the setlistener() function.
708 naRef FGNasalSys::removeListener(naContext c, int argc, naRef* args)
710 naRef id = argc > 0 ? args[0] : naNil();
711 map<int, FGNasalListener *>::iterator it = _listener.find(int(id.num));
713 if(!naIsNum(id) || it == _listener.end() || it->second->_dead) {
714 naRuntimeError(c, "removelistener() with invalid listener id");
718 FGNasalListener *nl = it->second;
721 _purgeListeners = true;
727 return naNum(_listener.size());
732 // FGNasalListener class.
734 FGNasalListener::FGNasalListener(SGPropertyNode_ptr node, naRef handler,
735 FGNasalSys* nasal, int key, int id) :
746 FGNasalListener::~FGNasalListener()
748 _node->removeChangeListener(this);
749 _nas->gcRelease(_gcKey);
752 void FGNasalListener::valueChanged(SGPropertyNode* node)
754 // drop recursive listener calls
758 SG_LOG(SG_NASAL, SG_DEBUG, "trigger listener #" << _id);
760 _nas->_cmdArg = node;
761 _nas->call(_handler, naNil());
768 // FGNasalModelData class. If sgLoad3DModel() is called with a pointer to
769 // such a class, then it lets modelLoaded() run the <load> script, and the
770 // destructor the <unload> script. The latter happens when the model branch
771 // is removed from the scene graph.
773 void FGNasalModelData::modelLoaded(const string& path, SGPropertyNode *prop,
776 SGPropertyNode *n = prop->getNode("nasal"), *load;
780 load = n->getNode("load");
781 _unload = n->getNode("unload");
782 if(!load && !_unload)
786 const char *s = load ? load->getStringValue() : "";
787 nasalSys->createModule(_module.c_str(), _module.c_str(), s, strlen(s), _props);
790 FGNasalModelData::~FGNasalModelData()
796 SG_LOG(SG_NASAL, SG_ALERT, "Trying to run an <unload> script "
797 "without Nasal subsystem present.");
802 const char *s = _unload->getStringValue();
803 nasalSys->createModule(_module.c_str(), _module.c_str(), s, strlen(s), _props);
805 nasalSys->deleteModule(_module.c_str());