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 // Read and return file contents in a single buffer. Note use of
26 // stat() to get the file size. This is a win32 function, believe it
27 // or not. :) Note the REALLY IMPORTANT use of the "b" flag to fopen.
28 // Text mode brain damage will kill us if we're trying to do bytewise
30 static char* readfile(const char* file, int* lenOut)
33 if(stat(file, &data) != 0) return 0;
34 FILE* f = fopen(file, "rb");
36 char* buf = new char[data.st_size];
37 *lenOut = fread(buf, 1, data.st_size, f);
39 if(*lenOut != data.st_size) {
40 // Shouldn't happen, but warn anyway since it represents a
41 // platform bug and not a typical runtime error (missing file,
43 SG_LOG(SG_NASAL, SG_ALERT,
44 "ERROR in Nasal initialization: " <<
45 "short count returned from fread() of " << file <<
46 ". Check your C library!");
53 FGNasalSys::FGNasalSys()
58 _nextGCKey = 0; // Any value will do
60 _purgeListeners = false;
63 // Does a naCall() in a new context. Wrapped here to make lock
64 // tracking easier. Extension functions are called with the lock, but
65 // we have to release it before making a new naCall(). So rather than
66 // drop the lock in every extension function that might call back into
67 // Nasal, we keep a stack depth counter here and only unlock/lock
68 // around the naCall if it isn't the first one.
69 naRef FGNasalSys::call(naRef code, naRef locals)
71 naContext ctx = naNewContext();
72 if(_callCount) naModUnlock();
74 naRef result = naCall(ctx, code, 0, 0, naNil(), locals);
78 if(_callCount) naModLock();
83 FGNasalSys::~FGNasalSys()
85 map<int, FGNasalListener *>::iterator it, end = _listener.end();
86 for(it = _listener.begin(); it != end; ++it)
89 // Nasal doesn't have a "destroy context" API yet. :(
90 // Not a problem for a global subsystem that will never be
91 // destroyed. And the context is actually a global, so no memory
92 // is technically leaked (although the GC pool memory obviously
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 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
263 nasal->setTimer(argc, args);
267 // setlistener(func, property, bool) extension function. Falls through to
268 // FGNasalSys::setListener(). See there for docs.
269 static naRef f_setlistener(naContext c, naRef me, int argc, naRef* args)
271 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
272 return nasal->setListener(argc, args);
275 // removelistener(int) extension function. Falls through to
276 // FGNasalSys::removeListener(). See there for docs.
277 static naRef f_removelistener(naContext c, naRef me, int argc, naRef* args)
279 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
280 return nasal->removeListener(c, argc, args);
283 // Returns a ghost handle to the argument to the currently executing
285 static naRef f_cmdarg(naContext c, naRef me, int argc, naRef* args)
287 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
288 return nasal->cmdArgGhost();
291 // Sets up a property interpolation. The first argument is either a
292 // ghost (SGPropertyNode_ptr*) or a string (global property path) to
293 // interpolate. The second argument is a vector of pairs of
294 // value/delta numbers.
295 static naRef f_interpolate(naContext c, naRef me, int argc, naRef* args)
297 SGPropertyNode* node;
298 naRef prop = argc > 0 ? args[0] : naNil();
299 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
300 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
303 naRef curve = argc > 1 ? args[1] : naNil();
304 if(!naIsVector(curve)) return naNil();
305 int nPoints = naVec_size(curve) / 2;
306 double* values = new double[nPoints];
307 double* deltas = new double[nPoints];
308 for(int i=0; i<nPoints; i++) {
309 values[i] = naNumValue(naVec_get(curve, 2*i)).num;
310 deltas[i] = naNumValue(naVec_get(curve, 2*i+1)).num;
313 ((SGInterpolator*)globals->get_subsystem("interpolator"))
314 ->interpolate(node, nPoints, values, deltas);
319 // This is a better RNG than the one in the default Nasal distribution
320 // (which is based on the C library rand() implementation). It will
322 static naRef f_rand(naContext c, naRef me, int argc, naRef* args)
324 return naNum(sg_random());
327 static naRef f_srand(naContext c, naRef me, int argc, naRef* args)
333 // Return an array listing of all files in a directory
334 static naRef f_directory(naContext c, naRef me, int argc, naRef* args)
336 if(argc != 1 || !naIsString(args[0]))
337 naRuntimeError(c, "bad arguments to directory()");
338 naRef ldir = args[0];
339 ulDir* dir = ulOpenDir(naStr_data(args[0]));
340 if(!dir) return naNil();
341 naRef result = naNewVector(c);
343 while((dent = ulReadDir(dir)))
344 naVec_append(result, naStr_fromdata(naNewString(c), dent->d_name,
345 strlen(dent->d_name)));
350 // Table of extension functions. Terminate with zeros.
351 static struct { char* name; naCFunction func; } funcs[] = {
352 { "getprop", f_getprop },
353 { "setprop", f_setprop },
354 { "print", f_print },
355 { "_fgcommand", f_fgcommand },
356 { "settimer", f_settimer },
357 { "_setlistener", f_setlistener },
358 { "removelistener", f_removelistener },
359 { "_cmdarg", f_cmdarg },
360 { "_interpolate", f_interpolate },
362 { "srand", f_srand },
363 { "directory", f_directory },
367 naRef FGNasalSys::cmdArgGhost()
369 return propNodeGhost(_cmdArg);
372 void FGNasalSys::init()
376 _context = naNewContext();
378 // Start with globals. Add it to itself as a recursive
379 // sub-reference under the name "globals". This gives client-code
380 // write access to the namespace if someone wants to do something
382 _globals = naStdLib(_context);
383 naSave(_context, _globals);
384 hashset(_globals, "globals", _globals);
386 // Add in the math library under "math"
387 hashset(_globals, "math", naMathLib(_context));
389 // Add in the IO library. Disabled currently until after the
391 // hashset(_globals, "io", naIOLib(_context));
392 // hashset(_globals, "bits", naBitsLib(_context));
394 // Add our custom extension functions:
395 for(i=0; funcs[i].name; i++)
396 hashset(_globals, funcs[i].name,
397 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
399 // And our SGPropertyNode wrapper
400 hashset(_globals, "props", genPropsModule());
402 // Make a "__gcsave" hash to hold the naRef objects which get
403 // passed to handles outside the interpreter (to protect them from
404 // begin garbage-collected).
405 _gcHash = naNewHash(_context);
406 hashset(_globals, "__gcsave", _gcHash);
408 // Now load the various source files in the Nasal directory
409 SGPath p(globals->get_fg_root());
412 ulDir* dir = ulOpenDir(p.c_str());
413 while(dir && (dent = ulReadDir(dir)) != 0) {
415 fullpath.append(dent->d_name);
416 SGPath file(dent->d_name);
417 if(file.extension() != "nas") continue;
418 loadModule(fullpath, file.base().c_str());
422 // set signal and remove node to avoid restoring at reinit
423 const char *s = "nasal-dir-initialized";
424 SGPropertyNode *signal = fgGetNode("/sim/signals", true);
425 signal->setBoolValue(s, true);
426 signal->removeChildren(s);
428 // Pull scripts out of the property tree, too
429 loadPropertyScripts();
432 void FGNasalSys::update(double)
434 if(_purgeListeners) {
435 _purgeListeners = false;
436 map<int, FGNasalListener *>::iterator it;
437 for(it = _listener.end(); it != _listener.end();) {
438 FGNasalListener *nl = it->second;
440 _listener.erase(it--);
449 // Loads the scripts found under /nasal in the global tree
450 void FGNasalSys::loadPropertyScripts()
452 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
455 for(int i=0; i<nasal->nChildren(); i++) {
456 SGPropertyNode* n = nasal->getChild(i);
458 const char* module = n->getName();
459 if(n->hasChild("module"))
460 module = n->getStringValue("module");
462 // allow multiple files to be specified within in a single
466 bool file_specified = false;
467 while ( (fn = n->getChild("file", j)) != NULL ) {
468 file_specified = true;
469 const char* file = fn->getStringValue();
470 SGPath p(globals->get_fg_root());
472 loadModule(p, module);
476 // Old code which only allowed a single file to be specified per module
478 const char* file = n->getStringValue("file");
479 if(!n->hasChild("file")) file = 0; // Hrm...
481 SGPath p(globals->get_fg_root());
483 loadModule(p, module);
487 const char* src = n->getStringValue("script");
488 if(!n->hasChild("script")) src = 0; // Hrm...
490 createModule(module, n->getPath(), src, strlen(src));
492 if(!file_specified && !src)
493 SG_LOG(SG_NASAL, SG_ALERT, "Nasal error: " <<
494 "no <file> or <script> defined in " <<
495 "/nasal/" << module);
499 // Logs a runtime error, with stack trace, to the FlightGear log stream
500 void FGNasalSys::logError(naContext context)
502 SG_LOG(SG_NASAL, SG_ALERT,
503 "Nasal runtime error: " << naGetError(context));
504 SG_LOG(SG_NASAL, SG_ALERT,
505 " at " << naStr_data(naGetSourceFile(context, 0)) <<
506 ", line " << naGetLine(context, 0));
507 for(int i=1; i<naStackDepth(context); i++)
508 SG_LOG(SG_NASAL, SG_ALERT,
509 " called from: " << naStr_data(naGetSourceFile(context, i)) <<
510 ", line " << naGetLine(context, i));
513 // Reads a script file, executes it, and places the resulting
514 // namespace into the global namespace under the specified module
516 void FGNasalSys::loadModule(SGPath file, const char* module)
519 char* buf = readfile(file.c_str(), &len);
521 SG_LOG(SG_NASAL, SG_ALERT,
522 "Nasal error: could not read script file " << file.c_str()
523 << " into module " << module);
527 createModule(module, file.c_str(), buf, len);
531 // Parse and run. Save the local variables namespace, as it will
532 // become a sub-object of globals. The optional "arg" argument can be
533 // used to pass an associated property node to the module, which can then
534 // be accessed via cmdarg(). (This is, for example, used by XML dialogs.)
535 void FGNasalSys::createModule(const char* moduleName, const char* fileName,
536 const char* src, int len, const SGPropertyNode* arg)
538 naRef code = parse(fileName, src, len);
542 // See if we already have a module hash to use. This allows the
543 // user to, for example, add functions to the built-in math
544 // module. Make a new one if necessary.
546 naRef modname = naNewString(_context);
547 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
548 if(!naHash_get(_globals, modname, &locals))
549 locals = naNewHash(_context);
551 _cmdArg = (SGPropertyNode*)arg;
554 hashset(_globals, moduleName, locals);
557 void FGNasalSys::deleteModule(const char* moduleName)
559 naRef modname = naNewString(_context);
560 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
561 naHash_delete(_globals, modname);
564 naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
567 naRef srcfile = naNewString(_context);
568 naStr_fromdata(srcfile, (char*)filename, strlen(filename));
569 naRef code = naParseCode(_context, srcfile, 1, (char*)buf, len, &errLine);
571 SG_LOG(SG_NASAL, SG_ALERT,
572 "Nasal parse error: " << naGetError(_context) <<
573 " in "<< filename <<", line " << errLine);
577 // Bind to the global namespace before returning
578 return naBindFunction(_context, code, _globals);
581 bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
583 const char* nasal = arg->getStringValue("script");
584 const char* moduleName = arg->getStringValue("module");
585 naRef code = parse(arg->getPath(true), nasal, strlen(nasal));
586 if(naIsNil(code)) return false;
588 naContext c = naNewContext();
589 naRef locals = naNil();
591 naRef modname = naNewString(c);
592 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
593 if(!naHash_get(_globals, modname, &locals))
594 locals = naNewHash(c);
596 // Cache the command 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;
606 // settimer(func, dt, simtime) extension function. The first argument
607 // is a Nasal function to call, the second is a delta time (from now),
608 // in seconds. The third, if present, is a boolean value indicating
609 // that "real world" time (rather than simulator time) is to be used.
611 // Implementation note: the FGTimer objects don't live inside the
612 // garbage collector, so the Nasal handler functions have to be
613 // "saved" somehow lest they be inadvertently cleaned. In this case,
614 // they are inserted into a globals.__gcsave hash and removed on
616 void FGNasalSys::setTimer(int argc, naRef* args)
618 // Extract the handler, delta, and simtime arguments:
619 naRef handler = argc > 0 ? args[0] : naNil();
620 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
623 naRef delta = argc > 1 ? args[1] : naNil();
624 if(naIsNil(delta)) return;
626 bool simtime = (argc > 2 && naTrue(args[2])) ? false : true;
628 // Generate and register a C++ timer handler
629 NasalTimer* t = new NasalTimer;
630 t->handler = handler;
631 t->gcKey = gcSave(handler);
634 globals->get_event_mgr()->addEvent("NasalTimer",
635 t, &NasalTimer::timerExpired,
639 void FGNasalSys::handleTimer(NasalTimer* t)
641 call(t->handler, naNil());
645 int FGNasalSys::gcSave(naRef r)
647 int key = _nextGCKey++;
648 naHash_set(_gcHash, naNum(key), r);
652 void FGNasalSys::gcRelease(int key)
654 naHash_delete(_gcHash, naNum(key));
657 void FGNasalSys::NasalTimer::timerExpired()
659 nasal->handleTimer(this);
663 int FGNasalSys::_listenerId = 0;
665 // setlistener(property, func, bool) extension function. The first argument
666 // is either a ghost (SGPropertyNode_ptr*) or a string (global property
667 // path), the second is a Nasal function, the optional third one a bool.
668 // If the bool is true, then the listener is executed initially. The
669 // setlistener() function returns a unique id number, that can be used
670 // as argument to the removelistener() function.
671 naRef FGNasalSys::setListener(int argc, naRef* args)
673 SGPropertyNode_ptr node;
674 naRef prop = argc > 0 ? args[0] : naNil();
675 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
676 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
680 SG_LOG(SG_NASAL, SG_DEBUG, "Attaching listener to tied property " <<
683 naRef handler = argc > 1 ? args[1] : naNil();
684 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
687 bool initial = argc > 2 && naTrue(args[2]);
689 FGNasalListener *nl = new FGNasalListener(node, handler, this,
691 node->addChangeListener(nl, initial);
693 _listener[_listenerId] = nl;
694 return naNum(_listenerId++);
697 // removelistener(int) extension function. The argument is the id of
698 // a listener as returned by the setlistener() function.
699 naRef FGNasalSys::removeListener(naContext c, int argc, naRef* args)
701 naRef id = argc > 0 ? args[0] : naNil();
702 map<int, FGNasalListener *>::iterator it = _listener.find(int(id.num));
704 if(!naIsNum(id) || it == _listener.end() || it->second->_dead) {
705 naRuntimeError(c, "removelistener() with invalid listener id");
709 FGNasalListener *nl = it->second;
712 _purgeListeners = true;
718 return naNum(_listener.size());
723 // FGNasalListener class.
725 FGNasalListener::FGNasalListener(SGPropertyNode_ptr node, naRef handler,
726 FGNasalSys* nasal, int key) :
736 FGNasalListener::~FGNasalListener()
738 _node->removeChangeListener(this);
739 _nas->gcRelease(_gcKey);
742 void FGNasalListener::valueChanged(SGPropertyNode* node)
744 // drop recursive listener calls
749 _nas->_cmdArg = node;
750 _nas->call(_handler, naNil());
757 // FGNasalModelData class. If sgLoad3DModel() is called with a pointer to
758 // such a class, then it lets modelLoaded() run the <load> script, and the
759 // destructor the <unload> script. The latter happens when the model branch
760 // is removed from the scene graph.
762 void FGNasalModelData::modelLoaded(const string& path, SGPropertyNode *prop,
765 SGPropertyNode *n = prop->getNode("nasal"), *load;
769 load = n->getNode("load");
770 _unload = n->getNode("unload");
771 if(!load && !_unload)
775 const char *s = load ? load->getStringValue() : "";
776 FGNasalSys *nas = (FGNasalSys *)globals->get_subsystem("nasal");
777 nas->createModule(_module.c_str(), _module.c_str(), s, strlen(s));
780 FGNasalModelData::~FGNasalModelData()
785 FGNasalSys *nas = (FGNasalSys *)globals->get_subsystem("nasal");
787 SG_LOG(SG_NASAL, SG_ALERT, "Trying to run an <unload> script "
788 "without Nasal subsystem present.");
793 const char *s = _unload->getStringValue();
794 nas->createModule(_module.c_str(), _module.c_str(), s, strlen(s));
796 nas->deleteModule(_module.c_str());