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
61 FGNasalSys::~FGNasalSys()
63 // Nasal doesn't have a "destroy context" API yet. :(
64 // Not a problem for a global subsystem that will never be
65 // destroyed. And the context is actually a global, so no memory
66 // is technically leaked (although the GC pool memory obviously
72 bool FGNasalSys::parseAndRun(const char* sourceCode)
74 naRef code = parse("FGNasalSys::parseAndRun()", sourceCode,
79 naCall(_context, code, 0, 0, naNil(), naNil());
81 if(!naGetError(_context)) return true;
86 FGNasalScript* FGNasalSys::parseScript(const char* src, const char* name)
88 FGNasalScript* script = new FGNasalScript();
89 script->_gcKey = -1; // important, if we delete it on a parse
90 script->_nas = this; // error, don't clobber a real handle!
94 sprintf(buf, "FGNasalScript@%p", script);
98 script->_code = parse(name, src, strlen(src));
99 if(naIsNil(script->_code)) {
104 script->_gcKey = gcSave(script->_code);
108 // Utility. Sets a named key in a hash by C string, rather than nasal
110 void FGNasalSys::hashset(naRef hash, const char* key, naRef val)
112 naRef s = naNewString(_context);
113 naStr_fromdata(s, (char*)key, strlen(key));
114 naHash_set(hash, s, val);
117 // The get/setprop functions accept a *list* of strings and walk
118 // through the property tree with them to find the appropriate node.
119 // This allows a Nasal object to hold onto a property path and use it
120 // like a node object, e.g. setprop(ObjRoot, "size-parsecs", 2.02). This
121 // is the utility function that walks the property tree.
122 // Future enhancement: support integer arguments to specify array
124 static SGPropertyNode* findnode(naContext c, naRef* vec, int len)
126 SGPropertyNode* p = globals->get_props();
127 for(int i=0; i<len; i++) {
129 if(!naIsString(a)) return 0;
130 p = p->getNode(naStr_data(a));
136 // getprop() extension function. Concatenates its string arguments as
137 // property names and returns the value of the specified property. Or
138 // nil if it doesn't exist.
139 static naRef f_getprop(naContext c, naRef me, int argc, naRef* args)
141 const SGPropertyNode* p = findnode(c, args, argc);
142 if(!p) return naNil();
144 switch(p->getType()) {
145 case SGPropertyNode::BOOL: case SGPropertyNode::INT:
146 case SGPropertyNode::LONG: case SGPropertyNode::FLOAT:
147 case SGPropertyNode::DOUBLE:
148 return naNum(p->getDoubleValue());
150 case SGPropertyNode::STRING:
151 case SGPropertyNode::UNSPECIFIED:
153 naRef nastr = naNewString(c);
154 const char* val = p->getStringValue();
155 naStr_fromdata(nastr, (char*)val, strlen(val));
158 case SGPropertyNode::ALIAS: // <--- FIXME, recurse?
164 // setprop() extension function. Concatenates its string arguments as
165 // property names and sets the value of the specified property to the
167 static naRef f_setprop(naContext c, naRef me, int argc, naRef* args)
170 char buf[BUFLEN + 1];
174 for(int i=0; i<argc-1; i++) {
175 naRef s = naStringValue(c, args[i]);
176 if(naIsNil(s)) return naNil();
177 strncpy(p, naStr_data(s), buflen);
179 buflen = BUFLEN - (p - buf);
180 if(i < (argc-2) && buflen > 0) {
186 SGPropertyNode* props = globals->get_props();
187 naRef val = args[argc-1];
188 if(naIsString(val)) props->setStringValue(buf, naStr_data(val));
189 else props->setDoubleValue(buf, naNumValue(val).num);
194 // print() extension function. Concatenates and prints its arguments
195 // to the FlightGear log. Uses the highest log level (SG_ALERT), to
196 // make sure it appears. Is there better way to do this?
197 static naRef f_print(naContext c, naRef me, int argc, naRef* args)
200 char buf[BUFLEN + 1];
201 buf[BUFLEN] = 0; // extra nul to handle strncpy brain damage
202 buf[0] = 0; // Zero-length in case there are no arguments
206 for(int i=0; i<n; i++) {
207 naRef s = naStringValue(c, args[i]);
208 if(naIsNil(s)) continue;
209 strncpy(p, naStr_data(s), buflen);
211 buflen = BUFLEN - (p - buf);
212 if(buflen <= 0) break;
214 SG_LOG(SG_GENERAL, SG_ALERT, buf);
219 // fgcommand() extension function. Executes a named command via the
220 // FlightGear command manager. Takes a single property node name as
222 static naRef f_fgcommand(naContext c, naRef me, int argc, naRef* args)
224 if(argc < 2 || !naIsString(args[0]) || !naIsGhost(args[1]))
225 naRuntimeError(c, "bad arguments to fgcommand()");
226 naRef cmd = args[0], props = args[1];
227 SGPropertyNode_ptr* node = (SGPropertyNode_ptr*)naGhost_ptr(props);
228 globals->get_commands()->execute(naStr_data(cmd), *node);
233 // settimer(func, dt, simtime) extension function. Falls through to
234 // FGNasalSys::setTimer(). See there for docs.
235 static naRef f_settimer(naContext c, naRef me, int argc, naRef* args)
237 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
238 nasal->setTimer(argc, args);
242 // setlistener(func, property, bool) extension function. Falls through to
243 // FGNasalSys::setListener(). See there for docs.
244 static naRef f_setlistener(naContext c, naRef me, int argc, naRef* args)
246 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
247 return nasal->setListener(argc, args);
250 // removelistener(int) extension function. Falls through to
251 // FGNasalSys::removeListener(). See there for docs.
252 static naRef f_removelistener(naContext c, naRef me, int argc, naRef* args)
254 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
255 return nasal->removeListener(argc, args);
258 // Returns a ghost handle to the argument to the currently executing
260 static naRef f_cmdarg(naContext c, naRef me, int argc, naRef* args)
262 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
263 return nasal->cmdArgGhost();
266 // Sets up a property interpolation. The first argument is either a
267 // ghost (SGPropertyNode_ptr*) or a string (global property path) to
268 // interpolate. The second argument is a vector of pairs of
269 // value/delta numbers.
270 static naRef f_interpolate(naContext c, naRef me, int argc, naRef* args)
272 SGPropertyNode* node;
273 naRef prop = argc > 0 ? args[0] : naNil();
274 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
275 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
278 naRef curve = argc > 1 ? args[1] : naNil();
279 if(!naIsVector(curve)) return naNil();
280 int nPoints = naVec_size(curve) / 2;
281 double* values = new double[nPoints];
282 double* deltas = new double[nPoints];
283 for(int i=0; i<nPoints; i++) {
284 values[i] = naNumValue(naVec_get(curve, 2*i)).num;
285 deltas[i] = naNumValue(naVec_get(curve, 2*i+1)).num;
288 ((SGInterpolator*)globals->get_subsystem("interpolator"))
289 ->interpolate(node, nPoints, values, deltas);
294 // This is a better RNG than the one in the default Nasal distribution
295 // (which is based on the C library rand() implementation). It will
297 static naRef f_rand(naContext c, naRef me, int argc, naRef* args)
299 return naNum(sg_random());
302 static naRef f_srand(naContext c, naRef me, int argc, naRef* args)
308 // Return an array listing of all files in a directory
309 static naRef f_directory(naContext c, naRef me, int argc, naRef* args)
311 if(argc != 1 || !naIsString(args[0]))
312 naRuntimeError(c, "bad arguments to directory()");
313 naRef ldir = args[0];
314 ulDir* dir = ulOpenDir(naStr_data(args[0]));
315 if(!dir) return naNil();
316 naRef result = naNewVector(c);
318 while((dent = ulReadDir(dir)))
319 naVec_append(result, naStr_fromdata(naNewString(c), dent->d_name,
320 strlen(dent->d_name)));
325 // Table of extension functions. Terminate with zeros.
326 static struct { char* name; naCFunction func; } funcs[] = {
327 { "getprop", f_getprop },
328 { "setprop", f_setprop },
329 { "print", f_print },
330 { "_fgcommand", f_fgcommand },
331 { "settimer", f_settimer },
332 { "_setlistener", f_setlistener },
333 { "removelistener", f_removelistener },
334 { "_cmdarg", f_cmdarg },
335 { "_interpolate", f_interpolate },
337 { "srand", f_srand },
338 { "directory", f_directory },
342 naRef FGNasalSys::cmdArgGhost()
344 return propNodeGhost(_cmdArg);
347 void FGNasalSys::init()
351 _context = naNewContext();
353 // Start with globals. Add it to itself as a recursive
354 // sub-reference under the name "globals". This gives client-code
355 // write access to the namespace if someone wants to do something
357 _globals = naStdLib(_context);
358 naSave(_context, _globals);
359 hashset(_globals, "globals", _globals);
361 // Add in the math library under "math"
362 hashset(_globals, "math", naMathLib(_context));
364 // Add our custom extension functions:
365 for(i=0; funcs[i].name; i++)
366 hashset(_globals, funcs[i].name,
367 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
369 // And our SGPropertyNode wrapper
370 hashset(_globals, "props", genPropsModule());
372 // Make a "__gcsave" hash to hold the naRef objects which get
373 // passed to handles outside the interpreter (to protect them from
374 // begin garbage-collected).
375 _gcHash = naNewHash(_context);
376 hashset(_globals, "__gcsave", _gcHash);
378 // Now load the various source files in the Nasal directory
379 SGPath p(globals->get_fg_root());
382 ulDir* dir = ulOpenDir(p.c_str());
383 while(dir && (dent = ulReadDir(dir)) != 0) {
385 fullpath.append(dent->d_name);
386 SGPath file(dent->d_name);
387 if(file.extension() != "nas") continue;
388 loadModule(fullpath, file.base().c_str());
392 // Pull scripts out of the property tree, too
393 loadPropertyScripts();
396 // Loads the scripts found under /nasal in the global tree
397 void FGNasalSys::loadPropertyScripts()
399 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
402 for(int i=0; i<nasal->nChildren(); i++) {
403 SGPropertyNode* n = nasal->getChild(i);
405 const char* module = n->getName();
406 if(n->hasChild("module"))
407 module = n->getStringValue("module");
409 // allow multiple files to be specified within in a single
413 bool file_specified = false;
414 while ( (fn = n->getChild("file", j)) != NULL ) {
415 file_specified = true;
416 const char* file = fn->getStringValue();
417 SGPath p(globals->get_fg_root());
419 loadModule(p, module);
423 // Old code which only allowed a single file to be specified per module
425 const char* file = n->getStringValue("file");
426 if(!n->hasChild("file")) file = 0; // Hrm...
428 SGPath p(globals->get_fg_root());
430 loadModule(p, module);
434 const char* src = n->getStringValue("script");
435 if(!n->hasChild("script")) src = 0; // Hrm...
437 createModule(module, n->getPath(), src, strlen(src));
439 if(!file_specified && !src)
440 SG_LOG(SG_NASAL, SG_ALERT, "Nasal error: " <<
441 "no <file> or <script> defined in " <<
442 "/nasal/" << module);
446 // Logs a runtime error, with stack trace, to the FlightGear log stream
447 void FGNasalSys::logError(naContext context)
449 SG_LOG(SG_NASAL, SG_ALERT,
450 "Nasal runtime error: " << naGetError(context));
451 SG_LOG(SG_NASAL, SG_ALERT,
452 " at " << naStr_data(naGetSourceFile(context, 0)) <<
453 ", line " << naGetLine(context, 0));
454 for(int i=1; i<naStackDepth(context); i++)
455 SG_LOG(SG_NASAL, SG_ALERT,
456 " called from: " << naStr_data(naGetSourceFile(context, i)) <<
457 ", line " << naGetLine(context, i));
460 // Reads a script file, executes it, and places the resulting
461 // namespace into the global namespace under the specified module
463 void FGNasalSys::loadModule(SGPath file, const char* module)
466 char* buf = readfile(file.c_str(), &len);
468 SG_LOG(SG_NASAL, SG_ALERT,
469 "Nasal error: could not read script file " << file.c_str()
470 << " into module " << module);
474 createModule(module, file.c_str(), buf, len);
478 // Parse and run. Save the local variables namespace, as it will
479 // become a sub-object of globals.
480 void FGNasalSys::createModule(const char* moduleName, const char* fileName,
481 const char* src, int len)
483 naRef code = parse(fileName, src, len);
487 // See if we already have a module hash to use. This allows the
488 // user to, for example, add functions to the built-in math
489 // module. Make a new one if necessary.
491 naRef modname = naNewString(_context);
492 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
493 if(!naHash_get(_globals, modname, &locals))
494 locals = naNewHash(_context);
496 naCall(_context, code, 0, 0, naNil(), locals);
497 if(naGetError(_context)) {
501 hashset(_globals, moduleName, locals);
504 void FGNasalSys::deleteModule(const char* moduleName)
506 naRef modname = naNewString(_context);
507 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
509 naHash_delete(_globals, modname);
513 naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
516 naRef srcfile = naNewString(_context);
517 naStr_fromdata(srcfile, (char*)filename, strlen(filename));
518 naRef code = naParseCode(_context, srcfile, 1, (char*)buf, len, &errLine);
520 SG_LOG(SG_NASAL, SG_ALERT,
521 "Nasal parse error: " << naGetError(_context) <<
522 " in "<< filename <<", line " << errLine);
526 // Bind to the global namespace before returning
527 return naBindFunction(_context, code, _globals);
530 bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
532 const char* nasal = arg->getStringValue("script");
533 const char* moduleName = arg->getStringValue("module");
534 naRef code = parse(arg->getPath(true), nasal, strlen(nasal));
535 if(naIsNil(code)) return false;
537 naContext c = naNewContext();
538 naRef locals = naNil();
540 naRef modname = naNewString(c);
541 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
542 if(!naHash_get(_globals, modname, &locals))
543 locals = naNewHash(c);
545 // Cache the command argument for inspection via cmdarg(). For
546 // performance reasons, we won't bother with it if the invoked
547 // code doesn't need it.
548 _cmdArg = (SGPropertyNode*)arg;
552 naRef result = naCall(c, code, 0, 0, naNil(), locals);
554 bool error = naGetError(c);
562 // settimer(func, dt, simtime) extension function. The first argument
563 // is a Nasal function to call, the second is a delta time (from now),
564 // in seconds. The third, if present, is a boolean value indicating
565 // that "real world" time (rather than simulator time) is to be used.
567 // Implementation note: the FGTimer objects don't live inside the
568 // garbage collector, so the Nasal handler functions have to be
569 // "saved" somehow lest they be inadvertently cleaned. In this case,
570 // they are inserted into a globals.__gcsave hash and removed on
572 void FGNasalSys::setTimer(int argc, naRef* args)
574 // Extract the handler, delta, and simtime arguments:
575 naRef handler = argc > 0 ? args[0] : naNil();
576 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
579 naRef delta = argc > 1 ? args[1] : naNil();
580 if(naIsNil(delta)) return;
582 bool simtime = (argc > 2 && naTrue(args[2])) ? false : true;
584 // Generate and register a C++ timer handler
585 NasalTimer* t = new NasalTimer;
586 t->handler = handler;
587 t->gcKey = gcSave(handler);
590 globals->get_event_mgr()->addEvent("NasalTimer",
591 t, &NasalTimer::timerExpired,
595 void FGNasalSys::handleTimer(NasalTimer* t)
597 naCall(_context, t->handler, 0, 0, naNil(), naNil());
598 if(naGetError(_context))
603 int FGNasalSys::gcSave(naRef r)
605 int key = _nextGCKey++;
606 naHash_set(_gcHash, naNum(key), r);
610 void FGNasalSys::gcRelease(int key)
612 naHash_delete(_gcHash, naNum(key));
615 void FGNasalSys::NasalTimer::timerExpired()
617 nasal->handleTimer(this);
621 int FGNasalSys::_listenerId = 0;
623 // setlistener(property, func, bool) extension function. The first argument
624 // is either a ghost (SGPropertyNode_ptr*) or a string (global property
625 // path), the second is a Nasal function, the optional third one a bool.
626 // If the bool is true, then the listener is executed initially. The
627 // setlistener() function returns a unique id number, that can be used
628 // as argument to the removelistener() function.
629 naRef FGNasalSys::setListener(int argc, naRef* args)
631 SGPropertyNode_ptr node;
632 naRef prop = argc > 0 ? args[0] : naNil();
633 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
634 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
637 naRef handler = argc > 1 ? args[1] : naNil();
638 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
641 bool initial = argc > 2 && naTrue(args[2]);
643 FGNasalListener *nl = new FGNasalListener(node, handler, this,
645 node->addChangeListener(nl, initial);
647 _listener[_listenerId] = nl;
648 return naNum(_listenerId++);
651 // removelistener(int) extension function. The argument is the id of
652 // a listener as returned by the setlistener() function.
653 naRef FGNasalSys::removeListener(int argc, naRef* args)
655 naRef id = argc > 0 ? args[0] : naNil();
660 if (_listener.find(i) == _listener.end())
663 FGNasalListener *nl = _listener[i];
664 nl->_node->removeChangeListener(nl);
667 return naNum(_listener.size());
672 // FGNasalModelData class. If sgLoad3DModel() is called with a pointer to
673 // such a class, then it lets modelLoaded() run the <load> script, and the
674 // destructor the <unload> script. The latter happens when the model branch
675 // is removed from the scene graph.
677 void FGNasalModelData::modelLoaded(const string& path, SGPropertyNode *prop,
680 SGPropertyNode *n = prop->getNode("nasal"), *load;
684 load = n->getNode("load");
685 _unload = n->getNode("unload");
686 if (!load && !_unload)
690 const char *s = load ? load->getStringValue() : "";
691 FGNasalSys *nas = (FGNasalSys *)globals->get_subsystem("nasal");
692 nas->createModule(_module.c_str(), _module.c_str(), s, strlen(s));
695 FGNasalModelData::~FGNasalModelData()
700 FGNasalSys *nas = (FGNasalSys *)globals->get_subsystem("nasal");
702 SG_LOG(SG_NASAL, SG_ALERT, "Trying to run an <unload> script "
703 "without Nasal subsystem present.");
708 const char *s = _unload->getStringValue();
709 nas->createModule(_module.c_str(), _module.c_str(), s, strlen(s));
711 nas->deleteModule(_module.c_str());