13 #include <simgear/nasal/nasal.h>
14 #include <simgear/props/props.hxx>
15 #include <simgear/props/condition.hxx>
16 #include <simgear/math/sg_random.h>
17 #include <simgear/misc/sg_path.hxx>
18 #include <simgear/misc/interpolator.hxx>
19 #include <simgear/structure/commands.hxx>
21 #include <Main/globals.hxx>
22 #include <Main/fg_props.hxx>
24 #include "NasalSys.hxx"
26 // Read and return file contents in a single buffer. Note use of
27 // stat() to get the file size. This is a win32 function, believe it
28 // or not. :) Note the REALLY IMPORTANT use of the "b" flag to fopen.
29 // Text mode brain damage will kill us if we're trying to do bytewise
31 static char* readfile(const char* file, int* lenOut)
34 if(stat(file, &data) != 0) return 0;
35 FILE* f = fopen(file, "rb");
37 char* buf = new char[data.st_size];
38 *lenOut = fread(buf, 1, data.st_size, f);
40 if(*lenOut != data.st_size) {
41 // Shouldn't happen, but warn anyway since it represents a
42 // platform bug and not a typical runtime error (missing file,
44 SG_LOG(SG_NASAL, SG_ALERT,
45 "ERROR in Nasal initialization: " <<
46 "short count returned from fread() of " << file <<
47 ". Check your C library!");
54 FGNasalSys::FGNasalSys()
59 _nextGCKey = 0; // Any value will do
61 _purgeListeners = false;
64 // Does a naCall() in a new context. Wrapped here to make lock
65 // tracking easier. Extension functions are called with the lock, but
66 // we have to release it before making a new naCall(). So rather than
67 // drop the lock in every extension function that might call back into
68 // Nasal, we keep a stack depth counter here and only unlock/lock
69 // around the naCall if it isn't the first one.
70 naRef FGNasalSys::call(naRef code, naRef locals)
72 naContext ctx = naNewContext();
73 if(_callCount) naModUnlock();
75 naRef result = naCall(ctx, code, 0, 0, naNil(), locals);
79 if(_callCount) naModLock();
84 FGNasalSys::~FGNasalSys()
86 map<int, FGNasalListener *>::iterator it, end = _listener.end();
87 for(it = _listener.begin(); it != end; ++it)
90 // Nasal doesn't have a "destroy context" API yet. :(
91 // Not a problem for a global subsystem that will never be
92 // destroyed. And the context is actually a global, so no memory
93 // is technically leaked (although the GC pool memory obviously
99 bool FGNasalSys::parseAndRun(const char* sourceCode)
101 naRef code = parse("FGNasalSys::parseAndRun()", sourceCode,
109 FGNasalScript* FGNasalSys::parseScript(const char* src, const char* name)
111 FGNasalScript* script = new FGNasalScript();
112 script->_gcKey = -1; // important, if we delete it on a parse
113 script->_nas = this; // error, don't clobber a real handle!
117 sprintf(buf, "FGNasalScript@%p", script);
121 script->_code = parse(name, src, strlen(src));
122 if(naIsNil(script->_code)) {
127 script->_gcKey = gcSave(script->_code);
131 // Utility. Sets a named key in a hash by C string, rather than nasal
133 void FGNasalSys::hashset(naRef hash, const char* key, naRef val)
135 naRef s = naNewString(_context);
136 naStr_fromdata(s, (char*)key, strlen(key));
137 naHash_set(hash, s, val);
140 // The get/setprop functions accept a *list* of strings and walk
141 // through the property tree with them to find the appropriate node.
142 // This allows a Nasal object to hold onto a property path and use it
143 // like a node object, e.g. setprop(ObjRoot, "size-parsecs", 2.02). This
144 // is the utility function that walks the property tree.
145 // Future enhancement: support integer arguments to specify array
147 static SGPropertyNode* findnode(naContext c, naRef* vec, int len)
149 SGPropertyNode* p = globals->get_props();
151 for(int i=0; i<len; i++) {
153 if(!naIsString(a)) return 0;
154 p = p->getNode(naStr_data(a));
157 } catch (const string& err) {
158 naRuntimeError(c, (char *)err.c_str());
164 // getprop() extension function. Concatenates its string arguments as
165 // property names and returns the value of the specified property. Or
166 // nil if it doesn't exist.
167 static naRef f_getprop(naContext c, naRef me, int argc, naRef* args)
169 const SGPropertyNode* p = findnode(c, args, argc);
170 if(!p) return naNil();
172 switch(p->getType()) {
173 case SGPropertyNode::BOOL: case SGPropertyNode::INT:
174 case SGPropertyNode::LONG: case SGPropertyNode::FLOAT:
175 case SGPropertyNode::DOUBLE:
176 return naNum(p->getDoubleValue());
178 case SGPropertyNode::STRING:
179 case SGPropertyNode::UNSPECIFIED:
181 naRef nastr = naNewString(c);
182 const char* val = p->getStringValue();
183 naStr_fromdata(nastr, (char*)val, strlen(val));
186 case SGPropertyNode::ALIAS: // <--- FIXME, recurse?
192 // setprop() extension function. Concatenates its string arguments as
193 // property names and sets the value of the specified property to the
195 static naRef f_setprop(naContext c, naRef me, int argc, naRef* args)
198 char buf[BUFLEN + 1];
202 for(int i=0; i<argc-1; i++) {
203 naRef s = naStringValue(c, args[i]);
204 if(naIsNil(s)) return naNil();
205 strncpy(p, naStr_data(s), buflen);
207 buflen = BUFLEN - (p - buf);
208 if(i < (argc-2) && buflen > 0) {
214 SGPropertyNode* props = globals->get_props();
215 naRef val = args[argc-1];
217 if(naIsString(val)) props->setStringValue(buf, naStr_data(val));
219 naRef n = naNumValue(val);
221 naRuntimeError(c, "setprop() value is not string or number");
222 props->setDoubleValue(buf, n.num);
224 } catch (const string& err) {
225 naRuntimeError(c, (char *)err.c_str());
231 // print() extension function. Concatenates and prints its arguments
232 // to the FlightGear log. Uses the highest log level (SG_ALERT), to
233 // make sure it appears. Is there better way to do this?
234 static naRef f_print(naContext c, naRef me, int argc, naRef* args)
238 for(int i=0; i<n; i++) {
239 naRef s = naStringValue(c, args[i]);
240 if(naIsNil(s)) continue;
241 buf += naStr_data(s);
243 SG_LOG(SG_GENERAL, SG_ALERT, buf);
244 return naNum(buf.length());
247 // fgcommand() extension function. Executes a named command via the
248 // FlightGear command manager. Takes a single property node name as
250 static naRef f_fgcommand(naContext c, naRef me, int argc, naRef* args)
252 if(argc < 2 || !naIsString(args[0]) || !naIsGhost(args[1]))
253 naRuntimeError(c, "bad arguments to fgcommand()");
254 naRef cmd = args[0], props = args[1];
255 SGPropertyNode_ptr* node = (SGPropertyNode_ptr*)naGhost_ptr(props);
256 return naNum(globals->get_commands()->execute(naStr_data(cmd), *node));
259 // settimer(func, dt, simtime) extension function. Falls through to
260 // FGNasalSys::setTimer(). See there for docs.
261 static naRef f_settimer(naContext c, naRef me, int argc, naRef* args)
263 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
264 nasal->setTimer(argc, args);
268 // setlistener(func, property, bool) extension function. Falls through to
269 // FGNasalSys::setListener(). See there for docs.
270 static naRef f_setlistener(naContext c, naRef me, int argc, naRef* args)
272 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
273 return nasal->setListener(c, argc, args);
276 // removelistener(int) extension function. Falls through to
277 // FGNasalSys::removeListener(). See there for docs.
278 static naRef f_removelistener(naContext c, naRef me, int argc, naRef* args)
280 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
281 return nasal->removeListener(c, argc, args);
284 // condition(property) extension function. Evaluates standard <condition>
285 // (see $FG_ROOT/Docs/README.condition) and returns state.
286 static naRef f_condition(naContext c, naRef me, int argc, naRef* args)
288 SGPropertyNode* node;
289 naRef prop = argc > 0 ? args[0] : naNil();
290 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
291 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
293 naRuntimeError(c, "condition() with invalid property");
296 SGCondition *cond = sgReadCondition(globals->get_props(), node);
297 bool result = cond->test();
299 return naNum(result == true ? 1 : 0);
302 // Returns a ghost handle to the argument to the currently executing
304 static naRef f_cmdarg(naContext c, naRef me, int argc, naRef* args)
306 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
307 return nasal->cmdArgGhost();
310 // Sets up a property interpolation. The first argument is either a
311 // ghost (SGPropertyNode_ptr*) or a string (global property path) to
312 // interpolate. The second argument is a vector of pairs of
313 // value/delta numbers.
314 static naRef f_interpolate(naContext c, naRef me, int argc, naRef* args)
316 SGPropertyNode* node;
317 naRef prop = argc > 0 ? args[0] : naNil();
318 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
319 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
322 naRef curve = argc > 1 ? args[1] : naNil();
323 if(!naIsVector(curve)) return naNil();
324 int nPoints = naVec_size(curve) / 2;
325 double* values = new double[nPoints];
326 double* deltas = new double[nPoints];
327 for(int i=0; i<nPoints; i++) {
328 values[i] = naNumValue(naVec_get(curve, 2*i)).num;
329 deltas[i] = naNumValue(naVec_get(curve, 2*i+1)).num;
332 ((SGInterpolator*)globals->get_subsystem("interpolator"))
333 ->interpolate(node, nPoints, values, deltas);
338 // This is a better RNG than the one in the default Nasal distribution
339 // (which is based on the C library rand() implementation). It will
341 static naRef f_rand(naContext c, naRef me, int argc, naRef* args)
343 return naNum(sg_random());
346 static naRef f_srand(naContext c, naRef me, int argc, naRef* args)
352 // Return an array listing of all files in a directory
353 static naRef f_directory(naContext c, naRef me, int argc, naRef* args)
355 if(argc != 1 || !naIsString(args[0]))
356 naRuntimeError(c, "bad arguments to directory()");
357 naRef ldir = args[0];
358 ulDir* dir = ulOpenDir(naStr_data(args[0]));
359 if(!dir) return naNil();
360 naRef result = naNewVector(c);
362 while((dent = ulReadDir(dir)))
363 naVec_append(result, naStr_fromdata(naNewString(c), dent->d_name,
364 strlen(dent->d_name)));
369 // Table of extension functions. Terminate with zeros.
370 static struct { char* name; naCFunction func; } funcs[] = {
371 { "getprop", f_getprop },
372 { "setprop", f_setprop },
373 { "print", f_print },
374 { "_fgcommand", f_fgcommand },
375 { "settimer", f_settimer },
376 { "_setlistener", f_setlistener },
377 { "removelistener", f_removelistener },
378 { "_condition", f_condition },
379 { "_cmdarg", f_cmdarg },
380 { "_interpolate", f_interpolate },
382 { "srand", f_srand },
383 { "directory", f_directory },
387 naRef FGNasalSys::cmdArgGhost()
389 return propNodeGhost(_cmdArg);
392 void FGNasalSys::init()
396 _context = naNewContext();
398 // Start with globals. Add it to itself as a recursive
399 // sub-reference under the name "globals". This gives client-code
400 // write access to the namespace if someone wants to do something
402 _globals = naStdLib(_context);
403 naSave(_context, _globals);
404 hashset(_globals, "globals", _globals);
406 // Add in the math library under "math"
407 hashset(_globals, "math", naMathLib(_context));
409 // Add in the IO library. Disabled currently until after the
411 // hashset(_globals, "io", naIOLib(_context));
412 // hashset(_globals, "bits", naBitsLib(_context));
414 // Add our custom extension functions:
415 for(i=0; funcs[i].name; i++)
416 hashset(_globals, funcs[i].name,
417 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
419 // And our SGPropertyNode wrapper
420 hashset(_globals, "props", genPropsModule());
422 // Make a "__gcsave" hash to hold the naRef objects which get
423 // passed to handles outside the interpreter (to protect them from
424 // begin garbage-collected).
425 _gcHash = naNewHash(_context);
426 hashset(_globals, "__gcsave", _gcHash);
428 // Now load the various source files in the Nasal directory
429 SGPath p(globals->get_fg_root());
432 ulDir* dir = ulOpenDir(p.c_str());
433 while(dir && (dent = ulReadDir(dir)) != 0) {
435 fullpath.append(dent->d_name);
436 SGPath file(dent->d_name);
437 if(file.extension() != "nas") continue;
438 loadModule(fullpath, file.base().c_str());
442 // set signal and remove node to avoid restoring at reinit
443 const char *s = "nasal-dir-initialized";
444 SGPropertyNode *signal = fgGetNode("/sim/signals", true);
445 signal->setBoolValue(s, true);
446 signal->removeChildren(s);
448 // Pull scripts out of the property tree, too
449 loadPropertyScripts();
452 void FGNasalSys::update(double)
454 if(_purgeListeners) {
455 _purgeListeners = false;
456 map<int, FGNasalListener *>::iterator it;
457 for(it = _listener.begin(); it != _listener.end();) {
458 FGNasalListener *nl = it->second;
460 _listener.erase(it++);
469 // Loads the scripts found under /nasal in the global tree
470 void FGNasalSys::loadPropertyScripts()
472 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
475 for(int i=0; i<nasal->nChildren(); i++) {
476 SGPropertyNode* n = nasal->getChild(i);
478 const char* module = n->getName();
479 if(n->hasChild("module"))
480 module = n->getStringValue("module");
482 // allow multiple files to be specified within in a single
486 bool file_specified = false;
487 while ( (fn = n->getChild("file", j)) != NULL ) {
488 file_specified = true;
489 const char* file = fn->getStringValue();
490 SGPath p(globals->get_fg_root());
492 loadModule(p, module);
496 // Old code which only allowed a single file to be specified per module
498 const char* file = n->getStringValue("file");
499 if(!n->hasChild("file")) file = 0; // Hrm...
501 SGPath p(globals->get_fg_root());
503 loadModule(p, module);
507 const char* src = n->getStringValue("script");
508 if(!n->hasChild("script")) src = 0; // Hrm...
510 createModule(module, n->getPath(), src, strlen(src));
512 if(!file_specified && !src)
513 SG_LOG(SG_NASAL, SG_ALERT, "Nasal error: " <<
514 "no <file> or <script> defined in " <<
515 "/nasal/" << module);
519 // Logs a runtime error, with stack trace, to the FlightGear log stream
520 void FGNasalSys::logError(naContext context)
522 SG_LOG(SG_NASAL, SG_ALERT,
523 "Nasal runtime error: " << naGetError(context));
524 SG_LOG(SG_NASAL, SG_ALERT,
525 " at " << naStr_data(naGetSourceFile(context, 0)) <<
526 ", line " << naGetLine(context, 0));
527 for(int i=1; i<naStackDepth(context); i++)
528 SG_LOG(SG_NASAL, SG_ALERT,
529 " called from: " << naStr_data(naGetSourceFile(context, i)) <<
530 ", line " << naGetLine(context, i));
533 // Reads a script file, executes it, and places the resulting
534 // namespace into the global namespace under the specified module
536 void FGNasalSys::loadModule(SGPath file, const char* module)
539 char* buf = readfile(file.c_str(), &len);
541 SG_LOG(SG_NASAL, SG_ALERT,
542 "Nasal error: could not read script file " << file.c_str()
543 << " into module " << module);
547 createModule(module, file.c_str(), buf, len);
551 // Parse and run. Save the local variables namespace, as it will
552 // become a sub-object of globals. The optional "arg" argument can be
553 // used to pass an associated property node to the module, which can then
554 // be accessed via cmdarg(). (This is, for example, used by XML dialogs.)
555 void FGNasalSys::createModule(const char* moduleName, const char* fileName,
556 const char* src, int len, const SGPropertyNode* arg)
558 naRef code = parse(fileName, src, len);
562 // See if we already have a module hash to use. This allows the
563 // user to, for example, add functions to the built-in math
564 // module. Make a new one if necessary.
566 naRef modname = naNewString(_context);
567 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
568 if(!naHash_get(_globals, modname, &locals))
569 locals = naNewHash(_context);
571 _cmdArg = (SGPropertyNode*)arg;
574 hashset(_globals, moduleName, locals);
577 void FGNasalSys::deleteModule(const char* moduleName)
579 naRef modname = naNewString(_context);
580 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
581 naHash_delete(_globals, modname);
584 naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
587 naRef srcfile = naNewString(_context);
588 naStr_fromdata(srcfile, (char*)filename, strlen(filename));
589 naRef code = naParseCode(_context, srcfile, 1, (char*)buf, len, &errLine);
591 SG_LOG(SG_NASAL, SG_ALERT,
592 "Nasal parse error: " << naGetError(_context) <<
593 " in "<< filename <<", line " << errLine);
597 // Bind to the global namespace before returning
598 return naBindFunction(_context, code, _globals);
601 bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
603 const char* nasal = arg->getStringValue("script");
604 const char* moduleName = arg->getStringValue("module");
605 naRef code = parse(arg->getPath(true), nasal, strlen(nasal));
606 if(naIsNil(code)) return false;
608 naContext c = naNewContext();
609 naRef locals = naNil();
611 naRef modname = naNewString(c);
612 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
613 if(!naHash_get(_globals, modname, &locals))
614 locals = naNewHash(c);
616 // Cache the command argument for inspection via cmdarg(). For
617 // performance reasons, we won't bother with it if the invoked
618 // code doesn't need it.
619 _cmdArg = (SGPropertyNode*)arg;
626 // settimer(func, dt, simtime) extension function. The first argument
627 // is a Nasal function to call, the second is a delta time (from now),
628 // in seconds. The third, if present, is a boolean value indicating
629 // that "real world" time (rather than simulator time) is to be used.
631 // Implementation note: the FGTimer objects don't live inside the
632 // garbage collector, so the Nasal handler functions have to be
633 // "saved" somehow lest they be inadvertently cleaned. In this case,
634 // they are inserted into a globals.__gcsave hash and removed on
636 void FGNasalSys::setTimer(int argc, naRef* args)
638 // Extract the handler, delta, and simtime arguments:
639 naRef handler = argc > 0 ? args[0] : naNil();
640 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
643 naRef delta = argc > 1 ? args[1] : naNil();
644 if(naIsNil(delta)) return;
646 bool simtime = (argc > 2 && naTrue(args[2])) ? false : true;
648 // Generate and register a C++ timer handler
649 NasalTimer* t = new NasalTimer;
650 t->handler = handler;
651 t->gcKey = gcSave(handler);
654 globals->get_event_mgr()->addEvent("NasalTimer",
655 t, &NasalTimer::timerExpired,
659 void FGNasalSys::handleTimer(NasalTimer* t)
661 call(t->handler, naNil());
665 int FGNasalSys::gcSave(naRef r)
667 int key = _nextGCKey++;
668 naHash_set(_gcHash, naNum(key), r);
672 void FGNasalSys::gcRelease(int key)
674 naHash_delete(_gcHash, naNum(key));
677 void FGNasalSys::NasalTimer::timerExpired()
679 nasal->handleTimer(this);
683 int FGNasalSys::_listenerId = 0;
685 // setlistener(property, func, bool) extension function. The first argument
686 // is either a ghost (SGPropertyNode_ptr*) or a string (global property
687 // path), the second is a Nasal function, the optional third one a bool.
688 // If the bool is true, then the listener is executed initially. The
689 // setlistener() function returns a unique id number, that can be used
690 // as argument to the removelistener() function.
691 naRef FGNasalSys::setListener(naContext c, int argc, naRef* args)
693 SGPropertyNode_ptr node;
694 naRef prop = argc > 0 ? args[0] : naNil();
695 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
696 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
698 naRuntimeError(c, "setlistener() with invalid property argument");
703 SG_LOG(SG_NASAL, SG_DEBUG, "Attaching listener to tied property " <<
706 naRef handler = argc > 1 ? args[1] : naNil();
707 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler))) {
708 naRuntimeError(c, "setlistener() with invalid function argument");
712 bool initial = argc > 2 && naTrue(args[2]);
714 FGNasalListener *nl = new FGNasalListener(node, handler, this,
716 node->addChangeListener(nl, initial);
718 _listener[_listenerId] = nl;
719 return naNum(_listenerId++);
722 // removelistener(int) extension function. The argument is the id of
723 // a listener as returned by the setlistener() function.
724 naRef FGNasalSys::removeListener(naContext c, int argc, naRef* args)
726 naRef id = argc > 0 ? args[0] : naNil();
727 map<int, FGNasalListener *>::iterator it = _listener.find(int(id.num));
729 if(!naIsNum(id) || it == _listener.end() || it->second->_dead) {
730 naRuntimeError(c, "removelistener() with invalid listener id");
734 FGNasalListener *nl = it->second;
737 _purgeListeners = true;
743 return naNum(_listener.size());
748 // FGNasalListener class.
750 FGNasalListener::FGNasalListener(SGPropertyNode_ptr node, naRef handler,
751 FGNasalSys* nasal, int key) :
761 FGNasalListener::~FGNasalListener()
763 _node->removeChangeListener(this);
764 _nas->gcRelease(_gcKey);
767 void FGNasalListener::valueChanged(SGPropertyNode* node)
769 // drop recursive listener calls
774 _nas->_cmdArg = node;
775 _nas->call(_handler, naNil());
782 // FGNasalModelData class. If sgLoad3DModel() is called with a pointer to
783 // such a class, then it lets modelLoaded() run the <load> script, and the
784 // destructor the <unload> script. The latter happens when the model branch
785 // is removed from the scene graph.
787 void FGNasalModelData::modelLoaded(const string& path, SGPropertyNode *prop,
790 SGPropertyNode *n = prop->getNode("nasal"), *load;
794 load = n->getNode("load");
795 _unload = n->getNode("unload");
796 if(!load && !_unload)
800 const char *s = load ? load->getStringValue() : "";
801 FGNasalSys *nas = (FGNasalSys *)globals->get_subsystem("nasal");
802 nas->createModule(_module.c_str(), _module.c_str(), s, strlen(s));
805 FGNasalModelData::~FGNasalModelData()
810 FGNasalSys *nas = (FGNasalSys *)globals->get_subsystem("nasal");
812 SG_LOG(SG_NASAL, SG_ALERT, "Trying to run an <unload> script "
813 "without Nasal subsystem present.");
818 const char *s = _unload->getStringValue();
819 nas->createModule(_module.c_str(), _module.c_str(), s, strlen(s));
821 nas->deleteModule(_module.c_str());