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
62 // Does a naCall() in a new context. Wrapped here to make lock
63 // tracking easier. Extension functions are called with the lock, but
64 // we have to release it before making a new naCall(). So rather than
65 // drop the lock in every extension function that might call back into
66 // Nasal, we keep a stack depth counter here and only unlock/lock
67 // around the naCall if it isn't the first one.
68 naRef FGNasalSys::call(naRef code, naRef locals)
70 naContext ctx = naNewContext();
71 if(_callCount) naModUnlock();
73 naRef result = naCall(ctx, code, 0, 0, naNil(), locals);
77 if(_callCount) naModLock();
82 FGNasalSys::~FGNasalSys()
84 map<int, FGNasalListener *>::iterator it, end = _listener.end();
85 for (it = _listener.begin(); it != end; ++it)
88 // Nasal doesn't have a "destroy context" API yet. :(
89 // Not a problem for a global subsystem that will never be
90 // destroyed. And the context is actually a global, so no memory
91 // is technically leaked (although the GC pool memory obviously
97 bool FGNasalSys::parseAndRun(const char* sourceCode)
99 naRef code = parse("FGNasalSys::parseAndRun()", sourceCode,
107 FGNasalScript* FGNasalSys::parseScript(const char* src, const char* name)
109 FGNasalScript* script = new FGNasalScript();
110 script->_gcKey = -1; // important, if we delete it on a parse
111 script->_nas = this; // error, don't clobber a real handle!
115 sprintf(buf, "FGNasalScript@%p", script);
119 script->_code = parse(name, src, strlen(src));
120 if(naIsNil(script->_code)) {
125 script->_gcKey = gcSave(script->_code);
129 // Utility. Sets a named key in a hash by C string, rather than nasal
131 void FGNasalSys::hashset(naRef hash, const char* key, naRef val)
133 naRef s = naNewString(_context);
134 naStr_fromdata(s, (char*)key, strlen(key));
135 naHash_set(hash, s, val);
138 // The get/setprop functions accept a *list* of strings and walk
139 // through the property tree with them to find the appropriate node.
140 // This allows a Nasal object to hold onto a property path and use it
141 // like a node object, e.g. setprop(ObjRoot, "size-parsecs", 2.02). This
142 // is the utility function that walks the property tree.
143 // Future enhancement: support integer arguments to specify array
145 static SGPropertyNode* findnode(naContext c, naRef* vec, int len)
147 SGPropertyNode* p = globals->get_props();
149 for(int i=0; i<len; i++) {
151 if(!naIsString(a)) return 0;
152 p = p->getNode(naStr_data(a));
155 } catch (const string& err) {
156 naRuntimeError(c, (char *)err.c_str());
162 // getprop() extension function. Concatenates its string arguments as
163 // property names and returns the value of the specified property. Or
164 // nil if it doesn't exist.
165 static naRef f_getprop(naContext c, naRef me, int argc, naRef* args)
167 const SGPropertyNode* p = findnode(c, args, argc);
168 if(!p) return naNil();
170 switch(p->getType()) {
171 case SGPropertyNode::BOOL: case SGPropertyNode::INT:
172 case SGPropertyNode::LONG: case SGPropertyNode::FLOAT:
173 case SGPropertyNode::DOUBLE:
174 return naNum(p->getDoubleValue());
176 case SGPropertyNode::STRING:
177 case SGPropertyNode::UNSPECIFIED:
179 naRef nastr = naNewString(c);
180 const char* val = p->getStringValue();
181 naStr_fromdata(nastr, (char*)val, strlen(val));
184 case SGPropertyNode::ALIAS: // <--- FIXME, recurse?
190 // setprop() extension function. Concatenates its string arguments as
191 // property names and sets the value of the specified property to the
193 static naRef f_setprop(naContext c, naRef me, int argc, naRef* args)
196 char buf[BUFLEN + 1];
200 for(int i=0; i<argc-1; i++) {
201 naRef s = naStringValue(c, args[i]);
202 if(naIsNil(s)) return naNil();
203 strncpy(p, naStr_data(s), buflen);
205 buflen = BUFLEN - (p - buf);
206 if(i < (argc-2) && buflen > 0) {
212 SGPropertyNode* props = globals->get_props();
213 naRef val = args[argc-1];
215 if(naIsString(val)) props->setStringValue(buf, naStr_data(val));
217 naRef n = naNumValue(val);
219 naRuntimeError(c, "setprop() value is not string or number");
220 props->setDoubleValue(buf, n.num);
222 } catch (const string& err) {
223 naRuntimeError(c, (char *)err.c_str());
229 // print() extension function. Concatenates and prints its arguments
230 // to the FlightGear log. Uses the highest log level (SG_ALERT), to
231 // make sure it appears. Is there better way to do this?
232 static naRef f_print(naContext c, naRef me, int argc, naRef* args)
235 char buf[BUFLEN + 1];
236 buf[BUFLEN] = 0; // extra nul to handle strncpy brain damage
237 buf[0] = 0; // Zero-length in case there are no arguments
241 for(int i=0; i<n; i++) {
242 naRef s = naStringValue(c, args[i]);
243 if(naIsNil(s)) continue;
244 strncpy(p, naStr_data(s), buflen);
246 buflen = BUFLEN - (p - buf);
247 if(buflen <= 0) break;
249 SG_LOG(SG_GENERAL, SG_ALERT, buf);
254 // fgcommand() extension function. Executes a named command via the
255 // FlightGear command manager. Takes a single property node name as
257 static naRef f_fgcommand(naContext c, naRef me, int argc, naRef* args)
259 if(argc < 2 || !naIsString(args[0]) || !naIsGhost(args[1]))
260 naRuntimeError(c, "bad arguments to fgcommand()");
261 naRef cmd = args[0], props = args[1];
262 SGPropertyNode_ptr* node = (SGPropertyNode_ptr*)naGhost_ptr(props);
263 return naNum(globals->get_commands()->execute(naStr_data(cmd), *node));
266 // settimer(func, dt, simtime) extension function. Falls through to
267 // FGNasalSys::setTimer(). See there for docs.
268 static naRef f_settimer(naContext c, naRef me, int argc, naRef* args)
270 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
271 nasal->setTimer(argc, args);
275 // setlistener(func, property, bool) extension function. Falls through to
276 // FGNasalSys::setListener(). See there for docs.
277 static naRef f_setlistener(naContext c, naRef me, int argc, naRef* args)
279 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
280 return nasal->setListener(argc, args);
283 // removelistener(int) extension function. Falls through to
284 // FGNasalSys::removeListener(). See there for docs.
285 static naRef f_removelistener(naContext c, naRef me, int argc, naRef* args)
287 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
288 return nasal->removeListener(c, argc, args);
291 // Returns a ghost handle to the argument to the currently executing
293 static naRef f_cmdarg(naContext c, naRef me, int argc, naRef* args)
295 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
296 return nasal->cmdArgGhost();
299 // Sets up a property interpolation. The first argument is either a
300 // ghost (SGPropertyNode_ptr*) or a string (global property path) to
301 // interpolate. The second argument is a vector of pairs of
302 // value/delta numbers.
303 static naRef f_interpolate(naContext c, naRef me, int argc, naRef* args)
305 SGPropertyNode* node;
306 naRef prop = argc > 0 ? args[0] : naNil();
307 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
308 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
311 naRef curve = argc > 1 ? args[1] : naNil();
312 if(!naIsVector(curve)) return naNil();
313 int nPoints = naVec_size(curve) / 2;
314 double* values = new double[nPoints];
315 double* deltas = new double[nPoints];
316 for(int i=0; i<nPoints; i++) {
317 values[i] = naNumValue(naVec_get(curve, 2*i)).num;
318 deltas[i] = naNumValue(naVec_get(curve, 2*i+1)).num;
321 ((SGInterpolator*)globals->get_subsystem("interpolator"))
322 ->interpolate(node, nPoints, values, deltas);
327 // This is a better RNG than the one in the default Nasal distribution
328 // (which is based on the C library rand() implementation). It will
330 static naRef f_rand(naContext c, naRef me, int argc, naRef* args)
332 return naNum(sg_random());
335 static naRef f_srand(naContext c, naRef me, int argc, naRef* args)
341 // Return an array listing of all files in a directory
342 static naRef f_directory(naContext c, naRef me, int argc, naRef* args)
344 if(argc != 1 || !naIsString(args[0]))
345 naRuntimeError(c, "bad arguments to directory()");
346 naRef ldir = args[0];
347 ulDir* dir = ulOpenDir(naStr_data(args[0]));
348 if(!dir) return naNil();
349 naRef result = naNewVector(c);
351 while((dent = ulReadDir(dir)))
352 naVec_append(result, naStr_fromdata(naNewString(c), dent->d_name,
353 strlen(dent->d_name)));
358 // Table of extension functions. Terminate with zeros.
359 static struct { char* name; naCFunction func; } funcs[] = {
360 { "getprop", f_getprop },
361 { "setprop", f_setprop },
362 { "print", f_print },
363 { "_fgcommand", f_fgcommand },
364 { "settimer", f_settimer },
365 { "_setlistener", f_setlistener },
366 { "removelistener", f_removelistener },
367 { "_cmdarg", f_cmdarg },
368 { "_interpolate", f_interpolate },
370 { "srand", f_srand },
371 { "directory", f_directory },
375 naRef FGNasalSys::cmdArgGhost()
377 return propNodeGhost(_cmdArg);
380 void FGNasalSys::init()
384 _context = naNewContext();
386 // Start with globals. Add it to itself as a recursive
387 // sub-reference under the name "globals". This gives client-code
388 // write access to the namespace if someone wants to do something
390 _globals = naStdLib(_context);
391 naSave(_context, _globals);
392 hashset(_globals, "globals", _globals);
394 // Add in the math library under "math"
395 hashset(_globals, "math", naMathLib(_context));
397 // Add in the IO library. Disabled currently until after the
399 // hashset(_globals, "io", naIOLib(_context));
400 // hashset(_globals, "bits", naBitsLib(_context));
402 // Add our custom extension functions:
403 for(i=0; funcs[i].name; i++)
404 hashset(_globals, funcs[i].name,
405 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
407 // And our SGPropertyNode wrapper
408 hashset(_globals, "props", genPropsModule());
410 // Make a "__gcsave" hash to hold the naRef objects which get
411 // passed to handles outside the interpreter (to protect them from
412 // begin garbage-collected).
413 _gcHash = naNewHash(_context);
414 hashset(_globals, "__gcsave", _gcHash);
416 // Now load the various source files in the Nasal directory
417 SGPath p(globals->get_fg_root());
420 ulDir* dir = ulOpenDir(p.c_str());
421 while(dir && (dent = ulReadDir(dir)) != 0) {
423 fullpath.append(dent->d_name);
424 SGPath file(dent->d_name);
425 if(file.extension() != "nas") continue;
426 loadModule(fullpath, file.base().c_str());
429 fgSetBool("/sim/signals/nasal-dir-initialized", true);
431 // Pull scripts out of the property tree, too
432 loadPropertyScripts();
435 // Loads the scripts found under /nasal in the global tree
436 void FGNasalSys::loadPropertyScripts()
438 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
441 for(int i=0; i<nasal->nChildren(); i++) {
442 SGPropertyNode* n = nasal->getChild(i);
444 const char* module = n->getName();
445 if(n->hasChild("module"))
446 module = n->getStringValue("module");
448 // allow multiple files to be specified within in a single
452 bool file_specified = false;
453 while ( (fn = n->getChild("file", j)) != NULL ) {
454 file_specified = true;
455 const char* file = fn->getStringValue();
456 SGPath p(globals->get_fg_root());
458 loadModule(p, module);
462 // Old code which only allowed a single file to be specified per module
464 const char* file = n->getStringValue("file");
465 if(!n->hasChild("file")) file = 0; // Hrm...
467 SGPath p(globals->get_fg_root());
469 loadModule(p, module);
473 const char* src = n->getStringValue("script");
474 if(!n->hasChild("script")) src = 0; // Hrm...
476 createModule(module, n->getPath(), src, strlen(src));
478 if(!file_specified && !src)
479 SG_LOG(SG_NASAL, SG_ALERT, "Nasal error: " <<
480 "no <file> or <script> defined in " <<
481 "/nasal/" << module);
485 // Logs a runtime error, with stack trace, to the FlightGear log stream
486 void FGNasalSys::logError(naContext context)
488 SG_LOG(SG_NASAL, SG_ALERT,
489 "Nasal runtime error: " << naGetError(context));
490 SG_LOG(SG_NASAL, SG_ALERT,
491 " at " << naStr_data(naGetSourceFile(context, 0)) <<
492 ", line " << naGetLine(context, 0));
493 for(int i=1; i<naStackDepth(context); i++)
494 SG_LOG(SG_NASAL, SG_ALERT,
495 " called from: " << naStr_data(naGetSourceFile(context, i)) <<
496 ", line " << naGetLine(context, i));
499 // Reads a script file, executes it, and places the resulting
500 // namespace into the global namespace under the specified module
502 void FGNasalSys::loadModule(SGPath file, const char* module)
505 char* buf = readfile(file.c_str(), &len);
507 SG_LOG(SG_NASAL, SG_ALERT,
508 "Nasal error: could not read script file " << file.c_str()
509 << " into module " << module);
513 createModule(module, file.c_str(), buf, len);
517 // Parse and run. Save the local variables namespace, as it will
518 // become a sub-object of globals. The optional "arg" argument can be
519 // used to pass an associated property node to the module, which can then
520 // be accessed via cmdarg(). (This is, for example, used by XML dialogs.)
521 void FGNasalSys::createModule(const char* moduleName, const char* fileName,
522 const char* src, int len, const SGPropertyNode* arg)
524 naRef code = parse(fileName, src, len);
528 // See if we already have a module hash to use. This allows the
529 // user to, for example, add functions to the built-in math
530 // module. Make a new one if necessary.
532 naRef modname = naNewString(_context);
533 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
534 if(!naHash_get(_globals, modname, &locals))
535 locals = naNewHash(_context);
537 _cmdArg = (SGPropertyNode*)arg;
540 hashset(_globals, moduleName, locals);
543 void FGNasalSys::deleteModule(const char* moduleName)
545 naRef modname = naNewString(_context);
546 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
547 naHash_delete(_globals, modname);
550 naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
553 naRef srcfile = naNewString(_context);
554 naStr_fromdata(srcfile, (char*)filename, strlen(filename));
555 naRef code = naParseCode(_context, srcfile, 1, (char*)buf, len, &errLine);
557 SG_LOG(SG_NASAL, SG_ALERT,
558 "Nasal parse error: " << naGetError(_context) <<
559 " in "<< filename <<", line " << errLine);
563 // Bind to the global namespace before returning
564 return naBindFunction(_context, code, _globals);
567 bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
569 const char* nasal = arg->getStringValue("script");
570 const char* moduleName = arg->getStringValue("module");
571 naRef code = parse(arg->getPath(true), nasal, strlen(nasal));
572 if(naIsNil(code)) return false;
574 naContext c = naNewContext();
575 naRef locals = naNil();
577 naRef modname = naNewString(c);
578 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
579 if(!naHash_get(_globals, modname, &locals))
580 locals = naNewHash(c);
582 // Cache the command argument for inspection via cmdarg(). For
583 // performance reasons, we won't bother with it if the invoked
584 // code doesn't need it.
585 _cmdArg = (SGPropertyNode*)arg;
592 // settimer(func, dt, simtime) extension function. The first argument
593 // is a Nasal function to call, the second is a delta time (from now),
594 // in seconds. The third, if present, is a boolean value indicating
595 // that "real world" time (rather than simulator time) is to be used.
597 // Implementation note: the FGTimer objects don't live inside the
598 // garbage collector, so the Nasal handler functions have to be
599 // "saved" somehow lest they be inadvertently cleaned. In this case,
600 // they are inserted into a globals.__gcsave hash and removed on
602 void FGNasalSys::setTimer(int argc, naRef* args)
604 // Extract the handler, delta, and simtime arguments:
605 naRef handler = argc > 0 ? args[0] : naNil();
606 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
609 naRef delta = argc > 1 ? args[1] : naNil();
610 if(naIsNil(delta)) return;
612 bool simtime = (argc > 2 && naTrue(args[2])) ? false : true;
614 // Generate and register a C++ timer handler
615 NasalTimer* t = new NasalTimer;
616 t->handler = handler;
617 t->gcKey = gcSave(handler);
620 globals->get_event_mgr()->addEvent("NasalTimer",
621 t, &NasalTimer::timerExpired,
625 void FGNasalSys::handleTimer(NasalTimer* t)
627 call(t->handler, naNil());
631 int FGNasalSys::gcSave(naRef r)
633 int key = _nextGCKey++;
634 naHash_set(_gcHash, naNum(key), r);
638 void FGNasalSys::gcRelease(int key)
640 naHash_delete(_gcHash, naNum(key));
643 void FGNasalSys::NasalTimer::timerExpired()
645 nasal->handleTimer(this);
649 int FGNasalSys::_listenerId = 0;
651 // setlistener(property, func, bool) extension function. The first argument
652 // is either a ghost (SGPropertyNode_ptr*) or a string (global property
653 // path), the second is a Nasal function, the optional third one a bool.
654 // If the bool is true, then the listener is executed initially. The
655 // setlistener() function returns a unique id number, that can be used
656 // as argument to the removelistener() function.
657 naRef FGNasalSys::setListener(int argc, naRef* args)
659 SGPropertyNode_ptr node;
660 naRef prop = argc > 0 ? args[0] : naNil();
661 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
662 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
666 SG_LOG(SG_NASAL, SG_DEBUG, "Attaching listener to tied property " <<
669 naRef handler = argc > 1 ? args[1] : naNil();
670 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
673 bool initial = argc > 2 && naTrue(args[2]);
675 FGNasalListener *nl = new FGNasalListener(node, handler, this,
677 node->addChangeListener(nl, initial);
679 _listener[_listenerId] = nl;
680 return naNum(_listenerId++);
683 // removelistener(int) extension function. The argument is the id of
684 // a listener as returned by the setlistener() function.
685 naRef FGNasalSys::removeListener(naContext c, int argc, naRef* args)
687 naRef id = argc > 0 ? args[0] : naNil();
690 if(!naIsNum(id) || _listener.find(i) == _listener.end()) {
691 naRuntimeError(c, "removelistener() with invalid listener id");
695 FGNasalListener *nl = _listener[i];
697 naRuntimeError(c, "trying to remove active listener");
703 return naNum(_listener.size());
708 // FGNasalListener class.
710 FGNasalListener::FGNasalListener(SGPropertyNode_ptr node, naRef handler,
711 FGNasalSys* nasal, int key) :
720 FGNasalListener::~FGNasalListener()
722 _node->removeChangeListener(this);
723 _nas->gcRelease(_gcKey);
726 void FGNasalListener::valueChanged(SGPropertyNode* node)
728 // drop recursive listener calls
733 _nas->_cmdArg = node;
734 _nas->call(_handler, naNil());
741 // FGNasalModelData class. If sgLoad3DModel() is called with a pointer to
742 // such a class, then it lets modelLoaded() run the <load> script, and the
743 // destructor the <unload> script. The latter happens when the model branch
744 // is removed from the scene graph.
746 void FGNasalModelData::modelLoaded(const string& path, SGPropertyNode *prop,
749 SGPropertyNode *n = prop->getNode("nasal"), *load;
753 load = n->getNode("load");
754 _unload = n->getNode("unload");
755 if (!load && !_unload)
759 const char *s = load ? load->getStringValue() : "";
760 FGNasalSys *nas = (FGNasalSys *)globals->get_subsystem("nasal");
761 nas->createModule(_module.c_str(), _module.c_str(), s, strlen(s));
764 FGNasalModelData::~FGNasalModelData()
769 FGNasalSys *nas = (FGNasalSys *)globals->get_subsystem("nasal");
771 SG_LOG(SG_NASAL, SG_ALERT, "Trying to run an <unload> script "
772 "without Nasal subsystem present.");
777 const char *s = _unload->getStringValue();
778 nas->createModule(_module.c_str(), _module.c_str(), s, strlen(s));
780 nas->deleteModule(_module.c_str());