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));
216 else props->setDoubleValue(buf, naNumValue(val).num);
217 } catch (const string& err) {
218 naRuntimeError(c, (char *)err.c_str());
224 // print() extension function. Concatenates and prints its arguments
225 // to the FlightGear log. Uses the highest log level (SG_ALERT), to
226 // make sure it appears. Is there better way to do this?
227 static naRef f_print(naContext c, naRef me, int argc, naRef* args)
230 char buf[BUFLEN + 1];
231 buf[BUFLEN] = 0; // extra nul to handle strncpy brain damage
232 buf[0] = 0; // Zero-length in case there are no arguments
236 for(int i=0; i<n; i++) {
237 naRef s = naStringValue(c, args[i]);
238 if(naIsNil(s)) continue;
239 strncpy(p, naStr_data(s), buflen);
241 buflen = BUFLEN - (p - buf);
242 if(buflen <= 0) break;
244 SG_LOG(SG_GENERAL, SG_ALERT, buf);
249 // fgcommand() extension function. Executes a named command via the
250 // FlightGear command manager. Takes a single property node name as
252 static naRef f_fgcommand(naContext c, naRef me, int argc, naRef* args)
254 if(argc < 2 || !naIsString(args[0]) || !naIsGhost(args[1]))
255 naRuntimeError(c, "bad arguments to fgcommand()");
256 naRef cmd = args[0], props = args[1];
257 SGPropertyNode_ptr* node = (SGPropertyNode_ptr*)naGhost_ptr(props);
258 globals->get_commands()->execute(naStr_data(cmd), *node);
263 // settimer(func, dt, simtime) extension function. Falls through to
264 // FGNasalSys::setTimer(). See there for docs.
265 static naRef f_settimer(naContext c, naRef me, int argc, naRef* args)
267 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
268 nasal->setTimer(argc, args);
272 // setlistener(func, property, bool) extension function. Falls through to
273 // FGNasalSys::setListener(). See there for docs.
274 static naRef f_setlistener(naContext c, naRef me, int argc, naRef* args)
276 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
277 return nasal->setListener(argc, args);
280 // removelistener(int) extension function. Falls through to
281 // FGNasalSys::removeListener(). See there for docs.
282 static naRef f_removelistener(naContext c, naRef me, int argc, naRef* args)
284 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
285 return nasal->removeListener(argc, args);
288 // Returns a ghost handle to the argument to the currently executing
290 static naRef f_cmdarg(naContext c, naRef me, int argc, naRef* args)
292 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
293 return nasal->cmdArgGhost();
296 // Sets up a property interpolation. The first argument is either a
297 // ghost (SGPropertyNode_ptr*) or a string (global property path) to
298 // interpolate. The second argument is a vector of pairs of
299 // value/delta numbers.
300 static naRef f_interpolate(naContext c, naRef me, int argc, naRef* args)
302 SGPropertyNode* node;
303 naRef prop = argc > 0 ? args[0] : naNil();
304 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
305 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
308 naRef curve = argc > 1 ? args[1] : naNil();
309 if(!naIsVector(curve)) return naNil();
310 int nPoints = naVec_size(curve) / 2;
311 double* values = new double[nPoints];
312 double* deltas = new double[nPoints];
313 for(int i=0; i<nPoints; i++) {
314 values[i] = naNumValue(naVec_get(curve, 2*i)).num;
315 deltas[i] = naNumValue(naVec_get(curve, 2*i+1)).num;
318 ((SGInterpolator*)globals->get_subsystem("interpolator"))
319 ->interpolate(node, nPoints, values, deltas);
324 // This is a better RNG than the one in the default Nasal distribution
325 // (which is based on the C library rand() implementation). It will
327 static naRef f_rand(naContext c, naRef me, int argc, naRef* args)
329 return naNum(sg_random());
332 static naRef f_srand(naContext c, naRef me, int argc, naRef* args)
338 // Return an array listing of all files in a directory
339 static naRef f_directory(naContext c, naRef me, int argc, naRef* args)
341 if(argc != 1 || !naIsString(args[0]))
342 naRuntimeError(c, "bad arguments to directory()");
343 naRef ldir = args[0];
344 ulDir* dir = ulOpenDir(naStr_data(args[0]));
345 if(!dir) return naNil();
346 naRef result = naNewVector(c);
348 while((dent = ulReadDir(dir)))
349 naVec_append(result, naStr_fromdata(naNewString(c), dent->d_name,
350 strlen(dent->d_name)));
355 // Table of extension functions. Terminate with zeros.
356 static struct { char* name; naCFunction func; } funcs[] = {
357 { "getprop", f_getprop },
358 { "setprop", f_setprop },
359 { "print", f_print },
360 { "_fgcommand", f_fgcommand },
361 { "settimer", f_settimer },
362 { "_setlistener", f_setlistener },
363 { "removelistener", f_removelistener },
364 { "_cmdarg", f_cmdarg },
365 { "_interpolate", f_interpolate },
367 { "srand", f_srand },
368 { "directory", f_directory },
372 naRef FGNasalSys::cmdArgGhost()
374 return propNodeGhost(_cmdArg);
377 void FGNasalSys::init()
381 _context = naNewContext();
383 // Start with globals. Add it to itself as a recursive
384 // sub-reference under the name "globals". This gives client-code
385 // write access to the namespace if someone wants to do something
387 _globals = naStdLib(_context);
388 naSave(_context, _globals);
389 hashset(_globals, "globals", _globals);
391 // Add in the math library under "math"
392 hashset(_globals, "math", naMathLib(_context));
394 // Add in the IO library. Disabled currently until after the
396 // hashset(_globals, "io", naIOLib(_context));
397 // hashset(_globals, "bits", naBitsLib(_context));
399 // Add our custom extension functions:
400 for(i=0; funcs[i].name; i++)
401 hashset(_globals, funcs[i].name,
402 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
404 // And our SGPropertyNode wrapper
405 hashset(_globals, "props", genPropsModule());
407 // Make a "__gcsave" hash to hold the naRef objects which get
408 // passed to handles outside the interpreter (to protect them from
409 // begin garbage-collected).
410 _gcHash = naNewHash(_context);
411 hashset(_globals, "__gcsave", _gcHash);
413 // Now load the various source files in the Nasal directory
414 SGPath p(globals->get_fg_root());
417 ulDir* dir = ulOpenDir(p.c_str());
418 while(dir && (dent = ulReadDir(dir)) != 0) {
420 fullpath.append(dent->d_name);
421 SGPath file(dent->d_name);
422 if(file.extension() != "nas") continue;
423 loadModule(fullpath, file.base().c_str());
427 // Pull scripts out of the property tree, too
428 loadPropertyScripts();
431 // Loads the scripts found under /nasal in the global tree
432 void FGNasalSys::loadPropertyScripts()
434 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
437 for(int i=0; i<nasal->nChildren(); i++) {
438 SGPropertyNode* n = nasal->getChild(i);
440 const char* module = n->getName();
441 if(n->hasChild("module"))
442 module = n->getStringValue("module");
444 // allow multiple files to be specified within in a single
448 bool file_specified = false;
449 while ( (fn = n->getChild("file", j)) != NULL ) {
450 file_specified = true;
451 const char* file = fn->getStringValue();
452 SGPath p(globals->get_fg_root());
454 loadModule(p, module);
458 // Old code which only allowed a single file to be specified per module
460 const char* file = n->getStringValue("file");
461 if(!n->hasChild("file")) file = 0; // Hrm...
463 SGPath p(globals->get_fg_root());
465 loadModule(p, module);
469 const char* src = n->getStringValue("script");
470 if(!n->hasChild("script")) src = 0; // Hrm...
472 createModule(module, n->getPath(), src, strlen(src));
474 if(!file_specified && !src)
475 SG_LOG(SG_NASAL, SG_ALERT, "Nasal error: " <<
476 "no <file> or <script> defined in " <<
477 "/nasal/" << module);
481 // Logs a runtime error, with stack trace, to the FlightGear log stream
482 void FGNasalSys::logError(naContext context)
484 SG_LOG(SG_NASAL, SG_ALERT,
485 "Nasal runtime error: " << naGetError(context));
486 SG_LOG(SG_NASAL, SG_ALERT,
487 " at " << naStr_data(naGetSourceFile(context, 0)) <<
488 ", line " << naGetLine(context, 0));
489 for(int i=1; i<naStackDepth(context); i++)
490 SG_LOG(SG_NASAL, SG_ALERT,
491 " called from: " << naStr_data(naGetSourceFile(context, i)) <<
492 ", line " << naGetLine(context, i));
495 // Reads a script file, executes it, and places the resulting
496 // namespace into the global namespace under the specified module
498 void FGNasalSys::loadModule(SGPath file, const char* module)
501 char* buf = readfile(file.c_str(), &len);
503 SG_LOG(SG_NASAL, SG_ALERT,
504 "Nasal error: could not read script file " << file.c_str()
505 << " into module " << module);
509 createModule(module, file.c_str(), buf, len);
513 // Parse and run. Save the local variables namespace, as it will
514 // become a sub-object of globals. The optional "arg" argument can be
515 // used to pass an associated property node to the module, which can then
516 // be accessed via cmdarg(). (This is, for example, used by XML dialogs.)
517 void FGNasalSys::createModule(const char* moduleName, const char* fileName,
518 const char* src, int len, const SGPropertyNode* arg)
520 naRef code = parse(fileName, src, len);
524 // See if we already have a module hash to use. This allows the
525 // user to, for example, add functions to the built-in math
526 // module. Make a new one if necessary.
528 naRef modname = naNewString(_context);
529 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
530 if(!naHash_get(_globals, modname, &locals))
531 locals = naNewHash(_context);
533 _cmdArg = (SGPropertyNode*)arg;
536 hashset(_globals, moduleName, locals);
539 void FGNasalSys::deleteModule(const char* moduleName)
541 naRef modname = naNewString(_context);
542 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
543 naHash_delete(_globals, modname);
546 naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
549 naRef srcfile = naNewString(_context);
550 naStr_fromdata(srcfile, (char*)filename, strlen(filename));
551 naRef code = naParseCode(_context, srcfile, 1, (char*)buf, len, &errLine);
553 SG_LOG(SG_NASAL, SG_ALERT,
554 "Nasal parse error: " << naGetError(_context) <<
555 " in "<< filename <<", line " << errLine);
559 // Bind to the global namespace before returning
560 return naBindFunction(_context, code, _globals);
563 bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
565 const char* nasal = arg->getStringValue("script");
566 const char* moduleName = arg->getStringValue("module");
567 naRef code = parse(arg->getPath(true), nasal, strlen(nasal));
568 if(naIsNil(code)) return false;
570 naContext c = naNewContext();
571 naRef locals = naNil();
573 naRef modname = naNewString(c);
574 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
575 if(!naHash_get(_globals, modname, &locals))
576 locals = naNewHash(c);
578 // Cache the command argument for inspection via cmdarg(). For
579 // performance reasons, we won't bother with it if the invoked
580 // code doesn't need it.
581 _cmdArg = (SGPropertyNode*)arg;
588 // settimer(func, dt, simtime) extension function. The first argument
589 // is a Nasal function to call, the second is a delta time (from now),
590 // in seconds. The third, if present, is a boolean value indicating
591 // that "real world" time (rather than simulator time) is to be used.
593 // Implementation note: the FGTimer objects don't live inside the
594 // garbage collector, so the Nasal handler functions have to be
595 // "saved" somehow lest they be inadvertently cleaned. In this case,
596 // they are inserted into a globals.__gcsave hash and removed on
598 void FGNasalSys::setTimer(int argc, naRef* args)
600 // Extract the handler, delta, and simtime arguments:
601 naRef handler = argc > 0 ? args[0] : naNil();
602 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
605 naRef delta = argc > 1 ? args[1] : naNil();
606 if(naIsNil(delta)) return;
608 bool simtime = (argc > 2 && naTrue(args[2])) ? false : true;
610 // Generate and register a C++ timer handler
611 NasalTimer* t = new NasalTimer;
612 t->handler = handler;
613 t->gcKey = gcSave(handler);
616 globals->get_event_mgr()->addEvent("NasalTimer",
617 t, &NasalTimer::timerExpired,
621 void FGNasalSys::handleTimer(NasalTimer* t)
623 call(t->handler, naNil());
627 int FGNasalSys::gcSave(naRef r)
629 int key = _nextGCKey++;
630 naHash_set(_gcHash, naNum(key), r);
634 void FGNasalSys::gcRelease(int key)
636 naHash_delete(_gcHash, naNum(key));
639 void FGNasalSys::NasalTimer::timerExpired()
641 nasal->handleTimer(this);
645 int FGNasalSys::_listenerId = 0;
647 // setlistener(property, func, bool) extension function. The first argument
648 // is either a ghost (SGPropertyNode_ptr*) or a string (global property
649 // path), the second is a Nasal function, the optional third one a bool.
650 // If the bool is true, then the listener is executed initially. The
651 // setlistener() function returns a unique id number, that can be used
652 // as argument to the removelistener() function.
653 naRef FGNasalSys::setListener(int argc, naRef* args)
655 SGPropertyNode_ptr node;
656 naRef prop = argc > 0 ? args[0] : naNil();
657 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
658 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
662 SG_LOG(SG_NASAL, SG_DEBUG, "Attaching listener to tied property " <<
665 naRef handler = argc > 1 ? args[1] : naNil();
666 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
669 bool initial = argc > 2 && naTrue(args[2]);
671 FGNasalListener *nl = new FGNasalListener(node, handler, this,
673 node->addChangeListener(nl, initial);
675 _listener[_listenerId] = nl;
676 return naNum(_listenerId++);
679 // removelistener(int) extension function. The argument is the id of
680 // a listener as returned by the setlistener() function.
681 naRef FGNasalSys::removeListener(int argc, naRef* args)
683 naRef id = argc > 0 ? args[0] : naNil();
688 if (_listener.find(i) == _listener.end())
691 FGNasalListener *nl = _listener[i];
694 return naNum(_listener.size());
699 // FGNasalListener class.
701 FGNasalListener::FGNasalListener(SGPropertyNode_ptr node, naRef handler,
702 FGNasalSys* nasal, int key) :
711 FGNasalListener::~FGNasalListener()
713 _node->removeChangeListener(this);
714 _nas->gcRelease(_gcKey);
717 void FGNasalListener::valueChanged(SGPropertyNode* node)
719 // drop recursive listener calls
724 _nas->_cmdArg = node;
725 _nas->call(_handler, naNil());
732 // FGNasalModelData class. If sgLoad3DModel() is called with a pointer to
733 // such a class, then it lets modelLoaded() run the <load> script, and the
734 // destructor the <unload> script. The latter happens when the model branch
735 // is removed from the scene graph.
737 void FGNasalModelData::modelLoaded(const string& path, SGPropertyNode *prop,
740 SGPropertyNode *n = prop->getNode("nasal"), *load;
744 load = n->getNode("load");
745 _unload = n->getNode("unload");
746 if (!load && !_unload)
750 const char *s = load ? load->getStringValue() : "";
751 FGNasalSys *nas = (FGNasalSys *)globals->get_subsystem("nasal");
752 nas->createModule(_module.c_str(), _module.c_str(), s, strlen(s));
755 FGNasalModelData::~FGNasalModelData()
760 FGNasalSys *nas = (FGNasalSys *)globals->get_subsystem("nasal");
762 SG_LOG(SG_NASAL, SG_ALERT, "Trying to run an <unload> script "
763 "without Nasal subsystem present.");
768 const char *s = _unload->getStringValue();
769 nas->createModule(_module.c_str(), _module.c_str(), s, strlen(s));
771 nas->deleteModule(_module.c_str());