7 # include <sys/time.h> // gettimeofday
12 #include <sys/types.h>
16 #include <algorithm> // for std::sort
18 #include <simgear/nasal/nasal.h>
19 #include <simgear/props/props.hxx>
20 #include <simgear/math/sg_random.h>
21 #include <simgear/misc/sg_path.hxx>
22 #include <simgear/misc/sg_dir.hxx>
23 #include <simgear/misc/interpolator.hxx>
24 #include <simgear/structure/commands.hxx>
25 #include <simgear/math/sg_geodesy.hxx>
26 #include <simgear/structure/event_mgr.hxx>
28 #include "NasalSys.hxx"
29 #include "NasalPositioned.hxx"
30 #include <Main/globals.hxx>
31 #include <Main/util.hxx>
32 #include <Main/fg_props.hxx>
36 static FGNasalSys* nasalSys = 0;
38 // Listener class for loading Nasal modules on demand
39 class FGNasalModuleListener : public SGPropertyChangeListener
42 FGNasalModuleListener(SGPropertyNode* node);
44 virtual void valueChanged(SGPropertyNode* node);
47 SGPropertyNode_ptr _node;
50 FGNasalModuleListener::FGNasalModuleListener(SGPropertyNode* node) : _node(node)
54 void FGNasalModuleListener::valueChanged(SGPropertyNode*)
56 if (_node->getBoolValue("enabled",false)&&
57 !_node->getBoolValue("loaded",true))
59 nasalSys->loadPropertyScripts(_node);
64 // Read and return file contents in a single buffer. Note use of
65 // stat() to get the file size. This is a win32 function, believe it
66 // or not. :) Note the REALLY IMPORTANT use of the "b" flag to fopen.
67 // Text mode brain damage will kill us if we're trying to do bytewise
69 static char* readfile(const char* file, int* lenOut)
72 if(stat(file, &data) != 0) return 0;
73 FILE* f = fopen(file, "rb");
75 char* buf = new char[data.st_size];
76 *lenOut = fread(buf, 1, data.st_size, f);
78 if(*lenOut != data.st_size) {
79 // Shouldn't happen, but warn anyway since it represents a
80 // platform bug and not a typical runtime error (missing file,
82 SG_LOG(SG_NASAL, SG_ALERT,
83 "ERROR in Nasal initialization: " <<
84 "short count returned from fread() of " << file <<
85 ". Check your C library!");
92 FGNasalSys::FGNasalSys()
98 _nextGCKey = 0; // Any value will do
102 naRef FGNasalSys::call(naRef code, int argc, naRef* args, naRef locals)
104 return callMethod(code, naNil(), argc, args, locals);
107 // Does a naCall() in a new context. Wrapped here to make lock
108 // tracking easier. Extension functions are called with the lock, but
109 // we have to release it before making a new naCall(). So rather than
110 // drop the lock in every extension function that might call back into
111 // Nasal, we keep a stack depth counter here and only unlock/lock
112 // around the naCall if it isn't the first one.
114 naRef FGNasalSys::callMethod(naRef code, naRef self, int argc, naRef* args, naRef locals)
116 naContext ctx = naNewContext();
117 if(_callCount) naModUnlock();
119 naRef result = naCall(ctx, code, argc, args, self, locals);
123 if(_callCount) naModLock();
128 FGNasalSys::~FGNasalSys()
131 map<int, FGNasalListener *>::iterator it, end = _listener.end();
132 for(it = _listener.begin(); it != end; ++it)
135 naFreeContext(_context);
139 bool FGNasalSys::parseAndRun(const char* sourceCode)
141 naRef code = parse("FGNasalSys::parseAndRun()", sourceCode,
145 call(code, 0, 0, naNil());
149 FGNasalScript* FGNasalSys::parseScript(const char* src, const char* name)
151 FGNasalScript* script = new FGNasalScript();
152 script->_gcKey = -1; // important, if we delete it on a parse
153 script->_nas = this; // error, don't clobber a real handle!
157 sprintf(buf, "FGNasalScript@%p", (void *)script);
161 script->_code = parse(name, src, strlen(src));
162 if(naIsNil(script->_code)) {
167 script->_gcKey = gcSave(script->_code);
171 // Utility. Sets a named key in a hash by C string, rather than nasal
173 void FGNasalSys::hashset(naRef hash, const char* key, naRef val)
175 naRef s = naNewString(_context);
176 naStr_fromdata(s, (char*)key, strlen(key));
177 naHash_set(hash, s, val);
180 // The get/setprop functions accept a *list* of strings and walk
181 // through the property tree with them to find the appropriate node.
182 // This allows a Nasal object to hold onto a property path and use it
183 // like a node object, e.g. setprop(ObjRoot, "size-parsecs", 2.02). This
184 // is the utility function that walks the property tree.
185 // Future enhancement: support integer arguments to specify array
187 static SGPropertyNode* findnode(naContext c, naRef* vec, int len)
189 SGPropertyNode* p = globals->get_props();
191 for(int i=0; i<len; i++) {
193 if(!naIsString(a)) return 0;
194 p = p->getNode(naStr_data(a));
197 } catch (const string& err) {
198 naRuntimeError(c, (char *)err.c_str());
204 // getprop() extension function. Concatenates its string arguments as
205 // property names and returns the value of the specified property. Or
206 // nil if it doesn't exist.
207 static naRef f_getprop(naContext c, naRef me, int argc, naRef* args)
209 using namespace simgear;
210 const SGPropertyNode* p = findnode(c, args, argc);
211 if(!p) return naNil();
213 switch(p->getType()) {
214 case props::BOOL: case props::INT:
215 case props::LONG: case props::FLOAT:
218 double dv = p->getDoubleValue();
219 if (osg::isNaN(dv)) {
220 SG_LOG(SG_NASAL, SG_ALERT, "Nasal getprop: property " << p->getPath() << " is NaN");
228 case props::UNSPECIFIED:
230 naRef nastr = naNewString(c);
231 const char* val = p->getStringValue();
232 naStr_fromdata(nastr, (char*)val, strlen(val));
235 case props::ALIAS: // <--- FIXME, recurse?
241 // setprop() extension function. Concatenates its string arguments as
242 // property names and sets the value of the specified property to the
244 static naRef f_setprop(naContext c, naRef me, int argc, naRef* args)
247 char buf[BUFLEN + 1];
251 if(argc < 2) naRuntimeError(c, "setprop() expects at least 2 arguments");
252 for(int i=0; i<argc-1; i++) {
253 naRef s = naStringValue(c, args[i]);
254 if(naIsNil(s)) return naNil();
255 strncpy(p, naStr_data(s), buflen);
257 buflen = BUFLEN - (p - buf);
258 if(i < (argc-2) && buflen > 0) {
264 SGPropertyNode* props = globals->get_props();
265 naRef val = args[argc-1];
268 if(naIsString(val)) result = props->setStringValue(buf, naStr_data(val));
270 naRef n = naNumValue(val);
272 naRuntimeError(c, "setprop() value is not string or number");
274 if (osg::isNaN(n.num)) {
275 naRuntimeError(c, "setprop() passed a NaN");
278 result = props->setDoubleValue(buf, n.num);
280 } catch (const string& err) {
281 naRuntimeError(c, (char *)err.c_str());
283 return naNum(result);
287 // print() extension function. Concatenates and prints its arguments
288 // to the FlightGear log. Uses the highest log level (SG_ALERT), to
289 // make sure it appears. Is there better way to do this?
290 static naRef f_print(naContext c, naRef me, int argc, naRef* args)
294 for(int i=0; i<n; i++) {
295 naRef s = naStringValue(c, args[i]);
296 if(naIsNil(s)) continue;
297 buf += naStr_data(s);
299 SG_LOG(SG_NASAL, SG_ALERT, buf);
300 return naNum(buf.length());
303 // fgcommand() extension function. Executes a named command via the
304 // FlightGear command manager. Takes a single property node name as
306 static naRef f_fgcommand(naContext c, naRef me, int argc, naRef* args)
308 naRef cmd = argc > 0 ? args[0] : naNil();
309 naRef props = argc > 1 ? args[1] : naNil();
310 if(!naIsString(cmd) || (!naIsNil(props) && !naIsGhost(props)))
311 naRuntimeError(c, "bad arguments to fgcommand()");
312 SGPropertyNode_ptr tmp, *node;
314 node = (SGPropertyNode_ptr*)naGhost_ptr(props);
316 tmp = new SGPropertyNode();
319 return naNum(globals->get_commands()->execute(naStr_data(cmd), *node));
322 // settimer(func, dt, simtime) extension function. Falls through to
323 // FGNasalSys::setTimer(). See there for docs.
324 static naRef f_settimer(naContext c, naRef me, int argc, naRef* args)
326 nasalSys->setTimer(c, argc, args);
330 // setlistener(func, property, bool) extension function. Falls through to
331 // FGNasalSys::setListener(). See there for docs.
332 static naRef f_setlistener(naContext c, naRef me, int argc, naRef* args)
334 return nasalSys->setListener(c, argc, args);
337 // removelistener(int) extension function. Falls through to
338 // FGNasalSys::removeListener(). See there for docs.
339 static naRef f_removelistener(naContext c, naRef me, int argc, naRef* args)
341 return nasalSys->removeListener(c, argc, args);
344 // Returns a ghost handle to the argument to the currently executing
346 static naRef f_cmdarg(naContext c, naRef me, int argc, naRef* args)
348 return nasalSys->cmdArgGhost();
351 // Sets up a property interpolation. The first argument is either a
352 // ghost (SGPropertyNode_ptr*) or a string (global property path) to
353 // interpolate. The second argument is a vector of pairs of
354 // value/delta numbers.
355 static naRef f_interpolate(naContext c, naRef me, int argc, naRef* args)
357 SGPropertyNode* node;
358 naRef prop = argc > 0 ? args[0] : naNil();
359 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
360 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
363 naRef curve = argc > 1 ? args[1] : naNil();
364 if(!naIsVector(curve)) return naNil();
365 int nPoints = naVec_size(curve) / 2;
366 double* values = new double[nPoints];
367 double* deltas = new double[nPoints];
368 for(int i=0; i<nPoints; i++) {
369 values[i] = naNumValue(naVec_get(curve, 2*i)).num;
370 deltas[i] = naNumValue(naVec_get(curve, 2*i+1)).num;
373 ((SGInterpolator*)globals->get_subsystem_mgr()
374 ->get_group(SGSubsystemMgr::INIT)->get_subsystem("interpolator"))
375 ->interpolate(node, nPoints, values, deltas);
382 // This is a better RNG than the one in the default Nasal distribution
383 // (which is based on the C library rand() implementation). It will
385 static naRef f_rand(naContext c, naRef me, int argc, naRef* args)
387 return naNum(sg_random());
390 static naRef f_srand(naContext c, naRef me, int argc, naRef* args)
396 static naRef f_abort(naContext c, naRef me, int argc, naRef* args)
402 // Return an array listing of all files in a directory
403 static naRef f_directory(naContext c, naRef me, int argc, naRef* args)
405 if(argc != 1 || !naIsString(args[0]))
406 naRuntimeError(c, "bad arguments to directory()");
408 simgear::Dir d(SGPath(naStr_data(args[0])));
409 if(!d.exists()) return naNil();
410 naRef result = naNewVector(c);
412 simgear::PathList paths = d.children(simgear::Dir::TYPE_FILE | simgear::Dir::TYPE_DIR);
413 for (unsigned int i=0; i<paths.size(); ++i) {
414 std::string p = paths[i].file();
415 naVec_append(result, naStr_fromdata(naNewString(c), p.c_str(), p.size()));
422 * Given a data path, resolve it in FG_ROOT or an FG_AIRCRFT directory
424 static naRef f_resolveDataPath(naContext c, naRef me, int argc, naRef* args)
426 if(argc != 1 || !naIsString(args[0]))
427 naRuntimeError(c, "bad arguments to resolveDataPath()");
429 SGPath p = globals->resolve_maybe_aircraft_path(naStr_data(args[0]));
430 const char* pdata = p.c_str();
431 return naStr_fromdata(naNewString(c), const_cast<char*>(pdata), strlen(pdata));
435 // parsexml(<path> [, <start-tag> [, <end-tag> [, <data> [, <pi>]]]]);
437 // <path> ... absolute path to an XML file
438 // <start-tag> ... callback function with two args: tag name, attribute hash
439 // <end-tag> ... callback function with one arg: tag name
440 // <data> ... callback function with one arg: data
441 // <pi> ... callback function with two args: target, data
442 // (pi = "processing instruction")
443 // All four callback functions are optional and default to nil.
444 // The function returns nil on error, or the validated file name otherwise.
445 static naRef f_parsexml(naContext c, naRef me, int argc, naRef* args)
447 if(argc < 1 || !naIsString(args[0]))
448 naRuntimeError(c, "parsexml(): path argument missing or not a string");
449 if(argc > 5) argc = 5;
450 for(int i=1; i<argc; i++)
451 if(!(naIsNil(args[i]) || naIsFunc(args[i])))
452 naRuntimeError(c, "parsexml(): callback argument not a function");
454 const char* file = fgValidatePath(naStr_data(args[0]), false);
456 naRuntimeError(c, "parsexml(): reading '%s' denied "
457 "(unauthorized access)", naStr_data(args[0]));
460 std::ifstream input(file);
461 NasalXMLVisitor visitor(c, argc, args);
463 readXML(input, visitor);
464 } catch (const sg_exception& e) {
465 naRuntimeError(c, "parsexml(): file '%s' %s",
466 file, e.getFormattedMessage().c_str());
469 return naStr_fromdata(naNewString(c), const_cast<char*>(file), strlen(file));
472 // Return UNIX epoch time in seconds.
473 static naRef f_systime(naContext c, naRef me, int argc, naRef* args)
477 GetSystemTimeAsFileTime(&ft);
478 double t = (4294967296.0 * ft.dwHighDateTime + ft.dwLowDateTime);
479 // Converts from 100ns units in 1601 epoch to unix epoch in sec
480 return naNum((t * 1e-7) - 11644473600.0);
483 gettimeofday(&td, 0);
484 return naNum(td.tv_sec + 1e-6 * td.tv_usec);
488 // Table of extension functions. Terminate with zeros.
489 static struct { const char* name; naCFunction func; } funcs[] = {
490 { "getprop", f_getprop },
491 { "setprop", f_setprop },
492 { "print", f_print },
493 { "_fgcommand", f_fgcommand },
494 { "settimer", f_settimer },
495 { "_setlistener", f_setlistener },
496 { "removelistener", f_removelistener },
497 { "_cmdarg", f_cmdarg },
498 { "_interpolate", f_interpolate },
500 { "srand", f_srand },
501 { "abort", f_abort },
502 { "directory", f_directory },
503 { "resolvepath", f_resolveDataPath },
504 { "parsexml", f_parsexml },
505 { "systime", f_systime },
509 naRef FGNasalSys::cmdArgGhost()
511 return propNodeGhost(_cmdArg);
514 void FGNasalSys::init()
518 _context = naNewContext();
520 // Start with globals. Add it to itself as a recursive
521 // sub-reference under the name "globals". This gives client-code
522 // write access to the namespace if someone wants to do something
524 _globals = naInit_std(_context);
525 naSave(_context, _globals);
526 hashset(_globals, "globals", _globals);
528 hashset(_globals, "math", naInit_math(_context));
529 hashset(_globals, "bits", naInit_bits(_context));
530 hashset(_globals, "io", naInit_io(_context));
531 hashset(_globals, "thread", naInit_thread(_context));
532 hashset(_globals, "utf8", naInit_utf8(_context));
534 // Add our custom extension functions:
535 for(i=0; funcs[i].name; i++)
536 hashset(_globals, funcs[i].name,
537 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
541 // And our SGPropertyNode wrapper
542 hashset(_globals, "props", genPropsModule());
544 // Make a "__gcsave" hash to hold the naRef objects which get
545 // passed to handles outside the interpreter (to protect them from
546 // begin garbage-collected).
547 _gcHash = naNewHash(_context);
548 hashset(_globals, "__gcsave", _gcHash);
550 initNasalPositioned(_globals, _context, _gcHash);
552 // Now load the various source files in the Nasal directory
553 simgear::Dir nasalDir(SGPath(globals->get_fg_root(), "Nasal"));
554 loadScriptDirectory(nasalDir);
556 // Add modules in Nasal subdirectories to property tree
557 simgear::PathList directories = nasalDir.children(simgear::Dir::TYPE_DIR+
558 simgear::Dir::NO_DOT_OR_DOTDOT, "");
559 for (unsigned int i=0; i<directories.size(); ++i) {
560 simgear::Dir dir(directories[i]);
561 simgear::PathList scripts = dir.children(simgear::Dir::TYPE_FILE, ".nas");
562 addModule(directories[i].file(), scripts);
565 // set signal and remove node to avoid restoring at reinit
566 const char *s = "nasal-dir-initialized";
567 SGPropertyNode *signal = fgGetNode("/sim/signals", true);
568 signal->setBoolValue(s, true);
569 signal->removeChildren(s, false);
571 // Pull scripts out of the property tree, too
572 loadPropertyScripts();
574 // now Nasal modules are loaded, we can do some delayed work
575 postinitNasalPositioned(_globals, _context);
578 void FGNasalSys::update(double)
580 if(!_dead_listener.empty()) {
581 vector<FGNasalListener *>::iterator it, end = _dead_listener.end();
582 for(it = _dead_listener.begin(); it != end; ++it) delete *it;
583 _dead_listener.clear();
586 if (!_loadList.empty())
588 // process Nasal load hook (only one per update loop to avoid excessive lags)
589 _loadList.pop()->load();
592 if (!_unloadList.empty())
594 // process pending Nasal unload hooks after _all_ load hooks were processed
595 // (only unload one per update loop to avoid excessive lags)
596 _unloadList.pop()->unload();
599 // The global context is a legacy thing. We use dynamically
600 // created contexts for naCall() now, so that we can call them
601 // recursively. But there are still spots that want to use it for
602 // naNew*() calls, which end up leaking memory because the context
603 // only clears out its temporary vector when it's *used*. So just
604 // junk it and fetch a new/reinitialized one every frame. This is
605 // clumsy: the right solution would use the dynamic context in all
606 // cases and eliminate _context entirely. But that's more work,
607 // and this works fine (yes, they say "New" and "Free", but
608 // they're very fast, just trust me). -Andy
609 naFreeContext(_context);
610 _context = naNewContext();
613 bool pathSortPredicate(const SGPath& p1, const SGPath& p2)
615 return p1.file() < p2.file();
618 // Loads all scripts in given directory
619 void FGNasalSys::loadScriptDirectory(simgear::Dir nasalDir)
621 simgear::PathList scripts = nasalDir.children(simgear::Dir::TYPE_FILE, ".nas");
622 // sort scripts, avoid loading sequence effects due to file system's
623 // random directory order
624 std::sort(scripts.begin(), scripts.end(), pathSortPredicate);
626 for (unsigned int i=0; i<scripts.size(); ++i) {
627 SGPath fullpath(scripts[i]);
628 SGPath file = fullpath.file();
629 loadModule(fullpath, file.base().c_str());
633 // Create module with list of scripts
634 void FGNasalSys::addModule(string moduleName, simgear::PathList scripts)
636 if (scripts.size()>0)
638 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
639 SGPropertyNode* module_node = nasal->getChild(moduleName,0,true);
640 for (unsigned int i=0; i<scripts.size(); ++i) {
641 SGPropertyNode* pFileNode = module_node->getChild("file",i,true);
642 pFileNode->setStringValue(scripts[i].c_str());
644 if (!module_node->hasChild("enabled",0))
646 SGPropertyNode* node = module_node->getChild("enabled",0,true);
647 node->setBoolValue(true);
648 node->setAttribute(SGPropertyNode::USERARCHIVE,true);
653 // Loads the scripts found under /nasal in the global tree
654 void FGNasalSys::loadPropertyScripts()
656 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
659 for(int i=0; i<nasal->nChildren(); i++)
661 SGPropertyNode* n = nasal->getChild(i);
662 loadPropertyScripts(n);
666 // Loads the scripts found under /nasal in the global tree
667 void FGNasalSys::loadPropertyScripts(SGPropertyNode* n)
669 bool is_loaded = false;
671 const char* module = n->getName();
672 if(n->hasChild("module"))
673 module = n->getStringValue("module");
674 if (n->getBoolValue("enabled",true))
676 // allow multiple files to be specified within a single
680 bool file_specified = false;
682 while((fn = n->getChild("file", j)) != NULL) {
683 file_specified = true;
684 const char* file = fn->getStringValue();
686 if (!p.isAbsolute() || !p.exists())
688 p = globals->resolve_maybe_aircraft_path(file);
691 SG_LOG(SG_NASAL, SG_ALERT, "Cannot find Nasal script '" <<
692 file << "' for module '" << module << "'.");
695 ok &= p.isNull() ? false : loadModule(p, module);
699 const char* src = n->getStringValue("script");
700 if(!n->hasChild("script")) src = 0; // Hrm...
702 createModule(module, n->getPath().c_str(), src, strlen(src));
704 if(!file_specified && !src)
706 // module no longer exists - clear the archived "enable" flag
707 n->setAttribute(SGPropertyNode::USERARCHIVE,false);
708 SGPropertyNode* node = n->getChild("enabled",0,false);
710 node->setAttribute(SGPropertyNode::USERARCHIVE,false);
712 SG_LOG(SG_NASAL, SG_ALERT, "Nasal error: " <<
713 "no <file> or <script> defined in " <<
714 "/nasal/" << module);
721 SGPropertyNode* enable = n->getChild("enabled");
724 FGNasalModuleListener* listener = new FGNasalModuleListener(n);
725 enable->addChangeListener(listener, false);
728 SGPropertyNode* loaded = n->getChild("loaded",0,true);
729 loaded->setAttribute(SGPropertyNode::PRESERVE,true);
730 loaded->setBoolValue(is_loaded);
733 // Logs a runtime error, with stack trace, to the FlightGear log stream
734 void FGNasalSys::logError(naContext context)
736 SG_LOG(SG_NASAL, SG_ALERT,
737 "Nasal runtime error: " << naGetError(context));
738 SG_LOG(SG_NASAL, SG_ALERT,
739 " at " << naStr_data(naGetSourceFile(context, 0)) <<
740 ", line " << naGetLine(context, 0));
741 for(int i=1; i<naStackDepth(context); i++)
742 SG_LOG(SG_NASAL, SG_ALERT,
743 " called from: " << naStr_data(naGetSourceFile(context, i)) <<
744 ", line " << naGetLine(context, i));
747 // Reads a script file, executes it, and places the resulting
748 // namespace into the global namespace under the specified module
750 bool FGNasalSys::loadModule(SGPath file, const char* module)
753 char* buf = readfile(file.c_str(), &len);
755 SG_LOG(SG_NASAL, SG_ALERT,
756 "Nasal error: could not read script file " << file.c_str()
757 << " into module " << module);
761 bool ok = createModule(module, file.c_str(), buf, len);
766 // Parse and run. Save the local variables namespace, as it will
767 // become a sub-object of globals. The optional "arg" argument can be
768 // used to pass an associated property node to the module, which can then
769 // be accessed via cmdarg(). (This is, for example, used by XML dialogs.)
770 bool FGNasalSys::createModule(const char* moduleName, const char* fileName,
771 const char* src, int len,
772 const SGPropertyNode* cmdarg,
773 int argc, naRef* args)
775 naRef code = parse(fileName, src, len);
779 // See if we already have a module hash to use. This allows the
780 // user to, for example, add functions to the built-in math
781 // module. Make a new one if necessary.
783 naRef modname = naNewString(_context);
784 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
785 if(!naHash_get(_globals, modname, &locals))
786 locals = naNewHash(_context);
788 _cmdArg = (SGPropertyNode*)cmdarg;
790 call(code, argc, args, locals);
791 hashset(_globals, moduleName, locals);
795 void FGNasalSys::deleteModule(const char* moduleName)
797 naRef modname = naNewString(_context);
798 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
799 naHash_delete(_globals, modname);
802 naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
805 naRef srcfile = naNewString(_context);
806 naStr_fromdata(srcfile, (char*)filename, strlen(filename));
807 naRef code = naParseCode(_context, srcfile, 1, (char*)buf, len, &errLine);
809 SG_LOG(SG_NASAL, SG_ALERT,
810 "Nasal parse error: " << naGetError(_context) <<
811 " in "<< filename <<", line " << errLine);
815 // Bind to the global namespace before returning
816 return naBindFunction(_context, code, _globals);
819 bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
821 const char* nasal = arg->getStringValue("script");
822 const char* moduleName = arg->getStringValue("module");
823 naRef code = parse(arg->getPath(true).c_str(), nasal, strlen(nasal));
824 if(naIsNil(code)) return false;
826 // Commands can be run "in" a module. Make sure that module
827 // exists, and set it up as the local variables hash for the
829 naRef locals = naNil();
831 naRef modname = naNewString(_context);
832 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
833 if(!naHash_get(_globals, modname, &locals)) {
834 locals = naNewHash(_context);
835 naHash_set(_globals, modname, locals);
839 // Cache this command's argument for inspection via cmdarg(). For
840 // performance reasons, we won't bother with it if the invoked
841 // code doesn't need it.
842 _cmdArg = (SGPropertyNode*)arg;
844 call(code, 0, 0, locals);
848 // settimer(func, dt, simtime) extension function. The first argument
849 // is a Nasal function to call, the second is a delta time (from now),
850 // in seconds. The third, if present, is a boolean value indicating
851 // that "real world" time (rather than simulator time) is to be used.
853 // Implementation note: the FGTimer objects don't live inside the
854 // garbage collector, so the Nasal handler functions have to be
855 // "saved" somehow lest they be inadvertently cleaned. In this case,
856 // they are inserted into a globals.__gcsave hash and removed on
858 void FGNasalSys::setTimer(naContext c, int argc, naRef* args)
860 // Extract the handler, delta, and simtime arguments:
861 naRef handler = argc > 0 ? args[0] : naNil();
862 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler))) {
863 naRuntimeError(c, "settimer() with invalid function argument");
867 naRef delta = argc > 1 ? args[1] : naNil();
869 naRuntimeError(c, "settimer() with invalid time argument");
873 bool simtime = (argc > 2 && naTrue(args[2])) ? false : true;
875 // Generate and register a C++ timer handler
876 NasalTimer* t = new NasalTimer;
877 t->handler = handler;
878 t->gcKey = gcSave(handler);
881 globals->get_event_mgr()->addEvent("NasalTimer",
882 t, &NasalTimer::timerExpired,
886 void FGNasalSys::handleTimer(NasalTimer* t)
888 call(t->handler, 0, 0, naNil());
892 int FGNasalSys::gcSave(naRef r)
894 int key = _nextGCKey++;
895 naHash_set(_gcHash, naNum(key), r);
899 void FGNasalSys::gcRelease(int key)
901 naHash_delete(_gcHash, naNum(key));
904 void FGNasalSys::NasalTimer::timerExpired()
906 nasal->handleTimer(this);
910 int FGNasalSys::_listenerId = 0;
912 // setlistener(<property>, <func> [, <initial=0> [, <persistent=1>]])
913 // Attaches a callback function to a property (specified as a global
914 // property path string or a SGPropertyNode_ptr* ghost). If the third,
915 // optional argument (default=0) is set to 1, then the function is also
916 // called initially. If the fourth, optional argument is set to 0, then the
917 // function is only called when the property node value actually changes.
918 // Otherwise it's called independent of the value whenever the node is
919 // written to (default). The setlistener() function returns a unique
920 // id number, which is to be used as argument to the removelistener()
922 naRef FGNasalSys::setListener(naContext c, int argc, naRef* args)
924 SGPropertyNode_ptr node;
925 naRef prop = argc > 0 ? args[0] : naNil();
926 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
927 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
929 naRuntimeError(c, "setlistener() with invalid property argument");
934 SG_LOG(SG_NASAL, SG_DEBUG, "Attaching listener to tied property " <<
937 naRef code = argc > 1 ? args[1] : naNil();
938 if(!(naIsCode(code) || naIsCCode(code) || naIsFunc(code))) {
939 naRuntimeError(c, "setlistener() with invalid function argument");
943 int init = argc > 2 && naIsNum(args[2]) ? int(args[2].num) : 0;
944 int type = argc > 3 && naIsNum(args[3]) ? int(args[3].num) : 1;
945 FGNasalListener *nl = new FGNasalListener(node, code, this,
946 gcSave(code), _listenerId, init, type);
948 node->addChangeListener(nl, init != 0);
950 _listener[_listenerId] = nl;
951 return naNum(_listenerId++);
954 // removelistener(int) extension function. The argument is the id of
955 // a listener as returned by the setlistener() function.
956 naRef FGNasalSys::removeListener(naContext c, int argc, naRef* args)
958 naRef id = argc > 0 ? args[0] : naNil();
959 map<int, FGNasalListener *>::iterator it = _listener.find(int(id.num));
961 if(!naIsNum(id) || it == _listener.end() || it->second->_dead) {
962 naRuntimeError(c, "removelistener() with invalid listener id");
966 it->second->_dead = true;
967 _dead_listener.push_back(it->second);
969 return naNum(_listener.size());
974 // FGNasalListener class.
976 FGNasalListener::FGNasalListener(SGPropertyNode *node, naRef code,
977 FGNasalSys* nasal, int key, int id,
978 int init, int type) :
991 if(_type == 0 && !_init)
995 FGNasalListener::~FGNasalListener()
997 _node->removeChangeListener(this);
998 _nas->gcRelease(_gcKey);
1001 void FGNasalListener::call(SGPropertyNode* which, naRef mode)
1003 if(_active || _dead) return;
1004 SG_LOG(SG_NASAL, SG_DEBUG, "trigger listener #" << _id);
1007 arg[0] = _nas->propNodeGhost(which);
1008 arg[1] = _nas->propNodeGhost(_node);
1009 arg[2] = mode; // value changed, child added/removed
1010 arg[3] = naNum(_node != which); // child event?
1011 _nas->call(_code, 4, arg, naNil());
1015 void FGNasalListener::valueChanged(SGPropertyNode* node)
1017 if(_type < 2 && node != _node) return; // skip child events
1018 if(_type > 0 || changed(_node) || _init)
1019 call(node, naNum(0));
1024 void FGNasalListener::childAdded(SGPropertyNode*, SGPropertyNode* child)
1026 if(_type == 2) call(child, naNum(1));
1029 void FGNasalListener::childRemoved(SGPropertyNode*, SGPropertyNode* child)
1031 if(_type == 2) call(child, naNum(-1));
1034 bool FGNasalListener::changed(SGPropertyNode* node)
1036 using namespace simgear;
1037 props::Type type = node->getType();
1038 if(type == props::NONE) return false;
1039 if(type == props::UNSPECIFIED) return true;
1047 long l = node->getLongValue();
1048 result = l != _last_int;
1055 double d = node->getDoubleValue();
1056 result = d != _last_float;
1062 string s = node->getStringValue();
1063 result = s != _last_string;
1072 // FGNasalModelData class. If sgLoad3DModel() is called with a pointer to
1073 // such a class, then it lets modelLoaded() run the <load> script, and the
1074 // destructor the <unload> script. The latter happens when the model branch
1075 // is removed from the scene graph.
1077 unsigned int FGNasalModelData::_module_id = 0;
1079 void FGNasalModelData::load()
1081 std::stringstream m;
1082 m << "__model" << _module_id++;
1085 SG_LOG(SG_NASAL, SG_DEBUG, "Loading nasal module " << _module.c_str());
1087 const char *s = _load ? _load->getStringValue() : "";
1090 arg[0] = nasalSys->propNodeGhost(_root);
1091 arg[1] = nasalSys->propNodeGhost(_prop);
1092 nasalSys->createModule(_module.c_str(), _path.c_str(), s, strlen(s),
1096 void FGNasalModelData::unload()
1098 if (_module.empty())
1102 SG_LOG(SG_NASAL, SG_WARN, "Trying to run an <unload> script "
1103 "without Nasal subsystem present.");
1107 SG_LOG(SG_NASAL, SG_DEBUG, "Unloading nasal module " << _module.c_str());
1111 const char *s = _unload->getStringValue();
1112 nasalSys->createModule(_module.c_str(), _module.c_str(), s, strlen(s), _root);
1115 nasalSys->deleteModule(_module.c_str());
1118 void FGNasalModelDataProxy::modelLoaded(const string& path, SGPropertyNode *prop,
1122 SG_LOG(SG_NASAL, SG_WARN, "Trying to run a <load> script "
1123 "without Nasal subsystem present.");
1130 SGPropertyNode *nasal = prop->getNode("nasal");
1134 SGPropertyNode* load = nasal->getNode("load");
1135 SGPropertyNode* unload = nasal->getNode("unload");
1137 if ((!load) && (!unload))
1140 _data = new FGNasalModelData(_root, path, prop, load, unload);
1142 // register Nasal module to be created and loaded in the main thread.
1143 nasalSys->registerToLoad(_data);
1146 FGNasalModelDataProxy::~FGNasalModelDataProxy()
1148 // when necessary, register Nasal module to be destroyed/unloaded
1149 // in the main thread.
1150 if ((_data.valid())&&(nasalSys))
1151 nasalSys->registerToUnload(_data);
1154 // NasalXMLVisitor class: handles EasyXML visitor callback for parsexml()
1156 NasalXMLVisitor::NasalXMLVisitor(naContext c, int argc, naRef* args) :
1157 _c(naSubContext(c)),
1158 _start_element(argc > 1 ? args[1] : naNil()),
1159 _end_element(argc > 2 ? args[2] : naNil()),
1160 _data(argc > 3 ? args[3] : naNil()),
1161 _pi(argc > 4 ? args[4] : naNil())
1165 void NasalXMLVisitor::startElement(const char* tag, const XMLAttributes& a)
1167 if(naIsNil(_start_element)) return;
1168 naRef attr = naNewHash(_c);
1169 for(int i=0; i<a.size(); i++) {
1170 naRef name = make_string(a.getName(i));
1171 naRef value = make_string(a.getValue(i));
1172 naHash_set(attr, name, value);
1174 call(_start_element, 2, make_string(tag), attr);
1177 void NasalXMLVisitor::endElement(const char* tag)
1179 if(!naIsNil(_end_element)) call(_end_element, 1, make_string(tag));
1182 void NasalXMLVisitor::data(const char* str, int len)
1184 if(!naIsNil(_data)) call(_data, 1, make_string(str, len));
1187 void NasalXMLVisitor::pi(const char* target, const char* data)
1189 if(!naIsNil(_pi)) call(_pi, 2, make_string(target), make_string(data));
1192 void NasalXMLVisitor::call(naRef func, int num, naRef a, naRef b)
1197 naCall(_c, func, num, args, naNil(), naNil());
1202 naRef NasalXMLVisitor::make_string(const char* s, int n)
1204 return naStr_fromdata(naNewString(_c), const_cast<char *>(s),
1205 n < 0 ? strlen(s) : n);