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 // Does a naCall() in a new context. Wrapped here to make lock
103 // tracking easier. Extension functions are called with the lock, but
104 // we have to release it before making a new naCall(). So rather than
105 // drop the lock in every extension function that might call back into
106 // Nasal, we keep a stack depth counter here and only unlock/lock
107 // around the naCall if it isn't the first one.
108 naRef FGNasalSys::call(naRef code, int argc, naRef* args, naRef locals)
110 naContext ctx = naNewContext();
111 if(_callCount) naModUnlock();
113 naRef result = naCall(ctx, code, argc, args, naNil(), locals);
117 if(_callCount) naModLock();
122 FGNasalSys::~FGNasalSys()
125 map<int, FGNasalListener *>::iterator it, end = _listener.end();
126 for(it = _listener.begin(); it != end; ++it)
129 naFreeContext(_context);
133 bool FGNasalSys::parseAndRun(const char* sourceCode)
135 naRef code = parse("FGNasalSys::parseAndRun()", sourceCode,
139 call(code, 0, 0, naNil());
143 FGNasalScript* FGNasalSys::parseScript(const char* src, const char* name)
145 FGNasalScript* script = new FGNasalScript();
146 script->_gcKey = -1; // important, if we delete it on a parse
147 script->_nas = this; // error, don't clobber a real handle!
151 sprintf(buf, "FGNasalScript@%p", (void *)script);
155 script->_code = parse(name, src, strlen(src));
156 if(naIsNil(script->_code)) {
161 script->_gcKey = gcSave(script->_code);
165 // Utility. Sets a named key in a hash by C string, rather than nasal
167 void FGNasalSys::hashset(naRef hash, const char* key, naRef val)
169 naRef s = naNewString(_context);
170 naStr_fromdata(s, (char*)key, strlen(key));
171 naHash_set(hash, s, val);
174 // The get/setprop functions accept a *list* of strings and walk
175 // through the property tree with them to find the appropriate node.
176 // This allows a Nasal object to hold onto a property path and use it
177 // like a node object, e.g. setprop(ObjRoot, "size-parsecs", 2.02). This
178 // is the utility function that walks the property tree.
179 // Future enhancement: support integer arguments to specify array
181 static SGPropertyNode* findnode(naContext c, naRef* vec, int len)
183 SGPropertyNode* p = globals->get_props();
185 for(int i=0; i<len; i++) {
187 if(!naIsString(a)) return 0;
188 p = p->getNode(naStr_data(a));
191 } catch (const string& err) {
192 naRuntimeError(c, (char *)err.c_str());
198 // getprop() extension function. Concatenates its string arguments as
199 // property names and returns the value of the specified property. Or
200 // nil if it doesn't exist.
201 static naRef f_getprop(naContext c, naRef me, int argc, naRef* args)
203 using namespace simgear;
204 const SGPropertyNode* p = findnode(c, args, argc);
205 if(!p) return naNil();
207 switch(p->getType()) {
208 case props::BOOL: case props::INT:
209 case props::LONG: case props::FLOAT:
212 double dv = p->getDoubleValue();
213 if (osg::isNaN(dv)) {
214 SG_LOG(SG_NASAL, SG_ALERT, "Nasal getprop: property " << p->getPath() << " is NaN");
222 case props::UNSPECIFIED:
224 naRef nastr = naNewString(c);
225 const char* val = p->getStringValue();
226 naStr_fromdata(nastr, (char*)val, strlen(val));
229 case props::ALIAS: // <--- FIXME, recurse?
235 // setprop() extension function. Concatenates its string arguments as
236 // property names and sets the value of the specified property to the
238 static naRef f_setprop(naContext c, naRef me, int argc, naRef* args)
241 char buf[BUFLEN + 1];
245 if(argc < 2) naRuntimeError(c, "setprop() expects at least 2 arguments");
246 for(int i=0; i<argc-1; i++) {
247 naRef s = naStringValue(c, args[i]);
248 if(naIsNil(s)) return naNil();
249 strncpy(p, naStr_data(s), buflen);
251 buflen = BUFLEN - (p - buf);
252 if(i < (argc-2) && buflen > 0) {
258 SGPropertyNode* props = globals->get_props();
259 naRef val = args[argc-1];
262 if(naIsString(val)) result = props->setStringValue(buf, naStr_data(val));
264 naRef n = naNumValue(val);
266 naRuntimeError(c, "setprop() value is not string or number");
268 if (osg::isNaN(n.num)) {
269 naRuntimeError(c, "setprop() passed a NaN");
272 result = props->setDoubleValue(buf, n.num);
274 } catch (const string& err) {
275 naRuntimeError(c, (char *)err.c_str());
277 return naNum(result);
281 // print() extension function. Concatenates and prints its arguments
282 // to the FlightGear log. Uses the highest log level (SG_ALERT), to
283 // make sure it appears. Is there better way to do this?
284 static naRef f_print(naContext c, naRef me, int argc, naRef* args)
288 for(int i=0; i<n; i++) {
289 naRef s = naStringValue(c, args[i]);
290 if(naIsNil(s)) continue;
291 buf += naStr_data(s);
293 SG_LOG(SG_NASAL, SG_ALERT, buf);
294 return naNum(buf.length());
297 // fgcommand() extension function. Executes a named command via the
298 // FlightGear command manager. Takes a single property node name as
300 static naRef f_fgcommand(naContext c, naRef me, int argc, naRef* args)
302 naRef cmd = argc > 0 ? args[0] : naNil();
303 naRef props = argc > 1 ? args[1] : naNil();
304 if(!naIsString(cmd) || (!naIsNil(props) && !naIsGhost(props)))
305 naRuntimeError(c, "bad arguments to fgcommand()");
306 SGPropertyNode_ptr tmp, *node;
308 node = (SGPropertyNode_ptr*)naGhost_ptr(props);
310 tmp = new SGPropertyNode();
313 return naNum(globals->get_commands()->execute(naStr_data(cmd), *node));
316 // settimer(func, dt, simtime) extension function. Falls through to
317 // FGNasalSys::setTimer(). See there for docs.
318 static naRef f_settimer(naContext c, naRef me, int argc, naRef* args)
320 nasalSys->setTimer(c, argc, args);
324 // setlistener(func, property, bool) extension function. Falls through to
325 // FGNasalSys::setListener(). See there for docs.
326 static naRef f_setlistener(naContext c, naRef me, int argc, naRef* args)
328 return nasalSys->setListener(c, argc, args);
331 // removelistener(int) extension function. Falls through to
332 // FGNasalSys::removeListener(). See there for docs.
333 static naRef f_removelistener(naContext c, naRef me, int argc, naRef* args)
335 return nasalSys->removeListener(c, argc, args);
338 // Returns a ghost handle to the argument to the currently executing
340 static naRef f_cmdarg(naContext c, naRef me, int argc, naRef* args)
342 return nasalSys->cmdArgGhost();
345 // Sets up a property interpolation. The first argument is either a
346 // ghost (SGPropertyNode_ptr*) or a string (global property path) to
347 // interpolate. The second argument is a vector of pairs of
348 // value/delta numbers.
349 static naRef f_interpolate(naContext c, naRef me, int argc, naRef* args)
351 SGPropertyNode* node;
352 naRef prop = argc > 0 ? args[0] : naNil();
353 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
354 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
357 naRef curve = argc > 1 ? args[1] : naNil();
358 if(!naIsVector(curve)) return naNil();
359 int nPoints = naVec_size(curve) / 2;
360 double* values = new double[nPoints];
361 double* deltas = new double[nPoints];
362 for(int i=0; i<nPoints; i++) {
363 values[i] = naNumValue(naVec_get(curve, 2*i)).num;
364 deltas[i] = naNumValue(naVec_get(curve, 2*i+1)).num;
367 ((SGInterpolator*)globals->get_subsystem_mgr()
368 ->get_group(SGSubsystemMgr::INIT)->get_subsystem("interpolator"))
369 ->interpolate(node, nPoints, values, deltas);
376 // This is a better RNG than the one in the default Nasal distribution
377 // (which is based on the C library rand() implementation). It will
379 static naRef f_rand(naContext c, naRef me, int argc, naRef* args)
381 return naNum(sg_random());
384 static naRef f_srand(naContext c, naRef me, int argc, naRef* args)
390 static naRef f_abort(naContext c, naRef me, int argc, naRef* args)
396 // Return an array listing of all files in a directory
397 static naRef f_directory(naContext c, naRef me, int argc, naRef* args)
399 if(argc != 1 || !naIsString(args[0]))
400 naRuntimeError(c, "bad arguments to directory()");
402 simgear::Dir d(SGPath(naStr_data(args[0])));
403 if(!d.exists()) return naNil();
404 naRef result = naNewVector(c);
406 simgear::PathList paths = d.children(simgear::Dir::TYPE_FILE | simgear::Dir::TYPE_DIR);
407 for (unsigned int i=0; i<paths.size(); ++i) {
408 std::string p = paths[i].file();
409 naVec_append(result, naStr_fromdata(naNewString(c), p.c_str(), p.size()));
416 * Given a data path, resolve it in FG_ROOT or an FG_AIRCRFT directory
418 static naRef f_resolveDataPath(naContext c, naRef me, int argc, naRef* args)
420 if(argc != 1 || !naIsString(args[0]))
421 naRuntimeError(c, "bad arguments to resolveDataPath()");
423 SGPath p = globals->resolve_maybe_aircraft_path(naStr_data(args[0]));
424 const char* pdata = p.c_str();
425 return naStr_fromdata(naNewString(c), const_cast<char*>(pdata), strlen(pdata));
429 // parsexml(<path> [, <start-tag> [, <end-tag> [, <data> [, <pi>]]]]);
431 // <path> ... absolute path to an XML file
432 // <start-tag> ... callback function with two args: tag name, attribute hash
433 // <end-tag> ... callback function with one arg: tag name
434 // <data> ... callback function with one arg: data
435 // <pi> ... callback function with two args: target, data
436 // (pi = "processing instruction")
437 // All four callback functions are optional and default to nil.
438 // The function returns nil on error, or the validated file name otherwise.
439 static naRef f_parsexml(naContext c, naRef me, int argc, naRef* args)
441 if(argc < 1 || !naIsString(args[0]))
442 naRuntimeError(c, "parsexml(): path argument missing or not a string");
443 if(argc > 5) argc = 5;
444 for(int i=1; i<argc; i++)
445 if(!(naIsNil(args[i]) || naIsFunc(args[i])))
446 naRuntimeError(c, "parsexml(): callback argument not a function");
448 const char* file = fgValidatePath(naStr_data(args[0]), false);
450 naRuntimeError(c, "parsexml(): reading '%s' denied "
451 "(unauthorized access)", naStr_data(args[0]));
454 std::ifstream input(file);
455 NasalXMLVisitor visitor(c, argc, args);
457 readXML(input, visitor);
458 } catch (const sg_exception& e) {
459 naRuntimeError(c, "parsexml(): file '%s' %s",
460 file, e.getFormattedMessage().c_str());
463 return naStr_fromdata(naNewString(c), const_cast<char*>(file), strlen(file));
466 // Return UNIX epoch time in seconds.
467 static naRef f_systime(naContext c, naRef me, int argc, naRef* args)
471 GetSystemTimeAsFileTime(&ft);
472 double t = (4294967296.0 * ft.dwHighDateTime + ft.dwLowDateTime);
473 // Converts from 100ns units in 1601 epoch to unix epoch in sec
474 return naNum((t * 1e-7) - 11644473600.0);
477 gettimeofday(&td, 0);
478 return naNum(td.tv_sec + 1e-6 * td.tv_usec);
482 // Table of extension functions. Terminate with zeros.
483 static struct { const char* name; naCFunction func; } funcs[] = {
484 { "getprop", f_getprop },
485 { "setprop", f_setprop },
486 { "print", f_print },
487 { "_fgcommand", f_fgcommand },
488 { "settimer", f_settimer },
489 { "_setlistener", f_setlistener },
490 { "removelistener", f_removelistener },
491 { "_cmdarg", f_cmdarg },
492 { "_interpolate", f_interpolate },
494 { "srand", f_srand },
495 { "abort", f_abort },
496 { "directory", f_directory },
497 { "resolvepath", f_resolveDataPath },
498 { "parsexml", f_parsexml },
499 { "systime", f_systime },
503 naRef FGNasalSys::cmdArgGhost()
505 return propNodeGhost(_cmdArg);
508 void FGNasalSys::init()
512 _context = naNewContext();
514 // Start with globals. Add it to itself as a recursive
515 // sub-reference under the name "globals". This gives client-code
516 // write access to the namespace if someone wants to do something
518 _globals = naInit_std(_context);
519 naSave(_context, _globals);
520 hashset(_globals, "globals", _globals);
522 hashset(_globals, "math", naInit_math(_context));
523 hashset(_globals, "bits", naInit_bits(_context));
524 hashset(_globals, "io", naInit_io(_context));
525 hashset(_globals, "thread", naInit_thread(_context));
526 hashset(_globals, "utf8", naInit_utf8(_context));
528 // Add our custom extension functions:
529 for(i=0; funcs[i].name; i++)
530 hashset(_globals, funcs[i].name,
531 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
535 // And our SGPropertyNode wrapper
536 hashset(_globals, "props", genPropsModule());
538 // Make a "__gcsave" hash to hold the naRef objects which get
539 // passed to handles outside the interpreter (to protect them from
540 // begin garbage-collected).
541 _gcHash = naNewHash(_context);
542 hashset(_globals, "__gcsave", _gcHash);
544 initNasalPositioned(_globals, _context, _gcHash);
546 // Now load the various source files in the Nasal directory
547 simgear::Dir nasalDir(SGPath(globals->get_fg_root(), "Nasal"));
548 loadScriptDirectory(nasalDir);
550 // Add modules in Nasal subdirectories to property tree
551 simgear::PathList directories = nasalDir.children(simgear::Dir::TYPE_DIR+
552 simgear::Dir::NO_DOT_OR_DOTDOT, "");
553 for (unsigned int i=0; i<directories.size(); ++i) {
554 simgear::Dir dir(directories[i]);
555 simgear::PathList scripts = dir.children(simgear::Dir::TYPE_FILE, ".nas");
556 addModule(directories[i].file(), scripts);
559 // set signal and remove node to avoid restoring at reinit
560 const char *s = "nasal-dir-initialized";
561 SGPropertyNode *signal = fgGetNode("/sim/signals", true);
562 signal->setBoolValue(s, true);
563 signal->removeChildren(s, false);
565 // Pull scripts out of the property tree, too
566 loadPropertyScripts();
568 // now Nasal modules are loaded, we can do some delayed work
569 postinitNasalPositioned(_globals, _context);
572 void FGNasalSys::update(double)
574 if(!_dead_listener.empty()) {
575 vector<FGNasalListener *>::iterator it, end = _dead_listener.end();
576 for(it = _dead_listener.begin(); it != end; ++it) delete *it;
577 _dead_listener.clear();
580 if (!_loadList.empty())
582 // process Nasal load hook (only one per update loop to avoid excessive lags)
583 _loadList.pop()->load();
586 if (!_unloadList.empty())
588 // process pending Nasal unload hooks after _all_ load hooks were processed
589 // (only unload one per update loop to avoid excessive lags)
590 _unloadList.pop()->unload();
593 // The global context is a legacy thing. We use dynamically
594 // created contexts for naCall() now, so that we can call them
595 // recursively. But there are still spots that want to use it for
596 // naNew*() calls, which end up leaking memory because the context
597 // only clears out its temporary vector when it's *used*. So just
598 // junk it and fetch a new/reinitialized one every frame. This is
599 // clumsy: the right solution would use the dynamic context in all
600 // cases and eliminate _context entirely. But that's more work,
601 // and this works fine (yes, they say "New" and "Free", but
602 // they're very fast, just trust me). -Andy
603 naFreeContext(_context);
604 _context = naNewContext();
607 bool pathSortPredicate(const SGPath& p1, const SGPath& p2)
609 return p1.file() < p2.file();
612 // Loads all scripts in given directory
613 void FGNasalSys::loadScriptDirectory(simgear::Dir nasalDir)
615 simgear::PathList scripts = nasalDir.children(simgear::Dir::TYPE_FILE, ".nas");
616 // sort scripts, avoid loading sequence effects due to file system's
617 // random directory order
618 std::sort(scripts.begin(), scripts.end(), pathSortPredicate);
620 for (unsigned int i=0; i<scripts.size(); ++i) {
621 SGPath fullpath(scripts[i]);
622 SGPath file = fullpath.file();
623 loadModule(fullpath, file.base().c_str());
627 // Create module with list of scripts
628 void FGNasalSys::addModule(string moduleName, simgear::PathList scripts)
630 if (scripts.size()>0)
632 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
633 SGPropertyNode* module_node = nasal->getChild(moduleName,0,true);
634 for (unsigned int i=0; i<scripts.size(); ++i) {
635 SGPropertyNode* pFileNode = module_node->getChild("file",i,true);
636 pFileNode->setStringValue(scripts[i].c_str());
638 if (!module_node->hasChild("enabled",0))
640 SGPropertyNode* node = module_node->getChild("enabled",0,true);
641 node->setBoolValue(true);
642 node->setAttribute(SGPropertyNode::USERARCHIVE,true);
647 // Loads the scripts found under /nasal in the global tree
648 void FGNasalSys::loadPropertyScripts()
650 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
653 for(int i=0; i<nasal->nChildren(); i++)
655 SGPropertyNode* n = nasal->getChild(i);
656 loadPropertyScripts(n);
660 // Loads the scripts found under /nasal in the global tree
661 void FGNasalSys::loadPropertyScripts(SGPropertyNode* n)
663 bool is_loaded = false;
665 const char* module = n->getName();
666 if(n->hasChild("module"))
667 module = n->getStringValue("module");
668 if (n->getBoolValue("enabled",true))
670 // allow multiple files to be specified within a single
674 bool file_specified = false;
676 while((fn = n->getChild("file", j)) != NULL) {
677 file_specified = true;
678 const char* file = fn->getStringValue();
680 if (!p.isAbsolute() || !p.exists())
682 p = globals->resolve_maybe_aircraft_path(file);
685 SG_LOG(SG_NASAL, SG_ALERT, "Cannot find Nasal script '" <<
686 file << "' for module '" << module << "'.");
689 ok &= p.isNull() ? false : loadModule(p, module);
693 const char* src = n->getStringValue("script");
694 if(!n->hasChild("script")) src = 0; // Hrm...
696 createModule(module, n->getPath().c_str(), src, strlen(src));
698 if(!file_specified && !src)
700 // module no longer exists - clear the archived "enable" flag
701 n->setAttribute(SGPropertyNode::USERARCHIVE,false);
702 SGPropertyNode* node = n->getChild("enabled",0,false);
704 node->setAttribute(SGPropertyNode::USERARCHIVE,false);
706 SG_LOG(SG_NASAL, SG_ALERT, "Nasal error: " <<
707 "no <file> or <script> defined in " <<
708 "/nasal/" << module);
715 SGPropertyNode* enable = n->getChild("enabled");
718 FGNasalModuleListener* listener = new FGNasalModuleListener(n);
719 enable->addChangeListener(listener, false);
722 SGPropertyNode* loaded = n->getChild("loaded",0,true);
723 loaded->setAttribute(SGPropertyNode::PRESERVE,true);
724 loaded->setBoolValue(is_loaded);
727 // Logs a runtime error, with stack trace, to the FlightGear log stream
728 void FGNasalSys::logError(naContext context)
730 SG_LOG(SG_NASAL, SG_ALERT,
731 "Nasal runtime error: " << naGetError(context));
732 SG_LOG(SG_NASAL, SG_ALERT,
733 " at " << naStr_data(naGetSourceFile(context, 0)) <<
734 ", line " << naGetLine(context, 0));
735 for(int i=1; i<naStackDepth(context); i++)
736 SG_LOG(SG_NASAL, SG_ALERT,
737 " called from: " << naStr_data(naGetSourceFile(context, i)) <<
738 ", line " << naGetLine(context, i));
741 // Reads a script file, executes it, and places the resulting
742 // namespace into the global namespace under the specified module
744 bool FGNasalSys::loadModule(SGPath file, const char* module)
747 char* buf = readfile(file.c_str(), &len);
749 SG_LOG(SG_NASAL, SG_ALERT,
750 "Nasal error: could not read script file " << file.c_str()
751 << " into module " << module);
755 bool ok = createModule(module, file.c_str(), buf, len);
760 // Parse and run. Save the local variables namespace, as it will
761 // become a sub-object of globals. The optional "arg" argument can be
762 // used to pass an associated property node to the module, which can then
763 // be accessed via cmdarg(). (This is, for example, used by XML dialogs.)
764 bool FGNasalSys::createModule(const char* moduleName, const char* fileName,
765 const char* src, int len,
766 const SGPropertyNode* cmdarg,
767 int argc, naRef* args)
769 naRef code = parse(fileName, src, len);
773 // See if we already have a module hash to use. This allows the
774 // user to, for example, add functions to the built-in math
775 // module. Make a new one if necessary.
777 naRef modname = naNewString(_context);
778 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
779 if(!naHash_get(_globals, modname, &locals))
780 locals = naNewHash(_context);
782 _cmdArg = (SGPropertyNode*)cmdarg;
784 call(code, argc, args, locals);
785 hashset(_globals, moduleName, locals);
789 void FGNasalSys::deleteModule(const char* moduleName)
791 naRef modname = naNewString(_context);
792 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
793 naHash_delete(_globals, modname);
796 naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
799 naRef srcfile = naNewString(_context);
800 naStr_fromdata(srcfile, (char*)filename, strlen(filename));
801 naRef code = naParseCode(_context, srcfile, 1, (char*)buf, len, &errLine);
803 SG_LOG(SG_NASAL, SG_ALERT,
804 "Nasal parse error: " << naGetError(_context) <<
805 " in "<< filename <<", line " << errLine);
809 // Bind to the global namespace before returning
810 return naBindFunction(_context, code, _globals);
813 bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
815 const char* nasal = arg->getStringValue("script");
816 const char* moduleName = arg->getStringValue("module");
817 naRef code = parse(arg->getPath(true).c_str(), nasal, strlen(nasal));
818 if(naIsNil(code)) return false;
820 // Commands can be run "in" a module. Make sure that module
821 // exists, and set it up as the local variables hash for the
823 naRef locals = naNil();
825 naRef modname = naNewString(_context);
826 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
827 if(!naHash_get(_globals, modname, &locals)) {
828 locals = naNewHash(_context);
829 naHash_set(_globals, modname, locals);
833 // Cache this command's argument for inspection via cmdarg(). For
834 // performance reasons, we won't bother with it if the invoked
835 // code doesn't need it.
836 _cmdArg = (SGPropertyNode*)arg;
838 call(code, 0, 0, locals);
842 // settimer(func, dt, simtime) extension function. The first argument
843 // is a Nasal function to call, the second is a delta time (from now),
844 // in seconds. The third, if present, is a boolean value indicating
845 // that "real world" time (rather than simulator time) is to be used.
847 // Implementation note: the FGTimer objects don't live inside the
848 // garbage collector, so the Nasal handler functions have to be
849 // "saved" somehow lest they be inadvertently cleaned. In this case,
850 // they are inserted into a globals.__gcsave hash and removed on
852 void FGNasalSys::setTimer(naContext c, int argc, naRef* args)
854 // Extract the handler, delta, and simtime arguments:
855 naRef handler = argc > 0 ? args[0] : naNil();
856 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler))) {
857 naRuntimeError(c, "settimer() with invalid function argument");
861 naRef delta = argc > 1 ? args[1] : naNil();
863 naRuntimeError(c, "settimer() with invalid time argument");
867 bool simtime = (argc > 2 && naTrue(args[2])) ? false : true;
869 // Generate and register a C++ timer handler
870 NasalTimer* t = new NasalTimer;
871 t->handler = handler;
872 t->gcKey = gcSave(handler);
875 globals->get_event_mgr()->addEvent("NasalTimer",
876 t, &NasalTimer::timerExpired,
880 void FGNasalSys::handleTimer(NasalTimer* t)
882 call(t->handler, 0, 0, naNil());
886 int FGNasalSys::gcSave(naRef r)
888 int key = _nextGCKey++;
889 naHash_set(_gcHash, naNum(key), r);
893 void FGNasalSys::gcRelease(int key)
895 naHash_delete(_gcHash, naNum(key));
898 void FGNasalSys::NasalTimer::timerExpired()
900 nasal->handleTimer(this);
904 int FGNasalSys::_listenerId = 0;
906 // setlistener(<property>, <func> [, <initial=0> [, <persistent=1>]])
907 // Attaches a callback function to a property (specified as a global
908 // property path string or a SGPropertyNode_ptr* ghost). If the third,
909 // optional argument (default=0) is set to 1, then the function is also
910 // called initially. If the fourth, optional argument is set to 0, then the
911 // function is only called when the property node value actually changes.
912 // Otherwise it's called independent of the value whenever the node is
913 // written to (default). The setlistener() function returns a unique
914 // id number, which is to be used as argument to the removelistener()
916 naRef FGNasalSys::setListener(naContext c, int argc, naRef* args)
918 SGPropertyNode_ptr node;
919 naRef prop = argc > 0 ? args[0] : naNil();
920 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
921 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
923 naRuntimeError(c, "setlistener() with invalid property argument");
928 SG_LOG(SG_NASAL, SG_DEBUG, "Attaching listener to tied property " <<
931 naRef code = argc > 1 ? args[1] : naNil();
932 if(!(naIsCode(code) || naIsCCode(code) || naIsFunc(code))) {
933 naRuntimeError(c, "setlistener() with invalid function argument");
937 int init = argc > 2 && naIsNum(args[2]) ? int(args[2].num) : 0;
938 int type = argc > 3 && naIsNum(args[3]) ? int(args[3].num) : 1;
939 FGNasalListener *nl = new FGNasalListener(node, code, this,
940 gcSave(code), _listenerId, init, type);
942 node->addChangeListener(nl, init != 0);
944 _listener[_listenerId] = nl;
945 return naNum(_listenerId++);
948 // removelistener(int) extension function. The argument is the id of
949 // a listener as returned by the setlistener() function.
950 naRef FGNasalSys::removeListener(naContext c, int argc, naRef* args)
952 naRef id = argc > 0 ? args[0] : naNil();
953 map<int, FGNasalListener *>::iterator it = _listener.find(int(id.num));
955 if(!naIsNum(id) || it == _listener.end() || it->second->_dead) {
956 naRuntimeError(c, "removelistener() with invalid listener id");
960 it->second->_dead = true;
961 _dead_listener.push_back(it->second);
963 return naNum(_listener.size());
968 // FGNasalListener class.
970 FGNasalListener::FGNasalListener(SGPropertyNode *node, naRef code,
971 FGNasalSys* nasal, int key, int id,
972 int init, int type) :
985 if(_type == 0 && !_init)
989 FGNasalListener::~FGNasalListener()
991 _node->removeChangeListener(this);
992 _nas->gcRelease(_gcKey);
995 void FGNasalListener::call(SGPropertyNode* which, naRef mode)
997 if(_active || _dead) return;
998 SG_LOG(SG_NASAL, SG_DEBUG, "trigger listener #" << _id);
1001 arg[0] = _nas->propNodeGhost(which);
1002 arg[1] = _nas->propNodeGhost(_node);
1003 arg[2] = mode; // value changed, child added/removed
1004 arg[3] = naNum(_node != which); // child event?
1005 _nas->call(_code, 4, arg, naNil());
1009 void FGNasalListener::valueChanged(SGPropertyNode* node)
1011 if(_type < 2 && node != _node) return; // skip child events
1012 if(_type > 0 || changed(_node) || _init)
1013 call(node, naNum(0));
1018 void FGNasalListener::childAdded(SGPropertyNode*, SGPropertyNode* child)
1020 if(_type == 2) call(child, naNum(1));
1023 void FGNasalListener::childRemoved(SGPropertyNode*, SGPropertyNode* child)
1025 if(_type == 2) call(child, naNum(-1));
1028 bool FGNasalListener::changed(SGPropertyNode* node)
1030 using namespace simgear;
1031 props::Type type = node->getType();
1032 if(type == props::NONE) return false;
1033 if(type == props::UNSPECIFIED) return true;
1041 long l = node->getLongValue();
1042 result = l != _last_int;
1049 double d = node->getDoubleValue();
1050 result = d != _last_float;
1056 string s = node->getStringValue();
1057 result = s != _last_string;
1066 // FGNasalModelData class. If sgLoad3DModel() is called with a pointer to
1067 // such a class, then it lets modelLoaded() run the <load> script, and the
1068 // destructor the <unload> script. The latter happens when the model branch
1069 // is removed from the scene graph.
1071 unsigned int FGNasalModelData::_module_id = 0;
1073 void FGNasalModelData::load()
1075 std::stringstream m;
1076 m << "__model" << _module_id++;
1079 SG_LOG(SG_NASAL, SG_DEBUG, "Loading nasal module " << _module.c_str());
1081 const char *s = _load ? _load->getStringValue() : "";
1084 arg[0] = nasalSys->propNodeGhost(_root);
1085 arg[1] = nasalSys->propNodeGhost(_prop);
1086 nasalSys->createModule(_module.c_str(), _path.c_str(), s, strlen(s),
1090 void FGNasalModelData::unload()
1092 if (_module.empty())
1096 SG_LOG(SG_NASAL, SG_WARN, "Trying to run an <unload> script "
1097 "without Nasal subsystem present.");
1101 SG_LOG(SG_NASAL, SG_DEBUG, "Unloading nasal module " << _module.c_str());
1105 const char *s = _unload->getStringValue();
1106 nasalSys->createModule(_module.c_str(), _module.c_str(), s, strlen(s), _root);
1109 nasalSys->deleteModule(_module.c_str());
1112 void FGNasalModelDataProxy::modelLoaded(const string& path, SGPropertyNode *prop,
1116 SG_LOG(SG_NASAL, SG_WARN, "Trying to run a <load> script "
1117 "without Nasal subsystem present.");
1124 SGPropertyNode *nasal = prop->getNode("nasal");
1128 SGPropertyNode* load = nasal->getNode("load");
1129 SGPropertyNode* unload = nasal->getNode("unload");
1131 if ((!load) && (!unload))
1134 _data = new FGNasalModelData(_root, path, prop, load, unload);
1136 // register Nasal module to be created and loaded in the main thread.
1137 nasalSys->registerToLoad(_data);
1140 FGNasalModelDataProxy::~FGNasalModelDataProxy()
1142 // when necessary, register Nasal module to be destroyed/unloaded
1143 // in the main thread.
1144 if ((_data.valid())&&(nasalSys))
1145 nasalSys->registerToUnload(_data);
1148 // NasalXMLVisitor class: handles EasyXML visitor callback for parsexml()
1150 NasalXMLVisitor::NasalXMLVisitor(naContext c, int argc, naRef* args) :
1151 _c(naSubContext(c)),
1152 _start_element(argc > 1 ? args[1] : naNil()),
1153 _end_element(argc > 2 ? args[2] : naNil()),
1154 _data(argc > 3 ? args[3] : naNil()),
1155 _pi(argc > 4 ? args[4] : naNil())
1159 void NasalXMLVisitor::startElement(const char* tag, const XMLAttributes& a)
1161 if(naIsNil(_start_element)) return;
1162 naRef attr = naNewHash(_c);
1163 for(int i=0; i<a.size(); i++) {
1164 naRef name = make_string(a.getName(i));
1165 naRef value = make_string(a.getValue(i));
1166 naHash_set(attr, name, value);
1168 call(_start_element, 2, make_string(tag), attr);
1171 void NasalXMLVisitor::endElement(const char* tag)
1173 if(!naIsNil(_end_element)) call(_end_element, 1, make_string(tag));
1176 void NasalXMLVisitor::data(const char* str, int len)
1178 if(!naIsNil(_data)) call(_data, 1, make_string(str, len));
1181 void NasalXMLVisitor::pi(const char* target, const char* data)
1183 if(!naIsNil(_pi)) call(_pi, 2, make_string(target), make_string(data));
1186 void NasalXMLVisitor::call(naRef func, int num, naRef a, naRef b)
1191 naCall(_c, func, num, args, naNil(), naNil());
1196 naRef NasalXMLVisitor::make_string(const char* s, int n)
1198 return naStr_fromdata(naNewString(_c), const_cast<char *>(s),
1199 n < 0 ? strlen(s) : n);