8 #include <simgear/nasal/nasal.h>
9 #include <simgear/props/props.hxx>
10 #include <simgear/math/sg_random.h>
11 #include <simgear/misc/sg_path.hxx>
12 #include <simgear/misc/interpolator.hxx>
13 #include <simgear/structure/commands.hxx>
15 #include <Main/globals.hxx>
16 #include <Main/fg_props.hxx>
18 #include "NasalSys.hxx"
19 #include "NasalDisplay.hxx"
21 // Read and return file contents in a single buffer. Note use of
22 // stat() to get the file size. This is a win32 function, believe it
23 // or not. :) Note the REALLY IMPORTANT use of the "b" flag to fopen.
24 // Text mode brain damage will kill us if we're trying to do bytewise
26 static char* readfile(const char* file, int* lenOut)
29 if(stat(file, &data) != 0) return 0;
30 FILE* f = fopen(file, "rb");
32 char* buf = new char[data.st_size];
33 *lenOut = fread(buf, 1, data.st_size, f);
35 if(*lenOut != data.st_size) {
36 // Shouldn't happen, but warn anyway since it represents a
37 // platform bug and not a typical runtime error (missing file,
39 SG_LOG(SG_NASAL, SG_ALERT,
40 "ERROR in Nasal initialization: " <<
41 "short count returned from fread() of " << file <<
42 ". Check your C library!");
49 FGNasalSys::FGNasalSys()
54 _nextGCKey = 0; // Any value will do
57 FGNasalSys::~FGNasalSys()
59 // Nasal doesn't have a "destroy context" API yet. :(
60 // Not a problem for a global subsystem that will never be
61 // destroyed. And the context is actually a global, so no memory
62 // is technically leaked (although the GC pool memory obviously
68 bool FGNasalSys::parseAndRun(const char* sourceCode)
70 naRef code = parse("FGNasalSys::parseAndRun()", sourceCode,
75 naCall(_context, code, 0, 0, naNil(), naNil());
77 if(!naGetError(_context)) return true;
82 FGNasalScript* FGNasalSys::parseScript(const char* src, const char* name)
84 FGNasalScript* script = new FGNasalScript();
85 script->_gcKey = -1; // important, if we delete it on a parse
86 script->_nas = this; // error, don't clobber a real handle!
90 sprintf(buf, "FGNasalScript@%p", script);
94 script->_code = parse(name, src, strlen(src));
95 if(naIsNil(script->_code)) {
100 script->_gcKey = gcSave(script->_code);
104 // Utility. Sets a named key in a hash by C string, rather than nasal
106 void FGNasalSys::hashset(naRef hash, const char* key, naRef val)
108 naRef s = naNewString(_context);
109 naStr_fromdata(s, (char*)key, strlen(key));
110 naHash_set(hash, s, val);
113 // The get/setprop functions accept a *list* of strings and walk
114 // through the property tree with them to find the appropriate node.
115 // This allows a Nasal object to hold onto a property path and use it
116 // like a node object, e.g. setprop(ObjRoot, "size-parsecs", 2.02). This
117 // is the utility function that walks the property tree.
118 // Future enhancement: support integer arguments to specify array
120 static SGPropertyNode* findnode(naContext c, naRef* vec, int len)
122 SGPropertyNode* p = globals->get_props();
123 for(int i=0; i<len; i++) {
125 if(!naIsString(a)) return 0;
126 p = p->getNode(naStr_data(a));
132 // getprop() extension function. Concatenates its string arguments as
133 // property names and returns the value of the specified property. Or
134 // nil if it doesn't exist.
135 static naRef f_getprop(naContext c, naRef me, int argc, naRef* args)
137 const SGPropertyNode* p = findnode(c, args, argc);
138 if(!p) return naNil();
140 switch(p->getType()) {
141 case SGPropertyNode::BOOL: case SGPropertyNode::INT:
142 case SGPropertyNode::LONG: case SGPropertyNode::FLOAT:
143 case SGPropertyNode::DOUBLE:
144 return naNum(p->getDoubleValue());
146 case SGPropertyNode::STRING:
147 case SGPropertyNode::UNSPECIFIED:
149 naRef nastr = naNewString(c);
150 const char* val = p->getStringValue();
151 naStr_fromdata(nastr, (char*)val, strlen(val));
154 case SGPropertyNode::ALIAS: // <--- FIXME, recurse?
160 // setprop() extension function. Concatenates its string arguments as
161 // property names and sets the value of the specified property to the
163 static naRef f_setprop(naContext c, naRef me, int argc, naRef* args)
166 char buf[BUFLEN + 1];
170 for(int i=0; i<argc-1; i++) {
171 naRef s = naStringValue(c, args[i]);
172 if(naIsNil(s)) return naNil();
173 strncpy(p, naStr_data(s), buflen);
175 buflen = BUFLEN - (p - buf);
176 if(i < (argc-2) && buflen > 0) {
182 SGPropertyNode* props = globals->get_props();
183 naRef val = args[argc-1];
184 if(naIsString(val)) props->setStringValue(buf, naStr_data(val));
185 else props->setDoubleValue(buf, naNumValue(val).num);
190 // print() extension function. Concatenates and prints its arguments
191 // to the FlightGear log. Uses the highest log level (SG_ALERT), to
192 // make sure it appears. Is there better way to do this?
193 static naRef f_print(naContext c, naRef me, int argc, naRef* args)
196 char buf[BUFLEN + 1];
197 buf[BUFLEN] = 0; // extra nul to handle strncpy brain damage
198 buf[0] = 0; // Zero-length in case there are no arguments
202 for(int i=0; i<n; i++) {
203 naRef s = naStringValue(c, args[i]);
204 if(naIsNil(s)) continue;
205 strncpy(p, naStr_data(s), buflen);
207 buflen = BUFLEN - (p - buf);
208 if(buflen <= 0) break;
210 SG_LOG(SG_GENERAL, SG_ALERT, buf);
215 // fgcommand() extension function. Executes a named command via the
216 // FlightGear command manager. Takes a single property node name as
218 static naRef f_fgcommand(naContext c, naRef me, int argc, naRef* args)
220 if(argc < 2 || !naIsString(args[0]) || !naIsGhost(args[1]))
221 naRuntimeError(c, "bad arguments to fgcommand()");
222 naRef cmd = args[0], props = args[1];
223 SGPropertyNode_ptr* node = (SGPropertyNode_ptr*)naGhost_ptr(props);
224 globals->get_commands()->execute(naStr_data(cmd), *node);
229 // settimer(func, dt, simtime) extension function. Falls through to
230 // FGNasalSys::setTimer(). See there for docs.
231 static naRef f_settimer(naContext c, naRef me, int argc, naRef* args)
233 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
234 nasal->setTimer(argc, args);
238 // setlistener(func, property) extension function. Falls through to
239 // FGNasalSys::setListener(). See there for docs.
240 static naRef f_setlistener(naContext c, naRef me, int argc, naRef* args)
242 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
243 nasal->setListener(argc, args);
247 // Returns a ghost handle to the argument to the currently executing
249 static naRef f_cmdarg(naContext c, naRef me, int argc, naRef* args)
251 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
252 return nasal->cmdArgGhost();
255 // Sets up a property interpolation. The first argument is either a
256 // ghost (SGPropertyNode_ptr*) or a string (global property path) to
257 // interpolate. The second argument is a vector of pairs of
258 // value/delta numbers.
259 static naRef f_interpolate(naContext c, naRef me, int argc, naRef* args)
261 SGPropertyNode* node;
262 naRef prop = argc > 0 ? args[0] : naNil();
263 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
264 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
267 naRef curve = argc > 1 ? args[1] : naNil();
268 if(!naIsVector(curve)) return naNil();
269 int nPoints = naVec_size(curve) / 2;
270 double* values = new double[nPoints];
271 double* deltas = new double[nPoints];
272 for(int i=0; i<nPoints; i++) {
273 values[i] = naNumValue(naVec_get(curve, 2*i)).num;
274 deltas[i] = naNumValue(naVec_get(curve, 2*i+1)).num;
277 ((SGInterpolator*)globals->get_subsystem("interpolator"))
278 ->interpolate(node, nPoints, values, deltas);
283 // This is a better RNG than the one in the default Nasal distribution
284 // (which is based on the C library rand() implementation). It will
286 static naRef f_rand(naContext c, naRef me, int argc, naRef* args)
288 return naNum(sg_random());
291 static naRef f_srand(naContext c, naRef me, int argc, naRef* args)
297 // Wrapper function for screenPrint
298 static naRef f_screenPrint(naContext c, naRef me, int argc, naRef* args)
300 if(argc != 1 || !naIsString(args[0]))
301 naRuntimeError(c, "bad arguments to screenPrint()");
302 naRef lmsg = args[0];
303 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
304 nasal->screenPrint(naStr_data(lmsg));
308 // Return an array listing of all files in a directory
309 static naRef f_directory(naContext c, naRef me, int argc, naRef* args)
311 if(argc != 1 || !naIsString(args[0]))
312 naRuntimeError(c, "bad arguments to directory()");
313 naRef ldir = args[0];
314 ulDir* dir = ulOpenDir(naStr_data(args[0]));
315 if(!dir) return naNil();
316 naRef result = naNewVector(c);
318 while((dent = ulReadDir(dir)))
319 naVec_append(result, naStr_fromdata(naNewString(c), dent->d_name,
320 strlen(dent->d_name)));
325 // Table of extension functions. Terminate with zeros.
326 static struct { char* name; naCFunction func; } funcs[] = {
327 { "getprop", f_getprop },
328 { "setprop", f_setprop },
329 { "print", f_print },
330 { "_fgcommand", f_fgcommand },
331 { "settimer", f_settimer },
332 { "_setlistener", f_setlistener },
333 { "_cmdarg", f_cmdarg },
334 { "_interpolate", f_interpolate },
336 { "srand", f_srand },
337 { "screenPrint", f_screenPrint },
338 { "directory", f_directory },
342 naRef FGNasalSys::cmdArgGhost()
344 return propNodeGhost(_cmdArg);
347 void FGNasalSys::init()
351 _context = naNewContext();
353 // Start with globals. Add it to itself as a recursive
354 // sub-reference under the name "globals". This gives client-code
355 // write access to the namespace if someone wants to do something
357 _globals = naStdLib(_context);
358 naSave(_context, _globals);
359 hashset(_globals, "globals", _globals);
361 // Add in the math library under "math"
362 hashset(_globals, "math", naMathLib(_context));
364 // Add our custom extension functions:
365 for(i=0; funcs[i].name; i++)
366 hashset(_globals, funcs[i].name,
367 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
369 // And our SGPropertyNode wrapper
370 hashset(_globals, "props", genPropsModule());
372 // Make a "__gcsave" hash to hold the naRef objects which get
373 // passed to handles outside the interpreter (to protect them from
374 // begin garbage-collected).
375 _gcHash = naNewHash(_context);
376 hashset(_globals, "__gcsave", _gcHash);
378 // Now load the various source files in the Nasal directory
379 SGPath p(globals->get_fg_root());
382 ulDir* dir = ulOpenDir(p.c_str());
383 while(dir && (dent = ulReadDir(dir)) != 0) {
385 fullpath.append(dent->d_name);
386 SGPath file(dent->d_name);
387 if(file.extension() != "nas") continue;
388 loadModule(fullpath, file.base().c_str());
391 // Pull scripts out of the property tree, too
392 loadPropertyScripts();
395 // Loads the scripts found under /nasal in the global tree
396 void FGNasalSys::loadPropertyScripts()
398 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
401 for(int i=0; i<nasal->nChildren(); i++) {
402 SGPropertyNode* n = nasal->getChild(i);
404 const char* module = n->getName();
405 if(n->hasChild("module"))
406 module = n->getStringValue("module");
408 // allow multiple files to be specified within in a single
412 bool file_specified = false;
413 while ( (fn = n->getChild("file", j)) != NULL ) {
414 file_specified = true;
415 const char* file = fn->getStringValue();
416 SGPath p(globals->get_fg_root());
418 loadModule(p, module);
422 // Old code which only allowed a single file to be specified per module
424 const char* file = n->getStringValue("file");
425 if(!n->hasChild("file")) file = 0; // Hrm...
427 SGPath p(globals->get_fg_root());
429 loadModule(p, module);
433 const char* src = n->getStringValue("script");
434 if(!n->hasChild("script")) src = 0; // Hrm...
436 createModule(module, n->getPath(), src, strlen(src));
438 if(!file_specified && !src)
439 SG_LOG(SG_NASAL, SG_ALERT, "Nasal error: " <<
440 "no <file> or <script> defined in " <<
441 "/nasal/" << module);
445 // Logs a runtime error, with stack trace, to the FlightGear log stream
446 void FGNasalSys::logError()
448 SG_LOG(SG_NASAL, SG_ALERT,
449 "Nasal runtime error: " << naGetError(_context));
450 SG_LOG(SG_NASAL, SG_ALERT,
451 " at " << naStr_data(naGetSourceFile(_context, 0)) <<
452 ", line " << naGetLine(_context, 0));
453 for(int i=1; i<naStackDepth(_context); i++)
454 SG_LOG(SG_NASAL, SG_ALERT,
455 " called from: " << naStr_data(naGetSourceFile(_context, i)) <<
456 ", line " << naGetLine(_context, i));
459 // Reads a script file, executes it, and places the resulting
460 // namespace into the global namespace under the specified module
462 void FGNasalSys::loadModule(SGPath file, const char* module)
465 char* buf = readfile(file.c_str(), &len);
467 SG_LOG(SG_NASAL, SG_ALERT,
468 "Nasal error: could not read script file " << file.c_str()
469 << " into module " << module);
473 createModule(module, file.c_str(), buf, len);
477 // Parse and run. Save the local variables namespace, as it will
478 // become a sub-object of globals.
479 void FGNasalSys::createModule(const char* moduleName, const char* fileName,
480 const char* src, int len)
482 naRef code = parse(fileName, src, len);
486 // See if we already have a module hash to use. This allows the
487 // user to, for example, add functions to the built-in math
488 // module. Make a new one if necessary.
490 naRef modname = naNewString(_context);
491 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
492 if(!naHash_get(_globals, modname, &locals))
493 locals = naNewHash(_context);
495 naCall(_context, code, 0, 0, naNil(), locals);
496 if(naGetError(_context)) {
500 hashset(_globals, moduleName, locals);
503 naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
506 naRef srcfile = naNewString(_context);
507 naStr_fromdata(srcfile, (char*)filename, strlen(filename));
508 naRef code = naParseCode(_context, srcfile, 1, (char*)buf, len, &errLine);
510 SG_LOG(SG_NASAL, SG_ALERT,
511 "Nasal parse error: " << naGetError(_context) <<
512 " in "<< filename <<", line " << errLine);
516 // Bind to the global namespace before returning
517 return naBindFunction(_context, code, _globals);
520 bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
522 const char* nasal = arg->getStringValue("script");
523 const char* moduleName = arg->getStringValue("module");
524 naRef code = parse(arg->getPath(true), nasal, strlen(nasal));
525 if(naIsNil(code)) return false;
527 naRef locals = naNil();
529 naRef modname = naNewString(_context);
530 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
531 if(!naHash_get(_globals, modname, &locals))
532 locals = naNewHash(_context);
534 // Cache the command argument for inspection via cmdarg(). For
535 // performance reasons, we won't bother with it if the invoked
536 // code doesn't need it.
537 _cmdArg = (SGPropertyNode*)arg;
540 naRef result = naCall(_context, code, 0, 0, naNil(), locals);
541 if(!naGetError(_context)) return true;
546 // settimer(func, dt, simtime) extension function. The first argument
547 // is a Nasal function to call, the second is a delta time (from now),
548 // in seconds. The third, if present, is a boolean value indicating
549 // that "real world" time (rather than simulator time) is to be used.
551 // Implementation note: the FGTimer objects don't live inside the
552 // garbage collector, so the Nasal handler functions have to be
553 // "saved" somehow lest they be inadvertently cleaned. In this case,
554 // they are inserted into a globals.__gcsave hash and removed on
556 void FGNasalSys::setTimer(int argc, naRef* args)
558 // Extract the handler, delta, and simtime arguments:
559 naRef handler = argc > 0 ? args[0] : naNil();
560 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
563 naRef delta = argc > 1 ? args[1] : naNil();
564 if(naIsNil(delta)) return;
566 bool simtime = (argc > 2 && naTrue(args[2])) ? false : true;
568 // Generate and register a C++ timer handler
569 NasalTimer* t = new NasalTimer;
570 t->handler = handler;
571 t->gcKey = gcSave(handler);
574 globals->get_event_mgr()->addEvent("NasalTimer",
575 t, &NasalTimer::timerExpired,
579 void FGNasalSys::handleTimer(NasalTimer* t)
581 naCall(_context, t->handler, 0, 0, naNil(), naNil());
582 if(naGetError(_context))
587 int FGNasalSys::gcSave(naRef r)
589 int key = _nextGCKey++;
590 naHash_set(_gcHash, naNum(key), r);
594 void FGNasalSys::gcRelease(int key)
596 naHash_delete(_gcHash, naNum(key));
599 void FGNasalSys::NasalTimer::timerExpired()
601 nasal->handleTimer(this);
605 // setlistener(property, func) extension function. The first argument
606 // is either a ghost (SGPropertyNode_ptr*) or a string (global property
607 // path), the second is a Nasal function.
608 void FGNasalSys::setListener(int argc, naRef* args)
610 SGPropertyNode* node;
611 naRef prop = argc > 0 ? args[0] : naNil();
612 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
613 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
616 naRef handler = argc > 1 ? args[1] : naNil();
617 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
620 node->addChangeListener(new FGNasalListener(handler, this, gcSave(handler)));
623 // functions providing access to the NasalDisplay - used to display text directly on the screen
624 void FGNasalSys::screenPrint(const char* src)
626 globals->get_Nasal_display()->RegisterSingleMessage(src, 0);