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 // Wrapper function for screenPrint
292 static naRef f_screenPrint(naContext c, naRef me, int argc, naRef* args)
294 if(argc != 1 || !naIsString(args[0]))
295 naRuntimeError(c, "bad arguments to screenPrint()");
296 naRef lmsg = args[0];
297 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
298 nasal->screenPrint(naStr_data(lmsg));
302 // Return an array listing of all files in a directory
303 static naRef f_directory(naContext c, naRef me, int argc, naRef* args)
305 if(argc != 1 || !naIsString(args[0]))
306 naRuntimeError(c, "bad arguments to directory()");
307 naRef ldir = args[0];
308 ulDir* dir = ulOpenDir(naStr_data(args[0]));
309 if(!dir) return naNil();
310 naRef result = naNewVector(c);
312 while((dent = ulReadDir(dir)))
313 naVec_append(result, naStr_fromdata(naNewString(c), dent->d_name,
314 strlen(dent->d_name)));
319 // Table of extension functions. Terminate with zeros.
320 static struct { char* name; naCFunction func; } funcs[] = {
321 { "getprop", f_getprop },
322 { "setprop", f_setprop },
323 { "print", f_print },
324 { "_fgcommand", f_fgcommand },
325 { "settimer", f_settimer },
326 { "_setlistener", f_setlistener },
327 { "_cmdarg", f_cmdarg },
328 { "_interpolate", f_interpolate },
330 { "screenPrint", f_screenPrint },
331 { "directory", f_directory },
335 naRef FGNasalSys::cmdArgGhost()
337 return propNodeGhost(_cmdArg);
340 void FGNasalSys::init()
344 _context = naNewContext();
346 // Start with globals. Add it to itself as a recursive
347 // sub-reference under the name "globals". This gives client-code
348 // write access to the namespace if someone wants to do something
350 _globals = naStdLib(_context);
351 naSave(_context, _globals);
352 hashset(_globals, "globals", _globals);
354 // Add in the math library under "math"
355 hashset(_globals, "math", naMathLib(_context));
357 // Add our custom extension functions:
358 for(i=0; funcs[i].name; i++)
359 hashset(_globals, funcs[i].name,
360 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
362 // And our SGPropertyNode wrapper
363 hashset(_globals, "props", genPropsModule());
365 // Make a "__gcsave" hash to hold the naRef objects which get
366 // passed to handles outside the interpreter (to protect them from
367 // begin garbage-collected).
368 _gcHash = naNewHash(_context);
369 hashset(_globals, "__gcsave", _gcHash);
371 // Now load the various source files in the Nasal directory
372 SGPath p(globals->get_fg_root());
375 ulDir* dir = ulOpenDir(p.c_str());
376 while(dir && (dent = ulReadDir(dir)) != 0) {
378 fullpath.append(dent->d_name);
379 SGPath file(dent->d_name);
380 if(file.extension() != "nas") continue;
381 loadModule(fullpath, file.base().c_str());
384 // Pull scripts out of the property tree, too
385 loadPropertyScripts();
388 // Loads the scripts found under /nasal in the global tree
389 void FGNasalSys::loadPropertyScripts()
391 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
394 for(int i=0; i<nasal->nChildren(); i++) {
395 SGPropertyNode* n = nasal->getChild(i);
397 const char* module = n->getName();
398 if(n->hasChild("module"))
399 module = n->getStringValue("module");
401 // allow multiple files to be specified within in a single
405 bool file_specified = false;
406 while ( (fn = n->getChild("file", j)) != NULL ) {
407 file_specified = true;
408 const char* file = fn->getStringValue();
409 SGPath p(globals->get_fg_root());
411 loadModule(p, module);
415 // Old code which only allowed a single file to be specified per module
417 const char* file = n->getStringValue("file");
418 if(!n->hasChild("file")) file = 0; // Hrm...
420 SGPath p(globals->get_fg_root());
422 loadModule(p, module);
426 const char* src = n->getStringValue("script");
427 if(!n->hasChild("script")) src = 0; // Hrm...
429 createModule(module, n->getPath(), src, strlen(src));
431 if(!file_specified && !src)
432 SG_LOG(SG_NASAL, SG_ALERT, "Nasal error: " <<
433 "no <file> or <script> defined in " <<
434 "/nasal/" << module);
438 // Logs a runtime error, with stack trace, to the FlightGear log stream
439 void FGNasalSys::logError()
441 SG_LOG(SG_NASAL, SG_ALERT,
442 "Nasal runtime error: " << naGetError(_context));
443 SG_LOG(SG_NASAL, SG_ALERT,
444 " at " << naStr_data(naGetSourceFile(_context, 0)) <<
445 ", line " << naGetLine(_context, 0));
446 for(int i=1; i<naStackDepth(_context); i++)
447 SG_LOG(SG_NASAL, SG_ALERT,
448 " called from: " << naStr_data(naGetSourceFile(_context, i)) <<
449 ", line " << naGetLine(_context, i));
452 // Reads a script file, executes it, and places the resulting
453 // namespace into the global namespace under the specified module
455 void FGNasalSys::loadModule(SGPath file, const char* module)
458 char* buf = readfile(file.c_str(), &len);
460 SG_LOG(SG_NASAL, SG_ALERT,
461 "Nasal error: could not read script file " << file.c_str()
462 << " into module " << module);
466 createModule(module, file.c_str(), buf, len);
470 // Parse and run. Save the local variables namespace, as it will
471 // become a sub-object of globals.
472 void FGNasalSys::createModule(const char* moduleName, const char* fileName,
473 const char* src, int len)
475 naRef code = parse(fileName, src, len);
479 // See if we already have a module hash to use. This allows the
480 // user to, for example, add functions to the built-in math
481 // module. Make a new one if necessary.
483 naRef modname = naNewString(_context);
484 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
485 if(!naHash_get(_globals, modname, &locals))
486 locals = naNewHash(_context);
488 naCall(_context, code, 0, 0, naNil(), locals);
489 if(naGetError(_context)) {
493 hashset(_globals, moduleName, locals);
496 naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
499 naRef srcfile = naNewString(_context);
500 naStr_fromdata(srcfile, (char*)filename, strlen(filename));
501 naRef code = naParseCode(_context, srcfile, 1, (char*)buf, len, &errLine);
503 SG_LOG(SG_NASAL, SG_ALERT,
504 "Nasal parse error: " << naGetError(_context) <<
505 " in "<< filename <<", line " << errLine);
509 // Bind to the global namespace before returning
510 return naBindFunction(_context, code, _globals);
513 bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
515 const char* nasal = arg->getStringValue("script");
516 const char* moduleName = arg->getStringValue("module");
517 naRef code = parse(arg->getPath(true), nasal, strlen(nasal));
518 if(naIsNil(code)) return false;
520 naRef locals = naNil();
522 naRef modname = naNewString(_context);
523 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
524 if(!naHash_get(_globals, modname, &locals))
525 locals = naNewHash(_context);
527 // Cache the command argument for inspection via cmdarg(). For
528 // performance reasons, we won't bother with it if the invoked
529 // code doesn't need it.
530 _cmdArg = (SGPropertyNode*)arg;
533 naRef result = naCall(_context, code, 0, 0, naNil(), locals);
534 if(!naGetError(_context)) return true;
539 // settimer(func, dt, simtime) extension function. The first argument
540 // is a Nasal function to call, the second is a delta time (from now),
541 // in seconds. The third, if present, is a boolean value indicating
542 // that "real world" time (rather than simulator time) is to be used.
544 // Implementation note: the FGTimer objects don't live inside the
545 // garbage collector, so the Nasal handler functions have to be
546 // "saved" somehow lest they be inadvertently cleaned. In this case,
547 // they are inserted into a globals.__gcsave hash and removed on
549 void FGNasalSys::setTimer(int argc, naRef* args)
551 // Extract the handler, delta, and simtime arguments:
552 naRef handler = argc > 0 ? args[0] : naNil();
553 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
556 naRef delta = argc > 1 ? args[1] : naNil();
557 if(naIsNil(delta)) return;
559 bool simtime = (argc > 2 && naTrue(args[2])) ? false : true;
561 // Generate and register a C++ timer handler
562 NasalTimer* t = new NasalTimer;
563 t->handler = handler;
564 t->gcKey = gcSave(handler);
567 globals->get_event_mgr()->addEvent("NasalTimer",
568 t, &NasalTimer::timerExpired,
572 void FGNasalSys::handleTimer(NasalTimer* t)
574 naCall(_context, t->handler, 0, 0, naNil(), naNil());
575 if(naGetError(_context))
580 int FGNasalSys::gcSave(naRef r)
582 int key = _nextGCKey++;
583 naHash_set(_gcHash, naNum(key), r);
587 void FGNasalSys::gcRelease(int key)
589 naHash_delete(_gcHash, naNum(key));
592 void FGNasalSys::NasalTimer::timerExpired()
594 nasal->handleTimer(this);
598 // setlistener(property, func) extension function. The first argument
599 // is either a ghost (SGPropertyNode_ptr*) or a string (global property
600 // path), the second is a Nasal function.
601 void FGNasalSys::setListener(int argc, naRef* args)
603 SGPropertyNode* node;
604 naRef prop = argc > 0 ? args[0] : naNil();
605 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
606 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
609 naRef handler = argc > 1 ? args[1] : naNil();
610 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
613 node->addChangeListener(new FGNasalListener(handler, this, gcSave(handler)));
616 // functions providing access to the NasalDisplay - used to display text directly on the screen
617 void FGNasalSys::screenPrint(const char* src)
619 globals->get_Nasal_display()->RegisterSingleMessage(src, 0);