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"
20 // Read and return file contents in a single buffer. Note use of
21 // stat() to get the file size. This is a win32 function, believe it
22 // or not. :) Note the REALLY IMPORTANT use of the "b" flag to fopen.
23 // Text mode brain damage will kill us if we're trying to do bytewise
25 static char* readfile(const char* file, int* lenOut)
28 if(stat(file, &data) != 0) return 0;
29 FILE* f = fopen(file, "rb");
31 char* buf = new char[data.st_size];
32 *lenOut = fread(buf, 1, data.st_size, f);
34 if(*lenOut != data.st_size) {
35 // Shouldn't happen, but warn anyway since it represents a
36 // platform bug and not a typical runtime error (missing file,
38 SG_LOG(SG_NASAL, SG_ALERT,
39 "ERROR in Nasal initialization: " <<
40 "short count returned from fread() of " << file <<
41 ". Check your C library!");
48 FGNasalSys::FGNasalSys()
53 _nextGCKey = 0; // Any value will do
56 FGNasalSys::~FGNasalSys()
58 // Nasal doesn't have a "destroy context" API yet. :(
59 // Not a problem for a global subsystem that will never be
60 // destroyed. And the context is actually a global, so no memory
61 // is technically leaked (although the GC pool memory obviously
67 bool FGNasalSys::parseAndRun(const char* sourceCode)
69 naRef code = parse("FGNasalSys::parseAndRun()", sourceCode,
74 naCall(_context, code, naNil(), naNil(), naNil());
76 if(!naGetError(_context)) return true;
81 FGNasalScript* FGNasalSys::parseScript(const char* src, const char* name)
83 FGNasalScript* script = new FGNasalScript();
84 script->_gcKey = -1; // important, if we delete it on a parse
85 script->_nas = this; // error, don't clobber a real handle!
89 sprintf(buf, "FGNasalScript@%8.8x", (int)script);
93 script->_code = parse(name, src);
94 if(naIsNil(script->_code)) {
99 script->_gcKey = gcSave(script->_code);
103 // Utility. Sets a named key in a hash by C string, rather than nasal
105 void FGNasalSys::hashset(naRef hash, const char* key, naRef val)
107 naRef s = naNewString(_context);
108 naStr_fromdata(s, (char*)key, strlen(key));
109 naHash_set(hash, s, val);
112 // The get/setprop functions accept a *list* of strings and walk
113 // through the property tree with them to find the appropriate node.
114 // This allows a Nasal object to hold onto a property path and use it
115 // like a node object, e.g. setprop(ObjRoot, "size-parsecs", 2.02). This
116 // is the utility function that walks the property tree.
117 // Future enhancement: support integer arguments to specify array
119 static SGPropertyNode* findnode(naContext c, naRef* vec, int len)
121 SGPropertyNode* p = globals->get_props();
122 for(int i=0; i<len; i++) {
124 if(!naIsString(a)) return 0;
125 p = p->getNode(naStr_data(a));
131 // getprop() extension function. Concatenates its string arguments as
132 // property names and returns the value of the specified property. Or
133 // nil if it doesn't exist.
134 static naRef f_getprop(naContext c, naRef me, int argc, naRef* args)
136 const SGPropertyNode* p = findnode(c, args, argc);
137 if(!p) return naNil();
139 switch(p->getType()) {
140 case SGPropertyNode::BOOL: case SGPropertyNode::INT:
141 case SGPropertyNode::LONG: case SGPropertyNode::FLOAT:
142 case SGPropertyNode::DOUBLE:
143 return naNum(p->getDoubleValue());
145 case SGPropertyNode::STRING:
146 case SGPropertyNode::UNSPECIFIED:
148 naRef nastr = naNewString(c);
149 const char* val = p->getStringValue();
150 naStr_fromdata(nastr, (char*)val, strlen(val));
153 case SGPropertyNode::ALIAS: // <--- FIXME, recurse?
159 // setprop() extension function. Concatenates its string arguments as
160 // property names and sets the value of the specified property to the
162 static naRef f_setprop(naContext c, naRef me, int argc, naRef* args)
165 char buf[BUFLEN + 1];
169 for(int i=0; i<argc-1; i++) {
170 naRef s = naStringValue(c, args[i]);
171 if(naIsNil(s)) return naNil();
172 strncpy(p, naStr_data(s), buflen);
174 buflen = BUFLEN - (p - buf);
175 if(i < (argc-2) && buflen > 0) {
181 SGPropertyNode* props = globals->get_props();
182 naRef val = args[argc-1];
183 if(naIsString(val)) props->setStringValue(buf, naStr_data(val));
184 else props->setDoubleValue(buf, naNumValue(val).num);
189 // print() extension function. Concatenates and prints its arguments
190 // to the FlightGear log. Uses the highest log level (SG_ALERT), to
191 // make sure it appears. Is there better way to do this?
192 static naRef f_print(naContext c, naRef me, int argc, naRef* args)
195 char buf[BUFLEN + 1];
196 buf[BUFLEN] = 0; // extra nul to handle strncpy brain damage
197 buf[0] = 0; // Zero-length in case there are no arguments
201 for(int i=0; i<n; i++) {
202 naRef s = naStringValue(c, args[i]);
203 if(naIsNil(s)) continue;
204 strncpy(p, naStr_data(s), buflen);
206 buflen = BUFLEN - (p - buf);
207 if(buflen <= 0) break;
209 SG_LOG(SG_GENERAL, SG_ALERT, buf);
214 // fgcommand() extension function. Executes a named command via the
215 // FlightGear command manager. Takes a single property node name as
217 static naRef f_fgcommand(naContext c, naRef me, int argc, naRef* args)
219 if(argc < 2 || !naIsString(args[0]) || !naIsGhost(args[1]))
220 naRuntimeError(c, "bad arguments to fgcommand()");
221 naRef cmd = args[0], props = args[1];
222 SGPropertyNode_ptr* node = (SGPropertyNode_ptr*)naGhost_ptr(props);
223 globals->get_commands()->execute(naStr_data(cmd), *node);
228 // settimer(func, dt, simtime) extension function. Falls through to
229 // FGNasalSys::setTimer(). See there for docs.
230 static naRef f_settimer(naContext c, naRef me, int argc, naRef* args)
232 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
233 nasal->setTimer(argc, args);
237 // Returns a ghost handle to the argument to the currently executing
239 static naRef f_cmdarg(naContext c, naRef me, int argc, naRef* args)
241 FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
242 return nasal->cmdArgGhost();
245 // Sets up a property interpolation. The first argument is either a
246 // ghost (SGPropertyNode_ptr*) or a string (global property path) to
247 // interpolate. The second argument is a vector of pairs of
248 // value/delta numbers.
249 static naRef f_interpolate(naContext c, naRef me, int argc, naRef* args)
251 SGPropertyNode* node;
252 naRef prop = argc > 0 ? args[0] : naNil();
253 if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
254 else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
257 naRef curve = argc > 1 ? args[1] : naNil();
258 if(!naIsVector(curve)) return naNil();
259 int nPoints = naVec_size(curve) / 2;
260 double* values = new double[nPoints];
261 double* deltas = new double[nPoints];
262 for(int i=0; i<nPoints; i++) {
263 values[i] = naNumValue(naVec_get(curve, 2*i)).num;
264 deltas[i] = naNumValue(naVec_get(curve, 2*i+1)).num;
267 ((SGInterpolator*)globals->get_subsystem("interpolator"))
268 ->interpolate(node, nPoints, values, deltas);
273 // This is a better RNG than the one in the default Nasal distribution
274 // (which is based on the C library rand() implementation). It will
276 static naRef f_rand(naContext c, naRef me, int argc, naRef* args)
278 return naNum(sg_random());
281 // Table of extension functions. Terminate with zeros.
282 static struct { char* name; naCFunction func; } funcs[] = {
283 { "getprop", f_getprop },
284 { "setprop", f_setprop },
285 { "print", f_print },
286 { "_fgcommand", f_fgcommand },
287 { "settimer", f_settimer },
288 { "_cmdarg", f_cmdarg },
289 { "_interpolate", f_interpolate },
294 naRef FGNasalSys::cmdArgGhost()
296 return propNodeGhost(_cmdArg);
299 void FGNasalSys::init()
303 _context = naNewContext();
305 // Start with globals. Add it to itself as a recursive
306 // sub-reference under the name "globals". This gives client-code
307 // write access to the namespace if someone wants to do something
309 _globals = naStdLib(_context);
310 naSave(_context, _globals);
311 hashset(_globals, "globals", _globals);
313 // Add in the math library under "math"
314 hashset(_globals, "math", naMathLib(_context));
316 // Add our custom extension functions:
317 for(i=0; funcs[i].name; i++)
318 hashset(_globals, funcs[i].name,
319 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
321 // And our SGPropertyNode wrapper
322 hashset(_globals, "props", genPropsModule());
324 // Make a "__gcsave" hash to hold the naRef objects which get
325 // passed to handles outside the interpreter (to protect them from
326 // begin garbage-collected).
327 _gcHash = naNewHash(_context);
328 hashset(_globals, "__gcsave", _gcHash);
330 // Now load the various source files in the Nasal directory
331 SGPath p(globals->get_fg_root());
334 ulDir* dir = ulOpenDir(p.c_str());
335 while(dir && (dent = ulReadDir(dir)) != 0) {
337 fullpath.append(dent->d_name);
338 SGPath file(dent->d_name);
339 if(file.extension() != "nas") continue;
340 readScriptFile(fullpath, file.base().c_str());
343 // Pull scripts out of the property tree, too
344 loadPropertyScripts();
347 // Loads the scripts found under /nasal in the global tree
348 void FGNasalSys::loadPropertyScripts()
350 SGPropertyNode* nasal = globals->get_props()->getNode("nasal");
353 for(int i=0; i<nasal->nChildren(); i++) {
354 SGPropertyNode* n = nasal->getChild(i);
356 const char* module = n->getName();
357 if(n->hasChild("module"))
358 module = n->getStringValue("module");
360 // allow multiple files to be specified within in a single
364 bool file_specified = false;
365 while ( (fn = n->getChild("file", j)) != NULL ) {
366 file_specified = true;
367 const char* file = fn->getStringValue();
368 SGPath p(globals->get_fg_root());
370 readScriptFile(p, module);
374 // Old code which only allowed a single file to be specified per module
376 const char* file = n->getStringValue("file");
377 if(!n->hasChild("file")) file = 0; // Hrm...
379 SGPath p(globals->get_fg_root());
381 readScriptFile(p, module);
385 const char* src = n->getStringValue("script");
386 if(!n->hasChild("script")) src = 0; // Hrm...
388 initModule(module, n->getPath(), src, strlen(src));
390 if(!file_specified && !src)
391 SG_LOG(SG_NASAL, SG_ALERT, "Nasal error: " <<
392 "no <file> or <script> defined in " <<
393 "/nasal/" << module);
397 // Logs a runtime error, with stack trace, to the FlightGear log stream
398 void FGNasalSys::logError()
400 SG_LOG(SG_NASAL, SG_ALERT,
401 "Nasal runtime error: " << naGetError(_context));
402 SG_LOG(SG_NASAL, SG_ALERT,
403 " at " << naStr_data(naGetSourceFile(_context, 0)) <<
404 ", line " << naGetLine(_context, 0));
405 for(int i=1; i<naStackDepth(_context); i++)
406 SG_LOG(SG_NASAL, SG_ALERT,
407 " called from: " << naStr_data(naGetSourceFile(_context, i)) <<
408 ", line " << naGetLine(_context, i));
411 // Reads a script file, executes it, and places the resulting
412 // namespace into the global namespace under the specified module
414 void FGNasalSys::readScriptFile(SGPath file, const char* module)
417 char* buf = readfile(file.c_str(), &len);
419 SG_LOG(SG_NASAL, SG_ALERT,
420 "Nasal error: could not read script file " << file.c_str()
421 << " into module " << module);
425 initModule(module, file.c_str(), buf, len);
429 // Parse and run. Save the local variables namespace, as it will
430 // become a sub-object of globals.
431 void FGNasalSys::initModule(const char* moduleName, const char* fileName,
432 const char* src, int len)
434 naRef code = parse(fileName, src, len);
438 // See if we already have a module hash to use. This allows the
439 // user to, for example, add functions to the built-in math
440 // module. Make a new one if necessary.
442 naRef modname = naNewString(_context);
443 naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
444 if(!naHash_get(_globals, modname, &locals))
445 locals = naNewHash(_context);
447 naCall(_context, code, naNil(), naNil(), locals);
448 if(naGetError(_context)) {
452 hashset(_globals, moduleName, locals);
455 naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
457 if(len == 0) len = strlen(buf);
459 naRef srcfile = naNewString(_context);
460 naStr_fromdata(srcfile, (char*)filename, strlen(filename));
461 naRef code = naParseCode(_context, srcfile, 1, (char*)buf, len, &errLine);
463 SG_LOG(SG_NASAL, SG_ALERT,
464 "Nasal parse error: " << naGetError(_context) <<
465 " in "<< filename <<", line " << errLine);
469 // Bind to the global namespace before returning
470 return naBindFunction(_context, code, _globals);
473 bool FGNasalSys::handleCommand(const SGPropertyNode* arg)
475 // Parse the Nasal source. I'd love to use the property name of
476 // the argument, but it's actually a *clone* of the original
477 // location in the property tree. arg->getPath() returns an empty
479 const char* nasal = arg->getStringValue("script");
480 naRef code = parse("<command>", nasal);
481 if(naIsNil(code)) return false;
483 // Cache the command argument for inspection via cmdarg(). For
484 // performance reasons, we won't bother with it if the invoked
485 // code doesn't need it.
486 _cmdArg = (SGPropertyNode*)arg;
489 naRef result = naCall(_context, code, naNil(), naNil(), naNil());
490 if(!naGetError(_context)) return true;
495 // settimer(func, dt, simtime) extension function. The first argument
496 // is a Nasal function to call, the second is a delta time (from now),
497 // in seconds. The third, if present, is a boolean value indicating
498 // that "simulator" time (rather than real time) is to be used.
500 // Implementation note: the FGTimer objects don't live inside the
501 // garbage collector, so the Nasal handler functions have to be
502 // "saved" somehow lest they be inadvertently cleaned. In this case,
503 // they are inserted into a globals.__gcsave hash and removed on
505 void FGNasalSys::setTimer(int argc, naRef* args)
507 // Extract the handler, delta, and simtime arguments:
508 naRef handler = argc > 0 ? args[0] : naNil();
509 if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
512 naRef delta = argc > 1 ? args[1] : naNil();
513 if(naIsNil(delta)) return;
515 bool simtime = (argc > 2 && naTrue(args[2])) ? true : false;
517 // Generate and register a C++ timer handler
518 NasalTimer* t = new NasalTimer;
519 t->handler = handler;
520 t->gcKey = gcSave(handler);
523 globals->get_event_mgr()->addEvent("NasalTimer",
524 t, &NasalTimer::timerExpired,
528 void FGNasalSys::handleTimer(NasalTimer* t)
530 naCall(_context, t->handler, naNil(), naNil(), naNil());
531 if(naGetError(_context))
536 int FGNasalSys::gcSave(naRef r)
538 int key = _nextGCKey++;
539 naHash_set(_gcHash, naNum(key), r);
543 void FGNasalSys::gcRelease(int key)
545 naHash_delete(_gcHash, naNum(key));
548 void FGNasalSys::NasalTimer::timerExpired()
550 nasal->handleTimer(this);