+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#ifdef HAVE_SYS_TIME_H
+# include <sys/time.h> // gettimeofday
+#endif
+
#include <string.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
+#include <fstream>
#include <plib/ul.h>
#include <simgear/math/sg_random.h>
#include <simgear/misc/sg_path.hxx>
#include <simgear/misc/interpolator.hxx>
+#include <simgear/scene/material/mat.hxx>
#include <simgear/structure/commands.hxx>
+#include <simgear/math/sg_geodesy.hxx>
#include <Main/globals.hxx>
#include <Main/fg_props.hxx>
+#include <Scenery/scenery.hxx>
#include "NasalSys.hxx"
+static FGNasalSys* nasalSys = 0;
+
+
// Read and return file contents in a single buffer. Note use of
// stat() to get the file size. This is a win32 function, believe it
// or not. :) Note the REALLY IMPORTANT use of the "b" flag to fopen.
FGNasalSys::FGNasalSys()
{
+ nasalSys = this;
_context = 0;
_globals = naNil();
_gcHash = naNil();
_nextGCKey = 0; // Any value will do
+ _callCount = 0;
+ _purgeListeners = false;
+}
+
+// Does a naCall() in a new context. Wrapped here to make lock
+// tracking easier. Extension functions are called with the lock, but
+// we have to release it before making a new naCall(). So rather than
+// drop the lock in every extension function that might call back into
+// Nasal, we keep a stack depth counter here and only unlock/lock
+// around the naCall if it isn't the first one.
+naRef FGNasalSys::call(naRef code, naRef locals)
+{
+ naContext ctx = naNewContext();
+ if(_callCount) naModUnlock();
+ _callCount++;
+ naRef result = naCall(ctx, code, 0, 0, naNil(), locals);
+ if(naGetError(ctx))
+ logError(ctx);
+ _callCount--;
+ if(_callCount) naModLock();
+ naFreeContext(ctx);
+ return result;
}
FGNasalSys::~FGNasalSys()
{
- // Nasal doesn't have a "destroy context" API yet. :(
- // Not a problem for a global subsystem that will never be
- // destroyed. And the context is actually a global, so no memory
- // is technically leaked (although the GC pool memory obviously
- // won't be freed).
- _context = 0;
+ nasalSys = 0;
+ map<int, FGNasalListener *>::iterator it, end = _listener.end();
+ for(it = _listener.begin(); it != end; ++it)
+ delete it->second;
+
+ naFreeContext(_context);
_globals = naNil();
}
strlen(sourceCode));
if(naIsNil(code))
return false;
-
- naCall(_context, code, 0, 0, naNil(), naNil());
-
- if(!naGetError(_context)) return true;
- logError(_context);
- return false;
+ call(code, naNil());
+ return true;
}
FGNasalScript* FGNasalSys::parseScript(const char* src, const char* name)
char buf[256];
if(!name) {
- sprintf(buf, "FGNasalScript@%p", script);
+ sprintf(buf, "FGNasalScript@%p", (void *)script);
name = buf;
}
static SGPropertyNode* findnode(naContext c, naRef* vec, int len)
{
SGPropertyNode* p = globals->get_props();
- for(int i=0; i<len; i++) {
- naRef a = vec[i];
- if(!naIsString(a)) return 0;
- p = p->getNode(naStr_data(a));
- if(p == 0) return 0;
+ try {
+ for(int i=0; i<len; i++) {
+ naRef a = vec[i];
+ if(!naIsString(a)) return 0;
+ p = p->getNode(naStr_data(a));
+ if(p == 0) return 0;
+ }
+ } catch (const string& err) {
+ naRuntimeError(c, (char *)err.c_str());
+ return 0;
}
return p;
}
SGPropertyNode* props = globals->get_props();
naRef val = args[argc-1];
- if(naIsString(val)) props->setStringValue(buf, naStr_data(val));
- else props->setDoubleValue(buf, naNumValue(val).num);
+ try {
+ if(naIsString(val)) props->setStringValue(buf, naStr_data(val));
+ else {
+ naRef n = naNumValue(val);
+ if(naIsNil(n))
+ naRuntimeError(c, "setprop() value is not string or number");
+ props->setDoubleValue(buf, n.num);
+ }
+ } catch (const string& err) {
+ naRuntimeError(c, (char *)err.c_str());
+ }
return naNil();
#undef BUFLEN
}
// make sure it appears. Is there better way to do this?
static naRef f_print(naContext c, naRef me, int argc, naRef* args)
{
-#define BUFLEN 1024
- char buf[BUFLEN + 1];
- buf[BUFLEN] = 0; // extra nul to handle strncpy brain damage
- buf[0] = 0; // Zero-length in case there are no arguments
- char* p = buf;
- int buflen = BUFLEN;
+ string buf;
int n = argc;
for(int i=0; i<n; i++) {
naRef s = naStringValue(c, args[i]);
if(naIsNil(s)) continue;
- strncpy(p, naStr_data(s), buflen);
- p += naStr_len(s);
- buflen = BUFLEN - (p - buf);
- if(buflen <= 0) break;
+ buf += naStr_data(s);
}
SG_LOG(SG_GENERAL, SG_ALERT, buf);
- return naNil();
-#undef BUFLEN
+ return naNum(buf.length());
}
// fgcommand() extension function. Executes a named command via the
// an argument.
static naRef f_fgcommand(naContext c, naRef me, int argc, naRef* args)
{
- if(argc < 2 || !naIsString(args[0]) || !naIsGhost(args[1]))
+ naRef cmd = argc > 0 ? args[0] : naNil();
+ naRef props = argc > 1 ? args[1] : naNil();
+ if(!naIsString(cmd) || (!naIsNil(props) && !naIsGhost(props)))
naRuntimeError(c, "bad arguments to fgcommand()");
- naRef cmd = args[0], props = args[1];
- SGPropertyNode_ptr* node = (SGPropertyNode_ptr*)naGhost_ptr(props);
- globals->get_commands()->execute(naStr_data(cmd), *node);
- return naNil();
-
+ SGPropertyNode_ptr tmp, *node;
+ if(!naIsNil(props))
+ node = (SGPropertyNode_ptr*)naGhost_ptr(props);
+ else {
+ tmp = new SGPropertyNode();
+ node = &tmp;
+ }
+ return naNum(globals->get_commands()->execute(naStr_data(cmd), *node));
}
// settimer(func, dt, simtime) extension function. Falls through to
// FGNasalSys::setTimer(). See there for docs.
static naRef f_settimer(naContext c, naRef me, int argc, naRef* args)
{
- FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
- nasal->setTimer(argc, args);
+ nasalSys->setTimer(c, argc, args);
return naNil();
}
-// setlistener(func, property) extension function. Falls through to
+// setlistener(func, property, bool) extension function. Falls through to
// FGNasalSys::setListener(). See there for docs.
static naRef f_setlistener(naContext c, naRef me, int argc, naRef* args)
{
- FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
- nasal->setListener(argc, args);
- return naNil();
+ return nasalSys->setListener(c, argc, args);
+}
+
+// removelistener(int) extension function. Falls through to
+// FGNasalSys::removeListener(). See there for docs.
+static naRef f_removelistener(naContext c, naRef me, int argc, naRef* args)
+{
+ return nasalSys->removeListener(c, argc, args);
}
// Returns a ghost handle to the argument to the currently executing
// command
static naRef f_cmdarg(naContext c, naRef me, int argc, naRef* args)
{
- FGNasalSys* nasal = (FGNasalSys*)globals->get_subsystem("nasal");
- return nasal->cmdArgGhost();
+ return nasalSys->cmdArgGhost();
}
// Sets up a property interpolation. The first argument is either a
deltas[i] = naNumValue(naVec_get(curve, 2*i+1)).num;
}
- ((SGInterpolator*)globals->get_subsystem("interpolator"))
+ ((SGInterpolator*)globals->get_subsystem_mgr()
+ ->get_group(SGSubsystemMgr::INIT)->get_subsystem("interpolator"))
->interpolate(node, nPoints, values, deltas);
return naNil();
return result;
}
+// Parse XML file.
+// parsexml(<path> [, <start-tag> [, <end-tag> [, <data> [, <pi>]]]]);
+//
+// <path> ... absolute path of an XML file
+// <start-tag> ... callback function with two args: tag name, attribute hash
+// <end-tag> ... callback function with one arg: tag name
+// <data> ... callback function with one arg: data string
+// <pi> ... callback function with two args: target string, data string
+// (pi = "processing instruction")
+// All four callback functions are optional and default to nil.
+// The function returns nil on error, and the file name otherwise.
+static naRef f_parsexml(naContext c, naRef me, int argc, naRef* args)
+{
+ if(argc < 1 || !naIsString(args[0]))
+ naRuntimeError(c, "bad/missing argument to parsexml()");
+
+ const char* file = naStr_data(args[0]);
+ std::ifstream input(file);
+ NasalXMLVisitor visitor(c, argc, args);
+ try {
+ readXML(input, visitor);
+ } catch (const sg_exception& e) {
+ string msg = string("parsexml(): file '") + file + "' "
+ + e.getFormattedMessage();
+ naRuntimeError(c, msg.c_str());
+ return naNil();
+ }
+ return args[0];
+}
+
+// Return UNIX epoch time in seconds.
+static naRef f_systime(naContext c, naRef me, int argc, naRef* args)
+{
+#ifdef WIN32
+ FILETIME ft;
+ GetSystemTimeAsFileTime(&ft);
+ double t = (4294967296.0 * ft.dwHighDateTime + ft.dwLowDateTime);
+ // Converts from 100ns units in 1601 epoch to unix epoch in sec
+ return naNum((t * 1e-7) - 11644473600.0);
+#else
+ time_t t;
+ struct timeval td;
+ do { t = time(0); gettimeofday(&td, 0); } while(t != time(0));
+ return naNum(t + 1e-6 * td.tv_usec);
+#endif
+
+}
+
+// Convert a cartesian point to a geodetic lat/lon/altitude.
+static naRef f_carttogeod(naContext c, naRef me, int argc, naRef* args)
+{
+ const double RAD2DEG = 180.0 / SGD_PI;
+ double lat, lon, alt, xyz[3];
+ if(argc != 3) naRuntimeError(c, "carttogeod() expects 3 arguments");
+ for(int i=0; i<3; i++)
+ xyz[i] = naNumValue(args[i]).num;
+ sgCartToGeod(xyz, &lat, &lon, &alt);
+ lat *= RAD2DEG;
+ lon *= RAD2DEG;
+ naRef vec = naNewVector(c);
+ naVec_append(vec, naNum(lat));
+ naVec_append(vec, naNum(lon));
+ naVec_append(vec, naNum(alt));
+ return vec;
+}
+
+// Convert a geodetic lat/lon/altitude to a cartesian point.
+static naRef f_geodtocart(naContext c, naRef me, int argc, naRef* args)
+{
+ const double DEG2RAD = SGD_PI / 180.0;
+ if(argc != 3) naRuntimeError(c, "geodtocart() expects 3 arguments");
+ double lat = naNumValue(args[0]).num * DEG2RAD;
+ double lon = naNumValue(args[1]).num * DEG2RAD;
+ double alt = naNumValue(args[2]).num * DEG2RAD;
+ double xyz[3];
+ sgGeodToCart(lat, lon, alt, xyz);
+ naRef vec = naNewVector(c);
+ naVec_append(vec, naNum(xyz[0]));
+ naVec_append(vec, naNum(xyz[1]));
+ naVec_append(vec, naNum(xyz[2]));
+ return vec;
+}
+
+// For given geodetic point return array with elevation, and a material data
+// hash, or nil if there's no information available (tile not loaded). If
+// information about the material isn't available, then nil is returned instead
+// of the hash.
+static naRef f_geodinfo(naContext c, naRef me, int argc, naRef* args)
+{
+#define HASHSET(s,l,n) naHash_set(matdata, naStr_fromdata(naNewString(c),s,l),n)
+ if(argc != 2) naRuntimeError(c, "geodinfo() expects 2 arguments: lat, lon");
+ double lat = naNumValue(args[0]).num;
+ double lon = naNumValue(args[1]).num;
+ double elev;
+ const SGMaterial *mat;
+ if(!globals->get_scenery()->get_elevation_m(lat, lon, 10000.0, elev, &mat))
+ return naNil();
+ naRef vec = naNewVector(c);
+ naVec_append(vec, naNum(elev));
+ naRef matdata = naNil();
+ if(mat) {
+ matdata = naNewHash(c);
+ naRef names = naNewVector(c);
+ const vector<string> n = mat->get_names();
+ for(unsigned int i=0; i<n.size(); i++)
+ naVec_append(names, naStr_fromdata(naNewString(c),
+ const_cast<char*>(n[i].c_str()), n[i].size()));
+ HASHSET("names", 5, names);
+ HASHSET("solid", 5, naNum(mat->get_solid()));
+ HASHSET("friction_factor", 15, naNum(mat->get_friction_factor()));
+ HASHSET("rolling_friction", 16, naNum(mat->get_rolling_friction()));
+ HASHSET("load_resistance", 15, naNum(mat->get_load_resistance()));
+ HASHSET("bumpiness", 9, naNum(mat->get_bumpiness()));
+ HASHSET("light_coverage", 14, naNum(mat->get_light_coverage()));
+ }
+ naVec_append(vec, matdata);
+ return vec;
+#undef HASHSET
+}
+
// Table of extension functions. Terminate with zeros.
static struct { char* name; naCFunction func; } funcs[] = {
{ "getprop", f_getprop },
{ "_fgcommand", f_fgcommand },
{ "settimer", f_settimer },
{ "_setlistener", f_setlistener },
+ { "removelistener", f_removelistener },
{ "_cmdarg", f_cmdarg },
{ "_interpolate", f_interpolate },
{ "rand", f_rand },
{ "srand", f_srand },
{ "directory", f_directory },
+ { "parsexml", f_parsexml },
+ { "systime", f_systime },
+ { "carttogeod", f_carttogeod },
+ { "geodtocart", f_geodtocart },
+ { "geodinfo", f_geodinfo },
{ 0, 0 }
};
// sub-reference under the name "globals". This gives client-code
// write access to the namespace if someone wants to do something
// fancy.
- _globals = naStdLib(_context);
+ _globals = naInit_std(_context);
naSave(_context, _globals);
hashset(_globals, "globals", _globals);
- // Add in the math library under "math"
- hashset(_globals, "math", naMathLib(_context));
+ hashset(_globals, "math", naInit_math(_context));
+ hashset(_globals, "bits", naInit_bits(_context));
+ hashset(_globals, "io", naInit_io(_context));
+ hashset(_globals, "thread", naInit_thread(_context));
+ hashset(_globals, "utf8", naInit_utf8(_context));
// Add our custom extension functions:
for(i=0; funcs[i].name; i++)
if(file.extension() != "nas") continue;
loadModule(fullpath, file.base().c_str());
}
+ ulCloseDir(dir);
+
+ // set signal and remove node to avoid restoring at reinit
+ const char *s = "nasal-dir-initialized";
+ SGPropertyNode *signal = fgGetNode("/sim/signals", true);
+ signal->setBoolValue(s, true);
+ signal->removeChildren(s);
// Pull scripts out of the property tree, too
loadPropertyScripts();
}
+void FGNasalSys::update(double)
+{
+ if(_purgeListeners) {
+ _purgeListeners = false;
+ map<int, FGNasalListener *>::iterator it;
+ for(it = _listener.begin(); it != _listener.end();) {
+ FGNasalListener *nl = it->second;
+ if(nl->_dead) {
+ _listener.erase(it++);
+ delete nl;
+ } else {
+ ++it;
+ }
+ }
+ }
+}
+
// Loads the scripts found under /nasal in the global tree
void FGNasalSys::loadPropertyScripts()
{
loadModule(p, module);
}
*/
-
+
const char* src = n->getStringValue("script");
if(!n->hasChild("script")) src = 0; // Hrm...
if(src)
}
// Parse and run. Save the local variables namespace, as it will
-// become a sub-object of globals.
+// become a sub-object of globals. The optional "arg" argument can be
+// used to pass an associated property node to the module, which can then
+// be accessed via cmdarg(). (This is, for example, used by XML dialogs.)
void FGNasalSys::createModule(const char* moduleName, const char* fileName,
- const char* src, int len)
+ const char* src, int len, const SGPropertyNode* arg)
{
naRef code = parse(fileName, src, len);
if(naIsNil(code))
if(!naHash_get(_globals, modname, &locals))
locals = naNewHash(_context);
- naCall(_context, code, 0, 0, naNil(), locals);
- if(naGetError(_context)) {
- logError(_context);
- return;
- }
+ _cmdArg = (SGPropertyNode*)arg;
+
+ call(code, locals);
hashset(_globals, moduleName, locals);
}
+void FGNasalSys::deleteModule(const char* moduleName)
+{
+ naRef modname = naNewString(_context);
+ naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
+ naHash_delete(_globals, modname);
+}
+
naRef FGNasalSys::parse(const char* filename, const char* buf, int len)
{
int errLine = -1;
naRef code = parse(arg->getPath(true), nasal, strlen(nasal));
if(naIsNil(code)) return false;
+ // Commands can be run "in" a module. Make sure that module
+ // exists, and set it up as the local variables hash for the
+ // command.
naRef locals = naNil();
- if (moduleName[0]) {
+ if(moduleName[0]) {
naRef modname = naNewString(_context);
naStr_fromdata(modname, (char*)moduleName, strlen(moduleName));
- if(!naHash_get(_globals, modname, &locals))
+ if(!naHash_get(_globals, modname, &locals)) {
locals = naNewHash(_context);
+ naHash_set(_globals, modname, locals);
+ }
}
- // Cache the command argument for inspection via cmdarg(). For
+
+ // Cache this command's argument for inspection via cmdarg(). For
// performance reasons, we won't bother with it if the invoked
// code doesn't need it.
_cmdArg = (SGPropertyNode*)arg;
- // Call it!
- naRef result = naCall(_context, code, 0, 0, naNil(), locals);
- if(!naGetError(_context)) return true;
- logError(_context);
- return false;
+ call(code, locals);
+ return true;
}
// settimer(func, dt, simtime) extension function. The first argument
// "saved" somehow lest they be inadvertently cleaned. In this case,
// they are inserted into a globals.__gcsave hash and removed on
// expiration.
-void FGNasalSys::setTimer(int argc, naRef* args)
+void FGNasalSys::setTimer(naContext c, int argc, naRef* args)
{
// Extract the handler, delta, and simtime arguments:
naRef handler = argc > 0 ? args[0] : naNil();
- if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
+ if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler))) {
+ naRuntimeError(c, "settimer() with invalid function argument");
return;
+ }
naRef delta = argc > 1 ? args[1] : naNil();
- if(naIsNil(delta)) return;
-
+ if(naIsNil(delta)) {
+ naRuntimeError(c, "settimer() with invalid time argument");
+ return;
+ }
+
bool simtime = (argc > 2 && naTrue(args[2])) ? false : true;
// Generate and register a C++ timer handler
void FGNasalSys::handleTimer(NasalTimer* t)
{
- naCall(_context, t->handler, 0, 0, naNil(), naNil());
- if(naGetError(_context))
- logError(_context);
+ call(t->handler, naNil());
gcRelease(t->gcKey);
}
delete this;
}
-// setlistener(property, func) extension function. The first argument
+int FGNasalSys::_listenerId = 0;
+
+// setlistener(property, func, bool) extension function. The first argument
// is either a ghost (SGPropertyNode_ptr*) or a string (global property
-// path), the second is a Nasal function.
-void FGNasalSys::setListener(int argc, naRef* args)
+// path), the second is a Nasal function, the optional third one a bool.
+// If the bool is true, then the listener is executed initially. The
+// setlistener() function returns a unique id number, that can be used
+// as argument to the removelistener() function.
+naRef FGNasalSys::setListener(naContext c, int argc, naRef* args)
{
- SGPropertyNode* node;
+ SGPropertyNode_ptr node;
naRef prop = argc > 0 ? args[0] : naNil();
if(naIsString(prop)) node = fgGetNode(naStr_data(prop), true);
else if(naIsGhost(prop)) node = *(SGPropertyNode_ptr*)naGhost_ptr(prop);
- else return;
+ else {
+ naRuntimeError(c, "setlistener() with invalid property argument");
+ return naNil();
+ }
+
+ if(node->isTied())
+ SG_LOG(SG_NASAL, SG_DEBUG, "Attaching listener to tied property " <<
+ node->getPath());
naRef handler = argc > 1 ? args[1] : naNil();
- if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler)))
- return;
+ if(!(naIsCode(handler) || naIsCCode(handler) || naIsFunc(handler))) {
+ naRuntimeError(c, "setlistener() with invalid function argument");
+ return naNil();
+ }
bool initial = argc > 2 && naTrue(args[2]);
- node->addChangeListener(new FGNasalListener(handler, this, gcSave(handler)), initial);
+
+ FGNasalListener *nl = new FGNasalListener(node, handler, this,
+ gcSave(handler), _listenerId);
+ node->addChangeListener(nl, initial);
+
+ _listener[_listenerId] = nl;
+ return naNum(_listenerId++);
}
+// removelistener(int) extension function. The argument is the id of
+// a listener as returned by the setlistener() function.
+naRef FGNasalSys::removeListener(naContext c, int argc, naRef* args)
+{
+ naRef id = argc > 0 ? args[0] : naNil();
+ map<int, FGNasalListener *>::iterator it = _listener.find(int(id.num));
+
+ if(!naIsNum(id) || it == _listener.end() || it->second->_dead) {
+ naRuntimeError(c, "removelistener() with invalid listener id");
+ return naNil();
+ }
+
+ FGNasalListener *nl = it->second;
+ if(nl->_active) {
+ nl->_dead = true;
+ _purgeListeners = true;
+ return naNum(-1);
+ }
+
+ _listener.erase(it);
+ delete nl;
+ return naNum(_listener.size());
+}
+
+
+
+// FGNasalListener class.
+
+FGNasalListener::FGNasalListener(SGPropertyNode_ptr node, naRef handler,
+ FGNasalSys* nasal, int key, int id) :
+ _node(node),
+ _handler(handler),
+ _gcKey(key),
+ _id(id),
+ _nas(nasal),
+ _active(0),
+ _dead(false)
+{
+}
+
+FGNasalListener::~FGNasalListener()
+{
+ _node->removeChangeListener(this);
+ _nas->gcRelease(_gcKey);
+}
+
+void FGNasalListener::valueChanged(SGPropertyNode* node)
+{
+ // drop recursive listener calls
+ if(_active || _dead)
+ return;
+
+ SG_LOG(SG_NASAL, SG_DEBUG, "trigger listener #" << _id);
+ _active++;
+ _nas->_cmdArg = node;
+ _nas->call(_handler, naNil());
+ _active--;
+}
+
+
+
+
+// FGNasalModelData class. If sgLoad3DModel() is called with a pointer to
+// such a class, then it lets modelLoaded() run the <load> script, and the
+// destructor the <unload> script. The latter happens when the model branch
+// is removed from the scene graph.
+
+void FGNasalModelData::modelLoaded(const string& path, SGPropertyNode *prop,
+ osg::Node *)
+{
+ SGPropertyNode *n = prop->getNode("nasal"), *load;
+ if(!n)
+ return;
+
+ load = n->getNode("load");
+ _unload = n->getNode("unload");
+ if(!load && !_unload)
+ return;
+
+ _module = path;
+ const char *s = load ? load->getStringValue() : "";
+ nasalSys->createModule(_module.c_str(), _module.c_str(), s, strlen(s), _props);
+}
+
+FGNasalModelData::~FGNasalModelData()
+{
+ if(_module.empty())
+ return;
+
+ if(!nasalSys) {
+ SG_LOG(SG_NASAL, SG_ALERT, "Trying to run an <unload> script "
+ "without Nasal subsystem present.");
+ return;
+ }
+
+ if(_unload) {
+ const char *s = _unload->getStringValue();
+ nasalSys->createModule(_module.c_str(), _module.c_str(), s, strlen(s), _props);
+ }
+ nasalSys->deleteModule(_module.c_str());
+}
+
+
+
+// NasalXMLVisitor class: handles EasyXML visitor callback for parsexml()
+//
+NasalXMLVisitor::NasalXMLVisitor(naContext c, int argc, naRef* args) :
+ _c(naSubContext(c)),
+ _start_element(argc > 1 && naIsFunc(args[1]) ? args[1] : naNil()),
+ _end_element(argc > 2 && naIsFunc(args[2]) ? args[2] : naNil()),
+ _data(argc > 3 && naIsFunc(args[3]) ? args[3] : naNil()),
+ _pi(argc > 4 && naIsFunc(args[4]) ? args[4] : naNil())
+{
+}
+
+void NasalXMLVisitor::startElement(const char* tag, const XMLAttributes& a)
+{
+ if(naIsNil(_start_element)) return;
+ naRef attr = naNewHash(_c);
+ for(int i=0; i<a.size(); i++) {
+ naRef name = make_string(a.getName(i));
+ naRef value = make_string(a.getValue(i));
+ naHash_set(attr, name, value);
+ }
+ call(_start_element, 2, make_string(tag), attr);
+}
+
+void NasalXMLVisitor::endElement(const char* tag)
+{
+ if(!naIsNil(_end_element)) call(_end_element, 1, make_string(tag));
+}
+
+void NasalXMLVisitor::data(const char* str, int len)
+{
+ if(!naIsNil(_data)) call(_data, 1, make_string(str, len));
+}
+
+void NasalXMLVisitor::pi(const char* target, const char* data)
+{
+ if (!naIsNil(_pi)) call(_pi, 2, make_string(target), make_string(data));
+}
+
+void NasalXMLVisitor::call(naRef func, int num, naRef a, naRef b)
+{
+ _arg[0] = a;
+ _arg[1] = b;
+ naCall(_c, func, num, _arg, naNil(), naNil());
+ if(naGetError(_c))
+ naRethrowError(_c);
+}
+
+naRef NasalXMLVisitor::make_string(const char* s, int n)
+{
+ return naStr_fromdata(naNewString(_c), const_cast<char *>(s),
+ n < 0 ? strlen(s) : n);
+}
+
+