3 * Started Fall 2000 by David Megginson, david@megginson.com
4 * This code is released into the Public Domain.
6 * See props.html for documentation [replace with URL when available].
12 # include <simgear_config.h>
15 #include <simgear/compiler.h>
17 #include <stdlib.h> // atof() atoi()
19 #include <simgear/sg_inlines.h>
20 #include <simgear/debug/logstream.hxx>
21 #include <simgear/misc/sg_path.hxx>
22 #include <simgear/xml/easyxml.hxx>
25 #include "props_io.hxx"
33 SG_USING_STD(istream);
34 SG_USING_STD(ifstream);
35 SG_USING_STD(ostream);
36 SG_USING_STD(ofstream);
41 #define DEFAULT_MODE (SGPropertyNode::READ|SGPropertyNode::WRITE)
45 ////////////////////////////////////////////////////////////////////////
46 // Property list visitor, for XML parsing.
47 ////////////////////////////////////////////////////////////////////////
49 class PropsVisitor : public XMLVisitor
53 PropsVisitor (SGPropertyNode * root, const string &base, int default_mode = 0)
54 : _default_mode(default_mode), _root(root), _level(0), _base(base), _hasException(false) {}
56 virtual ~PropsVisitor () {}
60 void startElement (const char * name, const XMLAttributes &atts);
61 void endElement (const char * name);
62 void data (const char * s, int length);
63 void warning (const char * message, int line, int column);
65 bool hasException () const { return _hasException; }
66 sg_io_exception &getException () { return _exception; }
67 void setException (const sg_io_exception &exception) {
68 _exception = exception;
76 State () : node(0), type(""), mode(DEFAULT_MODE) {}
77 State (SGPropertyNode * _node, const char * _type, int _mode)
78 : node(_node), type(_type), mode(_mode) {}
79 SGPropertyNode * node;
82 map<string,int> counters;
85 State &state () { return _state_stack[_state_stack.size() - 1]; }
87 void push_state (SGPropertyNode * node, const char * type, int mode) {
89 _state_stack.push_back(State(node, "unspecified", mode));
91 _state_stack.push_back(State(node, type, mode));
97 _state_stack.pop_back();
103 SGPropertyNode * _root;
105 vector<State> _state_stack;
107 sg_io_exception _exception;
112 PropsVisitor::startXML ()
115 _state_stack.resize(0);
119 PropsVisitor::endXML ()
122 _state_stack.resize(0);
127 * Check a yes/no flag, with default.
130 checkFlag (const char * flag, bool defaultState = true)
134 else if (!strcmp(flag, "y"))
136 else if (!strcmp(flag, "n"))
139 string message = "Unrecognized flag value '";
142 // FIXME: add location info
143 throw sg_io_exception(message, "SimGear Property Reader");
148 PropsVisitor::startElement (const char * name, const XMLAttributes &atts)
153 if (strcmp(name, "PropertyList")) {
154 string message = "Root element name is ";
156 message += "; expected PropertyList";
157 throw sg_io_exception(message, "SimGear Property Reader");
160 // Check for an include.
161 attval = atts.getValue("include");
163 SGPath path(SGPath(_base).dir());
166 readProperties(path.str(), _root);
167 } catch (sg_io_exception &e) {
172 push_state(_root, "", DEFAULT_MODE);
178 attval = atts.getValue("n");
181 index = atoi(attval);
182 st.counters[name] = SG_MAX2(st.counters[name], index+1);
184 index = st.counters[name];
188 // Got the index, so grab the node.
189 SGPropertyNode * node = st.node->getChild(name, index, true);
191 // Get the access-mode attributes,
192 // but don't set yet (in case they
193 // prevent us from recording the value).
194 int mode = _default_mode;
196 attval = atts.getValue("read");
197 if (checkFlag(attval, true))
198 mode |= SGPropertyNode::READ;
199 attval = atts.getValue("write");
200 if (checkFlag(attval, true))
201 mode |= SGPropertyNode::WRITE;
202 attval = atts.getValue("archive");
203 if (checkFlag(attval, false))
204 mode |= SGPropertyNode::ARCHIVE;
205 attval = atts.getValue("trace-read");
206 if (checkFlag(attval, false))
207 mode |= SGPropertyNode::TRACE_READ;
208 attval = atts.getValue("trace-write");
209 if (checkFlag(attval, false))
210 mode |= SGPropertyNode::TRACE_WRITE;
211 attval = atts.getValue("userarchive");
212 if (checkFlag(attval, false))
213 mode |= SGPropertyNode::USERARCHIVE;
215 // Check for an alias.
216 attval = atts.getValue("alias");
218 if (!node->alias(attval))
219 SG_LOG(SG_INPUT, SG_ALERT, "Failed to set alias to " << attval);
222 // Check for an include.
223 attval = atts.getValue("include");
225 SGPath path(SGPath(_base).dir());
228 readProperties(path.str(), node);
229 } catch (sg_io_exception &e) {
233 const char *omit = atts.getValue("omit-node");
234 if (omit && !strcmp(omit, "y")) {
235 int nChildren = node->nChildren();
236 for (int i = 0; i < nChildren; i++) {
237 SGPropertyNode *src = node->getChild(i);
238 const char *name = src->getName();
239 int index = st.counters[name];
241 SGPropertyNode *dst = st.node->getChild(name, index, true);
242 copyProperties(src, dst);
244 st.node->removeChild(node->getName(), node->getIndex(), false);
249 const char *type = atts.getValue("type");
252 push_state(node, type, mode);
257 PropsVisitor::endElement (const char * name)
262 // If there are no children and it's
263 // not an alias, then it's a leaf value.
264 if (st.node->nChildren() == 0 && !st.node->isAlias()) {
265 if (st.type == "bool") {
266 if (_data == "true" || atoi(_data.c_str()) != 0)
267 ret = st.node->setBoolValue(true);
269 ret = st.node->setBoolValue(false);
270 } else if (st.type == "int") {
271 ret = st.node->setIntValue(atoi(_data.c_str()));
272 } else if (st.type == "long") {
273 ret = st.node->setLongValue(strtol(_data.c_str(), 0, 0));
274 } else if (st.type == "float") {
275 ret = st.node->setFloatValue(atof(_data.c_str()));
276 } else if (st.type == "double") {
277 ret = st.node->setDoubleValue(strtod(_data.c_str(), 0));
278 } else if (st.type == "string") {
279 ret = st.node->setStringValue(_data.c_str());
280 } else if (st.type == "unspecified") {
281 ret = st.node->setUnspecifiedValue(_data.c_str());
282 } else if (_level == 1) {
283 ret = true; // empty <PropertyList>
285 string message = "Unrecognized data type '";
288 // FIXME: add location information
289 throw sg_io_exception(message, "SimGear Property Reader");
292 SG_LOG(SG_INPUT, SG_ALERT, "readProperties: Failed to set "
293 << st.node->getPath() << " to value \""
294 << _data << "\" with type " << st.type);
297 // Set the access-mode attributes now,
298 // once the value has already been
300 st.node->setAttributes(st.mode);
306 PropsVisitor::data (const char * s, int length)
308 if (state().node->nChildren() == 0)
309 _data.append(string(s, length));
313 PropsVisitor::warning (const char * message, int line, int column)
315 SG_LOG(SG_INPUT, SG_ALERT, "readProperties: warning: "
316 << message << " at line " << line << ", column " << column);
321 ////////////////////////////////////////////////////////////////////////
322 // Property list reader.
323 ////////////////////////////////////////////////////////////////////////
327 * Read properties from an input stream.
329 * @param input The input stream containing an XML property file.
330 * @param start_node The root node for reading properties.
331 * @param base A base path for resolving external include references.
332 * @return true if the read succeeded, false otherwise.
335 readProperties (istream &input, SGPropertyNode * start_node,
336 const string &base, int default_mode)
338 PropsVisitor visitor(start_node, base, default_mode);
339 readXML(input, visitor, base);
340 if (visitor.hasException())
341 throw visitor.getException();
346 * Read properties from a file.
348 * @param file A string containing the file path.
349 * @param start_node The root node for reading properties.
350 * @return true if the read succeeded, false otherwise.
353 readProperties (const string &file, SGPropertyNode * start_node,
356 PropsVisitor visitor(start_node, file, default_mode);
357 readXML(file, visitor);
358 if (visitor.hasException())
359 throw visitor.getException();
364 * Read properties from an in-memory buffer.
366 * @param buf A character buffer containing the xml data.
367 * @param size The size/length of the buffer in bytes
368 * @param start_node The root node for reading properties.
369 * @return true if the read succeeded, false otherwise.
371 void readProperties (const char *buf, const int size,
372 SGPropertyNode * start_node, int default_mode)
374 PropsVisitor visitor(start_node, "", default_mode);
375 readXML(buf, size, visitor);
376 if (visitor.hasException())
377 throw visitor.getException();
381 ////////////////////////////////////////////////////////////////////////
382 // Property list writer.
383 ////////////////////////////////////////////////////////////////////////
385 #define INDENT_STEP 2
388 * Return the type name.
391 getTypeName (SGPropertyNode::Type type)
394 case SGPropertyNode::UNSPECIFIED:
395 return "unspecified";
396 case SGPropertyNode::BOOL:
398 case SGPropertyNode::INT:
400 case SGPropertyNode::LONG:
402 case SGPropertyNode::FLOAT:
404 case SGPropertyNode::DOUBLE:
406 case SGPropertyNode::STRING:
408 case SGPropertyNode::ALIAS:
409 case SGPropertyNode::NONE:
410 return "unspecified";
413 // keep the compiler from squawking
414 return "unspecified";
419 * Escape characters for output.
422 writeData (ostream &output, const string &data)
424 for (int i = 0; i < (int)data.size(); i++) {
443 doIndent (ostream &output, int indent)
445 while (indent-- > 0) {
452 writeAtts (ostream &output, const SGPropertyNode * node, bool forceindex)
454 int index = node->getIndex();
456 if (index != 0 || forceindex)
457 output << " n=\"" << index << '"';
460 if (!node->getAttribute(SGPropertyNode::READ))
461 output << " read=\"n\"";
463 if (!node->getAttribute(SGPropertyNode::WRITE))
464 output << " write=\"n\"";
466 if (node->getAttribute(SGPropertyNode::ARCHIVE))
467 output << " archive=\"y\"";
474 * Test whether a node is archivable or has archivable descendants.
477 isArchivable (const SGPropertyNode * node, SGPropertyNode::Attribute archive_flag)
479 // FIXME: it's inefficient to do this all the time
480 if (node->getAttribute(archive_flag))
483 int nChildren = node->nChildren();
484 for (int i = 0; i < nChildren; i++)
485 if (isArchivable(node->getChild(i), archive_flag))
493 writeNode (ostream &output, const SGPropertyNode * node,
494 bool write_all, int indent, SGPropertyNode::Attribute archive_flag)
496 // Don't write the node or any of
497 // its descendants unless it is
498 // allowed to be archived.
499 if (!write_all && !isArchivable(node, archive_flag))
500 return true; // Everything's OK, but we won't write.
502 const string name = node->getName();
503 int nChildren = node->nChildren();
504 bool node_has_value = false;
506 // If there is a literal value,
508 if (node->hasValue() && (write_all || node->getAttribute(archive_flag))) {
509 doIndent(output, indent);
510 output << '<' << name;
511 writeAtts(output, node, nChildren != 0);
512 if (node->isAlias() && node->getAliasTarget() != 0) {
513 output << " alias=\"" << node->getAliasTarget()->getPath()
516 if (node->getType() != SGPropertyNode::UNSPECIFIED)
517 output << " type=\"" << getTypeName(node->getType()) << '"';
519 writeData(output, node->getStringValue());
520 output << "</" << name << '>' << endl;
522 node_has_value = true;
525 // If there are children, write them next.
527 doIndent(output, indent);
528 output << '<' << name;
529 writeAtts(output, node, node_has_value);
530 output << '>' << endl;
531 for (int i = 0; i < nChildren; i++)
532 writeNode(output, node->getChild(i), write_all, indent + INDENT_STEP, archive_flag);
533 doIndent(output, indent);
534 output << "</" << name << '>' << endl;
542 writeProperties (ostream &output, const SGPropertyNode * start_node,
543 bool write_all, SGPropertyNode::Attribute archive_flag)
545 int nChildren = start_node->nChildren();
547 output << "<?xml version=\"1.0\"?>" << endl << endl;
548 output << "<PropertyList>" << endl;
550 for (int i = 0; i < nChildren; i++) {
551 writeNode(output, start_node->getChild(i), write_all, INDENT_STEP, archive_flag);
554 output << "</PropertyList>" << endl;
559 writeProperties (const string &file, const SGPropertyNode * start_node,
560 bool write_all, SGPropertyNode::Attribute archive_flag)
562 SGPath path(file.c_str());
563 path.create_dir(0777);
565 ofstream output(file.c_str());
567 writeProperties(output, start_node, write_all, archive_flag);
569 throw sg_io_exception("Cannot open file", sg_location(file));
575 ////////////////////////////////////////////////////////////////////////
576 // Copy properties from one tree to another.
577 ////////////////////////////////////////////////////////////////////////
581 * Copy one property tree to another.
583 * @param in The source property tree.
584 * @param out The destination property tree.
585 * @return true if all properties were copied, false if some failed
586 * (for example, if the property's value is tied read-only).
589 copyProperties (const SGPropertyNode *in, SGPropertyNode *out)
593 // First, copy the actual value,
595 if (in->hasValue()) {
596 switch (in->getType()) {
597 case SGPropertyNode::BOOL:
598 if (!out->setBoolValue(in->getBoolValue()))
601 case SGPropertyNode::INT:
602 if (!out->setIntValue(in->getIntValue()))
605 case SGPropertyNode::LONG:
606 if (!out->setLongValue(in->getLongValue()))
609 case SGPropertyNode::FLOAT:
610 if (!out->setFloatValue(in->getFloatValue()))
613 case SGPropertyNode::DOUBLE:
614 if (!out->setDoubleValue(in->getDoubleValue()))
617 case SGPropertyNode::STRING:
618 if (!out->setStringValue(in->getStringValue()))
621 case SGPropertyNode::UNSPECIFIED:
622 if (!out->setUnspecifiedValue(in->getStringValue()))
628 string message = "Unknown internal SGPropertyNode type";
629 message += in->getType();
630 throw sg_error(message, "SimGear Property Reader");
634 // copy the attributes.
635 out->setAttributes( in->getAttributes() );
637 // Next, copy the children.
638 int nChildren = in->nChildren();
639 for (int i = 0; i < nChildren; i++) {
640 const SGPropertyNode * in_child = in->getChild(i);
641 SGPropertyNode * out_child = out->getChild(in_child->getName(),
642 in_child->getIndex(),
644 if (!copyProperties(in_child, out_child))
651 // end of props_io.cxx