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Bugfix of problem reported by Mathias Fröhlich: Ground network trace()

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algorithm caused a program crash. Because there is always one waypoint more
than there are routes, the trace function should only pop_back the final route
entry at search depths of one or higher. I also added a lot of of additional
safeguarding code, due to the fact that the new trace algorithm was
apparently not as stable as I'd hoped it would be. ...
This commit is contained in:
durk 2006-08-16 09:58:26 +00:00
parent 0838ca6d35
commit e06e9ccd1e
2 changed files with 52 additions and 5 deletions
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55
src/Airports/groundnetwork.cxx
View file

@ -133,9 +133,10 @@ bool FGTaxiRoute::next(int *nde, int *rte)
// cerr << "true" << endl;
//else
// cerr << "false" << endl;
//if (nodes.size() != (routes.size()) +1)
// cerr << "ALERT: Misconfigured TaxiRoute : " << nodes.size() << " " << routes.size() << endl;
if (nodes.size() != (routes.size()) +1) {
SG_LOG(SG_GENERAL, SG_ALERT, "ALERT: Misconfigured TaxiRoute : " << nodes.size() << " " << routes.size());
exit(1);
}
if (currNode == nodes.end())
return false;
*nde = *(currNode);
@ -288,6 +289,12 @@ FGTaxiRoute FGGroundNetwork::findShortestRoute(int start, int end)
void FGGroundNetwork::trace(FGTaxiNode *currNode, int end, int depth, double distance)
{
// Just check some preconditions of the trace algorithm
if (nodesStack.size() != routesStack.size())
{
SG_LOG(SG_GENERAL, SG_ALERT, "size of nodesStack and routesStack is not equal. NodesStack :"
<< nodesStack.size() << ". RoutesStack : " << routesStack.size());
}
nodesStack.push_back(currNode->getIndex());
totalDistance += distance;
//cerr << "Starting trace " << depth << " total distance: " << totalDistance<< endl;
@ -299,6 +306,10 @@ void FGGroundNetwork::trace(FGTaxiNode *currNode, int end, int depth, double dis
{
//cerr << "Found route : " << totalDistance << "" << " " << *(nodesStack.end()-1) << endl;
routes.push_back(FGTaxiRoute(nodesStack,routesStack,totalDistance));
if (nodesStack.empty() || routesStack.empty())
{
printRoutingError(string("while finishing route"));
}
nodesStack.pop_back();
routesStack.pop_back();
if (!(foundRoute))
@ -327,6 +338,10 @@ void FGGroundNetwork::trace(FGTaxiNode *currNode, int end, int depth, double dis
i++;
}
if (i != nodesStack.end()-1) {
if (nodesStack.empty() || routesStack.empty())
{
printRoutingError(string("while returning from an already encountered node"));
}
nodesStack.pop_back();
routesStack.pop_back();
totalDistance -= distance;
@ -338,6 +353,10 @@ void FGGroundNetwork::trace(FGTaxiNode *currNode, int end, int depth, double dis
if ((totalDistance > maxDistance) && foundRoute)
{
//cerr << "Stopping rediculously long trace: " << totalDistance << endl;
if (nodesStack.empty() || routesStack.empty())
{
printRoutingError(string("while returning from finding a rediculously long route"));
}
nodesStack.pop_back();
routesStack.pop_back();
totalDistance -= distance;
@ -368,11 +387,37 @@ void FGGroundNetwork::trace(FGTaxiNode *currNode, int end, int depth, double dis
}
else
{
SG_LOG( SG_GENERAL, SG_DEBUG, "4" );
//SG_LOG( SG_GENERAL, SG_DEBUG, "4" );
}
if (nodesStack.empty())
{
printRoutingError(string("while finishing trace"));
}
nodesStack.pop_back();
routesStack.pop_back();
// Make sure not to dump the level-zero routesStack entry, because that was never created.
if (depth)
{
routesStack.pop_back();
//cerr << "leaving trace " << routesStack.size() << endl;
}
totalDistance -= distance;
return;
}
void FGGroundNetwork::printRoutingError(string mess)
{
SG_LOG(SG_GENERAL, SG_ALERT, "Error in ground network trace algorithm " << mess);
if (nodesStack.empty())
{
SG_LOG(SG_GENERAL, SG_ALERT, " nodesStack is empty. Dumping routesStack");
for (intVecIterator i = routesStack.begin() ; i != routesStack.end(); i++)
SG_LOG(SG_GENERAL, SG_ALERT, "Route " << (*i));
}
if (routesStack.empty())
{
SG_LOG(SG_GENERAL, SG_ALERT, " routesStack is empty. Dumping nodesStack");
for (intVecIterator i = nodesStack.begin() ; i != nodesStack.end(); i++)
SG_LOG(SG_GENERAL, SG_ALERT, "Node " << (*i));
}
//exit(1);
}

2
src/Airports/groundnetwork.hxx
View file

@ -161,6 +161,8 @@ private:
bool foundRoute;
double totalDistance, maxDistance;
void printRoutingError(string);
public:
FGGroundNetwork();