public static IEnt Find(IDir parent, String rel, bool onlyDir) {
if (rel.Length == 0 || rel == ".") {
return parent;
}
if (rel.StartsWith("/")) {
return Find(GetRoot(parent), rel.Substring(1), onlyDir);
}
if (rel == "..") {
return parent.ParentDir;
}
if (rel.StartsWith("./")) {
return Find(parent, rel.Substring(2), onlyDir);
}
if (rel.StartsWith("../")) {
return Find(parent.ParentDir, rel.Substring(3), onlyDir);
}
int p = rel.IndexOf('/');
String part = (p < 0) ? rel : rel.Substring(0, p);
foreach (IEnt o in parent.GetEnts()) {
if (o.Name.Equals(part)) {
if (o is IDir) {
if (p < 0)
return o;
return Find(o as IDir, rel.Substring(p + 1), onlyDir);
}
else if (onlyDir) {
throw new EntNotFoundException("We knew \"" + rel + "\" is a file.");
}
else {
if (p < 0)
return o;
throw new EntNotFoundException("We knew \"" + rel + "\" is a file.");
}
}
}
throw new EntNotFoundException("We don't find \"" + rel + "\".");
}