/// <summary>
/// Adds the package passed to the entry hierarchy, creating folders
/// as necessary.
/// </summary>
/// <param name="entry">The new entry.</param>
private void AddEntry(PackageEntry entry)
{
PackageEntry parent;
string path;
int pos, posEnd;
// Make sure that all of the folders up
// the hierarchy exist.
parent = root;
pos = 1;
while (true)
{
posEnd = entry.FullName.IndexOf('/', pos);
if (posEnd == -1)
{
break;
}
path = entry.FullName.Substring(0, posEnd);
parent = this[path];
if (parent != null && !parent.IsFolder)
{
throw new PackageException(MustBeFolder, path);
}
else if (parent == null)
{
parent = AddFolder(path);
}
pos = posEnd + 1;
}
entry.SetParent(parent);
parent.AddChild(entry);
entries.Add(entry.FullName.ToUpper(), entry);
}
/// <summary>
/// Scans the input stream, validating its structure and loading
/// the package entries.
/// </summary>
private void Load()
{
PackageHeader header;
byte[] hash;
packageIn.Position = 0;
header = new PackageHeader(packageIn);
cbHeader = (int)packageIn.Position;
// Compute a MD5 hash on the rest of then file and compare
// the result to what we read from the header.
hash = MD5Hasher.Compute(packageIn, packageIn.Length - cbHeader);
if (hash.Length != header.Hash.Length)
{
throw new PackageException(CorruptPackage);
}
for (int i = 0; i < hash.Length; i++)
{
if (hash[i] != header.Hash[i])
{
throw new PackageException(CorruptPackage);
}
}
// Read the package entry headers.
packageIn.Position = cbHeader;
while (true)
{
var entry = new PackageEntry(this, packageIn);
if (entry.IsEol)
{
break;
}
entries.Add(entry.FullName.ToUpper(), entry);
}
// Walk back through the entries and link each entry to
// its parent folder.
foreach (PackageEntry entry in entries.Values)
{
PackageEntry parent;
int pos;
if (entry == root)
{
continue;
}
pos = entry.FullName.LastIndexOf('/');
if (pos == -1)
{
throw new PackageException(CorruptPackage);
}
if (pos == 0)
{
parent = root;
}
else
{
parent = (PackageEntry)entries[entry.FullName.Substring(0, pos).ToUpper()];
if (parent == null)
{
throw new PackageException(CorruptPackage);
}
}
entry.SetParent(parent);
parent.AddChild(entry);
}
}