/// <summary>
/// Returns the directory information associated with a main directory entry at a given index.
/// </summary>
/// <param name="dirIndex">Index of the main directory entry.</param>
/// <returns></returns>
/// <exception cref="FileNotFoundException">Thrown if the file does not exist in the filesystem.</exception>
internal DragonDosDirectoryItem GetDirectoryItem(int dirIndex)
{
ReadDirectoryTrack();
var extents = new List <DragonDosDirectoryEntry.Extent>();
var direntries = new List <int>();
var item = new DragonDosDirectoryItem();
var dirent = GetDirectoryEntry(dirIndex);
item.Filename = dirent.Filename;
item.IsProtected = dirent.IsProtected;
direntries.Add(dirIndex);
foreach (var extent in dirent.Extents)
{
extents.Add(extent);
}
while (dirent.IsExtended)
{
dirIndex = dirent.NextEntry;
dirent = GetDirectoryEntry(dirIndex);
direntries.Add(dirIndex);
foreach (var extent in dirent.Extents)
{
extents.Add(extent);
}
}
item.Extents = extents.ToArray();
item.DirEntries = direntries.ToArray();
item.LastSectorSize = dirent.LastSectorSize;
return(item);
}
/// <summary>
/// Returns the payload data for a given file.
/// </summary>
/// <param name="item"></param>
/// <returns></returns>
internal byte[] GetFileData(DragonDosDirectoryItem item)
{
int size = item.Size;
byte[] data = new byte[size];
int offset = 0;
foreach (var extent in item.Extents)
{
int lsn = extent.Lsn;
int len = extent.Length;
while (len-- > 0)
{
var sector = ReadSector(lsn++);
Array.Copy(sector, 0, data, offset, Math.Min(size, SectorSize));
size -= SectorSize;
offset += SectorSize;
}
}
return(data);
}
/// <summary>
/// Returns the payload data for a given file.
/// </summary>
/// <param name="item"></param>
/// <returns></returns>
internal byte[] GetFileData(DragonDosDirectoryItem item)
{
int size = item.Size;
byte[] data = new byte[size];
int offset = 0;
foreach (var extent in item.Extents)
{
int lsn = extent.Lsn;
int len = extent.Length;
while (len-- > 0)
{
var sector = ReadSector(lsn++);
Array.Copy(sector, 0, data, offset, Math.Min(size, SectorSize));
size -= SectorSize;
offset += SectorSize;
}
}
return data;
}
/// <summary>
/// Returns the directory information associated with a main directory entry at a given index.
/// </summary>
/// <param name="dirIndex">Index of the main directory entry.</param>
/// <returns></returns>
/// <exception cref="FileNotFoundException">Thrown if the file does not exist in the filesystem.</exception>
internal DragonDosDirectoryItem GetDirectoryItem(int dirIndex)
{
ReadDirectoryTrack();
var extents = new List<DragonDosDirectoryEntry.Extent>();
var direntries = new List<int>();
var item = new DragonDosDirectoryItem();
var dirent = GetDirectoryEntry(dirIndex);
item.Filename = dirent.Filename;
item.IsProtected = dirent.IsProtected;
direntries.Add(dirIndex);
foreach (var extent in dirent.Extents)
{
extents.Add(extent);
}
while (dirent.IsExtended)
{
dirIndex = dirent.NextEntry;
dirent = GetDirectoryEntry(dirIndex);
direntries.Add(dirIndex);
foreach (var extent in dirent.Extents)
{
extents.Add(extent);
}
}
item.Extents = extents.ToArray();
item.DirEntries = direntries.ToArray();
item.LastSectorSize = dirent.LastSectorSize;
return item;
}
