/// <summary>
/// Extracts an entry from the blob file and puts the bytes into memory.
/// </summary>
/// <param name="entry">The BlobEntry to extract to memory.</param>
/// <returns>The bytes of the entry in the blob file.</returns>
public byte[] ExtractBytes(BlobEntry entry)
{
FileStream input;
byte[] buffer;
if (entry == null)
{
throw new ArgumentNullException("entry");
}
#if DEBUG
Trace.WriteLine(_filename, "Filename");
#endif
buffer = new byte[entry.Size];
input = File.OpenRead(_filename);
input.Seek((long)entry.Offset, SeekOrigin.Begin);
input.Read(buffer, 0, buffer.Length);
return(buffer);
}
/// <summary>
/// Loads the blob file information.
/// </summary>
private void Load()
{
FileStream stream;
byte[] buffer;
BlobEntry entry;
int offset;
int end;
buffer = new byte[8];
stream = File.OpenRead(_filename);
stream.Read(buffer, 0, 8);
_version = BitConverter.ToInt32(buffer, 0);
_count = BitConverter.ToInt32(buffer, 4);
offset = 0;
if (_version == 1)
{
buffer = new byte[22 * _count];
stream.Read(buffer, 0, buffer.Length);
stream.Close();
_entries = new List <BlobEntry>(_count);
for (int i = 0; i < _count; i++)
{
entry = new BlobEntry();
entry.Filename = ASCIIEncoding.ASCII.GetString(buffer, offset, 14); offset += 14;
end = entry.Filename.IndexOf('\0');
if (end > 0)
{
entry.Filename = entry.Filename.Substring(0, end);
}
entry.Offset = BitConverter.ToInt32(buffer, offset); offset += 4;
entry.Size = BitConverter.ToInt32(buffer, offset); offset += 4;
_entries.Add(entry);
}
}
else if (_version == 2)
{
buffer = new byte[40 * _count];
stream.Read(buffer, 0, buffer.Length);
stream.Close();
_entries = new List <BlobEntry>(_count);
for (int i = 0; i < _count; i++)
{
entry = new BlobEntry();
entry.Filename = ASCIIEncoding.ASCII.GetString(buffer, offset, 32); offset += 32;
end = entry.Filename.IndexOf('\0');
if (end > 0)
{
entry.Filename = entry.Filename.Substring(0, end);
}
entry.Offset = BitConverter.ToInt32(buffer, offset); offset += 4;
entry.Size = BitConverter.ToInt32(buffer, offset); offset += 4;
_entries.Add(entry);
}
}
else
{
throw new Exception("Unknown file version: " + _version);
}
}
public void Add(string filename)
{
FileStream originalStream, tempStream;
BinaryWriter writer;
int size;
int headerLength;
int offset;
string tempname;
byte[] buffer, data;
BlobEntry item;
FileInfo info;
info = new FileInfo(filename);
item = new BlobEntry();
item.Filename = Path.GetFileName(filename);
item.Size = (int)info.Length;
_count++;
tempname = Path.GetTempFileName();
originalStream = new FileStream(_filename, FileMode.Open, FileAccess.Read, FileShare.Read);
tempStream = new FileStream(tempname, FileMode.Open, FileAccess.Write, FileShare.None);
writer = new BinaryWriter(tempStream);
writer.Write(_version);
writer.Write(_count);
if (_version == 1)
{
size = 14;
}
else
{
size = 32;
}
headerLength = size * _count;
// Write the header
offset = headerLength;
for (int i = 0; i < _entries.Count; i++)
{
// Make sure the string is the correct length
data = ASCIIEncoding.ASCII.GetBytes(_entries[i].Filename);
buffer = new byte[size];
Array.Clear(buffer, 0, buffer.Length);
Array.Copy(data, 0, buffer, 0, data.Length);
writer.Write(buffer); // filename
_entries[i].Offset = offset;
writer.Write(_entries[i].Offset); // offset
offset += _entries[i].Size;
writer.Write(_entries[i].Size); // file size
}
// Make sure the string is the correct length
data = ASCIIEncoding.ASCII.GetBytes(item.Filename);
buffer = new byte[size];
Array.Clear(buffer, 0, buffer.Length);
Array.Copy(data, 0, buffer, 0, data.Length);
writer.Write(buffer); // filename
item.Offset = offset;
writer.Write(item.Offset); // offset
offset += item.Size;
writer.Write(item.Size); // file size
// Write the file data
foreach (BlobEntry entry in _entries)
{
originalStream.Seek((long)entry.Offset, SeekOrigin.Begin);
buffer = new byte[entry.Size];
originalStream.Read(buffer, 0, buffer.Length);
writer.Write(buffer);
}
buffer = File.ReadAllBytes(filename);
writer.Write(buffer);
originalStream.Close();
tempStream.Close();
_entries.Add(item);
File.Delete(_filename);
File.Move(tempname, _filename);
}
