internal void ApplyDelta(Deltified delta)
{
int deltaPtr = 0;
// Length of the base object (a variable length int).
//
int baseLen = 0;
int c, shift = 0;
do
{
c = delta.Delta[deltaPtr++];
baseLen |= (c & 0x7f) << shift;
shift += 7;
} while ((c & 0x80) != 0);
if (Content.Length != baseLen)
{
throw new ArgumentException("baseData length incorrect");
}
// Length of the resulting object (a variable length int).
//
int resLen = 0;
shift = 0;
do
{
c = delta.Delta[deltaPtr++] & 0xff;
resLen |= (c & 0x7f) << shift;
shift += 7;
} while ((c & 0x80) != 0);
byte[] result = new byte[resLen];
int resultPtr = 0;
while (deltaPtr < delta.Delta.Length)
{
int cmd = delta.Delta[deltaPtr++] & 0xff;
if ((cmd & 0x80) != 0)
{
// Determine the segment of the base which should
// be copied into the output. The segment is given
// as an offset and a length.
//
int copyOffset = 0;
if ((cmd & 0x01) != 0)
{
copyOffset = delta.Delta[deltaPtr++] & 0xff;
}
if ((cmd & 0x02) != 0)
{
copyOffset |= (delta.Delta[deltaPtr++] & 0xff) << 8;
}
if ((cmd & 0x04) != 0)
{
copyOffset |= (delta.Delta[deltaPtr++] & 0xff) << 16;
}
if ((cmd & 0x08) != 0)
{
copyOffset |= (delta.Delta[deltaPtr++] & 0xff) << 24;
}
int copySize = 0;
if ((cmd & 0x10) != 0)
{
copySize = delta.Delta[deltaPtr++] & 0xff;
}
if ((cmd & 0x20) != 0)
{
copySize |= (delta.Delta[deltaPtr++] & 0xff) << 8;
}
if ((cmd & 0x40) != 0)
{
copySize |= (delta.Delta[deltaPtr++] & 0xff) << 16;
}
if (copySize == 0)
{
copySize = 0x10000;
}
Array.Copy(Content, copyOffset, result, resultPtr, copySize);
resultPtr += copySize;
}
else if (cmd != 0)
{
// Anything else the data is literal within the delta
// itself.
//
Array.Copy(delta.Delta, deltaPtr, result, resultPtr, cmd);
deltaPtr += cmd;
resultPtr += cmd;
}
else
{
// cmd == 0 has been reserved for future encoding but
// for now its not acceptable.
//
throw new ArgumentException("unsupported command 0");
}
}
Content = result;
}
internal void ApplyDelta(Deltified delta)
{
Delta = ApplyDelta(delta.Delta);
}
internal void ApplyDelta(Deltified delta)
{
Content = delta.ApplyDelta(Content);
}