static void CreateInternal(byte[] oldData, byte[] newData, Stream output)
{
// check arguments
if (oldData == null)
{
throw new ArgumentNullException("oldData");
}
if (newData == null)
{
throw new ArgumentNullException("newData");
}
if (output == null)
{
throw new ArgumentNullException("output");
}
if (!output.CanSeek)
{
throw new ArgumentException("Output stream must be seekable.", "output");
}
if (!output.CanWrite)
{
throw new ArgumentException("Output stream must be writable.", "output");
}
/* Header is
* 0 8 "BSDIFF40"
* 8 8 length of bzip2ed ctrl block
* 16 8 length of bzip2ed diff block
* 24 8 length of new file */
/* File is
* 0 32 Header
* 32 ?? Bzip2ed ctrl block
* ?? ?? Bzip2ed diff block
* ?? ?? Bzip2ed extra block */
byte[] header = new byte[c_headerSize];
WriteInt64(c_fileSignature, header, 0); // "BSDIFF40"
WriteInt64(0, header, 8);
WriteInt64(0, header, 16);
WriteInt64(newData.Length, header, 24);
long startPosition = output.Position;
output.Write(header, 0, header.Length);
int[] I = SuffixSort(oldData);
byte[] db = new byte[newData.Length];
byte[] eb = new byte[newData.Length];
int dblen = 0;
int eblen = 0;
using (WrappingStream wrappingStream = new WrappingStream(output, Ownership.None))
using (var bz2Stream = new BZip2Stream(wrappingStream, CompressionMode.Compress))
{
// compute the differences, writing ctrl as we go
int scan = 0;
int pos = 0;
int len = 0;
int lastscan = 0;
int lastpos = 0;
int lastoffset = 0;
while (scan < newData.Length)
{
int oldscore = 0;
for (int scsc = scan += len; scan < newData.Length; scan++)
{
len = Search(I, oldData, newData, scan, 0, oldData.Length, out pos);
for (; scsc < scan + len; scsc++)
{
if ((scsc + lastoffset < oldData.Length) && (oldData[scsc + lastoffset] == newData[scsc]))
{
oldscore++;
}
}
if ((len == oldscore && len != 0) || (len > oldscore + 8))
{
break;
}
if ((scan + lastoffset < oldData.Length) && (oldData[scan + lastoffset] == newData[scan]))
{
oldscore--;
}
}
if (len != oldscore || scan == newData.Length)
{
int s = 0;
int sf = 0;
int lenf = 0;
for (int i = 0; (lastscan + i < scan) && (lastpos + i < oldData.Length);)
{
if (oldData[lastpos + i] == newData[lastscan + i])
{
s++;
}
i++;
if (s * 2 - i > sf * 2 - lenf)
{
sf = s;
lenf = i;
}
}
int lenb = 0;
if (scan < newData.Length)
{
s = 0;
int sb = 0;
for (int i = 1; (scan >= lastscan + i) && (pos >= i); i++)
{
if (oldData[pos - i] == newData[scan - i])
{
s++;
}
if (s * 2 - i > sb * 2 - lenb)
{
sb = s;
lenb = i;
}
}
}
if (lastscan + lenf > scan - lenb)
{
int overlap = (lastscan + lenf) - (scan - lenb);
s = 0;
int ss = 0;
int lens = 0;
for (int i = 0; i < overlap; i++)
{
if (newData[lastscan + lenf - overlap + i] == oldData[lastpos + lenf - overlap + i])
{
s++;
}
if (newData[scan - lenb + i] == oldData[pos - lenb + i])
{
s--;
}
if (s > ss)
{
ss = s;
lens = i + 1;
}
}
lenf += lens - overlap;
lenb -= lens;
}
for (int i = 0; i < lenf; i++)
{
db[dblen + i] = (byte)(newData[lastscan + i] - oldData[lastpos + i]);
}
for (int i = 0; i < (scan - lenb) - (lastscan + lenf); i++)
{
eb[eblen + i] = newData[lastscan + lenf + i];
}
dblen += lenf;
eblen += (scan - lenb) - (lastscan + lenf);
byte[] buf = new byte[8];
WriteInt64(lenf, buf, 0);
bz2Stream.Write(buf, 0, 8);
WriteInt64((scan - lenb) - (lastscan + lenf), buf, 0);
bz2Stream.Write(buf, 0, 8);
WriteInt64((pos - lenb) - (lastpos + lenf), buf, 0);
bz2Stream.Write(buf, 0, 8);
lastscan = scan - lenb;
lastpos = pos - lenb;
lastoffset = pos - scan;
}
}
}
// compute size of compressed ctrl data
long controlEndPosition = output.Position;
WriteInt64(controlEndPosition - startPosition - c_headerSize, header, 8);
// write compressed diff data
using (WrappingStream wrappingStream = new WrappingStream(output, Ownership.None))
using (var bz2Stream = new BZip2Stream(wrappingStream, CompressionMode.Compress))
{
bz2Stream.Write(db, 0, dblen);
}
// compute size of compressed diff data
long diffEndPosition = output.Position;
WriteInt64(diffEndPosition - controlEndPosition, header, 16);
// write compressed extra data, if any
if (eblen > 0)
{
using (WrappingStream wrappingStream = new WrappingStream(output, Ownership.None))
using (var bz2Stream = new BZip2Stream(wrappingStream, CompressionMode.Compress))
{
bz2Stream.Write(eb, 0, eblen);
}
}
// seek to the beginning, write the header, then seek back to end
long endPosition = output.Position;
output.Position = startPosition;
output.Write(header, 0, header.Length);
output.Position = endPosition;
}
private static void CreateInternal(byte[] oldData, byte[] newData, Stream output)
{
long num4;
if (oldData == null)
{
throw new ArgumentNullException("oldData");
}
if (newData == null)
{
throw new ArgumentNullException("newData");
}
if (output == null)
{
throw new ArgumentNullException("output");
}
if (!output.CanSeek)
{
throw new ArgumentException("Output stream must be seekable.", "output");
}
if (!output.CanWrite)
{
throw new ArgumentException("Output stream must be writable.", "output");
}
byte[] buf = new byte[0x20];
WriteInt64(0x3034464649445342L, buf, 0);
WriteInt64(0L, buf, 8);
WriteInt64(0L, buf, 0x10);
WriteInt64((long)newData.Length, buf, 0x18);
long position = output.Position;
output.Write(buf, 0, buf.Length);
int[] i = SuffixSort(oldData);
byte[] buffer = new byte[newData.Length];
byte[] buffer3 = new byte[newData.Length];
int count = 0;
int num3 = 0;
using (WrappingStream stream = new WrappingStream(output, Ownership.None))
{
using (BZip2OutputStream stream2 = new BZip2OutputStream(stream))
{
int num12;
int newOffset = 0;
int pos = 0;
int num8 = 0;
int num9 = 0;
int num10 = 0;
int num11 = 0;
goto TR_0059;
TR_0049:
if ((num8 != num12) || (newOffset == newData.Length))
{
int num14 = 0;
int num15 = 0;
int num16 = 0;
int num18 = 0;
while (true)
{
if (((num9 + num18) >= newOffset) || ((num10 + num18) >= oldData.Length))
{
int num17 = 0;
if (newOffset < newData.Length)
{
num14 = 0;
int num19 = 0;
for (int j = 1; (newOffset >= (num9 + j)) && (pos >= j); j++)
{
if (oldData[pos - j] == newData[newOffset - j])
{
num14++;
}
if (((num14 * 2) - j) > ((num19 * 2) - num17))
{
num19 = num14;
num17 = j;
}
}
}
if ((num9 + num16) > (newOffset - num17))
{
int num21 = (num9 + num16) - (newOffset - num17);
num14 = 0;
int num22 = 0;
int num23 = 0;
int num24 = 0;
while (true)
{
if (num24 >= num21)
{
num16 += num23 - num21;
num17 -= num23;
break;
}
if (newData[((num9 + num16) - num21) + num24] == oldData[((num10 + num16) - num21) + num24])
{
num14++;
}
if (newData[(newOffset - num17) + num24] == oldData[(pos - num17) + num24])
{
num14--;
}
if (num14 > num22)
{
num22 = num14;
num23 = num24 + 1;
}
num24++;
}
}
int num25 = 0;
while (true)
{
if (num25 >= num16)
{
int num26 = 0;
while (true)
{
if (num26 >= ((newOffset - num17) - (num9 + num16)))
{
count += num16;
num3 += (newOffset - num17) - (num9 + num16);
byte[] buffer4 = new byte[8];
WriteInt64((long)num16, buffer4, 0);
stream2.Write(buffer4, 0, 8);
WriteInt64((long)((newOffset - num17) - (num9 + num16)), buffer4, 0);
stream2.Write(buffer4, 0, 8);
WriteInt64((long)((pos - num17) - (num10 + num16)), buffer4, 0);
stream2.Write(buffer4, 0, 8);
num9 = newOffset - num17;
num10 = pos - num17;
num11 = pos - newOffset;
break;
}
buffer3[num3 + num26] = newData[(num9 + num16) + num26];
num26++;
}
break;
}
buffer[count + num25] = (byte)(newData[num9 + num25] - oldData[num10 + num25]);
num25++;
}
break;
}
if (oldData[num10 + num18] == newData[num9 + num18])
{
num14++;
}
num18++;
if (((num14 * 2) - num18) > ((num15 * 2) - num16))
{
num15 = num14;
num16 = num18;
}
}
}
TR_0059:
while (true)
{
if (newOffset < newData.Length)
{
num12 = 0;
int num1 = newOffset + num8;
int index = newOffset = num1;
while (true)
{
if (newOffset >= newData.Length)
{
break;
}
num8 = Search(i, oldData, newData, newOffset, 0, oldData.Length, out pos);
while (true)
{
if (index < (newOffset + num8))
{
if (((index + num11) < oldData.Length) && (oldData[index + num11] == newData[index]))
{
num12++;
}
index++;
continue;
}
if (((num8 != num12) || (num8 == 0)) && (num8 <= (num12 + 8)))
{
if (((newOffset + num11) < oldData.Length) && (oldData[newOffset + num11] == newData[newOffset]))
{
num12--;
}
newOffset++;
break;
}
break;
}
}
}
else
{
goto TR_0021;
}
break;
}
goto TR_0049;
}
}
TR_0021:
num4 = output.Position;
WriteInt64((num4 - position) - 0x20, buf, 8);
using (WrappingStream stream3 = new WrappingStream(output, Ownership.None))
{
using (BZip2OutputStream stream4 = new BZip2OutputStream(stream3))
{
stream4.Write(buffer, 0, count);
}
}
WriteInt64(output.Position - num4, buf, 0x10);
using (WrappingStream stream5 = new WrappingStream(output, Ownership.None))
{
using (BZip2OutputStream stream6 = new BZip2OutputStream(stream5))
{
stream6.Write(buffer3, 0, num3);
}
}
long num5 = output.Position;
output.Position = position;
output.Write(buf, 0, buf.Length);
output.Position = num5;
}
