public static byte[] Compress(byte[] input)
{
var compressionArray = new byte[input.Length + 2];
var compressedLength = SnappyCompress.Compress(SnappyByteBuffer.NewSync(compressionArray), SnappyByteBuffer.NewSync(input));
var output = new byte[compressedLength];
Array.Copy(compressionArray, output, compressedLength);
return(output);
}
public static bool TryCompress(ref SnappyByteBuffer data, int maxSizeInPercent)
{
var compressed = SnappyByteBuffer.NewAsync(new byte[data.Length * (long)maxSizeInPercent / 100]);
var compressedLength = Compress(compressed, data);
if (compressedLength < 0)
{
return(false);
}
data = SnappyByteBuffer.NewAsync(compressed.Buffer, 0, compressedLength);
return(true);
}
public SnappyByteBuffer ResizingAppend(SnappyByteBuffer append)
{
if (AsyncSafe)
{
if (Offset + Length + append.Length <= Buffer.Length)
{
Array.Copy(append.Buffer, append.Offset, Buffer, Offset + Length, append.Length);
return(NewAsync(Buffer, Offset, Length + append.Length));
}
}
var newCapacity = Math.Max(Length + append.Length, Length * 2);
var newBuffer = new byte[newCapacity];
Array.Copy(Buffer, Offset, newBuffer, 0, Length);
Array.Copy(append.Buffer, append.Offset, newBuffer, Length, append.Length);
return(NewAsync(newBuffer, 0, Length + append.Length));
}
public static SnappyByteBuffer Decompress(SnappyByteBuffer compressedBytes)
{
int ofs;
var decompressedSize = DecompressedSize(compressedBytes, out ofs);
if (decompressedSize < 0)
{
throw new InvalidDataException();
}
var dst = new byte[decompressedSize];
var dstBuf = SnappyByteBuffer.NewAsync(dst);
if (!DecompressRaw(dstBuf, SnappyByteBuffer.NewSync(compressedBytes.Buffer, compressedBytes.Offset + ofs, compressedBytes.Length - ofs)))
{
throw new InvalidDataException();
}
return(dstBuf);
}
public static byte[] Decompress(byte[] input)
{
var buffer = SnappyDecompress.Decompress(SnappyByteBuffer.NewSync(input));
return(buffer.ToByteArray());
}
public static int DecompressedSize(SnappyByteBuffer compressedBytes, out int length)
{
var offset = compressedBytes.Offset;
var limit = offset + compressedBytes.Length;
var buf = compressedBytes.Buffer;
if (offset >= limit)
{
goto error;
}
var b = buf[offset];
offset++;
var result = (uint)(b & 127);
if (b < 128)
{
goto done;
}
if (offset >= limit)
{
goto error;
}
b = buf[offset];
offset++;
result |= ((uint)(b & 127) << 7);
if (b < 128)
{
goto done;
}
if (offset >= limit)
{
goto error;
}
b = buf[offset];
offset++;
result |= ((uint)(b & 127) << 14);
if (b < 128)
{
goto done;
}
if (offset >= limit)
{
goto error;
}
b = buf[offset];
offset++;
result |= ((uint)(b & 127) << 21);
if (b < 128)
{
goto done;
}
if (offset >= limit)
{
goto error;
}
b = buf[offset];
offset++;
result |= ((uint)(b & 127) << 28);
if (b >= 16)
{
goto error;
}
done:
length = offset - compressedBytes.Offset;
return((int)result);
error:
length = 0;
return(-1);
}
public static bool DecompressRaw(SnappyByteBuffer dstBuf, SnappyByteBuffer srcBuf)
{
var src = srcBuf.Buffer;
var dst = dstBuf.Buffer;
var s = srcBuf.Offset;
var d = dstBuf.Offset;
var sL = srcBuf.Length;
var dL = dstBuf.Length;
int len = 0;
int o = 0;
while (sL > 0)
{
var b = src[s];
s++;
sL--;
switch (b & 3)
{
case 0:
len = b >> 2;
if (len < 60)
{
len++;
}
else if (len == 60)
{
if (sL < 1)
{
return(false);
}
len = src[s] + 1;
s++;
sL--;
}
else if (len == 61)
{
if (sL < 2)
{
return(false);
}
len = src[s] + 0x100 * src[s + 1] + 1;
s += 2;
sL -= 2;
}
else if (len == 62)
{
if (sL < 3)
{
return(false);
}
len = src[s] + 0x100 * src[s + 1] + 0x10000 * src[s + 2] + 1;
s += 3;
sL -= 3;
}
else
{
if (sL < 4)
{
return(false);
}
len = src[s] + 0x100 * src[s + 1] + 0x10000 * src[s + 2] + 0x1000000 * src[s + 3] + 1;
s += 3;
sL -= 3;
}
if (len <= 0)
{
return(false);
}
if (len > dL || len > sL)
{
return(false);
}
Array.Copy(src, s, dst, d, len);
s += len;
d += len;
sL -= len;
dL -= len;
continue;
case 1:
if (sL < 1)
{
return(false);
}
len = 4 + ((b >> 2) & 7);
o = (b & 0xe0) << 3 | src[s];
s++;
sL--;
break;
case 2:
if (sL < 2)
{
return(false);
}
len = 1 + (b >> 2);
o = src[s] + src[s + 1] * 0x100;
s += 2;
sL -= 2;
break;
case 3:
return(false);
}
var end = d + len;
if (o > d || len > dL)
{
return(false);
}
for (; d < end; d++)
{
dst[d] = dst[d - o];
}
dL -= len;
}
return(dL == 0);
}
public static int Compress(SnappyByteBuffer dstBuf, SnappyByteBuffer srcBuf)
{
var src = srcBuf.Buffer;
var dst = dstBuf.Buffer;
var s = srcBuf.Offset;
var d = dstBuf.Offset;
var sL = srcBuf.Length;
var dL = dstBuf.Length;
if (dL < 5)
{
return(-1);
}
EmitLength(dst, ref d, ref dL, sL);
if (sL <= 4)
{
if (!EmitLiteral(dst, ref d, ref dL, src, s, sL))
{
return(-1);
}
return(d - dstBuf.Offset);
}
var shift = 32 - 8;
var tableSize = 1 << 8;
while (tableSize < 1 << 14 && tableSize < sL)
{
shift--;
tableSize *= 2;
}
var table = new int[tableSize];
for (int i = 0; i < tableSize; i++)
{
table[i] = -1;
}
var lit = s;
while (sL > 3)
{
var v = src[s] | ((uint)src[s + 1]) << 8 | ((uint)src[s + 2]) << 16 | ((uint)src[s + 3]) << 24;
nextfast:
var h = (v * 0x1e35a7bd) >> shift;
var t = table[h];
table[h] = s;
if (t < 0 || s - t >= MaxOffset || !Equal4(src, t, s))
{
s++;
sL--;
if (sL > 3)
{
v = (v >> 8) | ((uint)src[s + 3]) << 24;
goto nextfast;
}
break;
}
if (lit != s)
{
if (!EmitLiteral(dst, ref d, ref dL, src, lit, s - lit))
{
return(-1);
}
}
var s0 = s;
s += 4;
sL -= 4;
t += 4;
while (sL > 0 && src[s] == src[t])
{
s++;
sL--;
t++;
}
if (!EmitCopy(dst, ref d, ref dL, s - t, s - s0))
{
return(-1);
}
lit = s;
}
s += sL;
if (lit != s)
{
if (!EmitLiteral(dst, ref d, ref dL, src, lit, s - lit))
{
return(-1);
}
}
return(d - dstBuf.Offset);
}
