diff --git a/src/ICSharpCode.SharpZipLib/AssemblyInfo.cs b/src/ICSharpCode.SharpZipLib/AssemblyInfo.cs
new file mode 100644
index 000000000..5d83ac84f
--- /dev/null
+++ b/src/ICSharpCode.SharpZipLib/AssemblyInfo.cs
@@ -0,0 +1,3 @@
+using System.Runtime.CompilerServices;
+
+[assembly: InternalsVisibleTo("ICSharpCode.SharpZipLib.Tests, PublicKey = 0024000004800000940000000602000000240000525341310004000001000100b9a14ea8fc9d7599e0e82a1292a23103f0210e2f928a0f466963af23fffadba59dcc8c9e26ecd114d7c0b4179e4bc93b1656b7ee2d4a67dd7c1992653e0d9cc534f7914b6f583b022e0a7aa8a430f407932f9a6806f0fc64d61e78d5ae01aa8f8233196719d44da2c50a2d1cfa3f7abb7487b3567a4f0456aa6667154c6749b1")]
diff --git a/src/ICSharpCode.SharpZipLib/Checksum/BZip2Crc.cs b/src/ICSharpCode.SharpZipLib/Checksum/BZip2Crc.cs
index 9674dcec7..118542868 100644
--- a/src/ICSharpCode.SharpZipLib/Checksum/BZip2Crc.cs
+++ b/src/ICSharpCode.SharpZipLib/Checksum/BZip2Crc.cs
@@ -1,3 +1,4 @@
+using ICSharpCode.SharpZipLib.Checksum.Proxy;
using System;
namespace ICSharpCode.SharpZipLib.Checksum
@@ -5,183 +6,10 @@ namespace ICSharpCode.SharpZipLib.Checksum
///
/// CRC-32 with unreversed data and reversed output
///
- ///
- /// Generate a table for a byte-wise 32-bit CRC calculation on the polynomial:
- /// x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x^1+x^0.
- ///
- /// Polynomials over GF(2) are represented in binary, one bit per coefficient,
- /// with the lowest powers in the most significant bit. Then adding polynomials
- /// is just exclusive-or, and multiplying a polynomial by x is a right shift by
- /// one. If we call the above polynomial p, and represent a byte as the
- /// polynomial q, also with the lowest power in the most significant bit (so the
- /// byte 0xb1 is the polynomial x^7+x^3+x+1), then the CRC is (q*x^32) mod p,
- /// where a mod b means the remainder after dividing a by b.
- ///
- /// This calculation is done using the shift-register method of multiplying and
- /// taking the remainder. The register is initialized to zero, and for each
- /// incoming bit, x^32 is added mod p to the register if the bit is a one (where
- /// x^32 mod p is p+x^32 = x^26+...+1), and the register is multiplied mod p by
- /// x (which is shifting right by one and adding x^32 mod p if the bit shifted
- /// out is a one). We start with the highest power (least significant bit) of
- /// q and repeat for all eight bits of q.
- ///
- /// The table is simply the CRC of all possible eight bit values. This is all
- /// the information needed to generate CRC's on data a byte at a time for all
- /// combinations of CRC register values and incoming bytes.
- ///
- public sealed class BZip2Crc : IChecksum
+ public sealed class BZip2Crc : Crc32Base
{
- #region Instance Fields
+ private static readonly NormalCrc32Proxy _proxy = new NormalCrc32Proxy();
- private const uint crcInit = 0xFFFFFFFF;
- //const uint crcXor = 0x00000000;
-
- private static readonly uint[] crcTable = {
- 0X00000000, 0X04C11DB7, 0X09823B6E, 0X0D4326D9,
- 0X130476DC, 0X17C56B6B, 0X1A864DB2, 0X1E475005,
- 0X2608EDB8, 0X22C9F00F, 0X2F8AD6D6, 0X2B4BCB61,
- 0X350C9B64, 0X31CD86D3, 0X3C8EA00A, 0X384FBDBD,
- 0X4C11DB70, 0X48D0C6C7, 0X4593E01E, 0X4152FDA9,
- 0X5F15ADAC, 0X5BD4B01B, 0X569796C2, 0X52568B75,
- 0X6A1936C8, 0X6ED82B7F, 0X639B0DA6, 0X675A1011,
- 0X791D4014, 0X7DDC5DA3, 0X709F7B7A, 0X745E66CD,
- 0X9823B6E0, 0X9CE2AB57, 0X91A18D8E, 0X95609039,
- 0X8B27C03C, 0X8FE6DD8B, 0X82A5FB52, 0X8664E6E5,
- 0XBE2B5B58, 0XBAEA46EF, 0XB7A96036, 0XB3687D81,
- 0XAD2F2D84, 0XA9EE3033, 0XA4AD16EA, 0XA06C0B5D,
- 0XD4326D90, 0XD0F37027, 0XDDB056FE, 0XD9714B49,
- 0XC7361B4C, 0XC3F706FB, 0XCEB42022, 0XCA753D95,
- 0XF23A8028, 0XF6FB9D9F, 0XFBB8BB46, 0XFF79A6F1,
- 0XE13EF6F4, 0XE5FFEB43, 0XE8BCCD9A, 0XEC7DD02D,
- 0X34867077, 0X30476DC0, 0X3D044B19, 0X39C556AE,
- 0X278206AB, 0X23431B1C, 0X2E003DC5, 0X2AC12072,
- 0X128E9DCF, 0X164F8078, 0X1B0CA6A1, 0X1FCDBB16,
- 0X018AEB13, 0X054BF6A4, 0X0808D07D, 0X0CC9CDCA,
- 0X7897AB07, 0X7C56B6B0, 0X71159069, 0X75D48DDE,
- 0X6B93DDDB, 0X6F52C06C, 0X6211E6B5, 0X66D0FB02,
- 0X5E9F46BF, 0X5A5E5B08, 0X571D7DD1, 0X53DC6066,
- 0X4D9B3063, 0X495A2DD4, 0X44190B0D, 0X40D816BA,
- 0XACA5C697, 0XA864DB20, 0XA527FDF9, 0XA1E6E04E,
- 0XBFA1B04B, 0XBB60ADFC, 0XB6238B25, 0XB2E29692,
- 0X8AAD2B2F, 0X8E6C3698, 0X832F1041, 0X87EE0DF6,
- 0X99A95DF3, 0X9D684044, 0X902B669D, 0X94EA7B2A,
- 0XE0B41DE7, 0XE4750050, 0XE9362689, 0XEDF73B3E,
- 0XF3B06B3B, 0XF771768C, 0XFA325055, 0XFEF34DE2,
- 0XC6BCF05F, 0XC27DEDE8, 0XCF3ECB31, 0XCBFFD686,
- 0XD5B88683, 0XD1799B34, 0XDC3ABDED, 0XD8FBA05A,
- 0X690CE0EE, 0X6DCDFD59, 0X608EDB80, 0X644FC637,
- 0X7A089632, 0X7EC98B85, 0X738AAD5C, 0X774BB0EB,
- 0X4F040D56, 0X4BC510E1, 0X46863638, 0X42472B8F,
- 0X5C007B8A, 0X58C1663D, 0X558240E4, 0X51435D53,
- 0X251D3B9E, 0X21DC2629, 0X2C9F00F0, 0X285E1D47,
- 0X36194D42, 0X32D850F5, 0X3F9B762C, 0X3B5A6B9B,
- 0X0315D626, 0X07D4CB91, 0X0A97ED48, 0X0E56F0FF,
- 0X1011A0FA, 0X14D0BD4D, 0X19939B94, 0X1D528623,
- 0XF12F560E, 0XF5EE4BB9, 0XF8AD6D60, 0XFC6C70D7,
- 0XE22B20D2, 0XE6EA3D65, 0XEBA91BBC, 0XEF68060B,
- 0XD727BBB6, 0XD3E6A601, 0XDEA580D8, 0XDA649D6F,
- 0XC423CD6A, 0XC0E2D0DD, 0XCDA1F604, 0XC960EBB3,
- 0XBD3E8D7E, 0XB9FF90C9, 0XB4BCB610, 0XB07DABA7,
- 0XAE3AFBA2, 0XAAFBE615, 0XA7B8C0CC, 0XA379DD7B,
- 0X9B3660C6, 0X9FF77D71, 0X92B45BA8, 0X9675461F,
- 0X8832161A, 0X8CF30BAD, 0X81B02D74, 0X857130C3,
- 0X5D8A9099, 0X594B8D2E, 0X5408ABF7, 0X50C9B640,
- 0X4E8EE645, 0X4A4FFBF2, 0X470CDD2B, 0X43CDC09C,
- 0X7B827D21, 0X7F436096, 0X7200464F, 0X76C15BF8,
- 0X68860BFD, 0X6C47164A, 0X61043093, 0X65C52D24,
- 0X119B4BE9, 0X155A565E, 0X18197087, 0X1CD86D30,
- 0X029F3D35, 0X065E2082, 0X0B1D065B, 0X0FDC1BEC,
- 0X3793A651, 0X3352BBE6, 0X3E119D3F, 0X3AD08088,
- 0X2497D08D, 0X2056CD3A, 0X2D15EBE3, 0X29D4F654,
- 0XC5A92679, 0XC1683BCE, 0XCC2B1D17, 0XC8EA00A0,
- 0XD6AD50A5, 0XD26C4D12, 0XDF2F6BCB, 0XDBEE767C,
- 0XE3A1CBC1, 0XE760D676, 0XEA23F0AF, 0XEEE2ED18,
- 0XF0A5BD1D, 0XF464A0AA, 0XF9278673, 0XFDE69BC4,
- 0X89B8FD09, 0X8D79E0BE, 0X803AC667, 0X84FBDBD0,
- 0X9ABC8BD5, 0X9E7D9662, 0X933EB0BB, 0X97FFAD0C,
- 0XAFB010B1, 0XAB710D06, 0XA6322BDF, 0XA2F33668,
- 0XBCB4666D, 0XB8757BDA, 0XB5365D03, 0XB1F740B4
- };
-
- ///
- /// The CRC data checksum so far.
- ///
- private uint checkValue;
-
- #endregion Instance Fields
-
- ///
- /// Initialise a default instance of
- ///
- public BZip2Crc()
- {
- Reset();
- }
-
- ///
- /// Resets the CRC data checksum as if no update was ever called.
- ///
- public void Reset()
- {
- checkValue = crcInit;
- }
-
- ///
- /// Returns the CRC data checksum computed so far.
- ///
- /// Reversed Out = true
- public long Value
- {
- get
- {
- // Tehcnically, the output should be:
- //return (long)(~checkValue ^ crcXor);
- // but x ^ 0 = x, so there is no point in adding
- // the XOR operation
- return (long)(~checkValue);
- }
- }
-
- ///
- /// Updates the checksum with the int bval.
- ///
- ///
- /// the byte is taken as the lower 8 bits of bval
- ///
- /// Reversed Data = false
- public void Update(int bval)
- {
- checkValue = unchecked(crcTable[(byte)(((checkValue >> 24) & 0xFF) ^ bval)] ^ (checkValue << 8));
- }
-
- ///
- /// Updates the CRC data checksum with the bytes taken from
- /// a block of data.
- ///
- /// Contains the data to update the CRC with.
- public void Update(byte[] buffer)
- {
- if (buffer == null)
- {
- throw new ArgumentNullException(nameof(buffer));
- }
-
- Update(new ArraySegment(buffer, 0, buffer.Length));
- }
-
- ///
- /// Update CRC data checksum based on a portion of a block of data
- ///
- ///
- /// The chunk of data to add
- ///
- public void Update(ArraySegment segment)
- {
- var count = segment.Count;
- var offset = segment.Offset;
-
- while (--count >= 0)
- Update(segment.Array[offset++]);
- }
+ internal override Crc32ProxyBase Proxy => _proxy;
}
}
diff --git a/src/ICSharpCode.SharpZipLib/Checksum/Crc32.cs b/src/ICSharpCode.SharpZipLib/Checksum/Crc32.cs
index 9b8ab4b6d..75700bcee 100644
--- a/src/ICSharpCode.SharpZipLib/Checksum/Crc32.cs
+++ b/src/ICSharpCode.SharpZipLib/Checksum/Crc32.cs
@@ -1,3 +1,4 @@
+using ICSharpCode.SharpZipLib.Checksum.Proxy;
using System;
namespace ICSharpCode.SharpZipLib.Checksum
@@ -5,172 +6,18 @@ namespace ICSharpCode.SharpZipLib.Checksum
///
/// CRC-32 with reversed data and unreversed output
///
- ///
- /// Generate a table for a byte-wise 32-bit CRC calculation on the polynomial:
- /// x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x^1+x^0.
- ///
- /// Polynomials over GF(2) are represented in binary, one bit per coefficient,
- /// with the lowest powers in the most significant bit. Then adding polynomials
- /// is just exclusive-or, and multiplying a polynomial by x is a right shift by
- /// one. If we call the above polynomial p, and represent a byte as the
- /// polynomial q, also with the lowest power in the most significant bit (so the
- /// byte 0xb1 is the polynomial x^7+x^3+x+1), then the CRC is (q*x^32) mod p,
- /// where a mod b means the remainder after dividing a by b.
- ///
- /// This calculation is done using the shift-register method of multiplying and
- /// taking the remainder. The register is initialized to zero, and for each
- /// incoming bit, x^32 is added mod p to the register if the bit is a one (where
- /// x^32 mod p is p+x^32 = x^26+...+1), and the register is multiplied mod p by
- /// x (which is shifting right by one and adding x^32 mod p if the bit shifted
- /// out is a one). We start with the highest power (least significant bit) of
- /// q and repeat for all eight bits of q.
- ///
- /// The table is simply the CRC of all possible eight bit values. This is all
- /// the information needed to generate CRC's on data a byte at a time for all
- /// combinations of CRC register values and incoming bytes.
- ///
- public sealed class Crc32 : IChecksum
+ public sealed class Crc32 : Crc32Base
{
- #region Instance Fields
+ private static readonly ReflectedCrc32Proxy _proxy = new ReflectedCrc32Proxy();
+
+ internal override Crc32ProxyBase Proxy => _proxy;
- private static readonly uint crcInit = 0xFFFFFFFF;
- private static readonly uint crcXor = 0xFFFFFFFF;
-
- private static readonly uint[] crcTable = {
- 0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419,
- 0x706AF48F, 0xE963A535, 0x9E6495A3, 0x0EDB8832, 0x79DCB8A4,
- 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07,
- 0x90BF1D91, 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE,
- 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, 0x136C9856,
- 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9,
- 0xFA0F3D63, 0x8D080DF5, 0x3B6E20C8, 0x4C69105E, 0xD56041E4,
- 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
- 0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3,
- 0x45DF5C75, 0xDCD60DCF, 0xABD13D59, 0x26D930AC, 0x51DE003A,
- 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599,
- 0xB8BDA50F, 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924,
- 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, 0x76DC4190,
- 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F,
- 0x9FBFE4A5, 0xE8B8D433, 0x7807C9A2, 0x0F00F934, 0x9609A88E,
- 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
- 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED,
- 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 0x65B0D9C6, 0x12B7E950,
- 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3,
- 0xFBD44C65, 0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2,
- 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB, 0x4369E96A,
- 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5,
- 0xAA0A4C5F, 0xDD0D7CC9, 0x5005713C, 0x270241AA, 0xBE0B1010,
- 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
- 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17,
- 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD, 0xEDB88320, 0x9ABFB3B6,
- 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615,
- 0x73DC1683, 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8,
- 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1, 0xF00F9344,
- 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB,
- 0x196C3671, 0x6E6B06E7, 0xFED41B76, 0x89D32BE0, 0x10DA7A5A,
- 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
- 0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1,
- 0xA6BC5767, 0x3FB506DD, 0x48B2364B, 0xD80D2BDA, 0xAF0A1B4C,
- 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF,
- 0x4669BE79, 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236,
- 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, 0xC5BA3BBE,
- 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31,
- 0x2CD99E8B, 0x5BDEAE1D, 0x9B64C2B0, 0xEC63F226, 0x756AA39C,
- 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
- 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B,
- 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, 0x86D3D2D4, 0xF1D4E242,
- 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1,
- 0x18B74777, 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C,
- 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45, 0xA00AE278,
- 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7,
- 0x4969474D, 0x3E6E77DB, 0xAED16A4A, 0xD9D65ADC, 0x40DF0B66,
- 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
- 0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605,
- 0xCDD70693, 0x54DE5729, 0x23D967BF, 0xB3667A2E, 0xC4614AB8,
- 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B,
- 0x2D02EF8D
- };
-
- ///
- /// The CRC data checksum so far.
- ///
- private uint checkValue;
-
- #endregion Instance Fields
internal static uint ComputeCrc32(uint oldCrc, byte bval)
{
- return (uint)(Crc32.crcTable[(oldCrc ^ bval) & 0xFF] ^ (oldCrc >> 8));
- }
-
- ///
- /// Initialise a default instance of
- ///
- public Crc32()
- {
- Reset();
+ return ~_proxy.Append(~oldCrc, new [] { bval }, 0, 1);
}
- ///
- /// Resets the CRC data checksum as if no update was ever called.
- ///
- public void Reset()
- {
- checkValue = crcInit;
- }
-
- ///
- /// Returns the CRC data checksum computed so far.
- ///
- /// Reversed Out = false
- public long Value
- {
- get
- {
- return (long)(checkValue ^ crcXor);
- }
- }
- ///
- /// Updates the checksum with the int bval.
- ///
- ///
- /// the byte is taken as the lower 8 bits of bval
- ///
- /// Reversed Data = true
- public void Update(int bval)
- {
- checkValue = unchecked(crcTable[(checkValue ^ bval) & 0xFF] ^ (checkValue >> 8));
- }
-
- ///
- /// Updates the CRC data checksum with the bytes taken from
- /// a block of data.
- ///
- /// Contains the data to update the CRC with.
- public void Update(byte[] buffer)
- {
- if (buffer == null)
- {
- throw new ArgumentNullException(nameof(buffer));
- }
-
- Update(new ArraySegment(buffer, 0, buffer.Length));
- }
-
- ///
- /// Update CRC data checksum based on a portion of a block of data
- ///
- ///
- /// The chunk of data to add
- ///
- public void Update(ArraySegment segment)
- {
- var count = segment.Count;
- var offset = segment.Offset;
-
- while (--count >= 0)
- Update(segment.Array[offset++]);
- }
}
}
diff --git a/src/ICSharpCode.SharpZipLib/Checksum/Crc32Base.cs b/src/ICSharpCode.SharpZipLib/Checksum/Crc32Base.cs
new file mode 100644
index 000000000..d3b30c26c
--- /dev/null
+++ b/src/ICSharpCode.SharpZipLib/Checksum/Crc32Base.cs
@@ -0,0 +1,96 @@
+using ICSharpCode.SharpZipLib.Checksum.Proxy;
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace ICSharpCode.SharpZipLib.Checksum
+{
+ ///
+ /// Base class for CRC32 checksums
+ ///
+ public abstract class Crc32Base : IChecksum
+ {
+ #region Instance Fields
+ ///
+ /// The CRC data checksum so far.
+ ///
+ private uint checkValue;
+
+ #endregion
+
+
+ ///
+ /// Initialise a default instance of
+ ///
+ protected Crc32Base()
+ {
+ Reset();
+ }
+
+
+ internal abstract Crc32ProxyBase Proxy { get; }
+
+
+
+ ///
+ /// Resets the CRC data checksum as if no update was ever called.
+ ///
+ public void Reset()
+ {
+ checkValue = 0;
+ }
+
+ ///
+ /// Returns the CRC data checksum computed so far.
+ ///
+ /// Reversed Out = false
+ public long Value
+ {
+ get
+ {
+ return (long)(checkValue);
+ }
+ }
+
+ ///
+ /// Updates the checksum with the int bval.
+ ///
+ ///
+ /// the byte is taken as the lower 8 bits of bval
+ ///
+ /// Reversed Data = true
+ public void Update(int bval)
+ {
+ checkValue = Proxy.Append(checkValue, new [] { (byte)bval }, 0, 1);
+ }
+
+
+
+ ///
+ /// Updates the CRC data checksum with the bytes taken from
+ /// a block of data.
+ ///
+ /// Contains the data to update the CRC with.
+ public void Update(byte[] buffer)
+ {
+ if (buffer == null)
+ {
+ throw new ArgumentNullException(nameof(buffer));
+ }
+
+ Update(new ArraySegment(buffer, 0, buffer.Length));
+ }
+
+ ///
+ /// Update CRC data checksum based on a portion of a block of data
+ ///
+ ///
+ /// The chunk of data to add
+ ///
+ public void Update(ArraySegment segment)
+ {
+ checkValue = Proxy.Append(checkValue, segment.Array, segment.Offset, segment.Count);
+ }
+
+ }
+}
diff --git a/src/ICSharpCode.SharpZipLib/Checksum/Proxy/Crc32ProxyBase.cs b/src/ICSharpCode.SharpZipLib/Checksum/Proxy/Crc32ProxyBase.cs
new file mode 100644
index 000000000..33ec81cfd
--- /dev/null
+++ b/src/ICSharpCode.SharpZipLib/Checksum/Proxy/Crc32ProxyBase.cs
@@ -0,0 +1,101 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Text;
+
+namespace ICSharpCode.SharpZipLib.Checksum.Proxy
+{
+ /*
+ * This is heavily based on Crc32.NET: https://github.com/force-net/Crc32.NET/blob/develop/Crc32.NET/SafeProxy.cs
+ * Commit hash: fbc1061b0cb53df2322d5aed33167a2e6335970b: https://github.com/force-net/Crc32.NET/tree/fbc1061b0cb53df2322d5aed33167a2e6335970b
+ *
+ * Then modified for BZIP2 CRC using the excellent CRC32 description from Michaelangel007: https://github.com/Michaelangel007/crc32
+ *
+ * Original comment from CRC32.NET:
+ * This is .NET safe implementation of Crc32 algorithm.
+ * This implementation was investigated as fastest from different variants. It based on Robert Vazan native implementations of Crc32C
+ * Also, it is good for x64 and for x86, so, it seems, there is no sense to do 2 different realizations.
+ *
+ * Addition: some speed increase was found with splitting xor to 4 independent blocks. Also, some attempts to optimize unaligned tails was unsuccessfull (JIT limitations?).
+ *
+ *
+ * Max Vysokikh, 2016-2017
+ */
+ internal abstract class Crc32ProxyBase
+ {
+ private readonly uint[] _table = new uint[16 * 256];
+
+ protected Crc32ProxyBase()
+ {
+ Init();
+ }
+
+ protected abstract uint InitLookupValue(uint index);
+ protected abstract uint CalculateLookupValue(uint lookupValue);
+ protected abstract uint CalculateCrc(uint crc, byte input, uint[] lookupTable);
+
+
+
+ private void Init()
+ {
+ var table = _table;
+ for (uint i = 0; i < 256; i++)
+ {
+ uint lookupVal = InitLookupValue(i);
+ for (int t = 0; t < 16; t++)
+ {
+ for (int k = 0; k < 8; k++)
+ {
+ lookupVal = CalculateLookupValue(lookupVal);
+ }
+ table[(t * 256) + i] = lookupVal;
+ }
+ }
+ }
+
+
+
+ public uint Append(uint crc, byte[] input, int startOffset, int startLength)
+ {
+ uint crcLocal = uint.MaxValue ^ crc;
+ uint[] table = _table;
+ int offset = startOffset;
+ int length = startLength;
+
+ while (length >= 16)
+ {
+ var a = table[(3 * 256) + input[offset + 12]]
+ ^ table[(2 * 256) + input[offset + 13]]
+ ^ table[(1 * 256) + input[offset + 14]]
+ ^ table[(0 * 256) + input[offset + 15]];
+
+ var b = table[(7 * 256) + input[offset + 8]]
+ ^ table[(6 * 256) + input[offset + 9]]
+ ^ table[(5 * 256) + input[offset + 10]]
+ ^ table[(4 * 256) + input[offset + 11]];
+
+ var c = table[(11 * 256) + input[offset + 4]]
+ ^ table[(10 * 256) + input[offset + 5]]
+ ^ table[(9 * 256) + input[offset + 6]]
+ ^ table[(8 * 256) + input[offset + 7]];
+
+ var d = table[(15 * 256) + ((byte)crcLocal ^ input[offset])]
+ ^ table[(14 * 256) + ((byte)(crcLocal >> 8) ^ input[offset + 1])]
+ ^ table[(13 * 256) + ((byte)(crcLocal >> 16) ^ input[offset + 2])]
+ ^ table[(12 * 256) + ((crcLocal >> 24) ^ input[offset + 3])];
+
+ crcLocal = d ^ c ^ b ^ a;
+ offset += 16;
+ length -= 16;
+ }
+
+ while (--length >= 0)
+ {
+ crcLocal = CalculateCrc(crcLocal, input[offset++], table);
+ }
+
+ return crcLocal ^ uint.MaxValue;
+ }
+
+ }
+}
diff --git a/src/ICSharpCode.SharpZipLib/Checksum/Proxy/NormalCrc32Proxy.cs b/src/ICSharpCode.SharpZipLib/Checksum/Proxy/NormalCrc32Proxy.cs
new file mode 100644
index 000000000..6c27c68ee
--- /dev/null
+++ b/src/ICSharpCode.SharpZipLib/Checksum/Proxy/NormalCrc32Proxy.cs
@@ -0,0 +1,25 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace ICSharpCode.SharpZipLib.Checksum.Proxy
+{
+ internal class NormalCrc32Proxy : Crc32ProxyBase
+ {
+
+ private readonly uint _poly = 0x04C11DB7;
+
+
+ protected override uint CalculateCrc(uint crc, byte input, uint[] lookupTable)
+ {
+ return lookupTable[(byte)(((crc >> 24) & 0xFF) ^ input)] ^ (crc << 8);
+ }
+
+ protected override uint CalculateLookupValue(uint lookupValue)
+ {
+ return (lookupValue & (1L << 31)) > 0 ? _poly ^ (lookupValue << 1) : (lookupValue << 1);
+ }
+
+ protected override uint InitLookupValue(uint index) => index << 24;
+ }
+}
diff --git a/src/ICSharpCode.SharpZipLib/Checksum/Proxy/ReflectedCrc32Proxy.cs b/src/ICSharpCode.SharpZipLib/Checksum/Proxy/ReflectedCrc32Proxy.cs
new file mode 100644
index 000000000..1274a6d4f
--- /dev/null
+++ b/src/ICSharpCode.SharpZipLib/Checksum/Proxy/ReflectedCrc32Proxy.cs
@@ -0,0 +1,25 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace ICSharpCode.SharpZipLib.Checksum.Proxy
+{
+ internal class ReflectedCrc32Proxy : Crc32ProxyBase
+ {
+
+ private readonly uint _poly = 0xEDB88320u;
+
+
+ protected override uint CalculateCrc(uint crc, byte input, uint[] lookupTable)
+ {
+ return lookupTable[(byte)(crc ^ input)] ^ (crc >> 8);
+ }
+
+ protected override uint CalculateLookupValue(uint lookupValue)
+ {
+ return (lookupValue & 1) == 1 ? _poly ^ (lookupValue >> 1) : (lookupValue >> 1);
+ }
+
+ protected override uint InitLookupValue(uint index) => index;
+ }
+}
diff --git a/test/ICSharpCode.SharpZipLib.Tests/Checksum/Adler32Tests.cs b/test/ICSharpCode.SharpZipLib.Tests/Checksum/Adler32Tests.cs
new file mode 100644
index 000000000..6b6160745
--- /dev/null
+++ b/test/ICSharpCode.SharpZipLib.Tests/Checksum/Adler32Tests.cs
@@ -0,0 +1,50 @@
+using ICSharpCode.SharpZipLib.Checksum;
+using NUnit.Framework;
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Text;
+
+namespace ICSharpCode.SharpZipLib.Tests.Checksum
+{
+
+ [TestFixture]
+ public class Adler32Tests : ChecksumTestBase
+ {
+ [Test]
+ public void Adler_32()
+ {
+ var underTestAdler32 = new Adler32();
+ Assert.AreEqual(0x00000001, underTestAdler32.Value);
+
+ underTestAdler32.Update(check);
+ Assert.AreEqual(0x091E01DE, underTestAdler32.Value);
+
+ underTestAdler32.Reset();
+ Assert.AreEqual(0x00000001, underTestAdler32.Value);
+
+ exceptionTesting(underTestAdler32);
+ }
+
+ const long BufferSize = 256 * 1024 * 1024;
+
+ [Test]
+ public void Adler_32_Performance()
+ {
+ var rand = new Random(1);
+
+ var buffer = new byte[BufferSize];
+ rand.NextBytes(buffer);
+
+ var adler = new Adler32();
+ Assert.AreEqual(0x00000001, adler.Value);
+
+ adler.Update(buffer);
+
+ adler.Update(check);
+ Assert.AreEqual(0xD4897DA3, adler.Value);
+
+ exceptionTesting(adler);
+ }
+ }
+}
diff --git a/test/ICSharpCode.SharpZipLib.Tests/Checksum/Bzip2CrcTests.cs b/test/ICSharpCode.SharpZipLib.Tests/Checksum/Bzip2CrcTests.cs
new file mode 100644
index 000000000..a7f10fc40
--- /dev/null
+++ b/test/ICSharpCode.SharpZipLib.Tests/Checksum/Bzip2CrcTests.cs
@@ -0,0 +1,36 @@
+using ICSharpCode.SharpZipLib.Checksum;
+using NUnit.Framework;
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace ICSharpCode.SharpZipLib.Tests.Checksum
+{
+ [TestFixture]
+ public class Bzip2CrcTests : ChecksumTestBase
+ {
+
+
+ [Test]
+ public void CRC_32_BZip2()
+ {
+ var underTestBZip2Crc = new BZip2Crc();
+ Assert.AreEqual(0x0, underTestBZip2Crc.Value);
+
+ underTestBZip2Crc.Update(check);
+ Assert.AreEqual(0xFC891918, underTestBZip2Crc.Value);
+
+ underTestBZip2Crc.Reset();
+ Assert.AreEqual(0x0, underTestBZip2Crc.Value);
+
+ underTestBZip2Crc.Update(longcheck);
+ Assert.AreEqual(0xA12ADA2B, underTestBZip2Crc.Value);
+
+ underTestBZip2Crc.Reset();
+ Assert.AreEqual(0x0, underTestBZip2Crc.Value);
+
+ exceptionTesting(underTestBZip2Crc);
+ }
+
+ }
+}
diff --git a/test/ICSharpCode.SharpZipLib.Tests/Checksum/ChecksumTestBase.cs b/test/ICSharpCode.SharpZipLib.Tests/Checksum/ChecksumTestBase.cs
new file mode 100644
index 000000000..a52fc59af
--- /dev/null
+++ b/test/ICSharpCode.SharpZipLib.Tests/Checksum/ChecksumTestBase.cs
@@ -0,0 +1,95 @@
+using ICSharpCode.SharpZipLib.Checksum;
+using NUnit.Framework;
+using System;
+using System.Diagnostics;
+
+namespace ICSharpCode.SharpZipLib.Tests.Checksum
+{
+ public abstract class ChecksumTestBase
+ {
+ protected readonly
+ // Represents ASCII string of "123456789"
+ byte[] check = { 49, 50, 51, 52, 53, 54, 55, 56, 57 };
+
+ protected readonly
+ // Represents ASCII string of "123456789123456789123456789"
+ byte[] longcheck = { 49, 50, 51, 52, 53, 54, 55, 56, 57, 49, 50, 51, 52, 53, 54, 55, 56, 57, 49, 50, 51, 52, 53, 54, 55, 56, 57 };
+
+
+
+ protected void exceptionTesting(IChecksum crcUnderTest)
+ {
+ bool exception = false;
+
+ try
+ {
+ crcUnderTest.Update(null);
+ }
+ catch (ArgumentNullException)
+ {
+ exception = true;
+ }
+ Assert.IsTrue(exception, "Passing a null buffer should cause an ArgumentNullException");
+
+ // reset exception
+ exception = false;
+ try
+ {
+ crcUnderTest.Update(new ArraySegment(null, 0, 0));
+ }
+ catch (ArgumentNullException)
+ {
+ exception = true;
+ }
+ Assert.IsTrue(exception, "Passing a null buffer should cause an ArgumentNullException");
+
+ // reset exception
+ exception = false;
+ try
+ {
+ crcUnderTest.Update(new ArraySegment(check, -1, 9));
+ }
+ catch (ArgumentOutOfRangeException)
+ {
+ exception = true;
+ }
+ Assert.IsTrue(exception, "Passing a negative offset should cause an ArgumentOutOfRangeException");
+
+ // reset exception
+ exception = false;
+ try
+ {
+ crcUnderTest.Update(new ArraySegment(check, 10, 0));
+ }
+ catch (ArgumentException)
+ {
+ exception = true;
+ }
+ Assert.IsTrue(exception, "Passing an offset greater than buffer.Length should cause an ArgumentException");
+
+ // reset exception
+ exception = false;
+ try
+ {
+ crcUnderTest.Update(new ArraySegment(check, 0, -1));
+ }
+ catch (ArgumentOutOfRangeException)
+ {
+ exception = true;
+ }
+ Assert.IsTrue(exception, "Passing a negative count should cause an ArgumentOutOfRangeException");
+
+ // reset exception
+ exception = false;
+ try
+ {
+ crcUnderTest.Update(new ArraySegment(check, 0, 10));
+ }
+ catch (ArgumentException)
+ {
+ exception = true;
+ }
+ Assert.IsTrue(exception, "Passing a count + offset greater than buffer.Length should cause an ArgumentException");
+ }
+ }
+}
diff --git a/test/ICSharpCode.SharpZipLib.Tests/Checksum/Crc32Tests.cs b/test/ICSharpCode.SharpZipLib.Tests/Checksum/Crc32Tests.cs
new file mode 100644
index 000000000..9637080d1
--- /dev/null
+++ b/test/ICSharpCode.SharpZipLib.Tests/Checksum/Crc32Tests.cs
@@ -0,0 +1,69 @@
+using ICSharpCode.SharpZipLib.Checksum;
+using NUnit.Framework;
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace ICSharpCode.SharpZipLib.Tests.Checksum
+{
+
+ [TestFixture]
+ public class Crc32Tests : ChecksumTestBase
+ {
+
+ [Test]
+ public void CRC_32()
+ {
+ var underTestCrc32 = new Crc32();
+ Assert.AreEqual(0x0, underTestCrc32.Value);
+
+ underTestCrc32.Update(check);
+ Assert.AreEqual(0xCBF43926, underTestCrc32.Value);
+
+ underTestCrc32.Reset();
+ Assert.AreEqual(0x0, underTestCrc32.Value);
+
+ underTestCrc32.Update(longcheck);
+ Assert.AreEqual(0x4DDF6E59, underTestCrc32.Value);
+
+ underTestCrc32.Reset();
+ Assert.AreEqual(0x0, underTestCrc32.Value);
+
+ exceptionTesting(underTestCrc32);
+ }
+
+
+ [Test]
+ public void CRC_32_Byte_For_Byte()
+ {
+ var underTestCrc32 = new Crc32();
+ Assert.AreEqual(0x0, underTestCrc32.Value);
+
+ foreach (byte b in check)
+ {
+ underTestCrc32.Update((int)b);
+ }
+ Assert.AreEqual(0xCBF43926, underTestCrc32.Value);
+
+ underTestCrc32.Reset();
+ Assert.AreEqual(0x0, underTestCrc32.Value);
+
+ underTestCrc32.Update(longcheck);
+ Assert.AreEqual(0x4DDF6E59, underTestCrc32.Value);
+
+ underTestCrc32.Reset();
+ Assert.AreEqual(0x0, underTestCrc32.Value);
+
+ exceptionTesting(underTestCrc32);
+ }
+
+
+ [Test]
+ public void CRC32_ComputeCrc32_Produces_Correct_Result()
+ {
+ Assert.AreEqual(0x19F6D6AB, Crc32.ComputeCrc32(0x9AE0DAAF, 57));
+ Assert.AreEqual(0xAA0D1792, Crc32.ComputeCrc32(0x75BCD15, 123));
+ Assert.AreEqual(0xF6280B5B, Crc32.ComputeCrc32(0x912D00C0, 21));
+ }
+ }
+}
diff --git a/test/ICSharpCode.SharpZipLib.Tests/ICSharpCode.SharpZipLib.Tests.csproj b/test/ICSharpCode.SharpZipLib.Tests/ICSharpCode.SharpZipLib.Tests.csproj
index 324f04721..24f25efbc 100644
--- a/test/ICSharpCode.SharpZipLib.Tests/ICSharpCode.SharpZipLib.Tests.csproj
+++ b/test/ICSharpCode.SharpZipLib.Tests/ICSharpCode.SharpZipLib.Tests.csproj
@@ -5,6 +5,8 @@
netcoreapp2.0
+ true
+ ICSharpCode.SharpZipLib.snk