XrdOucCRC.cc

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/******************************************************************************/
/*                                                                            */
/*                        X r d O u c C R C 3 2 . c c                         */
/*                                                                            */
/*   Produced by Andrew Hanushevsky for Stanford University under contract    */
/*              DE-AC02-76-SFO0515 with the Department of Energy              */
/*                                                                            */
/* This file is part of the XRootD software suite.                            */
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/******************************************************************************/
 
/*
   C++ implementation of CRC-32 checksums.  Code is based
   upon and utilizes algorithm published by Ross Williams
   as initially implemented by Eric Durbin.
 
   This file contains:
      CRC lookup table
      function CalcCRC32 for calculating CRC-32 checksum
 
   Provided by:
      Eric Durbin
      Kentucky Cancer Registry
      University of Kentucky
      October 14, 1998
 
   Status:
      Public Domain
*/
 
#include "XrdOuc/XrdOucCRC.hh"
#include "XrdOuc/XrdOucCRC32C.hh"
 
/*****************************************************************/
/*                                                               */
/* CRC LOOKUP TABLE                                              */
/* ================                                              */
/* The following CRC lookup table was generated automagically    */
/* by the Rocksoft^tm Model CRC Algorithm Table Generation       */
/* Program V1.0 using the following model parameters:            */
/*                                                               */
/*    Width   : 4 bytes.                                         */
/*    Poly    : 0x04C11DB7L                                      */
/*    Reverse : TRUE.                                            */
/*                                                               */
/* For more information on the Rocksoft^tm Model CRC Algorithm,  */
/* see the document titled "A Painless Guide to CRC Error        */
/* Detection Algorithms" by Ross Williams                        */
/* (ross@guest.adelaide.edu.au.). This document is likely to be  */
/* in the FTP archive "ftp.adelaide.edu.au/pub/rocksoft".        */
/*                                                               */
/*****************************************************************/
 
unsigned int XrdOucCRC::crctable[256] =
{
 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
};
 
/*****************************************************************/
/*                   End of CRC Lookup Table                     */
/*****************************************************************/
 
/******************************************************************************/
/*                                 C R C 3 2                                  */
/******************************************************************************/
 
/* Calculate CRC-32 Checksum for NAACCR Record,
   skipping area of record containing checksum field.
 
   Uses reflected table driven method documented by Ross Williams.
 
   PARAMETERS:
     unsigned char *p           Record Buffer
     unsigned long reclen       Record Length
 
   RETURNS:
     checksum value
 
   Author:
     Eric Durbin 1998-10-14
     Simplified by Andrew Hanushevsky 2007-07-20
 
   Status:
     Public Domain
 
   Changes:
     Compute CRC for complete buffer
     Use unsigned int instead of long to insure 32 bit values.
     Make this a C++ class.
*/
uint32_t XrdOucCRC::CRC32(const unsigned char *p, int reclen)
{
   const unsigned int CRC32_XINIT = 0xffffffff;
   const unsigned int CRC32_XOROT = 0xffffffff;
   unsigned int crc = CRC32_XINIT;
 
// Process each byte
//
   while(reclen-- > 0) crc = crctable[(crc ^ *p++) & 0xff] ^ (crc >> 8);
 
// Return XOR out value
//
   return crc ^ CRC32_XOROT;
}
 
/******************************************************************************/
/*                                C R C 3 2 C                                 */
/******************************************************************************/
 
uint32_t XrdOucCRC::Calc32C(const void* data, size_t count, uint32_t prevcs)
{
 
// Return the checksum
//
   return crc32c(prevcs, data, count);
}
 
/******************************************************************************/
 
void XrdOucCRC::Calc32C(const void* data, size_t count, uint32_t* csval)
{
   int i, numpages = count/XrdSys::PageSize;
   const uint8_t* dataP = (const uint8_t*)data;
 
// Calculate the CRC32C for each page
//
   for (i = 0; i < numpages; i++)
       {csval[i] = crc32c(0, dataP, XrdSys::PageSize);
        count -= XrdSys::PageSize;
        dataP += XrdSys::PageSize;
       }
 
// if there is anything left, calculate that as well
//
   if (count > 0) csval[i] = crc32c(0, dataP, count);
}
 
/******************************************************************************/
/*                            C o m b i n e 3 2 C                             */
/******************************************************************************/
 
uint32_t XrdOucCRC::Combine32C(uint32_t Cksum1, uint32_t Cksum2, int DLen)
{
   return crc32c_combine(Cksum1, Cksum2, (size_t)DLen);
}
 
/******************************************************************************/
/*                                V e r 3 2 C                                 */
/******************************************************************************/
 
bool XrdOucCRC::Ver32C(const void*    data,  size_t    count,
                       const uint32_t csval, uint32_t* valcs)
{
   uint32_t actualCS;
 
// Verify the checksum
//
   actualCS = crc32c(0, data, count);
   if (valcs) *valcs = actualCS;
   return csval == actualCS;
}
 
/******************************************************************************/
 
int  XrdOucCRC::Ver32C(const void*     data,  size_t    count,
                       const uint32_t* csval, uint32_t& valcs)
{
   int i, numpages = count/XrdSys::PageSize;
   const uint8_t* dataP = (const uint8_t*)data;
   uint32_t actualCS;
 
// Calculate the CRC32C for each page and make sure it is the same.
//
   for (i = 0; i < numpages; i++)
       {
        actualCS = crc32c(0, dataP, XrdSys::PageSize);
        if (csval[i] != actualCS)
           {valcs = actualCS;
            return i;
           }
        count -= XrdSys::PageSize;
        dataP += XrdSys::PageSize;
       }
 
// if there is anything left, verify that as well
//
   if (count > 0)
      {
       actualCS = crc32c(0, dataP, count);
       if (csval[i] != actualCS)
          {valcs = actualCS;
           return i;
          }
      }
 
// Everything matched.
//
   return -1;
}
 
/******************************************************************************/
 
bool XrdOucCRC::Ver32C(const void*     data,  size_t count,
                       const uint32_t* csval, bool*  valok)
{
   int i, numpages = count/XrdSys::PageSize;
   const uint8_t* dataP = (const uint8_t*)data;
   uint32_t actualCS;
   bool retval = true;
 
// Calculate the CRC32C for each page and make sure it is the same.
//
   for (i = 0; i < numpages; i++)
       {
        actualCS = crc32c(0, dataP, XrdSys::PageSize);
        if (csval[i] == actualCS) valok[i] = true;
           else valok[i] = retval = false;
        count -= XrdSys::PageSize;
        dataP += XrdSys::PageSize;
       }
 
// if there is anything left, verify that as well
//
   if (count > 0)
      {
       actualCS = crc32c(0, dataP, count);
       if (csval[i] == actualCS) valok[i] = true;
           else valok[i] = retval = false;
      }
 
// All done.
//
   return retval;
}
 
/******************************************************************************/
 
bool XrdOucCRC::Ver32C(const void*     data,  size_t    count,
                       const uint32_t* csval, uint32_t* valcs)
{
   int i, numpages = count/XrdSys::PageSize;
   const uint8_t* dataP = (const uint8_t*)data;
   bool retval = true;
 
// Calculate the CRC32C for each page and make sure it is the same.
//
   for (i = 0; i < numpages; i++)
       {
        valcs[i] = crc32c(0, dataP, XrdSys::PageSize);
        if (csval[i] != valcs[i]) retval = false;
        count -= XrdSys::PageSize;
        dataP += XrdSys::PageSize;
       }
 
// if there is anything left, verify that as well
//
   if (count > 0)
      {
       valcs[i] = crc32c(0, dataP, count);
       if (csval[i] != valcs[i]) retval = false;
      }
 
// All done.
//
   return retval;
}