/*
!===============================================================================
!
! Copyright (C) 1998-2006 Hinnerk Stueben
!                    2010 Yoshifumi Nakamura
!
! This file is part of BQCD -- Berlin Quantum ChromoDynamics program
!
! BQCD is free software: you can redistribute it and/or modify
! it under the terms of the GNU General Public License as published by
! the Free Software Foundation, either version 3 of the License, or
! (at your option) any later version.
!
! BQCD is distributed in the hope that it will be useful,
! but WITHOUT ANY WARRANTY; without even the implied warranty of
! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
! GNU General Public License for more details.
!
! You should have received a copy of the GNU General Public License
! along with BQCD.  If not, see <http://www.gnu.org/licenses/>.
!
!-----------------------------------------------------------------------------
!
! Adapted from:
!
! ==================
! QCD SF/T3E PROGRAM
! ==================
!
! Calculate a modified cyclic redundancy check (CRC is specified by the
! POSIX.2 standard). Modification is necessary since I do not know how
! to handle a unsigned long in FORTRAN. Solution: CKSUM returns negative
! number if result is > LONG_MAX.
!
! CKSUM_GET() returns always positive numbers < LONG_MAX. (H.S.)
!
!
! Parts of the source come from cksum.c of the GNU text utilities (version
! 1.19) written by Q. Frank Xia.
!
! $Log: c_cksum.c,v $
! Revision 1.1  1997/12/04 10:31:09  pleiter
! Initial writing attempt
!
!-----------------------------------------------------------------------------
*/
# include "c_defs.h"
# include "cksum.h"

static unsigned INT8 the_crc = 0;
static INT8 the_bytes = 0;

static unsigned INT8 const crctab[256] =
{
  0x0,
  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
};

void CKSUM_INIT(void)
{
  the_crc = 0;
  the_bytes = 0;
}

void CKSUM_ADD(void *memptr, INT8 *nbytes)
{
  register unsigned INT8   crc;
  register INT8            i;
  register unsigned char   *cp;

  crc    = the_crc;
  cp     = (unsigned char *) memptr;
  for (i=0; i < *nbytes; i++)
    crc = (crc << 8) ^ crctab[((crc >> 24) ^ *(cp++)) & 0xFF];

  the_crc = crc;
  the_bytes += *nbytes;
}

void CKSUM_GET(INT8 *total_crc, INT8 *total_bytes)
{
  register unsigned INT8   crc;
  register INT8            i;

  crc = the_crc;

  for (i = the_bytes; i > 0; i >>= 8)
    crc = (crc << 8) ^ crctab[((crc >> 24) ^ i) & 0xFF];
  crc = (~crc & 0xFFFFFFFF);

  *total_crc = (INT8) crc;
  *total_bytes = the_bytes;
}

/*--------------------------------------------------------------------------*/
//
// add for para IO, 2010/07/01 yn
//
#ifndef NONMPI
#include <mpi.h>
#include <stdio.h>
/*
void CKSUM_ADD_MPI()
{
  int status;
  unsigned INT8 the_crc_tmp;
  INT8 the_bytes_tmp;



  unsigned long send= (unsigned long) the_crc;
  unsigned long recv;

  fprintf(stderr,"CKSUM_ADD_MPI crc before %lu \n",send);
  status = MPI_Allreduce( (void *)&send, (void *)&recv, 1,
			  MPI_UNSIGNED_LONG, MPI_BXOR, MPI_COMM_WORLD);
  fprintf(stderr,"CKSUM_ADD_MPI crc after %lu \n",recv);

  status = MPI_Allreduce( (void *)&the_bytes, (void *)&the_bytes_tmp, 1,
			  MPI_LONG_LONG, MPI_SUM, MPI_COMM_WORLD);



  the_crc=(unsigned INT8) recv;
  the_bytes=the_bytes_tmp;
}
*/

void CKSUM_BCAST(int *np)
{
#ifdef MPI_1
    /* this may not work wtih MPI-1*/
  MPI_Bcast ( (void *)&the_crc,   1, MPI_DOUBLE, *np, MPI_COMM_WORLD ) ;
#else
  MPI_Bcast ( (void *)&the_crc,   1, MPI_UNSIGNED_LONG_LONG, *np, MPI_COMM_WORLD ) ;
#endif
  MPI_Bcast ( (void *)&the_bytes, 1, MPI_LONG_LONG,          *np, MPI_COMM_WORLD ) ;
}

#else
void CKSUM_ADD_MPI(){}
void CKSUM_BCAST(int *np){}
#endif
