#!/usr/local/bin/tcc -run

/*
 * lbainfo.c -- print information about a given LBA
 * jrra 2012
 *
 * Usage: ./lbainfo.c <disk type> <LBA>
 *
 * Example run:
 * > ./lbainfo.c 3 833
 * Disk type: 3
 * LBA: 833
 * pzone: 2
 * vzone: 2
 * size: 17680 bytes
 * offset: 15472720 bytes
 */

#include <stdio.h>
#include <errno.h>

int pzone_tbl1[7][16] = {
/*disk type 0*/  {267, 559, 833, 1125, 1417, 1691, 1965, 2239, 2513, 2717, 2921, 3195, 3469, 3743, 4017, 4291,},
/*disk type 1*/  {267, 559, 833, 1107, 1381, 1673, 1965, 2239, 2513, 2787, 2991, 3195, 3469, 3743, 4017, 4291,},
/*disk type 2*/  {267, 559, 833, 1107, 1381, 1655, 1929, 2221, 2513, 2787, 3061, 3265, 3469, 3743, 4017, 4291,},
/*disk type 3*/  {267, 559, 833, 1107, 1381, 1655, 1929, 2203, 2477, 2769, 3061, 3335, 3539, 3743, 4017, 4291,},
/*disk type 4*/  {267, 559, 833, 1107, 1381, 1655, 1929, 2203, 2477, 2751, 3025, 3317, 3609, 3813, 4017, 4291,},
/*disk type 5*/  {267, 559, 833, 1107, 1381, 1655, 1929, 2133, 2407, 2681, 2955, 3229, 3503, 3795, 4087, 4291,},
/*disk type 6*/  {267, 559, 833, 1107, 1381, 1655, 1929, 2133, 2337, 2611, 2885, 3159, 3433, 3707, 3999, 4291,},
};

int pzone_tbl2[7][16] = {
/*disk type 0*/  { 0,  1,  2, 14, 15,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13,},
/*disk type 1*/  { 0,  1,  2,  3, 13, 14, 15,  4,  5,  6,  7,  8,  9, 10, 11, 12,},
/*disk type 2*/  { 0,  1,  2,  3,  4, 12, 13, 14, 15,  5,  6,  7,  8,  9, 10, 11,},
/*disk type 3*/  { 0,  1,  2,  3,  4,  5, 11, 12, 13, 14, 15,  6,  7,  8,  9, 10,},
/*disk type 4*/  { 0,  1,  2,  3,  4,  5,  6, 10, 11, 12, 13, 14, 15,  7,  8,  9,},
/*disk type 5*/  { 0,  1,  2,  3,  4,  5,  6,  7,  9, 10, 11, 12, 13, 14, 15,  8,},
/*disk type 6*/  { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,},
};

int vzone_tbl[16] = {
  0, 1, 2, 3, 4, 5, 6, 7, 8, 7, 6, 5, 4, 3, 2, 1,
};

int block_size_per_vzone[9] = {
  19720, 18360, 17680, 16320, 14960, 13600, 12240, 10880, 9520,
};


int lba_to_pzone( int type, int lba )
{
  int pzone = 0;
  int i;
  for( i=15; i>=0; i-- )
    if( lba <= pzone_tbl1[type][i] )
      pzone = pzone_tbl2[type][i];
    else
      break;

  return pzone;
}

int pzone_to_vzone( int pzone )
{
  return vzone_tbl[ pzone ];
}

int size_of_lba( int type, int lba )
{
  return block_size_per_vzone[ pzone_to_vzone( lba_to_pzone( type, lba ) ) ];
}

int size_of_sectors( int type, int lba )
{
  return size_of_lba( type, lba ) / 85;
}

int lba_to_offset( int type, int lba )
{
  int offset = 0;
  int i;
  for( i = 0; i<lba; i++ )
    offset += size_of_lba( type, i );
  return offset;
}


int main( int argc, char* argv[] )
{
  if( argc < 3 )
  {
    printf("Usage: lbainfo <disk type> <LBA>\n");
    return 1;
  }

  errno = 0;
  int type = (int)strtol( argv[1], NULL, 0 );
  if( type > 6 || type < 0 || errno != 0 )
  {
    printf("Disk type must be between 0 and 6\n");
    return 2;
  }

  errno = 0;
  int lba  = (int)strtol( argv[2], NULL, 0 );
  if( lba > 4291 || lba < 0 || errno != 0 )
  {
    printf("LBA must be between 0 and 4291\n");
    return 3;
  }

  printf("Disk type: %d\n", type);
  printf("LBA: %d\n", lba);

  int pzone;
  int vzone;
  int size;
  int secsize;
  int offset;

  // First, let's figure out the pzone.
  pzone = lba_to_pzone( type, lba );
  printf("pzone: %d\n", pzone);

  // Let's figure out the vzone.
  vzone = pzone_to_vzone( pzone );
  printf("vzone: %d\n", vzone);

  // Size of this block.
  size = size_of_lba( type, lba );
  printf("block size: %d bytes\n", size);

  // Size of sectors in this block.
  secsize = size_of_sectors( type, lba );
  printf("sector size: %d bytes\n", secsize);

  // Let's figure out the offset.
  offset = lba_to_offset( type, lba );
  printf("offset: %d bytes\n", offset);
}