#include "mystdlib.h"
#include <sys/mman.h>
#include <fcntl.h>

static int indexed = -1;
static unsigned char to_lower[] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F,
0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F,
0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F,
0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x5B, 0x5C, 0x5D, 0x5E, 0x5F,
0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F,
0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E, 0x7F,
0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F,
0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D, 0x9E, 0x9F,
0xA0, 0xA1, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAB, 0xAC, 0xAD, 0xAE, 0xAF,
0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB, 0xBC, 0xBD, 0xBE, 0xBF,
0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xCB, 0xCC, 0xCD, 0xCE, 0xCF,
0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xF6, 0xD7, 0xD8, 0xD9, 0xDA, 0xDB, 0xFC, 0xDD, 0xDE, 0xDF,
0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, 0xEA, 0xEB, 0xEC, 0xED, 0xEE, 0xEF,
0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFF
};

int
mystrcasecmp(const unsigned char *s1, const unsigned char *s2) {
  while (to_lower[*s1] == to_lower[*s2++])
    if ( to_lower[*s1++] == '\0' ) return (0);
  return (to_lower[*s1] - to_lower[*--s2]);
}

int
mystrcasecmp2(const unsigned char *s1, const unsigned char *s2) {
  int i = 0;
  while (i++<11 && to_lower[*s1] == to_lower[*s2++])
    if ( to_lower[*s1++] == '\0' ) return (0);
  if( i != 11 )
    return (to_lower[*s1] - to_lower[*--s2]);
}

int cb_compare( const void* a, const void* b) {
  int result;

  result = mystrcasecmp2( 5+(unsigned char*)a, 5+(unsigned char*)b );
  if( result != 0x1000 )
    return result;

  {
    void *myptr1 = mmap( NULL, 1024, PROT_READ, MAP_NOCORE, indexed, 16+(off_t)*(unsigned long*)a );
    void *myptr2 = mmap( NULL, 1024, PROT_READ, MAP_NOCORE, indexed, 16+(off_t)*(unsigned long*)b );

    if( myptr1 && myptr2)
      result = mystrcasecmp( myptr1, myptr2 );
    else {
      fprintf( stderr, "Mapping during sort failed.\n" );
      exit( 1 );
    }
    munmap( myptr1, 1024 );
    munmap( myptr2, 1024 );
  }
  return result;
}

int main( int argc, char **argv ) {
  MAP index   = NULL;

  if( argc != 3 )
  { fputs( "Syntax: sortindex <indexedfile> <indexfile>", stderr); exit( 1 ); }

  if( ( indexed = open( argv[1], O_RDONLY ) ) == -1 )
  { fprintf( stderr, "Could not open file: %s\n", argv[1] ); exit( 1 ); }

  if( !(index = map_file( argv[2], 0 ) ) ) exit( 1 );

  qsort( index->addr, index->size / 16, 16, cb_compare );

  unmap_file( &index );
  close( indexed );

  return 0;
}