/*
 * $Id: byte_manager.c 44 2011-02-15 12:32:29Z kaori $
 *
 * Copyright (c) 2002-2011, Communications and Remote Sensing Laboratory, Universite catholique de Louvain (UCL), Belgium
 * Copyright (c) 2002-2011, Professor Benoit Macq
 * Copyright (c) 2010-2011, Kaori Hagihara
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include "byte_manager.h"

#ifdef SERVER
#include "fcgi_stdio.h"
#define logstream FCGI_stdout
#else
#define FCGI_stdout stdout
#define FCGI_stderr stderr
#define logstream stderr
#endif //SERVER


Byte_t * fetch_bytes( int fd, long offset, int size)
{
  Byte_t *data;

  if( lseek( fd, offset, SEEK_SET)==-1){
    fprintf( FCGI_stdout, "Reason: Target broken (fseek error)\r\n");
    fprintf( FCGI_stderr, "Error: error in fetch_bytes( %d, %ld, %d)\n", fd, offset, size);
    return NULL;
  }
  
  data = (Byte_t *)malloc( size);

  if( read( fd, data, size) != size){
    free( data);
    fprintf( FCGI_stdout, "Reason: Target broken (read error)\r\n");
    fprintf( FCGI_stderr, "Error: error in fetch_bytes( %d, %ld, %d)\n", fd, offset, size);
    return NULL;
  }
  return data;
}

Byte_t fetch_1byte( int fd, long offset)
{
  Byte_t code;

  if( lseek( fd, offset, SEEK_SET)==-1){
    fprintf( FCGI_stdout, "Reason: Target broken (seek error)\r\n");
    fprintf( FCGI_stderr, "Error: error in fetch_1byte( %d, %ld)\n", fd, offset);
    return 0;
  }
   
  if( read( fd, &code, 1) != 1){
    fprintf( FCGI_stdout, "Reason: Target broken (read error)\r\n");
    fprintf( FCGI_stderr, "Error: error in fetch_bytes( %d, %ld)\n", fd, offset);
    return 0;
  }
  return code;
}

Byte2_t fetch_2bytebigendian( int fd, long offset)
{
  Byte_t *data;
  Byte2_t code;

  if(!(data = fetch_bytes( fd, offset, 2))){
    fprintf( FCGI_stderr, "Error: error in fetch_2bytebigendian( %d, %ld)\n", fd, offset);
    return 0;
  }
  code = big2(data);
  free( data);

  return code;
}

Byte4_t fetch_4bytebigendian( int fd, long offset)
{
  Byte_t *data;
  Byte4_t code;

  if(!(data = fetch_bytes( fd, offset, 4))){
    fprintf( FCGI_stderr, "Error: error in fetch_4bytebigendian( %d, %ld)\n", fd, offset);
    return 0;
  }
  code = big4(data);
  free( data);

  return code;
}

Byte8_t fetch_8bytebigendian( int fd, long offset)
{
  Byte_t *data;
  Byte8_t code;

  if(!(data = fetch_bytes( fd, offset, 8))){
    fprintf( FCGI_stderr, "Error: error in fetch_8bytebigendian( %d, %ld)\n", fd, offset);
    return 0;
  }
  code = big8(data);
  free( data);

  return code;
}


Byte2_t big2( Byte_t *buf)
{
  return (((Byte2_t) buf[0]) << 8) + ((Byte2_t) buf[1]);
}

Byte4_t big4( Byte_t *buf)
{
  return (((((((Byte4_t) buf[0]) << 8) + ((Byte4_t) buf[1])) << 8)
           + ((Byte4_t) buf[2])) << 8) + ((Byte4_t) buf[3]);
}

Byte8_t big8( Byte_t *buf)
{
  return (((Byte8_t) big4 (buf)) << 32)
        + ((Byte8_t) big4 (buf + 4));
}