int2bin.c

/* int2bin.h - Routines to convert long integer to binary string */

/* Copyright (c) 2014 by Allen Yu
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
 * PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 *  */

#include "int2bin.h"

void int2bin_evenpad(long decimal, char *binary)
{
  int  k = 0, n = 0;
  int  neg_flag = 0;
  int  remain;
  char temp[80];
 
  // take care of negative input
  if (decimal < 0)
  {      
    decimal = -decimal;
    neg_flag = 1;
  }
  do 
  {
    remain    = decimal % 2;
    // whittle down the decimal number
    decimal   = decimal / 2;
    // converts digit 0 or 1 to character '0' or '1'
    temp[k++] = remain + '0';
  } while (decimal > 0);
  while (k%2!=0){
    temp[k++]='0';
  }
  if (neg_flag)
    temp[k++] = '-';       // add - sign
  
  // reverse the spelling
  while (k >= 0)
    binary[n++] = temp[--k];
 
  binary[n-1] = 0;         // end with NULL

}

void int2bin(long decimal, char *binary)
{
  int  k = 0, n = 0;
  int  neg_flag = 0;
  int  remain;
  char temp[80];
 
  // take care of negative input
  if (decimal < 0)
  {      
    decimal = -decimal;
    neg_flag = 1;
  }
  do 
  {
    remain    = decimal % 2;
    // whittle down the decimal number
    decimal   = decimal / 2;
    // converts digit 0 or 1 to character '0' or '1'
    temp[k++] = remain + '0';
  } while (decimal > 0);
 
  while (k<32){
    temp[k++]='0';
  }
  if (neg_flag)
    temp[k++] = '-';       // add - sign
  
  // reverse the spelling
  while (k >= 0)
    binary[n++] = temp[--k];
 
  binary[n-1] = 0;         // end with NULL

}