itoas.cpp

#include "itoas.h"
 
char* ltoa( long value, char *string, int radix )
{
  char tmp[33];
  char *tp = tmp;
  long i;
  unsigned long v;
  int sign;
  char *sp;
  if ( string == NULL )
  {
    return 0 ;
  }
  if (radix > 36 || radix <= 1)
  {
    return 0 ;
  }
  sign = (radix == 10 && value < 0);
  if (sign)
  {
    v = -value;
  }
  else
  {
    v = (unsigned long)value;
  }
  while (v || tp == tmp)
  {
    i = v % radix;
    v = v / radix;
    if (i < 10)
      *tp++ = i+'0';
    else
      *tp++ = i + 'a' - 10;
  }
  sp = string;
  if (sign)
    *sp++ = '-';
  while (tp > tmp)
    *sp++ = *--tp;
  *sp = 0;
  return string;
}
 
char* ultoa( unsigned long value, char *string, int radix )
{
  char tmp[33];
  char *tp = tmp;
  long i;
  unsigned long v = value;
  char *sp;
  if ( string == NULL )
  {
    return 0;
  }
  if (radix > 36 || radix <= 1)
  {
    return 0;
  }
 
  while (v || tp == tmp)
  {
    i = v % radix;
    v = v / radix;
    if (i < 10)
      *tp++ = i+'0';
    else
      *tp++ = i + 'a' - 10;
  }
  sp = string;
 
  while (tp > tmp)
    *sp++ = *--tp;
  *sp = 0;
  return string;
}
 
 
char* itoa( int value, char *string, int radix )
{
  return ltoa( value, string, radix ) ;
}
 
char* utoa( unsigned long value, char *string, int radix )
{
  return ultoa( value, string, radix ) ;
}