libgroff/itoa.c

   1 /* Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
   2      Written by James Clark (jjc@jclark.com)
   3
   4 This file is part of groff.
   5
   6 groff is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 2, or (at your option) any later
   9 version.
  10
  11 groff is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License along
  17 with groff; see the file COPYING.  If not, write to the Free Software
  18 Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
  19
  20 #define INT_DIGITS 19           /* enough for 64 bit integer */
  21
  22 char *itoa(i)
  23      int i;
  24 {
  25   /* Room for INT_DIGITS digits, - and '\0' */
  26   static char buf[INT_DIGITS + 2];
  27   char *p = buf + INT_DIGITS + 1;       /* points to terminating '\0' */
  28   if (i >= 0) {
  29     do {
  30       *--p = '0' + (i % 10);
  31       i /= 10;
  32     } while (i != 0);
  33     return p;
  34   }
  35   else {                        /* i < 0 */
  36     do {
  37       *--p = '0' - (i % 10);
  38       i /= 10;
  39     } while (i != 0);
  40     *--p = '-';
  41   }
  42   return p;
  43 }