lib/sh/itos.c

   1 /* itos.c -- Convert integer to string. */
   2
   3 /* Copyright (C) 1998, Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   7    Bash is free software; you can redistribute it and/or modify it under
   8    the terms of the GNU General Public License as published by the Free
   9    Software Foundation; either version 2, or (at your option) any later
  10    version.
  11
  12    Bash is distributed in the hope that it will be useful, but WITHOUT ANY
  13    WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15    for more details.
  16
  17    You should have received a copy of the GNU General Public License along
  18    with Bash; see the file COPYING.  If not, write to the Free Software
  19    Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
  20
  21 #include <config.h>
  22
  23 #if defined (HAVE_UNISTD_H)
  24 #  include <unistd.h>
  25 #endif
  26
  27 #include "bashansi.h"
  28 #include "shell.h"
  29
  30 /* Number of characters that can appear in a string representation
  31    of an integer.  32 is larger than the string rep of 2^^31 - 1. */
  32 #define MAX_INT_LEN 32
  33
  34 /* Integer to string conversion.  The caller passes the buffer and
  35    the size.  This should check for buffer underflow, but currently
  36    does not. */
  37 char *
  38 inttostr (i, buf, len)
  39      int i;
  40      char *buf;
  41      int len;
  42 {
  43   char *p;
  44   int negative = 0;
  45   unsigned int ui;
  46
  47   if (i < 0)
  48     {
  49       negative++;
  50       i = -i;
  51     }
  52
  53   ui = (unsigned int) i;
  54
  55   p = buf + len - 2;
  56   p[1] = '\0';
  57
  58   do
  59     *p-- = (ui % 10) + '0';
  60   while (ui /= 10);
  61
  62   if (negative)
  63     *p-- = '-';
  64
  65   return (p + 1);
  66 }
  67
  68 /* Integer to string conversion.  This conses the string; the
  69    caller should free it. */
  70 char *
  71 itos (i)
  72      int i;
  73 {
  74   char *p, lbuf[MAX_INT_LEN];
  75
  76   p = inttostr (i, lbuf, sizeof(lbuf));
  77   return (savestring (p));
  78 }