1 /* Copyright (C) 1989, 1990, 1991, 1992, 2000, 2004
2    Free Software Foundation, Inc.
3      Written by James Clark (jjc@jclark.com)
4 
5 This file is part of groff.
6 
7 groff 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 groff 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 groff; see the file COPYING.  If not, write to the Free Software
19 Foundation, 51 Franklin St - Fifth Floor, Boston, MA 02110-1301, USA. */
20 
21 #define INT_DIGITS 19		/* enough for 64-bit integer */
22 
23 #ifdef __cplusplus
24 extern "C" {
25 #endif
26 
if_to_a(int i,int decimal_point)27 char *if_to_a(int i, int decimal_point)
28 {
29   /* room for a -, INT_DIGITS digits, a decimal point, and a terminating '\0' */
30   static char buf[INT_DIGITS + 3];
31   char *p = buf + INT_DIGITS + 2;
32   int point = 0;
33   buf[INT_DIGITS + 2] = '\0';
34   /* assert(decimal_point <= INT_DIGITS); */
35   if (i >= 0) {
36     do {
37       *--p = '0' + (i % 10);
38       i /= 10;
39       if (++point == decimal_point)
40 	*--p = '.';
41     } while (i != 0 || point < decimal_point);
42   }
43   else {			/* i < 0 */
44     do {
45       *--p = '0' - (i % 10);
46       i /= 10;
47       if (++point == decimal_point)
48 	*--p = '.';
49     } while (i != 0 || point < decimal_point);
50     *--p = '-';
51   }
52   if (decimal_point > 0) {
53     char *q;
54     /* there must be a dot, so this will terminate */
55     for (q = buf + INT_DIGITS + 2; q[-1] == '0'; --q)
56       ;
57     if (q[-1] == '.') {
58       if (q - 1 == p) {
59 	q[-1] = '0';
60 	q[0] = '\0';
61       }
62       else
63 	q[-1] = '\0';
64     }
65     else
66       *q = '\0';
67   }
68   return p;
69 }
70 
71 #ifdef __cplusplus
72 }
73 #endif
74