xref: /openbsd-src/gnu/usr.bin/cvs/diff/cmpbuf.c (revision 2286d8ed900f26153a3cd5227a124b1c0adce72f)
1*2286d8edStholo /* Buffer primitives for comparison operations.
2*2286d8edStholo    Copyright (C) 1993 Free Software Foundation, Inc.
3*2286d8edStholo 
4*2286d8edStholo    This program is free software; you can redistribute it and/or modify
5*2286d8edStholo    it under the terms of the GNU General Public License as published by
6*2286d8edStholo    the Free Software Foundation; either version 2, or (at your option)
7*2286d8edStholo    any later version.
8*2286d8edStholo 
9*2286d8edStholo    This program is distributed in the hope that it will be useful,
10*2286d8edStholo    but WITHOUT ANY WARRANTY; without even the implied warranty of
11*2286d8edStholo    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12*2286d8edStholo    GNU General Public License for more details.
13*2286d8edStholo 
14*2286d8edStholo    You should have received a copy of the GNU General Public License
15*2286d8edStholo    along with this program; if not, write to the Free Software
16*2286d8edStholo    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
17*2286d8edStholo 
18*2286d8edStholo #include "system.h"
19*2286d8edStholo #include "cmpbuf.h"
20*2286d8edStholo 
21*2286d8edStholo /* Least common multiple of two buffer sizes A and B.  */
22*2286d8edStholo 
23*2286d8edStholo size_t
24*2286d8edStholo buffer_lcm (a, b)
25*2286d8edStholo      size_t a, b;
26*2286d8edStholo {
27*2286d8edStholo   size_t m, n, r;
28*2286d8edStholo 
29*2286d8edStholo   /* Yield reasonable values if buffer sizes are zero.  */
30*2286d8edStholo   if (!a)
31*2286d8edStholo     return b ? b : 8 * 1024;
32*2286d8edStholo   if (!b)
33*2286d8edStholo     return a;
34*2286d8edStholo 
35*2286d8edStholo   /* n = gcd (a, b) */
36*2286d8edStholo   for (m = a, n = b;  (r = m % n) != 0;  m = n, n = r)
37*2286d8edStholo     continue;
38*2286d8edStholo 
39*2286d8edStholo   return a/n * b;
40*2286d8edStholo }
41