xref: /titanic_41/usr/src/lib/libast/common/string/strsort.c (revision 3e14f97f673e8a630f076077de35afdd43dc1587)
1  /***********************************************************************
2  *                                                                      *
3  *               This software is part of the ast package               *
4  *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
5  *                      and is licensed under the                       *
6  *                  Common Public License, Version 1.0                  *
7  *                    by AT&T Intellectual Property                     *
8  *                                                                      *
9  *                A copy of the License is available at                 *
10  *            http://www.opensource.org/licenses/cpl1.0.txt             *
11  *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12  *                                                                      *
13  *              Information and Software Systems Research               *
14  *                            AT&T Research                             *
15  *                           Florham Park NJ                            *
16  *                                                                      *
17  *                 Glenn Fowler <gsf@research.att.com>                  *
18  *                  David Korn <dgk@research.att.com>                   *
19  *                   Phong Vo <kpv@research.att.com>                    *
20  *                                                                      *
21  ***********************************************************************/
22  #pragma prototyped
23  /*
24   *  strsort - sort an array pointers using fn
25   *
26   *	fn follows strcmp(3) conventions
27   *
28   *   David Korn
29   *   AT&T Bell Laboratories
30   *
31   *  derived from Bourne Shell
32   */
33  
34  #include <ast.h>
35  
36  void
strsort(char ** argv,int n,int (* fn)(const char *,const char *))37  strsort(char** argv, int n, int(*fn)(const char*, const char*))
38  {
39  	register int 	i;
40  	register int 	j;
41  	register int 	m;
42  	register char**	ap;
43  	char*		s;
44  	int 		k;
45  
46  	for (j = 1; j <= n; j *= 2);
47  	for (m = 2 * j - 1; m /= 2;)
48  		for (j = 0, k = n - m; j < k; j++)
49  			for (i = j; i >= 0; i -= m)
50  			{
51  				ap = &argv[i];
52  				if ((*fn)(ap[m], ap[0]) >= 0) break;
53  				s = ap[m];
54  				ap[m] = ap[0];
55  				ap[0] = s;
56  			}
57  }
58