1/*-
2 * Copyright (c) 1991, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include <config.h>
35#ifdef HAVE_SYS_TYPES_H
36#include <sys/types.h>
37#endif
38#include <ctype.h>
39#include "misc-proto.h"
40
41RCSID("$Id$");
42
43
44#define	LOWER(x) (isupper(x) ? tolower(x) : (x))
45/*
46 * The prefix function returns 0 if *s1 is not a prefix
47 * of *s2.  If *s1 exactly matches *s2, the negative of
48 * the length is returned.  If *s1 is a prefix of *s2,
49 * the length of *s1 is returned.
50 */
51
52int
53isprefix(char *s1, char *s2)
54{
55    char *os1;
56    char c1, c2;
57
58    if (*s1 == '\0')
59	return(-1);
60    os1 = s1;
61    c1 = *s1;
62    c2 = *s2;
63    while (tolower((unsigned char)c1) == tolower((unsigned char)c2)) {
64	if (c1 == '\0')
65	    break;
66	c1 = *++s1;
67	c2 = *++s2;
68    }
69    return(*s1 ? 0 : (*s2 ? (s1 - os1) : (os1 - s1)));
70}
71
72static char *ambiguous;		/* special return value for command routines */
73
74char **
75genget(char *name, char **table, int stlen)
76     /* name to match */
77     /* name entry in table */
78
79{
80    char **c, **found;
81    int n;
82
83    if (name == 0)
84	return 0;
85
86    found = 0;
87    for (c = table; *c != 0; c = (char **)((char *)c + stlen)) {
88	if ((n = isprefix(name, *c)) == 0)
89	    continue;
90	if (n < 0)		/* exact match */
91	    return(c);
92	if (found)
93	    return(&ambiguous);
94	found = c;
95    }
96    return(found);
97}
98
99/*
100 * Function call version of Ambiguous()
101 */
102int
103Ambiguous(void *s)
104{
105    return((char **)s == &ambiguous);
106}
107