1 /*
2 * Copyright 2002 Sun Microsystems, Inc. All rights reserved.
3 * Use is subject to license terms.
4 */
5
6 /*
7 * Copyright (c) 1991, 1993
8 * The Regents of the University of California. All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 */
38
39 #ifndef lint
40 static char sccsid[] = "@(#)genget.c 8.1 (Berkeley) 6/4/93";
41 #endif /* not lint */
42
43 #include <ctype.h>
44 #include <sys/types.h>
45
46 #define LOWER(x) (isupper(x) ? tolower(x) : (x))
47
48 static char *ambiguous; /* special return value for command routines */
49
50 /*
51 * The prefix function returns 0 if *s1 is not a prefix
52 * of *s2. If *s1 exactly matches *s2, the negative of
53 * the length is returned. If *s1 is a prefix of *s2,
54 * the length of *s1 is returned.
55 */
56 int
isprefix(char * s1,char * s2)57 isprefix(char *s1, char *s2)
58 {
59 char *os1;
60 char c1, c2;
61
62 if (*s1 == '\0')
63 return (-1);
64 os1 = s1;
65 c1 = *s1;
66 c2 = *s2;
67 while (LOWER(c1) == LOWER(c2)) {
68 if (c1 == '\0')
69 break;
70 c1 = *++s1;
71 c2 = *++s2;
72 }
73 return (*s1 ? 0 : (*s2 ? (s1 - os1) : (os1 - s1)));
74 }
75
76
77 /*
78 * Get an entry from the table, from what might be a prefix
79 *
80 * name = name to match
81 * table = name entry in table
82 */
83 char **
genget(char * name,char ** table,int stlen)84 genget(char *name, char **table, int stlen)
85 {
86 register char **c, **found;
87 register int n;
88
89 if (name == 0)
90 return (0);
91
92 found = 0;
93 /*LINTED*/
94 for (c = table; *c != NULL; c = (char **)((char *)c + stlen)) {
95 if ((n = isprefix(name, *c)) == 0)
96 continue;
97 if (n < 0) /* exact match */
98 return (c);
99 if (found)
100 return (&ambiguous);
101 found = c;
102 }
103 return (found);
104 }
105
106 /*
107 * Function call version of Ambiguous()
108 */
109 boolean_t
Ambiguous(void * s)110 Ambiguous(void *s)
111 {
112 return ((char **)s == &ambiguous);
113 }
114