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 #ifndef lint 35 /* from: static char sccsid[] = "@(#)genget.c 8.2 (Berkeley) 5/30/95"; */ 36 static char *rcsid = "$NetBSD: genget.c,v 1.5 1996/02/24 01:15:21 jtk Exp $"; 37 #endif /* not lint */ 38 39 40 #include <ctype.h> 41 #include "misc-proto.h" 42 43 int isprefix __P((char *, char *)); 44 char **genget __P((char *, char **, int)); 45 int Ambiguous __P((char *)); 46 47 #define LOWER(x) (isupper(x) ? tolower(x) : (x)) 48 /* 49 * The prefix function returns 0 if *s1 is not a prefix 50 * of *s2. If *s1 exactly matches *s2, the negative of 51 * the length is returned. If *s1 is a prefix of *s2, 52 * the length of *s1 is returned. 53 */ 54 int 55 isprefix(s1, s2) 56 register char *s1, *s2; 57 { 58 register int n = 0; 59 char *os1; 60 register 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 static char *ambiguous; /* special return value for command routines */ 77 78 char ** 79 genget(name, table, stlen) 80 char *name; /* name to match */ 81 char **table; /* name entry in table */ 82 int stlen; 83 { 84 register char **c, **found; 85 register int n; 86 87 if (name == 0) 88 return 0; 89 90 found = 0; 91 for (c = table; *c != 0; c = (char **)((char *)c + stlen)) { 92 if ((n = isprefix(name, *c)) == 0) 93 continue; 94 if (n < 0) /* exact match */ 95 return(c); 96 if (found) 97 return(&ambiguous); 98 found = c; 99 } 100 return(found); 101 } 102 103 /* 104 * Function call version of Ambiguous() 105 */ 106 int 107 Ambiguous(s) 108 char *s; 109 { 110 return((char **)s == &ambiguous); 111 } 112