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 * @(#)genget.c 8.2 (Berkeley) 5/30/95 34 * $FreeBSD: src/lib/libtelnet/genget.c,v 1.2.8.1 2002/04/13 11:07:12 markm Exp $ 35 * $DragonFly: src/lib/libtelnet/genget.c,v 1.2 2003/06/17 04:26:51 dillon Exp $ 36 */ 37 38 #include <ctype.h> 39 40 #include "misc-proto.h" 41 42 #define LOWER(x) (isupper(x) ? tolower(x) : (x)) 43 /* 44 * The prefix function returns 0 if *s1 is not a prefix 45 * of *s2. If *s1 exactly matches *s2, the negative of 46 * the length is returned. If *s1 is a prefix of *s2, 47 * the length of *s1 is returned. 48 */ 49 int 50 isprefix(char *s1, const char *s2) 51 { 52 char *os1; 53 char c1, c2; 54 55 if (*s1 == '\0') 56 return(-1); 57 os1 = s1; 58 c1 = *s1; 59 c2 = *s2; 60 while (LOWER(c1) == LOWER(c2)) { 61 if (c1 == '\0') 62 break; 63 c1 = *++s1; 64 c2 = *++s2; 65 } 66 return(*s1 ? 0 : (*s2 ? (s1 - os1) : (os1 - s1))); 67 } 68 69 static char *ambiguous; /* special return value for command routines */ 70 71 char ** 72 genget(char *name, char **table, int stlen) 73 { 74 char **c, **found; 75 int n; 76 77 if (name == 0) 78 return 0; 79 80 found = 0; 81 for (c = table; *c != 0; c = (char **)((char *)c + stlen)) { 82 if ((n = isprefix(name, *c)) == 0) 83 continue; 84 if (n < 0) /* exact match */ 85 return(c); 86 if (found) 87 return(&ambiguous); 88 found = c; 89 } 90 return(found); 91 } 92 93 /* 94 * Function call version of Ambiguous() 95 */ 96 int 97 Ambiguous(char **s) 98 { 99 return(s == &ambiguous); 100 } 101