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 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 ** 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 110 Ambiguous(void *s) 111 { 112 return ((char **)s == &ambiguous); 113 } 114