1 /* $OpenBSD: lsearch.c,v 1.7 2021/12/08 22:06:28 cheloha Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Roger L. Snyder. 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. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/types.h> 36 #include <string.h> 37 #include <search.h> 38 39 typedef int (*cmp_fn_t)(const void *, const void *); 40 41 void * 42 lsearch(const void *key, void *base, size_t *nelp, size_t width, 43 cmp_fn_t compar) 44 { 45 void *element = lfind(key, base, nelp, width, compar); 46 47 /* 48 * Use memmove(3) to ensure the key is copied cleanly into the 49 * array, even if the key overlaps with the end of the array. 50 */ 51 if (element == NULL) { 52 element = memmove((char *)base + *nelp * width, key, width); 53 *nelp += 1; 54 } 55 return element; 56 } 57 58 void * 59 lfind(const void *key, const void *base, size_t *nelp, size_t width, 60 cmp_fn_t compar) 61 { 62 const char *element, *end; 63 64 end = (const char *)base + *nelp * width; 65 for (element = base; element < end; element += width) 66 if (!compar(key, element)) /* key found */ 67 return((void *)element); 68 return NULL; 69 } 70 DEF_WEAK(lfind); 71