1 /* 2 * Initial implementation: 3 * Copyright (c) 2002 Robert Drehmel 4 * All rights reserved. 5 * 6 * As long as the above copyright statement and this notice remain 7 * unchanged, you can do what ever you want with this file. 8 * 9 * $DragonFly: src/lib/libc/stdlib/lsearch.c,v 1.1 2008/05/19 10:06:34 corecode Exp $ 10 */ 11 #include <sys/types.h> 12 #include <sys/cdefs.h> 13 14 #define _SEARCH_PRIVATE 15 #include <search.h> 16 #include <stdint.h> /* for uint8_t */ 17 #include <stdlib.h> /* for NULL */ 18 #include <string.h> /* for memcpy() prototype */ 19 20 static void *lwork(const void *, const void *, size_t *, size_t, 21 int (*)(const void *, const void *), int); 22 23 void *lsearch(const void *key, void *base, size_t *nelp, size_t width, 24 int (*compar)(const void *, const void *)) 25 { 26 27 return (lwork(key, base, nelp, width, compar, 1)); 28 } 29 30 void *lfind(const void *key, const void *base, size_t *nelp, size_t width, 31 int (*compar)(const void *, const void *)) 32 { 33 34 return (lwork(key, base, nelp, width, compar, 0)); 35 } 36 37 static void * 38 lwork(const void *key, const void *base, size_t *nelp, size_t width, 39 int (*compar)(const void *, const void *), int addelem) 40 { 41 uint8_t *ep, *endp; 42 43 /* 44 * Cast to an integer value first to avoid the warning for removing 45 * 'const' via a cast. 46 */ 47 ep = (uint8_t *)(uintptr_t)base; 48 for (endp = (uint8_t *)(ep + width * *nelp); ep < endp; ep += width) { 49 if (compar(key, ep) == 0) 50 return (ep); 51 } 52 53 /* lfind() shall return when the key was not found. */ 54 if (!addelem) 55 return (NULL); 56 57 /* 58 * lsearch() adds the key to the end of the table and increments 59 * the number of elements. 60 */ 61 memcpy(endp, key, width); 62 ++*nelp; 63 64 return (endp); 65 } 66