lsearch.c revision 7f3a272ae327c647db4caeaea2a3c7af50bd73b5
17f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes/* 27f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * Copyright (c) 1989, 1993 37f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * The Regents of the University of California. All rights reserved. 47f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * 57f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * This code is derived from software contributed to Berkeley by 67f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * Roger L. Snyder. 77f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * 87f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * Redistribution and use in source and binary forms, with or without 97f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * modification, are permitted provided that the following conditions 107f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * are met: 117f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * 1. Redistributions of source code must retain the above copyright 127f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * notice, this list of conditions and the following disclaimer. 137f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * 2. Redistributions in binary form must reproduce the above copyright 147f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * notice, this list of conditions and the following disclaimer in the 157f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * documentation and/or other materials provided with the distribution. 167f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * 3. Neither the name of the University nor the names of its contributors 177f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * may be used to endorse or promote products derived from this software 187f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * without specific prior written permission. 197f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * 207f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 217f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 227f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 237f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 247f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 257f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 267f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 277f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 287f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 297f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 307f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * SUCH DAMAGE. 317f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes */ 327f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 337f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes#include <sys/cdefs.h> 347f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes#if defined(LIBC_SCCS) && !defined(lint) 357f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes#if 0 367f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughesstatic char sccsid[] = "@(#)lsearch.c 8.1 (Berkeley) 6/4/93"; 377f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes#else 387f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes__RCSID("$NetBSD: lsearch.c,v 1.7 2012/06/25 22:32:45 abs Exp $"); 397f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes#endif 407f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes#endif /* LIBC_SCCS and not lint */ 417f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 427f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes#include <sys/types.h> 437f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 447f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes#include <assert.h> 457f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes#include <errno.h> 467f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes#include <string.h> 477f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes#include <search.h> 487f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 497f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughestypedef int (*cmp_fn_t)(const void *, const void *); 507f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughesstatic void *linear_base(const void *, void *, size_t *, size_t, 517f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes cmp_fn_t, int); 527f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 537f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughesvoid * 547f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hugheslsearch(const void *key, void *base, size_t *nelp, size_t width, 557f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes cmp_fn_t compar) 567f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes{ 577f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 587f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes _DIAGASSERT(key != NULL); 597f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes _DIAGASSERT(base != NULL); 607f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes _DIAGASSERT(compar != NULL); 617f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 627f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes return(linear_base(key, base, nelp, width, compar, 1)); 637f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes} 647f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 657f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughesvoid * 667f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hugheslfind(const void *key, const void *base, size_t *nelp, size_t width, 677f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes cmp_fn_t compar) 687f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes{ 697f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 707f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes _DIAGASSERT(key != NULL); 717f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes _DIAGASSERT(base != NULL); 727f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes _DIAGASSERT(compar != NULL); 737f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 747f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes return(linear_base(key, __UNCONST(base), nelp, width, compar, 0)); 757f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes} 767f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 777f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughesstatic void * 787f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hugheslinear_base(const void *key, void *base, size_t *nelp, size_t width, 797f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes cmp_fn_t compar, int add_flag) 807f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes{ 817f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes char *element, *end; 827f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 837f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes _DIAGASSERT(key != NULL); 847f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes _DIAGASSERT(base != NULL); 857f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes _DIAGASSERT(compar != NULL); 867f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 877f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes end = (char *)base + *nelp * width; 887f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes for (element = (char *)base; element < end; element += width) 897f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes if (!compar(element, key)) /* key found */ 907f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes return element; 917f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 927f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes if (!add_flag) /* key not found */ 937f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes return(NULL); 947f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes 957f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes /* 967f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * The UNIX System User's Manual, 1986 edition claims that 977f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * a NULL pointer is returned by lsearch with errno set 987f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * appropriately, if there is not enough room in the table 997f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * to add a new item. This can't be done as none of these 1007f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * routines have any method of determining the size of the 1017f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * table. This comment isn't in the 1986-87 System V 1027f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes * manual. 1037f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes */ 1047f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes ++*nelp; 1057f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes memcpy(end, key, width); 1067f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes return end; 1077f3a272ae327c647db4caeaea2a3c7af50bd73b5Elliott Hughes} 108