1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21/* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26#pragma ident "%Z%%M% %I% %E% SMI" 27 28/* 29 * Generic doubly-linked list implementation 30 */ 31 32#include <sys/list.h> 33#include <sys/list_impl.h> 34#include <sys/types.h> 35#include <sys/sysmacros.h> 36#include <sys/debug.h> 37 38#define list_d2l(a, obj) ((list_node_t *)(((char *)obj) + (a)->list_offset)) 39#define list_object(a, node) ((void *)(((char *)node) - (a)->list_offset)) 40#define list_empty(a) ((a)->list_head.list_next == &(a)->list_head) 41 42#define list_insert_after_node(list, node, object) { \ 43 list_node_t *lnew = list_d2l(list, object); \ 44 lnew->list_prev = (node); \ 45 lnew->list_next = (node)->list_next; \ 46 (node)->list_next->list_prev = lnew; \ 47 (node)->list_next = lnew; \ 48} 49 50#define list_insert_before_node(list, node, object) { \ 51 list_node_t *lnew = list_d2l(list, object); \ 52 lnew->list_next = (node); \ 53 lnew->list_prev = (node)->list_prev; \ 54 (node)->list_prev->list_next = lnew; \ 55 (node)->list_prev = lnew; \ 56} 57 58#define list_remove_node(node) \ 59 (node)->list_prev->list_next = (node)->list_next; \ 60 (node)->list_next->list_prev = (node)->list_prev; \ 61 (node)->list_next = (node)->list_prev = NULL 62 63void 64list_create(list_t *list, size_t size, size_t offset) 65{ 66 ASSERT(list); 67 ASSERT(size > 0); 68 ASSERT(size >= offset + sizeof (list_node_t)); 69 70 list->list_size = size; 71 list->list_offset = offset; 72 list->list_head.list_next = list->list_head.list_prev = 73 &list->list_head; 74} 75 76void 77list_destroy(list_t *list) 78{ 79 list_node_t *node = &list->list_head; 80 81 ASSERT(list); 82 ASSERT(list->list_head.list_next == node); 83 ASSERT(list->list_head.list_prev == node); 84 85 node->list_next = node->list_prev = NULL; 86} 87 88void 89list_insert_after(list_t *list, void *object, void *nobject) 90{ 91 if (object == NULL) { 92 list_insert_head(list, nobject); 93 } else { 94 list_node_t *lold = list_d2l(list, object); 95 list_insert_after_node(list, lold, nobject); 96 } 97} 98 99void 100list_insert_before(list_t *list, void *object, void *nobject) 101{ 102 if (object == NULL) { 103 list_insert_tail(list, nobject); 104 } else { 105 list_node_t *lold = list_d2l(list, object); 106 list_insert_before_node(list, lold, nobject); 107 } 108} 109 110void 111list_insert_head(list_t *list, void *object) 112{ 113 list_node_t *lold = &list->list_head; 114 list_insert_after_node(list, lold, object); 115} 116 117void 118list_insert_tail(list_t *list, void *object) 119{ 120 list_node_t *lold = &list->list_head; 121 list_insert_before_node(list, lold, object); 122} 123 124void 125list_remove(list_t *list, void *object) 126{ 127 list_node_t *lold = list_d2l(list, object); 128 ASSERT(!list_empty(list)); 129 ASSERT(lold->list_next != NULL); 130 list_remove_node(lold); 131} 132 133void * 134list_remove_head(list_t *list) 135{ 136 list_node_t *head = list->list_head.list_next; 137 if (head == &list->list_head) 138 return (NULL); 139 list_remove_node(head); 140 return (list_object(list, head)); 141} 142 143void * 144list_remove_tail(list_t *list) 145{ 146 list_node_t *tail = list->list_head.list_prev; 147 if (tail == &list->list_head) 148 return (NULL); 149 list_remove_node(tail); 150 return (list_object(list, tail)); 151} 152 153void * 154list_head(list_t *list) 155{ 156 if (list_empty(list)) 157 return (NULL); 158 return (list_object(list, list->list_head.list_next)); 159} 160 161void * 162list_tail(list_t *list) 163{ 164 if (list_empty(list)) 165 return (NULL); 166 return (list_object(list, list->list_head.list_prev)); 167} 168 169void * 170list_next(list_t *list, void *object) 171{ 172 list_node_t *node = list_d2l(list, object); 173 174 if (node->list_next != &list->list_head) 175 return (list_object(list, node->list_next)); 176 177 return (NULL); 178} 179 180void * 181list_prev(list_t *list, void *object) 182{ 183 list_node_t *node = list_d2l(list, object); 184 185 if (node->list_prev != &list->list_head) 186 return (list_object(list, node->list_prev)); 187 188 return (NULL); 189} 190 191/* 192 * Insert src list after dst list. Empty src list thereafter. 193 */ 194void 195list_move_tail(list_t *dst, list_t *src) 196{ 197 list_node_t *dstnode = &dst->list_head; 198 list_node_t *srcnode = &src->list_head; 199 200 ASSERT(dst->list_size == src->list_size); 201 ASSERT(dst->list_offset == src->list_offset); 202 203 if (list_empty(src)) 204 return; 205 206 dstnode->list_prev->list_next = srcnode->list_next; 207 srcnode->list_next->list_prev = dstnode->list_prev; 208 dstnode->list_prev = srcnode->list_prev; 209 srcnode->list_prev->list_next = dstnode; 210 211 /* empty src list */ 212 srcnode->list_next = srcnode->list_prev = srcnode; 213} 214 215void 216list_link_replace(list_node_t *lold, list_node_t *lnew) 217{ 218 ASSERT(list_link_active(lold)); 219 ASSERT(!list_link_active(lnew)); 220 221 lnew->list_next = lold->list_next; 222 lnew->list_prev = lold->list_prev; 223 lold->list_prev->list_next = lnew; 224 lold->list_next->list_prev = lnew; 225 lold->list_next = lold->list_prev = NULL; 226} 227 228void 229list_link_init(list_node_t *link) 230{ 231 link->list_next = NULL; 232 link->list_prev = NULL; 233} 234 235int 236list_link_active(list_node_t *link) 237{ 238 return (link->list_next != NULL); 239} 240 241int 242list_is_empty(list_t *list) 243{ 244 return (list_empty(list)); 245} 246