1 /************************************************************************** 2 * 3 * Copyright 2006 Tungsten Graphics, Inc., Bismarck, ND. USA. 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 17 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, 18 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 19 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 20 * USE OR OTHER DEALINGS IN THE SOFTWARE. 21 * 22 * The above copyright notice and this permission notice (including the 23 * next paragraph) shall be included in all copies or substantial portions 24 * of the Software. 25 * 26 **************************************************************************/ 27 28 /** 29 * \file 30 * List macros heavily inspired by the Linux kernel 31 * list handling. No list looping yet. 32 * 33 * Is not threadsafe, so common operations need to 34 * be protected using an external mutex. 35 */ 36 37 #ifndef _U_DOUBLE_LIST_H_ 38 #define _U_DOUBLE_LIST_H_ 39 40 41 #include <stddef.h> 42 #include "pipe/p_compiler.h" 43 44 45 struct list_head 46 { 47 struct list_head *prev; 48 struct list_head *next; 49 }; 50 51 static INLINE void list_inithead(struct list_head *item) 52 { 53 item->prev = item; 54 item->next = item; 55 } 56 57 static INLINE void list_add(struct list_head *item, struct list_head *list) 58 { 59 item->prev = list; 60 item->next = list->next; 61 list->next->prev = item; 62 list->next = item; 63 } 64 65 static INLINE void list_addtail(struct list_head *item, struct list_head *list) 66 { 67 item->next = list; 68 item->prev = list->prev; 69 list->prev->next = item; 70 list->prev = item; 71 } 72 73 static INLINE void list_replace(struct list_head *from, struct list_head *to) 74 { 75 to->prev = from->prev; 76 to->next = from->next; 77 from->next->prev = to; 78 from->prev->next = to; 79 } 80 81 static INLINE void list_del(struct list_head *item) 82 { 83 item->prev->next = item->next; 84 item->next->prev = item->prev; 85 item->prev = item->next = NULL; 86 } 87 88 static INLINE void list_delinit(struct list_head *item) 89 { 90 item->prev->next = item->next; 91 item->next->prev = item->prev; 92 item->next = item; 93 item->prev = item; 94 } 95 96 #define LIST_INITHEAD(__item) list_inithead(__item) 97 #define LIST_ADD(__item, __list) list_add(__item, __list) 98 #define LIST_ADDTAIL(__item, __list) list_addtail(__item, __list) 99 #define LIST_REPLACE(__from, __to) list_replace(__from, __to) 100 #define LIST_DEL(__item) list_del(__item) 101 #define LIST_DELINIT(__item) list_delinit(__item) 102 103 #define LIST_ENTRY(__type, __item, __field) \ 104 ((__type *)(((char *)(__item)) - offsetof(__type, __field))) 105 106 #define LIST_IS_EMPTY(__list) \ 107 ((__list)->next == (__list)) 108 109 /** 110 * Cast from a pointer to a member of a struct back to the containing struct. 111 * 112 * 'sample' MUST be initialized, or else the result is undefined! 113 */ 114 #ifndef container_of 115 #define container_of(ptr, sample, member) \ 116 (void *)((char *)(ptr) \ 117 - ((char *)&(sample)->member - (char *)(sample))) 118 #endif 119 120 #define LIST_FOR_EACH_ENTRY(pos, head, member) \ 121 for (pos = NULL, pos = container_of((head)->next, pos, member); \ 122 &pos->member != (head); \ 123 pos = container_of(pos->member.next, pos, member)) 124 125 #define LIST_FOR_EACH_ENTRY_SAFE(pos, storage, head, member) \ 126 for (pos = NULL, pos = container_of((head)->next, pos, member), \ 127 storage = container_of(pos->member.next, pos, member); \ 128 &pos->member != (head); \ 129 pos = storage, storage = container_of(storage->member.next, storage, member)) 130 131 #define LIST_FOR_EACH_ENTRY_SAFE_REV(pos, storage, head, member) \ 132 for (pos = NULL, pos = container_of((head)->prev, pos, member), \ 133 storage = container_of(pos->member.prev, pos, member); \ 134 &pos->member != (head); \ 135 pos = storage, storage = container_of(storage->member.prev, storage, member)) 136 137 #define LIST_FOR_EACH_ENTRY_FROM(pos, start, head, member) \ 138 for (pos = NULL, pos = container_of((start), pos, member); \ 139 &pos->member != (head); \ 140 pos = container_of(pos->member.next, pos, member)) 141 142 #define LIST_FOR_EACH_ENTRY_FROM_REV(pos, start, head, member) \ 143 for (pos = NULL, pos = container_of((start), pos, member); \ 144 &pos->member != (head); \ 145 pos = container_of(pos->member.prev, pos, member)) 146 147 #endif /*_U_DOUBLE_LIST_H_*/ 148
