include/reactos/wine/list.h

   1 /*
   2  * Linked lists support
   3  *
   4  * Copyright (C) 2002 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #ifndef __WINE_SERVER_LIST_H
  22 #define __WINE_SERVER_LIST_H
  23
  24 #ifdef __cplusplus
  25 #define __WINE_SERVER_LIST_INLINE inline
  26 #else
  27 #if defined(__GNUC__)
  28 #define __WINE_SERVER_LIST_INLINE extern __inline__ __attribute__((__always_inline__,__gnu_inline__))
  29 #elif defined(_MSC_VER)
  30 #define __WINE_SERVER_LIST_INLINE __inline
  31 #else
  32 #define __WINE_SERVER_LIST_INLINE static
  33 #endif
  34 #endif
  35
  36 struct list
  37 {
  38     struct list *next;
  39     struct list *prev;
  40 };
  41
  42 /* Define a list like so:
  43  *
  44  *   struct gadget
  45  *   {
  46  *       struct list  entry;   <-- doesn't have to be the first item in the struct
  47  *       int          a, b;
  48  *   };
  49  *
  50  *   static struct list global_gadgets = LIST_INIT( global_gadgets );
  51  *
  52  * or
  53  *
  54  *   struct some_global_thing
  55  *   {
  56  *       struct list gadgets;
  57  *   };
  58  *
  59  *   list_init( &some_global_thing->gadgets );
  60  *
  61  * Manipulate it like this:
  62  *
  63  *   list_add_head( &global_gadgets, &new_gadget->entry );
  64  *   list_remove( &new_gadget->entry );
  65  *   list_add_after( &some_random_gadget->entry, &new_gadget->entry );
  66  *
  67  * And to iterate over it:
  68  *
  69  *   struct gadget *gadget;
  70  *   LIST_FOR_EACH_ENTRY( gadget, &global_gadgets, struct gadget, entry )
  71  *   {
  72  *       ...
  73  *   }
  74  *
  75  */
  76
  77 /* add an element after the specified one */
  78 __WINE_SERVER_LIST_INLINE void list_add_after( struct list *elem, struct list *to_add )
  79 {
  80     to_add->next = elem->next;
  81     to_add->prev = elem;
  82     elem->next->prev = to_add;
  83     elem->next = to_add;
  84 }
  85
  86 /* add an element before the specified one */
  87 __WINE_SERVER_LIST_INLINE void list_add_before( struct list *elem, struct list *to_add )
  88 {
  89     to_add->next = elem;
  90     to_add->prev = elem->prev;
  91     elem->prev->next = to_add;
  92     elem->prev = to_add;
  93 }
  94
  95 /* add element at the head of the list */
  96 __WINE_SERVER_LIST_INLINE void list_add_head( struct list *list, struct list *elem )
  97 {
  98     list_add_after( list, elem );
  99 }
 100
 101 /* add element at the tail of the list */
 102 __WINE_SERVER_LIST_INLINE void list_add_tail( struct list *list, struct list *elem )
 103 {
 104     list_add_before( list, elem );
 105 }
 106
 107 /* remove an element from its list */
 108 __WINE_SERVER_LIST_INLINE void list_remove( struct list *elem )
 109 {
 110     elem->next->prev = elem->prev;
 111     elem->prev->next = elem->next;
 112 }
 113
 114 /* get the next element */
 115 __WINE_SERVER_LIST_INLINE struct list *list_next( const struct list *list, const struct list *elem )
 116 {
 117     struct list *ret = elem->next;
 118     if (elem->next == list) ret = NULL;
 119     return ret;
 120 }
 121
 122 /* get the previous element */
 123 __WINE_SERVER_LIST_INLINE struct list *list_prev( const struct list *list, const struct list *elem )
 124 {
 125     struct list *ret = elem->prev;
 126     if (elem->prev == list) ret = NULL;
 127     return ret;
 128 }
 129
 130 /* get the first element */
 131 __WINE_SERVER_LIST_INLINE struct list *list_head( const struct list *list )
 132 {
 133     return list_next( list, list );
 134 }
 135
 136 /* get the last element */
 137 __WINE_SERVER_LIST_INLINE struct list *list_tail( const struct list *list )
 138 {
 139     return list_prev( list, list );
 140 }
 141
 142 /* check if a list is empty */
 143 __WINE_SERVER_LIST_INLINE int list_empty( const struct list *list )
 144 {
 145     return list->next == list;
 146 }
 147
 148 /* initialize a list */
 149 __WINE_SERVER_LIST_INLINE void list_init( struct list *list )
 150 {
 151     list->next = list->prev = list;
 152 }
 153
 154 /* count the elements of a list */
 155 __WINE_SERVER_LIST_INLINE unsigned int list_count( const struct list *list )
 156 {
 157     unsigned count = 0;
 158     const struct list *ptr;
 159     for (ptr = list->next; ptr != list; ptr = ptr->next) count++;
 160     return count;
 161 }
 162
 163 /* move all elements from src to the tail of dst */
 164 __WINE_SERVER_LIST_INLINE void list_move_tail( struct list *dst, struct list *src )
 165 {
 166     if (list_empty(src)) return;
 167
 168     dst->prev->next = src->next;
 169     src->next->prev = dst->prev;
 170     dst->prev = src->prev;
 171     src->prev->next = dst;
 172     list_init(src);
 173 }
 174
 175 /* move all elements from src to the head of dst */
 176 __WINE_SERVER_LIST_INLINE void list_move_head( struct list *dst, struct list *src )
 177 {
 178     if (list_empty(src)) return;
 179
 180     dst->next->prev = src->prev;
 181     src->prev->next = dst->next;
 182     dst->next = src->next;
 183     src->next->prev = dst;
 184     list_init(src);
 185 }
 186
 187 /* iterate through the list */
 188 #define LIST_FOR_EACH(cursor,list) \
 189     for ((cursor) = (list)->next; (cursor) != (list); (cursor) = (cursor)->next)
 190
 191 /* iterate through the list, with safety against removal */
 192 #define LIST_FOR_EACH_SAFE(cursor, cursor2, list) \
 193     for ((cursor) = (list)->next, (cursor2) = (cursor)->next; \
 194          (cursor) != (list); \
 195          (cursor) = (cursor2), (cursor2) = (cursor)->next)
 196
 197 /* iterate through the list using a list entry */
 198 #define LIST_FOR_EACH_ENTRY(elem, list, type, field) \
 199     for ((elem) = LIST_ENTRY((list)->next, type, field); \
 200          &(elem)->field != (list); \
 201          (elem) = LIST_ENTRY((elem)->field.next, type, field))
 202
 203 /* iterate through the list using a list entry, with safety against removal */
 204 #define LIST_FOR_EACH_ENTRY_SAFE(cursor, cursor2, list, type, field) \
 205     for ((cursor) = LIST_ENTRY((list)->next, type, field), \
 206          (cursor2) = LIST_ENTRY((cursor)->field.next, type, field); \
 207          &(cursor)->field != (list); \
 208          (cursor) = (cursor2), \
 209          (cursor2) = LIST_ENTRY((cursor)->field.next, type, field))
 210
 211 /* iterate through the list in reverse order */
 212 #define LIST_FOR_EACH_REV(cursor,list) \
 213     for ((cursor) = (list)->prev; (cursor) != (list); (cursor) = (cursor)->prev)
 214
 215 /* iterate through the list in reverse order, with safety against removal */
 216 #define LIST_FOR_EACH_SAFE_REV(cursor, cursor2, list) \
 217     for ((cursor) = (list)->prev, (cursor2) = (cursor)->prev; \
 218          (cursor) != (list); \
 219          (cursor) = (cursor2), (cursor2) = (cursor)->prev)
 220
 221 /* iterate through the list in reverse order using a list entry */
 222 #define LIST_FOR_EACH_ENTRY_REV(elem, list, type, field) \
 223     for ((elem) = LIST_ENTRY((list)->prev, type, field); \
 224          &(elem)->field != (list); \
 225          (elem) = LIST_ENTRY((elem)->field.prev, type, field))
 226
 227 /* iterate through the list in reverse order using a list entry, with safety against removal */
 228 #define LIST_FOR_EACH_ENTRY_SAFE_REV(cursor, cursor2, list, type, field) \
 229     for ((cursor) = LIST_ENTRY((list)->prev, type, field), \
 230          (cursor2) = LIST_ENTRY((cursor)->field.prev, type, field); \
 231          &(cursor)->field != (list); \
 232          (cursor) = (cursor2), \
 233          (cursor2) = LIST_ENTRY((cursor)->field.prev, type, field))
 234
 235 /* macros for statically initialized lists */
 236 #define LIST_INIT(list)  { &(list), &(list) }
 237
 238 /* get pointer to object containing list element */
 239 #ifdef _WIN64
 240 #define LIST_ENTRY(elem, type, field) \
 241     ((type *)((char *)(elem) - (unsigned long long)(&((type *)0)->field)))
 242 #else
 243 #define LIST_ENTRY(elem, type, field) \
 244     ((type *)((char *)(elem) - (unsigned long)(&((type *)0)->field)))
 245 #endif
 246
 247 #endif  /* __WINE_SERVER_LIST_H */