Home | History | Annotate | Line # | Download | only in src 
      1 /*
      2 Copyright (c) 2007-2009, Troy D. Hanson
      3 All rights reserved.
      4 
      5 Redistribution and use in source and binary forms, with or without
      6 modification, are permitted provided that the following conditions are met:
      7 
      8     * Redistributions of source code must retain the above copyright
      9       notice, this list of conditions and the following disclaimer.
     10 
     11 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
     12 IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     13 TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
     14 PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
     15 OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     16 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     17 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     18 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
     19 LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
     20 NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
     21 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     22 */
     23 
     24 #ifndef UTLIST_H
     25 #define UTLIST_H
     26 
     27 #define UTLIST_VERSION 1.7
     28 
     29 /* From: http://uthash.sourceforge.net/utlist.html */
     30 /*
     31  * This file contains macros to manipulate singly and doubly-linked lists.
     32  *
     33  * 1. LL_ macros:  singly-linked lists.
     34  * 2. DL_ macros:  doubly-linked lists.
     35  * 3. CDL_ macros: circular doubly-linked lists.
     36  *
     37  * To use singly-linked lists, your structure must have a "next" pointer.
     38  * To use doubly-linked lists, your structure must "prev" and "next" pointers.
     39  * Either way, the pointer to the head of the list must be initialized to NULL.
     40  *
     41  * ----------------.EXAMPLE -------------------------
     42  * struct item {
     43  *      int id;
     44  *      struct item *prev, *next;
     45  * }
     46  *
     47  * struct item *list = NULL:
     48  *
     49  * int main() {
     50  *      struct item *item;
     51  *      ... allocate and populate item ...
     52  *      DL_APPEND(list, item);
     53  * }
     54  * --------------------------------------------------
     55  *
     56  * For doubly-linked lists, the append and delete macros are O(1)
     57  * For singly-linked lists, append and delete are O(n) but prepend is O(1)
     58  * The sort macro is O(n log(n)) for all types of single/double/circular lists.
     59  */
     60 
     61 
     62 /******************************************************************************
     63  * doubly linked list macros (non-circular)                                   *
     64  *****************************************************************************/
     65 #define DL_PREPEND(head,add)                                                     \
     66 do {                                                                             \
     67  (add)->next = head;                                                             \
     68  if (head) {                                                                     \
     69    (add)->prev = (head)->prev;                                                   \
     70    (head)->prev = (add);                                                         \
     71  } else {                                                                        \
     72    (add)->prev = (add);                                                          \
     73  }                                                                               \
     74  (head) = (add);                                                                 \
     75 } while (0)
     76 
     77 #define DL_APPEND(head,add)                                                      \
     78 do {                                                                             \
     79   if (head) {                                                                    \
     80       (add)->prev = (head)->prev;                                                \
     81       (head)->prev->next = (add);                                                \
     82       (head)->prev = (add);                                                      \
     83       (add)->next = NULL;                                                        \
     84   } else {                                                                       \
     85       (head)=(add);                                                              \
     86       (head)->prev = (head);                                                     \
     87       (head)->next = NULL;                                                       \
     88   }                                                                              \
     89 } while (0)
     90 
     91 #define DL_DELETE(head,del)                                                      \
     92 do {                                                                             \
     93   if ((del)->prev == (del)) {                                                    \
     94       (head)=NULL;                                                               \
     95   } else if ((del)==(head)) {                                                    \
     96       (del)->next->prev = (del)->prev;                                           \
     97       (head) = (del)->next;                                                      \
     98   } else {                                                                       \
     99       (del)->prev->next = (del)->next;                                           \
    100       if ((del)->next) {                                                         \
    101           (del)->next->prev = (del)->prev;                                       \
    102       } else {                                                                   \
    103           (head)->prev = (del)->prev;                                            \
    104       }                                                                          \
    105   }                                                                              \
    106 } while (0)
    107 
    108 
    109 #define DL_FOREACH(head,el)                                                      \
    110     for(el=head;el;el=el->next)
    111 
    112 #define DL_FOREACH_SAFE(head,el,tmp)                                             \
    113     for(el=head,tmp=el->next;el;el=tmp,tmp=(el) ? (el->next) : NULL)
    114 
    115 #endif /* UTLIST_H */
    116 
    117