libtu/dlist.h

   1 /*
   2  * libtu/common.h
   3  *
   4  * Copyright (c) Tuomo Valkonen 1999-2005.
   5  *
   6  * You may distribute and modify this library under the terms of either
   7  * the Clarified Artistic License or the GNU LGPL, version 2.1 or later.
   8  */
   9
  10 #ifndef LIBTU_DLIST_H
  11 #define LIBTU_DLIST_H
  12
  13
  14 /*{{{ Linking */
  15
  16
  17 #define LINK_ITEM(LIST, ITEM, NEXT, PREV) \
  18     (ITEM)->NEXT=NULL;                    \
  19     if((LIST)==NULL){                     \
  20         (LIST)=(ITEM);                    \
  21         (ITEM)->PREV=(ITEM);              \
  22     }else{                                \
  23         (ITEM)->PREV=(LIST)->PREV;        \
  24         (ITEM)->PREV->NEXT=(ITEM);        \
  25         (LIST)->PREV=(ITEM);              \
  26     }
  27
  28
  29 #define LINK_ITEM_FIRST(LIST, ITEM, NEXT, PREV) \
  30     (ITEM)->NEXT=(LIST);                        \
  31     if((LIST)==NULL){                           \
  32         (ITEM)->PREV=(ITEM);                    \
  33     }else{                                      \
  34         (ITEM)->PREV=(LIST)->PREV;              \
  35         (LIST)->PREV=(ITEM);                    \
  36     }                                           \
  37     (LIST)=(ITEM);
  38
  39
  40 #define LINK_ITEM_LAST LINK_ITEM
  41
  42
  43 #define LINK_ITEM_BEFORE(LIST, BEFORE, ITEM, NEXT, PREV) \
  44     (ITEM)->NEXT=(BEFORE);                               \
  45     (ITEM)->PREV=(BEFORE)->PREV;                         \
  46     (BEFORE)->PREV=(ITEM);                               \
  47     if((BEFORE)==(LIST))                                 \
  48         (LIST)=(ITEM);                                   \
  49     else                                                 \
  50         (ITEM)->PREV->NEXT=(ITEM)
  51
  52
  53 #define LINK_ITEM_AFTER(LIST, AFTER, ITEM, NEXT, PREV) \
  54     (ITEM)->NEXT=(AFTER)->NEXT;                        \
  55     (ITEM)->PREV=(AFTER);                              \
  56     (AFTER)->NEXT=(ITEM);                              \
  57     if((ITEM)->NEXT==NULL)                             \
  58         (LIST)->PREV=(ITEM);                           \
  59     else                                               \
  60         (ITEM)->NEXT->PREV=ITEM;
  61
  62
  63 #define UNLINK_ITEM(LIST, ITEM, NEXT, PREV)  \
  64     if((ITEM)->PREV!=NULL){                  \
  65         if((ITEM)==(LIST)){                  \
  66             (LIST)=(ITEM)->NEXT;             \
  67             if((LIST)!=NULL)                 \
  68                 (LIST)->PREV=(ITEM)->PREV;   \
  69         }else if((ITEM)->NEXT==NULL){        \
  70             (ITEM)->PREV->NEXT=NULL;         \
  71             (LIST)->PREV=(ITEM)->PREV;       \
  72         }else{                               \
  73             (ITEM)->PREV->NEXT=(ITEM)->NEXT; \
  74             (ITEM)->NEXT->PREV=(ITEM)->PREV; \
  75         }                                    \
  76     }                                        \
  77     (ITEM)->NEXT=NULL;                       \
  78     (ITEM)->PREV=NULL;
  79
  80
  81 /*}}}*/
  82
  83
  84 /*{{{ Iteration */
  85
  86
  87 #define LIST_FIRST(LIST, NEXT, PREV) \
  88     (LIST)
  89 #define LIST_LAST(LIST, NEXT, PREV) \
  90     ((LIST)==NULL ? NULL : LIST_PREV_WRAP(LIST, LIST, NEXT, PREV))
  91 #define LIST_NEXT(LIST, REG, NEXT, PREV) \
  92     ((REG)->NEXT)
  93 #define LIST_PREV(LIST, REG, NEXT, PREV) \
  94     ((REG)->PREV->NEXT ? (REG)->PREV : NULL)
  95 #define LIST_NEXT_WRAP(LIST, REG, NEXT, PREV) \
  96     (((REG) && (REG)->NEXT) ? (REG)->NEXT : (LIST))
  97 #define LIST_PREV_WRAP(LIST, REG, NEXT, PREV) \
  98     ((REG) ? (REG)->PREV : (LIST))
  99
 100 #define LIST_FOR_ALL(LIST, NODE, NEXT, PREV) \
 101     for(NODE=LIST; NODE!=NULL; NODE=(NODE)->NEXT)
 102
 103 #define LIST_FOR_ALL_REV(LIST, NODE, NEXT, PREV)     \
 104     for(NODE=((LIST)==NULL ? NULL : (LIST)->PREV);   \
 105         NODE!=NULL;                                  \
 106         NODE=((NODE)==(LIST) ? NULL : (NODE)->PREV))
 107
 108 #define LIST_FOR_ALL_W_NEXT(LIST, NODE, NXT, NEXT, PREV)  \
 109     for(NODE=LL, NXT=(NODE==NULL ? NULL : (NODE)->NEXT);  \
 110         NODE!=NULL;                                       \
 111         NODE=NXT, NXT=(NODE==NULL ? NULL : (NODE)->NEXT))
 112
 113 #define LIST_FOR_ALL_W_NEXT_REV(LIST, NODE, NXT, NEXT, PREV) \
 114     for(NODE=((LIST)==NULL ? NULL : (LIST)->PREV),           \
 115          NXT=((NODE)==(LIST) ? NULL : (NODE)->PREV);         \
 116         NODE!=NULL;                                          \
 117         NODE=NXT,                                            \
 118          NXT=((NODE)==(LIST) ? NULL : (NODE)->PREV))
 119
 120
 121 /*}}}*/
 122
 123
 124 #endif /* LIBTU_DLIST_H */