Mercurial > hg > ucx / file diff

     1.1 --- a/src/linked_list.c	Mon Sep 27 18:33:30 2021 +0200
     1.2 +++ b/src/linked_list.c	Mon Sep 27 18:50:07 2021 +0200
     1.3 @@ -99,6 +99,9 @@
     1.4      char payload[];
     1.5  };
     1.6  
     1.7 +#define CX_LL_LOC_PREV offsetof(struct cx_linked_list_node, prev)
     1.8 +#define CX_LL_LOC_NEXT offsetof(struct cx_linked_list_node, next)
     1.9 +
    1.10  typedef struct {
    1.11      cx_list_s base;
    1.12      void *begin;
    1.13 @@ -120,8 +123,7 @@
    1.14  
    1.15      int ret = cx_linked_list_add(
    1.16              &ll->begin, &ll->end,
    1.17 -            offsetof(struct cx_linked_list_node, prev),
    1.18 -            offsetof(struct cx_linked_list_node, next),
    1.19 +            CX_LL_LOC_PREV, CX_LL_LOC_NEXT,
    1.20              node
    1.21      );
    1.22      if (ret == 0) {
    1.23 @@ -147,6 +149,17 @@
    1.24      return 0;
    1.25  }
    1.26  
    1.27 +static void *cx_ll_at(cx_list_s *list, size_t index) {
    1.28 +    cx_linked_list *ll = (cx_linked_list *) list;
    1.29 +    struct cx_linked_list_node *node;
    1.30 +    if (index > list->size / 2) {
    1.31 +        node = cx_linked_list_at(ll->begin, 0, CX_LL_LOC_NEXT, index);
    1.32 +    } else {
    1.33 +        node = cx_linked_list_at(ll->end, list->size, CX_LL_LOC_PREV, index);
    1.34 +    }
    1.35 +    return &node->payload;
    1.36 +}
    1.37 +
    1.38  static size_t cx_ll_find(cx_list_s *list, void *elem) {
    1.39      CxListComparator cmp = list->cmpfunc;
    1.40      cx_linked_list *ll = (cx_linked_list *) list;
    1.41 @@ -164,9 +177,8 @@
    1.42  }
    1.43  
    1.44  static void *cx_ll_last(cx_list_s *list) {
    1.45 -    cx_linked_list *linkedList = (cx_linked_list *) list;
    1.46 -    struct cx_linked_list_node *last = cx_linked_list_last(
    1.47 -            NULL, &linkedList->end, offsetof(struct cx_linked_list_node, next));
    1.48 +    cx_linked_list *ll = (cx_linked_list *) list;
    1.49 +    struct cx_linked_list_node *last = cx_linked_list_last(NULL, &ll->end, CX_LL_LOC_NEXT);
    1.50      return &last->payload;
    1.51  }
    1.52  
    1.53 @@ -174,6 +186,7 @@
    1.54          cx_ll_add,
    1.55          cx_ll_insert,
    1.56          cx_ll_remove,
    1.57 +        cx_ll_at,
    1.58          cx_ll_find,
    1.59          cx_ll_last
    1.60  };
    1.61 @@ -190,8 +203,8 @@
    1.62      list->base.capacity = SIZE_MAX;
    1.63  
    1.64      list->begin = NULL;
    1.65 -    list->loc_prev = offsetof(struct cx_linked_list_node, prev);
    1.66 -    list->loc_next = offsetof(struct cx_linked_list_node, next);
    1.67 +    list->loc_prev = CX_LL_LOC_PREV;
    1.68 +    list->loc_next = CX_LL_LOC_NEXT;
    1.69  
    1.70      CxList result = (CxList) list;
    1.71      cxLinkedListRecalculateSize(result);