contrib/jemalloc/include/jemalloc/internal/qr.h

   1 /* Ring definitions. */
   2 #define qr(a_type)                                                      \
   3 struct {                                                                \
   4         a_type  *qre_next;                                              \
   5         a_type  *qre_prev;                                              \
   6 }
   7
   8 /* Ring functions. */
   9 #define qr_new(a_qr, a_field) do {                                      \
  10         (a_qr)->a_field.qre_next = (a_qr);                              \
  11         (a_qr)->a_field.qre_prev = (a_qr);                              \
  12 } while (0)
  13
  14 #define qr_next(a_qr, a_field) ((a_qr)->a_field.qre_next)
  15
  16 #define qr_prev(a_qr, a_field) ((a_qr)->a_field.qre_prev)
  17
  18 #define qr_before_insert(a_qrelm, a_qr, a_field) do {                   \
  19         (a_qr)->a_field.qre_prev = (a_qrelm)->a_field.qre_prev;         \
  20         (a_qr)->a_field.qre_next = (a_qrelm);                           \
  21         (a_qr)->a_field.qre_prev->a_field.qre_next = (a_qr);            \
  22         (a_qrelm)->a_field.qre_prev = (a_qr);                           \
  23 } while (0)
  24
  25 #define qr_after_insert(a_qrelm, a_qr, a_field)                         \
  26     do                                                                  \
  27     {                                                                   \
  28         (a_qr)->a_field.qre_next = (a_qrelm)->a_field.qre_next;         \
  29         (a_qr)->a_field.qre_prev = (a_qrelm);                           \
  30         (a_qr)->a_field.qre_next->a_field.qre_prev = (a_qr);            \
  31         (a_qrelm)->a_field.qre_next = (a_qr);                           \
  32     } while (0)
  33
  34 #define qr_meld(a_qr_a, a_qr_b, a_field) do {                           \
  35         void *t;                                                        \
  36         (a_qr_a)->a_field.qre_prev->a_field.qre_next = (a_qr_b);        \
  37         (a_qr_b)->a_field.qre_prev->a_field.qre_next = (a_qr_a);        \
  38         t = (a_qr_a)->a_field.qre_prev;                                 \
  39         (a_qr_a)->a_field.qre_prev = (a_qr_b)->a_field.qre_prev;        \
  40         (a_qr_b)->a_field.qre_prev = t;                                 \
  41 } while (0)
  42
  43 /* qr_meld() and qr_split() are functionally equivalent, so there's no need to
  44  * have two copies of the code. */
  45 #define qr_split(a_qr_a, a_qr_b, a_field)                               \
  46         qr_meld((a_qr_a), (a_qr_b), a_field)
  47
  48 #define qr_remove(a_qr, a_field) do {                                   \
  49         (a_qr)->a_field.qre_prev->a_field.qre_next                      \
  50             = (a_qr)->a_field.qre_next;                                 \
  51         (a_qr)->a_field.qre_next->a_field.qre_prev                      \
  52             = (a_qr)->a_field.qre_prev;                                 \
  53         (a_qr)->a_field.qre_next = (a_qr);                              \
  54         (a_qr)->a_field.qre_prev = (a_qr);                              \
  55 } while (0)
  56
  57 #define qr_foreach(var, a_qr, a_field)                                  \
  58         for ((var) = (a_qr);                                            \
  59             (var) != NULL;                                              \
  60             (var) = (((var)->a_field.qre_next != (a_qr))                \
  61             ? (var)->a_field.qre_next : NULL))
  62
  63 #define qr_reverse_foreach(var, a_qr, a_field)                          \
  64         for ((var) = ((a_qr) != NULL) ? qr_prev(a_qr, a_field) : NULL;  \
  65             (var) != NULL;                                              \
  66             (var) = (((var) != (a_qr))                                  \
  67             ? (var)->a_field.qre_prev : NULL))