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

   1 #ifndef JEMALLOC_INTERNAL_QR_H
   2 #define JEMALLOC_INTERNAL_QR_H
   3
   4 /* Ring definitions. */
   5 #define qr(a_type)                                                      \
   6 struct {                                                                \
   7         a_type  *qre_next;                                              \
   8         a_type  *qre_prev;                                              \
   9 }
  10
  11 /* Ring functions. */
  12 #define qr_new(a_qr, a_field) do {                                      \
  13         (a_qr)->a_field.qre_next = (a_qr);                              \
  14         (a_qr)->a_field.qre_prev = (a_qr);                              \
  15 } while (0)
  16
  17 #define qr_next(a_qr, a_field) ((a_qr)->a_field.qre_next)
  18
  19 #define qr_prev(a_qr, a_field) ((a_qr)->a_field.qre_prev)
  20
  21 #define qr_before_insert(a_qrelm, a_qr, a_field) do {                   \
  22         (a_qr)->a_field.qre_prev = (a_qrelm)->a_field.qre_prev;         \
  23         (a_qr)->a_field.qre_next = (a_qrelm);                           \
  24         (a_qr)->a_field.qre_prev->a_field.qre_next = (a_qr);            \
  25         (a_qrelm)->a_field.qre_prev = (a_qr);                           \
  26 } while (0)
  27
  28 #define qr_after_insert(a_qrelm, a_qr, a_field) do {                    \
  29         (a_qr)->a_field.qre_next = (a_qrelm)->a_field.qre_next;         \
  30         (a_qr)->a_field.qre_prev = (a_qrelm);                           \
  31         (a_qr)->a_field.qre_next->a_field.qre_prev = (a_qr);            \
  32         (a_qrelm)->a_field.qre_next = (a_qr);                           \
  33 } while (0)
  34
  35 #define qr_meld(a_qr_a, a_qr_b, a_type, a_field) do {                   \
  36         a_type *t;                                                      \
  37         (a_qr_a)->a_field.qre_prev->a_field.qre_next = (a_qr_b);        \
  38         (a_qr_b)->a_field.qre_prev->a_field.qre_next = (a_qr_a);        \
  39         t = (a_qr_a)->a_field.qre_prev;                                 \
  40         (a_qr_a)->a_field.qre_prev = (a_qr_b)->a_field.qre_prev;        \
  41         (a_qr_b)->a_field.qre_prev = t;                                 \
  42 } while (0)
  43
  44 /*
  45  * qr_meld() and qr_split() are functionally equivalent, so there's no need to
  46  * have two copies of the code.
  47  */
  48 #define qr_split(a_qr_a, a_qr_b, a_type, a_field)                       \
  49         qr_meld((a_qr_a), (a_qr_b), a_type, a_field)
  50
  51 #define qr_remove(a_qr, a_field) do {                                   \
  52         (a_qr)->a_field.qre_prev->a_field.qre_next                      \
  53             = (a_qr)->a_field.qre_next;                                 \
  54         (a_qr)->a_field.qre_next->a_field.qre_prev                      \
  55             = (a_qr)->a_field.qre_prev;                                 \
  56         (a_qr)->a_field.qre_next = (a_qr);                              \
  57         (a_qr)->a_field.qre_prev = (a_qr);                              \
  58 } while (0)
  59
  60 #define qr_foreach(var, a_qr, a_field)                                  \
  61         for ((var) = (a_qr);                                            \
  62             (var) != NULL;                                              \
  63             (var) = (((var)->a_field.qre_next != (a_qr))                \
  64             ? (var)->a_field.qre_next : NULL))
  65
  66 #define qr_reverse_foreach(var, a_qr, a_field)                          \
  67         for ((var) = ((a_qr) != NULL) ? qr_prev(a_qr, a_field) : NULL;  \
  68             (var) != NULL;                                              \
  69             (var) = (((var) != (a_qr))                                  \
  70             ? (var)->a_field.qre_prev : NULL))
  71
  72 #endif /* JEMALLOC_INTERNAL_QR_H */