qr.rar_No There There

/* Ring definitions. */ #define qr(a_type) \ struct { \ a_type *qre_next; \ a_type *qre_prev; \ } /* Ring functions. */ #define qr_new(a_qr, a_field) do { \ (a_qr)->a_field.qre_next = (a_qr); \ (a_qr)->a_field.qre_prev = (a_qr); \ } while (0) #define qr_next(a_qr, a_field) ((a_qr)->a_field.qre_next) #define qr_prev(a_qr, a_field) ((a_qr)->a_field.qre_prev) #define qr_before_insert(a_qrelm, a_qr, a_field) do { \ (a_qr)->a_field.qre_prev = (a_qrelm)->a_field.qre_prev; \ (a_qr)->a_field.qre_next = (a_qrelm); \ (a_qr)->a_field.qre_prev->a_field.qre_next = (a_qr); \ (a_qrelm)->a_field.qre_prev = (a_qr); \ } while (0) #define qr_after_insert(a_qrelm, a_qr, a_field) \ do \ { \ (a_qr)->a_field.qre_next = (a_qrelm)->a_field.qre_next; \ (a_qr)->a_field.qre_prev = (a_qrelm); \ (a_qr)->a_field.qre_next->a_field.qre_prev = (a_qr); \ (a_qrelm)->a_field.qre_next = (a_qr); \ } while (0) #define qr_meld(a_qr_a, a_qr_b, a_field) do { \ void *t; \ (a_qr_a)->a_field.qre_prev->a_field.qre_next = (a_qr_b); \ (a_qr_b)->a_field.qre_prev->a_field.qre_next = (a_qr_a); \ t = (a_qr_a)->a_field.qre_prev; \ (a_qr_a)->a_field.qre_prev = (a_qr_b)->a_field.qre_prev; \ (a_qr_b)->a_field.qre_prev = t; \ } while (0) /* qr_meld() and qr_split() are functionally equivalent, so there's no need to * have two copies of the code. */ #define qr_split(a_qr_a, a_qr_b, a_field) \ qr_meld((a_qr_a), (a_qr_b), a_field) #define qr_remove(a_qr, a_field) do { \ (a_qr)->a_field.qre_prev->a_field.qre_next \ = (a_qr)->a_field.qre_next; \ (a_qr)->a_field.qre_next->a_field.qre_prev \ = (a_qr)->a_field.qre_prev; \ (a_qr)->a_field.qre_next = (a_qr); \ (a_qr)->a_field.qre_prev = (a_qr); \ } while (0) #define qr_foreach(var, a_qr, a_field) \ for ((var) = (a_qr); \ (var) != NULL; \ (var) = (((var)->a_field.qre_next != (a_qr)) \ ? (var)->a_field.qre_next : NULL)) #define qr_reverse_foreach(var, a_qr, a_field) \ for ((var) = ((a_qr) != NULL) ? qr_prev(a_qr, a_field) : NULL; \ (var) != NULL; \ (var) = (((var) != (a_qr)) \ ? (var)->a_field.qre_prev : NULL))