diff options
Diffstat (limited to 'include/qemu/queue.h')
-rw-r--r-- | include/qemu/queue.h | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/include/qemu/queue.h b/include/qemu/queue.h index 342073f..35292c3 100644 --- a/include/qemu/queue.h +++ b/include/qemu/queue.h @@ -438,4 +438,64 @@ struct { \ #define QTAILQ_PREV(elm, headname, field) \ (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) +#define field_at_offset(base, offset, type) \ + ((type) (((char *) (base)) + (offset))) + +typedef struct DUMMY_Q_ENTRY DUMMY_Q_ENTRY; +typedef struct DUMMY_Q DUMMY_Q; + +struct DUMMY_Q_ENTRY { + QTAILQ_ENTRY(DUMMY_Q_ENTRY) next; +}; + +struct DUMMY_Q { + QTAILQ_HEAD(DUMMY_Q_HEAD, DUMMY_Q_ENTRY) head; +}; + +#define dummy_q ((DUMMY_Q *) 0) +#define dummy_qe ((DUMMY_Q_ENTRY *) 0) + +/* + * Offsets of layout of a tail queue head. + */ +#define QTAILQ_FIRST_OFFSET (offsetof(typeof(dummy_q->head), tqh_first)) +#define QTAILQ_LAST_OFFSET (offsetof(typeof(dummy_q->head), tqh_last)) +/* + * Raw access of elements of a tail queue + */ +#define QTAILQ_RAW_FIRST(head) \ + (*field_at_offset(head, QTAILQ_FIRST_OFFSET, void **)) +#define QTAILQ_RAW_TQH_LAST(head) \ + (*field_at_offset(head, QTAILQ_LAST_OFFSET, void ***)) + +/* + * Offsets of layout of a tail queue element. + */ +#define QTAILQ_NEXT_OFFSET (offsetof(typeof(dummy_qe->next), tqe_next)) +#define QTAILQ_PREV_OFFSET (offsetof(typeof(dummy_qe->next), tqe_prev)) + +/* + * Raw access of elements of a tail entry + */ +#define QTAILQ_RAW_NEXT(elm, entry) \ + (*field_at_offset(elm, entry + QTAILQ_NEXT_OFFSET, void **)) +#define QTAILQ_RAW_TQE_PREV(elm, entry) \ + (*field_at_offset(elm, entry + QTAILQ_PREV_OFFSET, void ***)) +/* + * Tail queue tranversal using pointer arithmetic. + */ +#define QTAILQ_RAW_FOREACH(elm, head, entry) \ + for ((elm) = QTAILQ_RAW_FIRST(head); \ + (elm); \ + (elm) = QTAILQ_RAW_NEXT(elm, entry)) +/* + * Tail queue insertion using pointer arithmetic. + */ +#define QTAILQ_RAW_INSERT_TAIL(head, elm, entry) do { \ + QTAILQ_RAW_NEXT(elm, entry) = NULL; \ + QTAILQ_RAW_TQE_PREV(elm, entry) = QTAILQ_RAW_TQH_LAST(head); \ + *QTAILQ_RAW_TQH_LAST(head) = (elm); \ + QTAILQ_RAW_TQH_LAST(head) = &QTAILQ_RAW_NEXT(elm, entry); \ +} while (/*CONSTCOND*/0) + #endif /* QEMU_SYS_QUEUE_H */ |