#define QSIMPLEQ_FIRST(head) ((head)->sqh_first)
#define QSIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next)
+typedef struct QTailQLink {
+ void *tql_next;
+ struct QTailQLink *tql_prev;
+} QTailQLink;
/*
- * Tail queue definitions.
+ * Tail queue definitions. The union acts as a poor man template, as if
+ * it were QTailQLink<type>.
*/
-#define Q_TAILQ_HEAD(name, type, qual) \
-struct name { \
- qual type *tqh_first; /* first element */ \
- qual type *qual *tqh_last; /* addr of last next element */ \
+#define QTAILQ_HEAD(name, type) \
+union name { \
+ struct type *tqh_first; /* first element */ \
+ QTailQLink tqh_circ; /* link for circular backwards list */ \
}
-#define QTAILQ_HEAD(name, type) Q_TAILQ_HEAD(name, struct type,)
#define QTAILQ_HEAD_INITIALIZER(head) \
- { NULL, &(head).tqh_first }
+ { .tqh_circ = { NULL, &(head).tqh_circ } }
-#define Q_TAILQ_ENTRY(type, qual) \
-struct { \
- qual type *tqe_next; /* next element */ \
- qual type *qual *tqe_prev; /* address of previous next element */\
+#define QTAILQ_ENTRY(type) \
+union { \
+ struct type *tqe_next; /* next element */ \
+ QTailQLink tqe_circ; /* link for circular backwards list */ \
}
-#define QTAILQ_ENTRY(type) Q_TAILQ_ENTRY(struct type,)
/*
* Tail queue functions.
*/
#define QTAILQ_INIT(head) do { \
(head)->tqh_first = NULL; \
- (head)->tqh_last = &(head)->tqh_first; \
+ (head)->tqh_circ.tql_prev = &(head)->tqh_circ; \
} while (/*CONSTCOND*/0)
#define QTAILQ_INSERT_HEAD(head, elm, field) do { \
if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \
- (head)->tqh_first->field.tqe_prev = \
- &(elm)->field.tqe_next; \
+ (head)->tqh_first->field.tqe_circ.tql_prev = \
+ &(elm)->field.tqe_circ; \
else \
- (head)->tqh_last = &(elm)->field.tqe_next; \
+ (head)->tqh_circ.tql_prev = &(elm)->field.tqe_circ; \
(head)->tqh_first = (elm); \
- (elm)->field.tqe_prev = &(head)->tqh_first; \
+ (elm)->field.tqe_circ.tql_prev = &(head)->tqh_circ; \
} while (/*CONSTCOND*/0)
#define QTAILQ_INSERT_TAIL(head, elm, field) do { \
(elm)->field.tqe_next = NULL; \
- (elm)->field.tqe_prev = (head)->tqh_last; \
- *(head)->tqh_last = (elm); \
- (head)->tqh_last = &(elm)->field.tqe_next; \
+ (elm)->field.tqe_circ.tql_prev = (head)->tqh_circ.tql_prev; \
+ (head)->tqh_circ.tql_prev->tql_next = (elm); \
+ (head)->tqh_circ.tql_prev = &(elm)->field.tqe_circ; \
} while (/*CONSTCOND*/0)
#define QTAILQ_INSERT_AFTER(head, listelm, elm, field) do { \
if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\
- (elm)->field.tqe_next->field.tqe_prev = \
- &(elm)->field.tqe_next; \
+ (elm)->field.tqe_next->field.tqe_circ.tql_prev = \
+ &(elm)->field.tqe_circ; \
else \
- (head)->tqh_last = &(elm)->field.tqe_next; \
+ (head)->tqh_circ.tql_prev = &(elm)->field.tqe_circ; \
(listelm)->field.tqe_next = (elm); \
- (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \
+ (elm)->field.tqe_circ.tql_prev = &(listelm)->field.tqe_circ; \
} while (/*CONSTCOND*/0)
-#define QTAILQ_INSERT_BEFORE(listelm, elm, field) do { \
- (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \
- (elm)->field.tqe_next = (listelm); \
- *(listelm)->field.tqe_prev = (elm); \
- (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \
+#define QTAILQ_INSERT_BEFORE(listelm, elm, field) do { \
+ (elm)->field.tqe_circ.tql_prev = (listelm)->field.tqe_circ.tql_prev; \
+ (elm)->field.tqe_next = (listelm); \
+ (listelm)->field.tqe_circ.tql_prev->tql_next = (elm); \
+ (listelm)->field.tqe_circ.tql_prev = &(elm)->field.tqe_circ; \
} while (/*CONSTCOND*/0)
#define QTAILQ_REMOVE(head, elm, field) do { \
if (((elm)->field.tqe_next) != NULL) \
- (elm)->field.tqe_next->field.tqe_prev = \
- (elm)->field.tqe_prev; \
+ (elm)->field.tqe_next->field.tqe_circ.tql_prev = \
+ (elm)->field.tqe_circ.tql_prev; \
else \
- (head)->tqh_last = (elm)->field.tqe_prev; \
- *(elm)->field.tqe_prev = (elm)->field.tqe_next; \
- (elm)->field.tqe_prev = NULL; \
+ (head)->tqh_circ.tql_prev = (elm)->field.tqe_circ.tql_prev; \
+ (elm)->field.tqe_circ.tql_prev->tql_next = (elm)->field.tqe_next; \
+ (elm)->field.tqe_circ.tql_prev = NULL; \
} while (/*CONSTCOND*/0)
#define QTAILQ_FOREACH(var, head, field) \
(var) && ((next_var) = ((var)->field.tqe_next), 1); \
(var) = (next_var))
-#define QTAILQ_FOREACH_REVERSE(var, head, headname, field) \
- for ((var) = (*(((struct headname *)((head)->tqh_last))->tqh_last)); \
+#define QTAILQ_FOREACH_REVERSE(var, head, field) \
+ for ((var) = QTAILQ_LAST(head); \
(var); \
- (var) = (*(((struct headname *)((var)->field.tqe_prev))->tqh_last)))
+ (var) = QTAILQ_PREV(var, field))
-#define QTAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, prev_var) \
- for ((var) = (*(((struct headname *)((head)->tqh_last))->tqh_last)); \
- (var) && ((prev_var) = (*(((struct headname *)((var)->field.tqe_prev))->tqh_last)), 1); \
+#define QTAILQ_FOREACH_REVERSE_SAFE(var, head, field, prev_var) \
+ for ((var) = QTAILQ_LAST(head); \
+ (var) && ((prev_var) = QTAILQ_PREV(var, field), 1); \
(var) = (prev_var))
/*
#define QTAILQ_EMPTY(head) ((head)->tqh_first == NULL)
#define QTAILQ_FIRST(head) ((head)->tqh_first)
#define QTAILQ_NEXT(elm, field) ((elm)->field.tqe_next)
-#define QTAILQ_IN_USE(elm, field) ((elm)->field.tqe_prev != NULL)
+#define QTAILQ_IN_USE(elm, field) ((elm)->field.tqe_circ.tql_prev != NULL)
-#define QTAILQ_LAST(head, headname) \
- (*(((struct headname *)((head)->tqh_last))->tqh_last))
-#define QTAILQ_PREV(elm, headname, field) \
- (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
+#define QTAILQ_LINK_PREV(link) \
+ ((link).tql_prev->tql_prev->tql_next)
+#define QTAILQ_LAST(head) \
+ ((typeof((head)->tqh_first)) QTAILQ_LINK_PREV((head)->tqh_circ))
+#define QTAILQ_PREV(elm, field) \
+ ((typeof((elm)->field.tqe_next)) QTAILQ_LINK_PREV((elm)->field.tqe_circ))
#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)
+ ((type *) (((char *) (base)) + (offset)))
/*
- * 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
+ * Raw access of elements of a tail queue head. Offsets are all zero
+ * because it's a union.
*/
#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))
+ field_at_offset(head, 0, void *)
+#define QTAILQ_RAW_TQH_CIRC(head) \
+ field_at_offset(head, 0, QTailQLink)
/*
* 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 ***))
+ field_at_offset(elm, entry, void *)
+#define QTAILQ_RAW_TQE_CIRC(elm, entry) \
+ field_at_offset(elm, entry, QTailQLink)
/*
- * Tail queue tranversal using pointer arithmetic.
+ * Tail queue traversal using pointer arithmetic.
*/
#define QTAILQ_RAW_FOREACH(elm, head, entry) \
- for ((elm) = QTAILQ_RAW_FIRST(head); \
+ for ((elm) = *QTAILQ_RAW_FIRST(head); \
(elm); \
- (elm) = QTAILQ_RAW_NEXT(elm, entry))
+ (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); \
+#define QTAILQ_RAW_INSERT_TAIL(head, elm, entry) do { \
+ *QTAILQ_RAW_NEXT(elm, entry) = NULL; \
+ QTAILQ_RAW_TQE_CIRC(elm, entry)->tql_prev = QTAILQ_RAW_TQH_CIRC(head)->tql_prev; \
+ QTAILQ_RAW_TQH_CIRC(head)->tql_prev->tql_next = (elm); \
+ QTAILQ_RAW_TQH_CIRC(head)->tql_prev = QTAILQ_RAW_TQE_CIRC(elm, entry); \
} while (/*CONSTCOND*/0)
#endif /* QEMU_SYS_QUEUE_H */
projects / qemu.git / blobdiff