@@ -8,7 +8,36 @@
#define _SYS_QUEUE_H_
/*
- * This file defines tail queues.
+ * This file defines four types of data structures: singly-linked lists,
+ * singly-linked tail queues, lists and tail queues.
+ *
+ * A singly-linked list is headed by a single forward pointer. The elements
+ * are singly linked for minimum space and pointer manipulation overhead at
+ * the expense of O(n) removal for arbitrary elements. New elements can be
+ * added to the list after an existing element or at the head of the list.
+ * Elements being removed from the head of the list should use the explicit
+ * macro for this purpose for optimum efficiency. A singly-linked list may
+ * only be traversed in the forward direction. Singly-linked lists are ideal
+ * for applications with large datasets and few or no removals or for
+ * implementing a LIFO queue.
+ *
+ * A singly-linked tail queue is headed by a pair of pointers, one to the
+ * head of the list and the other to the tail of the list. The elements are
+ * singly linked for minimum space and pointer manipulation overhead at the
+ * expense of O(n) removal for arbitrary elements. New elements can be added
+ * to the list after an existing element, at the head of the list, or at the
+ * end of the list. Elements being removed from the head of the tail queue
+ * should use the explicit macro for this purpose for optimum efficiency.
+ * A singly-linked tail queue may only be traversed in the forward direction.
+ * Singly-linked tail queues are ideal for applications with large datasets
+ * and few or no removals or for implementing a FIFO queue.
+ *
+ * A list is headed by a single forward pointer (or an array of forward
+ * pointers for a hash table header). The elements are doubly linked
+ * so that an arbitrary element can be removed without a need to
+ * traverse the list. New elements can be added to the list before
+ * or after an existing element or at the head of the list. A list
+ * may be traversed in either direction.
*
* A tail queue is headed by a pair of pointers, one to the head of the
* list and the other to the tail of the list. The elements are doubly
@@ -17,65 +46,93 @@
* after an existing element, at the head of the list, or at the end of
* the list. A tail queue may be traversed in either direction.
*
+ * For details on the use of these macros, see the queue(3) manual page.
+ *
* Below is a summary of implemented functions where:
* + means the macro is available
* - means the macro is not available
* s means the macro is available but is slow (runs in O(n) time)
*
- * TAILQ
- * _HEAD +
- * _CLASS_HEAD +
- * _HEAD_INITIALIZER +
- * _ENTRY +
- * _CLASS_ENTRY +
- * _INIT +
- * _EMPTY +
- * _FIRST +
- * _NEXT +
- * _PREV +
- * _LAST +
- * _LAST_FAST +
- * _FOREACH +
- * _FOREACH_FROM +
- * _FOREACH_SAFE +
- * _FOREACH_FROM_SAFE +
- * _FOREACH_REVERSE +
- * _FOREACH_REVERSE_FROM +
- * _FOREACH_REVERSE_SAFE +
- * _FOREACH_REVERSE_FROM_SAFE +
- * _INSERT_HEAD +
- * _INSERT_BEFORE +
- * _INSERT_AFTER +
- * _INSERT_TAIL +
- * _CONCAT +
- * _REMOVE_AFTER -
- * _REMOVE_HEAD -
- * _REMOVE +
- * _SWAP +
+ * SLIST LIST STAILQ TAILQ
+ * _HEAD + + + +
+ * _CLASS_HEAD + + + +
+ * _HEAD_INITIALIZER + + + +
+ * _ENTRY + + + +
+ * _CLASS_ENTRY + + + +
+ * _INIT + + + +
+ * _EMPTY + + + +
+ * _FIRST + + + +
+ * _NEXT + + + +
+ * _PREV - + - +
+ * _LAST - - + +
+ * _LAST_FAST - - - +
+ * _FOREACH + + + +
+ * _FOREACH_FROM + + + +
+ * _FOREACH_SAFE + + + +
+ * _FOREACH_FROM_SAFE + + + +
+ * _FOREACH_REVERSE - - - +
+ * _FOREACH_REVERSE_FROM - - - +
+ * _FOREACH_REVERSE_SAFE - - - +
+ * _FOREACH_REVERSE_FROM_SAFE - - - +
+ * _INSERT_HEAD + + + +
+ * _INSERT_BEFORE - + - +
+ * _INSERT_AFTER + + + +
+ * _INSERT_TAIL - - + +
+ * _CONCAT s s + +
+ * _REMOVE_AFTER + - + -
+ * _REMOVE_HEAD + - + -
+ * _REMOVE s + s +
+ * _SWAP + + + +
*
*/
-
-#ifdef __cplusplus
-extern "C" {
+#ifdef QUEUE_MACRO_DEBUG
+#warn Use QUEUE_MACRO_DEBUG_TRACE and/or QUEUE_MACRO_DEBUG_TRASH
+#define QUEUE_MACRO_DEBUG_TRACE
+#define QUEUE_MACRO_DEBUG_TRASH
#endif
-/*
- * List definitions.
- */
-#define LIST_HEAD(name, type) \
-struct name { \
- struct type *lh_first; /* first element */ \
-}
+#ifdef QUEUE_MACRO_DEBUG_TRACE
+/* Store the last 2 places the queue element or head was altered */
+struct qm_trace {
+ unsigned long lastline;
+ unsigned long prevline;
+ const char *lastfile;
+ const char *prevfile;
+};
+
+#define TRACEBUF struct qm_trace trace;
+#define TRACEBUF_INITIALIZER { __LINE__, 0, __FILE__, NULL } ,
+
+#define QMD_TRACE_HEAD(head) do { \
+ (head)->trace.prevline = (head)->trace.lastline; \
+ (head)->trace.prevfile = (head)->trace.lastfile; \
+ (head)->trace.lastline = __LINE__; \
+ (head)->trace.lastfile = __FILE__; \
+} while (0)
+#define QMD_TRACE_ELEM(elem) do { \
+ (elem)->trace.prevline = (elem)->trace.lastline; \
+ (elem)->trace.prevfile = (elem)->trace.lastfile; \
+ (elem)->trace.lastline = __LINE__; \
+ (elem)->trace.lastfile = __FILE__; \
+} while (0)
+
+#else /* !QUEUE_MACRO_DEBUG_TRACE */
#define QMD_TRACE_ELEM(elem)
#define QMD_TRACE_HEAD(head)
#define TRACEBUF
#define TRACEBUF_INITIALIZER
+#endif /* QUEUE_MACRO_DEBUG_TRACE */
+#ifdef QUEUE_MACRO_DEBUG_TRASH
+#define QMD_SAVELINK(name, link) void **name = (void *)&(link)
+#define TRASHIT(x) do {(x) = (void *)-1;} while (0)
+#define QMD_IS_TRASHED(x) ((x) == (void *)(intptr_t)-1)
+#else /* !QUEUE_MACRO_DEBUG_TRASH */
+#define QMD_SAVELINK(name, link)
#define TRASHIT(x)
#define QMD_IS_TRASHED(x) 0
-
-#define QMD_SAVELINK(name, link)
+#endif /* QUEUE_MACRO_DEBUG_TRASH */
#ifdef __cplusplus
/*
@@ -86,6 +143,445 @@ struct name { \
#define QUEUE_TYPEOF(type) struct type
#endif
+/*
+ * Singly-linked List declarations.
+ */
+#define SLIST_HEAD(name, type) \
+struct name { \
+ struct type *slh_first; /* first element */ \
+}
+
+#define SLIST_CLASS_HEAD(name, type) \
+struct name { \
+ class type *slh_first; /* first element */ \
+}
+
+#define SLIST_HEAD_INITIALIZER(head) \
+ { NULL }
+
+#define SLIST_ENTRY(type) \
+struct { \
+ struct type *sle_next; /* next element */ \
+}
+
+#define SLIST_CLASS_ENTRY(type) \
+struct { \
+ class type *sle_next; /* next element */ \
+}
+
+/*
+ * Singly-linked List functions.
+ */
+#if (defined(_KERNEL) && defined(INVARIANTS))
+#define QMD_SLIST_CHECK_PREVPTR(prevp, elm) do { \
+ if (*(prevp) != (elm)) \
+ panic("Bad prevptr *(%p) == %p != %p", \
+ (prevp), *(prevp), (elm)); \
+} while (0)
+#else
+#define QMD_SLIST_CHECK_PREVPTR(prevp, elm)
+#endif
+
+#define SLIST_CONCAT(head1, head2, type, field) do { \
+ QUEUE_TYPEOF(type) *curelm = SLIST_FIRST(head1); \
+ if (curelm == NULL) { \
+ if ((SLIST_FIRST(head1) = SLIST_FIRST(head2)) != NULL) \
+ SLIST_INIT(head2); \
+ } else if (SLIST_FIRST(head2) != NULL) { \
+ while (SLIST_NEXT(curelm, field) != NULL) \
+ curelm = SLIST_NEXT(curelm, field); \
+ SLIST_NEXT(curelm, field) = SLIST_FIRST(head2); \
+ SLIST_INIT(head2); \
+ } \
+} while (0)
+
+#define SLIST_EMPTY(head) ((head)->slh_first == NULL)
+
+#define SLIST_FIRST(head) ((head)->slh_first)
+
+#define SLIST_FOREACH(var, head, field) \
+ for ((var) = SLIST_FIRST((head)); \
+ (var); \
+ (var) = SLIST_NEXT((var), field))
+
+#define SLIST_FOREACH_FROM(var, head, field) \
+ for ((var) = ((var) ? (var) : SLIST_FIRST((head))); \
+ (var); \
+ (var) = SLIST_NEXT((var), field))
+
+#define SLIST_FOREACH_SAFE(var, head, field, tvar) \
+ for ((var) = SLIST_FIRST((head)); \
+ (var) && ((tvar) = SLIST_NEXT((var), field), 1); \
+ (var) = (tvar))
+
+#define SLIST_FOREACH_FROM_SAFE(var, head, field, tvar) \
+ for ((var) = ((var) ? (var) : SLIST_FIRST((head))); \
+ (var) && ((tvar) = SLIST_NEXT((var), field), 1); \
+ (var) = (tvar))
+
+#define SLIST_FOREACH_PREVPTR(var, varp, head, field) \
+ for ((varp) = &SLIST_FIRST((head)); \
+ ((var) = *(varp)) != NULL; \
+ (varp) = &SLIST_NEXT((var), field))
+
+#define SLIST_INIT(head) do { \
+ SLIST_FIRST((head)) = NULL; \
+} while (0)
+
+#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \
+ SLIST_NEXT((elm), field) = SLIST_NEXT((slistelm), field); \
+ SLIST_NEXT((slistelm), field) = (elm); \
+} while (0)
+
+#define SLIST_INSERT_HEAD(head, elm, field) do { \
+ SLIST_NEXT((elm), field) = SLIST_FIRST((head)); \
+ SLIST_FIRST((head)) = (elm); \
+} while (0)
+
+#define SLIST_NEXT(elm, field) ((elm)->field.sle_next)
+
+#define SLIST_REMOVE(head, elm, type, field) do { \
+ QMD_SAVELINK(oldnext, (elm)->field.sle_next); \
+ if (SLIST_FIRST((head)) == (elm)) { \
+ SLIST_REMOVE_HEAD((head), field); \
+ } \
+ else { \
+ QUEUE_TYPEOF(type) *curelm = SLIST_FIRST(head); \
+ while (SLIST_NEXT(curelm, field) != (elm)) \
+ curelm = SLIST_NEXT(curelm, field); \
+ SLIST_REMOVE_AFTER(curelm, field); \
+ } \
+ TRASHIT(*oldnext); \
+} while (0)
+
+#define SLIST_REMOVE_AFTER(elm, field) do { \
+ SLIST_NEXT(elm, field) = \
+ SLIST_NEXT(SLIST_NEXT(elm, field), field); \
+} while (0)
+
+#define SLIST_REMOVE_HEAD(head, field) do { \
+ SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field); \
+} while (0)
+
+#define SLIST_REMOVE_PREVPTR(prevp, elm, field) do { \
+ QMD_SLIST_CHECK_PREVPTR(prevp, elm); \
+ *(prevp) = SLIST_NEXT(elm, field); \
+ TRASHIT((elm)->field.sle_next); \
+} while (0)
+
+#define SLIST_SWAP(head1, head2, type) do { \
+ QUEUE_TYPEOF(type) *swap_first = SLIST_FIRST(head1); \
+ SLIST_FIRST(head1) = SLIST_FIRST(head2); \
+ SLIST_FIRST(head2) = swap_first; \
+} while (0)
+
+/*
+ * Singly-linked Tail queue declarations.
+ */
+#define STAILQ_HEAD(name, type) \
+struct name { \
+ struct type *stqh_first;/* first element */ \
+ struct type **stqh_last;/* addr of last next element */ \
+}
+
+#define STAILQ_CLASS_HEAD(name, type) \
+struct name { \
+ class type *stqh_first; /* first element */ \
+ class type **stqh_last; /* addr of last next element */ \
+}
+
+#define STAILQ_HEAD_INITIALIZER(head) \
+ { NULL, &(head).stqh_first }
+
+#define STAILQ_ENTRY(type) \
+struct { \
+ struct type *stqe_next; /* next element */ \
+}
+
+#define STAILQ_CLASS_ENTRY(type) \
+struct { \
+ class type *stqe_next; /* next element */ \
+}
+
+/*
+ * Singly-linked Tail queue functions.
+ */
+#define STAILQ_CONCAT(head1, head2) do { \
+ if (!STAILQ_EMPTY((head2))) { \
+ *(head1)->stqh_last = (head2)->stqh_first; \
+ (head1)->stqh_last = (head2)->stqh_last; \
+ STAILQ_INIT((head2)); \
+ } \
+} while (0)
+
+#define STAILQ_EMPTY(head) ((head)->stqh_first == NULL)
+
+#define STAILQ_FIRST(head) ((head)->stqh_first)
+
+#define STAILQ_FOREACH(var, head, field) \
+ for((var) = STAILQ_FIRST((head)); \
+ (var); \
+ (var) = STAILQ_NEXT((var), field))
+
+#define STAILQ_FOREACH_FROM(var, head, field) \
+ for ((var) = ((var) ? (var) : STAILQ_FIRST((head))); \
+ (var); \
+ (var) = STAILQ_NEXT((var), field))
+
+#define STAILQ_FOREACH_SAFE(var, head, field, tvar) \
+ for ((var) = STAILQ_FIRST((head)); \
+ (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \
+ (var) = (tvar))
+
+#define STAILQ_FOREACH_FROM_SAFE(var, head, field, tvar) \
+ for ((var) = ((var) ? (var) : STAILQ_FIRST((head))); \
+ (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \
+ (var) = (tvar))
+
+#define STAILQ_INIT(head) do { \
+ STAILQ_FIRST((head)) = NULL; \
+ (head)->stqh_last = &STAILQ_FIRST((head)); \
+} while (0)
+
+#define STAILQ_INSERT_AFTER(head, tqelm, elm, field) do { \
+ if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\
+ (head)->stqh_last = &STAILQ_NEXT((elm), field); \
+ STAILQ_NEXT((tqelm), field) = (elm); \
+} while (0)
+
+#define STAILQ_INSERT_HEAD(head, elm, field) do { \
+ if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL) \
+ (head)->stqh_last = &STAILQ_NEXT((elm), field); \
+ STAILQ_FIRST((head)) = (elm); \
+} while (0)
+
+#define STAILQ_INSERT_TAIL(head, elm, field) do { \
+ STAILQ_NEXT((elm), field) = NULL; \
+ *(head)->stqh_last = (elm); \
+ (head)->stqh_last = &STAILQ_NEXT((elm), field); \
+} while (0)
+
+#define STAILQ_LAST(head, type, field) \
+ (STAILQ_EMPTY((head)) ? NULL : \
+ __containerof((head)->stqh_last, \
+ QUEUE_TYPEOF(type), field.stqe_next))
+
+#define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next)
+
+#define STAILQ_REMOVE(head, elm, type, field) do { \
+ QMD_SAVELINK(oldnext, (elm)->field.stqe_next); \
+ if (STAILQ_FIRST((head)) == (elm)) { \
+ STAILQ_REMOVE_HEAD((head), field); \
+ } \
+ else { \
+ QUEUE_TYPEOF(type) *curelm = STAILQ_FIRST(head); \
+ while (STAILQ_NEXT(curelm, field) != (elm)) \
+ curelm = STAILQ_NEXT(curelm, field); \
+ STAILQ_REMOVE_AFTER(head, curelm, field); \
+ } \
+ TRASHIT(*oldnext); \
+} while (0)
+
+#define STAILQ_REMOVE_AFTER(head, elm, field) do { \
+ if ((STAILQ_NEXT(elm, field) = \
+ STAILQ_NEXT(STAILQ_NEXT(elm, field), field)) == NULL) \
+ (head)->stqh_last = &STAILQ_NEXT((elm), field); \
+} while (0)
+
+#define STAILQ_REMOVE_HEAD(head, field) do { \
+ if ((STAILQ_FIRST((head)) = \
+ STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL) \
+ (head)->stqh_last = &STAILQ_FIRST((head)); \
+} while (0)
+
+#define STAILQ_SWAP(head1, head2, type) do { \
+ QUEUE_TYPEOF(type) *swap_first = STAILQ_FIRST(head1); \
+ QUEUE_TYPEOF(type) **swap_last = (head1)->stqh_last; \
+ STAILQ_FIRST(head1) = STAILQ_FIRST(head2); \
+ (head1)->stqh_last = (head2)->stqh_last; \
+ STAILQ_FIRST(head2) = swap_first; \
+ (head2)->stqh_last = swap_last; \
+ if (STAILQ_EMPTY(head1)) \
+ (head1)->stqh_last = &STAILQ_FIRST(head1); \
+ if (STAILQ_EMPTY(head2)) \
+ (head2)->stqh_last = &STAILQ_FIRST(head2); \
+} while (0)
+
+
+/*
+ * List declarations.
+ */
+#define LIST_HEAD(name, type) \
+struct name { \
+ struct type *lh_first; /* first element */ \
+}
+
+#define LIST_CLASS_HEAD(name, type) \
+struct name { \
+ class type *lh_first; /* first element */ \
+}
+
+#define LIST_HEAD_INITIALIZER(head) \
+ { NULL }
+
+#define LIST_ENTRY(type) \
+struct { \
+ struct type *le_next; /* next element */ \
+ struct type **le_prev; /* address of previous next element */ \
+}
+
+#define LIST_CLASS_ENTRY(type) \
+struct { \
+ class type *le_next; /* next element */ \
+ class type **le_prev; /* address of previous next element */ \
+}
+
+/*
+ * List functions.
+ */
+
+#if (defined(_KERNEL) && defined(INVARIANTS))
+/*
+ * QMD_LIST_CHECK_HEAD(LIST_HEAD *head, LIST_ENTRY NAME)
+ *
+ * If the list is non-empty, validates that the first element of the list
+ * points back at 'head.'
+ */
+#define QMD_LIST_CHECK_HEAD(head, field) do { \
+ if (LIST_FIRST((head)) != NULL && \
+ LIST_FIRST((head))->field.le_prev != \
+ &LIST_FIRST((head))) \
+ panic("Bad list head %p first->prev != head", (head)); \
+} while (0)
+
+/*
+ * QMD_LIST_CHECK_NEXT(TYPE *elm, LIST_ENTRY NAME)
+ *
+ * If an element follows 'elm' in the list, validates that the next element
+ * points back at 'elm.'
+ */
+#define QMD_LIST_CHECK_NEXT(elm, field) do { \
+ if (LIST_NEXT((elm), field) != NULL && \
+ LIST_NEXT((elm), field)->field.le_prev != \
+ &((elm)->field.le_next)) \
+ panic("Bad link elm %p next->prev != elm", (elm)); \
+} while (0)
+
+/*
+ * QMD_LIST_CHECK_PREV(TYPE *elm, LIST_ENTRY NAME)
+ *
+ * Validates that the previous element (or head of the list) points to 'elm.'
+ */
+#define QMD_LIST_CHECK_PREV(elm, field) do { \
+ if (*(elm)->field.le_prev != (elm)) \
+ panic("Bad link elm %p prev->next != elm", (elm)); \
+} while (0)
+#else
+#define QMD_LIST_CHECK_HEAD(head, field)
+#define QMD_LIST_CHECK_NEXT(elm, field)
+#define QMD_LIST_CHECK_PREV(elm, field)
+#endif /* (_KERNEL && INVARIANTS) */
+
+#define LIST_CONCAT(head1, head2, type, field) do { \
+ QUEUE_TYPEOF(type) *curelm = LIST_FIRST(head1); \
+ if (curelm == NULL) { \
+ if ((LIST_FIRST(head1) = LIST_FIRST(head2)) != NULL) { \
+ LIST_FIRST(head2)->field.le_prev = \
+ &LIST_FIRST((head1)); \
+ LIST_INIT(head2); \
+ } \
+ } else if (LIST_FIRST(head2) != NULL) { \
+ while (LIST_NEXT(curelm, field) != NULL) \
+ curelm = LIST_NEXT(curelm, field); \
+ LIST_NEXT(curelm, field) = LIST_FIRST(head2); \
+ LIST_FIRST(head2)->field.le_prev = &LIST_NEXT(curelm, field); \
+ LIST_INIT(head2); \
+ } \
+} while (0)
+
+#define LIST_EMPTY(head) ((head)->lh_first == NULL)
+
+#define LIST_FIRST(head) ((head)->lh_first)
+
+#define LIST_FOREACH(var, head, field) \
+ for ((var) = LIST_FIRST((head)); \
+ (var); \
+ (var) = LIST_NEXT((var), field))
+
+#define LIST_FOREACH_FROM(var, head, field) \
+ for ((var) = ((var) ? (var) : LIST_FIRST((head))); \
+ (var); \
+ (var) = LIST_NEXT((var), field))
+
+#define LIST_FOREACH_SAFE(var, head, field, tvar) \
+ for ((var) = LIST_FIRST((head)); \
+ (var) && ((tvar) = LIST_NEXT((var), field), 1); \
+ (var) = (tvar))
+
+#define LIST_FOREACH_FROM_SAFE(var, head, field, tvar) \
+ for ((var) = ((var) ? (var) : LIST_FIRST((head))); \
+ (var) && ((tvar) = LIST_NEXT((var), field), 1); \
+ (var) = (tvar))
+
+#define LIST_INIT(head) do { \
+ LIST_FIRST((head)) = NULL; \
+} while (0)
+
+#define LIST_INSERT_AFTER(listelm, elm, field) do { \
+ QMD_LIST_CHECK_NEXT(listelm, field); \
+ if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\
+ LIST_NEXT((listelm), field)->field.le_prev = \
+ &LIST_NEXT((elm), field); \
+ LIST_NEXT((listelm), field) = (elm); \
+ (elm)->field.le_prev = &LIST_NEXT((listelm), field); \
+} while (0)
+
+#define LIST_INSERT_BEFORE(listelm, elm, field) do { \
+ QMD_LIST_CHECK_PREV(listelm, field); \
+ (elm)->field.le_prev = (listelm)->field.le_prev; \
+ LIST_NEXT((elm), field) = (listelm); \
+ *(listelm)->field.le_prev = (elm); \
+ (listelm)->field.le_prev = &LIST_NEXT((elm), field); \
+} while (0)
+
+#define LIST_INSERT_HEAD(head, elm, field) do { \
+ QMD_LIST_CHECK_HEAD((head), field); \
+ if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL) \
+ LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\
+ LIST_FIRST((head)) = (elm); \
+ (elm)->field.le_prev = &LIST_FIRST((head)); \
+} while (0)
+
+#define LIST_NEXT(elm, field) ((elm)->field.le_next)
+
+#define LIST_PREV(elm, head, type, field) \
+ ((elm)->field.le_prev == &LIST_FIRST((head)) ? NULL : \
+ __containerof((elm)->field.le_prev, \
+ QUEUE_TYPEOF(type), field.le_next))
+
+#define LIST_REMOVE(elm, field) do { \
+ QMD_SAVELINK(oldnext, (elm)->field.le_next); \
+ QMD_SAVELINK(oldprev, (elm)->field.le_prev); \
+ QMD_LIST_CHECK_NEXT(elm, field); \
+ QMD_LIST_CHECK_PREV(elm, field); \
+ if (LIST_NEXT((elm), field) != NULL) \
+ LIST_NEXT((elm), field)->field.le_prev = \
+ (elm)->field.le_prev; \
+ *(elm)->field.le_prev = LIST_NEXT((elm), field); \
+ TRASHIT(*oldnext); \
+ TRASHIT(*oldprev); \
+} while (0)
+
+#define LIST_SWAP(head1, head2, type, field) do { \
+ QUEUE_TYPEOF(type) *swap_tmp = LIST_FIRST(head1); \
+ LIST_FIRST((head1)) = LIST_FIRST((head2)); \
+ LIST_FIRST((head2)) = swap_tmp; \
+ if ((swap_tmp = LIST_FIRST((head1))) != NULL) \
+ swap_tmp->field.le_prev = &LIST_FIRST((head1)); \
+ if ((swap_tmp = LIST_FIRST((head2))) != NULL) \
+ swap_tmp->field.le_prev = &LIST_FIRST((head2)); \
+} while (0)
+
/*
* Tail queue declarations.
*/
@@ -123,10 +619,58 @@ struct { \
/*
* Tail queue functions.
*/
+#if (defined(_KERNEL) && defined(INVARIANTS))
+/*
+ * QMD_TAILQ_CHECK_HEAD(TAILQ_HEAD *head, TAILQ_ENTRY NAME)
+ *
+ * If the tailq is non-empty, validates that the first element of the tailq
+ * points back at 'head.'
+ */
+#define QMD_TAILQ_CHECK_HEAD(head, field) do { \
+ if (!TAILQ_EMPTY(head) && \
+ TAILQ_FIRST((head))->field.tqe_prev != \
+ &TAILQ_FIRST((head))) \
+ panic("Bad tailq head %p first->prev != head", (head)); \
+} while (0)
+
+/*
+ * QMD_TAILQ_CHECK_TAIL(TAILQ_HEAD *head, TAILQ_ENTRY NAME)
+ *
+ * Validates that the tail of the tailq is a pointer to pointer to NULL.
+ */
+#define QMD_TAILQ_CHECK_TAIL(head, field) do { \
+ if (*(head)->tqh_last != NULL) \
+ panic("Bad tailq NEXT(%p->tqh_last) != NULL", (head)); \
+} while (0)
+
+/*
+ * QMD_TAILQ_CHECK_NEXT(TYPE *elm, TAILQ_ENTRY NAME)
+ *
+ * If an element follows 'elm' in the tailq, validates that the next element
+ * points back at 'elm.'
+ */
+#define QMD_TAILQ_CHECK_NEXT(elm, field) do { \
+ if (TAILQ_NEXT((elm), field) != NULL && \
+ TAILQ_NEXT((elm), field)->field.tqe_prev != \
+ &((elm)->field.tqe_next)) \
+ panic("Bad link elm %p next->prev != elm", (elm)); \
+} while (0)
+
+/*
+ * QMD_TAILQ_CHECK_PREV(TYPE *elm, TAILQ_ENTRY NAME)
+ *
+ * Validates that the previous element (or head of the tailq) points to 'elm.'
+ */
+#define QMD_TAILQ_CHECK_PREV(elm, field) do { \
+ if (*(elm)->field.tqe_prev != (elm)) \
+ panic("Bad link elm %p prev->next != elm", (elm)); \
+} while (0)
+#else
#define QMD_TAILQ_CHECK_HEAD(head, field)
#define QMD_TAILQ_CHECK_TAIL(head, headname)
#define QMD_TAILQ_CHECK_NEXT(elm, field)
#define QMD_TAILQ_CHECK_PREV(elm, field)
+#endif /* (_KERNEL && INVARIANTS) */
#define TAILQ_CONCAT(head1, head2, field) do { \
if (!TAILQ_EMPTY(head2)) { \
@@ -191,9 +735,8 @@ struct { \
#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \
QMD_TAILQ_CHECK_NEXT(listelm, field); \
- TAILQ_NEXT((elm), field) = TAILQ_NEXT((listelm), field); \
- if (TAILQ_NEXT((listelm), field) != NULL) \
- TAILQ_NEXT((elm), field)->field.tqe_prev = \
+ if ((TAILQ_NEXT((elm), field) = TAILQ_NEXT((listelm), field)) != NULL)\
+ TAILQ_NEXT((elm), field)->field.tqe_prev = \
&TAILQ_NEXT((elm), field); \
else { \
(head)->tqh_last = &TAILQ_NEXT((elm), field); \
@@ -217,8 +760,7 @@ struct { \
#define TAILQ_INSERT_HEAD(head, elm, field) do { \
QMD_TAILQ_CHECK_HEAD(head, field); \
- TAILQ_NEXT((elm), field) = TAILQ_FIRST((head)); \
- if (TAILQ_FIRST((head)) != NULL) \
+ if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL) \
TAILQ_FIRST((head))->field.tqe_prev = \
&TAILQ_NEXT((elm), field); \
else \
@@ -250,21 +792,24 @@ struct { \
* you may want to prefetch the last data element.
*/
#define TAILQ_LAST_FAST(head, type, field) \
- (TAILQ_EMPTY(head) ? NULL : __containerof((head)->tqh_last, \
- QUEUE_TYPEOF(type), field.tqe_next))
+ (TAILQ_EMPTY(head) ? NULL : __containerof((head)->tqh_last, QUEUE_TYPEOF(type), field.tqe_next))
#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next)
#define TAILQ_PREV(elm, headname, field) \
(*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
+#define TAILQ_PREV_FAST(elm, head, type, field) \
+ ((elm)->field.tqe_prev == &(head)->tqh_first ? NULL : \
+ __containerof((elm)->field.tqe_prev, QUEUE_TYPEOF(type), field.tqe_next))
+
#define TAILQ_REMOVE(head, elm, field) do { \
QMD_SAVELINK(oldnext, (elm)->field.tqe_next); \
QMD_SAVELINK(oldprev, (elm)->field.tqe_prev); \
QMD_TAILQ_CHECK_NEXT(elm, field); \
QMD_TAILQ_CHECK_PREV(elm, field); \
if ((TAILQ_NEXT((elm), field)) != NULL) \
- TAILQ_NEXT((elm), field)->field.tqe_prev = \
+ TAILQ_NEXT((elm), field)->field.tqe_prev = \
(elm)->field.tqe_prev; \
else { \
(head)->tqh_last = (elm)->field.tqe_prev; \
@@ -277,26 +822,20 @@ struct { \
} while (0)
#define TAILQ_SWAP(head1, head2, type, field) do { \
- QUEUE_TYPEOF(type) * swap_first = (head1)->tqh_first; \
- QUEUE_TYPEOF(type) * *swap_last = (head1)->tqh_last; \
+ QUEUE_TYPEOF(type) *swap_first = (head1)->tqh_first; \
+ QUEUE_TYPEOF(type) **swap_last = (head1)->tqh_last; \
(head1)->tqh_first = (head2)->tqh_first; \
(head1)->tqh_last = (head2)->tqh_last; \
(head2)->tqh_first = swap_first; \
(head2)->tqh_last = swap_last; \
- swap_first = (head1)->tqh_first; \
- if (swap_first != NULL) \
+ if ((swap_first = (head1)->tqh_first) != NULL) \
swap_first->field.tqe_prev = &(head1)->tqh_first; \
else \
(head1)->tqh_last = &(head1)->tqh_first; \
- swap_first = (head2)->tqh_first; \
- if (swap_first != NULL) \
+ if ((swap_first = (head2)->tqh_first) != NULL) \
swap_first->field.tqe_prev = &(head2)->tqh_first; \
else \
(head2)->tqh_last = &(head2)->tqh_first; \
} while (0)
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* _SYS_QUEUE_H_ */
+#endif /* !_SYS_QUEUE_H_ */