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Sync queue(3) from FreeBSD

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Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=85147
This commit is contained in:
Guillem Jover 2014-11-01 00:22:28 +01:00
parent 3267114483
commit c7e01e9884
2 changed files with 274 additions and 30 deletions
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118
include/bsd/sys/queue.h
View File

@ -65,7 +65,7 @@
* 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 only be traversed in the forward direction.
* 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
@ -85,12 +85,16 @@
* _EMPTY + + + +
* _FIRST + + + +
* _NEXT + + + +
* _PREV - - - +
* _PREV - + - +
* _LAST - - + +
* _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 + + + +
@ -99,19 +103,22 @@
* _REMOVE_AFTER + - + -
* _REMOVE_HEAD + - + -
* _REMOVE + + + +
* _SWAP + + + +
*
*/
#ifdef QUEUE_MACRO_DEBUG
/* Store the last 2 places the queue element or head was altered */
struct qm_trace {
char * lastfile;
int lastline;
char * prevfile;
int prevline;
unsigned long lastline;
unsigned long prevline;
const char *lastfile;
const char *prevfile;
};
#define TRACEBUF struct qm_trace trace;
#define TRACEBUF_INITIALIZER { __FILE__, __LINE__, NULL, 0 } ,
#define TRASHIT(x) do {(x) = (void *)-1;} while (0)
#define QMD_SAVELINK(name, link) void **name = (void *)&(link)
#define QMD_TRACE_HEAD(head) do { \
(head)->trace.prevline = (head)->trace.lastline; \
@ -130,7 +137,9 @@ struct qm_trace {
#else
#define QMD_TRACE_ELEM(elem)
#define QMD_TRACE_HEAD(head)
#define QMD_SAVELINK(name, link)
#define TRACEBUF
#define TRACEBUF_INITIALIZER
#define TRASHIT(x)
#endif /* QUEUE_MACRO_DEBUG */
@ -162,11 +171,21 @@ struct { \
(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; \
@ -189,6 +208,7 @@ struct { \
#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); \
} \
@ -198,7 +218,7 @@ struct { \
curelm = SLIST_NEXT(curelm, field); \
SLIST_REMOVE_AFTER(curelm, field); \
} \
TRASHIT((elm)->field.sle_next); \
TRASHIT(*oldnext); \
} while (0)
#define SLIST_REMOVE_AFTER(elm, field) do { \
@ -210,6 +230,12 @@ struct { \
SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field); \
} while (0)
#define SLIST_SWAP(head1, head2, type) do { \
struct type *swap_first = SLIST_FIRST(head1); \
SLIST_FIRST(head1) = SLIST_FIRST(head2); \
SLIST_FIRST(head2) = swap_first; \
} while (0)
/*
* Singly-linked Tail queue declarations.
*/
@ -247,12 +273,21 @@ struct { \
(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)); \
@ -277,14 +312,13 @@ struct { \
} while (0)
#define STAILQ_LAST(head, type, field) \
(STAILQ_EMPTY((head)) ? \
NULL : \
((struct type *)(void *) \
((char *)((head)->stqh_last) - __offsetof(struct type, field))))
(STAILQ_EMPTY((head)) ? NULL : \
__containerof((head)->stqh_last, struct 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); \
} \
@ -294,13 +328,7 @@ struct { \
curelm = STAILQ_NEXT(curelm, field); \
STAILQ_REMOVE_AFTER(head, curelm, field); \
} \
TRASHIT((elm)->field.stqe_next); \
} 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)); \
TRASHIT(*oldnext); \
} while (0)
#define STAILQ_REMOVE_AFTER(head, elm, field) do { \
@ -309,6 +337,12 @@ struct { \
(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 { \
struct type *swap_first = STAILQ_FIRST(head1); \
struct type **swap_last = (head1)->stqh_last; \
@ -378,11 +412,21 @@ struct { \
(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)
@ -414,15 +458,21 @@ struct { \
#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, struct 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((elm)->field.le_next); \
TRASHIT((elm)->field.le_prev); \
TRASHIT(*oldnext); \
TRASHIT(*oldprev); \
} while (0)
#define LIST_SWAP(head1, head2, type, field) do { \
@ -446,7 +496,7 @@ struct name { \
}
#define TAILQ_HEAD_INITIALIZER(head) \
{ NULL, &(head).tqh_first }
{ NULL, &(head).tqh_first, TRACEBUF_INITIALIZER }
#define TAILQ_ENTRY(type) \
struct { \
@ -509,21 +559,41 @@ struct { \
(var); \
(var) = TAILQ_NEXT((var), field))
#define TAILQ_FOREACH_FROM(var, head, field) \
for ((var) = ((var) ? (var) : TAILQ_FIRST((head))); \
(var); \
(var) = TAILQ_NEXT((var), field))
#define TAILQ_FOREACH_SAFE(var, head, field, tvar) \
for ((var) = TAILQ_FIRST((head)); \
(var) && ((tvar) = TAILQ_NEXT((var), field), 1); \
(var) = (tvar))
#define TAILQ_FOREACH_FROM_SAFE(var, head, field, tvar) \
for ((var) = ((var) ? (var) : TAILQ_FIRST((head))); \
(var) && ((tvar) = TAILQ_NEXT((var), field), 1); \
(var) = (tvar))
#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \
for ((var) = TAILQ_LAST((head), headname); \
(var); \
(var) = TAILQ_PREV((var), headname, field))
#define TAILQ_FOREACH_REVERSE_FROM(var, head, headname, field) \
for ((var) = ((var) ? (var) : TAILQ_LAST((head), headname)); \
(var); \
(var) = TAILQ_PREV((var), headname, field))
#define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \
for ((var) = TAILQ_LAST((head), headname); \
(var) && ((tvar) = TAILQ_PREV((var), headname, field), 1); \
(var) = (tvar))
#define TAILQ_FOREACH_REVERSE_FROM_SAFE(var, head, headname, field, tvar) \
for ((var) = ((var) ? (var) : TAILQ_LAST((head), headname)); \
(var) && ((tvar) = TAILQ_PREV((var), headname, field), 1); \
(var) = (tvar))
#define TAILQ_INIT(head) do { \
TAILQ_FIRST((head)) = NULL; \
(head)->tqh_last = &TAILQ_FIRST((head)); \
@ -587,6 +657,8 @@ struct { \
(*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
#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) \
@ -597,8 +669,8 @@ struct { \
QMD_TRACE_HEAD(head); \
} \
*(elm)->field.tqe_prev = TAILQ_NEXT((elm), field); \
TRASHIT((elm)->field.tqe_next); \
TRASHIT((elm)->field.tqe_prev); \
TRASHIT(*oldnext); \
TRASHIT(*oldprev); \
QMD_TRACE_ELEM(&(elm)->field); \
} while (0)

186
man/queue.3bsd
View File

@ -9,7 +9,7 @@
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 4. Neither the name of the University nor the names of its contributors
.\" 3. Neither the name of the University nor the names of its contributors
.\" may be used to endorse or promote products derived from this software
.\" without specific prior written permission.
.\"
@ -28,15 +28,17 @@
.\" @(#)queue.3 8.2 (Berkeley) 1/24/94
.\" $FreeBSD$
.\"
.Dd May 13, 2011
.Dt QUEUE 3bsd
.Dd June 17, 2013
.Dt QUEUE 3
.Os
.Sh NAME
.Nm SLIST_EMPTY ,
.Nm SLIST_ENTRY ,
.Nm SLIST_FIRST ,
.Nm SLIST_FOREACH ,
.Nm SLIST_FOREACH_FROM ,
.Nm SLIST_FOREACH_SAFE ,
.Nm SLIST_FOREACH_FROM_SAFE ,
.Nm SLIST_HEAD ,
.Nm SLIST_HEAD_INITIALIZER ,
.Nm SLIST_INIT ,
@ -52,7 +54,9 @@
.Nm STAILQ_ENTRY ,
.Nm STAILQ_FIRST ,
.Nm STAILQ_FOREACH ,
.Nm STAILQ_FOREACH_FROM ,
.Nm STAILQ_FOREACH_SAFE ,
.Nm STAILQ_FOREACH_FROM_SAFE ,
.Nm STAILQ_HEAD ,
.Nm STAILQ_HEAD_INITIALIZER ,
.Nm STAILQ_INIT ,
@ -69,7 +73,9 @@
.Nm LIST_ENTRY ,
.Nm LIST_FIRST ,
.Nm LIST_FOREACH ,
.Nm LIST_FOREACH_FROM ,
.Nm LIST_FOREACH_SAFE ,
.Nm LIST_FOREACH_FROM_SAFE ,
.Nm LIST_HEAD ,
.Nm LIST_HEAD_INITIALIZER ,
.Nm LIST_INIT ,
@ -77,6 +83,7 @@
.Nm LIST_INSERT_BEFORE ,
.Nm LIST_INSERT_HEAD ,
.Nm LIST_NEXT ,
.Nm LIST_PREV ,
.Nm LIST_REMOVE ,
.Nm LIST_SWAP ,
.Nm TAILQ_CONCAT ,
@ -84,9 +91,13 @@
.Nm TAILQ_ENTRY ,
.Nm TAILQ_FIRST ,
.Nm TAILQ_FOREACH ,
.Nm TAILQ_FOREACH_FROM ,
.Nm TAILQ_FOREACH_SAFE ,
.Nm TAILQ_FOREACH_FROM_SAFE ,
.Nm TAILQ_FOREACH_REVERSE ,
.Nm TAILQ_FOREACH_REVERSE_FROM ,
.Nm TAILQ_FOREACH_REVERSE_SAFE ,
.Nm TAILQ_FOREACH_REVERSE_FROM_SAFE ,
.Nm TAILQ_HEAD ,
.Nm TAILQ_HEAD_INITIALIZER ,
.Nm TAILQ_INIT ,
@ -108,7 +119,9 @@ lists and tail queues
.Fn SLIST_ENTRY "TYPE"
.Fn SLIST_FIRST "SLIST_HEAD *head"
.Fn SLIST_FOREACH "TYPE *var" "SLIST_HEAD *head" "SLIST_ENTRY NAME"
.Fn SLIST_FOREACH_FROM "TYPE *var" "SLIST_HEAD *head" "SLIST_ENTRY NAME"
.Fn SLIST_FOREACH_SAFE "TYPE *var" "SLIST_HEAD *head" "SLIST_ENTRY NAME" "TYPE *temp_var"
.Fn SLIST_FOREACH_FROM_SAFE "TYPE *var" "SLIST_HEAD *head" "SLIST_ENTRY NAME" "TYPE *temp_var"
.Fn SLIST_HEAD "HEADNAME" "TYPE"
.Fn SLIST_HEAD_INITIALIZER "SLIST_HEAD head"
.Fn SLIST_INIT "SLIST_HEAD *head"
@ -125,7 +138,9 @@ lists and tail queues
.Fn STAILQ_ENTRY "TYPE"
.Fn STAILQ_FIRST "STAILQ_HEAD *head"
.Fn STAILQ_FOREACH "TYPE *var" "STAILQ_HEAD *head" "STAILQ_ENTRY NAME"
.Fn STAILQ_FOREACH_FROM "TYPE *var" "STAILQ_HEAD *head" "STAILQ_ENTRY NAME"
.Fn STAILQ_FOREACH_SAFE "TYPE *var" "STAILQ_HEAD *head" "STAILQ_ENTRY NAME" "TYPE *temp_var"
.Fn STAILQ_FOREACH_FROM_SAFE "TYPE *var" "STAILQ_HEAD *head" "STAILQ_ENTRY NAME" "TYPE *temp_var"
.Fn STAILQ_HEAD "HEADNAME" "TYPE"
.Fn STAILQ_HEAD_INITIALIZER "STAILQ_HEAD head"
.Fn STAILQ_INIT "STAILQ_HEAD *head"
@ -143,7 +158,9 @@ lists and tail queues
.Fn LIST_ENTRY "TYPE"
.Fn LIST_FIRST "LIST_HEAD *head"
.Fn LIST_FOREACH "TYPE *var" "LIST_HEAD *head" "LIST_ENTRY NAME"
.Fn LIST_FOREACH_FROM "TYPE *var" "LIST_HEAD *head" "LIST_ENTRY NAME"
.Fn LIST_FOREACH_SAFE "TYPE *var" "LIST_HEAD *head" "LIST_ENTRY NAME" "TYPE *temp_var"
.Fn LIST_FOREACH_FROM_SAFE "TYPE *var" "LIST_HEAD *head" "LIST_ENTRY NAME" "TYPE *temp_var"
.Fn LIST_HEAD "HEADNAME" "TYPE"
.Fn LIST_HEAD_INITIALIZER "LIST_HEAD head"
.Fn LIST_INIT "LIST_HEAD *head"
@ -151,6 +168,7 @@ lists and tail queues
.Fn LIST_INSERT_BEFORE "TYPE *listelm" "TYPE *elm" "LIST_ENTRY NAME"
.Fn LIST_INSERT_HEAD "LIST_HEAD *head" "TYPE *elm" "LIST_ENTRY NAME"
.Fn LIST_NEXT "TYPE *elm" "LIST_ENTRY NAME"
.Fn LIST_PREV "TYPE *elm" "LIST_HEAD *head" "TYPE" "LIST_ENTRY NAME"
.Fn LIST_REMOVE "TYPE *elm" "LIST_ENTRY NAME"
.Fn LIST_SWAP "LIST_HEAD *head1" "LIST_HEAD *head2" "TYPE" "LIST_ENTRY NAME"
.\"
@ -159,9 +177,13 @@ lists and tail queues
.Fn TAILQ_ENTRY "TYPE"
.Fn TAILQ_FIRST "TAILQ_HEAD *head"
.Fn TAILQ_FOREACH "TYPE *var" "TAILQ_HEAD *head" "TAILQ_ENTRY NAME"
.Fn TAILQ_FOREACH_FROM "TYPE *var" "TAILQ_HEAD *head" "TAILQ_ENTRY NAME"
.Fn TAILQ_FOREACH_SAFE "TYPE *var" "TAILQ_HEAD *head" "TAILQ_ENTRY NAME" "TYPE *temp_var"
.Fn TAILQ_FOREACH_FROM_SAFE "TYPE *var" "TAILQ_HEAD *head" "TAILQ_ENTRY NAME" "TYPE *temp_var"
.Fn TAILQ_FOREACH_REVERSE "TYPE *var" "TAILQ_HEAD *head" "HEADNAME" "TAILQ_ENTRY NAME"
.Fn TAILQ_FOREACH_REVERSE_FROM "TYPE *var" "TAILQ_HEAD *head" "HEADNAME" "TAILQ_ENTRY NAME"
.Fn TAILQ_FOREACH_REVERSE_SAFE "TYPE *var" "TAILQ_HEAD *head" "HEADNAME" "TAILQ_ENTRY NAME" "TYPE *temp_var"
.Fn TAILQ_FOREACH_REVERSE_FROM_SAFE "TYPE *var" "TAILQ_HEAD *head" "HEADNAME" "TAILQ_ENTRY NAME" "TYPE *temp_var"
.Fn TAILQ_HEAD "HEADNAME" "TYPE"
.Fn TAILQ_HEAD_INITIALIZER "TAILQ_HEAD head"
.Fn TAILQ_INIT "TAILQ_HEAD *head"
@ -244,8 +266,18 @@ Code size and execution time of operations (except for removal) is about
twice that of the singly-linked data-structures.
.El
.Pp
Linked lists are the simplest of the doubly linked data structures and support
only the above functionality over singly-linked lists.
Linked lists are the simplest of the doubly linked data structures.
They add the following functionality over the above:
.Bl -enum -compact -offset indent
.It
They may be traversed backwards.
.El
However:
.Bl -enum -compact -offset indent
.It
To traverse backwards, an entry to begin the traversal and the list in
which it is contained must be specified.
.El
.Pp
Tail queues add the following functionality:
.Bl -enum -compact -offset indent
@ -349,6 +381,19 @@ turn to
.Fa var .
.Pp
The macro
.Nm SLIST_FOREACH_FROM
behaves identically to
.Nm SLIST_FOREACH
when
.Fa var
is NULL, else it treats
.Fa var
as a previously found SLIST element and begins the loop at
.Fa var
instead of the first element in the SLIST referenced by
.Fa head .
.Pp
The macro
.Nm SLIST_FOREACH_SAFE
traverses the list referenced by
.Fa head
@ -363,6 +408,19 @@ as well as free it from within the loop safely without interfering with the
traversal.
.Pp
The macro
.Nm SLIST_FOREACH_FROM_SAFE
behaves identically to
.Nm SLIST_FOREACH_SAFE
when
.Fa var
is NULL, else it treats
.Fa var
as a previously found SLIST element and begins the loop at
.Fa var
instead of the first element in the SLIST referenced by
.Fa head .
.Pp
The macro
.Nm SLIST_INIT
initializes the list referenced by
.Fa head .
@ -388,7 +446,8 @@ The macro
.Nm SLIST_REMOVE_AFTER
removes the element after
.Fa elm
from the list. Unlike
from the list.
Unlike
.Fa SLIST_REMOVE ,
this macro does not traverse the entire list.
.Pp
@ -528,6 +587,19 @@ in turn to
.Fa var .
.Pp
The macro
.Nm STAILQ_FOREACH_FROM
behaves identically to
.Nm STAILQ_FOREACH
when
.Fa var
is NULL, else it treats
.Fa var
as a previously found STAILQ element and begins the loop at
.Fa var
instead of the first element in the STAILQ referenced by
.Fa head .
.Pp
The macro
.Nm STAILQ_FOREACH_SAFE
traverses the tail queue referenced by
.Fa head
@ -542,6 +614,19 @@ as well as free it from within the loop safely without interfering with the
traversal.
.Pp
The macro
.Nm STAILQ_FOREACH_FROM_SAFE
behaves identically to
.Nm STAILQ_FOREACH_SAFE
when
.Fa var
is NULL, else it treats
.Fa var
as a previously found STAILQ element and begins the loop at
.Fa var
instead of the first element in the STAILQ referenced by
.Fa head .
.Pp
The macro
.Nm STAILQ_INIT
initializes the tail queue referenced by
.Fa head .
@ -579,7 +664,8 @@ The macro
.Nm STAILQ_REMOVE_AFTER
removes the element after
.Fa elm
from the tail queue. Unlike
from the tail queue.
Unlike
.Fa STAILQ_REMOVE ,
this macro does not traverse the entire tail queue.
.Pp
@ -717,6 +803,19 @@ in the forward direction, assigning each element in turn to
.Fa var .
.Pp
The macro
.Nm LIST_FOREACH_FROM
behaves identically to
.Nm LIST_FOREACH
when
.Fa var
is NULL, else it treats
.Fa var
as a previously found LIST element and begins the loop at
.Fa var
instead of the first element in the LIST referenced by
.Fa head .
.Pp
The macro
.Nm LIST_FOREACH_SAFE
traverses the list referenced by
.Fa head
@ -730,6 +829,19 @@ as well as free it from within the loop safely without interfering with the
traversal.
.Pp
The macro
.Nm LIST_FOREACH_FROM_SAFE
behaves identically to
.Nm LIST_FOREACH_SAFE
when
.Fa var
is NULL, else it treats
.Fa var
as a previously found LIST element and begins the loop at
.Fa var
instead of the first element in the LIST referenced by
.Fa head .
.Pp
The macro
.Nm LIST_INIT
initializes the list referenced by
.Fa head .
@ -759,6 +871,14 @@ The macro
returns the next element in the list, or NULL if this is the last.
.Pp
The macro
.Nm LIST_PREV
returns the previous element in the list, or NULL if this is the first.
List
.Fa head
must contain element
.Fa elm .
.Pp
The macro
.Nm LIST_REMOVE
removes the element
.Fa elm
@ -894,12 +1014,38 @@ is set to
if the loop completes normally, or if there were no elements.
.Pp
The macro
.Nm TAILQ_FOREACH_FROM
behaves identically to
.Nm TAILQ_FOREACH
when
.Fa var
is NULL, else it treats
.Fa var
as a previously found TAILQ element and begins the loop at
.Fa var
instead of the first element in the TAILQ referenced by
.Fa head .
.Pp
The macro
.Nm TAILQ_FOREACH_REVERSE
traverses the tail queue referenced by
.Fa head
in the reverse direction, assigning each element in turn to
.Fa var .
.Pp
The macro
.Nm TAILQ_FOREACH_REVERSE_FROM
behaves identically to
.Nm TAILQ_FOREACH_REVERSE
when
.Fa var
is NULL, else it treats
.Fa var
as a previously found TAILQ element and begins the reverse loop at
.Fa var
instead of the last element in the TAILQ referenced by
.Fa head .
.Pp
The macros
.Nm TAILQ_FOREACH_SAFE
and
@ -919,6 +1065,32 @@ as well as free it from within the loop safely without interfering with the
traversal.
.Pp
The macro
.Nm TAILQ_FOREACH_FROM_SAFE
behaves identically to
.Nm TAILQ_FOREACH_SAFE
when
.Fa var
is NULL, else it treats
.Fa var
as a previously found TAILQ element and begins the loop at
.Fa var
instead of the first element in the TAILQ referenced by
.Fa head .
.Pp
The macro
.Nm TAILQ_FOREACH_REVERSE_FROM_SAFE
behaves identically to
.Nm TAILQ_FOREACH_REVERSE_SAFE
when
.Fa var
is NULL, else it treats
.Fa var
as a previously found TAILQ element and begins the reverse loop at
.Fa var
instead of the last element in the TAILQ referenced by
.Fa head .
.Pp
The macro
.Nm TAILQ_INIT
initializes the tail queue referenced by
.Fa head .