@@ -31,66 +31,90 @@
.\"
.TH STAILQ 3 2020-10-21 "GNU" "Linux Programmer's Manual"
.SH NAME
-.Nm STAILQ_CONCAT ,
-.Nm STAILQ_EMPTY ,
-.Nm STAILQ_ENTRY ,
-.Nm STAILQ_FIRST ,
-.Nm STAILQ_FOREACH ,
-.\" .Nm STAILQ_FOREACH_FROM ,
-.\" .Nm STAILQ_FOREACH_FROM_SAFE ,
-.\" .Nm STAILQ_FOREACH_SAFE ,
-.Nm STAILQ_HEAD ,
-.Nm STAILQ_HEAD_INITIALIZER ,
-.Nm STAILQ_INIT ,
-.Nm STAILQ_INSERT_AFTER ,
-.Nm STAILQ_INSERT_HEAD ,
-.Nm STAILQ_INSERT_TAIL ,
-.\" .Nm STAILQ_LAST ,
-.Nm STAILQ_NEXT ,
-.Nm STAILQ_REMOVE ,
-.\" .Nm STAILQ_REMOVE_AFTER ,
-.Nm STAILQ_REMOVE_HEAD ,
-.\" .Nm STAILQ_SWAP ,
+STAILQ_CONCAT,
+STAILQ_EMPTY,
+STAILQ_ENTRY,
+STAILQ_FIRST,
+STAILQ_FOREACH,
+.\"STAILQ_FOREACH_FROM,
+.\"STAILQ_FOREACH_FROM_SAFE,
+.\"STAILQ_FOREACH_SAFE,
+STAILQ_HEAD,
+STAILQ_HEAD_INITIALIZER,
+STAILQ_INIT,
+STAILQ_INSERT_AFTER,
+STAILQ_INSERT_HEAD,
+STAILQ_INSERT_TAIL,
+.\"STAILQ_LAST,
+STAILQ_NEXT,
+STAILQ_REMOVE,
+.\"STAILQ_REMOVE_AFTER,
+STAILQ_REMOVE_HEAD,
+.\"STAILQ_SWAP
.SH SYNOPSIS
-.In sys/queue.h
-.\"
-.Fn STAILQ_CONCAT "STAILQ_HEAD *head1" "STAILQ_HEAD *head2"
-.Fn STAILQ_EMPTY "STAILQ_HEAD *head"
-.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_FROM_SAFE "TYPE *var" "STAILQ_HEAD *head" "STAILQ_ENTRY NAME" "TYPE *temp_var"
-.\" .Fn STAILQ_FOREACH_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"
-.Fn STAILQ_INSERT_AFTER "STAILQ_HEAD *head" "TYPE *listelm" "TYPE *elm" "STAILQ_ENTRY NAME"
-.Fn STAILQ_INSERT_HEAD "STAILQ_HEAD *head" "TYPE *elm" "STAILQ_ENTRY NAME"
-.Fn STAILQ_INSERT_TAIL "STAILQ_HEAD *head" "TYPE *elm" "STAILQ_ENTRY NAME"
-.\" .Fn STAILQ_LAST "STAILQ_HEAD *head" "TYPE" "STAILQ_ENTRY NAME"
-.Fn STAILQ_NEXT "TYPE *elm" "STAILQ_ENTRY NAME"
-.Fn STAILQ_REMOVE "STAILQ_HEAD *head" "TYPE *elm" "TYPE" "STAILQ_ENTRY NAME"
-.\" .Fn STAILQ_REMOVE_AFTER "STAILQ_HEAD *head" "TYPE *elm" "STAILQ_ENTRY NAME"
-.Fn STAILQ_REMOVE_HEAD "STAILQ_HEAD *head" "STAILQ_ENTRY NAME"
-.\" .Fn STAILQ_SWAP "STAILQ_HEAD *head1" "STAILQ_HEAD *head2" "STAILQ_ENTRY NAME"
-.\"
+.nf
+.B #include <sys/queue.h>
+.PP
+.BI "void STAILQ_CONCAT(STAILQ_HEAD *" head1 ", STAILQ_HEAD *" head2 ");"
+.PP
+.BI "int STAILQ_EMPTY(STAILQ_HEAD *" head ");"
+.PP
+.B STAILQ_ENTRY(TYPE);
+.PP
+.BI "STAILQ_ENTRY *STAILQ_FIRST(STAILQ_HEAD *" head ");"
+.PP
+.BI "STAILQ_FOREACH(TYPE *" var ", STAILQ_HEAD *" head ", STAILQ_ENTRY " NAME ");"
+.\" .PP
+.\" .BI "STAILQ_FOREACH_FROM(TYPE *" var ", STAILQ_HEAD *" head ", STAILQ_ENTRY " NAME ");"
+.\" .PP
+.\" .BI "STAILQ_FOREACH_FROM_SAFE(TYPE *" var ", STAILQ_HEAD *" head ", STAILQ_ENTRY " NAME ", TYPE *" temp_var ");"
+.\" .PP
+.\" .BI "STAILQ_FOREACH_SAFE(TYPE *" var ", STAILQ_HEAD *" head ", STAILQ_ENTRY " NAME ", TYPE *" temp_var ");"
+.PP
+.B STAILQ_HEAD(HEADNAME, TYPE);
+.PP
+.BI "STAILQ_HEAD STAILQ_HEAD_INITIALIZER(STAILQ_HEAD " head ");"
+.PP
+.BI "void STAILQ_INIT(STAILQ_HEAD *" head ");"
+.PP
+.BI "void STAILQ_INSERT_AFTER(STAILQ_HEAD *" head ", TYPE *" listelm ", TYPE *" elm ","
+.BI " STAILQ_ENTRY " NAME ");"
+.PP
+.BI "void STAILQ_INSERT_HEAD(STAILQ_HEAD *" head ", TYPE *" elm ", STAILQ_ENTRY " NAME ");"
+.PP
+.BI "void STAILQ_INSERT_TAIL(STAILQ_HEAD *" head ", TYPE *" elm ", STAILQ_ENTRY " NAME ");"
+.\" .PP
+.\" .BI "STAILQ_ENTRY *STAILQ_LAST(STAILQ_HEAD *" head ", TYPE *" elm ", STAILQ_ENTRY " NAME ");"
+.PP
+.BI "STAILQ_ENTRY *STAILQ_NEXT(TYPE *" elm ", STAILQ_ENTRY " NAME ");"
+.PP
+.BI "void STAILQ_REMOVE(STAILQ_HEAD *" head ", TYPE *" elm ", TYPE,"
+.BI " STAILQ_ENTRY " NAME ");"
+.\" .PP
+.\" .BI "void STAILQ_REMOVE_AFTER(STAILQ_HEAD *" head ", TYPE *" elm ","
+.\" .BI " STAILQ_ENTRY " NAME ");"
+.PP
+.BI "void STAILQ_REMOVE_HEAD(STAILQ_HEAD *" head ", STAILQ_ENTRY " NAME ");"
+.\" .PP
+.\" .BI "void STAILQ_SWAP(STAILQ_HEAD *" head1 ", STAILQ_HEAD *" head2 ","
+.\" .BI " STAILQ_ENTRY " NAME ");"
+.fi
.SH DESCRIPTION
In the macro definitions,
-.Fa TYPE
+.I TYPE
is the name of a user-defined structure,
that must contain a field of type
-.Li STAILQ_ENTRY ,
+.IR STAILQ_ENTRY ,
named
-.Fa NAME .
+.IR NAME .
The argument
-.Fa HEADNAME
+.I HEADNAME
is the name of a user-defined structure that must be declared
using the macro
-.Li STAILQ_HEAD .
+.BR STAILQ_HEAD ().
.Ss Singly-linked tail queues
A singly-linked tail queue is headed by a structure defined by the
-.Nm STAILQ_HEAD
+.BR STAILQ_HEAD ()
macro.
This structure contains a pair of pointers,
one to the first element in the tail queue and the other to
@@ -101,177 +125,180 @@ elements.
New elements can be added to the tail queue after an existing element,
at the head of the tail queue, or at the end of the tail queue.
A
-.Fa STAILQ_HEAD
+.I STAILQ_HEAD
structure is declared as follows:
-.Bd -literal -offset indent
+.PP
+.in +4
+.EX
STAILQ_HEAD(HEADNAME, TYPE) head;
-.Ed
-.Pp
+.EE
+.in
+.PP
where
-.Li HEADNAME
+.I HEADNAME
is the name of the structure to be defined, and
-.Li TYPE
+.I TYPE
is the type of the elements to be linked into the tail queue.
A pointer to the head of the tail queue can later be declared as:
-.Bd -literal -offset indent
+.PP
+.in +4
+.EX
struct HEADNAME *headp;
-.Ed
-.Pp
+.EE
+.in
+.PP
(The names
-.Li head
+.I head
and
-.Li headp
+.I headp
are user selectable.)
-.Pp
+.PP
The macro
-.Nm STAILQ_HEAD_INITIALIZER
+.BR STAILQ_HEAD_INITIALIZER ()
evaluates to an initializer for the tail queue
-.Fa head .
-.Pp
+.IR head .
+.PP
The macro
-.Nm STAILQ_CONCAT
+.BR STAILQ_CONCAT ()
concatenates the tail queue headed by
-.Fa head2
+.I head2
onto the end of the one headed by
-.Fa head1
+.I head1
removing all entries from the former.
-.Pp
+.PP
The macro
-.Nm STAILQ_EMPTY
+.BR STAILQ_EMPTY ()
evaluates to true if there are no items on the tail queue.
-.Pp
+.PP
The macro
-.Nm STAILQ_ENTRY
+.BR STAILQ_ENTRY ()
declares a structure that connects the elements in
the tail queue.
-.Pp
+.PP
The macro
-.Nm STAILQ_FIRST
+.BR STAILQ_FIRST ()
returns the first item on the tail queue or NULL if the tail queue
is empty.
-.Pp
+.PP
The macro
-.Nm STAILQ_FOREACH
+.BR STAILQ_FOREACH ()
traverses the tail queue referenced by
-.Fa head
+.I head
in the forward direction, assigning each element
in turn to
-.Fa var .
-.\" .Pp
+.IR var .
+.\" .PP
.\" The macro
-.\" .Nm STAILQ_FOREACH_FROM
+.\" .BR STAILQ_FOREACH_FROM ()
.\" behaves identically to
-.\" .Nm STAILQ_FOREACH
+.\" .BR STAILQ_FOREACH ()
.\" when
-.\" .Fa var
+.\" .I var
.\" is NULL, else it treats
-.\" .Fa var
+.\" .I var
.\" as a previously found STAILQ element and begins the loop at
-.\" .Fa var
+.\" .I var
.\" instead of the first element in the STAILQ referenced by
-.\" .Fa head .
-.\" .Pp
+.\" .IR head .
+.\" .PP
.\" The macro
-.\" .Nm STAILQ_FOREACH_SAFE
+.\" .BR STAILQ_FOREACH_SAFE ()
.\" traverses the tail queue referenced by
-.\" .Fa head
+.\" .I head
.\" in the forward direction, assigning each element
.\" in turn to
-.\" .Fa var .
+.\" .IR var .
.\" However, unlike
-.\" .Fn STAILQ_FOREACH
+.\" .BR STAILQ_FOREACH ()
.\" here it is permitted to both remove
-.\" .Fa var
+.\" .I var
.\" as well as free it from within the loop safely without interfering with the
.\" traversal.
-.\" .Pp
+.\" .PP
.\" The macro
-.\" .Nm STAILQ_FOREACH_FROM_SAFE
+.\" .BR STAILQ_FOREACH_FROM_SAFE ()
.\" behaves identically to
-.\" .Nm STAILQ_FOREACH_SAFE
+.\" .BR STAILQ_FOREACH_SAFE ()
.\" when
-.\" .Fa var
+.\" .I var
.\" is NULL, else it treats
-.\" .Fa var
+.\" .I var
.\" as a previously found STAILQ element and begins the loop at
-.\" .Fa var
+.\" .I var
.\" instead of the first element in the STAILQ referenced by
-.\" .Fa head .
-.Pp
+.\" .IR head .
+.PP
The macro
-.Nm STAILQ_INIT
+.BR STAILQ_INIT ()
initializes the tail queue referenced by
-.Fa head .
-.Pp
+.IR head .
+.PP
The macro
-.Nm STAILQ_INSERT_HEAD
+.BR STAILQ_INSERT_HEAD ()
inserts the new element
-.Fa elm
+.I elm
at the head of the tail queue.
-.Pp
+.PP
The macro
-.Nm STAILQ_INSERT_TAIL
+.BR STAILQ_INSERT_TAIL ()
inserts the new element
-.Fa elm
+.I elm
at the end of the tail queue.
-.Pp
+.PP
The macro
-.Nm STAILQ_INSERT_AFTER
+.BR STAILQ_INSERT_AFTER ()
inserts the new element
-.Fa elm
+.I elm
after the element
-.Fa listelm .
-.\" .Pp
+.IR listelm .
+.\" .PP
.\" The macro
-.\" .Nm STAILQ_LAST
+.\" .BR STAILQ_LAST ()
.\" returns the last item on the tail queue.
-.\" If the tail queue is empty the return value is
-.\" .Dv NULL .
-.Pp
+.\" If the tail queue is empty the return value is NULL .
+.PP
The macro
-.Nm STAILQ_NEXT
+.BR STAILQ_NEXT ()
returns the next item on the tail queue, or NULL this item is the last.
-.\" .Pp
+.\" .PP
.\" The macro
-.\" .Nm STAILQ_REMOVE_AFTER
+.\" .BR STAILQ_REMOVE_AFTER ()
.\" removes the element after
-.\" .Fa elm
+.\" .I elm
.\" from the tail queue.
.\" Unlike
-.\" .Fa STAILQ_REMOVE ,
+.\" .BR STAILQ_REMOVE (),
.\" this macro does not traverse the entire tail queue.
-.Pp
+.PP
The macro
-.Nm STAILQ_REMOVE_HEAD
+.BR STAILQ_REMOVE_HEAD ()
removes the element at the head of the tail queue.
For optimum efficiency,
elements being removed from the head of the tail queue should
use this macro explicitly rather than the generic
-.Fa STAILQ_REMOVE
+.BR STAILQ_REMOVE ()
macro.
-.Pp
+.PP
The macro
-.Nm STAILQ_REMOVE
+.BR STAILQ_REMOVE ()
removes the element
-.Fa elm
+.I elm
from the tail queue.
-.\" .Pp
+.\" .PP
.\" The macro
-.\" .Nm STAILQ_SWAP
+.\" .BR STAILQ_SWAP ()
.\" swaps the contents of
-.\" .Fa head1
+.\" .I head1
.\" and
-.\" .Fa head2 .
+.\" .IR head2 .
.SH RETURN VALUE
.SH CONFORMING TO
Not in POSIX.1, POSIX.1-2001 or POSIX.1-2008.
Present on the BSDs
-(STAILQ macros first appeared in
-.Bx 4.4 ).
+(STAILQ macros first appeared in 4.4BSD).
.SH BUGS
.SH EXAMPLES
-.Ss Singly-linked tail queue example
-.Bd -literal
+.EX
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
@@ -279,7 +306,7 @@ Present on the BSDs
struct entry {
int data;
- STAILQ_ENTRY(entry) entries; /* Singly-linked tail queue. */
+ STAILQ_ENTRY(entry) entries; /* Singly-linked tail queue. */
};
STAILQ_HEAD(stailhead, entry);
@@ -288,25 +315,25 @@ int
main(void)
{
struct entry *n1, *n2, *n3, *np;
- struct stailhead head; /* Singly-linked tail queue
- head. */
+ struct stailhead head; /* Singly-linked tail queue
+ head. */
- STAILQ_INIT(&head); /* Initialize the queue. */
+ STAILQ_INIT(&head); /* Initialize the queue. */
- n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
+ n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
STAILQ_INSERT_HEAD(&head, n1, entries);
- n1 = malloc(sizeof(struct entry)); /* Insert at the tail. */
+ n1 = malloc(sizeof(struct entry)); /* Insert at the tail. */
STAILQ_INSERT_TAIL(&head, n1, entries);
- n2 = malloc(sizeof(struct entry)); /* Insert after. */
+ n2 = malloc(sizeof(struct entry)); /* Insert after. */
STAILQ_INSERT_AFTER(&head, n1, n2, entries);
STAILQ_REMOVE(&head, n2, entry, entries);/* Deletion. */
free(n2);
n3 = STAILQ_FIRST(&head);
- STAILQ_REMOVE_HEAD(&head, entries); /* Deletion from the head. */
+ STAILQ_REMOVE_HEAD(&head, entries); /* Deletion from the head. */
free(n3);
n1 = STAILQ_FIRST(&head);
@@ -316,10 +343,10 @@ main(void)
STAILQ_INSERT_HEAD(&head, n1, entries);
n1->data = i;
}
- /* Forward traversal. */
+ /* Forward traversal. */
STAILQ_FOREACH(np, &head, entries)
printf("%i\en", np->data);
- /* TailQ Deletion. */
+ /* TailQ Deletion. */
n1 = STAILQ_FIRST(&head);
while (n1 != NULL) {
n2 = STAILQ_NEXT(n1, entries);
@@ -330,5 +357,5 @@ main(void)
exit(EXIT_SUCCESS);
}
-.Ed
+.EE
.SH SEE ALSO