sys-queue.h revision 7c478bd95313f5f23a4c958a745db2134aa03244
/* $OpenBSD: queue.h,v 1.22 2001/06/23 04:39:35 angelos Exp $ */
/* $NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $ */
#ifndef _SYS_QUEUE_H
#define _SYS_QUEUE_H
#pragma ident "%Z%%M% %I% %E% SMI"
#ifdef __cplusplus
extern "C" {
#endif
/*
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)queue.h 8.5 (Berkeley) 8/20/94
*/
/*
* Ignore all <sys/queue.h> since older platforms have broken/incomplete
*/
/*
* This file defines five types of data structures: singly-linked lists,
* lists, simple queues, tail queues, and circular 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 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 only be traversed in the forward direction.
*
* A simple queue is headed by a pair of pointers, one the head of the
* list and the other to the tail of the list. The elements are singly
* linked to save space, so elements can only be removed from the
* head of the list. New elements can be added to the list before or after
* an existing element, at the head of the list, or at the end of the
* list. A simple queue may only be traversed in the forward 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
* 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, at the head of the list, or at the end of
* the list. A tail queue may be traversed in either direction.
*
* A circle 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
* 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, at the head of the list, or at the end of the list.
* A circle queue may be traversed in either direction, but has a more
* complex end of list detection.
*
* For details on the use of these macros, see the queue(3) manual page.
*/
/*
* Singly-linked List definitions.
*/
struct name { \
}
#define SLIST_HEAD_INITIALIZER(head) \
{ NULL }
#define SLIST_ENTRY(type) \
struct { \
}
/*
* Singly-linked List access methods.
*/
/*
* Singly-linked List functions.
*/
#define SLIST_INIT(head) { \
}
} while (0)
} while (0)
} while (0)
} \
else { \
} \
} while (0)
/*
* List definitions.
*/
struct name { \
}
#define LIST_HEAD_INITIALIZER(head) \
{ NULL }
#define LIST_ENTRY(type) \
struct { \
}
/*
* List access methods
*/
/*
* List functions.
*/
} while (0)
} while (0)
} while (0)
} while (0)
} while (0)
} while (0)
/*
* Simple queue definitions.
*/
struct name { \
}
#define SIMPLEQ_HEAD_INITIALIZER(head) \
#define SIMPLEQ_ENTRY(type) \
struct { \
}
/*
* Simple queue access methods.
*/
/*
* Simple queue functions.
*/
#define SIMPLEQ_INIT(head) do { \
} while (0)
} while (0)
} while (0)
} while (0)
} while (0)
/*
* Tail queue definitions.
*/
struct name { \
}
#define TAILQ_HEAD_INITIALIZER(head) \
#define TAILQ_ENTRY(type) \
struct { \
}
/*
* tail queue access methods
*/
/* XXX */
#define TAILQ_EMPTY(head) \
/*
* Tail queue functions.
*/
#define TAILQ_INIT(head) do { \
} while (0)
else \
} while (0)
} while (0)
else \
} while (0)
} while (0)
else \
} while (0)
else \
} while (0)
/*
* Circular queue definitions.
*/
struct name { \
}
#define CIRCLEQ_HEAD_INITIALIZER(head) \
#define CIRCLEQ_ENTRY(type) \
struct { \
}
/*
* Circular queue access methods
*/
#define CIRCLEQ_EMPTY(head) \
/*
* Circular queue functions.
*/
#define CIRCLEQ_INIT(head) do { \
} while (0)
else \
} while (0)
else \
} while (0)
else \
} while (0)
else \
} while (0)
else \
else \
} while (0)
CIRCLEQ_END(head)) \
else \
CIRCLEQ_END(head)) \
else \
} while (0)
#ifdef __cplusplus
}
#endif
#endif /* _SYS_QUEUE_H */