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Diffstat (limited to 'slirp/qtailq.h')
| -rw-r--r-- | slirp/qtailq.h | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/slirp/qtailq.h b/slirp/qtailq.h new file mode 100644 index 0000000000..a89b0c439a --- /dev/null +++ b/slirp/qtailq.h @@ -0,0 +1,193 @@ +/* $NetBSD: queue.h,v 1.52 2009/04/20 09:56:08 mschuett Exp $ */ + +/* + * slirp version: Copy from QEMU, removed all but tail queues. + */ + +/* + * 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 + * documentation and/or other materials provided with the distribution. + * 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. + * + * 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 + */ + +#ifndef QTAILQ_H +#define QTAILQ_H + +/* + * 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. + */ +typedef struct QTailQLink { + void *tql_next; + struct QTailQLink *tql_prev; +} QTailQLink; + +/* + * Tail queue definitions. The union acts as a poor man template, as if + * it were QTailQLink<type>. + */ +#define QTAILQ_HEAD(name, type) \ + union name { \ + struct type *tqh_first; /* first element */ \ + QTailQLink tqh_circ; /* link for circular backwards list */ \ + } + +#define QTAILQ_HEAD_INITIALIZER(head) \ + { .tqh_circ = { NULL, &(head).tqh_circ } } + +#define QTAILQ_ENTRY(type) \ + union { \ + struct type *tqe_next; /* next element */ \ + QTailQLink tqe_circ; /* link for circular backwards list */ \ + } + +#define QTAILQ_INIT(head) do { \ + (head)->tqh_first = NULL; \ + (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_circ.tql_prev = \ + &(elm)->field.tqe_circ; \ + else \ + (head)->tqh_circ.tql_prev = &(elm)->field.tqe_circ; \ + (head)->tqh_first = (elm); \ + (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_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_circ.tql_prev = \ + &(elm)->field.tqe_circ; \ + else \ + (head)->tqh_circ.tql_prev = &(elm)->field.tqe_circ; \ + (listelm)->field.tqe_next = (elm); \ + (elm)->field.tqe_circ.tql_prev = &(listelm)->field.tqe_circ; \ +} while (/*CONSTCOND*/0) + +#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_circ.tql_prev = \ + (elm)->field.tqe_circ.tql_prev; \ + else \ + (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) \ + for ((var) = ((head)->tqh_first); \ + (var); \ + (var) = ((var)->field.tqe_next)) + +#define QTAILQ_FOREACH_SAFE(var, head, field, next_var) \ + for ((var) = ((head)->tqh_first); \ + (var) && ((next_var) = ((var)->field.tqe_next), 1); \ + (var) = (next_var)) + +#define QTAILQ_FOREACH_REVERSE(var, head, field) \ + for ((var) = QTAILQ_LAST(head); \ + (var); \ + (var) = QTAILQ_PREV(var, field)) + +#define QTAILQ_FOREACH_REVERSE_SAFE(var, head, field, prev_var) \ + for ((var) = QTAILQ_LAST(head); \ + (var) && ((prev_var) = QTAILQ_PREV(var, field)); \ + (var) = (prev_var)) + +/* + * Tail queue access methods. + */ +#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_circ.tql_prev != NULL) + +#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))) + +/* + * 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, 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, void *) +#define QTAILQ_RAW_TQE_CIRC(elm, entry) \ + field_at_offset(elm, entry, QTailQLink) +/* + * Tail queue traversal using pointer arithmetic. + */ +#define QTAILQ_RAW_FOREACH(elm, head, entry) \ + for ((elm) = *QTAILQ_RAW_FIRST(head); \ + (elm); \ + (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_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 /* QTAILQ_H */ |