path: root/contrib/tools/yasm/libyasm/compat-queue.h

/* 
 * <sys/queue.h> implementation for systems that don't have it. 
 * 
 * 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 
 * $FreeBSD: src/sys/sys/queue.h,v 1.32.2.4 2001/03/31 03:33:39 hsu Exp $ 
 */ 
 
#ifndef SYS_QUEUE_H 
#define SYS_QUEUE_H 
 
/* 
 * 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 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. 
 * 
 * For details on the use of these macros, see the queue(3) manual page. 
 * 
 * 
 *                              SLIST   LIST    STAILQ  TAILQ 
 * _HEAD                        +       +       +       + 
 * _HEAD_INITIALIZER            +       +       +       + 
 * _ENTRY                       +       +       +       + 
 * _INIT                        +       +       +       + 
 * _EMPTY                       +       +       +       + 
 * _FIRST                       +       +       +       + 
 * _NEXT                        +       +       +       + 
 * _PREV                        -       -       -       + 
 * _LAST                        -       -       +       + 
 * _FOREACH                     +       +       +       + 
 * _FOREACH_SAFE                +       +       +       + 
 * _FOREACH_REVERSE             -       -       -       + 
 * _FOREACH_REVERSE_SAFE        -       -       -       + 
 * _INSERT_HEAD                 +       +       +       + 
 * _INSERT_BEFORE               -       +       -       + 
 * _INSERT_AFTER                +       +       +       + 
 * _INSERT_TAIL                 -       -       +       + 
 * _CONCAT                      -       -       +       + 
 * _REMOVE_HEAD                 +       -       +       - 
 * _REMOVE                      +       +       +       + 
 * 
 */ 
 
/* 
 * Singly-linked List declarations. 
 */ 
#define SLIST_HEAD(name, type)                                          \ 
struct name {                                                           \ 
        struct type *slh_first; /* first element */                     \ 
} 
 
#define SLIST_HEAD_INITIALIZER(head)                                    \ 
        { NULL } 
 
#define SLIST_ENTRY(type)                                               \ 
struct {                                                                \ 
        struct type *sle_next;  /* next element */                      \ 
} 
 
/* 
 * Singly-linked List functions. 
 */ 
#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_SAFE(var, head, field, tvar)                      \ 
        for ((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 {                       \ 
        if (SLIST_FIRST((head)) == (elm)) {                             \ 
                SLIST_REMOVE_HEAD((head), field);                       \ 
        }                                                               \ 
        else {                                                          \ 
                struct type *curelm = SLIST_FIRST((head));              \ 
                while (SLIST_NEXT(curelm, field) != (elm))              \ 
                        curelm = SLIST_NEXT(curelm, field);             \ 
                SLIST_NEXT(curelm, field) =                             \ 
                    SLIST_NEXT(SLIST_NEXT(curelm, field), field);       \ 
        }                                                               \ 
} while (0) 
 
#define SLIST_REMOVE_HEAD(head, field) do {                             \ 
        SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field);   \ 
} 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_HEAD_INITIALIZER(head)                                   \ 
        { NULL, &(head).stqh_first } 
 
#define STAILQ_ENTRY(type)                                              \ 
struct {                                                                \ 
        struct 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_SAFE(var, head, field, tvar)                     \ 
        for ((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 :                                                  \ 
                ((struct type *)                                        \ 
                ((char *)((head)->stqh_last) - offsetof(struct type, field)))) 
 
#define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next) 
 
#define STAILQ_REMOVE(head, elm, type, field) do {                      \ 
        if (STAILQ_FIRST((head)) == (elm)) {                            \ 
                STAILQ_REMOVE_HEAD((head), field);                      \ 
        }                                                               \ 
        else {                                                          \ 
                struct type *curelm = STAILQ_FIRST((head));             \ 
                while (STAILQ_NEXT(curelm, field) != (elm))             \ 
                        curelm = STAILQ_NEXT(curelm, field);            \ 
                if ((STAILQ_NEXT(curelm, field) =                       \ 
                     STAILQ_NEXT(STAILQ_NEXT(curelm, field), field)) == NULL)\ 
                        (head)->stqh_last = &STAILQ_NEXT((curelm), 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_REMOVE_HEAD_UNTIL(head, elm, field) do {                 \ 
        if ((STAILQ_FIRST((head)) = STAILQ_NEXT((elm), field)) == NULL) \ 
                (head)->stqh_last = &STAILQ_FIRST((head));              \ 
} while (0) 
 
/* 
 * List declarations. 
 */ 
#define LIST_HEAD(name, type)                                           \ 
struct name {                                                           \ 
        struct 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 */  \ 
} 
 
/* 
 * List functions. 
 */ 
 
#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_SAFE(var, head, field, tvar)                       \ 
        for ((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 {                     \ 
        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 {                    \ 
        (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 {                         \ 
        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_REMOVE(elm, field) do {                                    \ 
        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);                \ 
} while (0) 
 
/* 
 * Tail queue declarations. 
 */ 
#define TAILQ_HEAD(name, type)                                          \ 
struct name {                                                           \ 
        struct type *tqh_first; /* first element */                     \ 
        struct type **tqh_last; /* addr of last next element */         \ 
} 
 
#define TAILQ_HEAD_INITIALIZER(head)                                    \ 
        { NULL, &(head).tqh_first } 
 
#define TAILQ_ENTRY(type)                                               \ 
struct {                                                                \ 
        struct type *tqe_next;  /* next element */                      \ 
        struct type **tqe_prev; /* address of previous next element */  \ 
} 
 
/* 
 * Tail queue functions. 
 */ 
#define TAILQ_CONCAT(head1, head2, field) do {                          \ 
        if (!TAILQ_EMPTY(head2)) {                                      \ 
                *(head1)->tqh_last = (head2)->tqh_first;                \ 
                (head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \ 
                (head1)->tqh_last = (head2)->tqh_last;                  \ 
                TAILQ_INIT((head2));                                    \ 
        }                                                               \ 
} while (0) 
 
#define TAILQ_EMPTY(head)       ((head)->tqh_first == NULL) 
 
#define TAILQ_FIRST(head)       ((head)->tqh_first) 
 
#define TAILQ_FOREACH(var, head, field)                                 \ 
        for ((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_REVERSE(var, head, headname, field)               \ 
        for ((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_INIT(head) do {                                           \ 
        TAILQ_FIRST((head)) = NULL;                                     \ 
        (head)->tqh_last = &TAILQ_FIRST((head));                        \ 
} while (0) 
 
#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do {              \ 
        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);           \ 
        }                                                               \ 
        TAILQ_NEXT((listelm), field) = (elm);                           \ 
        (elm)->field.tqe_prev = &TAILQ_NEXT((listelm), field);          \ 
} while (0) 
 
#define TAILQ_INSERT_BEFORE(listelm, elm, field) do {                   \ 
        (elm)->field.tqe_prev = (listelm)->field.tqe_prev;              \ 
        TAILQ_NEXT((elm), field) = (listelm);                           \ 
        *(listelm)->field.tqe_prev = (elm);                             \ 
        (listelm)->field.tqe_prev = &TAILQ_NEXT((elm), field);          \ 
} while (0) 
 
#define TAILQ_INSERT_HEAD(head, elm, field) do {                        \ 
        if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL)   \ 
                TAILQ_FIRST((head))->field.tqe_prev =                   \ 
                    &TAILQ_NEXT((elm), field);                          \ 
        else                                                            \ 
                (head)->tqh_last = &TAILQ_NEXT((elm), field);           \ 
        TAILQ_FIRST((head)) = (elm);                                    \ 
        (elm)->field.tqe_prev = &TAILQ_FIRST((head));                   \ 
} while (0) 
 
#define TAILQ_INSERT_TAIL(head, elm, field) do {                        \ 
        TAILQ_NEXT((elm), field) = NULL;                                \ 
        (elm)->field.tqe_prev = (head)->tqh_last;                       \ 
        *(head)->tqh_last = (elm);                                      \ 
        (head)->tqh_last = &TAILQ_NEXT((elm), field);                   \ 
} while (0) 
 
#define TAILQ_LAST(head, headname)                                      \ 
        (*(((struct headname *)((head)->tqh_last))->tqh_last)) 
 
#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_REMOVE(head, elm, field) do {                             \ 
        if ((TAILQ_NEXT((elm), field)) != NULL)                         \ 
                TAILQ_NEXT((elm), field)->field.tqe_prev =              \ 
                    (elm)->field.tqe_prev;                              \ 
        else {                                                          \ 
                (head)->tqh_last = (elm)->field.tqe_prev;               \ 
        }                                                               \ 
        *(elm)->field.tqe_prev = TAILQ_NEXT((elm), field);              \ 
} while (0) 
 
#endif /* !SYS_QUEUE_H */