File:  [Qemu by Fabrice Bellard] / qemu / qemu-queue.h
Revision 1.1.1.1 (vendor branch): download - view: text, annotated - select for diffs
Tue Apr 24 17:34:34 2018 UTC (3 years, 3 months ago) by root
Branches: qemu, MAIN
CVS tags: qemu1000, qemu0151, qemu0150, qemu0141, qemu0140, qemu0130, qemu0125, qemu0124, qemu0123, qemu0122, qemu0121, qemu0120, HEAD
qemu 0.12.0

    1: /*      $NetBSD: queue.h,v 1.52 2009/04/20 09:56:08 mschuett Exp $ */
    2: 
    3: /*
    4:  * Qemu version: Copy from netbsd, removed debug code, removed some of
    5:  * the implementations.  Left in lists, simple queues, tail queues and
    6:  * circular queues.
    7:  */
    8: 
    9: /*
   10:  * Copyright (c) 1991, 1993
   11:  *      The Regents of the University of California.  All rights reserved.
   12:  *
   13:  * Redistribution and use in source and binary forms, with or without
   14:  * modification, are permitted provided that the following conditions
   15:  * are met:
   16:  * 1. Redistributions of source code must retain the above copyright
   17:  *    notice, this list of conditions and the following disclaimer.
   18:  * 2. Redistributions in binary form must reproduce the above copyright
   19:  *    notice, this list of conditions and the following disclaimer in the
   20:  *    documentation and/or other materials provided with the distribution.
   21:  * 3. Neither the name of the University nor the names of its contributors
   22:  *    may be used to endorse or promote products derived from this software
   23:  *    without specific prior written permission.
   24:  *
   25:  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   26:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   27:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   28:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   29:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   30:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   31:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   32:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   33:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   34:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   35:  * SUCH DAMAGE.
   36:  *
   37:  *      @(#)queue.h     8.5 (Berkeley) 8/20/94
   38:  */
   39: 
   40: #ifndef QEMU_SYS_QUEUE_H_
   41: #define QEMU_SYS_QUEUE_H_
   42: 
   43: /*
   44:  * This file defines four types of data structures:
   45:  * lists, simple queues, tail queues, and circular queues.
   46:  *
   47:  * A list is headed by a single forward pointer (or an array of forward
   48:  * pointers for a hash table header). The elements are doubly linked
   49:  * so that an arbitrary element can be removed without a need to
   50:  * traverse the list. New elements can be added to the list before
   51:  * or after an existing element or at the head of the list. A list
   52:  * may only be traversed in the forward direction.
   53:  *
   54:  * A simple queue is headed by a pair of pointers, one the head of the
   55:  * list and the other to the tail of the list. The elements are singly
   56:  * linked to save space, so elements can only be removed from the
   57:  * head of the list. New elements can be added to the list after
   58:  * an existing element, at the head of the list, or at the end of the
   59:  * list. A simple queue may only be traversed in the forward direction.
   60:  *
   61:  * A tail queue is headed by a pair of pointers, one to the head of the
   62:  * list and the other to the tail of the list. The elements are doubly
   63:  * linked so that an arbitrary element can be removed without a need to
   64:  * traverse the list. New elements can be added to the list before or
   65:  * after an existing element, at the head of the list, or at the end of
   66:  * the list. A tail queue may be traversed in either direction.
   67:  *
   68:  * A circle queue is headed by a pair of pointers, one to the head of the
   69:  * list and the other to the tail of the list. The elements are doubly
   70:  * linked so that an arbitrary element can be removed without a need to
   71:  * traverse the list. New elements can be added to the list before or after
   72:  * an existing element, at the head of the list, or at the end of the list.
   73:  * A circle queue may be traversed in either direction, but has a more
   74:  * complex end of list detection.
   75:  *
   76:  * For details on the use of these macros, see the queue(3) manual page.
   77:  */
   78: 
   79: /*
   80:  * List definitions.
   81:  */
   82: #define QLIST_HEAD(name, type)                                          \
   83: struct name {                                                           \
   84:         struct type *lh_first;  /* first element */                     \
   85: }
   86: 
   87: #define QLIST_HEAD_INITIALIZER(head)                                    \
   88:         { NULL }
   89: 
   90: #define QLIST_ENTRY(type)                                               \
   91: struct {                                                                \
   92:         struct type *le_next;   /* next element */                      \
   93:         struct type **le_prev;  /* address of previous next element */  \
   94: }
   95: 
   96: /*
   97:  * List functions.
   98:  */
   99: #define QLIST_INIT(head) do {                                           \
  100:         (head)->lh_first = NULL;                                        \
  101: } while (/*CONSTCOND*/0)
  102: 
  103: #define QLIST_INSERT_AFTER(listelm, elm, field) do {                    \
  104:         if (((elm)->field.le_next = (listelm)->field.le_next) != NULL)  \
  105:                 (listelm)->field.le_next->field.le_prev =               \
  106:                     &(elm)->field.le_next;                              \
  107:         (listelm)->field.le_next = (elm);                               \
  108:         (elm)->field.le_prev = &(listelm)->field.le_next;               \
  109: } while (/*CONSTCOND*/0)
  110: 
  111: #define QLIST_INSERT_BEFORE(listelm, elm, field) do {                   \
  112:         (elm)->field.le_prev = (listelm)->field.le_prev;                \
  113:         (elm)->field.le_next = (listelm);                               \
  114:         *(listelm)->field.le_prev = (elm);                              \
  115:         (listelm)->field.le_prev = &(elm)->field.le_next;               \
  116: } while (/*CONSTCOND*/0)
  117: 
  118: #define QLIST_INSERT_HEAD(head, elm, field) do {                        \
  119:         if (((elm)->field.le_next = (head)->lh_first) != NULL)          \
  120:                 (head)->lh_first->field.le_prev = &(elm)->field.le_next;\
  121:         (head)->lh_first = (elm);                                       \
  122:         (elm)->field.le_prev = &(head)->lh_first;                       \
  123: } while (/*CONSTCOND*/0)
  124: 
  125: #define QLIST_REMOVE(elm, field) do {                                   \
  126:         if ((elm)->field.le_next != NULL)                               \
  127:                 (elm)->field.le_next->field.le_prev =                   \
  128:                     (elm)->field.le_prev;                               \
  129:         *(elm)->field.le_prev = (elm)->field.le_next;                   \
  130: } while (/*CONSTCOND*/0)
  131: 
  132: #define QLIST_FOREACH(var, head, field)                                 \
  133:         for ((var) = ((head)->lh_first);                                \
  134:                 (var);                                                  \
  135:                 (var) = ((var)->field.le_next))
  136: 
  137: #define QLIST_FOREACH_SAFE(var, head, field, next_var)                  \
  138:         for ((var) = ((head)->lh_first);                                \
  139:                 (var) && ((next_var) = ((var)->field.le_next), 1);      \
  140:                 (var) = (next_var))
  141: 
  142: /*
  143:  * List access methods.
  144:  */
  145: #define QLIST_EMPTY(head)                ((head)->lh_first == NULL)
  146: #define QLIST_FIRST(head)                ((head)->lh_first)
  147: #define QLIST_NEXT(elm, field)           ((elm)->field.le_next)
  148: 
  149: 
  150: /*
  151:  * Simple queue definitions.
  152:  */
  153: #define QSIMPLEQ_HEAD(name, type)                                       \
  154: struct name {                                                           \
  155:     struct type *sqh_first;    /* first element */                      \
  156:     struct type **sqh_last;    /* addr of last next element */          \
  157: }
  158: 
  159: #define QSIMPLEQ_HEAD_INITIALIZER(head)                                 \
  160:     { NULL, &(head).sqh_first }
  161: 
  162: #define QSIMPLEQ_ENTRY(type)                                            \
  163: struct {                                                                \
  164:     struct type *sqe_next;    /* next element */                        \
  165: }
  166: 
  167: /*
  168:  * Simple queue functions.
  169:  */
  170: #define QSIMPLEQ_INIT(head) do {                                        \
  171:     (head)->sqh_first = NULL;                                           \
  172:     (head)->sqh_last = &(head)->sqh_first;                              \
  173: } while (/*CONSTCOND*/0)
  174: 
  175: #define QSIMPLEQ_INSERT_HEAD(head, elm, field) do {                     \
  176:     if (((elm)->field.sqe_next = (head)->sqh_first) == NULL)            \
  177:         (head)->sqh_last = &(elm)->field.sqe_next;                      \
  178:     (head)->sqh_first = (elm);                                          \
  179: } while (/*CONSTCOND*/0)
  180: 
  181: #define QSIMPLEQ_INSERT_TAIL(head, elm, field) do {                     \
  182:     (elm)->field.sqe_next = NULL;                                       \
  183:     *(head)->sqh_last = (elm);                                          \
  184:     (head)->sqh_last = &(elm)->field.sqe_next;                          \
  185: } while (/*CONSTCOND*/0)
  186: 
  187: #define QSIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do {           \
  188:     if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)    \
  189:         (head)->sqh_last = &(elm)->field.sqe_next;                      \
  190:     (listelm)->field.sqe_next = (elm);                                  \
  191: } while (/*CONSTCOND*/0)
  192: 
  193: #define QSIMPLEQ_REMOVE_HEAD(head, field) do {                          \
  194:     if (((head)->sqh_first = (head)->sqh_first->field.sqe_next) == NULL)\
  195:         (head)->sqh_last = &(head)->sqh_first;                          \
  196: } while (/*CONSTCOND*/0)
  197: 
  198: #define QSIMPLEQ_REMOVE(head, elm, type, field) do {                    \
  199:     if ((head)->sqh_first == (elm)) {                                   \
  200:         QSIMPLEQ_REMOVE_HEAD((head), field);                            \
  201:     } else {                                                            \
  202:         struct type *curelm = (head)->sqh_first;                        \
  203:         while (curelm->field.sqe_next != (elm))                         \
  204:             curelm = curelm->field.sqe_next;                            \
  205:         if ((curelm->field.sqe_next =                                   \
  206:             curelm->field.sqe_next->field.sqe_next) == NULL)            \
  207:                 (head)->sqh_last = &(curelm)->field.sqe_next;           \
  208:     }                                                                   \
  209: } while (/*CONSTCOND*/0)
  210: 
  211: #define QSIMPLEQ_FOREACH(var, head, field)                              \
  212:     for ((var) = ((head)->sqh_first);                                   \
  213:         (var);                                                          \
  214:         (var) = ((var)->field.sqe_next))
  215: 
  216: #define QSIMPLEQ_FOREACH_SAFE(var, head, field, next)                   \
  217:     for ((var) = ((head)->sqh_first);                                   \
  218:         (var) && ((next = ((var)->field.sqe_next)), 1);                 \
  219:         (var) = (next))
  220: 
  221: #define QSIMPLEQ_CONCAT(head1, head2) do {                              \
  222:     if (!QSIMPLEQ_EMPTY((head2))) {                                     \
  223:         *(head1)->sqh_last = (head2)->sqh_first;                        \
  224:         (head1)->sqh_last = (head2)->sqh_last;                          \
  225:         QSIMPLEQ_INIT((head2));                                         \
  226:     }                                                                   \
  227: } while (/*CONSTCOND*/0)
  228: 
  229: #define QSIMPLEQ_LAST(head, type, field)                                \
  230:     (QSIMPLEQ_EMPTY((head)) ?                                           \
  231:         NULL :                                                          \
  232:             ((struct type *)(void *)                                    \
  233:         ((char *)((head)->sqh_last) - offsetof(struct type, field))))
  234: 
  235: /*
  236:  * Simple queue access methods.
  237:  */
  238: #define QSIMPLEQ_EMPTY(head)        ((head)->sqh_first == NULL)
  239: #define QSIMPLEQ_FIRST(head)        ((head)->sqh_first)
  240: #define QSIMPLEQ_NEXT(elm, field)   ((elm)->field.sqe_next)
  241: 
  242: 
  243: /*
  244:  * Tail queue definitions.
  245:  */
  246: #define Q_TAILQ_HEAD(name, type, qual)                                  \
  247: struct name {                                                           \
  248:         qual type *tqh_first;           /* first element */             \
  249:         qual type *qual *tqh_last;      /* addr of last next element */ \
  250: }
  251: #define QTAILQ_HEAD(name, type)  Q_TAILQ_HEAD(name, struct type,)
  252: 
  253: #define QTAILQ_HEAD_INITIALIZER(head)                                   \
  254:         { NULL, &(head).tqh_first }
  255: 
  256: #define Q_TAILQ_ENTRY(type, qual)                                       \
  257: struct {                                                                \
  258:         qual type *tqe_next;            /* next element */              \
  259:         qual type *qual *tqe_prev;      /* address of previous next element */\
  260: }
  261: #define QTAILQ_ENTRY(type)       Q_TAILQ_ENTRY(struct type,)
  262: 
  263: /*
  264:  * Tail queue functions.
  265:  */
  266: #define QTAILQ_INIT(head) do {                                          \
  267:         (head)->tqh_first = NULL;                                       \
  268:         (head)->tqh_last = &(head)->tqh_first;                          \
  269: } while (/*CONSTCOND*/0)
  270: 
  271: #define QTAILQ_INSERT_HEAD(head, elm, field) do {                       \
  272:         if (((elm)->field.tqe_next = (head)->tqh_first) != NULL)        \
  273:                 (head)->tqh_first->field.tqe_prev =                     \
  274:                     &(elm)->field.tqe_next;                             \
  275:         else                                                            \
  276:                 (head)->tqh_last = &(elm)->field.tqe_next;              \
  277:         (head)->tqh_first = (elm);                                      \
  278:         (elm)->field.tqe_prev = &(head)->tqh_first;                     \
  279: } while (/*CONSTCOND*/0)
  280: 
  281: #define QTAILQ_INSERT_TAIL(head, elm, field) do {                       \
  282:         (elm)->field.tqe_next = NULL;                                   \
  283:         (elm)->field.tqe_prev = (head)->tqh_last;                       \
  284:         *(head)->tqh_last = (elm);                                      \
  285:         (head)->tqh_last = &(elm)->field.tqe_next;                      \
  286: } while (/*CONSTCOND*/0)
  287: 
  288: #define QTAILQ_INSERT_AFTER(head, listelm, elm, field) do {             \
  289:         if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\
  290:                 (elm)->field.tqe_next->field.tqe_prev =                 \
  291:                     &(elm)->field.tqe_next;                             \
  292:         else                                                            \
  293:                 (head)->tqh_last = &(elm)->field.tqe_next;              \
  294:         (listelm)->field.tqe_next = (elm);                              \
  295:         (elm)->field.tqe_prev = &(listelm)->field.tqe_next;             \
  296: } while (/*CONSTCOND*/0)
  297: 
  298: #define QTAILQ_INSERT_BEFORE(listelm, elm, field) do {                  \
  299:         (elm)->field.tqe_prev = (listelm)->field.tqe_prev;              \
  300:         (elm)->field.tqe_next = (listelm);                              \
  301:         *(listelm)->field.tqe_prev = (elm);                             \
  302:         (listelm)->field.tqe_prev = &(elm)->field.tqe_next;             \
  303: } while (/*CONSTCOND*/0)
  304: 
  305: #define QTAILQ_REMOVE(head, elm, field) do {                            \
  306:         if (((elm)->field.tqe_next) != NULL)                            \
  307:                 (elm)->field.tqe_next->field.tqe_prev =                 \
  308:                     (elm)->field.tqe_prev;                              \
  309:         else                                                            \
  310:                 (head)->tqh_last = (elm)->field.tqe_prev;               \
  311:         *(elm)->field.tqe_prev = (elm)->field.tqe_next;                 \
  312: } while (/*CONSTCOND*/0)
  313: 
  314: #define QTAILQ_FOREACH(var, head, field)                                \
  315:         for ((var) = ((head)->tqh_first);                               \
  316:                 (var);                                                  \
  317:                 (var) = ((var)->field.tqe_next))
  318: 
  319: #define QTAILQ_FOREACH_SAFE(var, head, field, next_var)                 \
  320:         for ((var) = ((head)->tqh_first);                               \
  321:                 (var) && ((next_var) = ((var)->field.tqe_next), 1);     \
  322:                 (var) = (next_var))
  323: 
  324: #define QTAILQ_FOREACH_REVERSE(var, head, headname, field)              \
  325:         for ((var) = (*(((struct headname *)((head)->tqh_last))->tqh_last));    \
  326:                 (var);                                                  \
  327:                 (var) = (*(((struct headname *)((var)->field.tqe_prev))->tqh_last)))
  328: 
  329: /*
  330:  * Tail queue access methods.
  331:  */
  332: #define QTAILQ_EMPTY(head)               ((head)->tqh_first == NULL)
  333: #define QTAILQ_FIRST(head)               ((head)->tqh_first)
  334: #define QTAILQ_NEXT(elm, field)          ((elm)->field.tqe_next)
  335: 
  336: #define QTAILQ_LAST(head, headname) \
  337:         (*(((struct headname *)((head)->tqh_last))->tqh_last))
  338: #define QTAILQ_PREV(elm, headname, field) \
  339:         (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
  340: 
  341: 
  342: /*
  343:  * Circular queue definitions.
  344:  */
  345: #define QCIRCLEQ_HEAD(name, type)                                       \
  346: struct name {                                                           \
  347:         struct type *cqh_first;         /* first element */             \
  348:         struct type *cqh_last;          /* last element */              \
  349: }
  350: 
  351: #define QCIRCLEQ_HEAD_INITIALIZER(head)                                 \
  352:         { (void *)&head, (void *)&head }
  353: 
  354: #define QCIRCLEQ_ENTRY(type)                                            \
  355: struct {                                                                \
  356:         struct type *cqe_next;          /* next element */              \
  357:         struct type *cqe_prev;          /* previous element */          \
  358: }
  359: 
  360: /*
  361:  * Circular queue functions.
  362:  */
  363: #define QCIRCLEQ_INIT(head) do {                                        \
  364:         (head)->cqh_first = (void *)(head);                             \
  365:         (head)->cqh_last = (void *)(head);                              \
  366: } while (/*CONSTCOND*/0)
  367: 
  368: #define QCIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do {           \
  369:         (elm)->field.cqe_next = (listelm)->field.cqe_next;              \
  370:         (elm)->field.cqe_prev = (listelm);                              \
  371:         if ((listelm)->field.cqe_next == (void *)(head))                \
  372:                 (head)->cqh_last = (elm);                               \
  373:         else                                                            \
  374:                 (listelm)->field.cqe_next->field.cqe_prev = (elm);      \
  375:         (listelm)->field.cqe_next = (elm);                              \
  376: } while (/*CONSTCOND*/0)
  377: 
  378: #define QCIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do {          \
  379:         (elm)->field.cqe_next = (listelm);                              \
  380:         (elm)->field.cqe_prev = (listelm)->field.cqe_prev;              \
  381:         if ((listelm)->field.cqe_prev == (void *)(head))                \
  382:                 (head)->cqh_first = (elm);                              \
  383:         else                                                            \
  384:                 (listelm)->field.cqe_prev->field.cqe_next = (elm);      \
  385:         (listelm)->field.cqe_prev = (elm);                              \
  386: } while (/*CONSTCOND*/0)
  387: 
  388: #define QCIRCLEQ_INSERT_HEAD(head, elm, field) do {                     \
  389:         (elm)->field.cqe_next = (head)->cqh_first;                      \
  390:         (elm)->field.cqe_prev = (void *)(head);                         \
  391:         if ((head)->cqh_last == (void *)(head))                         \
  392:                 (head)->cqh_last = (elm);                               \
  393:         else                                                            \
  394:                 (head)->cqh_first->field.cqe_prev = (elm);              \
  395:         (head)->cqh_first = (elm);                                      \
  396: } while (/*CONSTCOND*/0)
  397: 
  398: #define QCIRCLEQ_INSERT_TAIL(head, elm, field) do {                     \
  399:         (elm)->field.cqe_next = (void *)(head);                         \
  400:         (elm)->field.cqe_prev = (head)->cqh_last;                       \
  401:         if ((head)->cqh_first == (void *)(head))                        \
  402:                 (head)->cqh_first = (elm);                              \
  403:         else                                                            \
  404:                 (head)->cqh_last->field.cqe_next = (elm);               \
  405:         (head)->cqh_last = (elm);                                       \
  406: } while (/*CONSTCOND*/0)
  407: 
  408: #define QCIRCLEQ_REMOVE(head, elm, field) do {                          \
  409:         if ((elm)->field.cqe_next == (void *)(head))                    \
  410:                 (head)->cqh_last = (elm)->field.cqe_prev;               \
  411:         else                                                            \
  412:                 (elm)->field.cqe_next->field.cqe_prev =                 \
  413:                     (elm)->field.cqe_prev;                              \
  414:         if ((elm)->field.cqe_prev == (void *)(head))                    \
  415:                 (head)->cqh_first = (elm)->field.cqe_next;              \
  416:         else                                                            \
  417:                 (elm)->field.cqe_prev->field.cqe_next =                 \
  418:                     (elm)->field.cqe_next;                              \
  419: } while (/*CONSTCOND*/0)
  420: 
  421: #define QCIRCLEQ_FOREACH(var, head, field)                              \
  422:         for ((var) = ((head)->cqh_first);                               \
  423:                 (var) != (const void *)(head);                          \
  424:                 (var) = ((var)->field.cqe_next))
  425: 
  426: #define QCIRCLEQ_FOREACH_REVERSE(var, head, field)                      \
  427:         for ((var) = ((head)->cqh_last);                                \
  428:                 (var) != (const void *)(head);                          \
  429:                 (var) = ((var)->field.cqe_prev))
  430: 
  431: /*
  432:  * Circular queue access methods.
  433:  */
  434: #define QCIRCLEQ_EMPTY(head)             ((head)->cqh_first == (void *)(head))
  435: #define QCIRCLEQ_FIRST(head)             ((head)->cqh_first)
  436: #define QCIRCLEQ_LAST(head)              ((head)->cqh_last)
  437: #define QCIRCLEQ_NEXT(elm, field)        ((elm)->field.cqe_next)
  438: #define QCIRCLEQ_PREV(elm, field)        ((elm)->field.cqe_prev)
  439: 
  440: #define QCIRCLEQ_LOOP_NEXT(head, elm, field)                            \
  441:         (((elm)->field.cqe_next == (void *)(head))                      \
  442:             ? ((head)->cqh_first)                                       \
  443:             : (elm->field.cqe_next))
  444: #define QCIRCLEQ_LOOP_PREV(head, elm, field)                            \
  445:         (((elm)->field.cqe_prev == (void *)(head))                      \
  446:             ? ((head)->cqh_last)                                        \
  447:             : (elm->field.cqe_prev))
  448: 
  449: #endif  /* !QEMU_SYS_QUEUE_H_ */

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