memory/mozjemalloc/linkedlist.h

   1 /* -*- Mode: C; tab-width: 8; c-basic-offset: 8; indent-tabs-mode: t -*- */
   2 /* vim:set softtabstop=8 shiftwidth=8 noet: */
   3 /*-
   4  * Copyright (C) the Mozilla Foundation.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice(s), this list of conditions and the following disclaimer as
  12  *    the first lines of this file unmodified other than the possible
  13  *    addition of one or more copyright notices.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice(s), this list of conditions and the following disclaimer in
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  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
  20  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
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  29  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  *
  31  *******************************************************************************/
  32
  33 #ifndef linkedlist_h__
  34 #define linkedlist_h__
  35
  36 #include <stddef.h>
  37
  38 typedef struct LinkedList_s LinkedList;
  39
  40 struct LinkedList_s {
  41         LinkedList *next;
  42         LinkedList *prev;
  43 };
  44
  45 /* Convert from LinkedList* to foo*. */
  46 #define LinkedList_Get(e, type, prop) \
  47   (type*)((char*)(e) - offsetof(type, prop))
  48
  49 /* Insert |e| at the beginning of |l|.  */
  50 void LinkedList_InsertHead(LinkedList *l, LinkedList *e)
  51 {
  52         e->next = l;
  53         e->prev = l->prev;
  54         e->next->prev = e;
  55         e->prev->next = e;
  56 }
  57
  58 void LinkedList_Remove(LinkedList *e)
  59 {
  60         e->prev->next = e->next;
  61         e->next->prev = e->prev;
  62         e->next = e;
  63         e->prev = e;
  64 }
  65
  66 bool LinkedList_IsEmpty(LinkedList *e)
  67 {
  68         return e->next == e;
  69 }
  70
  71 void LinkedList_Init(LinkedList *e)
  72 {
  73         e->next = e;
  74         e->prev = e;
  75 }
  76
  77 #endif