64 lines
1.4 KiB
C
64 lines
1.4 KiB
C
/*
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** Copyright 2002, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
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** Distributed under the terms of the MIT License.
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*/
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#ifndef KQUEUE_H
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#define KQUEUE_H
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/* The name "que" actually means that it is a very
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* light-weight implementation of a queue ;-))
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*/
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/* The object that is put into a queue must begin with these
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* fields, but it doesn't have to be this structure.
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*/
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struct quehead {
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struct quehead *next;
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struct quehead *prev;
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};
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/* You can use this macro to iterate through the queue. */
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#define kqueue_foreach(head, element) \
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for ((element) = (void *)(head)->next; (element) != (void *)(head); (element) = (void *)((struct quehead *)(element))->next)
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/** Initializes a queue to be used */
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static inline void
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initque(void *_head)
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{
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struct quehead *head = (struct quehead *)_head;
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head->next = head->prev = head;
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}
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/** Inserts an element (_element) to the queue (_head) */
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static inline void
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insque(void *_element, void *_head)
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{
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struct quehead *element = (struct quehead *)_element,
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*head = (struct quehead *)_head;
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element->next = head->next;
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element->prev = head;
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head->next = element;
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element->next->prev = element;
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}
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/** removes an element from the queue it's currently in */
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static inline void
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remque(void *_element)
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{
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struct quehead *element = (struct quehead *)_element;
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element->next->prev = element->prev;
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element->prev->next = element->next;
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element->prev = 0;
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}
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#endif /* KQUEUE_H */
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