diff options
Diffstat (limited to 'include/queue.h')
-rw-r--r-- | include/queue.h | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/include/queue.h b/include/queue.h new file mode 100644 index 0000000000..2c967ee4a8 --- /dev/null +++ b/include/queue.h @@ -0,0 +1,40 @@ +/* Copyright (c) 2012 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + * + * Queue data structure. + */ + +#include "common.h" + +/* Generic queue container. + * + * head: next to dequeqe + * tail: next to enqueue + * + * Empty: + * head == tail + * Full: + * ((tail + 1) % buf_bytes) == head + */ +struct queue { + int head, tail; + int buf_bytes; /* size of buffer (in byte) */ + int unit_bytes; /* size of unit (in byte) */ + uint8_t *buf; +}; + +/* Reset the queue to empty state. */ +void queue_reset(struct queue *queue); + +/* Return TRUE if the queue is empty. */ +int queue_is_empty(const struct queue *q); + +/* Return TRUE if the queue has at least one unit space. */ +int queue_has_space(const struct queue *q, int unit_count); + +/* Add multiple units into queue. */ +void queue_add_units(struct queue *q, const void *src, int unit_count); + +/* Remove one unit from the begin of the queue. */ +int queue_remove_unit(struct queue *q, void *dest); |