Colony

/**

 * Copyright (c) 2007 Colony Project

 * 

 * Permission is hereby granted, free of charge, to any person

 * obtaining a copy of this software and associated documentation

 * files (the "Software"), to deal in the Software without

 * restriction, including without limitation the rights to use,

 * copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following

 * conditions:

 * 

 * The above copyright notice and this permission notice shall be

 * included in all copies or substantial portions of the Software.

 * 

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES

 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT

 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,

 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

 * OTHER DEALINGS IN THE SOFTWARE.

 **/

/**

 * @file queue.h

 * @brief A queue implementation

 * 

 * Implements a queue, a first in, first out data structure.

 *

 * @author Brian Coltin, Colony Project, CMU Robotics Club

 **/

#ifndef WIRELESS_QUEUE_H

#define WIRELESS_QUEUE_H

#ifndef ROBOT

#include <pthread.h>

#endif

struct node_def;

/**

 * @defgroup queue Queue

 * @brief A queue implementation

 * 

 * A queue implementation.

 *

 * @{

 **/

/**

 * @struct Queue

 * Represents a queue, a first in, first out data structure.

 **/

typedef struct

{

        /**

         * The head of the queue, the next item to be removed.

         **/

        struct node_def* head;

        /**

         * The tail of the queue, the last item added.

         **/

        struct node_def* tail;

        /**

         * The number of elements in the queue.

         **/

        int size;

#ifndef ROBOT

        pthread_mutex_t lock;

#endif

} Queue;

/** @brief Create a new queue **/

Queue* queue_create(void);

/** @brief Destroy a queue **/

void queue_destroy(Queue* q);

/** @brief Add an element to a queue **/

int queue_add(Queue* q, void* item);

/** @brief Remove an element from a queue **/

void* queue_remove(Queue* q);

/** @brief Remove all instances of a given element from a queue **/

void queue_remove_all(Queue* q, void* item);

/** @brief Get the size of a queue **/

int queue_size(Queue* q);

/** @brief Check if the queue is empty **/

int queue_is_empty(Queue* q);

/** @} **/

#endif