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/*

 * Copyright (C) 2005 Jakub Jermar

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * - Redistributions of source code must retain the above copyright

 *   notice, this list of conditions and the following disclaimer.

 * - Redistributions in binary form must reproduce the above copyright

 *   notice, this list of conditions and the following disclaimer in the

 *   documentation and/or other materials provided with the distribution.

 * - The name of the author may not be used to endorse or promote products

 *   derived from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR

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

 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.

 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,

 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#ifndef __CHARDEV_H__

#define __CHARDEV_H__

#include <typedefs.h>

#include <arch/types.h>

#include <synch/waitq.h>

#include <synch/spinlock.h>

#define CHARDEV_BUFLEN 512

/* Character device operations interface. */

struct chardev_operations {

    void (* suspend)(void);     /**< Suspend pushing characters. */

    void (* resume)(void);      /**< Resume pushing characters. */

};

typedef struct chardev_operations chardev_operations_t;

/** Character input device. */

struct chardev {

    waitq_t wq;

    spinlock_t lock;        /**< Protects everything below. */

    __u8 buffer[CHARDEV_BUFLEN];

    count_t counter;

    index_t index;

    chardev_operations_t *op;   /**< Implementation of chardev operations. */

};

extern void chardev_initialize(chardev_t *chardev, chardev_operations_t *op);

void chardev_push_character(chardev_t *chardev, __u8 ch);

#endif /* __CHARDEV_H__ */