/*
* 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.
*/
/** @addtogroup genericconsole
* @{
*/
/** @file
*/
#include <console/chardev.h>
#include <synch/waitq.h>
#include <synch/spinlock.h>
#include <print.h>
#include <func.h>
#include <arch.h>
/** Initialize input character device.
*
* @param indev Input character device.
* @param op Implementation of input character device operations.
*
*/
void indev_initialize(char *name, indev_t *indev,
indev_operations_t *op)
{
indev->name = name;
waitq_initialize(&indev->wq);
spinlock_initialize(&indev->lock, "indev");
indev->counter = 0;
indev->index = 0;
indev->op = op;
}
/** Push character read from input character device.
*
* @param indev Input character device.
* @param ch Character being pushed.
*
*/
void indev_push_character(indev_t *indev, wchar_t ch)
{
ASSERT(indev);
spinlock_lock(&indev->lock);
if (indev->counter == INDEV_BUFLEN - 1) {
/* Buffer full */
spinlock_unlock(&indev->lock);
return;
}
indev->counter++;
indev->buffer[indev->index++] = ch;
/* Index modulo size of buffer */
indev->index = indev->index % INDEV_BUFLEN;
waitq_wakeup(&indev->wq, WAKEUP_FIRST);
spinlock_unlock(&indev->lock);
}
/** Pop character from input character device.
*
* @param indev Input character device.
*
* @return Character read.
*
*/
wchar_t indev_pop_character(indev_t *indev)
{
if (atomic_get(&haltstate)) {
/* If we are here, we are hopefully on the processor that
* issued the 'halt' command, so proceed to read the character
* directly from input
*/
if (check_poll(indev))
return indev->op->poll(indev);
/* No other way of interacting with user */
interrupts_disable();
if (CPU)
else
printf("halted (no polling input)\n");
cpu_halt();
}
waitq_sleep(&indev->wq);
ipl_t ipl = interrupts_disable();
spinlock_lock(&indev->lock);
wchar_t ch = indev->buffer[(indev->index - indev->counter) % INDEV_BUFLEN];
indev->counter--;
spinlock_unlock(&indev->lock);
interrupts_restore(ipl);
return ch;
}
/** Initialize output character device.
*
* @param outdev Output character device.
* @param op Implementation of output character device operations.
*
*/
void outdev_initialize(char *name, outdev_t *outdev,
outdev_operations_t *op)
{
outdev->name = name;
spinlock_initialize(&outdev->lock, "outdev");
outdev->op = op;
}
bool check_poll(indev_t *indev)
{
if (indev == NULL)
return false;
if (indev->op == NULL)
return false;
return (indev->op->poll != NULL);
}
/** @}
*/