/*
* Copyright (c) 2003 Josef Cejka
* 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/console.h>
#include <console/chardev.h>
#include <synch/waitq.h>
#include <synch/spinlock.h>
#include <arch/types.h>
#include <arch.h>
#include <func.h>
#include <print.h>
#include <atomic.h>
#define KLOG_SIZE 4096
/**< Kernel log cyclic buffer */
static char klog[KLOG_SIZE];
/**< First kernel log characters */
static index_t klog_start = 0;
/**< Number of valid kernel log characters */
static size_t klog_len = 0;
/**< Number of stored (not printed) kernel log characters */
static size_t klog_stored = 0;
static chardev_operations_t null_stdout_ops = {
.suspend = NULL,
.resume = NULL,
.write = NULL,
.read = NULL
};
chardev_t null_stdout = {
.name = "null",
.op = &null_stdout_ops
};
/** Standard input character device. */
chardev_t *stdin = NULL;
chardev_t *stdout = &null_stdout;
/** Get character from character device. Do not echo character.
*
* @param chardev Character device.
*
* @return Character read.
*/
uint8_t _getc(chardev_t *chardev)
{
uint8_t ch;
ipl_t ipl;
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 (chardev->op->read)
return chardev->op->read(chardev);
/* no other way of interacting with user, halt */
if (CPU)
else
printf("halted - no kconsole\n");
cpu_halt();
}
waitq_sleep(&chardev->wq);
ipl = interrupts_disable();
spinlock_lock(&chardev->lock);
ch = chardev->buffer[(chardev->index - chardev->counter) % CHARDEV_BUFLEN];
chardev->counter--;
spinlock_unlock(&chardev->lock);
interrupts_restore(ipl);
chardev->op->resume(chardev);
return ch;
}
/** Get string from character device.
*
* Read characters from character device until first occurrence
* of newline character.
*
* @param chardev Character device.
* @param buf Buffer where to store string terminated by '\0'.
* @param buflen Size of the buffer.
*
* @return Number of characters read.
*/
count_t
gets(chardev_t
*chardev
, char *buf
, size_t buflen
)
{
index_t index = 0;
char ch;
while (index < buflen) {
ch = _getc(chardev);
if (ch == '\b') {
if (index > 0) {
index--;
/* Space backspace, space */
}
continue;
}
if (ch == '\n') { /* end of string => write 0, return */
buf[index] = '\0';
return (count_t) index;
}
buf[index++] = ch;
}
return (count_t) index;
}
/** Get character from device & echo it to screen */
uint8_t getc(chardev_t
*chardev
)
{
uint8_t ch;
ch = _getc(chardev);
return ch;
}
{
if ((klog_stored > 0) && (stdout->op->write)) {
/* Print charaters stored in kernel log */
index_t i;
for (i = klog_len - klog_stored; i < klog_len; i++)
stdout->op->write(stdout, klog[(klog_start + i) % KLOG_SIZE]);
klog_stored = 0;
}
/* Store character in the cyclic kernel log */
klog[(klog_start + klog_len) % KLOG_SIZE] = c;
if (klog_len < KLOG_SIZE)
klog_len++;
else
klog_start = (klog_start + 1) % KLOG_SIZE;
if (stdout->op->write)
stdout->op->write(stdout, c);
else {
/* The character is just in the kernel log */
if (klog_stored < klog_len)
klog_stored++;
}
}
/** @}
*/