tty.c

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/*
 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
 * Licensed under the GPL
 */

#include <errno.h>
#include <fcntl.h>
#include <termios.h>
#include "chan_user.h"
#include <os.h>
#include <um_malloc.h>

struct tty_chan {
    char *dev;
    int raw;
    struct termios tt;
};

static void *tty_chan_init(char *str, int device, const struct chan_opts *opts)
{
    struct tty_chan *data;

    if (*str != ':') {
        printk(UM_KERN_ERR "tty_init : channel type 'tty' must specify "
               "a device\n");
        return NULL;
    }
    str++;

    data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
    if (data == NULL)
        return NULL;
    *data = ((struct tty_chan) { .dev   = str,
                     .raw   = opts->raw });

    return data;
}

static int tty_open(int input, int output, int primary, void *d,
            char **dev_out)
{
    struct tty_chan *data = d;
    int fd, err, mode = 0;

    if (input && output)
        mode = O_RDWR;
    else if (input)
        mode = O_RDONLY;
    else if (output)
        mode = O_WRONLY;

    fd = open(data->dev, mode);
    if (fd < 0)
        return -errno;

    if (data->raw) {
        CATCH_EINTR(err = tcgetattr(fd, &data->tt));
        if (err)
            return err;

        err = raw(fd);
        if (err)
            return err;
    }

    *dev_out = data->dev;
    return fd;
}

const struct chan_ops tty_ops = {
    .type       = "tty",
    .init       = tty_chan_init,
    .open       = tty_open,
    .close      = generic_close,
    .read       = generic_read,
    .write      = generic_write,
    .console_write  = generic_console_write,
    .window_size    = generic_window_size,
    .free       = generic_free,
    .winch      = 0,
};