1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
4 */
5
6#include <errno.h>
7#include <fcntl.h>
8#include <termios.h>
9#include "chan_user.h"
10#include <os.h>
11#include <um_malloc.h>
12
13struct tty_chan {
14 char *dev;
15 int raw;
16 struct termios tt;
17};
18
19static void *tty_chan_init(char *str, int device, const struct chan_opts *opts)
20{
21 struct tty_chan *data;
22
23 if (*str != ':') {
24 printk(UM_KERN_ERR "tty_init : channel type 'tty' must specify "
25 "a device\n");
26 return NULL;
27 }
28 str++;
29
30 data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
31 if (data == NULL)
32 return NULL;
33 *data = ((struct tty_chan) { .dev = str,
34 .raw = opts->raw });
35
36 return data;
37}
38
39static int tty_open(int input, int output, int primary, void *d,
40 char **dev_out)
41{
42 struct tty_chan *data = d;
43 int fd, err, mode = 0;
44
45 if (input && output)
46 mode = O_RDWR;
47 else if (input)
48 mode = O_RDONLY;
49 else if (output)
50 mode = O_WRONLY;
51
52 fd = open(data->dev, mode);
53 if (fd < 0)
54 return -errno;
55
56 if (data->raw) {
57 CATCH_EINTR(err = tcgetattr(fd, &data->tt));
58 if (err)
59 return err;
60
61 err = raw(fd);
62 if (err)
63 return err;
64 }
65
66 *dev_out = data->dev;
67 return fd;
68}
69
70const struct chan_ops tty_ops = {
71 .type = "tty",
72 .init = tty_chan_init,
73 .open = tty_open,
74 .close = generic_close,
75 .read = generic_read,
76 .write = generic_write,
77 .console_write = generic_console_write,
78 .window_size = generic_window_size,
79 .free = generic_free,
80 .winch = 0,
81};
82

source code of linux/arch/um/drivers/tty.c