PageRenderTime 19ms CodeModel.GetById 12ms app.highlight 4ms RepoModel.GetById 1ms app.codeStats 0ms

/arch/um/drivers/fd.c

http://github.com/mirrors/linux
C | 95 lines | 78 code | 13 blank | 4 comment | 15 complexity | d3f949c8c1f9c1568055b47e41cdada2 MD5 | raw file
 1// SPDX-License-Identifier: GPL-2.0
 2/*
 3 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
 4 */
 5
 6#include <stdio.h>
 7#include <stdlib.h>
 8#include <unistd.h>
 9#include <errno.h>
10#include <termios.h>
11#include "chan_user.h"
12#include <os.h>
13#include <um_malloc.h>
14
15struct fd_chan {
16	int fd;
17	int raw;
18	struct termios tt;
19	char str[sizeof("1234567890\0")];
20};
21
22static void *fd_init(char *str, int device, const struct chan_opts *opts)
23{
24	struct fd_chan *data;
25	char *end;
26	int n;
27
28	if (*str != ':') {
29		printk(UM_KERN_ERR "fd_init : channel type 'fd' must specify a "
30		       "file descriptor\n");
31		return NULL;
32	}
33	str++;
34	n = strtoul(str, &end, 0);
35	if ((*end != '\0') || (end == str)) {
36		printk(UM_KERN_ERR "fd_init : couldn't parse file descriptor "
37		       "'%s'\n", str);
38		return NULL;
39	}
40
41	data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
42	if (data == NULL)
43		return NULL;
44
45	*data = ((struct fd_chan) { .fd  	= n,
46				    .raw  	= opts->raw });
47	return data;
48}
49
50static int fd_open(int input, int output, int primary, void *d, char **dev_out)
51{
52	struct fd_chan *data = d;
53	int err;
54
55	if (data->raw && isatty(data->fd)) {
56		CATCH_EINTR(err = tcgetattr(data->fd, &data->tt));
57		if (err)
58			return err;
59
60		err = raw(data->fd);
61		if (err)
62			return err;
63	}
64	sprintf(data->str, "%d", data->fd);
65	*dev_out = data->str;
66	return data->fd;
67}
68
69static void fd_close(int fd, void *d)
70{
71	struct fd_chan *data = d;
72	int err;
73
74	if (!data->raw || !isatty(fd))
75		return;
76
77	CATCH_EINTR(err = tcsetattr(fd, TCSAFLUSH, &data->tt));
78	if (err)
79		printk(UM_KERN_ERR "Failed to restore terminal state - "
80		       "errno = %d\n", -err);
81	data->raw = 0;
82}
83
84const struct chan_ops fd_ops = {
85	.type		= "fd",
86	.init		= fd_init,
87	.open		= fd_open,
88	.close		= fd_close,
89	.read		= generic_read,
90	.write		= generic_write,
91	.console_write	= generic_console_write,
92	.window_size	= generic_window_size,
93	.free		= generic_free,
94	.winch		= 1,
95};