xref: /OK3568_Linux_fs/kernel/arch/um/drivers/fd.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
4*4882a593Smuzhiyun  */
5*4882a593Smuzhiyun 
6*4882a593Smuzhiyun #include <stdio.h>
7*4882a593Smuzhiyun #include <stdlib.h>
8*4882a593Smuzhiyun #include <unistd.h>
9*4882a593Smuzhiyun #include <errno.h>
10*4882a593Smuzhiyun #include <termios.h>
11*4882a593Smuzhiyun #include "chan_user.h"
12*4882a593Smuzhiyun #include <os.h>
13*4882a593Smuzhiyun #include <um_malloc.h>
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun struct fd_chan {
16*4882a593Smuzhiyun 	int fd;
17*4882a593Smuzhiyun 	int raw;
18*4882a593Smuzhiyun 	struct termios tt;
19*4882a593Smuzhiyun 	char str[sizeof("1234567890\0")];
20*4882a593Smuzhiyun };
21*4882a593Smuzhiyun 
fd_init(char * str,int device,const struct chan_opts * opts)22*4882a593Smuzhiyun static void *fd_init(char *str, int device, const struct chan_opts *opts)
23*4882a593Smuzhiyun {
24*4882a593Smuzhiyun 	struct fd_chan *data;
25*4882a593Smuzhiyun 	char *end;
26*4882a593Smuzhiyun 	int n;
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun 	if (*str != ':') {
29*4882a593Smuzhiyun 		printk(UM_KERN_ERR "fd_init : channel type 'fd' must specify a "
30*4882a593Smuzhiyun 		       "file descriptor\n");
31*4882a593Smuzhiyun 		return NULL;
32*4882a593Smuzhiyun 	}
33*4882a593Smuzhiyun 	str++;
34*4882a593Smuzhiyun 	n = strtoul(str, &end, 0);
35*4882a593Smuzhiyun 	if ((*end != '\0') || (end == str)) {
36*4882a593Smuzhiyun 		printk(UM_KERN_ERR "fd_init : couldn't parse file descriptor "
37*4882a593Smuzhiyun 		       "'%s'\n", str);
38*4882a593Smuzhiyun 		return NULL;
39*4882a593Smuzhiyun 	}
40*4882a593Smuzhiyun 
41*4882a593Smuzhiyun 	data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
42*4882a593Smuzhiyun 	if (data == NULL)
43*4882a593Smuzhiyun 		return NULL;
44*4882a593Smuzhiyun 
45*4882a593Smuzhiyun 	*data = ((struct fd_chan) { .fd  	= n,
46*4882a593Smuzhiyun 				    .raw  	= opts->raw });
47*4882a593Smuzhiyun 	return data;
48*4882a593Smuzhiyun }
49*4882a593Smuzhiyun 
fd_open(int input,int output,int primary,void * d,char ** dev_out)50*4882a593Smuzhiyun static int fd_open(int input, int output, int primary, void *d, char **dev_out)
51*4882a593Smuzhiyun {
52*4882a593Smuzhiyun 	struct fd_chan *data = d;
53*4882a593Smuzhiyun 	int err;
54*4882a593Smuzhiyun 
55*4882a593Smuzhiyun 	if (data->raw && isatty(data->fd)) {
56*4882a593Smuzhiyun 		CATCH_EINTR(err = tcgetattr(data->fd, &data->tt));
57*4882a593Smuzhiyun 		if (err)
58*4882a593Smuzhiyun 			return err;
59*4882a593Smuzhiyun 
60*4882a593Smuzhiyun 		err = raw(data->fd);
61*4882a593Smuzhiyun 		if (err)
62*4882a593Smuzhiyun 			return err;
63*4882a593Smuzhiyun 	}
64*4882a593Smuzhiyun 	sprintf(data->str, "%d", data->fd);
65*4882a593Smuzhiyun 	*dev_out = data->str;
66*4882a593Smuzhiyun 	return data->fd;
67*4882a593Smuzhiyun }
68*4882a593Smuzhiyun 
fd_close(int fd,void * d)69*4882a593Smuzhiyun static void fd_close(int fd, void *d)
70*4882a593Smuzhiyun {
71*4882a593Smuzhiyun 	struct fd_chan *data = d;
72*4882a593Smuzhiyun 	int err;
73*4882a593Smuzhiyun 
74*4882a593Smuzhiyun 	if (!data->raw || !isatty(fd))
75*4882a593Smuzhiyun 		return;
76*4882a593Smuzhiyun 
77*4882a593Smuzhiyun 	CATCH_EINTR(err = tcsetattr(fd, TCSAFLUSH, &data->tt));
78*4882a593Smuzhiyun 	if (err)
79*4882a593Smuzhiyun 		printk(UM_KERN_ERR "Failed to restore terminal state - "
80*4882a593Smuzhiyun 		       "errno = %d\n", -err);
81*4882a593Smuzhiyun 	data->raw = 0;
82*4882a593Smuzhiyun }
83*4882a593Smuzhiyun 
84*4882a593Smuzhiyun const struct chan_ops fd_ops = {
85*4882a593Smuzhiyun 	.type		= "fd",
86*4882a593Smuzhiyun 	.init		= fd_init,
87*4882a593Smuzhiyun 	.open		= fd_open,
88*4882a593Smuzhiyun 	.close		= fd_close,
89*4882a593Smuzhiyun 	.read		= generic_read,
90*4882a593Smuzhiyun 	.write		= generic_write,
91*4882a593Smuzhiyun 	.console_write	= generic_console_write,
92*4882a593Smuzhiyun 	.window_size	= generic_window_size,
93*4882a593Smuzhiyun 	.free		= generic_free,
94*4882a593Smuzhiyun 	.winch		= 1,
95*4882a593Smuzhiyun };
96