summaryrefslogtreecommitdiffstats
path: root/arch/um/drivers/pty.c
blob: 1c555c38de4d0184adb129755058b71a1449553f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
/* 
 * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
 * Licensed under the GPL
 */

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <termios.h>
#include "chan_user.h"
#include "user.h"
#include "user_util.h"
#include "kern_util.h"
#include "os.h"

struct pty_chan {
	void (*announce)(char *dev_name, int dev);
	int dev;
	int raw;
	struct termios tt;
	char dev_name[sizeof("/dev/pts/0123456\0")];
};

static void *pty_chan_init(char *str, int device, struct chan_opts *opts)
{
	struct pty_chan *data;

	data = um_kmalloc(sizeof(*data));
	if(data == NULL) return(NULL);
	*data = ((struct pty_chan) { .announce  	= opts->announce, 
				     .dev  		= device,
				     .raw  		= opts->raw });
	return(data);
}

static int pts_open(int input, int output, int primary, void *d,
		    char **dev_out)
{
	struct pty_chan *data = d;
	char *dev;
	int fd, err;

	fd = get_pty();
	if(fd < 0){
		err = -errno;
		printk("open_pts : Failed to open pts\n");
		return err;
	}
	if(data->raw){
		CATCH_EINTR(err = tcgetattr(fd, &data->tt));
		if(err)
			return(err);

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

	dev = ptsname(fd);
	sprintf(data->dev_name, "%s", dev);
	*dev_out = data->dev_name;
	if (data->announce)
		(*data->announce)(dev, data->dev);
	return(fd);
}

static int getmaster(char *line)
{
	char *pty, *bank, *cp;
	int master, err;

	pty = &line[strlen("/dev/ptyp")];
	for (bank = "pqrs"; *bank; bank++) {
		line[strlen("/dev/pty")] = *bank;
		*pty = '0';
		if (os_stat_file(line, NULL) < 0)
			break;
		for (cp = "0123456789abcdef"; *cp; cp++) {
			*pty = *cp;
			master = os_open_file(line, of_rdwr(OPENFLAGS()), 0);
			if (master >= 0) {
				char *tp = &line[strlen("/dev/")];

				/* verify slave side is usable */
				*tp = 't';
				err = os_access(line, OS_ACC_RW_OK);
				*tp = 'p';
				if(err == 0) return(master);
				(void) os_close_file(master);
			}
		}
	}
	return(-1);
}

static int pty_open(int input, int output, int primary, void *d,
		    char **dev_out)
{
	struct pty_chan *data = d;
	int fd, err;
	char dev[sizeof("/dev/ptyxx\0")] = "/dev/ptyxx";

	fd = getmaster(dev);
	if(fd < 0)
		return(-errno);

	if(data->raw){
		err = raw(fd);
		if(err)
			return(err);
	}
	
	if(data->announce) (*data->announce)(dev, data->dev);

	sprintf(data->dev_name, "%s", dev);
	*dev_out = data->dev_name;
	return(fd);
}

struct chan_ops pty_ops = {
	.type		= "pty",
	.init		= pty_chan_init,
	.open		= pty_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,
};

struct chan_ops pts_ops = {
	.type		= "pts",
	.init		= pty_chan_init,
	.open		= pts_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,
};

/*
 * Overrides for Emacs so that we follow Linus's tabbing style.
 * Emacs will notice this stuff at the end of the file and automatically
 * adjust the settings for this buffer only.  This must remain at the end
 * of the file.
 * ---------------------------------------------------------------------------
 * Local variables:
 * c-file-style: "linux"
 * End:
 */
OpenPOWER on IntegriCloud