summaryrefslogtreecommitdiffstats
path: root/arch/um/drivers/slirp_user.c
blob: c322515c71ccb4071cc6b0e4cf718720d047cbba (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
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <stddef.h>
#include <sched.h>
#include <string.h>
#include <errno.h>
#include <sys/wait.h>
#include <sys/signal.h>
#include "user_util.h"
#include "kern_util.h"
#include "user.h"
#include "net_user.h"
#include "slirp.h"
#include "slip_proto.h"
#include "helper.h"
#include "os.h"

void slirp_user_init(void *data, void *dev)
{
	struct slirp_data *pri = data;

	pri->dev = dev;
}

struct slirp_pre_exec_data {
	int stdin;
	int stdout;
};

static void slirp_pre_exec(void *arg)
{
	struct slirp_pre_exec_data *data = arg;

	if(data->stdin != -1) dup2(data->stdin, 0);
	if(data->stdout != -1) dup2(data->stdout, 1);
}

static int slirp_tramp(char **argv, int fd)
{
	struct slirp_pre_exec_data pe_data;
	int pid;

	pe_data.stdin = fd;
	pe_data.stdout = fd;
	pid = run_helper(slirp_pre_exec, &pe_data, argv, NULL);

	return(pid);
}

/* XXX This is just a trivial wrapper around os_pipe */
static int slirp_datachan(int *mfd, int *sfd)
{
	int fds[2], err;

	err = os_pipe(fds, 1, 1);
	if(err < 0){
		printk("slirp_datachan: Failed to open pipe, err = %d\n", -err);
		return(err);
	}

	*mfd = fds[0];
	*sfd = fds[1];
	return(0);
}

static int slirp_open(void *data)
{
	struct slirp_data *pri = data;
	int sfd, mfd, pid, err;

	err = slirp_datachan(&mfd, &sfd);
	if(err)
		return(err);

	pid = slirp_tramp(pri->argw.argv, sfd);

	if(pid < 0){
		printk("slirp_tramp failed - errno = %d\n", -pid);
		os_close_file(sfd);	
		os_close_file(mfd);	
		return(pid);
	}

	pri->slave = sfd;
	pri->pos = 0;
	pri->esc = 0;

	pri->pid = pid;

	return(mfd);
}

static void slirp_close(int fd, void *data)
{
	struct slirp_data *pri = data;
	int status,err;

	os_close_file(fd);
	os_close_file(pri->slave);

	pri->slave = -1;

	if(pri->pid<1) {
		printk("slirp_close: no child process to shut down\n");
		return;
	}

#if 0
	if(kill(pri->pid, SIGHUP)<0) {
		printk("slirp_close: sending hangup to %d failed (%d)\n",
			pri->pid, errno);
	}
#endif

	CATCH_EINTR(err = waitpid(pri->pid, &status, WNOHANG));
	if(err < 0) {
		printk("slirp_close: waitpid returned %d\n", errno);
		return;
	}

	if(err == 0) {
		printk("slirp_close: process %d has not exited\n");
		return;
	}

	pri->pid = -1;
}

int slirp_user_read(int fd, void *buf, int len, struct slirp_data *pri)
{
	int i, n, size, start;

	if(pri->more>0) {
		i = 0;
		while(i < pri->more) {
			size = slip_unesc(pri->ibuf[i++],
					pri->ibuf,&pri->pos,&pri->esc);
			if(size){
				memcpy(buf, pri->ibuf, size);
				memmove(pri->ibuf, &pri->ibuf[i], pri->more-i);
				pri->more=pri->more-i; 
				return(size);
			}
		}
		pri->more=0;
	}

	n = net_read(fd, &pri->ibuf[pri->pos], sizeof(pri->ibuf) - pri->pos);
	if(n <= 0) return(n);

	start = pri->pos;
	for(i = 0; i < n; i++){
		size = slip_unesc(pri->ibuf[start + i],
				pri->ibuf,&pri->pos,&pri->esc);
		if(size){
			memcpy(buf, pri->ibuf, size);
			memmove(pri->ibuf, &pri->ibuf[start+i+1], n-(i+1));
			pri->more=n-(i+1); 
			return(size);
		}
	}
	return(0);
}

int slirp_user_write(int fd, void *buf, int len, struct slirp_data *pri)
{
	int actual, n;

	actual = slip_esc(buf, pri->obuf, len);
	n = net_write(fd, pri->obuf, actual);
	if(n < 0) return(n);
	else return(len);
}

static int slirp_set_mtu(int mtu, void *data)
{
	return(mtu);
}

struct net_user_info slirp_user_info = {
	.init		= slirp_user_init,
	.open		= slirp_open,
	.close	 	= slirp_close,
	.remove	 	= NULL,
	.set_mtu	= slirp_set_mtu,
	.add_address	= NULL,
	.delete_address = NULL,
	.max_packet	= BUF_SIZE
};

/*
 * 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:
 */