xref: /openbmc/linux/arch/um/drivers/slirp_user.c (revision c21b37f6)
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <unistd.h>
4 #include <stddef.h>
5 #include <sched.h>
6 #include <string.h>
7 #include <errno.h>
8 #include <sys/wait.h>
9 #include <sys/signal.h>
10 #include "kern_util.h"
11 #include "user.h"
12 #include "net_user.h"
13 #include "slirp.h"
14 #include "slip_common.h"
15 #include "os.h"
16 
17 static int slirp_user_init(void *data, void *dev)
18 {
19 	struct slirp_data *pri = data;
20 
21 	pri->dev = dev;
22 	return 0;
23 }
24 
25 struct slirp_pre_exec_data {
26 	int stdin;
27 	int stdout;
28 };
29 
30 static void slirp_pre_exec(void *arg)
31 {
32 	struct slirp_pre_exec_data *data = arg;
33 
34 	if(data->stdin != -1) dup2(data->stdin, 0);
35 	if(data->stdout != -1) dup2(data->stdout, 1);
36 }
37 
38 static int slirp_tramp(char **argv, int fd)
39 {
40 	struct slirp_pre_exec_data pe_data;
41 	int pid;
42 
43 	pe_data.stdin = fd;
44 	pe_data.stdout = fd;
45 	pid = run_helper(slirp_pre_exec, &pe_data, argv);
46 
47 	return(pid);
48 }
49 
50 static int slirp_open(void *data)
51 {
52 	struct slirp_data *pri = data;
53 	int fds[2], pid, err;
54 
55 	err = os_pipe(fds, 1, 1);
56 	if(err)
57 		return(err);
58 
59 	err = slirp_tramp(pri->argw.argv, fds[1]);
60 	if(err < 0){
61 		printk("slirp_tramp failed - errno = %d\n", -err);
62 		goto out;
63 	}
64 	pid = err;
65 
66 	pri->slave = fds[1];
67 	pri->slip.pos = 0;
68 	pri->slip.esc = 0;
69 	pri->pid = err;
70 
71 	return(fds[0]);
72 out:
73 	os_close_file(fds[0]);
74 	os_close_file(fds[1]);
75 	return err;
76 }
77 
78 static void slirp_close(int fd, void *data)
79 {
80 	struct slirp_data *pri = data;
81 	int status,err;
82 
83 	os_close_file(fd);
84 	os_close_file(pri->slave);
85 
86 	pri->slave = -1;
87 
88 	if(pri->pid<1) {
89 		printk("slirp_close: no child process to shut down\n");
90 		return;
91 	}
92 
93 #if 0
94 	if(kill(pri->pid, SIGHUP)<0) {
95 		printk("slirp_close: sending hangup to %d failed (%d)\n",
96 			pri->pid, errno);
97 	}
98 #endif
99 
100 	CATCH_EINTR(err = waitpid(pri->pid, &status, WNOHANG));
101 	if(err < 0) {
102 		printk("slirp_close: waitpid returned %d\n", errno);
103 		return;
104 	}
105 
106 	if(err == 0) {
107 		printk("slirp_close: process %d has not exited\n", pri->pid);
108 		return;
109 	}
110 
111 	pri->pid = -1;
112 }
113 
114 int slirp_user_read(int fd, void *buf, int len, struct slirp_data *pri)
115 {
116 	return slip_proto_read(fd, buf, len, &pri->slip);
117 }
118 
119 int slirp_user_write(int fd, void *buf, int len, struct slirp_data *pri)
120 {
121 	return slip_proto_write(fd, buf, len, &pri->slip);
122 }
123 
124 static int slirp_set_mtu(int mtu, void *data)
125 {
126 	return(mtu);
127 }
128 
129 const struct net_user_info slirp_user_info = {
130 	.init		= slirp_user_init,
131 	.open		= slirp_open,
132 	.close	 	= slirp_close,
133 	.remove	 	= NULL,
134 	.set_mtu	= slirp_set_mtu,
135 	.add_address	= NULL,
136 	.delete_address = NULL,
137 	.max_packet	= BUF_SIZE
138 };
139