xref: /linux/arch/um/drivers/xterm.c (revision 0a0fc0ddbe732779366ab6b1b879f62195e65967)
1 /*
2  * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
3  * Licensed under the GPL
4  */
5 
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <unistd.h>
9 #include <string.h>
10 #include <errno.h>
11 #include <termios.h>
12 #include <signal.h>
13 #include <sched.h>
14 #include <sys/socket.h>
15 #include "kern_util.h"
16 #include "chan_user.h"
17 #include "user_util.h"
18 #include "user.h"
19 #include "os.h"
20 #include "xterm.h"
21 
22 struct xterm_chan {
23 	int pid;
24 	int helper_pid;
25 	char *title;
26 	int device;
27 	int raw;
28 	struct termios tt;
29 	unsigned long stack;
30 	int direct_rcv;
31 };
32 
33 /* Not static because it's called directly by the tt mode gdb code */
34 void *xterm_init(char *str, int device, struct chan_opts *opts)
35 {
36 	struct xterm_chan *data;
37 
38 	data = malloc(sizeof(*data));
39 	if(data == NULL) return(NULL);
40 	*data = ((struct xterm_chan) { .pid 		= -1,
41 				       .helper_pid 	= -1,
42 				       .device 		= device,
43 				       .title 		= opts->xterm_title,
44 				       .raw  		= opts->raw,
45 				       .stack 		= opts->tramp_stack,
46 				       .direct_rcv 	= !opts->in_kernel } );
47 	return(data);
48 }
49 
50 /* Only changed by xterm_setup, which is a setup */
51 static char *terminal_emulator = "xterm";
52 static char *title_switch = "-T";
53 static char *exec_switch = "-e";
54 
55 static int __init xterm_setup(char *line, int *add)
56 {
57 	*add = 0;
58 	terminal_emulator = line;
59 
60 	line = strchr(line, ',');
61 	if(line == NULL) return(0);
62 	*line++ = '\0';
63 	if(*line) title_switch = line;
64 
65 	line = strchr(line, ',');
66 	if(line == NULL) return(0);
67 	*line++ = '\0';
68 	if(*line) exec_switch = line;
69 
70 	return(0);
71 }
72 
73 __uml_setup("xterm=", xterm_setup,
74 "xterm=<terminal emulator>,<title switch>,<exec switch>\n"
75 "    Specifies an alternate terminal emulator to use for the debugger,\n"
76 "    consoles, and serial lines when they are attached to the xterm channel.\n"
77 "    The values are the terminal emulator binary, the switch it uses to set\n"
78 "    its title, and the switch it uses to execute a subprocess,\n"
79 "    respectively.  The title switch must have the form '<switch> title',\n"
80 "    not '<switch>=title'.  Similarly, the exec switch must have the form\n"
81 "    '<switch> command arg1 arg2 ...'.\n"
82 "    The default values are 'xterm=xterm,-T,-e'.  Values for gnome-terminal\n"
83 "    are 'xterm=gnome-terminal,-t,-x'.\n\n"
84 );
85 
86 /* XXX This badly needs some cleaning up in the error paths
87  * Not static because it's called directly by the tt mode gdb code
88  */
89 int xterm_open(int input, int output, int primary, void *d,
90 		      char **dev_out)
91 {
92 	struct xterm_chan *data = d;
93 	unsigned long stack;
94 	int pid, fd, new, err;
95 	char title[256], file[] = "/tmp/xterm-pipeXXXXXX";
96 	char *argv[] = { terminal_emulator, title_switch, title, exec_switch,
97 			 "/usr/lib/uml/port-helper", "-uml-socket",
98 			 file, NULL };
99 
100 	if(os_access(argv[4], OS_ACC_X_OK) < 0)
101 		argv[4] = "port-helper";
102 
103 	/* Check that DISPLAY is set, this doesn't guarantee the xterm
104 	 * will work but w/o it we can be pretty sure it won't. */
105 	if (!getenv("DISPLAY")) {
106 		printk("xterm_open: $DISPLAY not set.\n");
107 		return -ENODEV;
108 	}
109 
110 	fd = mkstemp(file);
111 	if(fd < 0){
112 		err = -errno;
113 		printk("xterm_open : mkstemp failed, errno = %d\n", errno);
114 		return err;
115 	}
116 
117 	if(unlink(file)){
118 		err = -errno;
119 		printk("xterm_open : unlink failed, errno = %d\n", errno);
120 		return err;
121 	}
122 	os_close_file(fd);
123 
124 	fd = os_create_unix_socket(file, sizeof(file), 1);
125 	if(fd < 0){
126 		printk("xterm_open : create_unix_socket failed, errno = %d\n",
127 		       -fd);
128 		return(fd);
129 	}
130 
131 	sprintf(title, data->title, data->device);
132 	stack = data->stack;
133 	pid = run_helper(NULL, NULL, argv, &stack);
134 	if(pid < 0){
135 		printk("xterm_open : run_helper failed, errno = %d\n", -pid);
136 		return(pid);
137 	}
138 
139 	if(data->stack == 0) free_stack(stack, 0);
140 
141 	if (data->direct_rcv) {
142 		new = os_rcv_fd(fd, &data->helper_pid);
143 	} else {
144 		err = os_set_fd_block(fd, 0);
145 		if(err < 0){
146 			printk("xterm_open : failed to set descriptor "
147 			       "non-blocking, err = %d\n", -err);
148 			return(err);
149 		}
150 		new = xterm_fd(fd, &data->helper_pid);
151 	}
152 	if(new < 0){
153 		printk("xterm_open : os_rcv_fd failed, err = %d\n", -new);
154 		goto out;
155 	}
156 
157 	CATCH_EINTR(err = tcgetattr(new, &data->tt));
158 	if(err){
159 		new = err;
160 		goto out;
161 	}
162 
163 	if(data->raw){
164 		err = raw(new);
165 		if(err){
166 			new = err;
167 			goto out;
168 		}
169 	}
170 
171 	data->pid = pid;
172 	*dev_out = NULL;
173  out:
174 	unlink(file);
175 	return(new);
176 }
177 
178 /* Not static because it's called directly by the tt mode gdb code */
179 void xterm_close(int fd, void *d)
180 {
181 	struct xterm_chan *data = d;
182 
183 	if(data->pid != -1)
184 		os_kill_process(data->pid, 1);
185 	data->pid = -1;
186 	if(data->helper_pid != -1)
187 		os_kill_process(data->helper_pid, 0);
188 	data->helper_pid = -1;
189 	os_close_file(fd);
190 }
191 
192 static void xterm_free(void *d)
193 {
194 	free(d);
195 }
196 
197 struct chan_ops xterm_ops = {
198 	.type		= "xterm",
199 	.init		= xterm_init,
200 	.open		= xterm_open,
201 	.close		= xterm_close,
202 	.read		= generic_read,
203 	.write		= generic_write,
204 	.console_write	= generic_console_write,
205 	.window_size	= generic_window_size,
206 	.free		= xterm_free,
207 	.winch		= 1,
208 };
209 
210 /*
211  * Overrides for Emacs so that we follow Linus's tabbing style.
212  * Emacs will notice this stuff at the end of the file and automatically
213  * adjust the settings for this buffer only.  This must remain at the end
214  * of the file.
215  * ---------------------------------------------------------------------------
216  * Local variables:
217  * c-file-style: "linux"
218  * End:
219  */
220