1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 */
5
6#include <stddef.h>
7#include <stdio.h>
8#include <stdlib.h>
9#include <unistd.h>
10#include <errno.h>
11#include <string.h>
12#include <termios.h>
13#include "chan_user.h"
14#include <os.h>
15#include <um_malloc.h>
16#include "xterm.h"
17
18struct xterm_chan {
19 int pid;
20 int helper_pid;
21 int chan_fd;
22 char *title;
23 int device;
24 int raw;
25 struct termios tt;
26};
27
28static void *xterm_init(char *str, int device, const struct chan_opts *opts)
29{
30 struct xterm_chan *data;
31
32 data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
33 if (data == NULL)
34 return NULL;
35 *data = ((struct xterm_chan) { .pid = -1,
36 .helper_pid = -1,
37 .chan_fd = -1,
38 .device = device,
39 .title = opts->xterm_title,
40 .raw = opts->raw } );
41 return data;
42}
43
44/* Only changed by xterm_setup, which is a setup */
45static char *terminal_emulator = CONFIG_XTERM_CHAN_DEFAULT_EMULATOR;
46static char *title_switch = "-T";
47static char *exec_switch = "-e";
48
49static int __init xterm_setup(char *line, int *add)
50{
51 *add = 0;
52 terminal_emulator = line;
53
54 line = strchr(line, ',');
55 if (line == NULL)
56 return 0;
57
58 *line++ = '\0';
59 if (*line)
60 title_switch = line;
61
62 line = strchr(line, ',');
63 if (line == NULL)
64 return 0;
65
66 *line++ = '\0';
67 if (*line)
68 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=" CONFIG_XTERM_CHAN_DEFAULT_EMULATOR
83 ",-T,-e'.\n"
84" Values for gnome-terminal are 'xterm=gnome-terminal,-t,-x'.\n\n"
85);
86
87static int xterm_open(int input, int output, int primary, void *d,
88 char **dev_out)
89{
90 struct xterm_chan *data = d;
91 int pid, fd, new, err;
92 char title[256], file[] = "/tmp/xterm-pipeXXXXXX";
93 char *argv[] = { terminal_emulator, title_switch, title, exec_switch,
94 OS_LIB_PATH "/uml/port-helper", "-uml-socket",
95 file, NULL };
96
97 if (access(argv[4], X_OK) < 0)
98 argv[4] = "port-helper";
99
100 /*
101 * Check that DISPLAY is set, this doesn't guarantee the xterm
102 * will work but w/o it we can be pretty sure it won't.
103 */
104 if (getenv("DISPLAY") == NULL) {
105 printk(UM_KERN_ERR "xterm_open: $DISPLAY not set.\n");
106 return -ENODEV;
107 }
108
109 /*
110 * This business of getting a descriptor to a temp file,
111 * deleting the file and closing the descriptor is just to get
112 * a known-unused name for the Unix socket that we really
113 * want.
114 */
115 fd = mkstemp(file);
116 if (fd < 0) {
117 err = -errno;
118 printk(UM_KERN_ERR "xterm_open : mkstemp failed, errno = %d\n",
119 errno);
120 return err;
121 }
122
123 if (unlink(file)) {
124 err = -errno;
125 printk(UM_KERN_ERR "xterm_open : unlink failed, errno = %d\n",
126 errno);
127 close(fd);
128 return err;
129 }
130 close(fd);
131
132 fd = os_create_unix_socket(file, sizeof(file), 1);
133 if (fd < 0) {
134 printk(UM_KERN_ERR "xterm_open : create_unix_socket failed, "
135 "errno = %d\n", -fd);
136 return fd;
137 }
138
139 sprintf(title, data->title, data->device);
140 pid = run_helper(NULL, NULL, argv);
141 if (pid < 0) {
142 err = pid;
143 printk(UM_KERN_ERR "xterm_open : run_helper failed, "
144 "errno = %d\n", -err);
145 goto out_close1;
146 }
147
148 err = os_set_fd_block(fd, 0);
149 if (err < 0) {
150 printk(UM_KERN_ERR "xterm_open : failed to set descriptor "
151 "non-blocking, err = %d\n", -err);
152 goto out_kill;
153 }
154
155 data->chan_fd = fd;
156 new = xterm_fd(socket: fd, pid_out: &data->helper_pid);
157 if (new < 0) {
158 err = new;
159 printk(UM_KERN_ERR "xterm_open : os_rcv_fd failed, err = %d\n",
160 -err);
161 goto out_kill;
162 }
163
164 err = os_set_fd_block(new, 0);
165 if (err) {
166 printk(UM_KERN_ERR "xterm_open : failed to set xterm "
167 "descriptor non-blocking, err = %d\n", -err);
168 goto out_close2;
169 }
170
171 CATCH_EINTR(err = tcgetattr(new, &data->tt));
172 if (err) {
173 new = err;
174 goto out_close2;
175 }
176
177 if (data->raw) {
178 err = raw(new);
179 if (err) {
180 new = err;
181 goto out_close2;
182 }
183 }
184
185 unlink(file);
186 data->pid = pid;
187 *dev_out = NULL;
188
189 return new;
190
191 out_close2:
192 close(new);
193 out_kill:
194 os_kill_process(pid, 1);
195 out_close1:
196 close(fd);
197
198 return err;
199}
200
201static void xterm_close(int fd, void *d)
202{
203 struct xterm_chan *data = d;
204
205 if (data->pid != -1)
206 os_kill_process(data->pid, 1);
207 data->pid = -1;
208
209 if (data->helper_pid != -1)
210 os_kill_process(data->helper_pid, 0);
211 data->helper_pid = -1;
212
213 if (data->chan_fd != -1)
214 os_close_file(data->chan_fd);
215 os_close_file(fd);
216}
217
218const struct chan_ops xterm_ops = {
219 .type = "xterm",
220 .init = xterm_init,
221 .open = xterm_open,
222 .close = xterm_close,
223 .read = generic_read,
224 .write = generic_write,
225 .console_write = generic_console_write,
226 .window_size = generic_window_size,
227 .free = generic_free,
228 .winch = 1,
229};
230

source code of linux/arch/um/drivers/xterm.c