1 /*
2 * Copyright © 2011 Intel Corporation
3 * Copyright © 2016 Giulio Camuffo
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining
6 * a copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sublicense, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the
14 * next paragraph) shall be included in all copies or substantial
15 * portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
21 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
22 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
23 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
24 * SOFTWARE.
25 */
26
27 #include "config.h"
28
29 #include <signal.h>
30 #include <string.h>
31 #include <errno.h>
32 #include <sys/socket.h>
33
34 #include <libweston/libweston.h>
35 #include "compositor/weston.h"
36 #include <libweston/xwayland-api.h>
37 #include "shared/helpers.h"
38
39 struct wet_xwayland {
40 struct weston_compositor *compositor;
41 const struct weston_xwayland_api *api;
42 struct weston_xwayland *xwayland;
43 struct wl_event_source *sigusr1_source;
44 struct wl_client *client;
45 int wm_fd;
46 struct weston_process process;
47 };
48
49 static int
handle_sigusr1(int signal_number,void * data)50 handle_sigusr1(int signal_number, void *data)
51 {
52 struct wet_xwayland *wxw = data;
53
54 /* We'd be safer if we actually had the struct
55 * signalfd_siginfo from the signalfd data and could verify
56 * this came from Xwayland.*/
57 wxw->api->xserver_loaded(wxw->xwayland, wxw->client, wxw->wm_fd);
58 wl_event_source_remove(wxw->sigusr1_source);
59
60 return 1;
61 }
62
63 static pid_t
spawn_xserver(void * user_data,const char * display,int abstract_fd,int unix_fd)64 spawn_xserver(void *user_data, const char *display, int abstract_fd, int unix_fd)
65 {
66 struct wet_xwayland *wxw = user_data;
67 pid_t pid;
68 char s[12], abstract_fd_str[12], unix_fd_str[12], wm_fd_str[12];
69 int sv[2], wm[2], fd;
70 char *xserver = NULL;
71 struct weston_config *config = wet_get_config(wxw->compositor);
72 struct weston_config_section *section;
73
74 if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, sv) < 0) {
75 weston_log("wl connection socketpair failed\n");
76 return 1;
77 }
78
79 if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, wm) < 0) {
80 weston_log("X wm connection socketpair failed\n");
81 return 1;
82 }
83
84 pid = fork();
85 switch (pid) {
86 case 0:
87 /* SOCK_CLOEXEC closes both ends, so we need to unset
88 * the flag on the client fd. */
89 fd = dup(sv[1]);
90 if (fd < 0)
91 goto fail;
92 snprintf(s, sizeof s, "%d", fd);
93 setenv("WAYLAND_SOCKET", s, 1);
94
95 fd = dup(abstract_fd);
96 if (fd < 0)
97 goto fail;
98 snprintf(abstract_fd_str, sizeof abstract_fd_str, "%d", fd);
99 fd = dup(unix_fd);
100 if (fd < 0)
101 goto fail;
102 snprintf(unix_fd_str, sizeof unix_fd_str, "%d", fd);
103 fd = dup(wm[1]);
104 if (fd < 0)
105 goto fail;
106 snprintf(wm_fd_str, sizeof wm_fd_str, "%d", fd);
107
108 section = weston_config_get_section(config,
109 "xwayland", NULL, NULL);
110 weston_config_section_get_string(section, "path",
111 &xserver, XSERVER_PATH);
112
113 /* Ignore SIGUSR1 in the child, which will make the X
114 * server send SIGUSR1 to the parent (weston) when
115 * it's done with initialization. During
116 * initialization the X server will round trip and
117 * block on the wayland compositor, so avoid making
118 * blocking requests (like xcb_connect_to_fd) until
119 * it's done with that. */
120 signal(SIGUSR1, SIG_IGN);
121
122 if (execl(xserver,
123 xserver,
124 display,
125 "-rootless",
126 "-listen", abstract_fd_str,
127 "-listen", unix_fd_str,
128 "-wm", wm_fd_str,
129 "-terminate",
130 NULL) < 0)
131 weston_log("exec of '%s %s -rootless "
132 "-listen %s -listen %s -wm %s "
133 "-terminate' failed: %s\n",
134 xserver, display,
135 abstract_fd_str, unix_fd_str, wm_fd_str,
136 strerror(errno));
137 fail:
138 _exit(EXIT_FAILURE);
139
140 default:
141 close(sv[1]);
142 wxw->client = wl_client_create(wxw->compositor->wl_display, sv[0]);
143
144 close(wm[1]);
145 wxw->wm_fd = wm[0];
146
147 wxw->process.pid = pid;
148 weston_watch_process(&wxw->process);
149 break;
150
151 case -1:
152 weston_log("Failed to fork to spawn xserver process\n");
153 break;
154 }
155
156 return pid;
157 }
158
159 static void
xserver_cleanup(struct weston_process * process,int status)160 xserver_cleanup(struct weston_process *process, int status)
161 {
162 struct wet_xwayland *wxw =
163 container_of(process, struct wet_xwayland, process);
164 struct wl_event_loop *loop =
165 wl_display_get_event_loop(wxw->compositor->wl_display);
166
167 wxw->api->xserver_exited(wxw->xwayland, status);
168 wxw->sigusr1_source = wl_event_loop_add_signal(loop, SIGUSR1,
169 handle_sigusr1, wxw);
170 wxw->client = NULL;
171 }
172
173 int
wet_load_xwayland(struct weston_compositor * comp)174 wet_load_xwayland(struct weston_compositor *comp)
175 {
176 const struct weston_xwayland_api *api;
177 struct weston_xwayland *xwayland;
178 struct wet_xwayland *wxw;
179 struct wl_event_loop *loop;
180
181 if (weston_compositor_load_xwayland(comp) < 0)
182 return -1;
183
184 api = weston_xwayland_get_api(comp);
185 if (!api) {
186 weston_log("Failed to get the xwayland module API.\n");
187 return -1;
188 }
189
190 xwayland = api->get(comp);
191 if (!xwayland) {
192 weston_log("Failed to get the xwayland object.\n");
193 return -1;
194 }
195
196 wxw = zalloc(sizeof *wxw);
197 if (!wxw)
198 return -1;
199
200 wxw->compositor = comp;
201 wxw->api = api;
202 wxw->xwayland = xwayland;
203 wxw->process.cleanup = xserver_cleanup;
204 if (api->listen(xwayland, wxw, spawn_xserver) < 0)
205 return -1;
206
207 loop = wl_display_get_event_loop(comp->wl_display);
208 wxw->sigusr1_source = wl_event_loop_add_signal(loop, SIGUSR1,
209 handle_sigusr1, wxw);
210
211 return 0;
212 }
213