Xwayland: first draft, just start server for now

This commit is contained in:
Dominique Martinet 2017-08-19 17:59:31 +02:00
parent a138657598
commit 49a823d4c6
6 changed files with 344 additions and 0 deletions

17
include/wlr/xwayland.h Normal file
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@ -0,0 +1,17 @@
#ifndef _WLR_XWAYLAND_H
#define _WLR_XWAYLAND_H
struct wlr_xwayland {
pid_t pid;
int display;
int x_fd[2], wl_fd[2], wm_fd[2];
struct wl_client *client;
struct wl_display *wl_display;
time_t server_start;
};
void wlr_xwayland_finish(struct wlr_xwayland *wlr_xwayland);
bool wlr_xwayland_init(struct wlr_xwayland *wlr_xwayland,
struct wl_display *wl_display);
#endif

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@ -0,0 +1,6 @@
#ifndef XWAYLAND_INTERNALS_H
#define XWAYLAND_INTERNALS_H
void unlink_sockets(int display);
int open_display_sockets(int socks[2]);
#endif

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@ -50,6 +50,7 @@ subdir('render')
subdir('types') subdir('types')
subdir('util') subdir('util')
subdir('xcursor') subdir('xcursor')
subdir('xwayland')
wlr_deps = [ wlr_deps = [
wayland_server, wayland_server,
@ -77,6 +78,7 @@ lib_wlr = library('wlroots', files('dummy.c'),
lib_wlr_types, lib_wlr_types,
lib_wlr_util, lib_wlr_util,
lib_wlr_xcursor, lib_wlr_xcursor,
lib_wlr_xwayland,
], ],
dependencies: wlr_deps, dependencies: wlr_deps,
include_directories: wlr_inc) include_directories: wlr_inc)

5
xwayland/meson.build Normal file
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@ -0,0 +1,5 @@
lib_wlr_xwayland = static_library('wlr_xwayland', files(
'sockets.c',
'xwayland.c',
),
include_directories: wlr_inc)

144
xwayland/sockets.c Normal file
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#define _XOPEN_SOURCE 700
#include <stdlib.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <signal.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <errno.h>
#include "wlr/util/log.h"
#include "xwayland/internals.h"
static const char *lock_fmt = "/tmp/.X%d-lock";
static const char *socket_dir = "/tmp/.X11-unix";
static const char *socket_fmt = "/tmp/.X11-unix/X%d";
static int open_socket(struct sockaddr_un *addr, size_t path_size) {
int fd, rc;
socklen_t size = offsetof(struct sockaddr_un, sun_path) + path_size + 1;
fd = socket(PF_LOCAL, SOCK_STREAM | SOCK_CLOEXEC, 0);
if (fd < 0) {
wlr_log_errno(L_ERROR, "Failed to create socket %s", addr->sun_path);
return -1;
}
if (addr->sun_path[0]) {
unlink(addr->sun_path);
}
if (bind(fd, (struct sockaddr*)addr, size) < 0) {
rc = errno;
wlr_log_errno(L_ERROR, "Failed to bind socket %s", addr->sun_path);
goto cleanup;
}
if (listen(fd, 1) < 0) {
rc = errno;
wlr_log_errno(L_ERROR, "Failed to listen to socket %s", addr->sun_path);
goto cleanup;
}
return fd;
cleanup:
close(fd);
if (addr->sun_path[0]) {
unlink(addr->sun_path);
}
errno = rc;
return -1;
}
static bool open_sockets(int socks[2], int display) {
struct sockaddr_un addr = { .sun_family = AF_LOCAL };
size_t path_size;
mkdir(socket_dir, 0777);
// TODO: non-linux apparently want another format
addr.sun_path[0] = 0;
path_size = snprintf(addr.sun_path + 1, sizeof(addr.sun_path) - 1, socket_fmt, display);
socks[0] = open_socket(&addr, path_size);
if (socks[0] < 0) {
return false;
}
path_size = snprintf(addr.sun_path, sizeof(addr.sun_path), socket_fmt, display);
socks[1] = open_socket(&addr, path_size);
if (socks[1] < 0) {
close(socks[0]);
socks[0] = -1;
return false;
}
return true;
}
void unlink_sockets(int display) {
char sun_path[64];
snprintf(sun_path, sizeof(sun_path), socket_fmt, display);
unlink(sun_path);
}
int open_display_sockets(int socks[2]) {
int lock_fd, display;
char lock_name[64];
for (display = 0; display <= 32; display++) {
snprintf(lock_name, sizeof(lock_name), lock_fmt, display);
if ((lock_fd = open(lock_name, O_WRONLY | O_CREAT | O_EXCL | O_CLOEXEC, 0444)) >= 0) {
if (!open_sockets(socks, display)) {
unlink(lock_name);
close(lock_fd);
continue;
}
char pid[12];
snprintf(pid, sizeof(pid), "%10d", getpid());
if (write(lock_fd, pid, sizeof(pid) - 1) != sizeof(pid) - 1) {
unlink(lock_name);
close(lock_fd);
continue;
}
close(lock_fd);
break;
}
if ((lock_fd = open(lock_name, O_RDONLY | O_CLOEXEC)) < 0) {
continue;
}
char pid[12] = { 0 }, *end_pid;
ssize_t bytes = read(lock_fd, pid, sizeof(pid) - 1);
close(lock_fd);
if (bytes != sizeof(pid) - 1) {
continue;
}
long int read_pid;
read_pid = strtol(pid, &end_pid, 10);
if (read_pid < 0 || read_pid > INT32_MAX || end_pid != pid + sizeof(pid)) {
continue;
}
errno = 0;
if (kill((pid_t)read_pid, 0) != 0 && errno == ESRCH) {
if (unlink(lock_name) != 0) {
continue;
}
// retry
display--;
continue;
}
}
if (display > 32) {
wlr_log(L_ERROR, "No display available in the first 33");
return -1;
}
return display;
}

170
xwayland/xwayland.c Normal file
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@ -0,0 +1,170 @@
#define _XOPEN_SOURCE 700
#define _GNU_SOURCE
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/socket.h>
#include <time.h>
#include <errno.h>
#include <wayland-server.h>
#include "wlr/util/log.h"
#include "wlr/xwayland.h"
#include "xwayland/internals.h"
static void safe_close(int fd) {
if (fd >= 0) {
close(fd);
}
}
static int unset_cloexec(int fd) {
if (fcntl(fd, F_SETFD, 0) != 0) {
wlr_log_errno(L_ERROR, "fcntl() failed on fd %d", fd);
return -1;
}
return 0;
}
static void exec_xwayland(struct wlr_xwayland *wlr_xwayland) {
if (unset_cloexec(wlr_xwayland->x_fd[0]) ||
unset_cloexec(wlr_xwayland->x_fd[1]) ||
unset_cloexec(wlr_xwayland->wm_fd[1]) ||
unset_cloexec(wlr_xwayland->wl_fd[1])) {
exit(EXIT_FAILURE);
}
char *argv[11] = { 0 };
argv[0] = "Xwayland";
if (asprintf(&argv[1], ":%d", wlr_xwayland->display) < 0) {
wlr_log_errno(L_ERROR, "asprintf failed");
exit(EXIT_FAILURE);
}
argv[2] = "-rootless";
argv[3] = "-terminate";
argv[4] = "-listen";
if (asprintf(&argv[5], "%d", wlr_xwayland->x_fd[0]) < 0) {
wlr_log_errno(L_ERROR, "asprintf failed");
exit(EXIT_FAILURE);
}
argv[6] = "-listen";
if (asprintf(&argv[7], "%d", wlr_xwayland->x_fd[1]) < 0) {
wlr_log_errno(L_ERROR, "asprintf failed");
exit(EXIT_FAILURE);
}
argv[8] = "-wm";
if (asprintf(&argv[9], "%d", wlr_xwayland->wm_fd[1]) < 0) {
wlr_log_errno(L_ERROR, "asprintf failed");
exit(EXIT_FAILURE);
}
const char *xdg_runtime = getenv("XDG_RUNTIME_DIR");
if (!xdg_runtime) {
wlr_log(L_ERROR, "XDG_RUNTIME_DIR is not set");
exit(EXIT_FAILURE);
}
char *envp[3] = { 0 };
if (asprintf(&envp[0], "XDG_RUNTIME_DIR=%s", xdg_runtime) < 0 ||
asprintf(&envp[1], "WAYLAND_SOCKET=%d", wlr_xwayland->wl_fd[1]) < 0) {
wlr_log_errno(L_ERROR, "asprintf failed");
exit(EXIT_FAILURE);
}
wlr_log(L_INFO, "Xwayland :%d -rootless -terminate -listen %d -listen %d -wm %d",
wlr_xwayland->display, wlr_xwayland->x_fd[0], wlr_xwayland->x_fd[1],
wlr_xwayland->wm_fd[1]);
execvpe("Xwayland", argv, envp);
}
static void xwayland_destroy_event(struct wl_listener *listener, void *data) {
struct wl_client *client = data;
struct wlr_xwayland *wlr_xwayland = wl_container_of(client, wlr_xwayland, client);
/* don't call client destroy */
wlr_xwayland->client = NULL;
wlr_xwayland_finish(wlr_xwayland);
if (wlr_xwayland->server_start - time(NULL) > 5) {
wlr_xwayland_init(wlr_xwayland, wlr_xwayland->wl_display);
}
}
static struct wl_listener xwayland_destroy_listener = {
.notify = xwayland_destroy_event,
};
void wlr_xwayland_finish(struct wlr_xwayland *wlr_xwayland) {
if (wlr_xwayland->client) {
wl_list_remove(&xwayland_destroy_listener.link);
wl_client_destroy(wlr_xwayland->client);
}
safe_close(wlr_xwayland->x_fd[0]);
safe_close(wlr_xwayland->x_fd[1]);
safe_close(wlr_xwayland->wl_fd[0]);
safe_close(wlr_xwayland->wl_fd[1]);
safe_close(wlr_xwayland->wm_fd[0]);
safe_close(wlr_xwayland->wm_fd[1]);
unlink_sockets(wlr_xwayland->display);
unsetenv("DISPLAY");
/* kill Xwayland process? */
}
bool wlr_xwayland_init(struct wlr_xwayland *wlr_xwayland,
struct wl_display *wl_display) {
wlr_xwayland->wl_display = wl_display;
wlr_xwayland->x_fd[0] = wlr_xwayland->x_fd[1] = -1;
wlr_xwayland->wl_fd[0] = wlr_xwayland->wl_fd[1] = -1;
wlr_xwayland->wm_fd[0] = wlr_xwayland->wm_fd[1] = -1;
wlr_xwayland->display = open_display_sockets(wlr_xwayland->x_fd);
if (wlr_xwayland->display < 0) {
wlr_xwayland_finish(wlr_xwayland);
return false;
}
if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, wlr_xwayland->wl_fd) != 0 ||
socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, wlr_xwayland->wm_fd) != 0) {
wlr_log_errno(L_ERROR, "failed to create socketpair");
wlr_xwayland_finish(wlr_xwayland);
return false;
}
if ((wlr_xwayland->pid = fork()) == 0) {
exec_xwayland(wlr_xwayland);
wlr_log_errno(L_ERROR, "execvpe failed");
exit(EXIT_FAILURE);
}
if (wlr_xwayland->pid < 0) {
wlr_log_errno(L_ERROR, "fork failed");
wlr_xwayland_finish(wlr_xwayland);
return false;
}
/* close child fds */
close(wlr_xwayland->x_fd[0]);
close(wlr_xwayland->x_fd[1]);
close(wlr_xwayland->wl_fd[1]);
close(wlr_xwayland->wm_fd[1]);
wlr_xwayland->x_fd[0] = wlr_xwayland->x_fd[1] = -1;
wlr_xwayland->wl_fd[1] = wlr_xwayland->wm_fd[1] = -1;
char display_name[16];
snprintf(display_name, sizeof(display_name), ":%d", wlr_xwayland->display);
setenv("DISPLAY", display_name, true);
wlr_xwayland->server_start = time(NULL);
if (!(wlr_xwayland->client = wl_client_create(wl_display, wlr_xwayland->wl_fd[0]))) {
wlr_log_errno(L_ERROR, "wl_client_create failed");
wlr_xwayland_finish(wlr_xwayland);
}
wl_client_add_destroy_listener(wlr_xwayland->client, &xwayland_destroy_listener);
return true;
}