wlroots/backend/session/direct.c

245 lines
5.7 KiB
C

#define _POSIX_C_SOURCE 200809L
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdbool.h>
#include <unistd.h>
#include <signal.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/sysmacros.h>
#include <linux/kd.h>
#include <linux/major.h>
#include <linux/input.h>
#include <linux/vt.h>
#include <wayland-server.h>
#include <wlr/backend/session/interface.h>
#include <wlr/util/log.h>
#include "backend/session/direct-ipc.h"
enum { DRM_MAJOR = 226 };
const struct session_impl session_direct;
struct direct_session {
struct wlr_session base;
int tty_fd;
int old_kbmode;
int sock;
pid_t child;
struct wl_event_source *vt_source;
};
static int direct_session_open(struct wlr_session *base, const char *path) {
struct direct_session *session = wl_container_of(base, session, base);
int fd = direct_ipc_open(session->sock, path);
if (fd < 0) {
wlr_log(L_ERROR, "Failed to open %s: %s%s", path, strerror(-fd),
fd == -EINVAL ? "; is another display server running?" : "");
return fd;
}
struct stat st;
if (fstat(fd, &st) < 0) {
close(fd);
return -errno;
}
if (major(st.st_rdev) == DRM_MAJOR) {
session->base.drm_fd = fd;
}
return fd;
}
static void direct_session_close(struct wlr_session *base, int fd) {
struct direct_session *session = wl_container_of(base, session, base);
struct stat st;
if (fstat(fd, &st) < 0) {
wlr_log_errno(L_ERROR, "Stat failed");
close(fd);
return;
}
if (major(st.st_rdev) == DRM_MAJOR) {
direct_ipc_dropmaster(session->sock, session->base.drm_fd);
session->base.drm_fd = -1;
} else if (major(st.st_rdev) == INPUT_MAJOR) {
ioctl(fd, EVIOCREVOKE, 0);
}
close(fd);
}
static bool direct_change_vt(struct wlr_session *base, unsigned vt) {
struct direct_session *session = wl_container_of(base, session, base);
return ioctl(session->tty_fd, VT_ACTIVATE, (int)vt) == 0;
}
static void direct_session_destroy(struct wlr_session *base) {
struct direct_session *session = wl_container_of(base, session, base);
struct vt_mode mode = {
.mode = VT_AUTO,
};
errno = 0;
ioctl(session->tty_fd, KDSKBMODE, session->old_kbmode);
ioctl(session->tty_fd, KDSETMODE, KD_TEXT);
ioctl(session->tty_fd, VT_SETMODE, &mode);
if (errno) {
wlr_log(L_ERROR, "Failed to restore tty");
}
direct_ipc_finish(session->sock, session->child);
close(session->sock);
wl_event_source_remove(session->vt_source);
close(session->tty_fd);
free(session);
}
static int vt_handler(int signo, void *data) {
struct direct_session *session = data;
if (session->base.active) {
session->base.active = false;
wl_signal_emit(&session->base.session_signal, session);
direct_ipc_dropmaster(session->sock, session->base.drm_fd);
ioctl(session->tty_fd, VT_RELDISP, 1);
} else {
ioctl(session->tty_fd, VT_RELDISP, VT_ACKACQ);
direct_ipc_setmaster(session->sock, session->base.drm_fd);
session->base.active = true;
wl_signal_emit(&session->base.session_signal, session);
}
return 1;
}
static bool setup_tty(struct direct_session *session, struct wl_display *display) {
int fd = dup(STDIN_FILENO);
if (fd == -1) {
wlr_log_errno(L_ERROR, "Cannot open tty");
return false;
}
struct stat st;
if (fstat(fd, &st) == -1 || major(st.st_rdev) != TTY_MAJOR || minor(st.st_rdev) == 0) {
wlr_log(L_ERROR, "Not running from a virtual terminal");
goto error;
}
int tty = minor(st.st_rdev);
int ret, kd_mode, old_kbmode;
ret = ioctl(fd, KDGETMODE, &kd_mode);
if (ret) {
wlr_log_errno(L_ERROR, "Failed to get tty mode");
goto error;
}
if (kd_mode != KD_TEXT) {
wlr_log(L_ERROR,
"tty already in graphics mode; is another display server running?");
goto error;
}
ioctl(fd, VT_ACTIVATE, tty);
ioctl(fd, VT_WAITACTIVE, tty);
if (ioctl(fd, KDGKBMODE, &old_kbmode)) {
wlr_log_errno(L_ERROR, "Failed to read keyboard mode");
goto error;
}
if (ioctl(fd, KDSKBMODE, K_OFF)) {
wlr_log_errno(L_ERROR, "Failed to set keyboard mode");
goto error;
}
if (ioctl(fd, KDSETMODE, KD_GRAPHICS)) {
wlr_log_errno(L_ERROR, "Failed to set graphics mode on tty");
goto error;
}
struct vt_mode mode = {
.mode = VT_PROCESS,
.relsig = SIGUSR1,
.acqsig = SIGUSR1,
};
if (ioctl(fd, VT_SETMODE, &mode) < 0) {
wlr_log(L_ERROR, "Failed to take control of tty");
goto error;
}
struct wl_event_loop *loop = wl_display_get_event_loop(display);
session->vt_source = wl_event_loop_add_signal(loop, SIGUSR1,
vt_handler, session);
if (!session->vt_source) {
goto error;
}
session->base.vtnr = tty;
session->tty_fd = fd;
session->old_kbmode = old_kbmode;
return true;
error:
close(fd);
return false;
}
static struct wlr_session *direct_session_create(struct wl_display *disp) {
struct direct_session *session = calloc(1, sizeof(*session));
if (!session) {
wlr_log_errno(L_ERROR, "Allocation failed");
return NULL;
}
session->sock = direct_ipc_init(&session->child);
if (session->sock == -1) {
goto error_session;
}
if (!setup_tty(session, disp)) {
goto error_ipc;
}
// XXX: Is it okay to trust the environment like this?
const char *seat = getenv("XDG_SEAT");
if (!seat) {
seat = "seat0";
}
wlr_log(L_INFO, "Successfully loaded direct session");
snprintf(session->base.seat, sizeof(session->base.seat), "%s", seat);
session->base.drm_fd = -1;
session->base.impl = &session_direct;
session->base.active = true;
wl_signal_init(&session->base.session_signal);
return &session->base;
error_ipc:
direct_ipc_finish(session->sock, session->child);
close(session->sock);
error_session:
free(session);
return NULL;
}
const struct session_impl session_direct = {
.create = direct_session_create,
.destroy = direct_session_destroy,
.open = direct_session_open,
.close = direct_session_close,
.change_vt = direct_change_vt,
};