diff options
Diffstat (limited to 'backend/session/direct.c')
-rw-r--r-- | backend/session/direct.c | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/backend/session/direct.c b/backend/session/direct.c new file mode 100644 index 00000000..82aa8e00 --- /dev/null +++ b/backend/session/direct.c @@ -0,0 +1,244 @@ +#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_finish(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_start(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_start(&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 = { + .start = direct_session_start, + .finish = direct_session_finish, + .open = direct_session_open, + .close = direct_session_close, + .change_vt = direct_change_vt, +}; |