Ignore tty input

Previously, ctrl-c would kill wayland and input like
passwords and commands would get typed into the terminal
under the scenes.

diff --git a/wayland-system-compositor.c b/wayland-system-compositor.c
index d6a4411..fb44ab9 100644 (file)
--- a/wayland-system-compositor.c
+++ b/wayland-system-compositor.c
@@ -18,9 +18,11 @@
 
 #include <stdio.h>
 #include <string.h>
+#include <stdbool.h>
 #include <stdlib.h>
 #include <stdint.h>
 #include <stdarg.h>
+#include <termios.h>
 #include <i915_drm.h>
 #include <sys/ioctl.h>
 #include <sys/mman.h>
@@ -74,13 +76,19 @@ struct egl_compositor {
        EGLContext context;
        EGLConfig config;
        struct wl_display *wl_display;
-       int tty_fd;
        int width, height, stride;
        struct egl_surface *background;
 
        struct wl_list input_device_list;
        struct wl_list surface_list;
 
+       struct wl_event_source *term_signal_source;
+
+        /* tty handling state */
+       int tty_fd;
+
+       struct termios terminal_attributes;
+       struct wl_event_source *tty_input_source;
        struct wl_event_source *enter_vt_source;
        struct wl_event_source *leave_vt_source;
 
@@ -863,11 +871,72 @@ static void on_leave_vt(int signal_number, void *data)
        ioctl (ec->tty_fd, VT_RELDISP, 1);
 }
 
+static bool open_active_tty(struct egl_compositor *ec)
+{
+       ec->tty_fd = open("/dev/tty0", O_RDWR | O_NOCTTY);
+
+       if (ec->tty_fd <= 0) {
+               fprintf(stderr, "failed to open active tty: %m\n");
+               return FALSE;
+       }
+       return TRUE;
+}
+
+static void
+on_tty_input(int fd, uint32_t mask, void *data)
+{
+       struct egl_compositor *ec = data;
+
+       /* Ignore input to tty.  We get keyboard events from evdev
+        */
+       tcflush(ec->tty_fd, TCIFLUSH);
+}
+
+static void on_term_signal(int signal_number, void *data)
+{
+       struct egl_compositor *ec = data;
+
+       if (tcsetattr(ec->tty_fd, TCSANOW, &ec->terminal_attributes) < 0)
+               fprintf(stderr, "could not restore terminal to canonical mode\n");
+
+       exit(0);
+}
+
+static void ignore_tty_input(struct egl_compositor *ec, struct wl_event_loop *loop)
+{
+       struct termios raw_attributes;
+
+       if (tcgetattr(ec->tty_fd, &ec->terminal_attributes) < 0) {
+               fprintf(stderr, "could not get terminal attributes: %m\n");
+               return;
+       }
+
+       /* Ignore control characters and disable echo
+        */
+       raw_attributes = ec->terminal_attributes;
+       cfmakeraw (&raw_attributes);
+
+       /* Fix up line endings to be normal
+        * (cfmakeraw hoses them)
+        */
+       raw_attributes.c_oflag |= OPOST | OCRNL;
+
+       if (tcsetattr(ec->tty_fd, TCSANOW, &raw_attributes) < 0)
+               fprintf(stderr, "could not put terminal into raw mode: %m\n");
+
+       ec->term_signal_source = wl_event_loop_add_signal(loop, SIGTERM,
+                                                       on_term_signal,
+                                                       ec);
+
+       ec->tty_input_source = wl_event_loop_add_fd(loop, ec->tty_fd,
+                                                 WL_EVENT_READABLE,
+                                                 on_tty_input, ec);
+}
+
 static void watch_for_vt_changes(struct egl_compositor *ec, struct wl_event_loop *loop)
 {
        struct vt_mode mode = { 0 };
 
-       ec->tty_fd = open("/dev/tty0", O_RDWR | O_NOCTTY);
        mode.mode = VT_PROCESS;
        mode.relsig = SIGUSR1;
        mode.acqsig = SIGUSR2;
@@ -968,7 +1037,10 @@ egl_compositor_create(struct wl_display *display)
        wl_display_add_global(display, &shooter->base);
 
        loop = wl_display_get_event_loop(ec->wl_display);
-       watch_for_vt_changes (ec, loop);
+       if (open_active_tty (ec)) {
+               ignore_tty_input (ec, loop);
+               watch_for_vt_changes (ec, loop);
+       }
        ec->timer_source = wl_event_loop_add_timer(loop, repaint, ec);
        ec->repaint_needed = 0;
        ec->repaint_on_timeout = 0;