terminal: add evdev elements to idev

The evdev-element provides linux evdev interfaces as idev-elements. This
way, all real input hardware devices on linux can be used with the idev
interface.

We use libevdev to interface with the kernel. It's a simple wrapper
library around the kernel evdev API that takes care to resync devices
after kernel-queue overflows, which is a rather non-trivial task.
Furthermore, it's a well tested interface used by all other major input
users (Xorg, weston, libinput, ...).
Last but not least, it provides nice keycode to keyname lookup tables (and
vice versa), which is really nice for debugging input problems.

1 files changed, 20 insertions, 0 deletions

diff --git a/src/libsystemd-terminal/idev.h b/src/libsystemd-terminal/idev.h
index 6f618f37af..c98fb1bfb0 100644
--- a/src/libsystemd-terminal/idev.h
+++ b/src/libsystemd-terminal/idev.h
@@ -26,6 +26,8 @@
 #pragma once
 
 #include <inttypes.h>
+#include <libudev.h>
+#include <linux/input.h>
 #include <stdbool.h>
 #include <stdlib.h>
 #include <systemd/sd-bus.h>
@@ -33,6 +35,7 @@
 #include "util.h"
 
 typedef struct idev_data                idev_data;
+typedef struct idev_data_evdev          idev_data_evdev;
 
 typedef struct idev_event               idev_event;
 typedef struct idev_device              idev_device;
@@ -44,6 +47,7 @@ typedef struct idev_context             idev_context;
  */
 
 enum {
+        IDEV_ELEMENT_EVDEV,
         IDEV_ELEMENT_CNT
 };
 
@@ -52,17 +56,30 @@ enum {
 };
 
 /*
+ * Evdev Elements
+ */
+
+struct idev_data_evdev {
+        struct input_event event;
+};
+
+/*
  * Data Packets
  */
 
 enum {
         IDEV_DATA_RESYNC,
+        IDEV_DATA_EVDEV,
         IDEV_DATA_CNT
 };
 
 struct idev_data {
         unsigned int type;
         bool resync : 1;
+
+        union {
+                idev_data_evdev evdev;
+        };
 };
 
 /*
@@ -122,6 +139,9 @@ bool idev_session_is_enabled(idev_session *s);
 void idev_session_enable(idev_session *s);
 void idev_session_disable(idev_session *s);
 
+int idev_session_add_evdev(idev_session *s, struct udev_device *ud);
+int idev_session_remove_evdev(idev_session *s, struct udev_device *ud);
+
 /*
  * Contexts
  */