From e19dd83925b062d15422a318f727ddef6042023e Mon Sep 17 00:00:00 2001
From: Glenn Watson <gw@intuitionlibrary.com>
Date: Mon, 27 Oct 2014 14:55:36 +1000
Subject: [PATCH] Add support for keyboard modifiers on x11.

---
 src/x11/window/mod.rs | 34 +++++++++++++++++++++++++++++++---
 1 file changed, 31 insertions(+), 3 deletions(-)

diff --git a/src/x11/window/mod.rs b/src/x11/window/mod.rs
index 99cbf9dc..0a1359b6 100644
--- a/src/x11/window/mod.rs
+++ b/src/x11/window/mod.rs
@@ -1,6 +1,7 @@
-use {Event, WindowBuilder};
+use {Event, WindowBuilder, KeyModifiers};
 use libc;
 use std::{mem, ptr};
+use std::cell::Cell;
 use std::sync::atomic::AtomicBool;
 use super::ffi;
 use sync::one::{Once, ONCE_INIT};
@@ -31,6 +32,7 @@ pub struct Window {
     xf86_desk_mode: *mut ffi::XF86VidModeModeInfo,
     screen_id: libc::c_int,
     is_fullscreen: bool,
+    current_modifiers: Cell<KeyModifiers>,
 }
 
 impl Window {
@@ -255,6 +257,7 @@ impl Window {
             xf86_desk_mode: xf86_desk_mode,
             screen_id: screen_id,
             is_fullscreen: builder.monitor.is_some(),
+            current_modifiers: Cell::new(KeyModifiers::empty()),
         };
 
         // calling glViewport
@@ -375,7 +378,10 @@ impl Window {
                 },
 
                 ffi::KeyPress | ffi::KeyRelease => {
-                    use {KeyboardInput, Pressed, Released, ReceivedCharacter, KeyModifiers};
+                    use {KeyboardInput, Pressed, Released, ReceivedCharacter};
+                    use {LEFT_CONTROL_MODIFIER, RIGHT_CONTROL_MODIFIER};
+                    use {LEFT_SHIFT_MODIFIER, RIGHT_SHIFT_MODIFIER};
+                    use {LEFT_ALT_MODIFIER, RIGHT_ALT_MODIFIER, CAPS_LOCK_MODIFIER};
                     let event: &mut ffi::XKeyEvent = unsafe { mem::transmute(&xev) };
 
                     if event.type_ == ffi::KeyPress {
@@ -406,10 +412,32 @@ impl Window {
                         ffi::XKeycodeToKeysym(self.display, event.keycode as ffi::KeyCode, 0)
                     };
 
+                    let modifier_flag = match keysym as u32 {
+                        ffi::XK_Shift_L => Some(LEFT_SHIFT_MODIFIER),
+                        ffi::XK_Shift_R => Some(RIGHT_SHIFT_MODIFIER),
+                        ffi::XK_Control_L => Some(LEFT_CONTROL_MODIFIER),
+                        ffi::XK_Control_R => Some(RIGHT_CONTROL_MODIFIER),
+                        ffi::XK_Caps_Lock => Some(CAPS_LOCK_MODIFIER),
+                        ffi::XK_Meta_L => Some(LEFT_ALT_MODIFIER),
+                        ffi::XK_Meta_R => Some(RIGHT_ALT_MODIFIER),
+                        _ => None,
+                    };
+                    match modifier_flag {
+                        Some(flag) => {
+                            let mut current_modifiers = self.current_modifiers.get();
+                            match state {
+                                Pressed => current_modifiers.insert(flag),
+                                Released => current_modifiers.remove(flag),
+                            }
+                            self.current_modifiers.set(current_modifiers);
+                        }
+                        None => {}
+                    }
+
                     let vkey =  events::keycode_to_element(keysym as libc::c_uint);
 
                     events.push(KeyboardInput(state, event.keycode as u8,
-                        vkey, KeyModifiers::empty()));
+                        vkey, self.current_modifiers.get()));
                     //
                 },