From 15ae4416f542279c515b380289e5fd6884230974 Mon Sep 17 00:00:00 2001
From: Joel Beckmeyer <joel@beckmeyer.us>
Date: Mon, 31 Aug 2026 08:42:33 -0400
Subject: [PATCH] add Undo/Cut/Copy/Paste keycodes for Linux

---
 src/platform/linux/uhid_backend.cpp | 13 +++++++++++--
 tests/unit/test_linux_backend.cpp   |  9 +++++++++
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/src/platform/linux/uhid_backend.cpp b/src/platform/linux/uhid_backend.cpp
index eaffb3e..b32df9f 100644
--- a/src/platform/linux/uhid_backend.cpp
+++ b/src/platform/linux/uhid_backend.cpp
@@ -53,6 +53,7 @@
 #if defined(LIBVIRTUALHID_HAVE_XTEST)
   #include <X11/extensions/XTest.h>
   #include <X11/keysym.h>
+  #include <X11/XF86keysym.h>
   #include <X11/Xlib.h>
   #include <X11/Xutil.h>
 #endif
@@ -536,7 +537,7 @@ namespace lvh::detail {
     }
 
     int key_code_to_linux(KeyboardKeyCode key_code) {
-      static constexpr std::array<std::pair<KeyboardKeyCode, int>, 47> special_keys {{
+      static constexpr std::array<std::pair<KeyboardKeyCode, int>, 51> special_keys {{
         {0x08, KEY_BACKSPACE},
         {0x09, KEY_TAB},
         {0x0D, KEY_ENTER},
@@ -584,6 +585,10 @@ namespace lvh::detail {
         {0xDD, KEY_RIGHTBRACE},
         {0xDE, KEY_APOSTROPHE},
         {0xE2, KEY_102ND},
+        {0x0100, KEY_UNDO},
+        {0x0101, KEY_CUT},
+        {0x0102, KEY_COPY},
+        {0x0103, KEY_PASTE},
       }};
 
       if (const auto linux_key = mapped_keyboard_code(key_code, special_keys); linux_key.has_value()) {
@@ -2035,7 +2040,7 @@ namespace lvh::detail {
 
 #if defined(LIBVIRTUALHID_HAVE_XTEST)
     KeySym key_code_to_keysym(KeyboardKeyCode key_code) {
-      static constexpr std::array<std::pair<KeyboardKeyCode, KeySym>, 45> special_keysyms {{
+      static constexpr std::array<std::pair<KeyboardKeyCode, KeySym>, 49> special_keysyms {{
         {0x08, XK_BackSpace},
         {0x09, XK_Tab},
         {0x0D, XK_Return},
@@ -2081,6 +2086,10 @@ namespace lvh::detail {
         {0xDC, XK_backslash},
         {0xDD, XK_bracketright},
         {0xDE, XK_apostrophe},
+        {0x0100, XK_Undo},
+        {0x0101, XF86XK_Cut},
+        {0x0102, XF86XK_Copy},
+        {0x0103, XF86XK_Paste},
       }};
 
       if (const auto keysym = mapped_keyboard_code(key_code, special_keysyms); keysym.has_value()) {
diff --git a/tests/unit/test_linux_backend.cpp b/tests/unit/test_linux_backend.cpp
index 70214eb..a2fa70a 100644
--- a/tests/unit/test_linux_backend.cpp
+++ b/tests/unit/test_linux_backend.cpp
@@ -19,6 +19,7 @@
 #include <linux/input.h>
 #if defined(LIBVIRTUALHID_HAVE_XTEST)
   #include <X11/keysym.h>
+  #include <X11/XF86keysym.h>
 #endif
 
 // lib includes
@@ -107,6 +108,10 @@ TEST_F(LinuxBackendTest, TranslatesKeyboardKeys) {
   EXPECT_EQ(lvh::detail::test::linux_key_code(0x70), KEY_F1);
   EXPECT_EQ(lvh::detail::test::linux_key_code(0x7B), KEY_F12);
   EXPECT_EQ(lvh::detail::test::linux_key_code(0x87), KEY_F24);
+  EXPECT_EQ(lvh::detail::test::linux_key_code(0x0100), KEY_UNDO);
+  EXPECT_EQ(lvh::detail::test::linux_key_code(0x0101), KEY_CUT);
+  EXPECT_EQ(lvh::detail::test::linux_key_code(0x0102), KEY_COPY);
+  EXPECT_EQ(lvh::detail::test::linux_key_code(0x0103), KEY_PASTE);
   EXPECT_EQ(lvh::detail::test::linux_key_code(0), -1);
   EXPECT_EQ(lvh::detail::test::linux_key_code(0x88), -1);
 }
@@ -1268,6 +1273,10 @@ TEST_F(LinuxBackendTest, XTestFallbackCoversKeyboardAndMousePaths) {
   EXPECT_EQ(lvh::detail::test::linux_xtest_keysym(0x6F), XK_KP_Divide);
   EXPECT_EQ(lvh::detail::test::linux_xtest_keysym(0x70), XK_F1);
   EXPECT_EQ(lvh::detail::test::linux_xtest_keysym(0x87), XK_F24);
+  EXPECT_EQ(lvh::detail::test::linux_xtest_keysym(0x0100), XK_Undo);
+  EXPECT_EQ(lvh::detail::test::linux_xtest_keysym(0x0101), XF86XK_Cut);
+  EXPECT_EQ(lvh::detail::test::linux_xtest_keysym(0x0102), XF86XK_Copy);
+  EXPECT_EQ(lvh::detail::test::linux_xtest_keysym(0x0103), XF86XK_Paste);
   EXPECT_EQ(lvh::detail::test::linux_xtest_keysym(0x88), 0UL);
 
   EXPECT_EQ(lvh::detail::test::linux_xtest_mouse_button(lvh::MouseButton::left), 1);