From 94010d6b9afae7d9dfde910cf18b81d148374426 Mon Sep 17 00:00:00 2001
From: TheOnlyMrCat <theonly@mrcat.au>
Date: Wed, 11 Oct 2023 20:24:10 +1000
Subject: [PATCH] events: Use xkbcommon for keyboard event handling (#43)

---
 CMakeLists.txt        |  2 +-
 nix/default.nix       |  2 ++
 src/events/Events.cpp | 47 ++++++++++++++++++++++++++++++++++++++++---
 src/hyprpicker.cpp    |  4 ++++
 src/hyprpicker.hpp    |  4 ++++
 src/includes.hpp      |  1 +
 6 files changed, 56 insertions(+), 4 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index f122158..edbf5ef 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -41,7 +41,7 @@ add_compile_options(-Wall -Wextra -Wno-unused-parameter -Wno-unused-value -Wno-m
 find_package(Threads REQUIRED)
 
 find_package(PkgConfig REQUIRED)
-pkg_check_modules(deps REQUIRED IMPORTED_TARGET wayland-client wayland-protocols cairo pango pangocairo libjpeg)
+pkg_check_modules(deps REQUIRED IMPORTED_TARGET wayland-client wayland-protocols xkbcommon cairo pango pangocairo libjpeg)
 
 file(GLOB_RECURSE SRCFILES "src/*.cpp")
 
diff --git a/nix/default.nix b/nix/default.nix
index f850743..85a9796 100644
--- a/nix/default.nix
+++ b/nix/default.nix
@@ -11,6 +11,7 @@
   libselinux,
   libsepol,
   libthai,
+  libxkbcommon,
   pango,
   pcre,
   utillinux,
@@ -50,6 +51,7 @@ stdenv.mkDerivation {
     wayland-scanner
     wlroots
     libXdmcp
+    libxkbcommon
     utillinux
   ];
 
diff --git a/src/events/Events.cpp b/src/events/Events.cpp
index ccf333e..b6d3006 100644
--- a/src/events/Events.cpp
+++ b/src/events/Events.cpp
@@ -246,10 +246,46 @@ void Events::handlePointerButton(void* data, struct wl_pointer* wl_pointer, uint
     g_pHyprpicker->finish();
 }
 
-void Events::handleKeyboardKeymap(void* data, wl_keyboard* wl_keyboard, uint format, int fd, uint size) {}
+void Events::handleKeyboardKeymap(void* data, wl_keyboard* wl_keyboard, uint format, int fd, uint size) {
+    if (!g_pHyprpicker->m_pXKBContext)
+        return;
+
+    if (format != WL_KEYBOARD_KEYMAP_FORMAT_XKB_V1) {
+        Debug::log(ERR, "Could not recognise keymap format");
+        return;
+    }
+
+    const char* buf = (const char*)mmap(NULL, size, PROT_READ, MAP_SHARED, fd, 0);
+    if (buf == MAP_FAILED) {
+        Debug::log(ERR, "Failed to mmap xkb keymap: %d", errno);
+        return;
+    }
+
+    g_pHyprpicker->m_pXKBKeymap = xkb_keymap_new_from_buffer(g_pHyprpicker->m_pXKBContext, buf, size - 1, XKB_KEYMAP_FORMAT_TEXT_V1, XKB_KEYMAP_COMPILE_NO_FLAGS);
+
+    munmap((void*)buf, size);
+    close(fd);
+
+    if (!g_pHyprpicker->m_pXKBKeymap) {
+        Debug::log(ERR, "Failed to compile xkb keymap");
+        return;
+    }
+
+    g_pHyprpicker->m_pXKBState = xkb_state_new(g_pHyprpicker->m_pXKBKeymap);
+    if (!g_pHyprpicker->m_pXKBState) {
+        Debug::log(ERR, "Failed to create xkb state");
+        return;
+    }
+}
 
 void Events::handleKeyboardKey(void* data, struct wl_keyboard* keyboard, uint32_t serial, uint32_t time, uint32_t key, uint32_t state) {
-    if (key == 1) // escape
+    if (state != WL_KEYBOARD_KEY_STATE_PRESSED)
+        return;
+
+    if (g_pHyprpicker->m_pXKBState) {
+        if (xkb_state_key_get_one_sym(g_pHyprpicker->m_pXKBState, key + 8) == XKB_KEY_Escape)
+            g_pHyprpicker->finish();
+    } else if (key == 1) // Assume keycode 1 is escape
         g_pHyprpicker->finish();
 }
 
@@ -257,7 +293,12 @@ void Events::handleKeyboardEnter(void* data, wl_keyboard* wl_keyboard, uint seri
 
 void Events::handleKeyboardLeave(void* data, wl_keyboard* wl_keyboard, uint serial, wl_surface* surface) {}
 
-void Events::handleKeyboardModifiers(void* data, wl_keyboard* wl_keyboard, uint serial, uint mods_depressed, uint mods_latched, uint mods_locked, uint group) {}
+void Events::handleKeyboardModifiers(void* data, wl_keyboard* wl_keyboard, uint serial, uint mods_depressed, uint mods_latched, uint mods_locked, uint group) {
+    if (!g_pHyprpicker->m_pXKBState)
+        return;
+
+    xkb_state_update_mask(g_pHyprpicker->m_pXKBState, mods_depressed, mods_latched, mods_locked, 0, 0, group);
+}
 
 void Events::handleFrameDone(void* data, struct wl_callback* callback, uint32_t time) {
     CLayerSurface* pLS = (CLayerSurface*)data;
diff --git a/src/hyprpicker.cpp b/src/hyprpicker.cpp
index 6c3d0d9..3fa657c 100644
--- a/src/hyprpicker.cpp
+++ b/src/hyprpicker.cpp
@@ -8,6 +8,10 @@ void sigHandler(int sig) {
 }
 
 void CHyprpicker::init() {
+    m_pXKBContext = xkb_context_new(XKB_CONTEXT_NO_FLAGS);
+    if (!m_pXKBContext)
+        Debug::log(ERR, "Failed to create xkb context");
+
     m_pWLDisplay = wl_display_connect(nullptr);
 
     if (!m_pWLDisplay) {
diff --git a/src/hyprpicker.hpp b/src/hyprpicker.hpp
index 17fd15c..60a8851 100644
--- a/src/hyprpicker.hpp
+++ b/src/hyprpicker.hpp
@@ -26,6 +26,10 @@ class CHyprpicker {
     zwlr_layer_shell_v1*                        m_pLayerShell;
     zwlr_screencopy_manager_v1*                 m_pSCMgr;
 
+    xkb_context*                                m_pXKBContext = nullptr;
+    xkb_keymap*                                 m_pXKBKeymap  = nullptr;
+    xkb_state*                                  m_pXKBState   = nullptr;
+
     eOutputMode                                 m_bSelectedOutputMode = OUTPUT_HEX;
 
     bool                                        m_bFancyOutput = true;
diff --git a/src/includes.hpp b/src/includes.hpp
index 4dff159..9890344 100644
--- a/src/includes.hpp
+++ b/src/includes.hpp
@@ -40,6 +40,7 @@ extern "C" {
 #include <sys/mman.h>
 #include <unistd.h>
 #include <wayland-client.h>
+#include <xkbcommon/xkbcommon.h>
 
 #include <algorithm>
 #include <filesystem>