Kernel+LibKeyboard: Enable querying the current keymap

Kernel/Syscalls/keymap.cpp

@@ -0,0 +1,100 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <Kernel/Devices/KeyboardDevice.h>
+#include <Kernel/Process.h>
+
+namespace Kernel {
+
+constexpr size_t map_name_max_size = 50;
+
+int Process::sys$setkeymap(Userspace<const Syscall::SC_setkeymap_params*> user_params)
+{
+    REQUIRE_PROMISE(setkeymap);
+
+    if (!is_superuser())
+        return -EPERM;
+
+    Syscall::SC_setkeymap_params params;
+    if (!copy_from_user(&params, user_params))
+        return -EFAULT;
+
+    Keyboard::CharacterMapData character_map_data;
+
+    if (!copy_from_user(character_map_data.map, params.map, CHAR_MAP_SIZE * sizeof(u32)))
+        return -EFAULT;
+    if (!copy_from_user(character_map_data.shift_map, params.shift_map, CHAR_MAP_SIZE * sizeof(u32)))
+        return -EFAULT;
+    if (!copy_from_user(character_map_data.alt_map, params.alt_map, CHAR_MAP_SIZE * sizeof(u32)))
+        return -EFAULT;
+    if (!copy_from_user(character_map_data.altgr_map, params.altgr_map, CHAR_MAP_SIZE * sizeof(u32)))
+        return -EFAULT;
+    if (!copy_from_user(character_map_data.shift_altgr_map, params.shift_altgr_map, CHAR_MAP_SIZE * sizeof(u32)))
+        return -EFAULT;
+
+    auto map_name = get_syscall_path_argument(params.map_name);
+    if (map_name.is_error()) {
+        return map_name.error();
+    }
+    if (map_name.value().length() > map_name_max_size) {
+        return -ENAMETOOLONG;
+    }
+
+    KeyboardDevice::the().set_maps(character_map_data, map_name.value());
+    return 0;
+}
+
+int Process::sys$getkeymap(Userspace<const Syscall::SC_getkeymap_params*> user_params)
+{
+    REQUIRE_PROMISE(stdio);
+
+    Syscall::SC_getkeymap_params params;
+    if (!copy_from_user(&params, user_params))
+        return -EFAULT;
+
+    String keymap_name = KeyboardDevice::the().keymap_name();
+    const Keyboard::CharacterMapData& character_maps = KeyboardDevice::the().character_maps();
+
+    if (!copy_to_user(params.map, character_maps.map, CHAR_MAP_SIZE * sizeof(u32)))
+        return -EFAULT;
+    if (!copy_to_user(params.shift_map, character_maps.shift_map, CHAR_MAP_SIZE * sizeof(u32)))
+        return -EFAULT;
+    if (!copy_to_user(params.alt_map, character_maps.alt_map, CHAR_MAP_SIZE * sizeof(u32)))
+        return -EFAULT;
+    if (!copy_to_user(params.altgr_map, character_maps.altgr_map, CHAR_MAP_SIZE * sizeof(u32)))
+        return -EFAULT;
+    if (!copy_to_user(params.shift_altgr_map, character_maps.shift_altgr_map, CHAR_MAP_SIZE * sizeof(u32)))
+        return -EFAULT;
+
+    if (params.map_name.size < keymap_name.length())
+        return -ENAMETOOLONG;
+    if (!copy_to_user(params.map_name.data, keymap_name.characters(), keymap_name.length()))
+        return -EFAULT;
+
+    return 0;
+}
+
+}