build: Avoid MaybeUninit on older Debian

Key maps are switched on key press whenever needed.

Cargo.toml.in

@@ -19,6 +19,7 @@ path = "@path@/examples/test_layout.rs"
 [features]
 gio_v0_5 = []
 gtk_v0_5 = []
+rustc_less_1_36 = []
 
 # Dependencies which don't change based on build flags
 [dependencies.cairo-sys-rs]

README.md

@@ -30,29 +30,42 @@ Building
 
 ### Dependencies
 
-See `.gitlab-ci.yml`.
+See `.gitlab-ci.yml` or run `apt-get build-dep .`
 
 ### Build from git repo
 
-```
+```bash
 $ git clone https://source.puri.sm/Librem5/squeekboard.git
 $ cd squeekboard
-$ mkdir ../build
-$ meson ../build/
-$ cd ../build
-$ ninja test
-$ ninja install
+$ mkdir _build
+$ meson _build/
+$ cd _build
+$ ninja
 ```
 
+To run tests use `ninja test`. To install squeekboard run `ninja install`.
+
 Running
 -------
 
-```
+```bash
 $ phoc # if no compatible Wayland compositor is running yet
 $ cd ../build/
 $ src/squeekboard
 ```
 
+Squeekboard honors the gnome "screen-keyboard-enabled" setting. Either enable this through gnome-settings under accessibility or run:
+
+```bash
+$ gsettings set org.gnome.desktop.a11y.applications screen-keyboard-enabled true
+```
+
+To make the keyboard show you can use either an application that does so automatically, like a text editor or `python3 ./tests/entry.py`, or you can manually trigger it with:
+
+```bash
+busctl call --user sm.puri.OSK0 /sm/puri/OSK0 sm.puri.OSK0 SetVisible b true
+```
+
 Developing
 ----------
 

data/keyboards/be.yaml

@@ -0,0 +1,89 @@
+---
+outlines:
+    default:   { width: 35.33, height: 52 }
+    altline:   { width: 52.67, height: 52 }
+    wide:      { width: 59,    height: 52 }
+    spaceline: { width: 140,   height: 52 }
+    special:   { width: 44,    height: 52 }
+
+views:
+    base:
+        - "a z e r t y u i o p"
+        - "q s d f g h j k l m"
+        - "Shift_L   w x c v b n .   BackSpace"
+        - "show_numbers preferences         space        show_eschars Return"
+    upper:
+        - "A Z E R T Y U I O P"
+        - "Q S D F G H J K L M"
+        - "Shift_L   W X C V B N ,  BackSpace"
+        - "show_numbers preferences         space        show_eschars Return"
+    numbers:
+        - "1 2 3 4 5 6 7 8 9 0"
+        - "@ # € % & - _ + ( )"
+        - "show_symbols   , \" ' colon ; ! ?  BackSpace"
+        - "show_letters preferences         space        show_eschars Return"
+    symbols:
+        - "~ ` | · √ π τ ÷ × ¶"
+        - "© ® £ $ ¥ ^ ° * { }"
+        - "show_numbers_from_symbols   \\ / < > = [ ]  BackSpace"
+        - "show_letters preferences         space        show_eschars Return"
+    eschars:
+        - "à â ç é è ê î ô ù û"
+        - "À Â Ç É È Ê Î Ô Ù Û"
+        - "show_numbers_from_symbols  æ œ ä ë ï ö ü  BackSpace"
+        - "show_letters preferences         space        show_eschars Return"
+
+buttons:
+    Shift_L:
+        action:
+            locking:
+                lock_view: "upper"
+                unlock_view: "base"
+        outline: "altline"
+        icon: "key-shift"
+    BackSpace:
+        outline: "altline"
+        icon: "edit-clear-symbolic"
+        action: erase
+    preferences:
+        action: "show_prefs"
+        outline: "special"
+        icon: "keyboard-mode-symbolic"
+    show_numbers:
+        action:
+            set_view: "numbers"
+        outline: "wide"
+        label: "123"
+    show_numbers_from_symbols:
+        action:
+            set_view: "numbers"
+        outline: "altline"
+        label: "123"
+    show_letters:
+        action:
+            set_view: "base"
+        outline: "wide"
+        label: "abc"
+    show_symbols:
+        action:
+            set_view: "symbols"
+        outline: "altline"
+        label: "*/="
+    show_eschars:
+        action:
+            locking:
+                lock_view: "eschars"
+                unlock_view: "base"
+        outline: "altline"
+        label: "âÂ"
+    space:
+        outline: "spaceline"
+        text: " "
+    Return:
+        outline: "wide"
+        icon: "key-enter"
+        keysym: "Return"
+    colon:
+        text: ":"
+    "\"":
+        keysym: "quotedbl"

doc/hacking.md

@@ -13,16 +13,16 @@ The overarching principle of *squeekboard* is to empower users.
 Software is primarily meant to solve problems of its users. Often in the quest to make software better, a hard distinction is made between the developer, who becomes the creator, and the user, who takes the role of the consumer, without direct influence on the software they use.
 This project aims to give users the power to make the software work for them by blurring the lines between users and developers.
 
-Nonwithstanding its current state, *squeekboard* must be structured in a way that provides users a gradual way to gain more experience and power to adjust it. It must be easy, in order of importance:
+Notwithstanding its current state, *squeekboard* must be structured in a way that provides users a gradual way to gain more experience and power to adjust it. It must be easy, in order of importance:
 
 - to use the software,
 - to modify its resources,
-- to change its behaviour,
+- to change its behavior,
 - to contribute upstream.
 
 To give an idea of what it means in practice, those are some examples of what has been important for *squeekboard* so far:
 
-- being quick and useable,
+- being quick and usable,
 - allowing local overrides of resources and config,
 - storing resources and config as editable, standard files,
 - having complete, up to date documentation of interfaces,
@@ -33,7 +33,7 @@ To give an idea of what it means in practice, those are some examples of what ha
 - having code that is [simple and obvious](https://www.python.org/dev/peps/pep-0020/),
 - having an easy process of testing and accepting contributions.
 
-You may notice that they are ordered roughly from "user-focused" to "maintainer-focused". While good properties are desired, sometimes they conflict, and maintainers should give additional weight to those benefitting the user compared to those benefitting regular contributors.
+You may notice that they are ordered roughly from "user-focused" to "maintainer-focused". While good properties are desired, sometimes they conflict, and maintainers should give additional weight to those benefiting the user compared to those benefiting regular contributors.
 
 Sending patches
 ---------------
@@ -43,7 +43,7 @@ By submitting a change to this project, you agree to license it under the [GPL l
 Development environment
 -----------------------
 
-*Squeekboard* is regularly built and tested on [the develpment environment](https://developer.puri.sm/Librem5/Development_Environment.html).
+*Squeekboard* is regularly built and tested on [the development environment](https://developer.puri.sm/Librem5/Development_Environment.html).
 
 Recent Fedora releases are likely to be tested as well.
 
@@ -162,7 +162,7 @@ Maintenance
 
 Squeekboard uses Rust & Cargo for some of its dependencies.
 
-Use the `cargo.sh` script for maintaining the Cargo part of the build. The script takes the usual Cargo commands, after the first 2 positionsl arguments: source directory, and output artifact. So, `cargo test` becomes:
+Use the `cargo.sh` script for maintaining the Cargo part of the build. The script takes the usual Cargo commands, after the first 2 positional arguments: source directory, and output artifact. So, `cargo test` becomes:
 
 ```
 cd build_dir

eek/eek-gtk-keyboard.c

@@ -360,6 +360,10 @@ eek_gtk_keyboard_init (EekGtkKeyboard *self)
         priv->event = lfb_event_new ("button-pressed");
     else
         g_warning ("Failed to init libfeedback: %s", err->message);
+
+    GtkIconTheme *theme = gtk_icon_theme_get_default ();
+
+    gtk_icon_theme_add_resource_path (theme, "/sm/puri/squeekboard/icons");
 }
 
 static void

eek/eek-keyboard.c

@@ -31,30 +31,19 @@
 
 #include "eek-keyboard.h"
 
-void level_keyboard_free(LevelKeyboard *self) {
-    xkb_keymap_unref(self->keymap);
-    close(self->keymap_fd);
-    squeek_layout_free(self->layout);
-    g_free(self);
+/// External linkage for Rust.
+/// Don't call multiple times on the same copy, just in Drop.
+void eek_key_map_deinit(struct KeyMap *self) {
+    close(self->fd);
 }
 
-LevelKeyboard*
-level_keyboard_new (struct squeek_layout *layout)
-{
-    LevelKeyboard *keyboard = g_new0(LevelKeyboard, 1);
-
-    if (!keyboard) {
-        g_error("Failed to create a keyboard");
-    }
-    keyboard->layout = layout;
-
+/// External linkage for Rust.
+struct KeyMap eek_key_map_from_str(char *keymap_str) {
     struct xkb_context *context = xkb_context_new(XKB_CONTEXT_NO_FLAGS);
     if (!context) {
         g_error("No context created");
     }
 
-    const gchar *keymap_str = squeek_layout_get_keymap(keyboard->layout);
-
     struct xkb_keymap *keymap = xkb_keymap_new_from_string(context, keymap_str,
         XKB_KEYMAP_FORMAT_TEXT_V1, XKB_KEYMAP_COMPILE_NO_FLAGS);
 
@@ -62,10 +51,9 @@ level_keyboard_new (struct squeek_layout *layout)
         g_error("Bad keymap:\n%s", keymap_str);
 
     xkb_context_unref(context);
-    keyboard->keymap = keymap;
 
-    keymap_str = xkb_keymap_get_as_string(keymap, XKB_KEYMAP_FORMAT_TEXT_V1);
-    keyboard->keymap_len = strlen(keymap_str) + 1;
+    char *xkb_keymap_str = xkb_keymap_get_as_string(keymap, XKB_KEYMAP_FORMAT_TEXT_V1);
+    size_t keymap_len = strlen(xkb_keymap_str) + 1;
 
     g_autofree char *path = strdup("/eek_keymap-XXXXXX");
     char *r = &path[strlen(path) - 6];
@@ -79,17 +67,39 @@ level_keyboard_new (struct squeek_layout *layout)
     if (keymap_fd < 0) {
         g_error("Failed to set up keymap fd");
     }
-    keyboard->keymap_fd = keymap_fd;
+
     shm_unlink(path);
-    if (ftruncate(keymap_fd, (off_t)keyboard->keymap_len)) {
+    if (ftruncate(keymap_fd, (off_t)keymap_len)) {
         g_error("Failed to increase keymap fd size");
     }
-    char *ptr = mmap(NULL, keyboard->keymap_len, PROT_WRITE, MAP_SHARED,
+    char *ptr = mmap(NULL, keymap_len, PROT_WRITE, MAP_SHARED,
         keymap_fd, 0);
     if ((void*)ptr == (void*)-1) {
         g_error("Failed to set up mmap");
     }
-    strncpy(ptr, keymap_str, keyboard->keymap_len);
-    munmap(ptr, keyboard->keymap_len);
+    strncpy(ptr, xkb_keymap_str, keymap_len);
+    munmap(ptr, keymap_len);
+    free(xkb_keymap_str);
+    xkb_keymap_unref(keymap);
+    struct KeyMap km = {
+        .fd = keymap_fd,
+        .fd_len = keymap_len,
+    };
+    return km;
+}
+
+void level_keyboard_free(LevelKeyboard *self) {
+    squeek_layout_free(self->layout);
+    g_free(self);
+}
+
+LevelKeyboard*
+level_keyboard_new (struct squeek_layout *layout)
+{
+    LevelKeyboard *keyboard = g_new0(LevelKeyboard, 1);
+    if (!keyboard) {
+        g_error("Failed to create a keyboard");
+    }
+    keyboard->layout = layout;
     return keyboard;
 }

eek/eek-keyboard.h

@@ -35,16 +35,18 @@ G_BEGIN_DECLS
 /// Keyboard state holder
 struct _LevelKeyboard {
     struct squeek_layout *layout; // owned
-    struct xkb_keymap *keymap; // owned
-    int keymap_fd; // keymap formatted as XKB string
-    size_t keymap_len; // length of the data inside keymap_fd
-
+// FIXME: This no longer needs to exist, keymap was folded into layout.
     guint id; // as a key to layout choices
 };
 typedef struct _LevelKeyboard LevelKeyboard;
 
-gchar *             eek_keyboard_get_keymap
-                                     (LevelKeyboard *keyboard);
+/// Keymap container for Rust interoperability.
+struct KeyMap {
+    uint32_t fd; // keymap formatted as XKB string
+    size_t fd_len; // length of the data inside keymap_fd
+};
+
+gchar *eek_keyboard_get_keymap(LevelKeyboard *keyboard);
 
 LevelKeyboard*
 level_keyboard_new (struct squeek_layout *layout);

eek/eek-renderer.c

@@ -265,10 +265,6 @@ renderer_init (EekRenderer *self)
     self->allocation_height = 0.0;
     self->scale_factor = 1;
 
-    GtkIconTheme *theme = gtk_icon_theme_get_default ();
-
-    gtk_icon_theme_add_resource_path (theme, "/sm/puri/squeekboard/icons");
-
     self->css_provider = squeek_load_style();
 }
 

eekboard/eekboard-context-service.c

@@ -159,7 +159,7 @@ eekboard_context_service_use_layout(EekboardContextService *context, struct sque
     // Update the keymap if necessary.
     // TODO: Update submission on change event
     if (context->submission) {
-        submission_set_keyboard(context->submission, keyboard, timestamp);
+        submission_use_layout(context->submission, keyboard->layout, timestamp);
     }
 
     // Update UI
@@ -345,7 +345,7 @@ void eekboard_context_service_set_submission(EekboardContextService *context, st
     context->submission = submission;
     if (context->submission) {
         uint32_t time = gdk_event_get_time(NULL);
-        submission_set_keyboard(context->submission, context->keyboard, time);
+        submission_use_layout(context->submission, context->keyboard->layout, time);
     }
 }
 

examples/test_layout.rs

@@ -5,6 +5,7 @@ use std::env;
 
 fn main() -> () {
     check_builtin_layout(
-        env::args().nth(1).expect("No argument given").as_str()
+        env::args().nth(1).expect("No argument given").as_str(),
+        env::args().nth(2).map(|s| s == "allow_missing_return").unwrap_or(false),
     );
 }

meson.build

@@ -83,7 +83,7 @@ cargo_toml_base = configure_file(
 cargo_deps = files('Cargo.deps')
 
 if get_option('legacy') == true
-    cargo_build_flags += ['--features', 'gtk_v0_5,gio_v0_5']
+    cargo_build_flags += ['--features', 'gtk_v0_5,gio_v0_5,rustc_less_1_36']
     cargo_deps = files('Cargo.deps.legacy')
 endif
     

src/data.rs

@@ -18,7 +18,7 @@ use xkbcommon::xkb;
 use ::action;
 use ::keyboard::{
     KeyState, PressType,
-    generate_keymap, generate_keycodes, FormattingError
+    generate_keymaps, generate_keycodes, KeyCode, FormattingError
 };
 use ::layout;
 use ::layout::ArrangementKind;
@@ -382,56 +382,45 @@ impl Layout {
                 )
             )}).collect();
 
-        let keymap: HashMap<String, u32> = generate_keycodes(
-            button_actions.iter()
-                .filter_map(|(_name, action)| {
-                    match action {
-                        ::action::Action::Submit {
-                            text: _, keys,
-                        } => Some(keys),
-                        _ => None,
-                    }
-                })
-                .flatten()
-                .map(|named_keysym| named_keysym.0.as_str())
+        let symbolmap: HashMap<String, KeyCode> = generate_keycodes(
+            extract_symbol_names(&button_actions)
         );
 
-        let button_states = button_actions.into_iter().map(|(name, action)| {
-            let keycodes = match &action {
-                ::action::Action::Submit { text: _, keys } => {
-                    keys.iter().map(|named_keycode| {
-                        *keymap.get(named_keycode.0.as_str())
-                            .expect(
-                                format!(
-                                    "keycode {} in key {} missing from keymap",
-                                    named_keycode.0,
-                                    name
-                                ).as_str()
-                            )
-                    }).collect()
-                },
-                action::Action::Erase => vec![
-                    *keymap.get("BackSpace")
-                        .expect(&format!("BackSpace missing from keymap")),
-                ],
-                _ => Vec::new(),
-            };
-            (
-                name.into(),
-                KeyState {
-                    pressed: PressType::Released,
-                    keycodes,
-                    action,
-                }
-            )
-        });
-
         let button_states = HashMap::<String, KeyState>::from_iter(
-            button_states
+            button_actions.into_iter().map(|(name, action)| {
+                let keycodes = match &action {
+                    ::action::Action::Submit { text: _, keys } => {
+                        keys.iter().map(|named_keysym| {
+                            symbolmap.get(named_keysym.0.as_str())
+                                .expect(
+                                    format!(
+                                        "keysym {} in key {} missing from symbol map",
+                                        named_keysym.0,
+                                        name
+                                    ).as_str()
+                                )
+                                .clone()
+                        }).collect()
+                    },
+                    action::Action::Erase => vec![
+                        symbolmap.get("BackSpace")
+                            .expect(&format!("BackSpace missing from symbol map"))
+                            .clone(),
+                    ],
+                    _ => Vec::new(),
+                };
+                (
+                    name.into(),
+                    KeyState {
+                        pressed: PressType::Released,
+                        keycodes,
+                        action,
+                    }
+                )
+            })
         );
 
-        // TODO: generate from symbols
-        let keymap_str = match generate_keymap(&button_states) {
+        let keymaps = match generate_keymaps(symbolmap) {
             Err(e) => { return (Err(e), warning_handler) },
             Ok(v) => v,
         };
@@ -495,10 +484,10 @@ impl Layout {
         (
             Ok(::layout::LayoutData {
                 views: views,
-                keymap_str: {
+                keymaps: keymaps.into_iter().map(|keymap_str|
                     CString::new(keymap_str)
                         .expect("Invalid keymap string generated")
-                },
+                ).collect(),
                 // FIXME: use a dedicated field
                 margins: layout::Margins {
                     top: self.margins.top,
@@ -734,11 +723,27 @@ fn create_button<H: logging::Handler>(
     }
 }
 
+fn extract_symbol_names<'a>(actions: &'a [(&str, action::Action)])
+    -> impl Iterator<Item=String> + 'a
+{
+    actions.iter()
+        .filter_map(|(_name, act)| {
+            match act {
+                action::Action::Submit {
+                    text: _, keys,
+                } => Some(keys.clone()),
+                action::Action::Erase => Some(vec!(action::KeySym("BackSpace".into()))),
+                _ => None,
+            }
+        })
+        .flatten()
+        .map(|named_keysym| named_keysym.0)
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
-    
-    use std::error::Error as ErrorTrait;
+
     use ::logging::ProblemPanic;
 
     const THIS_FILE: &str = file!();
@@ -786,7 +791,8 @@ mod tests {
             Err(e) => {
                 let mut handled = false;
                 if let Error::Yaml(ye) = &e {
-                    handled = ye.description() == "missing field `views`";
+                    handled = ye.to_string()
+                        .starts_with("missing field `views`");
                 };
                 if !handled {
                     println!("Unexpected error {:?}", e);
@@ -804,7 +810,7 @@ mod tests {
             Err(e) => {
                 let mut handled = false;
                 if let Error::Yaml(ye) = &e {
-                    handled = ye.description()
+                    handled = ye.to_string()
                         .starts_with("unknown field `bad_field`");
                 };
                 if !handled {
@@ -862,6 +868,23 @@ mod tests {
         );
     }
 
+    /// Test if erase yields a useable keycode
+    #[test]
+    fn test_layout_erase() {
+        let out = Layout::from_file(path_from_root("tests/layout_erase.yaml"))
+            .unwrap()
+            .build(ProblemPanic).0
+            .unwrap();
+        assert_eq!(
+            out.views["base"].1
+                .get_rows()[0].1
+                .buttons[0].1
+                .state.borrow()
+                .keycodes.len(),
+            1
+        );
+    }
+
     #[test]
     fn parsing_fallback() {
         assert!(Layout::from_resource(FALLBACK_LAYOUT_NAME)
@@ -939,4 +962,35 @@ mod tests {
             }
         );
     }
+
+    #[test]
+    fn test_extract_symbols() {
+        let actions = [(
+            "ac",
+            action::Action::Submit {
+                text: None,
+                keys: vec![
+                    action::KeySym("a".into()),
+                    action::KeySym("c".into()),
+                ],
+            },
+        )];
+        assert_eq!(
+            extract_symbol_names(&actions[..]).collect::<Vec<_>>(),
+            vec!["a", "c"],
+        );
+    }
+
+    #[test]
+    fn test_extract_symbols_erase() {
+        let actions = [(
+            "Erase",
+            action::Action::Erase,
+        )];
+        assert_eq!(
+            extract_symbol_names(&actions[..]).collect::<Vec<_>>(),
+            vec!["BackSpace"],
+        );
+    }
+
 }

src/keyboard.rs

@@ -5,11 +5,13 @@ use std::cell::RefCell;
 use std::collections::HashMap;
 use std::fmt;
 use std::io;
+use std::mem;
+use std::ptr;
 use std::rc::Rc;
 use std::string::FromUtf8Error;
 
 use ::action::Action;
-use ::logging;
+use ::util;
 
 // Traits
 use std::io::Write;
@@ -21,7 +23,12 @@ pub enum PressType {
     Pressed = 1,
 }
 
-pub type KeyCode = u32;
+/// The extended, unambiguous layout-keycode
+#[derive(Debug, Clone)]
+pub struct KeyCode {
+    pub code: u32,
+    pub keymap_idx: usize,
+}
 
 bitflags!{
     /// Map to `virtual_keyboard.modifiers` modifiers values
@@ -80,10 +87,10 @@ impl KeyState {
 }
 
 /// Sorts an iterator by converting it to a Vector and back
-fn sorted<'a, I: Iterator<Item=&'a str>>(
+fn sorted<'a, I: Iterator<Item=String>>(
     iter: I
-) -> impl Iterator<Item=&'a str> {
-    let mut v: Vec<&'a str> = iter.collect();
+) -> impl Iterator<Item=String> {
+    let mut v: Vec<String> = iter.collect();
     v.sort();
     v.into_iter()
 }
@@ -91,15 +98,17 @@ fn sorted<'a, I: Iterator<Item=&'a str>>(
 /// Generates a mapping where each key gets a keycode, starting from ~~8~~
 /// HACK: starting from 9, because 8 results in keycode 0,
 /// which the compositor likes to discard
-pub fn generate_keycodes<'a, C: IntoIterator<Item=&'a str>>(
-    key_names: C
-) -> HashMap<String, u32> {
-    let special_keysyms = ["BackSpace", "Return"].iter().map(|&s| s);
+pub fn generate_keycodes<'a, C: IntoIterator<Item=String>>(
+    key_names: C,
+) -> HashMap<String, KeyCode> {
     HashMap::from_iter(
-        // sort to remove a source of indeterminism in keycode assignment
-        sorted(key_names.into_iter().chain(special_keysyms))
-            .map(|name| String::from(name))
-            .zip(9..)
+        // Sort to remove a source of indeterminism in keycode assignment.
+        sorted(key_names.into_iter())
+            .zip(util::cycle_count(9..255))
+            .map(|(name, (code, keymap_idx))| (
+                String::from(name),
+                KeyCode { code, keymap_idx },
+            ))
     )
 }
 
@@ -124,12 +133,54 @@ impl From<io::Error> for FormattingError {
     }
 }
 
+/// Index is the key code, String is the occupant.
+/// Starts all empty.
+/// https://gitlab.freedesktop.org/xorg/xserver/-/issues/260
+type SingleKeyMap = [Option<String>; 256];
+
+fn single_key_map_new() -> SingleKeyMap {
+    // Why can't we just initialize arrays without tricks -_- ?
+    unsafe {
+        // Inspired by
+        // https://www.reddit.com/r/rust/comments/5n7bh1/how_to_create_an_array_of_a_type_with_clone_but/
+        #[cfg(feature = "rustc_less_1_36")]
+        let mut array: SingleKeyMap = mem::uninitialized();
+        #[cfg(not(feature = "rustc_less_1_36"))]
+        let mut array: SingleKeyMap = mem::MaybeUninit::uninit().assume_init();
+
+        for element in array.iter_mut() {
+            ptr::write(element, None);
+        }
+        array
+    }
+}
+
+pub fn generate_keymaps(symbolmap: HashMap::<String, KeyCode>)
+    -> Result<Vec<String>, FormattingError>
+{
+    let mut bins: Vec<SingleKeyMap> = Vec::new();
+    
+    for (name, KeyCode { code, keymap_idx }) in symbolmap.into_iter() {
+        if keymap_idx >= bins.len() {
+            bins.resize_with(
+                keymap_idx + 1,
+                || single_key_map_new(),
+            );
+        }
+        bins[keymap_idx][code as usize] = Some(name);
+    }
+
+    let mut out = Vec::new();
+    for bin in bins {
+        out.push(generate_keymap(&bin)?);
+    }
+    Ok(out)
+}
+
 /// Generates a de-facto single level keymap.
-// TODO: don't rely on keys and their order,
-// but rather on what keysyms and keycodes are in use.
-// Iterating actions makes it hard to deduplicate keysyms.
-pub fn generate_keymap(
-    keystates: &HashMap::<String, KeyState>
+/// Key codes must not repeat and must remain between 9 and 255.
+fn generate_keymap(
+    symbolmap: &SingleKeyMap,
 ) -> Result<String, FormattingError> {
     let mut buf: Vec<u8> = Vec::new();
     writeln!(
@@ -140,86 +191,80 @@ pub fn generate_keymap(
         minimum = 8;
         maximum = 255;"
     )?;
+
+    let pairs: Vec<(&String, usize)> = symbolmap.iter()
+        // Attach a key code to each cell.
+        .enumerate()
+        // Get rid of empty keycodes.
+        .filter_map(|(code, name)| name.as_ref().map(|n| (n, code)))
+        .collect();
     
-    for (name, state) in keystates.iter() {
-        match &state.action {
-            Action::Submit { text: _, keys } => {
-                if let 0 = keys.len() {
-                    log_print!(
-                        logging::Level::Warning,
-                        "Key {} has no keysyms", name,
-                    );
-                };
-                for (named_keysym, keycode) in keys.iter().zip(&state.keycodes) {
-                    write!(
-                        buf,
-                        "
-        <{}> = {};",
-                        named_keysym.0,
-                        keycode,
-                    )?;
-                }
-            },
-            Action::Erase => {
-                let mut keycodes = state.keycodes.iter();
-                write!(
-                    buf,
-                    "
-        <BackSpace> = {};",
-                    keycodes.next().expect("Erase key has no keycode"),
-                )?;
-                if let Some(_) = keycodes.next() {
-                    log_print!(
-                        logging::Level::Bug,
-                        "Erase key has multiple keycodes",
-                    );
-                }
-            },
-            _ => {},
-        }
+    // Xorg can only consume up to 255 keys, so this may not work in Xwayland.
+    // Two possible solutions:
+    // - use levels to cram multiple characters into one key
+    // - swap layouts on key presses
+    for (_name, keycode) in &pairs {
+        write!(
+            buf,
+            "
+        <I{}> = {0};",
+            keycode,
+        )?;
     }
-    
+
     writeln!(
         buf,
         "
+        indicator 1 = \"Caps Lock\"; // Xwayland won't accept without it.
     }};
     
     xkb_symbols \"squeekboard\" {{
-
-        name[Group1] = \"Letters\";
-        name[Group2] = \"Numbers/Symbols\";
-        
-        key <BackSpace> {{ [ BackSpace ] }};"
+"
     )?;
     
-    for (_name, state) in keystates.iter() {
-        if let Action::Submit { text: _, keys } = &state.action {
-            for keysym in keys.iter() {
-                write!(
-                    buf,
-                    "
-        key <{}> {{ [ {0} ] }};",
-                    keysym.0,
-                )?;
-            }
-        }
+    for (name, keycode) in pairs {
+        write!(
+            buf,
+            "
+key <I{}> {{ [ {} ] }};",
+            keycode,
+            name,
+        )?;
     }
+
     writeln!(
         buf,
         "
     }};
 
     xkb_types \"squeekboard\" {{
+        virtual_modifiers Squeekboard; // No modifiers! Needed for Xorg for some reason.
+    
+        // Those names are needed for Xwayland.
+        type \"ONE_LEVEL\" {{
+            modifiers= none;
+            level_name[Level1]= \"Any\";
+        }};
+        type \"TWO_LEVEL\" {{
+            level_name[Level1]= \"Base\";
+        }};
+        type \"ALPHABETIC\" {{
+            level_name[Level1]= \"Base\";
+        }};
+        type \"KEYPAD\" {{
+            level_name[Level1]= \"Base\";
+        }};
+        type \"SHIFT+ALT\" {{
+            level_name[Level1]= \"Base\";
+        }};
 
-	type \"TWO_LEVEL\" {{
-            modifiers = Shift;
-            map[Shift] = Level2;
-            level_name[Level1] = \"Base\";
-            level_name[Level2] = \"Shift\";
-	}};
     }};
 
     xkb_compatibility \"squeekboard\" {{
+        // Needed for Xwayland again.
+        interpret Any+AnyOf(all) {{
+            action= SetMods(modifiers=modMapMods,clearLocks);
+        }};
     }};
 }};"
     )?;
@@ -234,22 +279,15 @@ mod tests {
     
     use xkbcommon::xkb;
 
-    use ::action::KeySym;
-
     #[test]
-    fn test_keymap_multi() {
-        let context = xkb::Context::new(xkb::CONTEXT_NO_FLAGS);
+    fn test_keymap_single_resolve() {
+        let mut key_map = single_key_map_new();
+        key_map[9] = Some("a".into());
+        key_map[10] = Some("c".into());
 
-        let keymap_str = generate_keymap(&hashmap!{
-            "ac".into() => KeyState {
-                action: Action::Submit {
-                    text: None,
-                    keys: vec!(KeySym("a".into()), KeySym("c".into())),
-                },
-                keycodes: vec!(9, 10),
-                pressed: PressType::Released,
-            },
-        }).unwrap();
+        let keymap_str = generate_keymap(&key_map).unwrap();
+
+        let context = xkb::Context::new(xkb::CONTEXT_NO_FLAGS);
 
         let keymap = xkb::Keymap::new_from_string(
             &context,
@@ -263,4 +301,36 @@ mod tests {
         assert_eq!(state.key_get_one_sym(9), xkb::KEY_a);
         assert_eq!(state.key_get_one_sym(10), xkb::KEY_c);
     }
+
+    #[test]
+    fn test_keymap_second_resolve() {
+        let keymaps = generate_keymaps(hashmap!(
+            "a".into() => KeyCode { keymap_idx: 1, code: 9 },
+        )).unwrap();
+
+        let context = xkb::Context::new(xkb::CONTEXT_NO_FLAGS);
+
+        let keymap = xkb::Keymap::new_from_string(
+            &context,
+            keymaps[1].clone(), // this index is part of the test
+            xkb::KEYMAP_FORMAT_TEXT_V1,
+            xkb::KEYMAP_COMPILE_NO_FLAGS,
+        ).expect("Failed to create keymap");
+
+        let state = xkb::State::new(&keymap);
+
+        assert_eq!(state.key_get_one_sym(9), xkb::KEY_a);
+    }
+
+    #[test]
+    fn test_symbolmap_overflow() {
+        // The 257th key (U1101) is interesting.
+        // Use Unicode encoding for being able to use in xkb keymaps.
+        let keynames = (0..258).map(|num| format!("U{:04X}", 0x1000 + num));
+        let keycodes = generate_keycodes(keynames);
+        
+        // test now
+        let code = keycodes.get("U1101").expect("Did not find the tested keysym");
+        assert_eq!(code.keymap_idx, 1);
+    }
 }

src/layout.h

@@ -39,7 +39,6 @@ struct transformation squeek_layout_calculate_transformation(
         double allocation_width, double allocation_size);
 
 struct squeek_layout *squeek_load_layout(const char *name, uint32_t type);
-const char *squeek_layout_get_keymap(const struct squeek_layout*);
 enum squeek_arrangement_kind squeek_layout_get_kind(const struct squeek_layout *);
 void squeek_layout_free(struct squeek_layout*);
 

src/layout.rs

@@ -236,13 +236,6 @@ pub mod c {
             height: allocation_height,
         })
     }
-    
-    #[no_mangle]
-    pub extern "C"
-    fn squeek_layout_get_keymap(layout: *const Layout) -> *const c_char {
-        let layout = unsafe { &*layout };
-        layout.keymap_str.as_ptr()
-    }
 
     #[no_mangle]
     pub extern "C"
@@ -632,8 +625,8 @@ pub struct Layout {
     pub views: HashMap<String, (c::Point, View)>,
 
     // Non-UI stuff
-    /// xkb keymap applicable to the contained keys. Unchangeable
-    pub keymap_str: CString,
+    /// xkb keymaps applicable to the contained keys. Unchangeable
+    pub keymaps: Vec<CString>,
     // Changeable state
     // a Vec would be enough, but who cares, this will be small & fast enough
     // TODO: turn those into per-input point *_buttons to track dragging.
@@ -649,7 +642,7 @@ pub struct Layout {
 pub struct LayoutData {
     /// Point is the offset within layout
     pub views: HashMap<String, (c::Point, View)>,
-    pub keymap_str: CString,
+    pub keymaps: Vec<CString>,
     pub margins: Margins,
 }
 
@@ -672,7 +665,7 @@ impl Layout {
             kind,
             current_view: "base".to_owned(),
             views: data.views,
-            keymap_str: data.keymap_str,
+            keymaps: data.keymaps,
             pressed_keys: HashSet::new(),
             margins: data.margins,
         }
@@ -1135,7 +1128,7 @@ mod test {
         ]);
         let layout = Layout {
             current_view: String::new(),
-            keymap_str: CString::new("").unwrap(),
+            keymaps: Vec::new(),
             kind: ArrangementKind::Base,
             pressed_keys: HashSet::new(),
             // Lots of bottom margin

src/locale_config.rs

@@ -31,22 +31,16 @@ pub enum Error {
 
 impl ::std::fmt::Display for Error {
     fn fmt(&self, out: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
-        use ::std::error::Error;
-        out.write_str(self.description())
-    }
-}
-
-impl ::std::error::Error for Error {
-    fn description(&self) -> &str {
-        match self {
+        out.write_str(match self {
             &Error::NotWellFormed => "Language tag is not well-formed.",
             // this is exception: here we do want exhaustive match so we don't publish version with
             // missing descriptions by mistake.
             &Error::__NonExhaustive => panic!("Placeholder error must not be instantiated!"),
-        }
+        })
     }
 }
 
+
 /// Convenience Result alias.
 type Result<T> = ::std::result::Result<T, Error>;
 

src/resources.rs

@@ -17,6 +17,7 @@ const KEYBOARDS: &[(*const str, *const str)] = &[
     ("us_wide", include_str!("../data/keyboards/us_wide.yaml")),
     ("br", include_str!("../data/keyboards/br.yaml")),
     ("de", include_str!("../data/keyboards/de.yaml")),
+    ("be", include_str!("../data/keyboards/be.yaml")),
     ("de_wide", include_str!("../data/keyboards/de_wide.yaml")),
     ("dk", include_str!("../data/keyboards/dk.yaml")),
     ("es", include_str!("../data/keyboards/es.yaml")),

src/server-context-service.c

@@ -31,6 +31,7 @@
 enum {
     PROP_0,
     PROP_VISIBLE,
+    PROP_ENABLED,
     PROP_LAST
 };
 
@@ -44,6 +45,7 @@ struct _ServerContextService {
     struct ui_manager *manager; // unowned
 
     gboolean visible;
+    gboolean enabled;
     PhoshLayerSurface *window;
     GtkWidget *widget; // nullable
     guint hiding;
@@ -208,6 +210,9 @@ on_hide (ServerContextService *self)
 static void
 server_context_service_real_show_keyboard (ServerContextService *self)
 {
+    if (!self->enabled)
+        return;
+
     if (self->hiding) {
 	    g_source_remove (self->hiding);
 	    self->hiding = 0;
@@ -263,7 +268,9 @@ server_context_service_set_property (GObject      *object,
     case PROP_VISIBLE:
         self->visible = g_value_get_boolean (value);
         break;
-
+    case PROP_ENABLED:
+        server_context_service_set_enabled (self, g_value_get_boolean (value));
+        break;
     default:
         G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
         break;
@@ -319,11 +326,43 @@ server_context_service_class_init (ServerContextServiceClass *klass)
     g_object_class_install_property (gobject_class,
                                      PROP_VISIBLE,
                                      pspec);
+
+    /**
+     * ServerContextServie:keyboard:
+     *
+     * Does the user want the keyboard to show up automatically?
+     */
+    pspec =
+        g_param_spec_boolean ("enabled",
+                              "Enabled",
+                              "Whether the keyboard is enabled",
+                              TRUE,
+                              G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
+    g_object_class_install_property (gobject_class,
+                                     PROP_ENABLED,
+                                     pspec);
 }
 
 static void
 server_context_service_init (ServerContextService *self) {
-    (void)self;
+    const char *schema_name = "org.gnome.desktop.a11y.applications";
+    GSettingsSchemaSource *ssrc = g_settings_schema_source_get_default();
+    g_autoptr(GSettingsSchema) schema = NULL;
+
+    self->enabled = TRUE;
+    if (!ssrc) {
+        g_warning("No gsettings schemas installed.");
+        return;
+    }
+    schema = g_settings_schema_source_lookup(ssrc, schema_name, TRUE);
+    if (schema) {
+        g_autoptr(GSettings) settings = g_settings_new (schema_name);
+        g_settings_bind (settings, "screen-keyboard-enabled",
+                         self, "enabled", G_SETTINGS_BIND_GET);
+    } else {
+        g_warning("Gsettings schema %s is not installed on the system. "
+                  "Enabling by default.", schema_name);
+    }
 }
 
 ServerContextService *
@@ -336,3 +375,18 @@ server_context_service_new (EekboardContextService *self, struct submission *sub
     ui->manager = uiman;
     return ui;
 }
+
+void
+server_context_service_set_enabled (ServerContextService *self, gboolean enabled)
+{
+    g_return_if_fail (SERVER_IS_CONTEXT_SERVICE (self));
+
+    if (enabled == self->enabled)
+        return;
+
+    self->enabled = enabled;
+    if (self->enabled)
+        server_context_service_show_keyboard (self);
+    else
+        server_context_service_hide_keyboard (self);
+}

src/server-context-service.h

@@ -33,6 +33,7 @@ ServerContextService *server_context_service_new(EekboardContextService *self, s
 enum squeek_arrangement_kind server_context_service_get_layout_type(ServerContextService *);
 void server_context_service_show_keyboard (ServerContextService *self);
 void server_context_service_hide_keyboard (ServerContextService *self);
+void server_context_service_set_enabled (ServerContextService *self, gboolean enabled);
 G_END_DECLS
 #endif  /* SERVER_CONTEXT_SERVICE_H */
 

src/submission.h

@@ -6,6 +6,7 @@
 #include "eek/eek-types.h"
 
 struct submission;
+struct squeek_layout;
 
 struct submission* get_submission(struct zwp_input_method_manager_v2 *immanager,
                                   struct zwp_virtual_keyboard_manager_v1 *vkmanager,
@@ -15,5 +16,5 @@ struct submission* get_submission(struct zwp_input_method_manager_v2 *immanager,
 // Defined in Rust
 struct submission* submission_new(struct zwp_input_method_v2 *im, struct zwp_virtual_keyboard_v1 *vk, EekboardContextService *state);
 void submission_set_ui(struct submission *self, ServerContextService *ui_context);
-void submission_set_keyboard(struct submission *self, LevelKeyboard *keyboard, uint32_t time);
+void submission_use_layout(struct submission *self, struct squeek_layout *layout, uint32_t time);
 #endif

src/submission.rs

@@ -23,8 +23,9 @@ use ::action::Modifier;
 use ::imservice;
 use ::imservice::IMService;
 use ::keyboard::{ KeyCode, KeyStateId, Modifiers, PressType };
-use ::layout::c::LevelKeyboard;
+use ::layout;
 use ::util::vec_remove;
+use ::vkeyboard;
 use ::vkeyboard::VirtualKeyboard;
 
 // traits
@@ -68,6 +69,8 @@ pub mod c {
                 modifiers_active: Vec::new(),
                 virtual_keyboard: VirtualKeyboard(vk),
                 pressed: Vec::new(),
+                keymap_fds: Vec::new(),
+                keymap_idx: None,
             }
         ))
     }
@@ -91,16 +94,17 @@ pub mod c {
 
     #[no_mangle]
     pub extern "C"
-    fn submission_set_keyboard(
+    fn submission_use_layout(
         submission: *mut Submission,
-        keyboard: LevelKeyboard,
+        layout: *const layout::Layout,
         time: u32,
     ) {
         if submission.is_null() {
             panic!("Null submission pointer");
         }
         let submission: &mut Submission = unsafe { &mut *submission };
-        submission.update_keymap(keyboard, Timestamp(time));
+        let layout = unsafe { &*layout };
+        submission.use_layout(layout, Timestamp(time));
     }
 }
 
@@ -119,6 +123,8 @@ pub struct Submission {
     virtual_keyboard: VirtualKeyboard,
     modifiers_active: Vec<(KeyStateId, Modifier)>,
     pressed: Vec<(KeyStateId, SubmittedAction)>,
+    keymap_fds: Vec<vkeyboard::c::KeyMap>,
+    keymap_idx: Option<usize>,
 }
 
 pub enum SubmitData<'a> {
@@ -177,11 +183,34 @@ impl Submission {
         let submit_action = match was_committed_as_text {
             true => SubmittedAction::IMService,
             false => {
-                self.virtual_keyboard.switch(
-                    keycodes,
-                    PressType::Pressed,
-                    time,
-                );
+                let keycodes_count = keycodes.len();
+                for keycode in keycodes.iter() {
+                    self.select_keymap(keycode.keymap_idx, time);
+                    let keycode = keycode.code;
+                    match keycodes_count {
+                        // Pressing a key made out of a single keycode is simple:
+                        // press on press, release on release.
+                        1 => self.virtual_keyboard.switch(
+                            keycode,
+                            PressType::Pressed,
+                            time,
+                        ),
+                        // A key made of multiple keycodes
+                        // has to submit them one after the other.
+                        _ => {
+                            self.virtual_keyboard.switch(
+                                keycode.clone(),
+                                PressType::Pressed,
+                                time,
+                            );
+                            self.virtual_keyboard.switch(
+                                keycode.clone(),
+                                PressType::Released,
+                                time,
+                            );
+                        },
+                    };
+                }
                 SubmittedAction::VirtualKeyboard(keycodes.clone())
             },
         };
@@ -199,11 +228,21 @@ impl Submission {
                 // no matter if the imservice got activated,
                 // keys must be released
                 SubmittedAction::VirtualKeyboard(keycodes) => {
-                    self.virtual_keyboard.switch(
-                        &keycodes,
-                        PressType::Released,
-                        time,
-                    )
+                    let keycodes_count = keycodes.len();
+                    match keycodes_count {
+                        1 => {
+                            let keycode = &keycodes[0];
+                            self.select_keymap(keycode.keymap_idx, time);
+                            self.virtual_keyboard.switch(
+                                keycode.code,
+                                PressType::Released,
+                                time,
+                            );
+                        },
+                        // Design choice here: submit multiple all at press time
+                        // and do nothing at release time.
+                        _ => {},
+                    };
                 },
             }
         };
@@ -274,6 +313,7 @@ impl Submission {
         }
     }
 
+
     /// Changes keymap and clears pressed keys and modifiers.
     ///
     /// It's not obvious if clearing is the right thing to do, 
@@ -283,9 +323,28 @@ impl Submission {
     /// Alternatively, modifiers could be restored on the new keymap.
     /// That approach might be difficult
     /// due to modifiers meaning different things in different keymaps.
-    pub fn update_keymap(&mut self, keyboard: LevelKeyboard, time: Timestamp) {
-        self.clear_all_modifiers();
-        self.release_all_virtual_keys(time);
-        self.virtual_keyboard.update_keymap(keyboard);
+    fn select_keymap(&mut self, idx: usize, time: Timestamp) {
+        if self.keymap_idx != Some(idx) {
+            self.keymap_idx = Some(idx);
+            self.clear_all_modifiers();
+            self.release_all_virtual_keys(time);
+            let keymap = &self.keymap_fds[idx];
+            self.virtual_keyboard.update_keymap(keymap);
+        }
+    }
+    
+    pub fn use_layout(&mut self, layout: &layout::Layout, time: Timestamp) {
+        self.keymap_fds = layout.keymaps.iter()
+            .map(|keymap_str| vkeyboard::c::KeyMap::from_cstr(
+                keymap_str.as_c_str()
+            ))
+            .collect();
+        self.keymap_idx = None;
+
+        // This can probably be eliminated,
+        // because key presses can trigger an update anyway.
+        // However, self.keymap_idx needs to become Option<>
+        // in order to force update on new layouts.
+        self.select_keymap(0, time);
     }
 }

src/tests.rs

@@ -26,49 +26,104 @@ impl CountAndPrint {
     }
 }
 
-pub fn check_builtin_layout(name: &str) {
-    check_layout(Layout::from_resource(name).expect("Invalid layout data"))
+pub fn check_builtin_layout(name: &str, missing_return: bool) {
+    check_layout(
+        Layout::from_resource(name).expect("Invalid layout data"),
+        missing_return,
+    )
 }
 
 pub fn check_layout_file(path: &str) {
-    check_layout(Layout::from_file(path.into()).expect("Invalid layout file"))
+    check_layout(
+        Layout::from_file(path.into()).expect("Invalid layout file"),
+        false,
+    )
 }
 
-fn check_layout(layout: Layout) {
+fn check_sym_in_keymap(state: &xkb::State, sym_name: &str) -> bool {
+    let sym = xkb::keysym_from_name(sym_name, xkb::KEYSYM_NO_FLAGS);
+    if sym == xkb::KEY_NoSymbol {
+        panic!(format!("Entered invalid keysym: {}", sym_name));
+    }
+    let map = state.get_keymap();
+    let range = map.min_keycode()..=map.max_keycode();
+    range.flat_map(|code| state.key_get_syms(code))
+        .find(|s| **s == sym)
+        .is_some()
+}
+
+fn check_sym_presence(
+    states: &[xkb::State],
+    sym_name: &str,
+    handler: &mut dyn logging::Handler,
+) {
+    let found = states.iter()
+        .position(|state| {
+            check_sym_in_keymap(&state, sym_name)
+        });
+
+    if let None = found {
+        handler.handle(
+            logging::Level::Surprise,
+            &format!("There's no way to input the keysym {} on this layout", sym_name),
+        )
+    }
+}
+
+fn check_layout(layout: Layout, allow_missing_return: bool) {
     let handler = CountAndPrint::new();
-    let (layout, handler) = layout.build(handler);
+    let (layout, mut handler) = layout.build(handler);
 
     if handler.0 > 0 {
         println!("{} problems while parsing layout", handler.0)
     }
 
     let layout = layout.expect("layout broken");
+    
+    let xkb_states: Vec<xkb::State> = layout.keymaps.iter()
+        .map(|keymap_str| {
+            let context = xkb::Context::new(xkb::CONTEXT_NO_FLAGS);
+            let keymap_str = keymap_str
+                .clone()
+                .into_string().expect("Failed to decode keymap string");
+            let keymap = xkb::Keymap::new_from_string(
+                &context,
+                keymap_str.clone(),
+                xkb::KEYMAP_FORMAT_TEXT_V1,
+                xkb::KEYMAP_COMPILE_NO_FLAGS,
+            ).expect("Failed to create keymap");
+            xkb::State::new(&keymap)
+        })
+        .collect();
 
-    let context = xkb::Context::new(xkb::CONTEXT_NO_FLAGS);
-    
-    let keymap_str = layout.keymap_str
-        .clone()
-        .into_string().expect("Failed to decode keymap string");
-    
-    let keymap = xkb::Keymap::new_from_string(
-        &context,
-        keymap_str.clone(),
-        xkb::KEYMAP_FORMAT_TEXT_V1,
-        xkb::KEYMAP_COMPILE_NO_FLAGS,
-    ).expect("Failed to create keymap");
+    check_sym_presence(&xkb_states, "BackSpace", &mut handler);
+    let mut printer = logging::Print;
+    check_sym_presence(
+        &xkb_states,
+        "Return",
+        if allow_missing_return { &mut printer }
+        else { &mut handler },
+    );
 
-    let state = xkb::State::new(&keymap);
-    
     // "Press" each button with keysyms
     for (_pos, view) in layout.views.values() {
         for (_y, row) in &view.get_rows() {
             for (_x, button) in &row.buttons {
                 let keystate = button.state.borrow();
                 for keycode in &keystate.keycodes {
-                    match state.key_get_one_sym(*keycode) {
+                    match xkb_states[keycode.keymap_idx].key_get_one_sym(keycode.code) {
                         xkb::KEY_NoSymbol => {
-                            eprintln!("{}", keymap_str);
-                            panic!("Keysym {} on key {:?} can't be resolved", keycode, button.name);
+                            eprintln!(
+                                "keymap {}: {}",
+                                keycode.keymap_idx,
+                                layout.keymaps[keycode.keymap_idx].to_str().unwrap(),
+                            );
+                            panic!(
+                                "Keysym for code {:?} on key {} ({:?}) can't be resolved",
+                                keycode,
+                                button.name.to_string_lossy(),
+                                button.name,
+                            );
                         },
                         _ => {},
                     }

src/util.rs

@@ -203,6 +203,23 @@ pub fn vec_remove<T, F: FnMut(&T) -> bool>(v: &mut Vec<T>, pred: F) -> Option<T>
     idx.map(|idx| v.remove(idx))
 }
 
+/// Repeats all the items of the iterator forever,
+/// but returns the cycle number alongside.
+/// Inefficient due to all the vectors, but doesn't have to be fast.
+pub fn cycle_count<T, I: Clone + Iterator<Item=T>>(iter: I)
+    -> impl Iterator<Item=(T, usize)>
+{
+    let numbered_copies = vec![iter].into_iter()
+        .cycle()
+        .enumerate();
+    numbered_copies.flat_map(|(idx, cycle)|
+        // Pair each element from the cycle with a copy of the index.
+        cycle.zip(
+            vec![idx].into_iter().cycle() // Repeat the index forever.
+        )
+    )
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -217,4 +234,12 @@ mod tests {
         assert_eq!(s.insert(Pointer(Rc::new(2u32))), true);
         assert_eq!(s.remove(&Pointer(first)), true);
     }
+
+    #[test]
+    fn check_count() {
+        assert_eq!(
+            cycle_count(5..8).take(7).collect::<Vec<_>>(),
+            vec![(5, 0), (6, 0), (7, 0), (5, 1), (6, 1), (7, 1), (5, 2)]
+        );
+    }
 }

src/vkeyboard.rs

@@ -1,18 +1,42 @@
 /*! Managing the events belonging to virtual-keyboard interface. */
 
-use ::keyboard::{ KeyCode, Modifiers, PressType };
-use ::layout::c::LevelKeyboard;
+use ::keyboard::{ Modifiers, PressType };
 use ::submission::Timestamp;
 
+/// Standard xkb keycode
+type KeyCode = u32;
+
 /// Gathers stuff defined in C or called by C
 pub mod c {
-    use super::*;
-    use std::os::raw::c_void;
+    use std::ffi::CStr;
+    use std::os::raw::{ c_char, c_void };
 
     #[repr(transparent)]
     #[derive(Clone, Copy)]
     pub struct ZwpVirtualKeyboardV1(*const c_void);
 
+    #[repr(C)]
+    pub struct KeyMap {
+        fd: u32,
+        fd_len: usize,
+    }
+    
+    impl KeyMap {
+        pub fn from_cstr(s: &CStr) -> KeyMap {
+            unsafe {
+                eek_key_map_from_str(s.as_ptr())
+            }
+        }
+    }
+
+    impl Drop for KeyMap {
+        fn drop(&mut self) {
+            unsafe {
+                eek_key_map_deinit(self as *mut KeyMap);
+            }
+        }
+    }
+
     #[no_mangle]
     extern "C" {
         pub fn eek_virtual_keyboard_v1_key(
@@ -24,13 +48,16 @@ pub mod c {
 
         pub fn eek_virtual_keyboard_update_keymap(
             virtual_keyboard: ZwpVirtualKeyboardV1,
-            keyboard: LevelKeyboard,
+            keymap: *const KeyMap,
         );
         
         pub fn eek_virtual_keyboard_set_modifiers(
             virtual_keyboard: ZwpVirtualKeyboardV1,
             modifiers: u32,
         );
+        
+        pub fn eek_key_map_from_str(keymap_str: *const c_char) -> KeyMap;
+        pub fn eek_key_map_deinit(keymap: *mut KeyMap);
     }
 }
 
@@ -41,35 +68,15 @@ impl VirtualKeyboard {
     // TODO: error out if keymap not set
     pub fn switch(
         &self,
-        keycodes: &Vec<KeyCode>,
+        keycode: KeyCode,
         action: PressType,
         timestamp: Timestamp,
     ) {
-        let keycodes_count = keycodes.len();
-        for keycode in keycodes.iter() {
-            let keycode = keycode - 8;
-            match (action, keycodes_count) {
-                // Pressing a key made out of a single keycode is simple:
-                // press on press, release on release.
-                (_, 1) => unsafe {
-                    c::eek_virtual_keyboard_v1_key(
-                        self.0, timestamp.0, keycode, action.clone() as u32
-                    );
-                },
-                // A key made of multiple keycodes
-                // has to submit them one after the other
-                (PressType::Pressed, _) => unsafe {
-                    c::eek_virtual_keyboard_v1_key(
-                        self.0, timestamp.0, keycode, PressType::Pressed as u32
-                    );
-                    c::eek_virtual_keyboard_v1_key(
-                        self.0, timestamp.0, keycode, PressType::Released as u32
-                    );
-                },
-                // Design choice here: submit multiple all at press time
-                // and do nothing at release time
-                (PressType::Released, _) => {},
-            }
+        let keycode = keycode - 8;
+        unsafe {
+            c::eek_virtual_keyboard_v1_key(
+                self.0, timestamp.0, keycode, action.clone() as u32
+            );
         }
     }
     
@@ -80,9 +87,12 @@ impl VirtualKeyboard {
         }
     }
     
-    pub fn update_keymap(&self, keyboard: LevelKeyboard) {
+    pub fn update_keymap(&self, keymap: &c::KeyMap) {
         unsafe {
-            c::eek_virtual_keyboard_update_keymap(self.0, keyboard);
+            c::eek_virtual_keyboard_update_keymap(
+                self.0,
+                keymap as *const c::KeyMap,
+            );
         }
     }
 }

src/wayland.c

@@ -14,10 +14,10 @@ eek_virtual_keyboard_v1_key(struct zwp_virtual_keyboard_v1 *zwp_virtual_keyboard
 }
 
 
-void eek_virtual_keyboard_update_keymap(struct zwp_virtual_keyboard_v1 *zwp_virtual_keyboard_v1, const LevelKeyboard *keyboard) {
+void eek_virtual_keyboard_update_keymap(struct zwp_virtual_keyboard_v1 *zwp_virtual_keyboard_v1, struct KeyMap *keymap) {
     zwp_virtual_keyboard_v1_keymap(zwp_virtual_keyboard_v1,
         WL_KEYBOARD_KEYMAP_FORMAT_XKB_V1,
-        keyboard->keymap_fd, keyboard->keymap_len);
+        keymap->fd, keymap->fd_len);
 }
 
 void

tests/layout_erase.yaml

@@ -0,0 +1,10 @@
+---
+# Erase only
+views:
+    base:
+        - "BackSpace"
+outlines:
+    default: { width: 0, height: 0 }
+buttons:
+    BackSpace:
+        action: erase

tests/meson.build

@@ -50,6 +50,7 @@ endforeach
 foreach layout : [
     'us', 'us_wide',
     'br',
+    'be',
     'de', 'de_wide',
     'dk',
     'es',
@@ -68,11 +69,17 @@ foreach layout : [
     
     'emoji',
 ]
+    extra = []
+    if layout == 'emoji'
+        extra += ['allow_missing_return']
+    endif
+
     test(
         'test_layout_' + layout,
         cargo_script,
         args: ['run'] + cargo_build_flags
-            + [ '--example', 'test_layout', '--', layout],
+            + ['--example', 'test_layout', '--', layout]
+            + extra,
         workdir: meson.build_root(),
     )
 endforeach