Merge branch 'wayland-output-grab-input' into 'master'

Add the ability for wayland output to grab input

See merge request wlroots/wlroots!4441

backend/backend.c

@@ -4,6 +4,8 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <strings.h>
+#include <xkbcommon/xkbcommon.h>
 #include <wayland-server-core.h>
 
 #include <wlr/backend/headless.h>
@@ -13,6 +15,7 @@
 #include <wlr/config.h>
 #include <wlr/render/wlr_renderer.h>
 #include <wlr/util/log.h>
+#include <wlr/types/wlr_keyboard.h>
 #include "backend/backend.h"
 #include "backend/multi.h"
 #include "render/allocator/allocator.h"
@@ -146,6 +149,37 @@ static size_t parse_outputs_env(const char *name) {
 	return outputs;
 }
 
+// This code was copied from sway wm source code,
+// from https://github.com/swaywm/sway/blob/7cf4e1d/sway/input/keyboard.c
+// ____________________________________________________
+static struct modifier_key {
+	char *name;
+	uint32_t mod;
+} modifiers[] = {
+	{ XKB_MOD_NAME_SHIFT, WLR_MODIFIER_SHIFT },
+	{ XKB_MOD_NAME_CAPS , WLR_MODIFIER_CAPS  },
+	{ XKB_MOD_NAME_CTRL , WLR_MODIFIER_CTRL  },
+	{ "Ctrl"            , WLR_MODIFIER_CTRL  },
+	{ XKB_MOD_NAME_ALT  , WLR_MODIFIER_ALT   },
+	{ "Alt"             , WLR_MODIFIER_ALT   },
+	{ XKB_MOD_NAME_NUM  , WLR_MODIFIER_MOD2  },
+	{ "Mod3"            , WLR_MODIFIER_MOD3  },
+	{ XKB_MOD_NAME_LOGO , WLR_MODIFIER_LOGO  },
+	{ "Mod5"            , WLR_MODIFIER_MOD5  },
+};
+
+static uint32_t get_modifier_mask_by_name(const char *name) {
+	int i;
+	for (i = 0; i < (int)(sizeof(modifiers) / sizeof(struct modifier_key)); ++i) {
+		if (strcasecmp(modifiers[i].name, name) == 0) {
+			return modifiers[i].mod;
+		}
+	}
+
+	return 0;
+}
+// ____________________________________________________)
+
 static struct wlr_backend *attempt_wl_backend(struct wl_display *display) {
 	struct wlr_backend *backend = wlr_wl_backend_create(display, NULL);
 	if (backend == NULL) {
@@ -157,6 +191,37 @@ static struct wlr_backend *attempt_wl_backend(struct wl_display *display) {
 		wlr_wl_output_create(backend);
 	}
 
+	char* keyboard_shortcut = getenv("WLR_WL_GRAB_INPUT_SHORTCUT");
+	if (keyboard_shortcut) {
+		wlr_log(WLR_INFO, "Loading user-specified input grab keyboard shortcut: %s",
+			keyboard_shortcut);
+		xkb_keysym_t input_grab_keysym = 0;
+		uint32_t input_grab_modifier_mask = 0;
+		keyboard_shortcut = strdup(keyboard_shortcut);
+
+		char *saveptr;
+		char *key_name = strtok_r(keyboard_shortcut, "+", &saveptr);
+		while (key_name  != NULL) {
+
+			uint32_t modifier_mask = get_modifier_mask_by_name(key_name);
+			input_grab_modifier_mask = input_grab_modifier_mask | modifier_mask;
+			if(modifier_mask == 0) {
+				input_grab_keysym = xkb_keysym_from_name(key_name,XKB_KEYSYM_CASE_INSENSITIVE);
+				if(input_grab_keysym == 0) {
+					wlr_log(WLR_ERROR,
+							"The key shortcut contains an unrecognized key name. ignoring key shortcut");
+					input_grab_keysym = 0;
+					input_grab_modifier_mask = 0;
+					free(keyboard_shortcut);
+					return backend;
+				}
+			}
+			key_name  = strtok_r(NULL, "+", &saveptr);
+		}
+	free(keyboard_shortcut);
+	wlr_wl_backend_set_grab_input_shortcut(backend, input_grab_modifier_mask, input_grab_keysym);
+	}
+
 	return backend;
 }
 

backend/wayland/backend.c

@@ -30,6 +30,8 @@
 #include "tablet-unstable-v2-client-protocol.h"
 #include "relative-pointer-unstable-v1-client-protocol.h"
 #include "viewporter-client-protocol.h"
+#include "pointer-constraints-unstable-v1-client-protocol.h"
+#include "keyboard-shortcuts-inhibit-unstable-v1-client-protocol.h"
 
 struct wlr_wl_linux_dmabuf_feedback_v1 {
 	struct wlr_wl_backend *backend;
@@ -405,6 +407,12 @@ static void registry_global(void *data, struct wl_registry *registry,
 	} else if (strcmp(iface, wp_viewporter_interface.name) == 0) {
 		wl->viewporter = wl_registry_bind(registry, name,
 			&wp_viewporter_interface, 1);
+	} else if (strcmp(iface,zwp_pointer_constraints_v1_interface.name)==0) {
+		wl->pointer_constraints = wl_registry_bind(registry, name,
+			&zwp_pointer_constraints_v1_interface, 1);
+	} else if(strcmp(iface,zwp_keyboard_shortcuts_inhibit_manager_v1_interface.name)==0) {
+		wl->shortcuts_inhibit_manager = wl_registry_bind(registry, name,
+			&zwp_keyboard_shortcuts_inhibit_manager_v1_interface, 1);
 	}
 }
 
@@ -506,6 +514,12 @@ static void backend_destroy(struct wlr_backend *backend) {
 	if (wl->tablet_manager) {
 		zwp_tablet_manager_v2_destroy(wl->tablet_manager);
 	}
+	if(wl->pointer_constraints) {
+		zwp_pointer_constraints_v1_destroy (wl->pointer_constraints);
+	}
+	if(wl->shortcuts_inhibit_manager) {
+		zwp_keyboard_shortcuts_inhibit_manager_v1_destroy (wl->shortcuts_inhibit_manager);
+	}
 	if (wl->presentation) {
 		wp_presentation_destroy(wl->presentation);
 	}
@@ -702,3 +716,10 @@ struct wl_display *wlr_wl_backend_get_remote_display(struct wlr_backend *backend
 	struct wlr_wl_backend *wl = get_wl_backend_from_backend(backend);
 	return wl->remote_display;
 }
+
+void wlr_wl_backend_set_grab_input_shortcut(struct wlr_backend *backend, uint32_t modifiers_mask,
+		xkb_keysym_t keysym) {
+	struct wlr_wl_backend *wl = get_wl_backend_from_backend(backend);
+	wl->input_grab_modifiers_mask = modifiers_mask;
+	wl->input_grab_keysym = keysym;
+}

backend/wayland/meson.build

@@ -23,6 +23,8 @@ client_protos = [
 	'xdg-activation-v1',
 	'xdg-decoration-unstable-v1',
 	'xdg-shell',
+	'pointer-constraints-unstable-v1',
+	'keyboard-shortcuts-inhibit-unstable-v1',
 ]
 
 foreach proto : client_protos

backend/wayland/seat.c

@@ -6,6 +6,7 @@
 #include <string.h>
 #include <time.h>
 #include <unistd.h>
+#include <xkbcommon/xkbcommon.h>
 
 #include <wayland-client.h>
 
@@ -19,6 +20,151 @@
 
 #include "backend/wayland.h"
 #include "util/time.h"
+#include "keyboard-shortcuts-inhibit-unstable-v1-client-protocol.h"
+#include "pointer-constraints-unstable-v1-client-protocol.h"
+
+//these functions are based on functions with simillar names from xwayland code
+// (https://gitlab.freedesktop.org/xorg/xserver/-/blob/befef003/hw/xwayland/xwayland-input.c)
+// ______________________________________________________________________
+static void wlr_wl_seat_destroy_confined_pointer(struct wlr_wl_seat *seat) {
+	if(seat->confined_pointer != NULL) {
+		zwp_confined_pointer_v1_destroy(seat->confined_pointer);
+		seat->confined_pointer = NULL;
+	}
+
+}
+
+static void wlr_wl_seat_unconfine_pointer(struct wlr_wl_seat *seat) {
+
+	if (seat->confined_pointer) {
+		wlr_wl_seat_destroy_confined_pointer(seat);
+	}
+}
+
+static void wlr_wl_seat_confine_pointer(struct wlr_wl_seat *seat) {
+	struct zwp_pointer_constraints_v1 *pointer_constraints =
+		seat->backend->pointer_constraints;
+
+	if (!pointer_constraints) {
+		return;
+	}
+
+
+	if (!seat->wl_pointer) {
+		return;
+	}
+
+	if (seat->confined_pointer) {
+		return;
+	}
+
+
+	wlr_wl_seat_unconfine_pointer(seat);
+
+	struct wl_surface *surface = seat->grab_surface;
+		  if(surface == NULL) {
+		  wlr_log (WLR_INFO, "surface is null!!!");
+		  return;
+		}
+	seat->confined_pointer =
+		zwp_pointer_constraints_v1_confine_pointer(pointer_constraints,
+												   surface,
+												   seat->wl_pointer,
+												   NULL,
+												   ZWP_POINTER_CONSTRAINTS_V1_LIFETIME_PERSISTENT);
+}
+
+
+static void maybe_fake_grab_devices(struct wlr_wl_seat *seat) {
+	wlr_log (WLR_INFO,"Grabbed seat '%s' input!!!!", seat->name);
+	struct wlr_wl_backend *backend = seat->backend;
+
+	wlr_wl_seat_confine_pointer(seat);
+	if (!backend->shortcuts_inhibit_manager) {
+		  return;
+	}
+
+	if (backend->shortcuts_inhibit) {
+		  return;
+	}
+	struct wl_surface *surface =  seat->grab_surface;
+	if(surface == NULL) {
+		wlr_log (WLR_INFO, "surface is null!!!");
+		return;
+	}
+	backend->shortcuts_inhibit =
+		zwp_keyboard_shortcuts_inhibit_manager_v1_inhibit_shortcuts (
+			backend->shortcuts_inhibit_manager,
+			surface,
+			seat->wl_seat);
+}
+
+static void maybe_fake_ungrab_devices(struct wlr_wl_seat *seat)
+{
+	wlr_log (WLR_INFO,"Released seat '%s' input!!!!", seat->name);
+	struct wlr_wl_backend *backend = seat->backend;
+
+	wlr_wl_seat_unconfine_pointer(seat);
+
+	if (!backend->shortcuts_inhibit) {
+		return;
+	}
+	zwp_keyboard_shortcuts_inhibitor_v1_destroy (backend->shortcuts_inhibit);
+	backend->shortcuts_inhibit = NULL;
+}
+// ______________________________________________________________________
+static bool fake_grab_input_shortcut_was_pressed(xkb_keysym_t keysym, uint32_t depressed_modifiers,
+		xkb_keysym_t input_grab_keysym, uint32_t input_grab_modifiers_mask) {
+
+	xkb_keysym_t input_grab_keysym_lowercase = xkb_keysym_to_lower(input_grab_keysym);
+	xkb_keysym_t keysym_lowercase = xkb_keysym_to_lower(keysym);
+
+	if(!input_grab_keysym && !input_grab_modifiers_mask) {
+		return false;
+	}
+
+	bool input_grab_only_modifiers = (input_grab_modifiers_mask == depressed_modifiers)
+			&& !input_grab_keysym;
+	bool input_grab_only_keysym = !input_grab_modifiers_mask
+			&& (input_grab_keysym_lowercase == keysym_lowercase);
+	bool input_grab_modifiers_and_keysym= (input_grab_modifiers_mask == depressed_modifiers)
+			&& (input_grab_keysym_lowercase==keysym_lowercase);
+
+	return input_grab_only_modifiers || input_grab_only_keysym || input_grab_modifiers_and_keysym;
+}
+
+static void maybe_toggle_fake_grab(struct wlr_wl_seat *seat, uint32_t key, uint32_t state) {
+	if(seat->grab_surface == NULL) {
+		wlr_log (WLR_INFO, "input surface is null. not grabbing/releasing!");
+		return;
+	}
+
+	struct wlr_keyboard *keyboard = &seat->wlr_keyboard;
+	struct xkb_state *xkb_state = keyboard->xkb_state;
+
+	xkb_keysym_t input_grab_keysym = seat->backend->input_grab_keysym;
+	uint32_t input_grab_modifiers_mask = seat->backend->input_grab_modifiers_mask;
+	uint32_t depressed_modifiers = keyboard->modifiers.depressed;
+
+	xkb_keysym_t keysym = xkb_state_key_get_one_sym(xkb_state, key + 8);
+
+	if(state != WL_KEYBOARD_KEY_STATE_RELEASED) {
+		  return;
+	}
+
+	if(fake_grab_input_shortcut_was_pressed(keysym, depressed_modifiers, input_grab_keysym,
+			input_grab_modifiers_mask)) {
+		seat->has_grab = !seat->has_grab;
+
+		if (seat->has_grab) {
+			maybe_fake_grab_devices(seat);
+		}
+
+		else {
+			maybe_fake_ungrab_devices(seat);
+		}
+	}
+}
 
 static void keyboard_handle_keymap(void *data, struct wl_keyboard *wl_keyboard,
 		uint32_t format, int32_t fd, uint32_t size) {
@@ -27,8 +173,10 @@ static void keyboard_handle_keymap(void *data, struct wl_keyboard *wl_keyboard,
 
 static void keyboard_handle_enter(void *data, struct wl_keyboard *wl_keyboard,
 		uint32_t serial, struct wl_surface *surface, struct wl_array *keys) {
-	struct wlr_keyboard *keyboard = data;
+	struct wlr_wl_seat *seat = data;
+	struct wlr_keyboard *keyboard = &seat->wlr_keyboard;
 
+	seat->grab_surface = surface;
 	uint32_t *keycode_ptr;
 	wl_array_for_each(keycode_ptr, keys) {
 		struct wlr_keyboard_key_event event = {
@@ -43,8 +191,10 @@ static void keyboard_handle_enter(void *data, struct wl_keyboard *wl_keyboard,
 
 static void keyboard_handle_leave(void *data, struct wl_keyboard *wl_keyboard,
 		uint32_t serial, struct wl_surface *surface) {
-	struct wlr_keyboard *keyboard = data;
+	struct wlr_wl_seat *seat = data;
+	struct wlr_keyboard *keyboard = &seat->wlr_keyboard;
 
+	seat->grab_surface = NULL;
 	size_t num_keycodes = keyboard->num_keycodes;
 	uint32_t pressed[num_keycodes + 1];
 	memcpy(pressed, keyboard->keycodes,
@@ -65,7 +215,8 @@ static void keyboard_handle_leave(void *data, struct wl_keyboard *wl_keyboard,
 
 static void keyboard_handle_key(void *data, struct wl_keyboard *wl_keyboard,
 		uint32_t serial, uint32_t time, uint32_t key, uint32_t state) {
-	struct wlr_keyboard *keyboard = data;
+	struct wlr_wl_seat *seat = data;
+	struct wlr_keyboard *keyboard = &seat->wlr_keyboard;
 
 	struct wlr_keyboard_key_event wlr_event = {
 		.keycode = key,
@@ -74,12 +225,14 @@ static void keyboard_handle_key(void *data, struct wl_keyboard *wl_keyboard,
 		.update_state = false,
 	};
 	wlr_keyboard_notify_key(keyboard, &wlr_event);
+	maybe_toggle_fake_grab (seat,key,state);
 }
 
 static void keyboard_handle_modifiers(void *data, struct wl_keyboard *wl_keyboard,
 		uint32_t serial, uint32_t mods_depressed, uint32_t mods_latched,
 		uint32_t mods_locked, uint32_t group) {
-	struct wlr_keyboard *keyboard = data;
+	struct wlr_wl_seat *seat = data;
+	struct wlr_keyboard *keyboard = &seat->wlr_keyboard;
 	wlr_keyboard_notify_modifiers(keyboard, mods_depressed, mods_latched,
 		mods_locked, group);
 }
@@ -109,8 +262,9 @@ void init_seat_keyboard(struct wlr_wl_seat *seat) {
 	snprintf(name, sizeof(name), "wayland-keyboard-%s", seat->name);
 
 	wlr_keyboard_init(&seat->wlr_keyboard, &keyboard_impl, name);
+	//passing wlr_wl_seat instead of wlr_keyboard to enable the fake input grab functionality
 	wl_keyboard_add_listener(seat->wl_keyboard, &keyboard_listener,
-		&seat->wlr_keyboard);
+		seat);
 
 	wl_signal_emit_mutable(&seat->backend->backend.events.new_input,
 		&seat->wlr_keyboard.base);

docs/env_vars.md

@@ -39,6 +39,7 @@ wlroots reads these environment variables
 ## Wayland backend
 
 * *WLR_WL_OUTPUTS*: when using the wayland backend specifies the number of outputs
+* *WLR_WL_GRAB_INPUT_SHORTCUT*: when using the wayland backend, specify the shortcut (mods+key) to toggle input grab of the focused wayland output. Examples: control+shift+alt, control_r, alt_l.
 
 ## X11 backend
 

include/backend/wayland.h

@@ -18,6 +18,8 @@
 struct wlr_wl_backend {
 	struct wlr_backend backend;
 
+	uint32_t input_grab_modifiers_mask; //for input grab.
+	xkb_keysym_t input_grab_keysym; //for input grab.
 	/* local state */
 	bool started;
 	struct wl_display *local_display;
@@ -49,6 +51,9 @@ struct wlr_wl_backend {
 	struct xdg_activation_v1 *activation_v1;
 	struct wl_subcompositor *subcompositor;
 	struct wp_viewporter *viewporter;
+	struct zwp_pointer_constraints_v1 *pointer_constraints;
+	struct zwp_keyboard_shortcuts_inhibit_manager_v1 *shortcuts_inhibit_manager;
+	struct zwp_keyboard_shortcuts_inhibitor_v1 *shortcuts_inhibit;
 	char *drm_render_name;
 };
 
@@ -135,6 +140,7 @@ struct wlr_wl_seat {
 	struct wlr_wl_pointer *active_pointer;
 	struct wl_list pointers; // wlr_wl_pointer.link
 
+	struct wl_surface *grab_surface; //for fake grabbing input. may be NULL when keyboard focus is not on any wayland output
 	struct zwp_pointer_gesture_swipe_v1 *gesture_swipe;
 	struct zwp_pointer_gesture_pinch_v1 *gesture_pinch;
 	struct zwp_pointer_gesture_hold_v1 *gesture_hold;
@@ -151,6 +157,8 @@ struct wlr_wl_seat {
 	struct wlr_tablet_tool wlr_tablet_tool;
 	struct zwp_tablet_pad_v2 *zwp_tablet_pad_v2;
 	struct wlr_tablet_pad wlr_tablet_pad;
+	struct zwp_confined_pointer_v1 *confined_pointer;
+	bool has_grab; //for fake grabbing input. may be NULL when no grab was initiated yet.
 
 	struct wl_list link; // wlr_wl_backend.seats
 };

include/wlr/backend/wayland.h

@@ -5,6 +5,7 @@
 #include <wayland-server-core.h>
 #include <wlr/backend.h>
 #include <wlr/types/wlr_output.h>
+#include <xkbcommon/xkbcommon.h>
 
 struct wlr_input_device;
 
@@ -23,6 +24,15 @@ struct wlr_backend *wlr_wl_backend_create(struct wl_display *display,
  */
 struct wl_display *wlr_wl_backend_get_remote_display(struct wlr_backend *backend);
 
+/**
+ * Sets the keyboard shortcut for toggle grabbing input of the focused wayland backend output.
+ *
+ * If modifiers_mask and keysym are zero or null, no shortcut will be used.
+ *
+ */
+void wlr_wl_backend_set_grab_input_shortcut(struct wlr_backend *backend, uint32_t modifiers_mask,
+		xkb_keysym_t keysym);
+
 /**
  * Adds a new output to this backend.
  *