Prevent focused application from receiving global hotkey keys on wayland as well (massive hack)

1 files changed, 101 insertions, 11 deletions

diff --git a/tools/gsr-global-hotkeys/keyboard_event.c b/tools/gsr-global-hotkeys/keyboard_event.c
index 9cc518a..86b7248 100644
--- a/tools/gsr-global-hotkeys/keyboard_event.c
+++ b/tools/gsr-global-hotkeys/keyboard_event.c
@@ -14,6 +14,9 @@
 
 /* LINUX */
 #include <linux/input.h>
+#include <linux/uinput.h>
+
+#define GSR_UI_VIRTUAL_KEYBOARD_NAME "gsr-ui virtual keyboard"
 
 /*
     We could get initial keyboard state with:
@@ -21,7 +24,11 @@
     ioctl(fd, EVIOCGKEY(sizeof(key_states)), key_states), but ignore that for now
 */
 
-static void keyboard_event_process_input_event_data(keyboard_event *self, int fd, key_callback callback, void *userdata) {
+static bool keyboard_event_has_exclusive_grab(const keyboard_event *self) {
+    return self->uinput_fd > 0;
+}
+
+static void keyboard_event_process_input_event_data(keyboard_event *self, const event_extra_data *extra_data, int fd, key_callback callback, void *userdata) {
     struct input_event event;
     if(read(fd, &event, sizeof(event)) != sizeof(event)) {
         fprintf(stderr, "Error: failed to read input event data\n");
@@ -76,11 +83,19 @@ static void keyboard_event_process_input_event_data(keyboard_event *self, int fd
                 if(meta_pressed)
                     modifiers |= KEYBOARD_MODKEY_SUPER;
 
-                callback(event.code, modifiers, event.value, userdata);
+                if(!callback(event.code, modifiers, event.value, userdata))
+                    return;
+
                 break;
             }
         }
     }
+
+    if(keyboard_event_has_exclusive_grab(self) && extra_data->grabbed) {
+        /* TODO: Error check? */
+        if(write(self->uinput_fd, &event, sizeof(event)) != sizeof(event))
+            fprintf(stderr, "Error: failed to write event data to virtual keyboard for exclusively grabbed device\n");
+    }
 }
 
 /* Returns -1 if invalid format. Expected |dev_input_filepath| to be in format /dev/input/eventN */
@@ -96,7 +111,7 @@ static int get_dev_input_id_from_filepath(const char *dev_input_filepath) {
 
 static bool keyboard_event_has_event_with_dev_input_fd(keyboard_event *self, int dev_input_id) {
     for(int i = 0; i < self->num_event_polls; ++i) {
-        if(self->dev_input_ids[i] == dev_input_id)
+        if(self->event_extra_data[i].dev_input_id == dev_input_id)
             return true;
     }
     return false;
@@ -120,7 +135,7 @@ static bool keyboard_event_try_add_device_if_keyboard(keyboard_event *self, cons
 
     unsigned long evbit = 0;
     ioctl(fd, EVIOCGBIT(0, sizeof(evbit)), &evbit);
-    if(evbit & (1 << EV_KEY)) {
+    if(strcmp(device_name, GSR_UI_VIRTUAL_KEYBOARD_NAME) != 0 && (evbit & (1 << EV_KEY))) {
         unsigned char key_bits[KEY_MAX/8 + 1] = {0};
         ioctl(fd, EVIOCGBIT(EV_KEY, sizeof(key_bits)), &key_bits);
 
@@ -129,13 +144,24 @@ static bool keyboard_event_try_add_device_if_keyboard(keyboard_event *self, cons
         const bool supports_key_events = key_bits[key_test/8] & (1 << (key_test % 8));
         if(supports_key_events) {
             if(self->num_event_polls < MAX_EVENT_POLLS) {
+                bool grabbed = false;
+                if(keyboard_event_has_exclusive_grab(self)) {
+                    grabbed = ioctl(fd, EVIOCGRAB, 1) != -1;
+                    if(!grabbed)
+                        fprintf(stderr, "Warning: failed to exclusively grab device %s. The focused application may receive keys used for global hotkeys\n", device_name);
+                }
+
                 //fprintf(stderr, "%s (%s) supports key inputs\n", dev_input_filepath, device_name);
                 self->event_polls[self->num_event_polls] = (struct pollfd) {
                     .fd = fd,
                     .events = POLLIN,
                     .revents = 0
                 };
-                self->dev_input_ids[self->num_event_polls] = dev_input_id;
+
+                self->event_extra_data[self->num_event_polls] = (event_extra_data) {
+                    .dev_input_id = dev_input_id,
+                    .grabbed = grabbed
+                };
 
                 ++self->num_event_polls;
                 return true;
@@ -180,23 +206,79 @@ static void keyboard_event_remove_event(keyboard_event *self, int index) {
     close(self->event_polls[index].fd);
     for(int j = index + 1; j < self->num_event_polls; ++j) {
         self->event_polls[j - 1] = self->event_polls[j];
-        self->dev_input_ids[j - 1] = self->dev_input_ids[j];
+        self->event_extra_data[j - 1] = self->event_extra_data[j];
     }
     --self->num_event_polls;
 }
 
-bool keyboard_event_init(keyboard_event *self, bool poll_stdout_error) {
+/* Returns the fd to the uinput */
+static int setup_virtual_keyboard_input(const char *name) {
+    /* TODO: O_NONBLOCK? */
+    int fd = open("/dev/uinput", O_WRONLY);
+    if(fd == -1) {
+        fd = open("/dev/input/uinput", O_WRONLY);
+        if(fd == -1) {
+            fprintf(stderr, "Warning: failed to setup virtual device for exclusive grab (failed to open /dev/uinput or /dev/input/uinput), error: %s\n", strerror(errno));
+            return -1;
+        }
+    }
+
+    bool success = true;
+    success &= (ioctl(fd, UI_SET_EVBIT, EV_KEY) != -1);
+    for(int i = 1; i < KEY_MAX; ++i) {
+        success &= (ioctl(fd, UI_SET_KEYBIT, i) != -1);
+    }
+
+    int ui_version = 0;
+    success &= (ioctl(fd, UI_GET_VERSION, &ui_version) != -1);
+
+    if(ui_version >= 5) {
+        struct uinput_setup usetup;
+        memset(&usetup, 0, sizeof(usetup));
+        usetup.id.bustype = BUS_USB;
+        usetup.id.vendor = 0xdec0;
+        usetup.id.product = 0x5eba;
+        snprintf(usetup.name, sizeof(usetup.name), "%s", name);
+        success &= (ioctl(fd, UI_DEV_SETUP, &usetup) != -1);
+    } else {
+        struct uinput_user_dev uud;
+        memset(&uud, 0, sizeof(uud));
+        snprintf(uud.name, UINPUT_MAX_NAME_SIZE, "%s", name);
+        if(write(fd, &uud, sizeof(uud)) != sizeof(uud))
+            success = false;
+    }
+
+    success &= (ioctl(fd, UI_DEV_CREATE) != -1);
+    if(!success) {
+        close(fd);
+        return -1;
+    }
+
+    return fd;
+}
+
+bool keyboard_event_init(keyboard_event *self, bool poll_stdout_error, bool exclusive_grab) {
     memset(self, 0, sizeof(*self));
     self->stdout_event_index = -1;
     self->hotplug_event_index = -1;
 
+    if(exclusive_grab) {
+        // TODO: If this fails, try /dev/input/uinput instead
+        self->uinput_fd = setup_virtual_keyboard_input(GSR_UI_VIRTUAL_KEYBOARD_NAME);
+        if(self->uinput_fd <= 0)
+            fprintf(stderr, "Warning: failed to setup virtual keyboard input for exclusive grab. The focused application will receive keys used for global hotkeys\n");
+    }
+
     if(poll_stdout_error) {
         self->event_polls[self->num_event_polls] = (struct pollfd) {
             .fd = STDOUT_FILENO,
             .events = 0,
             .revents = 0
         };
-        self->dev_input_ids[self->num_event_polls] = -1;
+        self->event_extra_data[self->num_event_polls] = (event_extra_data) {
+            .dev_input_id = -1,
+            .grabbed = false
+        };
 
         self->stdout_event_index = self->num_event_polls;
         ++self->num_event_polls;
@@ -208,7 +290,10 @@ bool keyboard_event_init(keyboard_event *self, bool poll_stdout_error) {
             .events = POLLIN,
             .revents = 0
         };
-        self->dev_input_ids[self->num_event_polls] = -1;
+        self->event_extra_data[self->num_event_polls] = (event_extra_data) {
+            .dev_input_id = -1,
+            .grabbed = false
+        };
 
         self->hotplug_event_index = self->num_event_polls;
         ++self->num_event_polls;
@@ -228,6 +313,11 @@ bool keyboard_event_init(keyboard_event *self, bool poll_stdout_error) {
 }
 
 void keyboard_event_deinit(keyboard_event *self) {
+    if(self->uinput_fd > 0) {
+        close(self->uinput_fd);
+        self->uinput_fd = -1;
+    }
+
     for(int i = 0; i < self->num_event_polls; ++i) {
         close(self->event_polls[i].fd);
     }
@@ -264,10 +354,10 @@ void keyboard_event_poll_events(keyboard_event *self, int timeout_milliseconds,
             /* Device is added to end of |event_polls| so it's ok to add while iterating it via index */
             hotplug_event_process_event_data(&self->hotplug_ev, self->event_polls[i].fd, on_device_added_callback, self);
         else
-            keyboard_event_process_input_event_data(self, self->event_polls[i].fd, callback, userdata);
+            keyboard_event_process_input_event_data(self, &self->event_extra_data[i], self->event_polls[i].fd, callback, userdata);
     }
 }
 
-bool keyboard_event_stdout_has_failed(keyboard_event *self) {
+bool keyboard_event_stdout_has_failed(const keyboard_event *self) {
     return self->stdout_failed;
 }