Mouse grabbing and Moving on X11

[Gamma-42]

WslLogs-2024-11-30_05-23-24.zip

Windows Version

Microsoft Windows [Version 10.0.22631.4460]

WSL Version

2.3.26.0

Are you using WSL 1 or WSL 2?

• WSL 2
• WSL 1

Kernel Version

5.15.167.4-1

Distro Version

Ubuntu 22.04

Other Software

No response

Repro Steps

Simply open an X11 Window with C and try to use the XGrabPointer function or try to define an "invisible" (empty texture) cursor with XDefineCursor.
I put my code in Diagnostic Log.
compile with: cc filename.c -lX11 -lXext -I/usr/include -L/usr/lib
run with: ./a.out

Expected Behavior

For XGrabPointer the mouse events should only be passed to the X11 Window, so that the Mouse is basically trapped inside. The window basically reserves the mouse pointer.

For XDefineCursor the Cursor Image should be set to the passed Image.
I tested these functions also on my other laptop where the same Ubuntu is installed normally (without wsl) everything there works as expected.

Actual Behavior

Even after XGrapPointer the mouse moves freely over the screen and isn't reserved by the window.
Instead of an custom image the cursor also just shows the standard image. (Changing the cursor image with XCreateFontCursor works)

Diagnostic Logs

#include <X11/Xlib.h>
#include <X11/cursorfont.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

struct color_struct {
unsigned long black, white;
};

#define SCREEN (DefaultScreen(display))
#define ROOT_WINDOW (DefaultRootWindow(display))

Cursor create_invisible_cursor(Display *display, Window root) {
Pixmap bitmap_no_data;
XColor black;
static char no_data[] = { 0,0,0,0,0,0,0,0 };
black.red = black.green = black.blue = 0;

bitmap_no_data = XCreateBitmapFromData(display, root, no_data, 8, 8);
return XCreatePixmapCursor(display, bitmap_no_data, bitmap_no_data, &black, &black, 0, 0);

}

int main(void) {
int depth;
char *display_name;
struct color_struct *color = malloc(sizeof(struct color_struct));

Display *display;
Window main_window;

display = XOpenDisplay(0);
assert(display);

printf("Default display opened\n");
printf("Size: %dx%d\n", XDisplayWidth(display, SCREEN),
    XDisplayHeight(display, SCREEN));

color->black = XBlackPixel(display, SCREEN);
color->white = XWhitePixel(display, SCREEN);

main_window = XCreateSimpleWindow(display, ROOT_WINDOW, 0, 0, 200, 100, 0,
    color->black, color->black);
assert(main_window);

printf("Main window created\n");

XMapWindow(display, main_window);
XGrabPointer(display, main_window, True, 0, GrabModeAsync, GrabModeAsync, main_window, None, CurrentTime);

// Create and set an invisible cursor
Cursor invisible_cursor = create_invisible_cursor(display, ROOT_WINDOW);
XDefineCursor(display, main_window, invisible_cursor);
XFlush(display);

while (1) {
    // Move the pointer to the top-left corner of the main window
    XWarpPointer(display, None, main_window, 0, 0, 0, 0, 0, 0);
    XGrabPointer(display, main_window, True, 0, GrabModeAsync, GrabModeAsync, main_window, None, CurrentTime);
    sleep(2);
    
}

// Cleanup (not reached in this example)
XFreeCursor(display, invisible_cursor);
free(color);
XCloseDisplay(display);

return 0;

}

[github-actions]

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Closed similar issues:

• mouse problem (#11722), similarity score: 0.71

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[github-actions]

Diagnostic information

Issue was edited and new log file was found: https://github.com/user-attachments/files/17964171/WslLogs-2024-11-30_05-23-24.zip
Detected appx version: 2.3.26.0

[Gamma-42]

Adding a Log seems unnecessary, but ok

[MamiyaOtaru]

This is basically #376

see also #374 and #240

It's unfortunately been around and known for years :(