Wrong mouse position when col > 255

[Christian]

When the gnome-terminal (xterm, rxvt,..) has more than 255 columns and I click in a column on the right side of the 255th column the value of col in mouse_event is wrong. 256th column -> col=-33 257th column -> col=-32 and so on. I have looked a bit in the code and found this piece: (raw_display.py:427ff)

def _getch(self, timeout):
    ready = self._wait_for_input_ready(timeout)
    if self.gpm_mev is not None:
        if self.gpm_mev.stdout.fileno() in ready:
            self.gpm_event_pending = True
    if self._term_input_file.fileno() in ready:
        return ord(os.read(self._term_input_file.fileno(), 1))
    return -1

Values greater then 255 can't be read correct from stdin. So if gpm isn't available there should be some code that prevents this error. I don't know if there is another way to get the mouse position except from stdin, or if you have to ensure that the terminal isn't bigger then 255x255.

[ian]

In my testing I see the X coordinate works until column 222, then wraps around to -33 and counts up again. Makes sense as chr(33) indicates column 0. You can try running input_test.py to see the values.

So, I could accept those last 33 positions properly (map -33:-1 to 223:255), but I don't know of a fix that would allow reading larger coordinates. Something might be possible using the X protocol, but it would be a real hack.

[ian]

[7ecfec62eea6] is the best I can do with the information that is sent on stdin.