xorg-show-grabs.d

#!/bin/env rdmd
module xorg_show_grabs;

import std.algorithm;
import std.conv;
import std.exception;
import std.getopt;
import std.stdio;
import std.string;

void main(string[] args)
{
	const defaultLogFileName = "/var/log/Xorg.0.log";
	string logFileName = defaultLogFileName;

	auto help = getopt(args,
		"xorg-log", "Path to the Xorg log file, by default: " ~ defaultLogFileName, &logFileName,
	);
	if (help.helpWanted)
		return defaultGetoptPrinter("xorg-show-grabs - Extract and display key grabs from Xorg log in a human-readable way.

Usage:

	1. Run:

	   xdotool key XF86LogGrabInfo

	2. Run this program.

Options:
",
			help.options);

	bool[string][string] results;

	string currentClient;
	bool currentGrab;
	int currentKey, currentMod;

	foreach (l; File(logFileName).byLine())
	{
		auto line = l.findSplit("] ")[2];
		if (!line.length)
			continue;

		if (line == "Printing all currently registered grabs")
			results = null;
		else
		if (line.skipOver("  Printing all registered grabs of client pid "))
			currentClient = line.idup.strip();
		else
		if (line.skipOver("  grab "))
		{
			currentGrab = false;
			line.skipUntil(' ');
			if (!line.startsWith("(core), type 'KeyPress' on window "))
				continue;
			currentGrab = true;
		}
		else
		if (line.skipOver("    device "))
		{
			if (!line.startsWith("'Virtual core keyboard' ("))
				currentGrab = false;
		}
		else
		if (line.skipOver("    detail "))
		{
			currentKey = line.skipUntil(' ').to!int;
			if (!line.skipOver("(mask 0), modifiersDetail "))
				continue;
			currentMod = line.skipUntil(' ').to!int;
		}
		else
		if (line.skipOver("    owner-events "))
		{
			if (currentGrab)
			{
				auto key = xModToString(currentMod)~xKeyToString(currentKey);
				results[currentClient][key] = true;
				currentGrab = false;
			}
		}
	}
	foreach (client; results.keys.sort())
	{
		writefln("%s:", client);
		foreach (key; results[client].keys.sort())
			writefln("  %s", key);
	}
}

auto skipUntil(T)(ref T[] s, T c)
{
	auto i = s.indexOf(c);
	if (i < 0)
	{
		s = null;
		return null;
	}
	auto result = s[0..i];
	s = s[i+1..$];
	return result;
}

pragma(lib, "X11");

import core.stdc.config;

struct Display;
alias KeyCode = ubyte;
alias KeySym = c_ulong;

extern(C) Display* XOpenDisplay(const(char)*);
extern(C) KeySym XkbKeycodeToKeysym(Display *dpy, KeyCode kc, uint group, uint level);
extern(C) char* XKeysymToString(KeySym);

string xKeyToString(int key)
{
	static Display *dpy = null;
	if (!dpy)
		dpy = enforce(XOpenDisplay(":0"), "Can't open display!");

	KeySym ks = XkbKeycodeToKeysym(dpy, cast(ubyte)key, 0, 0);

	return XKeysymToString(ks).to!string();
}

string xModToString(int mod)
{
	//							1			2			4			8			0x10		0x20		0x40		0x80
	//const string[] names = [	"Shift",	"Lock",		"Control",	"Mod1",		"Mod2",		"Mod3",		"Mod4",		"Mod5"];
	//const string[] names = [	"Shift",	"Lock",		"Control",	"Alt" ,		"Mod2",		"Mod3",		"Win" ,		"Mod5"];
	const string[] names = [	"Shift",	"Lock",		"Control",	"Mod1(Alt)" , "Mod2",	"Mod3",		"Mod4(Win)" ,"Mod5"];
	string result;
	foreach (i, name; names)
		if ((1<<i) & mod)
			result ~= name ~ " + ";
	return result;
}

This is programmed in language D. To get an executable file, one can install packages gdc (GNU D compiler) and libx11-dev then run gdc -o xorg-show-grabs xorg-show-grabs.d -lX11.

On Arch / Manjaro, gdc unfortunately does not build anymore:

$ gdc -o xorg-show-grabs xorg-show-grabs.d -lX11 -llto_plugin
gdc: fatal error: -fuse-linker-plugin, but liblto_plugin.so not found

Fortunately, dmd (the D reference compiler) is even easier:

$ dmd xorg-show-grabs.d

The binary is called xorg-show-grabs

Marry me!

On Arch / Manjaro, gdc unfortunately does not build anymore

In case anyone else ends up here, that's because the lto plugin was folded into gdc. You just leave that one off.