added documentation on awesome incl. a guide on focus steal hardening

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David Hobach 2018-04-03 22:22:37 +02:00
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---
layout: doc
title: awesome
permalink: /doc/awesome/
redirect_from:
- /en/doc/awesome/
- /doc/awesome/
---
# Using awesome in dom0
## Qubes-specific features
* support for the Qubes OS window colors
* rudimentary support for the Qubes application menu entries following the freedesktop standard
* support for custom filters and menu entries
## Installation
awesome can be installed with the standard dom0 installation mechanisms.
$ sudo qubes-dom0-update awesome
That's it. After logging out, you can select awesome in the login manager.
## Development
To [contribute code](/doc/contributing/) you may clone the awesome repository as follows:
$ git clone https://github.com/QubesOS/qubes-desktop-linux-awesome
For build instructions please check the repository _README_.
The repository attempts to follow the upstream Fedora repository.
## Common customizations
This section focuses on Qubes-specific customizations. For generic awesome customizations you might want to have a look at the [awesome website](https://awesomewm.org).
Customizations for awesome are usually done at `~/.config/awesome/rc.lua`. The default file can be found at `/etc/xdg/awesome/rc.lua`.
### Application menu
Starting from Qubes 4.0 application menu entries specific to awesome can be put into `~/.config/awesome/xdg-menu/` following the freedesktop standard. The folder might have to be created.
### Focus steal hardening
The default Qubes OS awesome installation comes with the defaults set by the awesome developers for focus changes. Some users may want more tight control over window focus changes - especially since focus changes can have security implications when sensitive data is provided to an incorrect application or even qube.
#### Definition
For the below example we'll define _wanted focus changes_ as one of the below:
* mouse move & click afterwards
* workspace/tag change
* pre-defined key combinations for focus changes (e.g. Mod-j & Mod-k)
* tag assignments and unassignments
Everything else is considered an unwanted _focus steal_.
In particular the following events are not meant to cause a focus change:
* new window created
* a window was closed
* application request
* mouse move without click (sloppy focus)
For the below example other requests from applications to the window manager are meant to be ignored in general as well, e.g.:
* windows shouldn't be able to maximize themselves without the user giving a respective command to the WM (simple test: Firefox F11 next to another window)
* windows shouldn't be able to change their size themselves
* windows shouldn't be able to modify their borders in any way
Users may want to adjust their definitions and respective implementations according to their needs.
#### Implementation
The implementation may be specific to the awesome version you're running. This guide refers to awesome version 3.5.9 which is available to Qubes 3.2 and Qubes 4.0 users.
Please keep in mind that this guide may not be conclusive. Your mileage may vary.
##### Change the autofocus implementation
The line `require("awful.autofocus")` in your _rc.lua_ implements various focus-related features for your awesome instance.
In order to customise these, you can copy the file `/usr/share/awesome/lib/awful/autofocus.lua` to e.g. `~/.config/awesome/autofocus_custom.lua` and replace the line above with `require("autofocus_custom")`.
Then you can customise the focus behavior. According to our above definitions it would look as follows:
```lua
---autofocus_custom.lua
local client = client
local screen = screen
local aclient = require("awful.client")
local atag = require("awful.tag")
--- When loaded, this module makes sure that there's always a client that will have focus
-- on events such as tag switching, client unmanaging, etc.
-- awful.autofocus
-- Give focus when clients appear/disappear and no one else has focus.
-- @param obj An object that should have a .screen property.
function check_focus(obj)
-- When no visible client has the focus...
if not client.focus or not client.focus:isvisible() then
local c = aclient.focus.history.get(obj.screen, 0)
if c then client.focus = c end
end
end
-- Give focus on tag selection change.
-- @param tag A tag object
function check_focus_tag(t)
local s = atag.getscreen(t)
if not s then return end
check_focus({ screen = s })
if client.focus and client.focus.screen ~= s then
local c = aclient.focus.history.get(s, 0)
if c then client.focus = c end
end
end
--made above functions global & removed some focus switches below (user interaction required instead)
--clear any focus
function clear_focus()
--unfortunately this doesn't work at the moment
--cf. https://github.com/awesomeWM/awesome/issues/164
--(Qubes uses an older awesome version that doesn't have the fix yet)
--client.focus = nil
end
atag.attached_connect_signal(nil, "property::selected", check_focus_tag)
client.connect_signal("unmanage", clear_focus)
client.connect_signal("tagged", check_focus)
client.connect_signal("untagged", check_focus)
client.connect_signal("property::hidden", clear_focus)
client.connect_signal("property::minimized", clear_focus)
```
##### Remove unwanted focus changing key bindings
The mouse bindings
```lua
awful.button({ }, 4, awful.tag.viewnext),
awful.button({ }, 5, awful.tag.viewprev)
```
in the default _rc.lua_ may cause tag and thus focus changes without keyboard interaction and tend to happen accidentally. This doesn't suit our definition from above and should therefore be removed or commented out.
##### Adjust client rules
The default client rule allows certain focus changes via `focus = awful.client.focus.filter`. These changes can be prevented entirely by setting `focus = false`.
Alternatively users may provide their own focus filter functions.
##### Disable sloppy focus
In your _rc.lua_ you'll find a section such as
```lua
-- Enable sloppy focus
c:connect_signal("mouse::enter", function(c)
if awful.layout.get(c.screen) ~= awful.layout.suit.magnifier
and awful.client.focus.filter(c) then
client.focus = c
end
end)
```
These enable _sloppy focus_ aka focus changes on mouse movements (without clicking) and should be removed or commented out to disable that behaviour.
##### Ignore requests from applications to the window manager
Handling of such requests is currently mostly implemented by awesome in the file `/usr/share/awesome/lib/awful/ewmh.lua`. You can either comment out the respective `client.connect_singal()` lines in that file (it will change back after each awesome update though) or disconnect the signals in your _rc.lua_.
As of awesome 3.5.9 this however is apparently only possible for signals connected to global functions, i.e. currently only the below signals can be disconnected in the _rc.lua_:
```lua
local ewmh = require("awful.ewmh")
client.disconnect_signal("request::activate", ewmh.activate)
client.disconnect_signal("request::tag", ewmh.tag)
```
The signal names may change across awesome versions.