This reverts commit 2d33c20231 and
reapplies various patches for memory leaks.
The reason for the revert was a bug for a maximum duration interval
which caused sleep_for() to cause unpredictable behavior.
In the previous fix for a passed max duration, the assumption was made
that at maximum one second will pass between the duration assignment and
the std::condition_variable::sleep_for() call.
This implementation makes the behavior more predictable by using
sleep_until() instead to emulate the sleep_for() behavior.
The standard library has the implicit requirement that for
std::condition_variable::sleep_for() the duration must not cause an
overflow if added to the current time.
This commit will reduce the duration accordingly to fit into the
duration type.
This keeps the function consistent with sleep_until() and sleep_for()
which both can be interrupted.
This is relevant to allow an update via a "signal" without an "interval"
in a custom module.
summary:
-------
This commit adds xdg-desktop-portal support to waybar. If a portal
supporting `org.freedesktop.portal.Settings` exists, then it will be
queried for the current colorscheme. This colorscheme will then be used
to prefer a `style-light.css` or `style-dark.css` over the basic
`style.css`.
technical details:
-----------------
Appearance is provided by several libraries, such as libhandy (mobile)
and libadwaita. However, waybar links to neither of these libraries. As
the amount of code required to communicate with xdg-desktop portal as a
client is rather minimal, I believe doing so is better than linking to
an additional library.
The Gio library for communicating with dbus is rather messy, Instead of
the `Portal` class containing a `Gio::Dbus::Proxy`, it extends it which
simplifies signal handling.
`Portal` then exposes its own signal, which can be listened to by waybar
to update CSS.
For a reference implementation, please see another one of my projects:
https://github.com/4e554c4c/darkman.nvim/blob/main/portal.go
test plan:
---------
If no desktop portal which provides `Settings` exists, then waybar
continues with the log line
```
[2023-09-06 14:14:37.754] [info] Unable to receive desktop appearance: GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such interface “org.freedesktop.portal.Settings” on object at path /org/freedesktop/portal/desktop
```
Furthermore, if `style-light.css` or `style-dark.css` do not exist, then
`style.css` will still be searched for.
Waybar has been tested with both light and dark startup. E.g. if the
appearance is dark on startup the log lines
```
[2023-09-06 14:27:45.379] [info] Discovered appearance 'dark'
[2023-09-06 14:27:45.379] [debug] Try expanding: $XDG_CONFIG_HOME/waybar/style-dark.css
[2023-09-06 14:27:45.379] [debug] Found config file: $XDG_CONFIG_HOME/waybar/style-dark.css
[2023-09-06 14:27:45.379] [info] Using CSS file /home/pounce/.config/waybar/style-dark.css
```
will be observed.
If the color then changes to light during the operation of waybar, it
will change css files:
```
[2023-09-06 14:28:17.173] [info] Received new appearance 'dark'
[2023-09-06 14:28:17.173] [debug] Try expanding: $XDG_CONFIG_HOME/waybar/style-light.css
[2023-09-06 14:28:17.173] [debug] Found config file: $XDG_CONFIG_HOME/waybar/style-light.css
[2023-09-06 14:28:17.173] [info] Using CSS file /home/pounce/.config/waybar/style-light.css
```
Finally, tested resetting waybar and toggling style (works, and style is
only changed once).
fixes: Alexays/Waybar#1973
The segfaults were happening on GTK icon theme functions, which are
called via the C++ interface functions such as Gtk::IconTheme::has_icon.
There are multiple modules and threads using this functions on the default
icon theme by calling Gtk::IconTheme::get_default(), which returns the same
object for all callers, and was causing concurrent access to the same internal
data structures on the GTK lib. Even a seemingly read-only function such as
has_icon can cause writes due to the internal icon cache being updated.
To avoid this issues, a program wide global mutex must be used to ensure
a single thread is accessing the default icon theme instance.
This commit implements wrappers for the existing IconTheme function calls,
ensuring the global lock is held while calling the underling GTK functions.
Avoids a race where the pipe could be inherited by another process
spawning at about the same time. If the other process didn't exit
quickly (e.g. if it was a custom script that did its own looping), it
would keep the write end of the pipe open, and so reading from the pipe
to try to get the command's output would block.
This bug manifested as some custom modules randomly not appearing in the
bar, requiring a reload to fix. The custom script had run and exited,
but the pipe had been inherited by another process, and the thread that
updated the module's output was blocked trying to read from it.
