Replaced volume with event-based version for pipewire

CMakeLists.txt

@@ -5,11 +5,14 @@ find_package(PkgConfig)
 
 set(POSITION_INDEPENDENT_CODE YES)
 set(C_STANDARD 11)
-add_compile_options(-Wall -Wextra -pedantic)
+add_compile_options(-Wall -Wextra)
 
 pkg_check_modules(CONSTRAIN REQUIRED x11 xi xfixes xrandr)
-
 add_library(constrain SHARED lib/constrain.c)
-
 target_link_libraries(constrain ${CONSTRAIN_LIBRARIES})
 target_include_directories(constrain PUBLIC ${CONSTRAIN_INCLUDE_DIRS})
+
+pkg_check_modules(PWCALL REQUIRED luajit gobject-2.0)
+add_library(pwcall SHARED lib/pwcall.cxx)
+target_link_libraries(pwcall ${PWCALL_LIBRARIES})
+target_include_directories(pwcall PUBLIC ${PWCALL_INCLUDE_DIRS})

Makefile

@@ -13,9 +13,13 @@ deploy: build
 
 .PHONY: build
 build:
-	cmake -S . -B build
+	cmake -S . -B build -G Ninja
 	cmake --build build
 
+.PHONY: clean
+clean:
+	rm -vfr build
+
 .PHONY: luacheck
 luacheck:
 	luacheck $(LUA_FILES)

lib/pwcall.cxx

@@ -0,0 +1,55 @@
+#define SOL_ALL_SAFETIES_ON 1
+#include <glib.h>
+#include <glib-object.h>
+#include "sol.hpp"
+
+static guint default_node_sig = 0, get_volume_sig = 0, set_volume_sig = 0;
+
+static guint default_node(gpointer api) {
+    if (default_node_sig == 0)
+        default_node_sig = g_signal_lookup("get-default-node", G_TYPE_FROM_INSTANCE(api));
+
+    guint retval;
+    g_signal_emit(api, default_node_sig, 0, "Audio/Sink", &retval);
+    return retval;
+}
+
+static std::tuple<guint, bool> get_volume(gpointer api, guint32 id) {
+    if (get_volume_sig == 0)
+        get_volume_sig = g_signal_lookup("get-volume", G_TYPE_FROM_INSTANCE(api));
+
+    GVariant *variant = nullptr;
+    g_signal_emit(api, get_volume_sig, 0, id, &variant);
+
+    gdouble volumed;
+    gboolean mute;
+    g_variant_lookup(variant, "volume", "d", &volumed);
+    g_variant_lookup(variant, "mute", "b", &mute);
+    if (variant) g_variant_unref(variant);
+
+    return std::tuple<guint, bool>(std::round(volumed * 100.0), mute == 1);
+}
+
+static void set_volume(gpointer api, guint32 id, guint voli, bool mute) {
+    if (set_volume_sig == 0)
+        set_volume_sig = g_signal_lookup("set-volume", G_TYPE_FROM_INSTANCE(api));
+
+    g_auto(GVariantBuilder) b = G_VARIANT_BUILDER_INIT(G_VARIANT_TYPE_VARDICT);
+    g_variant_builder_add(&b, "{sv}", "volume", g_variant_new_double(((gdouble)voli)/100));
+    g_variant_builder_add(&b, "{sv}", "mute", g_variant_new_boolean(mute ? TRUE : FALSE));
+
+    GVariant *variant = g_variant_builder_end(&b);
+    gboolean res;
+    g_signal_emit(api, set_volume_sig, 0, id, variant, &res);
+}
+
+extern "C" int luaopen_libpwcall(lua_State *L) {
+    sol::state_view lua(L);
+    auto tbl = lua.create_table();
+    tbl.set_function("default_node", default_node);
+    tbl.set_function("get_volume", get_volume);
+    tbl.set_function("set_volume", set_volume);
+    sol::stack::push(L, tbl);
+    return 1;
+}
+

src/util/path.lua

@@ -1,7 +1,3 @@
-local fs = require('gears.filesystem')
-
-print(awesome.conffile)
-
 return {
     conf_dir = awesome.conffile:match('^(.+)/')
 }

src/util/volume.lua

@@ -1,23 +1,101 @@
+-- https://github.com/Alexays/Waybar/blob/master/src/modules/wireplumber.cpp
+-- https://gitlab.freedesktop.org/pipewire/wireplumber/-/blob/master/modules/module-default-nodes-api.c
+-- https://gitlab.freedesktop.org/pipewire/wireplumber/-/blob/master/modules/module-mixer-api.c
+
 local volume_changed_signal = 'volume_changed'
 
-local function toggle_mute()
-    os.execute('wpctl set-mute @DEFAULT_AUDIO_SINK@ toggle')
-    awesome.emit_signal(volume_changed_signal)
-end
+if _G.volume_control == nil then
+    print('[volume_control] init')
+    local lgi = require('lgi')
+    ---@class (exact) VolumeControl
+    ---@field pw_call {}
+    ---@field lgi any
+    ---@field wp any
+    ---@field glib any
+    ---@field gobject any
+    ---@field core any
+    ---@field om any
+    ---@field node_api { _native: any } | nil
+    ---@field mixer_api { scale: number, _native: any } | nil
+    ---@field node_id integer
+    ---@field volume integer
+    ---@field mute boolean
+    local volume_control = {
+        pw_call = require('libpwcall'),
+        lgi = lgi,
+        wp = lgi.Wp,
+        glib = lgi.GLib,
+        gobject = lgi.GObject,
+        core = nil,
+        om = nil,
+        node_api = nil,
+        mixer_api = nil,
+        node_id = 0,
+        volume = 0,
+        mute = false
+    }
 
-local function vol_up()
-    os.execute('wpctl set-volume @DEFAULT_AUDIO_SINK@ 1%+')
-    awesome.emit_signal(volume_changed_signal)
-end
+    function volume_control:get_default_node() self.node_id = volume_control.pw_call.default_node(self.node_api._native) end
+    function volume_control:set_volume(vol, m) volume_control.pw_call.set_volume(self.mixer_api._native, self.node_id, vol, m) end
+    function volume_control:toggle_mute() self:set_volume(self.volume, not self.mute) end
+    function volume_control:volume_delta(d) self:set_volume(self.volume + d, self.mute) end
+    function volume_control:get_volume()
+        self.volume, self.mute = volume_control.pw_call.get_volume(self.mixer_api._native, self.node_id)
+        awesome.emit_signal(volume_changed_signal, self.volume, self.mute)
+    end
 
-local function vol_down()
-    os.execute('wpctl set-volume @DEFAULT_AUDIO_SINK@ 1%-')
-    awesome.emit_signal(volume_changed_signal)
+    function volume_control:om_installed()
+        self:get_default_node()
+        self:get_volume()
+        self.gobject.signal_connect_closure(self.node_api, 'changed', self.gobject.Closure(function(_)
+            volume_control:get_default_node()
+            volume_control:get_volume()
+        end))
+        self.gobject.signal_connect_closure(self.mixer_api, 'changed', self.gobject.Closure(function(_, nid)
+            if nid ~= volume_control.node_id then return end
+            volume_control:get_volume()
+        end))
+    end
+
+    function volume_control:init()
+        self.wp.init(self.wp.InitFlags.PIPEWIRE)
+        self.core = self.wp.Core.new(nil, nil, nil)
+        self.om = self.wp.ObjectManager.new()
+        self.om.on_installed = function() self:om_installed() end
+
+        local int = self.wp.ObjectInterest.new_type('WpNode')
+        int:add_constraint(self.wp.ConstraintType.PW_PROPERTY, 'media.class', self.wp.ConstraintVerb.EQUALS, self.glib.Variant.new_string('Audio/Sink'))
+        self.om:add_interest_full(int)
+        if self.core:connect() == 0 then error('Failed to connect to pipewire') end
+        local pending = 2
+        local function plugin_loaded(p, res)
+            if volume_control.wp.Object.activate_finish(p, res) == 0 then error('Failed to activate plugin') end
+            pending = pending - 1
+            if pending ~= 0 then return end
+            volume_control.core:install_object_manager(volume_control.om)
+        end
+
+        self.core:load_component('libwireplumber-module-default-nodes-api', 'module', nil, 'default-nodes-api', nil, function(_, res)
+            if volume_control.core:load_component_finish(res, nil) == 0 then error('Failed to load default-nodes-api') end
+            volume_control.core:load_component('libwireplumber-module-mixer-api', 'module', nil, 'mixer-api', nil, function(_, res2)
+                if volume_control.core:load_component_finish(res2, nil) == 0 then error('Failed to load mixer-api') end
+                volume_control.node_api = volume_control.wp.Plugin.find(volume_control.core, 'default-nodes-api')
+                volume_control.wp.Object.activate(volume_control.node_api, volume_control.wp.PluginFeatures.ENABLED, nil, plugin_loaded)
+                volume_control.mixer_api = volume_control.wp.Plugin.find(volume_control.core, 'mixer-api')
+                volume_control.mixer_api.scale = 1
+                volume_control.wp.Object.activate(volume_control.mixer_api, volume_control.wp.PluginFeatures.ENABLED, nil, plugin_loaded)
+            end, nil)
+        end, nil)
+    end
+
+    volume_control:init()
+
+    _G.volume_control = volume_control
 end
 
 return {
     volume_changed_signal = volume_changed_signal,
-    toggle_mute = toggle_mute,
-    vol_up = vol_up,
-    vol_down = vol_down,
+    toggle_mute = function() _G.volume_control:toggle_mute() end,
+    vol_up = function() _G.volume_control:volume_delta(1) end,
+    vol_down = function() _G.volume_control:volume_delta(-1) end,
 }

src/widgets/5_vol.lua

@@ -1,44 +1,23 @@
 local wibox = require('wibox')
 local awful = require('awful')
-local gears = require('gears')
 local theme = require('src.theme')
 local volume = require('src.util.volume')
 
 local volumeicon = wibox.widget.imagebox(theme.widget_vol_mute)
 local volume_widget = wibox.widget.textbox()
 
-local function spawn_callback(stdout)
-    local volume_str = stdout:sub(9,12):gsub('[.]', '')
-    local mute = stdout:match('MUTED')
-    local level = tonumber(volume_str)
-    if level == nil then
-        volume_widget:set_markup('Waiting')
-        return
-    end
+awesome.connect_signal(volume.volume_changed_signal, function(vol, mute)
     if mute then
         volumeicon:set_image(theme.widget_vol_mute)
-    elseif level == 0 then
+    elseif vol == 0 then
         volumeicon:set_image(theme.widget_vol_mute)
-    elseif level <= 50 then
+    elseif vol <= 50 then
         volumeicon:set_image(theme.widget_vol_low)
     else
         volumeicon:set_image(theme.widget_vol_high)
     end
-    volume_widget:set_markup(level .. (mute  and 'M' or '%'))
-end
-
-local function timer_callback()
-    awful.spawn.easy_async('wpctl get-volume @DEFAULT_AUDIO_SINK@', spawn_callback)
-end
-
-local volume_timer = gears.timer {
-    timeout = 30,
-    autostart = true,
-    call_now = true,
-    callback = timer_callback
-}
-
-awesome.connect_signal(volume.volume_changed_signal, function() volume_timer:emit_signal('timeout') end)
+    volume_widget.text = vol .. (mute  and 'M' or '%')
+end)
 
 local volumebuttons = awful.util.table.join(
     awful.button({}, 1, volume.toggle_mute),