Add logind feature, with its 'inhibitor' module

The logind feature adds a new inhibitor module which allows to acquire
the inhibitor locks that logind presents.

Signed-off-by: Alexis Cellier <kernelserror@gmail.com>

include/factory.hpp

@@ -51,6 +51,9 @@
 #ifdef HAVE_LIBSNDIO
 #include "modules/sndio.hpp"
 #endif
+#ifdef HAVE_GIO_UNIX
+#include "modules/inhibitor.hpp"
+#endif
 #include "bar.hpp"
 #include "modules/custom.hpp"
 #include "modules/temperature.hpp"

include/modules/inhibitor.hpp

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <memory>
+
+#include <gio/gio.h>
+
+#include "ALabel.hpp"
+#include "bar.hpp"
+
+namespace waybar::modules {
+
+class Inhibitor : public ALabel {
+ public:
+  Inhibitor(const std::string&, const waybar::Bar&, const Json::Value&);
+  ~Inhibitor() override;
+  auto update() -> void;
+  auto activated() -> bool;
+
+ private:
+  auto handleToggle(::GdkEventButton* const& e) -> bool;
+
+  const std::unique_ptr<::GDBusConnection, void(*)(::GDBusConnection*)> dbus_;
+  const std::string inhibitors_;
+  int handle_ = -1;
+};
+
+} // namespace waybar::modules

meson.build

@@ -86,7 +86,7 @@ wayland_cursor = dependency('wayland-cursor')
 wayland_protos = dependency('wayland-protocols')
 gtkmm = dependency('gtkmm-3.0', version : ['>=3.22.0'])
 dbusmenu_gtk = dependency('dbusmenu-gtk3-0.4', required: get_option('dbusmenu-gtk'))
-giounix = dependency('gio-unix-2.0', required: get_option('dbusmenu-gtk'))
+giounix = dependency('gio-unix-2.0', required: (get_option('dbusmenu-gtk').enabled() or get_option('logind').enabled()))
 jsoncpp = dependency('jsoncpp')
 sigcpp = dependency('sigc++-2.0')
 libepoll = dependency('epoll-shim', required: false)
@@ -242,6 +242,11 @@ if libsndio.found()
     src_files += 'src/modules/sndio.cpp'
 endif
 
+if (giounix.found() and not get_option('logind').disabled())
+    add_project_arguments('-DHAVE_GIO_UNIX', language: 'cpp')
+    src_files += 'src/modules/inhibitor.cpp'
+endif
+
 if get_option('rfkill').enabled()
     if is_linux
         add_project_arguments('-DWANT_RFKILL', language: 'cpp')

meson_options.txt

@@ -10,5 +10,6 @@ option('mpd', type: 'feature', value: 'auto', description: 'Enable support for t
 option('gtk-layer-shell', type: 'feature', value: 'auto', description: 'Use gtk-layer-shell library for popups support')
 option('rfkill', type: 'feature', value: 'auto', description: 'Enable support for RFKILL')
 option('sndio', type: 'feature', value: 'auto', description: 'Enable support for sndio')
+option('logind', type: 'feature', value: 'auto', description: 'Enable support for logind')
 option('tests', type: 'feature', value: 'auto', description: 'Enable tests')
 option('experimental', type : 'boolean', value : false, description: 'Enable experimental features')

src/factory.cpp

@@ -94,6 +94,11 @@ waybar::AModule* waybar::Factory::makeModule(const std::string& name) const {
     if (ref == "sndio") {
       return new waybar::modules::Sndio(id, config_[name]);
     }
+#endif
+#ifdef HAVE_GIO_UNIX
+    if (ref == "inhibitor") {
+      return new waybar::modules::Inhibitor(id, bar_, config_[name]);
+    }
 #endif
     if (ref == "temperature") {
       return new waybar::modules::Temperature(id, config_[name]);

src/modules/inhibitor.cpp

@@ -0,0 +1,175 @@
+#include "modules/inhibitor.hpp"
+
+#include <gio/gio.h>
+#include <gio/gunixfdlist.h>
+#include <spdlog/spdlog.h>
+
+namespace {
+
+using DBus = std::unique_ptr<GDBusConnection, void(*)(GDBusConnection*)>;
+
+auto dbus() -> DBus {
+  GError *error = nullptr;
+  GDBusConnection* connection =
+      g_bus_get_sync(G_BUS_TYPE_SYSTEM, NULL, &error);
+
+  if (error) {
+    spdlog::error("g_bus_get_sync() failed: {}", error->message);
+    g_error_free(error);
+    connection = nullptr;
+  }
+
+  auto destructor = [](GDBusConnection* connection) {
+      GError *error = nullptr;
+      g_dbus_connection_close_sync(connection, nullptr, &error);
+      if (error) {
+        spdlog::error(
+            "g_bus_connection_close_sync failed(): {}",
+            error->message);
+        g_error_free(error);
+      }
+  };
+
+  return DBus{connection, destructor};
+}
+
+auto getLocks(const DBus& bus, const std::string& inhibitors) -> int {
+  GError *error = nullptr;
+  GUnixFDList* fd_list;
+  int handle;
+
+  auto reply = g_dbus_connection_call_with_unix_fd_list_sync(bus.get(),
+      "org.freedesktop.login1",
+      "/org/freedesktop/login1",
+      "org.freedesktop.login1.Manager",
+      "Inhibit",
+      g_variant_new(
+          "(ssss)",
+          inhibitors.c_str(),
+          "waybar",
+          "Asked by user",
+          "block"),
+      G_VARIANT_TYPE("(h)"),
+      G_DBUS_CALL_FLAGS_NONE,
+      -1,
+      nullptr,
+      &fd_list,
+      nullptr,
+      &error);
+  if (error) {
+    spdlog::error(
+        "g_dbus_connection_call_with_unix_fd_list_sync() failed: {}",
+        error->message);
+    g_error_free(error);
+    handle = -1;
+  } else {
+    gint index;
+    g_variant_get(reply, "(h)", &index);
+    g_variant_unref(reply);
+    handle = g_unix_fd_list_get(fd_list, index, nullptr);
+    g_object_unref(fd_list);
+  }
+
+  return handle;
+}
+
+auto checkInhibitor(const std::string& inhibitor) -> const std::string& {
+  static const auto inhibitors = std::array{
+      "idle",
+      "shutdown",
+      "sleep",
+      "handle-power-key",
+      "handle-suspend-key",
+      "handle-hibernate-key",
+      "handle-lid-switch"
+  };
+
+  if (std::find(inhibitors.begin(), inhibitors.end(), inhibitor)
+          == inhibitors.end()) {
+    throw std::runtime_error("invalid logind inhibitor " + inhibitor);
+  }
+
+  return inhibitor;
+}
+
+auto getInhibitors(const Json::Value& config) -> std::string {
+  std::string inhibitors = "idle";
+
+  if (config["what"].empty()) {
+    return inhibitors;
+  }
+
+  if (config["what"].isString()) {
+    return checkInhibitor(config["what"].asString());
+  }
+
+  if (config["what"].isArray()) {
+    inhibitors = checkInhibitor(config["what"][0].asString());
+    for (decltype(config["what"].size()) i = 1; i < config["what"].size(); ++i) {
+      inhibitors += ":" + checkInhibitor(config["what"][i].asString());
+    }
+    return inhibitors;
+  }
+
+  return inhibitors;
+}
+
+}
+
+namespace waybar::modules {
+
+Inhibitor::Inhibitor(const std::string& id, const Bar& bar,
+                     const Json::Value& config)
+    : ALabel(config, "inhibitor", id, "{status}", true),
+      dbus_(::dbus()),
+      inhibitors_(::getInhibitors(config)) {
+  event_box_.add_events(Gdk::BUTTON_PRESS_MASK);
+  event_box_.signal_button_press_event().connect(
+      sigc::mem_fun(*this, &Inhibitor::handleToggle));
+  dp.emit();
+}
+
+Inhibitor::~Inhibitor() {
+  if (handle_ != -1) {
+    ::close(handle_);
+  }
+}
+
+auto Inhibitor::activated() -> bool {
+  return handle_ != -1;
+}
+
+auto Inhibitor::update() -> void {
+  std::string status_text = activated() ? "activated" : "deactivated";
+
+  label_.get_style_context()->remove_class(
+      activated() ? "deactivated" : "activated");
+  label_.set_markup(
+      fmt::format(format_, fmt::arg("status", status_text),
+      fmt::arg("icon", getIcon(0, status_text))));
+  label_.get_style_context()->add_class(status_text);
+
+  if (tooltipEnabled()) {
+    label_.set_tooltip_text(status_text);
+  }
+
+  return ALabel::update();
+}
+
+auto Inhibitor::handleToggle(GdkEventButton* const& e) -> bool {
+  if (e->button == 1) {
+    if (activated()) {
+      ::close(handle_);
+      handle_ = -1;
+    } else {
+      handle_ = ::getLocks(dbus_, inhibitors_);
+      if (handle_ == -1) {
+        spdlog::error("cannot get inhibitor locks");
+      }
+    }
+  }
+
+  return ALabel::handleToggle(e);
+}
+
+} // waybar::modules