modules+util: fix actual (potential) memory leaks

include/modules/upower/upower.hpp

@@ -69,7 +69,7 @@ class UPower : public AModule {
   UpDevice *displayDevice;
   guint login1_id;
   GDBusConnection *login1_connection;
-  UPowerTooltip *upower_tooltip;
+  std::unique_ptr<UPowerTooltip> upower_tooltip;
   std::string lastStatus;
   bool showAltText;
   bool upowerRunning;

src/modules/cpu_usage/bsd.cpp

@@ -9,6 +9,7 @@
 #include <cstdlib>  // malloc
 
 #include "modules/cpu_usage.hpp"
+#include "util/scope_guard.hpp"
 
 #if defined(__NetBSD__) || defined(__OpenBSD__)
 #include <sys/sched.h>
@@ -33,6 +34,11 @@ std::vector<std::tuple<size_t, size_t>> waybar::modules::CpuUsage::parseCpuinfo(
   int ncpu = sysconf(_SC_NPROCESSORS_CONF);
   size_t sz = CPUSTATES * (ncpu + 1) * sizeof(pcp_time_t);
   pcp_time_t *cp_time = static_cast<pcp_time_t *>(malloc(sz)), *pcp_time = cp_time;
+  waybar::util::scope_guard cp_time_deleter([cp_time]() {
+    if (cp_time) {
+      free(cp_time);
+    }
+  });
 #if defined(__NetBSD__)
   int mib[] = {
       CTL_KERN,
@@ -97,6 +103,5 @@ std::vector<std::tuple<size_t, size_t>> waybar::modules::CpuUsage::parseCpuinfo(
     }
     cpuinfo.emplace_back(single_cp_time[CP_IDLE], total);
   }
-  free(cp_time);
   return cpuinfo;
 }

src/modules/custom.cpp

@@ -2,6 +2,8 @@
 
 #include <spdlog/spdlog.h>
 
+#include "util/scope_guard.hpp"
+
 waybar::modules::Custom::Custom(const std::string& name, const std::string& id,
                                 const Json::Value& config)
     : ALabel(config, "custom-" + name, id, "{}"),
@@ -57,6 +59,11 @@ void waybar::modules::Custom::continuousWorker() {
   }
   thread_ = [this, cmd] {
     char* buff = nullptr;
+    waybar::util::scope_guard buff_deleter([buff]() {
+      if (buff) {
+        free(buff);
+      }
+    });
     size_t len = 0;
     if (getline(&buff, &len, fp_) == -1) {
       int exit_code = 1;
@@ -90,7 +97,6 @@ void waybar::modules::Custom::continuousWorker() {
       output_ = {0, output};
       dp.emit();
     }
-    free(buff);
   };
 }
 

src/modules/mpris/mpris.cpp

@@ -6,6 +6,8 @@
 #include <sstream>
 #include <string>
 
+#include "util/scope_guard.hpp"
+
 extern "C" {
 #include <playerctl/playerctl.h>
 }
@@ -117,6 +119,11 @@ Mpris::Mpris(const std::string& id, const Json::Value& config)
   }
 
   GError* error = nullptr;
+  waybar::util::scope_guard error_deleter([error]() {
+    if (error) {
+      g_error_free(error);
+    }
+  });
   manager = playerctl_player_manager_new(&error);
   if (error) {
     throw std::runtime_error(fmt::format("unable to create MPRIS client: {}", error->message));
@@ -136,9 +143,7 @@ Mpris::Mpris(const std::string& id, const Json::Value& config)
   } else {
     GList* players = playerctl_list_players(&error);
     if (error) {
-      auto e = fmt::format("unable to list players: {}", error->message);
+      throw std::runtime_error(fmt::format("unable to list players: {}", error->message));
-      g_error_free(error);
-      throw std::runtime_error(e);
     }
 
     for (auto p = players; p != NULL; p = p->next) {
@@ -410,8 +415,7 @@ auto Mpris::onPlayerNameAppeared(PlayerctlPlayerManager* manager, PlayerctlPlaye
     return;
   }
 
-  GError* error = nullptr;
+  mpris->player = playerctl_player_new_from_name(player_name, NULL);
-  mpris->player = playerctl_player_new_from_name(player_name, &error);
   g_object_connect(mpris->player, "signal::play", G_CALLBACK(onPlayerPlay), mpris, "signal::pause",
                    G_CALLBACK(onPlayerPause), mpris, "signal::stop", G_CALLBACK(onPlayerStop),
                    mpris, "signal::stop", G_CALLBACK(onPlayerStop), mpris, "signal::metadata",
@@ -478,6 +482,11 @@ auto Mpris::getPlayerInfo() -> std::optional<PlayerInfo> {
   }
 
   GError* error = nullptr;
+  waybar::util::scope_guard error_deleter([error]() {
+    if (error) {
+      g_error_free(error);
+    }
+  });
 
   char* player_status = nullptr;
   auto player_playback_status = PLAYERCTL_PLAYBACK_STATUS_STOPPED;
@@ -487,9 +496,7 @@ auto Mpris::getPlayerInfo() -> std::optional<PlayerInfo> {
   if (player_name == "playerctld") {
     GList* players = playerctl_list_players(&error);
     if (error) {
-      auto e = fmt::format("unable to list players: {}", error->message);
+      throw std::runtime_error(fmt::format("unable to list players: {}", error->message));
-      g_error_free(error);
-      throw std::runtime_error(e);
     }
     // > get the list of players [..] in order of activity
     // https://github.com/altdesktop/playerctl/blob/b19a71cb9dba635df68d271bd2b3f6a99336a223/playerctl/playerctl-common.c#L248-L249
@@ -568,12 +575,16 @@ auto Mpris::getPlayerInfo() -> std::optional<PlayerInfo> {
 
 errorexit:
   spdlog::error("mpris[{}]: {}", info.name, error->message);
-  g_error_free(error);
   return std::nullopt;
 }
 
 bool Mpris::handleToggle(GdkEventButton* const& e) {
   GError* error = nullptr;
+  waybar::util::scope_guard error_deleter([error]() {
+    if (error) {
+      g_error_free(error);
+    }
+  });
 
   auto info = getPlayerInfo();
   if (!info) return false;
@@ -603,7 +614,6 @@ bool Mpris::handleToggle(GdkEventButton* const& e) {
   if (error) {
     spdlog::error("mpris[{}]: error running builtin on-click action: {}", (*info).name,
                   error->message);
-    g_error_free(error);
     return false;
   }
   return true;

src/modules/upower/upower.cpp

@@ -63,7 +63,7 @@ UPower::UPower(const std::string& id, const Json::Value& config)
   box_.set_has_tooltip(tooltip_enabled);
   if (tooltip_enabled) {
     // Sets the window to use when showing the tooltip
-    upower_tooltip = new UPowerTooltip(iconSize, tooltip_spacing, tooltip_padding);
+    upower_tooltip = std::make_unique<UPowerTooltip>(iconSize, tooltip_spacing, tooltip_padding);
     box_.set_tooltip_window(*upower_tooltip);
     box_.signal_query_tooltip().connect(sigc::mem_fun(*this, &UPower::show_tooltip_callback));
   }
@@ -72,14 +72,13 @@ UPower::UPower(const std::string& id, const Json::Value& config)
                                       G_BUS_NAME_WATCHER_FLAGS_AUTO_START, upowerAppear,
                                       upowerDisappear, this, NULL);
 
-  GError* error = NULL;
+  client = up_client_new_full(NULL, NULL);
-  client = up_client_new_full(NULL, &error);
   if (client == NULL) {
     throw std::runtime_error("Unable to create UPower client!");
   }
 
   // Connect to Login1 PrepareForSleep signal
-  login1_connection = g_bus_get_sync(G_BUS_TYPE_SYSTEM, NULL, &error);
+  login1_connection = g_bus_get_sync(G_BUS_TYPE_SYSTEM, NULL, NULL);
   if (!login1_connection) {
     throw std::runtime_error("Unable to connect to the SYSTEM Bus!...");
   } else {
@@ -99,6 +98,7 @@ UPower::UPower(const std::string& id, const Json::Value& config)
 }
 
 UPower::~UPower() {
+  if (displayDevice != NULL) g_object_unref(displayDevice);
   if (client != NULL) g_object_unref(client);
   if (login1_id > 0) {
     g_dbus_connection_signal_unsubscribe(login1_connection, login1_id);

src/util/prepare_for_sleep.cpp

@@ -7,8 +7,7 @@ namespace {
 class PrepareForSleep {
  private:
   PrepareForSleep() {
-    GError *error = NULL;
+    login1_connection = g_bus_get_sync(G_BUS_TYPE_SYSTEM, NULL, NULL);
-    login1_connection = g_bus_get_sync(G_BUS_TYPE_SYSTEM, NULL, &error);
     if (!login1_connection) {
       spdlog::warn("Unable to connect to the SYSTEM Bus!...");
     } else {