[gnome-applets/wip/muktupavels/werror] multiload: fix -Wdiscarded-qualifiers warnings

[Alberts Muktupāvels <muktupavels src gnome org>]

commit e7502fcda977163b4d706e39b08149ed8877427b
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Sat Apr 4 20:56:52 2020 +0300

    multiload: fix -Wdiscarded-qualifiers warnings

 gnome-applets/multiload/properties.c | 166 ++++++++++++++++++++++++-----------
 1 file changed, 113 insertions(+), 53 deletions(-)
---
diff --git a/gnome-applets/multiload/properties.c b/gnome-applets/multiload/properties.c
index 96cf23882..283d30861 100644
--- a/gnome-applets/multiload/properties.c
+++ b/gnome-applets/multiload/properties.c
@@ -25,6 +25,36 @@
 #define HIG_IDENTATION         "    "
 #define NEVER_SENSITIVE                "never_sensitive"
 
+typedef struct
+{
+  MultiloadApplet *ma;
+  const char      *key;
+  int              prop_type;
+} CallbackData;
+
+static CallbackData *
+callback_data_new (MultiloadApplet *ma,
+                   const char      *key,
+                   int              prop_type)
+{
+  CallbackData *data;
+
+  data = g_new0 (CallbackData, 1);
+
+  data->ma = ma;
+  data->key = key;
+  data->prop_type = prop_type;
+
+  return data;
+}
+
+static void
+callback_data_free (gpointer  data,
+                    GClosure *closure)
+{
+  g_free (data);
+}
+
 /* set sensitive and setup NEVER_SENSITIVE appropriately */
 static void
 hard_set_sensitive (GtkWidget *w, gboolean sensitivity)
@@ -84,16 +114,17 @@ properties_close_cb (GtkWidget *widget, gint arg, MultiloadApplet *ma)
 }
 
 static void
-property_toggled_cb(GtkWidget *widget, gpointer name)
+property_toggled_cb (GtkWidget    *widget,
+                     CallbackData *data)
 {
        MultiloadApplet *ma;
        gint prop_type, i;
        gboolean active = gtk_toggle_button_get_active(GTK_TOGGLE_BUTTON(widget));
-       
-       ma = g_object_get_data(G_OBJECT(widget), "MultiloadApplet");
-       prop_type = GPOINTER_TO_INT(g_object_get_data(G_OBJECT(widget), "prop_type"));
 
-       g_settings_set_boolean (ma->settings, (gchar *)name, active);
+       ma = data->ma;
+       prop_type = data->prop_type;
+
+       g_settings_set_boolean (ma->settings, data->key, active);
 
        if (active)
        {
@@ -115,16 +146,17 @@ property_toggled_cb(GtkWidget *widget, gpointer name)
 }
 
 static void
-spin_button_changed_cb(GtkWidget *widget, gpointer name)
+spin_button_changed_cb (GtkWidget    *widget,
+                        CallbackData *data)
 {
        MultiloadApplet *ma;
        gint value, prop_type, i;
-       
-       ma = g_object_get_data(G_OBJECT(widget), "MultiloadApplet");
-       prop_type = GPOINTER_TO_INT(g_object_get_data(G_OBJECT(widget), "prop_type"));
+
+       ma = data->ma;
+       prop_type = data->prop_type;
        value = gtk_spin_button_get_value_as_int(GTK_SPIN_BUTTON(widget));
 
-       g_settings_set_int (ma->settings, (gchar *)name, value);
+       g_settings_set_int (ma->settings, data->key, value);
 
        switch(prop_type)
        {
@@ -182,7 +214,8 @@ add_page(GtkWidget *notebook, gchar *label)
 
 /* save the selected color to GSettings and apply it on the applet */
 static void
-color_picker_set_cb(GtkColorButton *color_picker, gpointer data)
+color_picker_set_cb (GtkColorButton *color_picker,
+                     CallbackData   *data)
 {
        gchar *color_string;
        const gchar *key;
@@ -190,8 +223,8 @@ color_picker_set_cb(GtkColorButton *color_picker, gpointer data)
        GdkRGBA color;
        MultiloadApplet *ma;
 
-       key = (const gchar *) data;
-       ma = g_object_get_data (G_OBJECT (color_picker), "MultiloadApplet");
+       key = data->key;
+       ma = data->ma;
 
        prop_type = 0;
        
@@ -220,7 +253,10 @@ color_picker_set_cb(GtkColorButton *color_picker, gpointer data)
 
 /* create a color selector */
 static void
-add_color_selector(GtkWidget *page, gchar *name, gchar *key, MultiloadApplet *ma)
+add_color_selector (GtkWidget       *page,
+                    const char      *name,
+                    const char      *key,
+                    MultiloadApplet *ma)
 {
        GtkWidget *vbox;
        GtkWidget *label;
@@ -243,12 +279,15 @@ add_color_selector(GtkWidget *page, gchar *name, gchar *key, MultiloadApplet *ma
        gtk_box_pack_start (GTK_BOX (vbox), label, FALSE, FALSE, 0);
        
        gtk_box_pack_start(GTK_BOX(page), vbox, FALSE, FALSE, 0);       
-       
-       g_object_set_data (G_OBJECT (color_picker), "MultiloadApplet", ma);
 
        gtk_color_button_set_rgba (GTK_COLOR_BUTTON (color_picker), &color);
 
-       g_signal_connect(G_OBJECT(color_picker), "color_set", G_CALLBACK(color_picker_set_cb), key);
+       g_signal_connect_data (color_picker,
+                              "color_set",
+                              G_CALLBACK (color_picker_set_cb),
+                              callback_data_new (ma, key, 0),
+                              callback_data_free,
+                              0);
 
        if (!g_settings_is_writable (ma->settings, key))
                hard_set_sensitive (vbox, FALSE);
@@ -317,12 +356,15 @@ fill_properties(GtkWidget *dialog, MultiloadApplet *ma)
        ma->check_boxes[0] = check_box;
        gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(check_box),
                                g_settings_get_boolean (ma->settings, KEY_VIEW_CPULOAD));
-       g_object_set_data(G_OBJECT(check_box), "MultiloadApplet", ma);
-       g_object_set_data(G_OBJECT(check_box), "prop_type", GINT_TO_POINTER(PROP_CPU));
-       g_signal_connect(G_OBJECT(check_box), "toggled",
-                               G_CALLBACK(property_toggled_cb), "view-cpuload");
        gtk_box_pack_start (GTK_BOX (control_hbox), check_box, FALSE, FALSE, 0);
 
+       g_signal_connect_data (check_box,
+                              "toggled",
+                              G_CALLBACK (property_toggled_cb),
+                              callback_data_new (ma, "view-cpuload", PROP_CPU),
+                              callback_data_free,
+                              0);
+
        if (!g_settings_is_writable (ma->settings, KEY_VIEW_CPULOAD))
                hard_set_sensitive (check_box, FALSE);
        
@@ -330,12 +372,15 @@ fill_properties(GtkWidget *dialog, MultiloadApplet *ma)
        ma->check_boxes[1] = check_box;
        gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(check_box),
                                g_settings_get_boolean (ma->settings, KEY_VIEW_MEMLOAD));
-       g_object_set_data(G_OBJECT(check_box), "MultiloadApplet", ma);
-       g_object_set_data(G_OBJECT(check_box), "prop_type", GINT_TO_POINTER(PROP_MEM));
-       g_signal_connect(G_OBJECT(check_box), "toggled",
-                               G_CALLBACK(property_toggled_cb), "view-memload");
        gtk_box_pack_start (GTK_BOX (control_hbox), check_box, FALSE, FALSE, 0);
 
+       g_signal_connect_data (check_box,
+                              "toggled",
+                              G_CALLBACK (property_toggled_cb),
+                              callback_data_new (ma, "view-memload", PROP_MEM),
+                              callback_data_free,
+                              0);
+
        if (!g_settings_is_writable (ma->settings, KEY_VIEW_MEMLOAD))
                hard_set_sensitive (check_box, FALSE);
        
@@ -343,12 +388,15 @@ fill_properties(GtkWidget *dialog, MultiloadApplet *ma)
        ma->check_boxes[2] = check_box;
        gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(check_box),
                                g_settings_get_boolean (ma->settings, KEY_VIEW_NETLOAD2));
-       g_object_set_data(G_OBJECT(check_box), "MultiloadApplet", ma);
-       g_object_set_data(G_OBJECT(check_box), "prop_type", GINT_TO_POINTER(PROP_NET));
-       g_signal_connect(G_OBJECT(check_box), "toggled",
-                               G_CALLBACK(property_toggled_cb), "view-netload2");
        gtk_box_pack_start (GTK_BOX (control_hbox), check_box, FALSE, FALSE, 0);
 
+       g_signal_connect_data (check_box,
+                              "toggled",
+                              G_CALLBACK (property_toggled_cb),
+                              callback_data_new (ma, "view-netload2", PROP_NET),
+                              callback_data_free,
+                              0);
+
        if (!g_settings_is_writable (ma->settings, KEY_VIEW_NETLOAD2))
                hard_set_sensitive (check_box, FALSE);
 
@@ -356,12 +404,15 @@ fill_properties(GtkWidget *dialog, MultiloadApplet *ma)
        ma->check_boxes[3] = check_box;
        gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(check_box),
                                g_settings_get_boolean (ma->settings, KEY_VIEW_SWAPLOAD));
-       g_object_set_data(G_OBJECT(check_box), "MultiloadApplet", ma);
-       g_object_set_data(G_OBJECT(check_box), "prop_type", GINT_TO_POINTER(PROP_SWAP));
-       g_signal_connect(G_OBJECT(check_box), "toggled",
-                               G_CALLBACK(property_toggled_cb), "view-swapload");
        gtk_box_pack_start (GTK_BOX (control_hbox), check_box, FALSE, FALSE, 0);
 
+       g_signal_connect_data (check_box,
+                              "toggled",
+                              G_CALLBACK (property_toggled_cb),
+                              callback_data_new (ma, "view-swapload", PROP_SWAP),
+                              callback_data_free,
+                              0);
+
        if (!g_settings_is_writable (ma->settings, KEY_VIEW_SWAPLOAD))
                hard_set_sensitive (check_box, FALSE);
 
@@ -369,12 +420,15 @@ fill_properties(GtkWidget *dialog, MultiloadApplet *ma)
        ma->check_boxes[4] = check_box; 
        gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(check_box),
                                g_settings_get_boolean (ma->settings, KEY_VIEW_LOADAVG));
-       g_object_set_data(G_OBJECT(check_box), "MultiloadApplet", ma);
-       g_object_set_data(G_OBJECT(check_box), "prop_type", GINT_TO_POINTER(PROP_AVG));
-       g_signal_connect(G_OBJECT(check_box), "toggled",
-                               G_CALLBACK(property_toggled_cb), "view-loadavg");
        gtk_box_pack_start(GTK_BOX(control_hbox), check_box, FALSE, FALSE, 0);
 
+       g_signal_connect_data (check_box,
+                              "toggled",
+                              G_CALLBACK (property_toggled_cb),
+                              callback_data_new (ma, "view-loadavg", PROP_AVG),
+                              callback_data_free,
+                              0);
+
        if (!g_settings_is_writable (ma->settings, KEY_VIEW_LOADAVG))
                hard_set_sensitive (check_box, FALSE);
 
@@ -382,13 +436,15 @@ fill_properties(GtkWidget *dialog, MultiloadApplet *ma)
        ma->check_boxes[5] = check_box;
        gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (check_box),
                        g_settings_get_boolean (ma->settings, KEY_VIEW_DISKLOAD));
-       g_object_set_data (G_OBJECT (check_box), "MultiloadApplet", ma);
-       g_object_set_data (G_OBJECT (check_box), "prop_type",
-                       GINT_TO_POINTER (PROP_DISK));
-       g_signal_connect (G_OBJECT (check_box), "toggled",
-                       G_CALLBACK (property_toggled_cb), "view-diskload");
        gtk_box_pack_start (GTK_BOX (control_hbox), check_box, FALSE, FALSE, 0);
 
+       g_signal_connect_data (check_box,
+                              "toggled",
+                              G_CALLBACK (property_toggled_cb),
+                              callback_data_new (ma, "view-diskload", PROP_DISK),
+                              callback_data_free,
+                              0);
+
        category_vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 6);
        gtk_box_pack_start (GTK_BOX (categories_vbox), category_vbox, TRUE, TRUE, 0);
        gtk_widget_show (category_vbox);
@@ -439,14 +495,16 @@ fill_properties(GtkWidget *dialog, MultiloadApplet *ma)
                          
        spin_button = gtk_spin_button_new_with_range(10, 1000, 5);
        gtk_label_set_mnemonic_widget (GTK_LABEL (label), spin_button);
-       g_object_set_data(G_OBJECT(spin_button), "MultiloadApplet", ma);
-       g_object_set_data(G_OBJECT(spin_button), "prop_type",
-                               GINT_TO_POINTER(PROP_SIZE));
        gtk_spin_button_set_value(GTK_SPIN_BUTTON(spin_button),
                                (gdouble)g_settings_get_int (ma->settings, KEY_SIZE));
-       g_signal_connect(G_OBJECT(spin_button), "value_changed",
-                               G_CALLBACK(spin_button_changed_cb), "size");
-       
+
+       g_signal_connect_data (spin_button,
+                              "value_changed",
+                              G_CALLBACK (spin_button_changed_cb),
+                              callback_data_new (ma, "size", PROP_SIZE),
+                              callback_data_free,
+                              0);
+
        if (!g_settings_is_writable (ma->settings, KEY_SIZE)) {
                hard_set_sensitive (label, FALSE);
                hard_set_sensitive (hbox, FALSE);
@@ -474,16 +532,18 @@ fill_properties(GtkWidget *dialog, MultiloadApplet *ma)
        
        spin_button = gtk_spin_button_new_with_range(50, 10000, 50);
        gtk_label_set_mnemonic_widget (GTK_LABEL (label), spin_button);
-       g_object_set_data(G_OBJECT(spin_button), "MultiloadApplet", ma);
-       g_object_set_data(G_OBJECT(spin_button), "prop_type",
-                               GINT_TO_POINTER(PROP_SPEED));
        gtk_spin_button_set_value(GTK_SPIN_BUTTON(spin_button),
                                (gdouble)g_settings_get_int (ma->settings, KEY_SPEED));
-       g_signal_connect(G_OBJECT(spin_button), "value_changed",
-                               G_CALLBACK(spin_button_changed_cb), "speed");
        gtk_size_group_add_widget (spin_size, spin_button);
        gtk_box_pack_start (GTK_BOX (hbox), spin_button, FALSE, FALSE, 0);
 
+       g_signal_connect_data (spin_button,
+                              "value_changed",
+                              G_CALLBACK (spin_button_changed_cb),
+                              callback_data_new (ma, "speed", PROP_SPEED),
+                              callback_data_free,
+                              0);
+
        if (!g_settings_is_writable (ma->settings, KEY_SPEED)) {
                hard_set_sensitive (label, FALSE);
                hard_set_sensitive (hbox, FALSE);