diff --git a/configure.ac b/configure.ac
index e3ccdf34..006d0f45 100644
--- a/configure.ac
+++ b/configure.ac
@@ -75,6 +75,7 @@ AC_CHECK_FUNC([strtok_r],, AC_MSG_ERROR("Could not find strtok_r"))
 AC_CHECK_FUNC([flock],,    AC_MSG_ERROR("Could not find flock"))
 AC_CHECK_FUNC([ftruncate],,AC_MSG_ERROR("Could not find ftruncate"))
 AC_CHECK_FUNC([fcntl],,    AC_MSG_ERROR("Could not find fcntl"))
+AC_CHECK_FUNC([setlocale],,AC_MSG_ERROR("Could not find setlocale"))
 
 dnl ---------------------------------------------------------------------
 dnl Check dependencies
diff --git a/include/helper.h b/include/helper.h
index 42c71297..fafce9ac 100644
--- a/include/helper.h
+++ b/include/helper.h
@@ -85,6 +85,7 @@ int find_arg_str ( const char * const key, char** val );
  */
 int find_arg ( const char * const key );
 
+
 /**
  * @param tokens  List of (input) tokens to match.
  * @param input   The entry to match against.
@@ -93,8 +94,7 @@ int find_arg ( const char * const key );
  *
  * @returns TRUE when matches, FALSE otherwise
  */
-int token_match ( GRegex **tokens, const char *input );
-
+int token_match ( GRegex * const *tokens, const char *input );
 /**
  * @param cmd The command to execute.
  *
diff --git a/include/scrollbar.h b/include/scrollbar.h
index d3839fef..71002676 100644
--- a/include/scrollbar.h
+++ b/include/scrollbar.h
@@ -77,7 +77,7 @@ void scrollbar_draw ( scrollbar *sb, cairo_t *draw );
  *
  * Calculate the position of the click relative to the max value of bar
  */
-unsigned int scrollbar_clicked ( scrollbar *sb, int y );
+unsigned int scrollbar_clicked ( const scrollbar *sb, int y );
 
 /**
  * @param sb scrollbar object
diff --git a/include/textbox.h b/include/textbox.h
index 3109f577..6e69b18c 100644
--- a/include/textbox.h
+++ b/include/textbox.h
@@ -39,16 +39,16 @@ typedef struct
 
 typedef enum
 {
-    TB_AUTOHEIGHT = 1 << 0,
-    TB_AUTOWIDTH  = 1 << 1,
-    TB_LEFT       = 1 << 16,
-    TB_RIGHT      = 1 << 17,
-    TB_CENTER     = 1 << 18,
-    TB_EDITABLE   = 1 << 19,
-    TB_MARKUP     = 1 << 20,
-    TB_WRAP       = 1 << 21,
-    TB_PASSWORD   = 1 << 22,
-    TB_INDICATOR  = 1 << 23,
+    TB_AUTOHEIGHT    = 1 << 0,
+        TB_AUTOWIDTH = 1 << 1,
+        TB_LEFT      = 1 << 16,
+        TB_RIGHT     = 1 << 17,
+        TB_CENTER    = 1 << 18,
+        TB_EDITABLE  = 1 << 19,
+        TB_MARKUP    = 1 << 20,
+        TB_WRAP      = 1 << 21,
+        TB_PASSWORD  = 1 << 22,
+        TB_INDICATOR = 1 << 23,
 } TextboxFlags;
 
 typedef enum
@@ -113,7 +113,7 @@ int textbox_keybinding ( textbox *tb, KeyBindingAction action );
  * The text should be one insert from a keypress..  the first gunichar is validated to be (or not) control
  * return TRUE if inserted
  */
-gboolean textbox_append_char ( textbox *tb, char *pad, int pad_len );
+gboolean textbox_append_char ( textbox *tb, const char *pad, const int pad_len );
 
 /**
  * @param tb  Handle to the textbox
@@ -138,7 +138,7 @@ void textbox_cursor ( textbox *tb, int pos );
  *
  * Insert the string str at position pos.
  */
-void textbox_insert ( textbox *tb, int pos, char *str, int slen );
+void textbox_insert ( textbox *tb, const int pos, const char *str, const int slen );
 
 /**
  * Setup the cached fonts. This is required to do
@@ -159,7 +159,7 @@ void textbox_cleanup ( void );
  *
  * @returns the height of the textbox in pixels.
  */
-int textbox_get_height ( textbox *tb );
+int textbox_get_height ( const textbox *tb );
 
 /**
  * @param tb Handle to the textbox
@@ -168,7 +168,7 @@ int textbox_get_height ( textbox *tb );
  *
  * @returns the width of the textbox in pixels.
  */
-int textbox_get_width ( textbox *tb );
+int textbox_get_width ( const textbox *tb );
 
 /**
  * @param tb Handle to the textbox
@@ -177,7 +177,7 @@ int textbox_get_width ( textbox *tb );
  *
  * @returns the height of the string in pixels.
  */
-int textbox_get_font_height ( textbox *tb );
+int textbox_get_font_height ( const textbox *tb );
 
 /**
  * @param tb Handle to the textbox
@@ -186,7 +186,7 @@ int textbox_get_font_height ( textbox *tb );
  *
  * @returns the width of the string in pixels.
  */
-int textbox_get_font_width ( textbox *tb );
+int textbox_get_font_width ( const textbox *tb );
 
 /**
  * Estimate the width of a character.
@@ -239,6 +239,11 @@ void textbox_set_pango_attributes ( textbox *tb, PangoAttrList *list );
 
 PangoAttrList *textbox_get_pango_attributes ( textbox *tb );
 
-const char *textbox_get_visible_text ( textbox *tb );
+/**
+ * @param tb Handle to the textbox
+ *
+ * @returns the visible text.
+ */
+const char *textbox_get_visible_text ( const textbox *tb );
 /*@}*/
 #endif //ROFI_TEXTBOX_H
diff --git a/source/dialogs/ssh.c b/source/dialogs/ssh.c
index 397893dc..f11ba3a1 100644
--- a/source/dialogs/ssh.c
+++ b/source/dialogs/ssh.c
@@ -198,7 +198,7 @@ static char **read_hosts_file ( char ** retv, unsigned int *length )
         // Reading one line per time.
         while ( getline ( &buffer, &buffer_length, fd ) > 0 ) {
             // Evaluate one line.
-            unsigned int index  = 0, ti = 0;
+            unsigned int index = 0, ti = 0;
             char         *token = buffer;
 
             // Tokenize it.
diff --git a/source/helper.c b/source/helper.c
index f74203d1..a0a9902b 100644
--- a/source/helper.c
+++ b/source/helper.c
@@ -204,7 +204,7 @@ GRegex **tokenize ( const char *input, int case_sensitive )
     }
 
     char   *saveptr = NULL, *token;
-    GRegex **retv   = NULL;
+    GRegex **retv = NULL;
     if ( !config.tokenize ) {
         retv    = g_malloc0 ( sizeof ( GRegex* ) * 2 );
         retv[0] = (GRegex *) create_regex ( input, case_sensitive );
@@ -362,13 +362,14 @@ PangoAttrList *token_match_get_pango_attr ( GRegex **tokens, const char *input,
     return retv;
 }
 
-int token_match ( GRegex **tokens, const char *input )
+
+int token_match ( GRegex * const *tokens, const char *input )
 {
     int match = 1;
     // Do a tokenized match.
     if ( tokens ) {
         for ( int j = 0; match && tokens[j]; j++ ) {
-            match = g_regex_match ( (GRegex *) tokens[j], input, 0, NULL );
+            match = g_regex_match ( (const GRegex *) tokens[j], input, 0, NULL );
         }
     }
     return match;
diff --git a/source/rofi.c b/source/rofi.c
index 1f7f290f..cd0fc842 100644
--- a/source/rofi.c
+++ b/source/rofi.c
@@ -73,9 +73,9 @@ struct xkb_stuff xkb        = {
     .keymap         = NULL,
     .state          = NULL,
     .compose        = {
-        .table = NULL,
-        .state = NULL
-    }
+                       .table = NULL,
+                       .state = NULL
+}
 };
 char             *config_path = NULL;
 // Array of modi.
@@ -466,22 +466,22 @@ static gboolean main_loop_x11_event_handler ( xcb_generic_event_t *ev, G_GNUC_UN
             xkb.state  = xkb_x11_state_new_from_device ( xkb.keymap, xcb->connection, xkb.device_id );
             break;
         case XCB_XKB_STATE_NOTIFY:
-        {
-            xcb_xkb_state_notify_event_t *ksne = (xcb_xkb_state_notify_event_t *) ev;
-            guint                        modmask;
-            xkb_state_update_mask ( xkb.state,
-                                    ksne->baseMods,
-                                    ksne->latchedMods,
-                                    ksne->lockedMods,
-                                    ksne->baseGroup,
-                                    ksne->latchedGroup,
-                                    ksne->lockedGroup );
-            modmask = x11_get_current_mask ( &xkb );
-            if ( modmask == 0 ) {
-                abe_trigger_release ( );
+            {
+                xcb_xkb_state_notify_event_t *ksne = (xcb_xkb_state_notify_event_t *) ev;
+                guint                        modmask;
+                xkb_state_update_mask ( xkb.state,
+                                        ksne->baseMods,
+                                        ksne->latchedMods,
+                                        ksne->lockedMods,
+                                        ksne->baseGroup,
+                                        ksne->latchedGroup,
+                                        ksne->lockedGroup );
+                modmask = x11_get_current_mask ( &xkb );
+                if ( modmask == 0 ) {
+                    abe_trigger_release ( );
+                }
+                break;
             }
-            break;
-        }
         }
         return G_SOURCE_CONTINUE;
     }
diff --git a/source/scrollbar.c b/source/scrollbar.c
index 84e3219b..1da6f689 100644
--- a/source/scrollbar.c
+++ b/source/scrollbar.c
@@ -107,7 +107,7 @@ void scrollbar_resize ( scrollbar *sb, int w, int h )
         }
     }
 }
-unsigned int scrollbar_clicked ( scrollbar *sb, int y )
+unsigned int scrollbar_clicked ( const scrollbar *sb, int y )
 {
     if ( sb != NULL ) {
         if ( y >= sb->widget.y && y < ( sb->widget.y + sb->widget.h ) ) {
diff --git a/source/textbox.c b/source/textbox.c
index 0422b940..ee2898c4 100644
--- a/source/textbox.c
+++ b/source/textbox.c
@@ -164,7 +164,7 @@ static void __textbox_update_pango_text ( textbox *tb )
         pango_layout_set_text ( tb->layout, tb->text, -1 );
     }
 }
-const char *textbox_get_visible_text ( textbox *tb )
+const char *textbox_get_visible_text ( const textbox *tb )
 {
     return pango_layout_get_text ( tb->layout );
 }
@@ -464,7 +464,7 @@ void textbox_cursor_end ( textbox *tb )
 }
 
 // insert text
-void textbox_insert ( textbox *tb, int char_pos, char *str, int slen )
+void textbox_insert ( textbox *tb, const int char_pos, const char *str, const int slen )
 {
     char *c  = g_utf8_offset_to_pointer ( tb->text, char_pos );
     int  pos = c - tb->text;
@@ -634,7 +634,7 @@ int textbox_keybinding ( textbox *tb, KeyBindingAction action )
     }
 }
 
-gboolean textbox_append_char ( textbox *tb, char *pad, int pad_len )
+gboolean textbox_append_char ( textbox *tb, const char *pad, const int pad_len )
 {
     if ( !( tb->flags & TB_EDITABLE ) ) {
         return FALSE;
@@ -712,25 +712,25 @@ void textbox_cleanup ( void )
     }
 }
 
-int textbox_get_width ( textbox *tb )
+int textbox_get_width ( const textbox *tb )
 {
     unsigned int offset = ( tb->flags & TB_INDICATOR ) ? DOT_OFFSET : 0;
     return textbox_get_font_width ( tb ) + 2 * SIDE_MARGIN + offset;
 }
 
-int textbox_get_height ( textbox *tb )
+int textbox_get_height ( const textbox *tb )
 {
     return textbox_get_font_height ( tb ) + 2 * SIDE_MARGIN;
 }
 
-int textbox_get_font_height ( textbox *tb )
+int textbox_get_font_height ( const textbox *tb )
 {
     int height;
     pango_layout_get_pixel_size ( tb->layout, NULL, &height );
     return height;
 }
 
-int textbox_get_font_width ( textbox *tb )
+int textbox_get_font_width ( const textbox *tb )
 {
     int width;
     pango_layout_get_pixel_size ( tb->layout, &width, NULL );