added function to check whether current jump is first or last

Signed-off-by: Sebastian Ramacher <sebastian+dev@ramacher.at>

zathura.c

@@ -1122,6 +1122,18 @@ position_set_delayed(zathura_t* zathura, double position_x, double position_y)
 }
 
 
+bool
+zathura_jumplist_has_previous(zathura_t* zathura)
+{
+  return girara_list_iterator_has_previous(zathura->jumplist.cur);
+}
+
+bool
+zathura_jumplist_has_has_next(zathura_t* zathura)
+{
+  return girara_list_iterator_has_next(zathura->jumplist.cur);
+}
+
 zathura_jump_t*
 zathura_jumplist_current(zathura_t* zathura)
 {

zathura.h

@@ -334,6 +334,22 @@ void page_widget_set_mode(zathura_t* zathura, unsigned int pages_per_row, unsign
  */
 void statusbar_page_number_update(zathura_t* zathura);
 
+/**
+ * Checks whether current jump has a previous jump
+ *
+ * @param zathura The zathura session
+ * @return true if current jump has a previous jump
+ */
+bool zathura_jumplist_has_previous(zathura_t* zathura);
+
+/**
+ * Checks whether current jump has a next jump
+ *
+ * @param zathura The zathura session
+ * @return true if current jump has a next jump
+ */
+bool zathura_jumplist_has_next(zathura_t* zathura);
+
 /**
  * Return current jump in the jumplist
  *