Rewrite add_string_to_logwindow()

Make static, fix formatting, shorten some variable names, use += to add
to variable, accept immutable strings.

xrdp/xrdp_wm.c

@@ -1857,22 +1857,21 @@ xrdp_wm_log_wnd_notify(struct xrdp_bitmap *wnd,
     return 0;
 }
 
-void add_string_to_logwindow(char *msg, struct list *log)
+static void
+add_string_to_logwindow(const char *msg, struct list *log)
 {
-
-    char *new_part_message;
-    char *current_pointer = msg ;
-    int processedlen = 0;
+    const char *new_part_message;
+    const char *current_pointer = msg;
+    int len_done = 0;
 
     do
     {
         new_part_message = g_strndup(current_pointer, LOG_WINDOW_CHAR_PER_LINE);
         g_writeln("%s", new_part_message);
-        list_add_item(log, (long)new_part_message);
-        processedlen = processedlen + g_strlen(new_part_message);
-        current_pointer = current_pointer + g_strlen(new_part_message) ;
-    }
-    while ((processedlen < g_strlen(msg)) && (processedlen < DEFAULT_STRING_LEN));
+        list_add_item(log, (tintptr) new_part_message);
+        len_done += g_strlen(new_part_message);
+        current_pointer += g_strlen(new_part_message);
+    } while ((len_done < g_strlen(msg)) && (len_done < DEFAULT_STRING_LEN));
 }
 
 /*****************************************************************************/