-__attribute__ ((format (printf, 5, 6)));
-extern int log_register_commands(struct command_context_s *cmd_ctx);
-extern int log_init(struct command_context_s *cmd_ctx);
-extern int set_log_output(struct command_context_s *cmd_ctx, FILE *output);
-extern void keep_alive(void);
-extern void kept_alive(void);
-extern void alive_sleep(int ms);
-extern void busy_sleep(int ms);
-
-typedef void (*log_callback_fn)(void *priv, const char *file, int line,
+__attribute__ ((format (PRINTF_ATTRIBUTE_FORMAT, 5, 6)));
+
+/**
+ * Initialize logging module. Call during program startup.
+ */
+void log_init(void);
+int set_log_output(struct command_context *cmd_ctx, FILE *output);
+
+int log_register_commands(struct command_context *cmd_ctx);
+
+void keep_alive(void);
+void kept_alive(void);
+
+void alive_sleep(uint64_t ms);
+void busy_sleep(uint64_t ms);
+
+typedef void (*log_callback_fn)(void *priv, const char *file, unsigned line,