diff --git a/include/osmocom/core/logging.h b/include/osmocom/core/logging.h
index 76be100..bbaef45 100644
--- a/include/osmocom/core/logging.h
+++ b/include/osmocom/core/logging.h
@@ -31,7 +31,7 @@
 void osmo_vlogp(int subsys, int level, char *file, int line,
 		int cont, const char *format, va_list ap);
 
-void logp(int subsys, char *file, int line, int cont, const char *format, ...) __attribute__ ((format (printf, 5, 6)));
+void logp(int subsys, const char *file, int line, int cont, const char *format, ...) __attribute__ ((format (printf, 5, 6)));
 
 /*! \brief Log a new message through the Osmocom logging framework
  *  \param[in] ss logging subsystem (e.g. \ref DLGLOBAL)
@@ -165,7 +165,7 @@
 };
 
 /* use the above macros */
-void logp2(int subsys, unsigned int level, char *file,
+void logp2(int subsys, unsigned int level, const char *file,
 	   int line, int cont, const char *format, ...)
 				__attribute__ ((format (printf, 6, 7)));
 int log_init(const struct log_info *inf, void *talloc_ctx);