diff -r e59a989d890d -r 060a8cda7f62 libidav/utils.c
--- a/libidav/utils.c	Thu Mar 28 11:19:13 2019 +0100
+++ b/libidav/utils.c	Thu Mar 28 11:54:27 2019 +0100
@@ -824,7 +824,7 @@
 }
 
 
-char* util_hexstr(unsigned char *data, size_t len) {
+char* util_hexstr(const unsigned char *data, size_t len) {
     size_t buflen = 2*len + 4;
     UcxBuffer *buf = ucx_buffer_new(malloc(buflen), buflen + 1, 0);
     for(int i=0;i<len;i++) {