diff --git a/src/logfile.c b/src/logfile.c
index 0af9127..037da33 100644
--- a/src/logfile.c
+++ b/src/logfile.c
@@ -31,7 +31,10 @@ f2b_logfile_open(f2b_logfile_t *file, const char *filename) {
 }
 
 void
-f2b_logfile_close(const f2b_logfile_t *file);
+f2b_logfile_close(const f2b_logfile_t *file) {
+  assert(file != NULL);
+  fclose(file->fd);
+}
 
 bool
 f2b_logfile_rotated(const f2b_logfile_t *file);