diff -r f9eca4a55911 -r d969e0fe05dc main/xutil.h
--- a/main/xutil.h	Thu Oct 31 22:22:22 2019 +0100
+++ b/main/xutil.h	Fri Nov 01 13:13:14 2019 +0100
@@ -1,8 +1,32 @@
+/**
+ * @file xutil.h
+ * @brief In memory string manipulation.
+ */
+
+
 #ifndef XUTIL_H
 #define	XUTIL_H
 
-char *xmalloc(size_t);
-char *xstrcpy(char *);
-char *xstrcat(char *, char *);
+/**
+ * @brief Safe memory allocation. Abort if not enough.
+ * @param size The amount of memory to allocate.
+ * @return A pointer to the allocated memory.
+ */
+char *xmalloc(size_t size);
+
+/**
+ * @brief Copy string in memory.
+ * @param src The source string to copy.
+ * @return A pointer to the string with the copied string.
+ */
+char *xstrcpy(char *src);
+
+/**
+ * @brief Add data to a string in memory.
+ * @param src The original string.
+ * @param add The string to append to src.
+ * @return A pointer to the combined string.
+ */
+char *xstrcat(char *src, char *add);
 
 #endif