1 files changed, 25 insertions, 0 deletions
diff --git a/stringutil.h b/stringutil.h
index ddfebfc..c7cb40d 100644
--- a/stringutil.h
+++ b/stringutil.h
@@ -1,2 +1,27 @@
+/*!
+ * @file
+ * @brief Utilities for string construction
+ */
+
+/*!
+ * @brief Returns hex digit for given integer
+ *
+ * Will return appropriate `char` in range 0-F
+ * for input in range 0-15. Can be abused to
+ * return decimal digits for range 0-9.
+ */
 char nibble_hex(short h);
+
+/*!
+ * @brief Concatenate arbitrary number of strings into
+ * dynamically allocated buffer
+ *
+ * catn_alloc() concats the `n` given strings into a
+ * dynamically allocated and resized buffer and returns
+ * it. This buffer must be cleaned up by `free()` before
+ * it goes out of scope.
+ *
+ * @param n number of strings given as `va_args`
+ * @return pointer to concatenated strings or `NULL` on error.
+ */
 char *catn_alloc(size_t n, ...);