From: Kevin Day <Kevin@kevux.org>
Date: Fri, 9 Oct 2026 00:27:34 +0000 (-0500)
Subject: Update: Ensure f_fll_id_t.name is always NULL terminated.
X-Git-Url: https://git.kevux.org/?a=commitdiff_plain;h=8b2791ed56bf818ea47bf82f66b819b6d535fabc;p=fll

Update: Ensure f_fll_id_t.name is always NULL terminated.

Set the normal length of `f_fll_id_name_length_d` to 63.
Then have the actual max length remain at 64 via newly added `f_fll_id_name_max_length_d`.

The `f_fll_id_name_length_d` is only used for comparisons now.
The `f_fll_id_name_max_length_d` is used on the structure.
This should prevent **API** and **ABI** breakage.

Add missing close parenthesis in documentation comment.
---

diff --git a/level_0/f_type/c/type/fll.h b/level_0/f_type/c/type/fll.h
index 26de31930..3e333a0a6 100644
--- a/level_0/f_type/c/type/fll.h
+++ b/level_0/f_type/c/type/fll.h
@@ -22,12 +22,12 @@ extern "C" {
  * This was originally designed for FSS (Featureless Settings Specification) but has been expanded to be used by the entire project.
  *
  * An FLL Identifier consists of two parts:
- * 1) A 64-byte long string representing a machine-name for the type.
+ * 1) A 64-byte long string representing a machine-name for the type, where the last byte (the 64th byte) must always be NULL.
  * 2) A 16-bit digit representing 2^16 possible type classifications, which is representeed by 4 hexadecial 1-byte strings for text.
  *
  * For example "fss-1234" is a valid type such that:
  * 1) name: "fss".
- * 2) type: "1234", (or 0x1 in binary.
+ * 2) type: "1234", (or 0x1 in binary).
  *
  * UTF-8 codes are available, but one must consider that 1 4-byte characte still takes up 4-bytes.
  * Therefore for all 4-byte UTF-8 characters, there is a maximum of 16 characters available.
@@ -40,16 +40,20 @@ extern "C" {
  *
  * The name must only be "word" characters (therefore "-" is not allowed).
  *
+ * The f_fll_id_name_length_d defines the length of non-NULL characters and the f_fll_id_name_max_length_d must always be 1 byte longer than f_fll_id_name_length_d.
+ * This allows for the f_fll_id_t.name to be guaranteed to always be a NULL terminated when properly managed.
+ *
  * Properties:
  *   - name: The string representing the name of the FLL Identifier (This is not a NULL terminated string).
  *   - type: The code representing the type of the Identifier.
  *   - used: A representation of how many bytes in name are in used (if 0, then there is no name, thus this can be seen as not a valid identifier).
  */
 #ifndef _di_f_fll_id_t_
-  #define f_fll_id_name_length_d 64
+  #define f_fll_id_name_length_d     63
+  #define f_fll_id_name_max_length_d (f_fll_id_name_length_d + 1)
 
   typedef struct {
-    char name[f_fll_id_name_length_d];
+    char name[f_fll_id_name_max_length_d];
 
     uint16_t type;
     uint8_t used;