From 304165e407faec47f18e7ab9f98ddc1300e74710 Mon Sep 17 00:00:00 2001
From: Jaby <Jaby>
Date: Sun, 22 Jan 2023 14:37:09 +0100
Subject: [PATCH] Encode word size into OverlayLBA structure

---
 include/PSX/Overlay/overlay.hpp               |  4 +--
 .../psxcdgen_ex/src/types/overlay/mod.rs      | 28 +++++++++++++------
 2 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/include/PSX/Overlay/overlay.hpp b/include/PSX/Overlay/overlay.hpp
index 8e3f6356..1903782a 100644
--- a/include/PSX/Overlay/overlay.hpp
+++ b/include/PSX/Overlay/overlay.hpp
@@ -5,13 +5,13 @@
 namespace JabyEngine {
     struct __attribute__((packed)) OverlayHeader {
         void   (*execute)();
-        uint16_t lba_size;
+        uint16_t lba_size; //< The size of the OverlayLBA section
     };
 
     // Maybe encode attributes like "isLZ4" into size parameter
     struct __attribute__((packed)) OverlayLBA {
         uint16_t lba;
-        uint16_t size;
+        uint16_t size_words;
     };
 }
 #endif //!__JABYENGINE_OVERLAY__HPP__
\ No newline at end of file
diff --git a/src/Tools/psxcdgen_ex/src/types/overlay/mod.rs b/src/Tools/psxcdgen_ex/src/types/overlay/mod.rs
index c1d46a23..8a77014b 100644
--- a/src/Tools/psxcdgen_ex/src/types/overlay/mod.rs
+++ b/src/Tools/psxcdgen_ex/src/types/overlay/mod.rs
@@ -20,17 +20,27 @@ impl OverlayHeader {
 
 #[repr(packed)]
 struct LBAEntry {
-    lba:     u16,
-    sectors: u16,
+    lba:        u16,
+    size_words: u16,
 }
 
 impl LBAEntry {
-    pub fn write_entry(&mut self, lba: u16, sectors: u16) {
-        let lba     = lba.to_le_bytes();
-        let sectors = sectors.to_le_bytes();
+    pub fn write_entry(&mut self, lba: u16, mut size_bytes: usize) -> Result<(), Error> {
+        const WORD_SIZE:usize = std::mem::size_of::<u32>();
 
-        self.lba     = u16::from_ne_bytes(lba);
-        self.sectors = u16::from_ne_bytes(sectors);
+        size_bytes = (size_bytes + (WORD_SIZE - 1))/WORD_SIZE;
+
+        if (size_bytes as u16) as usize != size_bytes {
+            return Err(Error::from_text(format!("{} words can not be incoded into 16bit", size_bytes)));
+        }
+
+        let lba        = lba.to_le_bytes();
+        let size_bytes = (size_bytes as u16).to_le_bytes();
+
+        self.lba        = u16::from_ne_bytes(lba);
+        self.size_words = u16::from_ne_bytes(size_bytes);
+
+        Ok(())
     }
 }
 
@@ -49,13 +59,13 @@ pub fn update_content(content: &mut Vec<u8>, lba_names: &LBANameVec, file_map: &
     let mut idx = 0;
     for lba_name in lba_names {
         if let Some(file) = file_map.get(lba_name) {
-            let (lba, sector_count) = (file.borrow().get_track_rel_lba(), length_func(&Layout::File(file.clone())).sectors);
+            let (lba, bytes) = (file.borrow().get_track_rel_lba(), length_func(&Layout::File(file.clone())).bytes);            
 
             if idx >= lba_count {
                 return Err(Error::from_text(format!("Trying to write more LBAs then there is space!")));
             }
 
-            lba_header[idx].write_entry(lba as u16, sector_count as u16);
+            lba_header[idx].write_entry(lba as u16, bytes.ok_or(Error::from_text(format!("{} does not contain a size!", lba_name)))?)?;
             idx += 1;
         }