From 2c51ab1fcccc6e94635e0fa61af3c9581027dc67 Mon Sep 17 00:00:00 2001
From: Lucas Schwiderski <lucas@lschwiderski.de>
Date: Tue, 1 Jul 2025 10:49:42 +0200
Subject: [PATCH] sdk: Add name for unknown file header field

---
 lib/sdk/src/binary.rs      | 25 ++++++++++++++++++-------
 lib/sdk/src/bundle/file.rs | 28 ++++++++++++++++++++--------
 2 files changed, 38 insertions(+), 15 deletions(-)

diff --git a/lib/sdk/src/binary.rs b/lib/sdk/src/binary.rs
index 9348e1b..9ce9d23 100644
--- a/lib/sdk/src/binary.rs
+++ b/lib/sdk/src/binary.rs
@@ -44,10 +44,10 @@ impl<T: FromBinary> FromBinary for Vec<T> {
 
 pub mod sync {
     use std::ffi::CStr;
-    use std::io::{self, Read, Seek, SeekFrom};
+    use std::io::{self, Read, Seek, SeekFrom, Write};
 
     use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
-    use color_eyre::eyre::WrapErr;
+    use color_eyre::eyre::{self, WrapErr};
     use color_eyre::{Help, Report, Result, SectionExt};
 
     macro_rules! make_read {
@@ -123,7 +123,7 @@ pub mod sync {
         };
     }
 
-    pub trait ReadExt: ReadBytesExt + Seek {
+    pub trait ReadExt: Read + Seek {
         fn read_u8(&mut self) -> io::Result<u8> {
             ReadBytesExt::read_u8(self)
         }
@@ -131,7 +131,6 @@ pub mod sync {
         make_read!(read_u32, read_u32_le, u32);
         make_read!(read_u64, read_u64_le, u64);
 
-        make_skip!(skip_u8, read_u8, u8);
         make_skip!(skip_u32, read_u32, u32);
 
         // Implementation based on https://en.wikipedia.com/wiki/LEB128
@@ -181,9 +180,17 @@ pub mod sync {
                 res
             }
         }
+
+        fn read_bool(&mut self) -> Result<bool> {
+            match ReadExt::read_u8(self)? {
+                0 => Ok(false),
+                1 => Ok(true),
+                v => eyre::bail!("Invalid value for boolean '{}'", v),
+            }
+        }
     }
 
-    pub trait WriteExt: WriteBytesExt + Seek {
+    pub trait WriteExt: Write + Seek {
         fn write_u8(&mut self, val: u8) -> io::Result<()> {
             WriteBytesExt::write_u8(self, val)
         }
@@ -191,6 +198,10 @@ pub mod sync {
         make_write!(write_u32, write_u32_le, u32);
         make_write!(write_u64, write_u64_le, u64);
 
+        fn write_bool(&mut self, val: bool) -> io::Result<()> {
+            WriteBytesExt::write_u8(self, if val { 1 } else { 0 })
+        }
+
         fn write_padding(&mut self) -> io::Result<usize> {
             let pos = self.stream_position()?;
             let size = 16 - (pos % 16) as usize;
@@ -207,8 +218,8 @@ pub mod sync {
         }
     }
 
-    impl<R: ReadBytesExt + Seek + ?Sized> ReadExt for R {}
-    impl<W: WriteBytesExt + Seek + ?Sized> WriteExt for W {}
+    impl<R: Read + Seek + ?Sized> ReadExt for R {}
+    impl<W: Write + Seek + ?Sized> WriteExt for W {}
 
     pub(crate) fn _read_up_to<R>(r: &mut R, buf: &mut Vec<u8>) -> Result<usize>
     where
diff --git a/lib/sdk/src/bundle/file.rs b/lib/sdk/src/bundle/file.rs
index 6d49821..6442f98 100644
--- a/lib/sdk/src/bundle/file.rs
+++ b/lib/sdk/src/bundle/file.rs
@@ -15,17 +15,18 @@ use super::filetype::BundleFileType;
 #[derive(Debug)]
 struct BundleFileHeader {
     variant: u32,
-    unknown_1: u8,
+    external: bool,
     size: usize,
+    unknown_1: u8,
     len_data_file_name: usize,
 }
 
-#[derive(Clone, Debug)]
+#[derive(Clone)]
 pub struct BundleFileVariant {
     property: u32,
     data: Vec<u8>,
     data_file_name: Option<String>,
-    // Seems to be related to whether there is a data path.
+    external: bool,
     unknown_1: u8,
 }
 
@@ -39,6 +40,7 @@ impl BundleFileVariant {
             property: 0,
             data: Vec::new(),
             data_file_name: None,
+            external: false,
             unknown_1: 0,
         }
     }
@@ -63,21 +65,30 @@ impl BundleFileVariant {
         self.data_file_name.as_ref()
     }
 
+    pub fn external(&self) -> bool {
+        self.external
+    }
+
+    pub fn unknown_1(&self) -> u8 {
+        self.unknown_1
+    }
+
     #[tracing::instrument(skip_all)]
     fn read_header<R>(r: &mut R) -> Result<BundleFileHeader>
     where
         R: Read + Seek,
     {
         let variant = r.read_u32()?;
-        let unknown_1 = r.read_u8()?;
+        let external = r.read_bool()?;
         let size = r.read_u32()? as usize;
-        r.skip_u8(1)?;
+        let unknown_1 = r.read_u8()?;
         let len_data_file_name = r.read_u32()? as usize;
 
         Ok(BundleFileHeader {
             size,
-            unknown_1,
+            external,
             variant,
+            unknown_1,
             len_data_file_name,
         })
     }
@@ -88,7 +99,7 @@ impl BundleFileVariant {
         W: Write + Seek,
     {
         w.write_u32(self.property)?;
-        w.write_u8(self.unknown_1)?;
+        w.write_bool(self.external)?;
 
         let len_data_file_name = self.data_file_name.as_ref().map(|s| s.len()).unwrap_or(0);
 
@@ -216,6 +227,7 @@ impl BundleFile {
                 property: header.variant,
                 data,
                 data_file_name,
+                external: header.external,
                 unknown_1: header.unknown_1,
             };
 
@@ -243,7 +255,7 @@ impl BundleFile {
 
         for variant in self.variants.iter() {
             w.write_u32(variant.property())?;
-            w.write_u8(variant.unknown_1)?;
+            w.write_bool(variant.external)?;
 
             let len_data_file_name = variant.data_file_name().map(|s| s.len()).unwrap_or(0);