unityfs library usage

1 files changed, 9 insertions, 144 deletions

diff --git a/src/main.rs b/src/main.rs
index 5ba3e3a..69ff519 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,156 +1,21 @@
-pub mod helper;
-
-use anyhow::{Result, anyhow};
-use helper::ReadExt;
-use log::{debug, info};
 use std::{
     env::args,
     fs::File,
-    io::{BufReader, Cursor, Read, Seek, SeekFrom, Write, copy},
+    io::{BufReader, copy},
 };
 
+use assetdebundle::unityfs::UnityFS;
+
 fn main() -> anyhow::Result<()> {
     env_logger::init_from_env("LOG");
-    let mut file = BufReader::new(File::open(args().nth(1).unwrap())?);
-
-    let signature = file.read_cstr()?;
-    let file_version = file.read_u32_be()?;
-    let player_version = file.read_cstr()?;
-    let unity_version = file.read_cstr()?;
-    let size = file.read_u64_be()?;
-    let blockindex_comp_size = file.read_u32_be()?;
-    let blockindex_decomp_size = file.read_u32_be()?;
-    let flags = file.read_u32_be()?;
-
-    let meta_comp_scheme = CompressionScheme::from_flag_num((flags & 0x3f) as u8)
-        .ok_or(anyhow!("unknown block compression"))?;
-    let blockindex_eof = flags & 0x80 != 0;
-    let blockindex_has_directory = flags & 0x40 != 0;
-    let blockindex_need_padding = flags & 0x200 != 0;
-
-    info!("signature={signature:?}");
-    info!("file_version={file_version:?}");
-    info!("player_version={player_version:?}");
-    info!("unity_version={unity_version:?}");
-    debug!("size={size:?}");
-    debug!("meta_comp_size={blockindex_comp_size:?}");
-    debug!("meta_decomp_size={blockindex_decomp_size:?}");
-    debug!("flags={flags:?}");
-    debug!("meta_comp_scheme={meta_comp_scheme:?}");
-    debug!("blockindex_eof={blockindex_eof:?}");
-    debug!("blockindex_has_directory={blockindex_has_directory:?}");
-    debug!("blockindex_need_padding={blockindex_need_padding:?}");
-
-    let mut blockindex = {
-        let restore_position = if blockindex_eof {
-            let pos = file.stream_position()?;
-            file.seek(SeekFrom::End(-(blockindex_comp_size as i64)))?;
-            Some(pos)
-        } else {
-            None
-        };
+    let file = BufReader::new(File::open(args().nth(1).unwrap())?);
+    let mut fs = UnityFS::open(file)?;
 
-        let mut blockindex = vec![0u8; blockindex_comp_size as usize];
-        file.read_exact(&mut blockindex)?;
-
-        if let Some(pos) = restore_position {
-            file.seek(SeekFrom::Start(pos))?;
-        }
-        let blockindex =
-            meta_comp_scheme.decompress(blockindex, blockindex_decomp_size as usize)?;
-        Cursor::new(blockindex)
-    };
-    {
-        // align stream
-        let off = file.stream_position()? % 16;
-        if off != 0 {
-            file.seek_relative(16 - off as i64)?;
-        }
-    }
-
-    blockindex.read_u128_be()?;
-
-    let num_blocks = blockindex.read_u32_be()?;
-    debug!("num_blocks={num_blocks:?}");
-    let mut blocks = Vec::new();
-    for _ in 0..num_blocks {
-        let block_decomp_size = blockindex.read_u32_be()?;
-        let block_comp_size = blockindex.read_u32_be()?;
-        let block_flags = blockindex.read_u16_be()?;
-        let block_comp_scheme = CompressionScheme::from_flag_num((block_flags & 0x3f) as u8)
-            .ok_or(anyhow!("unknown block compression"))?;
-        blocks.push((block_comp_size, block_decomp_size, block_comp_scheme))
-    }
-
-    let num_nodes = blockindex.read_u32_be()?;
-    debug!("num_nodes={num_nodes:?}");
-    let mut nodes = Vec::new();
-    for _ in 0..num_nodes {
-        let offset = blockindex.read_u64_be()?;
-        let size = blockindex.read_u64_be()?;
-        let status = blockindex.read_u32_be()?;
-        let name = blockindex.read_cstr()?;
-        info!("found node {name:?} (offset={offset}, size={size}, status={status})");
-        nodes.push((offset, size, status, name))
-    }
-
-    let mut storage = Vec::new();
-    for (comp_size, decomp_size, comp_scheme) in blocks {
-        let mut comp_buf = vec![0u8; comp_size as usize];
-        file.read_exact(&mut comp_buf)?;
-        let decomp_buf = comp_scheme.decompress(comp_buf, decomp_size as usize)?;
-        assert_eq!(decomp_size, decomp_buf.len() as u32);
-        storage.extend_from_slice(&decomp_buf);
-    }
-    let mut storage = Cursor::new(storage);
-
-    for (offset, size, _status, name) in nodes {
-        storage.seek(SeekFrom::Start(offset))?;
-        info!("extracting {name:?}");
-        let mut file = File::create(format!("/tmp/{}", name))?;
-        copy(&mut (&mut storage).take(size), &mut file)?;
+    for node in fs.nodes().to_vec() {
+        let mut reader = fs.read(&node)?;
+        let mut writer = File::create(format!("/tmp/{}", node.name))?;
+        copy(&mut reader, &mut writer)?;
     }
 
     Ok(())
 }
-
-#[derive(Debug, Clone, Copy, PartialEq)]
-enum CompressionScheme {
-    None,
-    LZMA,
-    LZ4,
-    LZ4HC,
-    LZHAM,
-}
-impl CompressionScheme {
-    pub fn from_flag_num(n: u8) -> Option<CompressionScheme> {
-        Some(match n & 0x3f {
-            0 => CompressionScheme::None,
-            1 => CompressionScheme::LZMA,
-            2 => CompressionScheme::LZ4,
-            3 => CompressionScheme::LZ4HC,
-            4 => CompressionScheme::LZHAM,
-            _ => return None,
-        })
-    }
-    pub fn decompress(&self, block: Vec<u8>, decomp_size: usize) -> Result<Vec<u8>> {
-        match self {
-            CompressionScheme::None => Ok(block),
-            CompressionScheme::LZMA => {
-                let mut r = lzma::Reader::from(Cursor::new(block))?;
-                let mut buf = Vec::new();
-                r.read_to_end(&mut buf)?;
-                Ok(buf)
-            }
-            // CompressionScheme::LZ4HC | CompressionScheme::LZ4 => {
-            //     Ok(lz4_flex::block::decompress(&block, decomp_size).context("lz4 decomp")?)
-            // }
-            CompressionScheme::LZ4HC | CompressionScheme::LZ4 => {
-                File::create("/tmp/a")?.write_all(&block)?;
-                Ok(lz4::block::decompress(&block, Some(decomp_size as i32))?)
-                // Ok(lz4::block::decompress(&block, None)?)
-            }
-            CompressionScheme::LZHAM => todo!(),
-        }
-    }
-}