diff --git a/archapp/src/archeng.rs b/archapp/src/archeng.rs
index cddf4d7..9ec083d 100644
--- a/archapp/src/archeng.rs
+++ b/archapp/src/archeng.rs
@@ -1,4 +1,5 @@
 use err::Error;
+use netpod::log::*;
 use std::convert::TryInto;
 use std::path::PathBuf;
 use tokio::fs::OpenOptions;
@@ -8,7 +9,7 @@ use tokio::io::AsyncReadExt;
 // Wrap each I/O operation into a stopwatch to detect bad NFS performance!
 
 #[derive(Debug)]
-struct IndexFileBasics {
+pub struct IndexFileBasics {
     version: u8,
     name_hash_anchor_beg: u64,
     name_hash_anchor_len: u64,
@@ -23,26 +24,63 @@ struct IndexFileBasics {
     fa_header_len: u64,
 }
 
+impl IndexFileBasics {
+    pub fn file_offset_size(&self) -> u64 {
+        if self.version == 3 {
+            64
+        } else if self.version == 2 {
+            32
+        } else {
+            panic!()
+        }
+    }
+}
+
+pub fn name_hash(s: &str, ht_len: u32) -> u32 {
+    let mut h = 0;
+    for ch in s.as_bytes() {
+        h = (128 * h + *ch as u32) % ht_len;
+    }
+    h
+}
+
 pub async fn read_file_basics(path: PathBuf) -> Result<IndexFileBasics, Error> {
     let mut f1 = OpenOptions::new().read(true).open(path).await?;
-    let mut buf = vec![0; 0x34];
+    let mut buf = vec![0; 0x4000];
     f1.read_exact(&mut buf).await?;
     let version = String::from_utf8(buf[3..4].to_vec())?.parse()?;
+    fn readu64(buf: &[u8], pos: usize) -> u64 {
+        u64::from_be_bytes(buf.as_ref()[pos..pos + 8].try_into().unwrap()) as u64
+    }
+    fn readu32(buf: &[u8], pos: usize) -> u64 {
+        u32::from_be_bytes(buf.as_ref()[pos..pos + 4].try_into().unwrap()) as u64
+    }
+    let b = &buf;
+    //let s: String = b.iter().map(|x| format!(" {:02x}", *x)).collect();
+    //info!("\n\n{}", s);
+    let mut i1 = 0x2800;
+    while i1 < 0x2880 {
+        let s: String = b[i1..i1 + 8].iter().map(|x| format!(" {:02x}", *x)).collect();
+        info!("{}", s);
+        i1 += 8;
+    }
+    info!("{}", String::from_utf8_lossy(&b[0x2800..0x2880]));
     let ret = IndexFileBasics {
         version,
-        name_hash_anchor_beg: u32::from_be_bytes(buf[0x04..0x08].try_into().unwrap()) as u64,
-        name_hash_anchor_len: u32::from_be_bytes(buf[0x08..0x0c].try_into().unwrap()) as u64,
-        // TODO:
-        fa_used_list_beg: u32::from_le_bytes(buf[0x08..0x0c].try_into().unwrap()) as u64,
-        fa_used_list_end: u32::from_le_bytes(buf[0x08..0x0c].try_into().unwrap()) as u64,
-        fa_used_list_len: u32::from_le_bytes(buf[0x08..0x0c].try_into().unwrap()) as u64,
-        fa_free_list_beg: u32::from_le_bytes(buf[0x08..0x0c].try_into().unwrap()) as u64,
-        fa_free_list_end: u32::from_le_bytes(buf[0x08..0x0c].try_into().unwrap()) as u64,
-        fa_free_list_len: u32::from_le_bytes(buf[0x08..0x0c].try_into().unwrap()) as u64,
-        fa_header_prev: u32::from_le_bytes(buf[0x08..0x0c].try_into().unwrap()) as u64,
-        fa_header_next: u32::from_le_bytes(buf[0x08..0x0c].try_into().unwrap()) as u64,
-        fa_header_len: u32::from_le_bytes(buf[0x08..0x0c].try_into().unwrap()) as u64,
+        name_hash_anchor_beg: readu64(b, 0x04),
+        name_hash_anchor_len: readu32(b, 0x0c),
+        fa_used_list_len: readu64(b, 0x10),
+        fa_used_list_beg: readu64(b, 0x18),
+        fa_used_list_end: readu64(b, 0x20),
+        fa_free_list_len: readu64(b, 0x28),
+        fa_free_list_beg: readu64(b, 0x30),
+        fa_free_list_end: readu64(b, 0x38),
+        fa_header_len: readu64(b, 0x40),
+        fa_header_prev: readu64(b, 0x48),
+        fa_header_next: readu64(b, 0x50),
     };
+    let chn_hash = name_hash("X05DA-FE-WI1:TC1", ret.name_hash_anchor_len as u32);
+    info!("channel hash: {:08x}", chn_hash);
     Ok(ret)
 }
 
@@ -75,7 +113,8 @@ mod test {
         let fut = async {
             let res = read_file_basics(CHN_0_MASTER_INDEX.into()).await?;
             info!("got {:?}", res);
-            assert!(res.version == 2 || res.version == 3);
+            assert_eq!(res.version, 3);
+            assert_eq!(res.file_offset_size(), 64);
             Ok(())
         };
         Ok(taskrun::run(fut).unwrap())