wip

Author: marvin-j97

README.md

@@ -76,14 +76,13 @@ Future breaking changes will result in a major version bump.
 ...
 [trailer]
 [magic, 4 bytes]
-; TODO: put version here, change magic(s)    
+[version, 1 byte, 0x1]
 [checksum type, 1 byte, always 0x0]
 [toc checksum, 16 bytes]
-[toc_pointer, 8 bytes]
+[toc pos, 8 bytes]
+[toc len, 8 bytes]
 ```
 
-<!-- TODO: store ToC len (in bytes) in trailer -->
-
 All integers are little-endian encoded.
 
 ## License

src/error.rs

@@ -10,6 +10,9 @@ pub enum Error {
     /// IO error
     Io(std::io::Error),
 
+    /// Invalid header
+    InvalidHeader,
+
     /// Unsupported file format version
     InvalidVersion,
 

src/toc/writer.rs

@@ -6,7 +6,7 @@ use crate::{checksum::Checksum, toc::entry::TocEntry};
 use byteorder::WriteBytesExt;
 use std::io::Write;
 
-pub const TOC_MAGIC: &[u8] = b"TOC1";
+pub const TOC_MAGIC: &[u8] = b"TOC!";
 
 struct ChecksummedWriter<W: std::io::Write> {
     inner: W,

src/trailer/reader.rs

@@ -8,7 +8,7 @@ use byteorder::ReadBytesExt;
 use std::io::{Read, Seek, SeekFrom};
 
 #[allow(clippy::cast_possible_wrap)]
-const TRAILER_SIZE: i64 = TRAILER_MAGIC.len() as i64 + 1 + 16 + 8;
+const TRAILER_SIZE: i64 = TRAILER_MAGIC.len() as i64 + 1 + 1 + 16 + 8 + 8;
 
 #[derive(Debug, Eq, PartialEq)]
 pub struct ParsedTrailer {
@@ -31,6 +31,14 @@ impl TrailerReader {
             reader.read_exact(&mut buf)?;
 
             if buf != TRAILER_MAGIC {
+                log::error!("Invalid trailer header");
+                return Err(crate::Error::InvalidHeader);
+            }
+        }
+
+        {
+            let version = reader.read_u8()?;
+            if version != 0x1 {
                 log::error!("Invalid version");
                 return Err(crate::Error::InvalidVersion);
             }
@@ -46,6 +54,7 @@ impl TrailerReader {
 
         let toc_checksum = Checksum::from_raw(reader.read_u128::<LE>()?);
         let toc_pos = reader.read_u64::<LE>()?;
+        // let _toc_len = reader.read_u64::<LE>()?;
 
         Ok(ParsedTrailer {
             toc_checksum,

src/trailer/writer.rs

@@ -5,7 +5,7 @@
 use crate::checksum::Checksum;
 use byteorder::WriteBytesExt;
 
-pub const TRAILER_MAGIC: &[u8] = b"TRA1";
+pub const TRAILER_MAGIC: &[u8] = b"SFA!";
 
 pub struct TrailerWriter;
 
@@ -14,15 +14,18 @@ impl TrailerWriter {
         mut writer: W,
         toc_checksum: Checksum,
         toc_pos: u64,
+        toc_len: u64,
     ) -> crate::Result<()> {
         use byteorder::LE;
 
         log::trace!("Writing trailer");
 
         writer.write_all(TRAILER_MAGIC)?;
+        writer.write_u8(0x1)?; // Version
         writer.write_u8(0x0)?; // Checksum type, xxh3 = 0x0
         writer.write_u128::<LE>(toc_checksum.into_u128())?;
         writer.write_u64::<LE>(toc_pos)?;
+        writer.write_u64::<LE>(toc_len)?;
 
         Ok(())
     }

src/writer.rs

@@ -102,8 +102,11 @@ impl Writer {
         let toc_pos = self.writer.stream_position()?;
         let toc_checksum = TocWriter::write_into(&mut self.writer, &self.toc)?;
 
+        let after_toc_pos = self.writer.stream_position()?;
+        let toc_len = after_toc_pos - toc_pos;
+
         // Write trailer
-        TrailerWriter::write_into(&mut self.writer, toc_checksum, toc_pos)?;
+        TrailerWriter::write_into(&mut self.writer, toc_checksum, toc_pos, toc_len)?;
 
         // Flush & sync
         log::trace!("Syncing file");

test_fixture/cherry_pie_broken

@@ -5,6 +5,7 @@ use std::io::{Read, Write};
 pub fn cherry_pie() -> Result<(), sfa::Error> {
     let dir = tempfile::tempdir()?;
     let path = dir.path().join("cherry_pie");
+    // let path = std::path::Path::new("test_fixture/cherry_pie_broken");
 
     let mut writer = Writer::new_at_path(&path)?;
     writer.start("Verse 1")?;