vec: fix header reading of existing file

crates/brk_vec/examples/main.rs

@@ -1,13 +1,15 @@
 use std::{fs, path::Path};
 
-use brk_core::{DateIndex, Height, Version};
+use brk_core::{DateIndex, Height, Printable, Version};
 use brk_vec::{AnyVec, CollectableVec, Format, GenericStoredVec, StoredVec, VecIterator};
 
+type I = DateIndex;
 #[allow(clippy::upper_case_acronyms)]
-type VEC = StoredVec<DateIndex, u32>;
+type VEC = StoredVec<I, u32>;
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     let _ = fs::remove_dir_all("./vec");
+    let _ = fs::remove_file("./vec");
 
     let version = Version::TWO;
     let format = Format::Compressed;
@@ -15,12 +17,14 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     {
         let mut vec: VEC = StoredVec::forced_import(Path::new("."), "vec", version, format)?;
 
-        (0..21_u32).for_each(|v| {
+        (0..4_u32).for_each(|v| {
             vec.push(v);
         });
 
         let mut iter = vec.into_iter();
         dbg!(iter.get(0.into()));
+        dbg!(iter.get(1.into()));
+        dbg!(iter.get(2.into()));
         dbg!(iter.get(20.into()));
         dbg!(iter.get(21.into()));
 

crates/brk_vec/src/structs/header.rs

@@ -1,6 +1,6 @@
 use std::{
     fs::File,
-    io::{self, Read, Seek, SeekFrom},
+    io::{self, Seek, SeekFrom},
     os::unix::fs::FileExt,
     sync::Arc,
 };
@@ -103,7 +103,6 @@ impl HeaderInner {
             compressed: ZeroCopyBool::from(format),
         };
         header.write(file)?;
-        // dbg!(file.bytes().map(|b| b.unwrap()).collect::<Vec<_>>());
         file.seek(SeekFrom::End(0))?;
         Ok(header)
     }
@@ -117,12 +116,14 @@ impl HeaderInner {
         vec_version: Version,
         format: Format,
     ) -> Result<Self> {
-        if file.metadata()?.len() < HEADER_OFFSET as u64 {
+        let len = file.metadata()?.len();
+
+        if len < HEADER_OFFSET as u64 {
             return Err(Error::WrongLength);
         }
 
         let mut buf = [0; HEADER_OFFSET];
-        file.read_exact(&mut buf)?;
+        file.read_exact_at(&mut buf, 0)?;
 
         let header = HeaderInner::read_from_bytes(&buf)?;
 

crates/brk_vec/src/variants/raw.rs

@@ -28,8 +28,8 @@ pub struct RawVec<I, T> {
     parent: PathBuf,
     name: &'static str,
     pushed: Vec<T>,
-    phantom: PhantomData<I>,
     stored_len: Arc<AtomicUsize>,
+    phantom: PhantomData<I>,
 }
 
 impl<I, T> RawVec<I, T>
@@ -77,7 +77,9 @@ where
                     let header = Header::create_and_write(&mut file, version, Format::Raw)?;
                     (header, None)
                 }
-                _ => return Err(e.into()),
+                _ => {
+                    return Err(e.into());
+                }
             },
         };
 
@@ -92,8 +94,8 @@ where
             name: Box::leak(Box::new(name.to_string())),
             parent: parent.to_owned(),
             pushed: vec![],
-            phantom: PhantomData,
             stored_len: Arc::new(AtomicUsize::new(stored_len)),
+            phantom: PhantomData,
         })
     }
 
@@ -306,12 +308,11 @@ where
     type Item = (I, Cow<'a, T>);
 
     fn next(&mut self) -> Option<Self::Item> {
-        let mmap = &self.mmap;
         let index = self.index;
 
         let opt = self
             .vec
-            .get_or_read_(index, mmap)
+            .get_or_read_(index, &self.mmap)
             .unwrap()
             .map(|v| (I::from(index), v));