vecs: part 3

crates/brk_vecs/src/file/layout.rs

@@ -5,7 +5,7 @@ use std::{collections::HashMap, fs, io::BufReader, path::Path};
 
 use bincode::decode_from_std_read;
 use bincode::{Decode, Encode, config};
-use brk_core::{Error, Result};
+use brk_core::Result;
 use parking_lot::RwLock;
 
 use crate::PAGE_SIZE;
@@ -155,10 +155,8 @@ impl Layout {
         Some(region)
     }
 
-    pub fn has_hole_and_is_big_enough(&self, start: u64, gap_needed: u64) -> bool {
-        self.start_to_hole
-            .get(&start)
-            .is_some_and(|gap| *gap >= gap_needed)
+    pub fn get_hole(&self, start: u64) -> Option<u64> {
+        self.start_to_hole.get(&start).copied()
     }
 
     pub fn remove_or_compress_hole_to_right(&mut self, start: u64, compress_by: u64) {

crates/brk_vecs/src/file/mod.rs

@@ -13,11 +13,12 @@ use parking_lot::{RwLock, RwLockReadGuard};
 mod layout;
 mod reader;
 mod region;
+mod regions;
 
 use layout::*;
+use reader::*;
 use region::*;
-
-use crate::file::reader::Reader;
+use regions::*;
 
 pub const PAGE_SIZE: u64 = 4096;
 
@@ -109,46 +110,53 @@ impl File {
         let reserved = region_lock.reserved();
         let left = region_lock.left();
         let data_len = data.len() as u64;
+        drop(region_lock);
 
         let new_left = at.map_or_else(|| left, |at| reserved - (at - start));
         let new_len = reserved - new_left;
 
+        // Write to reserved space if possible
         if new_left >= data_len {
-            drop(region_lock);
+            Self::write_to_mmap(&self.mmap.read(), at.unwrap_or(start), data);
+
             let mut region_lock = region.write();
             region_lock.set_len(new_len);
 
-            Self::write_to_mmap(&self.mmap.read(), at.unwrap_or(start), data);
+            // TODO: Flush layout
             return Ok(());
         }
 
-        let layout_lock = self.layout.read();
+        let mut layout_lock = self.layout.write();
 
         let hole_start = start + reserved;
-        if layout_lock.has_hole_and_is_big_enough(hole_start, reserved) {
-            drop(layout_lock);
-            let mut layout_lock = self.layout.write();
+        let hole = layout_lock.get_hole(hole_start);
+
+        // Expand region to the right if possible
+        if hole.is_some_and(|gap| gap >= reserved) {
+            Self::write_to_mmap(&self.mmap.read(), at.unwrap_or(start), data);
+
             layout_lock.remove_or_compress_hole_to_right(hole_start, reserved);
             drop(layout_lock);
 
-            drop(region_lock);
             let mut region_lock = region.write();
             region_lock.set_len(new_len);
             region_lock.set_reserved(reserved * 2);
 
-            Self::write_to_mmap(&self.mmap.read(), at.unwrap_or(start), data);
+            // TODO: Flush layout
             return Ok(());
         }
 
         let reserved = reserved * 2;
 
+        // Find hole big enough to move the region or the next depending on which is smaller to if possible
         if let Some(hole_start) = layout_lock.find_smallest_adequate_hole(reserved) {
-            drop(layout_lock);
-            let mut layout_lock = self.layout.write();
             layout_lock.remove_or_compress_hole_to_right(hole_start, reserved);
+            // TODO: Before every drop of layout.write flush to disk
             drop(layout_lock);
 
-            drop(region_lock);
+            // write
+            Self::write_to_mmap(&self.mmap.read(), at.unwrap_or(start), data);
+
             let mut region_lock = region.write();
             region_lock.set_start(hole_start);
             region_lock.set_len(new_len);
@@ -157,6 +165,9 @@ impl File {
             // TODO: create hole in prev position
 
             Self::write_to_mmap(&self.mmap.read(), at.unwrap_or(start), data);
+
+            // TODO: Flush layout
+            return Ok(());
         }
 
         // copy region to new position then lock and update region meta then remove

crates/brk_vecs/src/file/regions.rs

@@ -0,0 +1,14 @@
+use std::{
+    collections::HashMap,
+    fs,
+    sync::{Arc, RwLock},
+};
+
+use crate::file::region::Region;
+
+#[derive(Debug)]
+pub struct Regions {
+    file: fs::File,
+    id_to_index: HashMap<String, usize>,
+    index_to_region: Vec<Option<Arc<RwLock<Region>>>>,
+}