acquiring session files

helix-view/src/editor.rs

@@ -5,6 +5,7 @@ use crate::{
     graphics::{CursorKind, Rect},
     info::Info,
     input::KeyEvent,
+    session::Session,
     theme::{self, Theme},
     tree::{self, Tree},
     Align, Document, DocumentId, View, ViewId,
@@ -829,6 +830,10 @@ impl Editor {
         }
     }
 
+    pub fn session(&self) -> anyhow::Result<Session> {
+        Session::new(std::env::current_dir()?)
+    }
+
     /// Current editing mode for the [`Editor`].
     pub fn mode(&self) -> Mode {
         self.mode

helix-view/src/session.rs

@@ -1,21 +1,40 @@
 use std::{
     fs::{File, OpenOptions},
-    path::{Path, PathBuf},
+    path::PathBuf,
 };
 
-use anyhow::Result;
+use anyhow::{Context, Result};
 use sha1_smol::Sha1;
 
 pub struct Session {
     path: PathBuf,
+    guard: Option<FileLock>,
 }
 
 impl Session {
+    // TODO: Allow custom session names to be passed.
     pub fn new(path: PathBuf) -> Result<Self> {
         let bytes = sys::path_as_bytes(path.as_path());
         let hash = Sha1::from(bytes).digest().to_string();
-        let path = helix_loader::cache_dir().join(hash);
-        Ok(Self { path })
+        let path = helix_loader::cache_dir().join("sessions").join(hash);
+        Ok(Self { path, guard: None })
+    }
+
+    // TODO: Return a FileLockGuard instead.
+    pub fn get(&mut self, filename: String) -> Result<File> {
+        if self.guard.is_none() {
+            let lock = FileLock::new(self.path.join(".helix.lock"))?;
+            lock.lock()?;
+
+            self.guard = Some(lock);
+        }
+
+        OpenOptions::new()
+            .read(true)
+            .write(true)
+            .create(true)
+            .open(self.path.join(filename))
+            .context("failed to open file")
     }
 }
 
@@ -24,7 +43,12 @@ pub struct FileLock {
 }
 
 impl FileLock {
-    pub fn new(path: &Path) -> Result<Self> {
+    pub fn new(path: PathBuf) -> Result<Self> {
+        if let Some(parent) = path.parent() {
+            if !parent.exists() {
+                std::fs::DirBuilder::new().recursive(true).create(parent)?;
+            }
+        }
         let file = OpenOptions::new().write(true).create(true).open(path)?;
         Ok(Self { file })
     }