From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Sun, 23 Aug 2020 00:06:57 +0000 (+0100)
Subject: fixes
X-Git-Tag: otter-0.2.0~1087
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=commitdiff_plain;h=e4b2ca520bfc5c3e25a96ac9c90241f0d0a7c409;p=otter.git

fixes
---

diff --git a/.gitignore b/.gitignore
index b1df170d..81a69249 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 templates/script.js
+save/lock
diff --git a/src/global.rs b/src/global.rs
index ac40901a..9bbcf90a 100644
--- a/src/global.rs
+++ b/src/global.rs
@@ -143,6 +143,7 @@ struct Global {
   players : RwLock<TokenTable<PlayerId>>,
   clients : RwLock<TokenTable<ClientId>>,
   config  : RwLock<Arc<ServerConfig>>,
+  save_area_lock : Mutex<Option<File>>,
   // xxx delete clients at some point!
 }
 
@@ -606,9 +607,20 @@ impl InstanceGuard<'_> {
     rmp_serde::decode::from_read(&mut f)?
   }
 
-  #[throws(OE)]
+  #[throws(StartupError)]
   pub fn load(name: InstanceName) -> InstanceRef {
-    // xxx should take a file lock on save area
+    {
+      let mut st = GLOBAL.save_area_lock.lock().unwrap();
+      let st = &mut *st;
+      if st.is_none() {
+        let lockfile = format!("{}/lock", config().save_directory);
+        *st = Some((||{
+          let file = File::create(&lockfile).context("open")?;
+          file.try_lock_exclusive().context("lock")?;
+          Ok::<_,AE>(file)
+        })().context(lockfile).context("lock global save area")?);
+      }
+    }
     // xxx check for deleted players, throw their tokens away
     let gs = {
       let mut gs : GameState = Self::load_something(&name, "g-")?;
diff --git a/src/imports.rs b/src/imports.rs
index c1959f71..5700f367 100644
--- a/src/imports.rs
+++ b/src/imports.rs
@@ -61,6 +61,8 @@ pub use index_vec::{define_index_type,index_vec,IndexVec,IndexSlice};
 
 pub use vecdeque_stableix::StableIndexVecDeque;
 
+pub use fs2::FileExt;
+
 pub use crate::global::*;
 pub use crate::gamestate::*;
 pub use crate::pieces::*;