store 'events_are_aligned' in lmdb

chorus-lib/src/store/lmdb/mod.rs

@@ -10,6 +10,9 @@ use std::ops::Bound;
 
 mod retired;
 
+const FALSE: &[u8] = &[0];
+const TRUE: &[u8] = &[1];
+
 #[derive(Debug)]
 pub struct Lmdb {
     env: Env,
@@ -225,6 +228,30 @@ impl Lmdb {
         Ok(())
     }
 
+    pub fn get_if_events_are_aligned(&self) -> Result<bool, Error> {
+        let txn = self.read_txn()?;
+        match self.general.get(&txn, b"events_are_aligned")? {
+            None => Ok(false),
+            Some(bytes) => match bytes[0] {
+                0 => Ok(false),
+                _ => Ok(true),
+            },
+        }
+    }
+
+    pub fn set_if_events_are_aligned(
+        &self,
+        txn: &mut RwTxn<'_>,
+        events_are_aligned: bool,
+    ) -> Result<(), Error> {
+        let slice = match events_are_aligned {
+            false => FALSE,
+            true => TRUE,
+        };
+        self.general.put(txn, b"events_are_aligned", slice)?;
+        Ok(())
+    }
+
     // Index the event
     pub fn index(&self, txn: &mut RwTxn<'_>, event: &Event, offset: usize) -> Result<(), Error> {
         // Index by id

chorus-lib/src/store/mod.rs

@@ -24,9 +24,11 @@ impl Store {
     pub fn new(config: &Config) -> Result<Store, Error> {
         let lmdb = Lmdb::new(config)?;
 
+        let events_are_aligned = lmdb.get_if_events_are_aligned()?;
+
         let events = {
             let event_map_file = format!("{}/event.map", &config.data_directory);
-            EventStore::new(event_map_file, false)?
+            EventStore::new(event_map_file, events_are_aligned)?
         };
 
         let store = Store { lmdb, events };