transaction interface

1 files changed, 46 insertions, 13 deletions

diff --git a/database/src/backends/memory.rs b/database/src/backends/memory.rs
index f1952a3..3c2fdea 100644
--- a/database/src/backends/memory.rs
+++ b/database/src/backends/memory.rs
@@ -4,10 +4,14 @@
     Copyright (C) 2025 metamuffin <metamuffin.org>
 */
 
-use crate::backends::KV;
+use crate::backends::{Db, ReadTransaction, ReadTxnFunction, WriteTransaction, WriteTxnFunction};
 use anyhow::Result;
-use std::{collections::BTreeMap, sync::RwLock};
+use std::{
+    collections::BTreeMap,
+    sync::{RwLock, RwLockReadGuard, RwLockWriteGuard},
+};
 
+type Inner = BTreeMap<Vec<u8>, Vec<u8>>;
 pub struct Memory(RwLock<BTreeMap<Vec<u8>, Vec<u8>>>);
 
 impl Memory {
@@ -15,25 +19,54 @@ impl Memory {
         Self(RwLock::new(BTreeMap::new()))
     }
 }
-impl KV for Memory {
-    fn set(&self, key: &[u8], value: &[u8]) -> Result<()> {
-        self.0.write().unwrap().insert(key.to_vec(), value.to_vec());
+impl Db for Memory {
+    fn write_transaction(&self, f: &mut WriteTxnFunction) -> Result<()> {
+        f(&mut self.0.write().unwrap())
+    }
+    fn read_transaction(&self, f: &mut ReadTxnFunction) -> Result<()> {
+        f(&self.0.read().unwrap())
+    }
+}
+impl WriteTransaction for RwLockWriteGuard<'_, Inner> {
+    fn set(&mut self, key: &[u8], value: &[u8]) -> Result<()> {
+        (**self).insert(key.to_vec(), value.to_vec());
+        Ok(())
+    }
+    fn del(&mut self, key: &[u8]) -> Result<()> {
+        (**self).remove(key);
         Ok(())
     }
+}
+impl ReadTransaction for RwLockWriteGuard<'_, Inner> {
     fn get(&self, key: &[u8]) -> Result<Option<Vec<u8>>> {
-        Ok(self.0.read().unwrap().get(key).cloned())
+        Ok((**self).get(key).cloned())
     }
-    fn del(&self, key: &[u8]) -> Result<()> {
-        self.0.write().unwrap().remove(key);
-        Ok(())
+    fn next(&self, key: &[u8]) -> Result<Option<Vec<u8>>> {
+        Ok((**self)
+            .range(key.to_vec()..)
+            .next()
+            .map(|(k, _)| k.to_owned()))
+    }
+    fn prev(&self, key: &[u8]) -> Result<Option<Vec<u8>>> {
+        Ok((**self)
+            .range(..key.to_vec())
+            .next_back()
+            .map(|(k, _)| k.to_owned()))
+    }
+}
+impl ReadTransaction for RwLockReadGuard<'_, Inner> {
+    fn get(&self, key: &[u8]) -> Result<Option<Vec<u8>>> {
+        Ok((**self).get(key).cloned())
     }
     fn next(&self, key: &[u8]) -> Result<Option<Vec<u8>>> {
-        let r = self.0.read().unwrap();
-        Ok(r.range(key.to_vec()..).next().map(|(k, _)| k.to_owned()))
+        Ok((**self)
+            .range(key.to_vec()..)
+            .next()
+            .map(|(k, _)| k.to_owned()))
     }
     fn prev(&self, key: &[u8]) -> Result<Option<Vec<u8>>> {
-        let r = self.0.read().unwrap();
-        Ok(r.range(..key.to_vec())
+        Ok((**self)
+            .range(..key.to_vec())
             .next_back()
             .map(|(k, _)| k.to_owned()))
     }