core/io: Untie MemoryIO's lifetime of the IO layer

bindings/javascript/src/lib.rs

@@ -177,7 +177,7 @@ impl limbo_core::IO for IO {
         todo!();
     }
 
-    fn get_memory_io(&self) -> Option<Arc<limbo_core::MemoryIO>> {
-        todo!()
+    fn get_memory_io(&self) -> Arc<limbo_core::MemoryIO> {
+        Arc::new(limbo_core::MemoryIO::new())
     }
 }

bindings/wasm/lib.rs

@@ -306,8 +306,8 @@ impl limbo_core::IO for PlatformIO {
         (random_f64 * i64::MAX as f64) as i64
     }
 
-    fn get_memory_io(&self) -> Option<Arc<limbo_core::MemoryIO>> {
-        None // TODO: Make sure if memory isn't needed here
+    fn get_memory_io(&self) -> Arc<limbo_core::MemoryIO> {
+        Arc::new(limbo_core::MemoryIO::new())
     }
 }
 

core/io/generic.rs

@@ -6,14 +6,12 @@ use tracing::{debug, trace};
 use super::MemoryIO;
 
 pub struct GenericIO {
-    memory_io: Arc<MemoryIO>,
 }
 
 impl GenericIO {
     pub fn new() -> Result<Self> {
         debug!("Using IO backend 'generic'");
         Ok(Self {
-            memory_io: Arc::new(MemoryIO::new()),
         })
     }
 }
@@ -55,9 +53,9 @@ impl Clock for GenericIO {
         }
     }
 
-    fn get_memory_io(&self) -> Option<Arc<super::MemoryIO>> {
-        Some(self.memory_io.clone())
-    }    
+    fn get_memory_io(&self) -> Arc<MemoryIO> {
+        Arc::new(MemoryIO::new())
+    }   
 }
 
 pub struct GenericFile {

core/io/io_uring.rs

@@ -35,7 +35,6 @@ impl fmt::Display for UringIOError {
 
 pub struct UringIO {
     inner: Rc<RefCell<InnerUringIO>>,
-    memory_io: Arc<MemoryIO>,
 }
 
 unsafe impl Send for UringIO {}
@@ -79,7 +78,6 @@ impl UringIO {
         debug!("Using IO backend 'io-uring'");
         Ok(Self {
             inner: Rc::new(RefCell::new(inner)),
-            memory_io: Arc::new(MemoryIO::new()),
         })
     }
 }
@@ -210,8 +208,8 @@ impl Clock for UringIO {
         }
     }
     
-    fn get_memory_io(&self) -> Option<Arc<MemoryIO>> {
-        Some(self.memory_io.clone())
+    fn get_memory_io(&self) -> Arc<MemoryIO> {
+        Arc::new(MemoryIO::new())
     }
 }
 

core/io/memory.rs

@@ -59,8 +59,8 @@ impl IO for MemoryIO {
         i64::from_ne_bytes(buf)
     }
 
-    fn get_memory_io(&self) -> Option<Arc<MemoryIO>> {
-        None
+    fn get_memory_io(&self) -> Arc<MemoryIO> {
+        Arc::new(MemoryIO::new())
     }
 }
 

core/io/mod.rs

@@ -41,7 +41,7 @@ pub trait IO: Clock + Send + Sync {
 
     fn generate_random_number(&self) -> i64;
 
-    fn get_memory_io(&self) -> Option<Arc<MemoryIO>>;
+    fn get_memory_io(&self) -> Arc<MemoryIO>;
 }
 
 pub type Complete = dyn Fn(Arc<RefCell<Buffer>>);

core/io/unix.rs

@@ -167,7 +167,6 @@ pub struct UnixIO {
     poller: PollHandler,
     events: EventsHandler,
     callbacks: OwnedCallbacks,
-    memory_io: Arc<MemoryIO>,
 }
 
 unsafe impl Send for UnixIO {}
@@ -181,7 +180,6 @@ impl UnixIO {
             poller: PollHandler::new(),
             events: EventsHandler::new(),
             callbacks: OwnedCallbacks::new(),
-            memory_io: Arc::new(MemoryIO::new()),
         })
     }
 }
@@ -261,8 +259,8 @@ impl IO for UnixIO {
         i64::from_ne_bytes(buf)
     }
     
-    fn get_memory_io(&self) -> Option<Arc<MemoryIO>> {
-        Some(self.memory_io.clone())
+    fn get_memory_io(&self) -> Arc<MemoryIO> {
+        Arc::new(MemoryIO::new())
     }
 }
 

core/io/vfs.rs

@@ -70,8 +70,8 @@ impl VfsMod {
         }
     }
 
-    fn get_memory_io(&self) -> Option<Arc<MemoryIO>> {
-        None
+    fn get_memory_io(&self) -> Arc<MemoryIO> {
+        Arc::new(MemoryIO::new())
     }
 }
 

core/io/windows.rs

@@ -5,14 +5,12 @@ use std::sync::Arc;
 use tracing::{debug, trace};
 use super::MemoryIO;
 pub struct WindowsIO {
-    memory_io: Arc<MemoryIO>,
 }
 
 impl WindowsIO {
     pub fn new() -> Result<Self> {
         debug!("Using IO backend 'syscall'");
         Ok(Self {
-            memory_io: Arc::new(MemoryIO::new()),
         })
     }
 }
@@ -53,8 +51,8 @@ impl Clock for WindowsIO {
         }
     }
   
-    fn get_memory_io(&self) -> Option<Arc<MemoryIO>> {
-        Some(self.memory_io.clone())
+    fn get_memory_io(&self) -> Arc<MemoryIO> {
+        Arc::new(MemoryIO::new())
     }
 }
 

core/vdbe/execute.rs

@@ -38,7 +38,9 @@ use crate::{
     vector::{vector32, vector64, vector_distance_cos, vector_extract},
 };
 
-use crate::{info, BufferPool, MvCursor, OpenFlags, RefValue, Row, StepResult, TransactionState};
+use crate::{
+    info, BufferPool, MvCursor, OpenFlags, RefValue, Row, StepResult, TransactionState, IO,
+};
 
 use super::{
     insn::{Cookie, RegisterOrLiteral},
@@ -4523,11 +4525,7 @@ pub fn op_open_ephemeral(
     };
 
     let conn = program.connection.upgrade().unwrap();
-    // Only memory and vfs IOs returns None, so cloning is safe
-    let io = match conn.pager.io.get_memory_io() {
-        Some(io) => io,
-        None => conn.pager.io.clone(),
-    };
+    let io = conn.pager.io.get_memory_io();
 
     let file = io.open_file("", OpenFlags::Create, true)?;
     let page_io = Arc::new(FileMemoryStorage::new(file));

simulator/runner/io.rs

@@ -98,7 +98,7 @@ impl IO for SimulatorIO {
         self.rng.borrow_mut().next_u64() as i64
     }
 
-    fn get_memory_io(&self) -> Option<Arc<limbo_core::MemoryIO>> {
+    fn get_memory_io(&self) -> Arc<limbo_core::MemoryIO> {
         todo!()
     }
 }