From c4c9d409c95c5e2c8bc93cb6057ae3171820da17 Mon Sep 17 00:00:00 2001
From: Nikita Sivukhin <sivukhin@turso.tech>
Date: Wed, 17 Sep 2025 16:35:36 +0400
Subject: [PATCH] remove io.block from op_checkpoint

---
 core/vdbe/execute.rs | 110 +++++++++++++++++++++++++++++++++++--------
 core/vdbe/mod.rs     |   8 ++--
 2 files changed, 96 insertions(+), 22 deletions(-)

diff --git a/core/vdbe/execute.rs b/core/vdbe/execute.rs
index e193cd05f..ccb7f4b3e 100644
--- a/core/vdbe/execute.rs
+++ b/core/vdbe/execute.rs
@@ -330,12 +330,35 @@ pub fn op_bit_not(
     Ok(InsnFunctionStepResult::Step)
 }
 
+#[derive(Debug)]
+pub enum OpCheckpointState {
+    StartCheckpoint,
+    FinishCheckpoint { result: Option<CheckpointResult> },
+    CompleteResult { result: Result<CheckpointResult> },
+}
+
 pub fn op_checkpoint(
     program: &Program,
     state: &mut ProgramState,
     insn: &Insn,
     pager: &Arc<Pager>,
     mv_store: Option<&Arc<MvStore>>,
+) -> Result<InsnFunctionStepResult> {
+    match op_checkpoint_inner(program, state, insn, pager, mv_store) {
+        Ok(result) => Ok(result),
+        Err(err) => {
+            state.op_checkpoint_state = OpCheckpointState::StartCheckpoint;
+            return Err(err);
+        }
+    }
+}
+
+pub fn op_checkpoint_inner(
+    program: &Program,
+    state: &mut ProgramState,
+    insn: &Insn,
+    pager: &Rc<Pager>,
+    mv_store: Option<&Arc<MvStore>>,
 ) -> Result<InsnFunctionStepResult> {
     load_insn!(
         Checkpoint {
@@ -352,26 +375,75 @@ pub fn op_checkpoint(
         // however.
         return Err(LimboError::TableLocked);
     }
-    let result = program.connection.checkpoint(*checkpoint_mode);
-    match result {
-        Ok(CheckpointResult {
-            num_attempted,
-            num_backfilled,
-            ..
-        }) => {
-            // https://sqlite.org/pragma.html#pragma_wal_checkpoint
-            // 1st col: 1 (checkpoint SQLITE_BUSY) or 0 (not busy).
-            state.registers[*dest] = Register::Value(Value::Integer(0));
-            // 2nd col: # modified pages written to wal file
-            state.registers[*dest + 1] = Register::Value(Value::Integer(num_attempted as i64));
-            // 3rd col: # pages moved to db after checkpoint
-            state.registers[*dest + 2] = Register::Value(Value::Integer(num_backfilled as i64));
-        }
-        Err(_err) => state.registers[*dest] = Register::Value(Value::Integer(1)),
-    }
+    loop {
+        match &mut state.op_checkpoint_state {
+            OpCheckpointState::StartCheckpoint => {
+                let step_result = program
+                    .connection
+                    .pager
+                    .borrow_mut()
+                    .wal_checkpoint_start(*checkpoint_mode);
+                match step_result {
+                    Ok(IOResult::Done(result)) => {
+                        state.op_checkpoint_state = OpCheckpointState::FinishCheckpoint {
+                            result: Some(result),
+                        };
+                        continue;
+                    }
+                    Ok(IOResult::IO(io)) => return Ok(InsnFunctionStepResult::IO(io)),
+                    Err(err) => {
+                        state.op_checkpoint_state =
+                            OpCheckpointState::CompleteResult { result: Err(err) };
+                        continue;
+                    }
+                }
+            }
+            OpCheckpointState::FinishCheckpoint { result } => {
+                let step_result = program
+                    .connection
+                    .pager
+                    .borrow_mut()
+                    .wal_checkpoint_finish(result.as_mut().unwrap());
+                match step_result {
+                    Ok(IOResult::Done(())) => {
+                        state.op_checkpoint_state = OpCheckpointState::CompleteResult {
+                            result: Ok(result.take().unwrap()),
+                        };
+                        continue;
+                    }
+                    Ok(IOResult::IO(io)) => return Ok(InsnFunctionStepResult::IO(io)),
+                    Err(err) => {
+                        state.op_checkpoint_state =
+                            OpCheckpointState::CompleteResult { result: Err(err) };
+                        continue;
+                    }
+                }
+            }
+            OpCheckpointState::CompleteResult { result } => {
+                match result {
+                    Ok(CheckpointResult {
+                        num_attempted,
+                        num_backfilled,
+                        ..
+                    }) => {
+                        // https://sqlite.org/pragma.html#pragma_wal_checkpoint
+                        // 1st col: 1 (checkpoint SQLITE_BUSY) or 0 (not busy).
+                        state.registers[*dest] = Register::Value(Value::Integer(0));
+                        // 2nd col: # modified pages written to wal file
+                        state.registers[*dest + 1] =
+                            Register::Value(Value::Integer(*num_attempted as i64));
+                        // 3rd col: # pages moved to db after checkpoint
+                        state.registers[*dest + 2] =
+                            Register::Value(Value::Integer(*num_backfilled as i64));
+                    }
+                    Err(_err) => state.registers[*dest] = Register::Value(Value::Integer(1)),
+                }
 
-    state.pc += 1;
-    Ok(InsnFunctionStepResult::Step)
+                state.pc += 1;
+                return Ok(InsnFunctionStepResult::Step);
+            }
+        }
+    }
 }
 
 pub fn op_null(
diff --git a/core/vdbe/mod.rs b/core/vdbe/mod.rs
index a39902bf0..66fc2a774 100644
--- a/core/vdbe/mod.rs
+++ b/core/vdbe/mod.rs
@@ -35,9 +35,9 @@ use crate::{
     types::{IOCompletions, IOResult, RawSlice, TextRef},
     vdbe::{
         execute::{
-            OpColumnState, OpDeleteState, OpDeleteSubState, OpIdxInsertState, OpInsertState,
-            OpInsertSubState, OpNewRowidState, OpNoConflictState, OpRowIdState, OpSeekState,
-            OpTransactionState,
+            OpCheckpointState, OpColumnState, OpDeleteState, OpDeleteSubState, OpIdxInsertState,
+            OpInsertState, OpInsertSubState, OpNewRowidState, OpNoConflictState, OpRowIdState,
+            OpSeekState, OpTransactionState,
         },
         metrics::StatementMetrics,
     },
@@ -292,6 +292,7 @@ pub struct ProgramState {
     op_column_state: OpColumnState,
     op_row_id_state: OpRowIdState,
     op_transaction_state: OpTransactionState,
+    op_checkpoint_state: OpCheckpointState,
     /// State machine for committing view deltas with I/O handling
     view_delta_state: ViewDeltaCommitState,
 }
@@ -336,6 +337,7 @@ impl ProgramState {
             op_column_state: OpColumnState::Start,
             op_row_id_state: OpRowIdState::Start,
             op_transaction_state: OpTransactionState::Start,
+            op_checkpoint_state: OpCheckpointState::StartCheckpoint,
             view_delta_state: ViewDeltaCommitState::NotStarted,
         }
     }