fix: in case of missing cell, return ITEM_MISSING error instead of ha…

…lting
nervosnetwork · Dec 11, 2018 · 707d661 · 707d661
1 parent 7727360
commit 707d661
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Showing 3 changed files with 19 additions and 14 deletions.
diff --git a/script/src/syscalls/load_cell.rs b/script/src/syscalls/load_cell.rs
@@ -1,4 +1,4 @@
-use crate::syscalls::{Source, LOAD_CELL_SYSCALL_NUMBER, SUCCESS};
+use crate::syscalls::{Source, ITEM_MISSING, LOAD_CELL_SYSCALL_NUMBER, SUCCESS};
 use ckb_core::transaction::CellOutput;
 use ckb_protocol::CellOutput as FbsCellOutput;
 use ckb_vm::{CoreMachine, Error as VMError, Memory, Register, Syscalls, A0, A1, A2, A3, A4, A7};
@@ -51,9 +51,12 @@ impl<'a, R: Register, M: Memory> Syscalls<R, M> for LoadCell<'a> {
         let index = machine.registers()[A3].to_usize();
         let source = Source::parse_from_u64(machine.registers()[A4].to_u64())?;
 
-        let cell = self
-            .fetch_cell(source, index)
-            .ok_or_else(|| VMError::OutOfBound)?;
+        let cell = self.fetch_cell(source, index);
+        if cell.is_none() {
+            machine.registers_mut()[A0] = R::from_u8(ITEM_MISSING);
+            return Ok(true);
+        }
+        let cell = cell.unwrap();
 
         // NOTE: this is a very expensive operation here since we need to copy
         // everything in a cell to a flatbuffer object, serialize the object

diff --git a/script/src/syscalls/load_cell_by_field.rs b/script/src/syscalls/load_cell_by_field.rs
@@ -50,9 +50,12 @@ impl<'a, R: Register, M: Memory> Syscalls<R, M> for LoadCellByField<'a> {
         let source = Source::parse_from_u64(machine.registers()[A4].to_u64())?;
         let field = CellField::parse_from_u64(machine.registers()[A5].to_u64())?;
 
-        let cell = self
-            .fetch_cell(source, index)
-            .ok_or_else(|| VMError::OutOfBound)?;
+        let cell = self.fetch_cell(source, index);
+        if cell.is_none() {
+            machine.registers_mut()[A0] = R::from_u8(ITEM_MISSING);
+            return Ok(true);
+        }
+        let cell = cell.unwrap();
 
         let return_code = match field {
             CellField::Capacity => {

diff --git a/script/src/syscalls/mod.rs b/script/src/syscalls/mod.rs
@@ -88,9 +88,7 @@ mod tests {
     use ckb_core::transaction::{CellInput, CellOutput, OutPoint};
     use ckb_protocol::{CellOutput as FbsCellOutput, OutPoint as FbsOutPoint, Script as FbsScript};
     use ckb_vm::machine::DefaultCoreMachine;
-    use ckb_vm::{
-        CoreMachine, Error as VMError, Memory, SparseMemory, Syscalls, A0, A1, A2, A3, A4, A5, A7,
-    };
+    use ckb_vm::{CoreMachine, Memory, SparseMemory, Syscalls, A0, A1, A2, A3, A4, A5, A7};
     use flatbuffers::FlatBufferBuilder;
     use hash::sha3_256;
     use numext_fixed_hash::H256;
@@ -163,7 +161,7 @@ mod tests {
         }
     }
 
-    fn _test_load_cell_out_of_bound(data: Vec<u8>) {
+    fn _test_load_cell_item_missing(data: Vec<u8>) {
         let mut machine = DefaultCoreMachine::<u64, SparseMemory>::default();
         let size_addr = 0;
         let addr = 100;
@@ -191,13 +189,14 @@ mod tests {
         let input_cells = vec![&input_cell];
         let mut load_cell = LoadCell::new(&outputs, &input_cells, &input_cell);
 
-        assert_eq!(load_cell.ecall(&mut machine), Err(VMError::OutOfBound)); // index out of bounds
+        assert!(load_cell.ecall(&mut machine).is_ok());
+        assert_eq!(machine.registers()[A0], ITEM_MISSING as u64);
     }
 
     proptest! {
         #[test]
-        fn test_load_cell_out_of_bound(data in any_with::<Vec<u8>>(size_range(1000).lift())) {
-            _test_load_cell_out_of_bound(data);
+        fn test_load_cell_item_missing(data in any_with::<Vec<u8>>(size_range(1000).lift())) {
+            _test_load_cell_item_missing(data);
         }
     }