Contract Calls #47
Contract Calls #47
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| fn read_return_data(dest: *mut u8); | ||
| } | ||
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| pub fn call(contract: Bytes20, calldata: &[u8], value: Option<Bytes32>, gas: Option<u64>) -> Result<Vec<u8>, Vec<u8>> { |
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Would be useful to add documentation to this function, specifically regarding what the error result contains. In the case the unsafe call to read_return_data fails, what will be included in outs?
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Great idea, I've added some documentation :)
If read_return_data fails, then execution will halt before resuming client execution. So from the user's perspective, this isn't something they need to worry about unless they edit the crate to call read_return_data directly. I've still added a comment on that extern just in case though
| }; | ||
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| let contract = env.read_bytes20(contract)?; | ||
| let input = env.read_slice(calldata, calldata_len)?; |
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It feels sensible to check the max calldata size here before we do this read operation
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I've added a charge for the bytes, so this should be safe now.
However, we likely need to make the Rust => Go data copy lazy to avoid both DOS and uncontrollable gas costs.
| gas -= baseCost | ||
| gas = gas - gas/64 | ||
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Perhaps need validation that this is safe
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Nice catch, added a check
This PR uses the infrastructure from the following to add Wasm contract calls
This PR relies on
Additionally, this PR
call_contractandread_return_data, to use the newwasmer 3.2FunctionEnvMut::data_and_store_mutfunction for returning both an env and store.vm.ErrExecutionReverted.