pallet_revive/
tracing.rs

1// This file is part of Substrate.
2
3// Copyright (C) Parity Technologies (UK) Ltd.
4// SPDX-License-Identifier: Apache-2.0
5
6// Licensed under the Apache License, Version 2.0 (the "License");
7// you may not use this file except in compliance with the License.
8// You may obtain a copy of the License at
9//
10// 	http://www.apache.org/licenses/LICENSE-2.0
11//
12// Unless required by applicable law or agreed to in writing, software
13// distributed under the License is distributed on an "AS IS" BASIS,
14// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15// See the License for the specific language governing permissions and
16// limitations under the License.
17
18use crate::{Code, DispatchError, Key, Weight, evm::Bytes, primitives::ExecReturnValue};
19use alloc::vec::Vec;
20use environmental::environmental;
21use sp_core::{H160, H256, U256};
22
23environmental!(tracer: dyn Tracing + 'static);
24
25/// Synthetic syscall name used for tracing PVM interpreter fuel consumption between real syscalls.
26pub const PVM_FUEL_NAME: &str = "pvm_fuel";
27
28/// Trace the execution of the given closure.
29///
30/// # Warning
31///
32/// Only meant to be called from off-chain code as its additional resource usage is
33/// not accounted for in the weights or memory envelope.
34pub fn trace<R, F: FnOnce() -> R>(tracer: &mut (dyn Tracing + 'static), f: F) -> R {
35	tracer::using_once(tracer, f)
36}
37
38/// Run the closure when tracing is enabled.
39///
40/// This is safe to be called from on-chain code as tracing will never be activated
41/// there. Hence the closure is not executed in this case.
42pub(crate) fn if_tracing<R, F: FnOnce(&mut (dyn Tracing + 'static)) -> R>(f: F) -> Option<R> {
43	tracer::with(f)
44}
45
46/// Interface to provide frame trace information for the current execution frame.
47pub trait FrameTraceInfo {
48	/// Get the amount of gas remaining in the current frame.
49	fn gas_left(&self) -> u64;
50
51	/// Returns how much weight was spent
52	fn weight_consumed(&self) -> Weight;
53
54	/// Get the output from the last frame.
55	fn last_frame_output(&self) -> Bytes;
56}
57
58/// Interface to provide EVM-specific trace information for the current execution frame.
59pub trait EVMFrameTraceInfo: FrameTraceInfo {
60	/// Get a snapshot of the memory at this point in execution.
61	///
62	/// # Parameters
63	/// - `limit`: Maximum number of memory words to capture.
64	fn memory_snapshot(&self, limit: usize) -> Vec<Bytes>;
65
66	/// Get a snapshot of the stack at this point in execution.
67	fn stack_snapshot(&self) -> Vec<Bytes>;
68}
69
70/// Defines methods to trace contract interactions.
71///
72/// # Contract
73///
74/// Every [`Tracing::enter_opcode`] and [`Tracing::enter_ecall`] must be followed by exactly one
75/// [`Tracing::exit_step`], on every path including reverts and traps. Tracers pair the two to
76/// attribute a step's cost, so an unmatched call charges that step to an enclosing one.
77pub trait Tracing {
78	/// Register an address that should be traced.
79	fn watch_address(&mut self, _addr: &H160) {}
80
81	/// Called before a contract call is executed.
82	///
83	/// - `code_address`: When code is loaded from a different address than `to` (DELEGATECALL or
84	///   EIP-7702 delegation), this is that source address.
85	/// - `is_delegate_call`: true for DELEGATECALL frames (not EIP-7702 delegation).
86	/// - `gas_limit`: gas forwarded to the child call
87	fn enter_child_span(
88		&mut self,
89		_from: H160,
90		_to: H160,
91		_code_address: Option<H160>,
92		_is_delegate_call: bool,
93		_is_read_only: bool,
94		_value: U256,
95		_input: &[u8],
96		_gas_limit: u64,
97	) {
98	}
99
100	/// Called when a contract calls terminates (selfdestructs)
101	fn terminate(
102		&mut self,
103		_contract_address: H160,
104		_beneficiary_address: H160,
105		_gas_left: u64,
106		_value: U256,
107	) {
108	}
109
110	/// Record the next code and salt to be instantiated.
111	fn instantiate_code(&mut self, _code: &Code, _salt: Option<&[u8; 32]>) {}
112
113	/// Called when a balance is read
114	fn balance_read(&mut self, _addr: &H160, _value: U256) {}
115
116	/// Called when storage read is called
117	fn storage_read(&mut self, _key: &Key, _value: Option<&[u8]>) {}
118
119	/// Called when storage write is called
120	fn storage_write(
121		&mut self,
122		_key: &Key,
123		_old_value: Option<Vec<u8>>,
124		_new_value: Option<&[u8]>,
125	) {
126	}
127
128	/// Record a log event
129	fn log_event(&mut self, _event: H160, _topics: &[H256], _data: &[u8], _log_index: u32) {}
130
131	/// Called after a contract call is executed
132	fn exit_child_span(
133		&mut self,
134		_output: &ExecReturnValue,
135		_gas_used: u64,
136		_weight_consumed: Weight,
137	) {
138	}
139
140	/// Called when a contract call terminates with an error
141	fn exit_child_span_with_error(
142		&mut self,
143		_error: DispatchError,
144		_gas_used: u64,
145		_weight_consumed: Weight,
146	) {
147	}
148
149	/// Check if the tracer is an execution tracer.
150	fn is_execution_tracer(&self) -> bool {
151		false
152	}
153
154	/// Called before an EVM opcode is executed.
155	///
156	/// # Parameters
157	/// - `pc`: The current program counter.
158	/// - `opcode`: The opcode being executed.
159	/// - `trace_info`: Information about the current execution frame.
160	fn enter_opcode(&mut self, _pc: u64, _opcode: u8, _trace_info: &dyn EVMFrameTraceInfo) {}
161
162	/// Called before a PVM syscall is executed.
163	///
164	/// # Parameters
165	/// - `ecall`: The name of the syscall being executed.
166	/// - `args`: The syscall arguments (register values).
167	/// - `trace_info`: Information about the current execution frame.
168	fn enter_ecall(
169		&mut self,
170		_ecall: &'static str,
171		_args: &[u64],
172		_trace_info: &dyn FrameTraceInfo,
173	) {
174	}
175
176	/// Called after an EVM opcode or PVM syscall is executed to record the gas cost.
177	///
178	/// # Parameters
179	/// - `trace_info`: Information about the current execution frame.
180	/// - `returned`: The syscall return value (PVM only, `None` for EVM opcodes).
181	fn exit_step(&mut self, _trace_info: &dyn FrameTraceInfo, _returned: Option<u64>) {}
182
183	/// Called once the transaction completes to report the gas consumed by the meter.
184	///
185	/// # Parameters
186	/// - `base_call_weight`: Extrinsic base weight that is added on top of `weight_consumed` when
187	///   charging.
188	/// - `weight_consumed`: Weight used by the transaction logic, excluding the extrinsic base
189	///   weight.
190	fn dispatch_result(&mut self, _base_call_weight: Weight, _weight_consumed: Weight) {}
191}
pallet_revive/tracing.rs

pallet_revive/
tracing.rs
