diff options
Diffstat (limited to 'packages/utils/src/abi_encoder/calldata/calldata.ts')
| -rw-r--r-- | packages/utils/src/abi_encoder/calldata/calldata.ts | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/packages/utils/src/abi_encoder/calldata/calldata.ts b/packages/utils/src/abi_encoder/calldata/calldata.ts new file mode 100644 index 000000000..5ac4c1fe7 --- /dev/null +++ b/packages/utils/src/abi_encoder/calldata/calldata.ts @@ -0,0 +1,224 @@ + +import * as ethUtil from 'ethereumjs-util'; +import * as _ from 'lodash'; + +import * as Constants from '../constants'; +import { Queue } from '../utils/queue'; +import { EncodingRules } from '../utils/rules'; + +import { CalldataBlock } from './calldata_block'; +import * as CalldataBlocks from './calldata_blocks'; + +export class Calldata { + private readonly _rules: EncodingRules; + private _selector: string; + private _sizeInBytes: number; + private _root: CalldataBlock | undefined; + + private static _createQueue(block: CalldataBlock): Queue<CalldataBlock> { + const blockQueue = new Queue<CalldataBlock>(); + + // Base Case + if (!(block instanceof CalldataBlocks.MemberCalldataBlock)) { + blockQueue.push(block); + return blockQueue; + } + + // This is a Member Block + const memberBlock = block; + _.eachRight(memberBlock.getMembers(), (member: CalldataBlock) => { + if (member instanceof CalldataBlocks.MemberCalldataBlock) { + blockQueue.mergeFront(Calldata._createQueue(member)); + } else { + blockQueue.pushFront(member); + } + }); + + // Children + _.each(memberBlock.getMembers(), (member: CalldataBlock) => { + if (member instanceof CalldataBlocks.DependentCalldataBlock && member.getAlias() === undefined) { + const dependency = member.getDependency(); + if (dependency instanceof CalldataBlocks.MemberCalldataBlock) { + blockQueue.merge(Calldata._createQueue(dependency)); + } else { + blockQueue.push(dependency); + } + } + }); + + blockQueue.pushFront(memberBlock); + return blockQueue; + } + + public constructor(rules: EncodingRules) { + this._rules = rules; + this._selector = ''; + this._sizeInBytes = 0; + this._root = undefined; + } + + public optimize(): void { + if (this._root === undefined) { + throw new Error('expected root'); + } + + const blocksByHash: { [key: string]: CalldataBlock } = {}; + + // 1. Create a queue of subtrees by hash + // Note that they are ordered the same as + const subtreeQueue = Calldata._createQueue(this._root); + let block: CalldataBlock | undefined; + for (block = subtreeQueue.popBack(); block !== undefined; block = subtreeQueue.popBack()) { + if (block instanceof CalldataBlocks.DependentCalldataBlock) { + const dependencyBlockHashBuf = block.getDependency().computeHash(); + const dependencyBlockHash = ethUtil.bufferToHex(dependencyBlockHashBuf); + if (dependencyBlockHash in blocksByHash) { + const blockWithSameHash = blocksByHash[dependencyBlockHash]; + if (blockWithSameHash !== block.getDependency()) { + block.setAlias(blockWithSameHash); + } + } + continue; + } + + const blockHashBuf = block.computeHash(); + const blockHash = ethUtil.bufferToHex(blockHashBuf); + if (!(blockHash in blocksByHash)) { + blocksByHash[blockHash] = block; + } + } + } + + public toHexString(): string { + if (this._root === undefined) { + throw new Error('expected root'); + } + + if (this._rules.optimize) { + this.optimize(); + } + + const offsetQueue = Calldata._createQueue(this._root); + let block: CalldataBlock | undefined; + let offset = 0; + for (block = offsetQueue.pop(); block !== undefined; block = offsetQueue.pop()) { + block.setOffset(offset); + offset += block.getSizeInBytes(); + } + + const hexValue = this._rules.annotate ? this._generateAnnotatedHexString() : this._generateCondensedHexString(); + return hexValue; + } + + public getSelectorHex(): string { + return this._selector; + } + + public getSizeInBytes(): number { + return this._sizeInBytes; + } + + public setRoot(block: CalldataBlock): void { + this._root = block; + this._sizeInBytes += block.getSizeInBytes(); + } + + public setSelector(selector: string): void { + this._selector = selector.startsWith('0x') ? selector : `$0x${selector}`; + if (this._selector.length !== Constants.HEX_SELECTOR_LENGTH_IN_CHARS) { + throw new Error(`Invalid selector '${this._selector}'`); + } + this._sizeInBytes += Constants.HEX_SELECTOR_LENGTH_IN_BYTES; // @TODO: Used to be += 8. Bad? + } + + private _generateAnnotatedHexString(): string { + let hexValue = `${this._selector}`; + if (this._root === undefined) { + throw new Error('expected root'); + } + + const valueQueue = Calldata._createQueue(this._root); + + let block: CalldataBlock | undefined; + let offset = 0; + const functionBlock = valueQueue.peek(); + const functionName: string = functionBlock === undefined ? '' : functionBlock.getName(); + for (block = valueQueue.pop(); block !== undefined; block = valueQueue.pop()) { + // Process each block 1 word at a time + const size = block.getSizeInBytes(); + const name = block.getName(); + const parentName = block.getParentName(); + const prettyName = name.replace(`${parentName}.`, '').replace(`${functionName}.`, ''); + + // Current offset + let offsetStr = ''; + + // If this block is empty then it's a newline + const offsetPadding = 10; + const valuePadding = 74; + const namePadding = 80; + const evmWordStartIndex = 0; + const emptySize = 0; + let value = ''; + let nameStr = ''; + let line = ''; + if (size === emptySize) { + offsetStr = ' '.repeat(offsetPadding); + value = ' '.repeat(valuePadding); + nameStr = `### ${prettyName.padEnd(namePadding)}`; + line = `\n${offsetStr}${value}${nameStr}`; + } else { + offsetStr = `0x${offset.toString(Constants.HEX_BASE)}`.padEnd(offsetPadding); + value = ethUtil + .stripHexPrefix( + ethUtil.bufferToHex( + block.toBuffer().slice(evmWordStartIndex, Constants.EVM_WORD_WIDTH_IN_BYTES), + ), + ) + .padEnd(valuePadding); + if (block instanceof CalldataBlocks.MemberCalldataBlock) { + nameStr = `### ${prettyName.padEnd(namePadding)}`; + line = `\n${offsetStr}${value}${nameStr}`; + } else { + nameStr = ` ${prettyName.padEnd(namePadding)}`; + line = `${offsetStr}${value}${nameStr}`; + } + } + + for (let j = Constants.EVM_WORD_WIDTH_IN_BYTES; j < size; j += Constants.EVM_WORD_WIDTH_IN_BYTES) { + offsetStr = `0x${(offset + j).toString(Constants.HEX_BASE)}`.padEnd(offsetPadding); + value = ethUtil + .stripHexPrefix( + ethUtil.bufferToHex(block.toBuffer().slice(j, j + Constants.EVM_WORD_WIDTH_IN_BYTES)), + ) + .padEnd(valuePadding); + nameStr = ' '.repeat(namePadding); + line = `${line}\n${offsetStr}${value}${nameStr}`; + } + + // Append to hex value + hexValue = `${hexValue}\n${line}`; + offset += size; + } + + return hexValue; + } + + private _generateCondensedHexString(): string { + const selectorBuffer = ethUtil.toBuffer(this._selector); + if (this._root === undefined) { + throw new Error('expected root'); + } + + const valueQueue = Calldata._createQueue(this._root); + const valueBufs: Buffer[] = [selectorBuffer]; + let block: CalldataBlock | undefined; + for (block = valueQueue.pop(); block !== undefined; block = valueQueue.pop()) { + valueBufs.push(block.toBuffer()); + } + + const combinedBuffers = Buffer.concat(valueBufs); + const hexValue = ethUtil.bufferToHex(combinedBuffers); + return hexValue; + } +} |