vue-blocklink/src/base/eth/utils/abi_encoder/calldata/blocks/pointer.js

Vue support for the Blockchain Link browser extension

import * as ethUtil from 'ethereumjs-util';
import { constants } from '../../utils/constants';
import { CalldataBlock } from '../calldata_block';
export class PointerCalldataBlock extends CalldataBlock {
    constructor(name, signature, parentName, dependency, parent) {
        const headerSizeInBytes = PointerCalldataBlock._EMPTY_HEADER_SIZE;
        const bodySizeInBytes = PointerCalldataBlock._DEPENDENT_PAYLOAD_SIZE_IN_BYTES;
        super(name, signature, parentName, headerSizeInBytes, bodySizeInBytes);
        this._parent = parent;
        this._dependency = dependency;
        this._aliasFor = undefined;
    }
    toBuffer() {
        const destinationOffset = this._aliasFor !== undefined ? this._aliasFor.getOffsetInBytes() : this._dependency.getOffsetInBytes();
        const parentOffset = this._parent.getOffsetInBytes();
        const parentHeaderSize = this._parent.getHeaderSizeInBytes();
        const pointer = destinationOffset - (parentOffset + parentHeaderSize);
        const pointerHex = `0x${pointer.toString(constants.HEX_BASE)}`;
        const pointerBuf = ethUtil.toBuffer(pointerHex);
        const pointerBufPadded = ethUtil.setLengthLeft(pointerBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
        return pointerBufPadded;
    }
    getDependency() {
        return this._dependency;
    }
    setAlias(block) {
        this._aliasFor = block;
        this._setName(`${this.getName()} (alias for ${block.getName()})`);
    }
    getAlias() {
        return this._aliasFor;
    }
    getRawData() {
        const dependencyRawData = this._dependency.getRawData();
        const rawDataComponents = [];
        rawDataComponents.push(PointerCalldataBlock.RAW_DATA_START);
        rawDataComponents.push(dependencyRawData);
        rawDataComponents.push(PointerCalldataBlock.RAW_DATA_END);
        const rawData = Buffer.concat(rawDataComponents);
        return rawData;
    }
}
PointerCalldataBlock.RAW_DATA_START = Buffer.from('<');
PointerCalldataBlock.RAW_DATA_END = Buffer.from('>');
PointerCalldataBlock._DEPENDENT_PAYLOAD_SIZE_IN_BYTES = 32;
PointerCalldataBlock._EMPTY_HEADER_SIZE = 0;