91 lines
3.4 KiB
JavaScript
91 lines
3.4 KiB
JavaScript
"use strict";
|
|
//See: https://github.com/ethereum/wiki/wiki/RLP
|
|
Object.defineProperty(exports, "__esModule", { value: true });
|
|
exports.decodeRlp = void 0;
|
|
const data_js_1 = require("./data.js");
|
|
const errors_js_1 = require("./errors.js");
|
|
const data_js_2 = require("./data.js");
|
|
function hexlifyByte(value) {
|
|
let result = value.toString(16);
|
|
while (result.length < 2) {
|
|
result = "0" + result;
|
|
}
|
|
return "0x" + result;
|
|
}
|
|
function unarrayifyInteger(data, offset, length) {
|
|
let result = 0;
|
|
for (let i = 0; i < length; i++) {
|
|
result = (result * 256) + data[offset + i];
|
|
}
|
|
return result;
|
|
}
|
|
function _decodeChildren(data, offset, childOffset, length) {
|
|
const result = [];
|
|
while (childOffset < offset + 1 + length) {
|
|
const decoded = _decode(data, childOffset);
|
|
result.push(decoded.result);
|
|
childOffset += decoded.consumed;
|
|
if (childOffset > offset + 1 + length) {
|
|
(0, errors_js_1.throwError)("child data too short", "BUFFER_OVERRUN", {
|
|
buffer: data, length, offset
|
|
});
|
|
}
|
|
}
|
|
return { consumed: (1 + length), result: result };
|
|
}
|
|
// returns { consumed: number, result: Object }
|
|
function _decode(data, offset) {
|
|
if (data.length === 0) {
|
|
(0, errors_js_1.throwError)("data too short", "BUFFER_OVERRUN", {
|
|
buffer: data, length: 0, offset: 1
|
|
});
|
|
}
|
|
const checkOffset = (offset) => {
|
|
if (offset > data.length) {
|
|
(0, errors_js_1.throwError)("data short segment too short", "BUFFER_OVERRUN", {
|
|
buffer: data, length: data.length, offset
|
|
});
|
|
}
|
|
};
|
|
// Array with extra length prefix
|
|
if (data[offset] >= 0xf8) {
|
|
const lengthLength = data[offset] - 0xf7;
|
|
checkOffset(offset + 1 + lengthLength);
|
|
const length = unarrayifyInteger(data, offset + 1, lengthLength);
|
|
checkOffset(offset + 1 + lengthLength + length);
|
|
return _decodeChildren(data, offset, offset + 1 + lengthLength, lengthLength + length);
|
|
}
|
|
else if (data[offset] >= 0xc0) {
|
|
const length = data[offset] - 0xc0;
|
|
checkOffset(offset + 1 + length);
|
|
return _decodeChildren(data, offset, offset + 1, length);
|
|
}
|
|
else if (data[offset] >= 0xb8) {
|
|
const lengthLength = data[offset] - 0xb7;
|
|
checkOffset(offset + 1 + lengthLength);
|
|
const length = unarrayifyInteger(data, offset + 1, lengthLength);
|
|
checkOffset(offset + 1 + lengthLength + length);
|
|
const result = (0, data_js_1.hexlify)(data.slice(offset + 1 + lengthLength, offset + 1 + lengthLength + length));
|
|
return { consumed: (1 + lengthLength + length), result: result };
|
|
}
|
|
else if (data[offset] >= 0x80) {
|
|
const length = data[offset] - 0x80;
|
|
checkOffset(offset + 1 + length);
|
|
const result = (0, data_js_1.hexlify)(data.slice(offset + 1, offset + 1 + length));
|
|
return { consumed: (1 + length), result: result };
|
|
}
|
|
return { consumed: 1, result: hexlifyByte(data[offset]) };
|
|
}
|
|
/**
|
|
* Decodes %%data%% into the structured data it represents.
|
|
*/
|
|
function decodeRlp(_data) {
|
|
const data = (0, data_js_2.getBytes)(_data, "data");
|
|
const decoded = _decode(data, 0);
|
|
if (decoded.consumed !== data.length) {
|
|
(0, errors_js_1.throwArgumentError)("unexpected junk after rlp payload", "data", _data);
|
|
}
|
|
return decoded.result;
|
|
}
|
|
exports.decodeRlp = decodeRlp;
|
|
//# sourceMappingURL=rlp-decode.js.map
|