@msgpack/msgpack
Version:
MessagePack for JavaScript/ECMA-262
574 lines • 19.8 kB
JavaScript
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.Decoder = exports.DataViewIndexOutOfBoundsError = void 0;
const prettyByte_1 = require("./utils/prettyByte");
const ExtensionCodec_1 = require("./ExtensionCodec");
const int_1 = require("./utils/int");
const utf8_1 = require("./utils/utf8");
const typedArrays_1 = require("./utils/typedArrays");
const CachedKeyDecoder_1 = require("./CachedKeyDecoder");
const isValidMapKeyType = (key) => {
const keyType = typeof key;
return keyType === "string" || keyType === "number";
};
const HEAD_BYTE_REQUIRED = -1;
const EMPTY_VIEW = new DataView(new ArrayBuffer(0));
const EMPTY_BYTES = new Uint8Array(EMPTY_VIEW.buffer);
// IE11: Hack to support IE11.
// IE11: Drop this hack and just use RangeError when IE11 is obsolete.
exports.DataViewIndexOutOfBoundsError = (() => {
try {
// IE11: The spec says it should throw RangeError,
// IE11: but in IE11 it throws TypeError.
EMPTY_VIEW.getInt8(0);
}
catch (e) {
return e.constructor;
}
throw new Error("never reached");
})();
const MORE_DATA = new exports.DataViewIndexOutOfBoundsError("Insufficient data");
const DEFAULT_MAX_LENGTH = 4294967295; // uint32_max
const sharedCachedKeyDecoder = new CachedKeyDecoder_1.CachedKeyDecoder();
class Decoder {
constructor(extensionCodec = ExtensionCodec_1.ExtensionCodec.defaultCodec, context = undefined, maxStrLength = DEFAULT_MAX_LENGTH, maxBinLength = DEFAULT_MAX_LENGTH, maxArrayLength = DEFAULT_MAX_LENGTH, maxMapLength = DEFAULT_MAX_LENGTH, maxExtLength = DEFAULT_MAX_LENGTH, keyDecoder = sharedCachedKeyDecoder) {
this.extensionCodec = extensionCodec;
this.context = context;
this.maxStrLength = maxStrLength;
this.maxBinLength = maxBinLength;
this.maxArrayLength = maxArrayLength;
this.maxMapLength = maxMapLength;
this.maxExtLength = maxExtLength;
this.keyDecoder = keyDecoder;
this.totalPos = 0;
this.pos = 0;
this.view = EMPTY_VIEW;
this.bytes = EMPTY_BYTES;
this.headByte = HEAD_BYTE_REQUIRED;
this.stack = [];
}
reinitializeState() {
this.totalPos = 0;
this.headByte = HEAD_BYTE_REQUIRED;
}
setBuffer(buffer) {
this.bytes = typedArrays_1.ensureUint8Array(buffer);
this.view = typedArrays_1.createDataView(this.bytes);
this.pos = 0;
}
appendBuffer(buffer) {
if (this.headByte === HEAD_BYTE_REQUIRED && !this.hasRemaining()) {
this.setBuffer(buffer);
}
else {
// retried because data is insufficient
const remainingData = this.bytes.subarray(this.pos);
const newData = typedArrays_1.ensureUint8Array(buffer);
const concated = new Uint8Array(remainingData.length + newData.length);
concated.set(remainingData);
concated.set(newData, remainingData.length);
this.setBuffer(concated);
}
}
hasRemaining(size = 1) {
return this.view.byteLength - this.pos >= size;
}
createExtraByteError(posToShow) {
const { view, pos } = this;
return new RangeError(`Extra ${view.byteLength - pos} of ${view.byteLength} byte(s) found at buffer[${posToShow}]`);
}
decode(buffer) {
this.reinitializeState();
this.setBuffer(buffer);
const object = this.doDecodeSync();
if (this.hasRemaining()) {
throw this.createExtraByteError(this.pos);
}
return object;
}
*decodeMulti(buffer) {
this.reinitializeState();
this.setBuffer(buffer);
while (this.hasRemaining()) {
yield this.doDecodeSync();
}
}
async decodeAsync(stream) {
let decoded = false;
let object;
for await (const buffer of stream) {
if (decoded) {
throw this.createExtraByteError(this.totalPos);
}
this.appendBuffer(buffer);
try {
object = this.doDecodeSync();
decoded = true;
}
catch (e) {
if (!(e instanceof exports.DataViewIndexOutOfBoundsError)) {
throw e; // rethrow
}
// fallthrough
}
this.totalPos += this.pos;
}
if (decoded) {
if (this.hasRemaining()) {
throw this.createExtraByteError(this.totalPos);
}
return object;
}
const { headByte, pos, totalPos } = this;
throw new RangeError(`Insufficient data in parsing ${prettyByte_1.prettyByte(headByte)} at ${totalPos} (${pos} in the current buffer)`);
}
decodeArrayStream(stream) {
return this.decodeMultiAsync(stream, true);
}
decodeStream(stream) {
return this.decodeMultiAsync(stream, false);
}
async *decodeMultiAsync(stream, isArray) {
let isArrayHeaderRequired = isArray;
let arrayItemsLeft = -1;
for await (const buffer of stream) {
if (isArray && arrayItemsLeft === 0) {
throw this.createExtraByteError(this.totalPos);
}
this.appendBuffer(buffer);
if (isArrayHeaderRequired) {
arrayItemsLeft = this.readArraySize();
isArrayHeaderRequired = false;
this.complete();
}
try {
while (true) {
yield this.doDecodeSync();
if (--arrayItemsLeft === 0) {
break;
}
}
}
catch (e) {
if (!(e instanceof exports.DataViewIndexOutOfBoundsError)) {
throw e; // rethrow
}
// fallthrough
}
this.totalPos += this.pos;
}
}
doDecodeSync() {
DECODE: while (true) {
const headByte = this.readHeadByte();
let object;
if (headByte >= 0xe0) {
// negative fixint (111x xxxx) 0xe0 - 0xff
object = headByte - 0x100;
}
else if (headByte < 0xc0) {
if (headByte < 0x80) {
// positive fixint (0xxx xxxx) 0x00 - 0x7f
object = headByte;
}
else if (headByte < 0x90) {
// fixmap (1000 xxxx) 0x80 - 0x8f
const size = headByte - 0x80;
if (size !== 0) {
this.pushMapState(size);
this.complete();
continue DECODE;
}
else {
object = {};
}
}
else if (headByte < 0xa0) {
// fixarray (1001 xxxx) 0x90 - 0x9f
const size = headByte - 0x90;
if (size !== 0) {
this.pushArrayState(size);
this.complete();
continue DECODE;
}
else {
object = [];
}
}
else {
// fixstr (101x xxxx) 0xa0 - 0xbf
const byteLength = headByte - 0xa0;
object = this.decodeUtf8String(byteLength, 0);
}
}
else if (headByte === 0xc0) {
// nil
object = null;
}
else if (headByte === 0xc2) {
// false
object = false;
}
else if (headByte === 0xc3) {
// true
object = true;
}
else if (headByte === 0xca) {
// float 32
object = this.readF32();
}
else if (headByte === 0xcb) {
// float 64
object = this.readF64();
}
else if (headByte === 0xcc) {
// uint 8
object = this.readU8();
}
else if (headByte === 0xcd) {
// uint 16
object = this.readU16();
}
else if (headByte === 0xce) {
// uint 32
object = this.readU32();
}
else if (headByte === 0xcf) {
// uint 64
object = this.readU64();
}
else if (headByte === 0xd0) {
// int 8
object = this.readI8();
}
else if (headByte === 0xd1) {
// int 16
object = this.readI16();
}
else if (headByte === 0xd2) {
// int 32
object = this.readI32();
}
else if (headByte === 0xd3) {
// int 64
object = this.readI64();
}
else if (headByte === 0xd9) {
// str 8
const byteLength = this.lookU8();
object = this.decodeUtf8String(byteLength, 1);
}
else if (headByte === 0xda) {
// str 16
const byteLength = this.lookU16();
object = this.decodeUtf8String(byteLength, 2);
}
else if (headByte === 0xdb) {
// str 32
const byteLength = this.lookU32();
object = this.decodeUtf8String(byteLength, 4);
}
else if (headByte === 0xdc) {
// array 16
const size = this.readU16();
if (size !== 0) {
this.pushArrayState(size);
this.complete();
continue DECODE;
}
else {
object = [];
}
}
else if (headByte === 0xdd) {
// array 32
const size = this.readU32();
if (size !== 0) {
this.pushArrayState(size);
this.complete();
continue DECODE;
}
else {
object = [];
}
}
else if (headByte === 0xde) {
// map 16
const size = this.readU16();
if (size !== 0) {
this.pushMapState(size);
this.complete();
continue DECODE;
}
else {
object = {};
}
}
else if (headByte === 0xdf) {
// map 32
const size = this.readU32();
if (size !== 0) {
this.pushMapState(size);
this.complete();
continue DECODE;
}
else {
object = {};
}
}
else if (headByte === 0xc4) {
// bin 8
const size = this.lookU8();
object = this.decodeBinary(size, 1);
}
else if (headByte === 0xc5) {
// bin 16
const size = this.lookU16();
object = this.decodeBinary(size, 2);
}
else if (headByte === 0xc6) {
// bin 32
const size = this.lookU32();
object = this.decodeBinary(size, 4);
}
else if (headByte === 0xd4) {
// fixext 1
object = this.decodeExtension(1, 0);
}
else if (headByte === 0xd5) {
// fixext 2
object = this.decodeExtension(2, 0);
}
else if (headByte === 0xd6) {
// fixext 4
object = this.decodeExtension(4, 0);
}
else if (headByte === 0xd7) {
// fixext 8
object = this.decodeExtension(8, 0);
}
else if (headByte === 0xd8) {
// fixext 16
object = this.decodeExtension(16, 0);
}
else if (headByte === 0xc7) {
// ext 8
const size = this.lookU8();
object = this.decodeExtension(size, 1);
}
else if (headByte === 0xc8) {
// ext 16
const size = this.lookU16();
object = this.decodeExtension(size, 2);
}
else if (headByte === 0xc9) {
// ext 32
const size = this.lookU32();
object = this.decodeExtension(size, 4);
}
else {
throw new Error(`Unrecognized type byte: ${prettyByte_1.prettyByte(headByte)}`);
}
this.complete();
const stack = this.stack;
while (stack.length > 0) {
// arrays and maps
const state = stack[stack.length - 1];
if (state.type === 0 /* ARRAY */) {
state.array[state.position] = object;
state.position++;
if (state.position === state.size) {
stack.pop();
object = state.array;
}
else {
continue DECODE;
}
}
else if (state.type === 1 /* MAP_KEY */) {
if (!isValidMapKeyType(object)) {
throw new Error("The type of key must be string or number but " + typeof object);
}
state.key = object;
state.type = 2 /* MAP_VALUE */;
continue DECODE;
}
else {
// it must be `state.type === State.MAP_VALUE` here
state.map[state.key] = object;
state.readCount++;
if (state.readCount === state.size) {
stack.pop();
object = state.map;
}
else {
state.key = null;
state.type = 1 /* MAP_KEY */;
continue DECODE;
}
}
}
return object;
}
}
readHeadByte() {
if (this.headByte === HEAD_BYTE_REQUIRED) {
this.headByte = this.readU8();
// console.log("headByte", prettyByte(this.headByte));
}
return this.headByte;
}
complete() {
this.headByte = HEAD_BYTE_REQUIRED;
}
readArraySize() {
const headByte = this.readHeadByte();
switch (headByte) {
case 0xdc:
return this.readU16();
case 0xdd:
return this.readU32();
default: {
if (headByte < 0xa0) {
return headByte - 0x90;
}
else {
throw new Error(`Unrecognized array type byte: ${prettyByte_1.prettyByte(headByte)}`);
}
}
}
}
pushMapState(size) {
if (size > this.maxMapLength) {
throw new Error(`Max length exceeded: map length (${size}) > maxMapLengthLength (${this.maxMapLength})`);
}
this.stack.push({
type: 1 /* MAP_KEY */,
size,
key: null,
readCount: 0,
map: {},
});
}
pushArrayState(size) {
if (size > this.maxArrayLength) {
throw new Error(`Max length exceeded: array length (${size}) > maxArrayLength (${this.maxArrayLength})`);
}
this.stack.push({
type: 0 /* ARRAY */,
size,
array: new Array(size),
position: 0,
});
}
decodeUtf8String(byteLength, headerOffset) {
var _a;
if (byteLength > this.maxStrLength) {
throw new Error(`Max length exceeded: UTF-8 byte length (${byteLength}) > maxStrLength (${this.maxStrLength})`);
}
if (this.bytes.byteLength < this.pos + headerOffset + byteLength) {
throw MORE_DATA;
}
const offset = this.pos + headerOffset;
let object;
if (this.stateIsMapKey() && ((_a = this.keyDecoder) === null || _a === void 0 ? void 0 : _a.canBeCached(byteLength))) {
object = this.keyDecoder.decode(this.bytes, offset, byteLength);
}
else if (byteLength > utf8_1.TEXT_DECODER_THRESHOLD) {
object = utf8_1.utf8DecodeTD(this.bytes, offset, byteLength);
}
else {
object = utf8_1.utf8DecodeJs(this.bytes, offset, byteLength);
}
this.pos += headerOffset + byteLength;
return object;
}
stateIsMapKey() {
if (this.stack.length > 0) {
const state = this.stack[this.stack.length - 1];
return state.type === 1 /* MAP_KEY */;
}
return false;
}
decodeBinary(byteLength, headOffset) {
if (byteLength > this.maxBinLength) {
throw new Error(`Max length exceeded: bin length (${byteLength}) > maxBinLength (${this.maxBinLength})`);
}
if (!this.hasRemaining(byteLength + headOffset)) {
throw MORE_DATA;
}
const offset = this.pos + headOffset;
const object = this.bytes.subarray(offset, offset + byteLength);
this.pos += headOffset + byteLength;
return object;
}
decodeExtension(size, headOffset) {
if (size > this.maxExtLength) {
throw new Error(`Max length exceeded: ext length (${size}) > maxExtLength (${this.maxExtLength})`);
}
const extType = this.view.getInt8(this.pos + headOffset);
const data = this.decodeBinary(size, headOffset + 1 /* extType */);
return this.extensionCodec.decode(data, extType, this.context);
}
lookU8() {
return this.view.getUint8(this.pos);
}
lookU16() {
return this.view.getUint16(this.pos);
}
lookU32() {
return this.view.getUint32(this.pos);
}
readU8() {
const value = this.view.getUint8(this.pos);
this.pos++;
return value;
}
readI8() {
const value = this.view.getInt8(this.pos);
this.pos++;
return value;
}
readU16() {
const value = this.view.getUint16(this.pos);
this.pos += 2;
return value;
}
readI16() {
const value = this.view.getInt16(this.pos);
this.pos += 2;
return value;
}
readU32() {
const value = this.view.getUint32(this.pos);
this.pos += 4;
return value;
}
readI32() {
const value = this.view.getInt32(this.pos);
this.pos += 4;
return value;
}
readU64() {
const value = int_1.getUint64(this.view, this.pos);
this.pos += 8;
return value;
}
readI64() {
const value = int_1.getInt64(this.view, this.pos);
this.pos += 8;
return value;
}
readF32() {
const value = this.view.getFloat32(this.pos);
this.pos += 4;
return value;
}
readF64() {
const value = this.view.getFloat64(this.pos);
this.pos += 8;
return value;
}
}
exports.Decoder = Decoder;
//# sourceMappingURL=Decoder.js.map