881 lines
24 KiB
TypeScript
881 lines
24 KiB
TypeScript
import { prettyByte } from "./utils/prettyByte.ts";
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import { ExtensionCodec } from "./ExtensionCodec.ts";
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import { getInt64, getUint64, UINT32_MAX } from "./utils/int.ts";
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import { utf8Decode } from "./utils/utf8.ts";
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import { ensureUint8Array } from "./utils/typedArrays.ts";
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import { CachedKeyDecoder } from "./CachedKeyDecoder.ts";
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import { DecodeError } from "./DecodeError.ts";
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import type { ContextOf } from "./context.ts";
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import type { ExtensionCodecType } from "./ExtensionCodec.ts";
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import type { KeyDecoder } from "./CachedKeyDecoder.ts";
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export type DecoderOptions<ContextType = undefined> = Readonly<
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Partial<{
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extensionCodec: ExtensionCodecType<ContextType>;
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/**
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* Decodes Int64 and Uint64 as bigint if it's set to true.
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* Depends on ES2020's {@link DataView#getBigInt64} and
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* {@link DataView#getBigUint64}.
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*
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* Defaults to false.
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*/
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useBigInt64: boolean;
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/**
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* By default, string values will be decoded as UTF-8 strings. However, if this option is true,
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* string values will be returned as Uint8Arrays without additional decoding.
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*
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* This is useful if the strings may contain invalid UTF-8 sequences.
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*
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* Note that this option only applies to string values, not map keys. Additionally, when
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* enabled, raw string length is limited by the maxBinLength option.
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*/
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rawStrings: boolean;
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/**
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* Maximum string length.
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*
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* Defaults to 4_294_967_295 (UINT32_MAX).
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*/
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maxStrLength: number;
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/**
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* Maximum binary length.
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*
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* Defaults to 4_294_967_295 (UINT32_MAX).
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*/
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maxBinLength: number;
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/**
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* Maximum array length.
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*
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* Defaults to 4_294_967_295 (UINT32_MAX).
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*/
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maxArrayLength: number;
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/**
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* Maximum map length.
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*
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* Defaults to 4_294_967_295 (UINT32_MAX).
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*/
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maxMapLength: number;
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/**
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* Maximum extension length.
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*
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* Defaults to 4_294_967_295 (UINT32_MAX).
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*/
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maxExtLength: number;
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/**
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* An object key decoder. Defaults to the shared instance of {@link CachedKeyDecoder}.
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* `null` is a special value to disable the use of the key decoder at all.
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*/
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keyDecoder: KeyDecoder | null;
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/**
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* A function to convert decoded map key to a valid JS key type.
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*
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* Defaults to a function that throws an error if the key is not a string or a number.
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*/
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mapKeyConverter: (key: unknown) => MapKeyType;
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}>
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> &
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ContextOf<ContextType>;
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const STATE_ARRAY = "array";
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const STATE_MAP_KEY = "map_key";
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const STATE_MAP_VALUE = "map_value";
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type MapKeyType = string | number;
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const mapKeyConverter = (key: unknown): MapKeyType => {
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if (typeof key === "string" || typeof key === "number") {
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return key;
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}
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throw new DecodeError("The type of key must be string or number but " + typeof key);
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};
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type StackMapState = {
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type: typeof STATE_MAP_KEY | typeof STATE_MAP_VALUE;
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size: number;
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key: MapKeyType | null;
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readCount: number;
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map: Record<string, unknown>;
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};
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type StackArrayState = {
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type: typeof STATE_ARRAY;
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size: number;
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array: Array<unknown>;
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position: number;
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};
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class StackPool {
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private readonly stack: Array<StackState> = [];
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private stackHeadPosition = -1;
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public get length(): number {
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return this.stackHeadPosition + 1;
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}
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public top(): StackState | undefined {
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return this.stack[this.stackHeadPosition];
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}
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public pushArrayState(size: number) {
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const state = this.getUninitializedStateFromPool() as StackArrayState;
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state.type = STATE_ARRAY;
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state.position = 0;
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state.size = size;
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state.array = new Array(size);
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}
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public pushMapState(size: number) {
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const state = this.getUninitializedStateFromPool() as StackMapState;
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state.type = STATE_MAP_KEY;
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state.readCount = 0;
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state.size = size;
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state.map = {};
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}
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private getUninitializedStateFromPool() {
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this.stackHeadPosition++;
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if (this.stackHeadPosition === this.stack.length) {
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const partialState: Partial<StackState> = {
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type: undefined,
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size: 0,
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array: undefined,
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position: 0,
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readCount: 0,
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map: undefined,
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key: null,
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};
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this.stack.push(partialState as StackState);
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}
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return this.stack[this.stackHeadPosition];
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}
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public release(state: StackState): void {
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const topStackState = this.stack[this.stackHeadPosition];
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if (topStackState !== state) {
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throw new Error("Invalid stack state. Released state is not on top of the stack.");
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}
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if (state.type === STATE_ARRAY) {
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const partialState = state as Partial<StackArrayState>;
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partialState.size = 0;
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partialState.array = undefined;
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partialState.position = 0;
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partialState.type = undefined;
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}
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if (state.type === STATE_MAP_KEY || state.type === STATE_MAP_VALUE) {
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const partialState = state as Partial<StackMapState>;
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partialState.size = 0;
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partialState.map = undefined;
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partialState.readCount = 0;
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partialState.type = undefined;
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}
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this.stackHeadPosition--;
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}
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public reset(): void {
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this.stack.length = 0;
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this.stackHeadPosition = -1;
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}
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}
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type StackState = StackArrayState | StackMapState;
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const HEAD_BYTE_REQUIRED = -1;
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const EMPTY_VIEW = new DataView<ArrayBufferLike>(new ArrayBuffer(0));
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const EMPTY_BYTES = new Uint8Array<ArrayBufferLike>(EMPTY_VIEW.buffer);
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try {
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// IE11: The spec says it should throw RangeError,
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// IE11: but in IE11 it throws TypeError.
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EMPTY_VIEW.getInt8(0);
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} catch (e) {
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if (!(e instanceof RangeError)) {
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throw new Error(
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"This module is not supported in the current JavaScript engine because DataView does not throw RangeError on out-of-bounds access",
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);
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}
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}
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const MORE_DATA = new RangeError("Insufficient data");
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const sharedCachedKeyDecoder = new CachedKeyDecoder();
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export class Decoder<ContextType = undefined> {
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private readonly extensionCodec: ExtensionCodecType<ContextType>;
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private readonly context: ContextType;
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private readonly useBigInt64: boolean;
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private readonly rawStrings: boolean;
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private readonly maxStrLength: number;
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private readonly maxBinLength: number;
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private readonly maxArrayLength: number;
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private readonly maxMapLength: number;
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private readonly maxExtLength: number;
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private readonly keyDecoder: KeyDecoder | null;
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private readonly mapKeyConverter: (key: unknown) => MapKeyType;
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private totalPos = 0;
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private pos = 0;
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private view = EMPTY_VIEW;
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private bytes = EMPTY_BYTES;
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private headByte = HEAD_BYTE_REQUIRED;
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private readonly stack = new StackPool();
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private entered = false;
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public constructor(options?: DecoderOptions<ContextType>) {
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this.extensionCodec = options?.extensionCodec ?? (ExtensionCodec.defaultCodec as ExtensionCodecType<ContextType>);
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this.context = (options as { context: ContextType } | undefined)?.context as ContextType; // needs a type assertion because EncoderOptions has no context property when ContextType is undefined
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this.useBigInt64 = options?.useBigInt64 ?? false;
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this.rawStrings = options?.rawStrings ?? false;
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this.maxStrLength = options?.maxStrLength ?? UINT32_MAX;
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this.maxBinLength = options?.maxBinLength ?? UINT32_MAX;
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this.maxArrayLength = options?.maxArrayLength ?? UINT32_MAX;
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this.maxMapLength = options?.maxMapLength ?? UINT32_MAX;
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this.maxExtLength = options?.maxExtLength ?? UINT32_MAX;
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this.keyDecoder = options?.keyDecoder !== undefined ? options.keyDecoder : sharedCachedKeyDecoder;
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this.mapKeyConverter = options?.mapKeyConverter ?? mapKeyConverter;
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}
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private clone(): Decoder<ContextType> {
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// eslint-disable-next-line @typescript-eslint/no-unsafe-argument
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return new Decoder({
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extensionCodec: this.extensionCodec,
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context: this.context,
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useBigInt64: this.useBigInt64,
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rawStrings: this.rawStrings,
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maxStrLength: this.maxStrLength,
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maxBinLength: this.maxBinLength,
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maxArrayLength: this.maxArrayLength,
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maxMapLength: this.maxMapLength,
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maxExtLength: this.maxExtLength,
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keyDecoder: this.keyDecoder,
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} as any);
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}
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private reinitializeState() {
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this.totalPos = 0;
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this.headByte = HEAD_BYTE_REQUIRED;
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this.stack.reset();
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// view, bytes, and pos will be re-initialized in setBuffer()
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}
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private setBuffer(buffer: ArrayLike<number> | ArrayBufferView | ArrayBufferLike): void {
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const bytes = ensureUint8Array(buffer);
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this.bytes = bytes;
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this.view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength);
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this.pos = 0;
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}
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private appendBuffer(buffer: ArrayLike<number> | ArrayBufferView | ArrayBufferLike): void {
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if (this.headByte === HEAD_BYTE_REQUIRED && !this.hasRemaining(1)) {
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this.setBuffer(buffer);
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} else {
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const remainingData = this.bytes.subarray(this.pos);
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const newData = ensureUint8Array(buffer);
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// concat remainingData + newData
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const newBuffer = new Uint8Array(remainingData.length + newData.length);
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newBuffer.set(remainingData);
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newBuffer.set(newData, remainingData.length);
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this.setBuffer(newBuffer);
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}
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}
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private hasRemaining(size: number) {
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return this.view.byteLength - this.pos >= size;
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}
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private createExtraByteError(posToShow: number): Error {
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const { view, pos } = this;
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return new RangeError(`Extra ${view.byteLength - pos} of ${view.byteLength} byte(s) found at buffer[${posToShow}]`);
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}
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/**
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* @throws {@link DecodeError}
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* @throws {@link RangeError}
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*/
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public decode(buffer: ArrayLike<number> | ArrayBufferView | ArrayBufferLike): unknown {
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if (this.entered) {
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const instance = this.clone();
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return instance.decode(buffer);
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}
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try {
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this.entered = true;
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this.reinitializeState();
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this.setBuffer(buffer);
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const object = this.doDecodeSync();
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if (this.hasRemaining(1)) {
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throw this.createExtraByteError(this.pos);
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}
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return object;
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} finally {
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this.entered = false;
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}
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}
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public *decodeMulti(buffer: ArrayLike<number> | ArrayBufferView | ArrayBufferLike): Generator<unknown, void, unknown> {
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if (this.entered) {
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const instance = this.clone();
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yield* instance.decodeMulti(buffer);
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return;
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}
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try {
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this.entered = true;
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this.reinitializeState();
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this.setBuffer(buffer);
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while (this.hasRemaining(1)) {
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yield this.doDecodeSync();
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}
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} finally {
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this.entered = false;
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}
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}
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public async decodeAsync(stream: AsyncIterable<ArrayLike<number> | ArrayBufferView | ArrayBufferLike>): Promise<unknown> {
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if (this.entered) {
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const instance = this.clone();
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return instance.decodeAsync(stream);
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}
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try {
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this.entered = true;
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let decoded = false;
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let object: unknown;
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for await (const buffer of stream) {
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if (decoded) {
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this.entered = false;
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throw this.createExtraByteError(this.totalPos);
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}
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this.appendBuffer(buffer);
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try {
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object = this.doDecodeSync();
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decoded = true;
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} catch (e) {
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if (!(e instanceof RangeError)) {
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throw e; // rethrow
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}
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// fallthrough
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}
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this.totalPos += this.pos;
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}
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if (decoded) {
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if (this.hasRemaining(1)) {
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throw this.createExtraByteError(this.totalPos);
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}
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return object;
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}
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const { headByte, pos, totalPos } = this;
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throw new RangeError(
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`Insufficient data in parsing ${prettyByte(headByte)} at ${totalPos} (${pos} in the current buffer)`,
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);
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} finally {
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this.entered = false;
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}
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}
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public decodeArrayStream(
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stream: AsyncIterable<ArrayLike<number> | ArrayBufferView | ArrayBufferLike>,
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): AsyncGenerator<unknown, void, unknown> {
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return this.decodeMultiAsync(stream, true);
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}
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public decodeStream(stream: AsyncIterable<ArrayLike<number> | ArrayBufferView | ArrayBufferLike>): AsyncGenerator<unknown, void, unknown> {
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return this.decodeMultiAsync(stream, false);
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}
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private async *decodeMultiAsync(stream: AsyncIterable<ArrayLike<number> | ArrayBufferView | ArrayBufferLike>, isArray: boolean): AsyncGenerator<unknown, void, unknown> {
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if (this.entered) {
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const instance = this.clone();
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yield* instance.decodeMultiAsync(stream, isArray);
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return;
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}
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try {
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this.entered = true;
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let isArrayHeaderRequired = isArray;
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let arrayItemsLeft = -1;
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for await (const buffer of stream) {
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if (isArray && arrayItemsLeft === 0) {
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throw this.createExtraByteError(this.totalPos);
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}
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this.appendBuffer(buffer);
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if (isArrayHeaderRequired) {
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arrayItemsLeft = this.readArraySize();
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isArrayHeaderRequired = false;
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this.complete();
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}
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try {
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while (true) {
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yield this.doDecodeSync();
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if (--arrayItemsLeft === 0) {
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break;
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}
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}
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} catch (e) {
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if (!(e instanceof RangeError)) {
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throw e; // rethrow
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}
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// fallthrough
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}
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this.totalPos += this.pos;
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}
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} finally {
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this.entered = false;
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}
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}
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private doDecodeSync(): unknown {
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DECODE: while (true) {
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const headByte = this.readHeadByte();
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let object: unknown;
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if (headByte >= 0xe0) {
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// negative fixint (111x xxxx) 0xe0 - 0xff
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object = headByte - 0x100;
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} else if (headByte < 0xc0) {
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if (headByte < 0x80) {
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// positive fixint (0xxx xxxx) 0x00 - 0x7f
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object = headByte;
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} else if (headByte < 0x90) {
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// fixmap (1000 xxxx) 0x80 - 0x8f
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const size = headByte - 0x80;
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if (size !== 0) {
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this.pushMapState(size);
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this.complete();
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continue DECODE;
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} else {
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object = {};
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}
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} else if (headByte < 0xa0) {
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// fixarray (1001 xxxx) 0x90 - 0x9f
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const size = headByte - 0x90;
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if (size !== 0) {
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this.pushArrayState(size);
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this.complete();
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continue DECODE;
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} else {
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object = [];
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}
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} else {
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// fixstr (101x xxxx) 0xa0 - 0xbf
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const byteLength = headByte - 0xa0;
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object = this.decodeString(byteLength, 0);
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}
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} else if (headByte === 0xc0) {
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// nil
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object = null;
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} else if (headByte === 0xc2) {
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// false
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object = false;
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} else if (headByte === 0xc3) {
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// true
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object = true;
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} else if (headByte === 0xca) {
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// float 32
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object = this.readF32();
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} else if (headByte === 0xcb) {
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// float 64
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object = this.readF64();
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} else if (headByte === 0xcc) {
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// uint 8
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object = this.readU8();
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} else if (headByte === 0xcd) {
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// uint 16
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object = this.readU16();
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} else if (headByte === 0xce) {
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// uint 32
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object = this.readU32();
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} else if (headByte === 0xcf) {
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// uint 64
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if (this.useBigInt64) {
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object = this.readU64AsBigInt();
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} else {
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object = this.readU64();
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}
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} else if (headByte === 0xd0) {
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// int 8
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object = this.readI8();
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} else if (headByte === 0xd1) {
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// int 16
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object = this.readI16();
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} else if (headByte === 0xd2) {
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// int 32
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object = this.readI32();
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} else if (headByte === 0xd3) {
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// int 64
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if (this.useBigInt64) {
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object = this.readI64AsBigInt();
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} else {
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object = this.readI64();
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}
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} else if (headByte === 0xd9) {
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// str 8
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const byteLength = this.lookU8();
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object = this.decodeString(byteLength, 1);
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} else if (headByte === 0xda) {
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// str 16
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const byteLength = this.lookU16();
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object = this.decodeString(byteLength, 2);
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} else if (headByte === 0xdb) {
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// str 32
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const byteLength = this.lookU32();
|
|
object = this.decodeString(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 DecodeError(`Unrecognized type byte: ${prettyByte(headByte)}`);
|
|
}
|
|
|
|
this.complete();
|
|
|
|
const stack = this.stack;
|
|
while (stack.length > 0) {
|
|
// arrays and maps
|
|
const state = stack.top()!;
|
|
if (state.type === STATE_ARRAY) {
|
|
state.array[state.position] = object;
|
|
state.position++;
|
|
if (state.position === state.size) {
|
|
object = state.array;
|
|
stack.release(state);
|
|
} else {
|
|
continue DECODE;
|
|
}
|
|
} else if (state.type === STATE_MAP_KEY) {
|
|
if (object === "__proto__") {
|
|
throw new DecodeError("The key __proto__ is not allowed");
|
|
}
|
|
|
|
state.key = this.mapKeyConverter(object);
|
|
state.type = STATE_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) {
|
|
object = state.map;
|
|
stack.release(state);
|
|
} else {
|
|
state.key = null;
|
|
state.type = STATE_MAP_KEY;
|
|
continue DECODE;
|
|
}
|
|
}
|
|
}
|
|
|
|
return object;
|
|
}
|
|
}
|
|
|
|
private readHeadByte(): number {
|
|
if (this.headByte === HEAD_BYTE_REQUIRED) {
|
|
this.headByte = this.readU8();
|
|
// console.log("headByte", prettyByte(this.headByte));
|
|
}
|
|
|
|
return this.headByte;
|
|
}
|
|
|
|
private complete(): void {
|
|
this.headByte = HEAD_BYTE_REQUIRED;
|
|
}
|
|
|
|
private readArraySize(): number {
|
|
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 DecodeError(`Unrecognized array type byte: ${prettyByte(headByte)}`);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
private pushMapState(size: number) {
|
|
if (size > this.maxMapLength) {
|
|
throw new DecodeError(`Max length exceeded: map length (${size}) > maxMapLengthLength (${this.maxMapLength})`);
|
|
}
|
|
|
|
this.stack.pushMapState(size);
|
|
}
|
|
|
|
private pushArrayState(size: number) {
|
|
if (size > this.maxArrayLength) {
|
|
throw new DecodeError(`Max length exceeded: array length (${size}) > maxArrayLength (${this.maxArrayLength})`);
|
|
}
|
|
|
|
this.stack.pushArrayState(size);
|
|
}
|
|
|
|
private decodeString(byteLength: number, headerOffset: number): string | Uint8Array {
|
|
if (!this.rawStrings || this.stateIsMapKey()) {
|
|
return this.decodeUtf8String(byteLength, headerOffset);
|
|
}
|
|
return this.decodeBinary(byteLength, headerOffset);
|
|
}
|
|
|
|
/**
|
|
* @throws {@link RangeError}
|
|
*/
|
|
private decodeUtf8String(byteLength: number, headerOffset: number): string {
|
|
if (byteLength > this.maxStrLength) {
|
|
throw new DecodeError(
|
|
`Max length exceeded: UTF-8 byte length (${byteLength}) > maxStrLength (${this.maxStrLength})`,
|
|
);
|
|
}
|
|
|
|
if (this.bytes.byteLength < this.pos + headerOffset + byteLength) {
|
|
throw MORE_DATA;
|
|
}
|
|
|
|
const offset = this.pos + headerOffset;
|
|
let object: string;
|
|
if (this.stateIsMapKey() && this.keyDecoder?.canBeCached(byteLength)) {
|
|
object = this.keyDecoder.decode(this.bytes, offset, byteLength);
|
|
} else {
|
|
object = utf8Decode(this.bytes, offset, byteLength);
|
|
}
|
|
this.pos += headerOffset + byteLength;
|
|
return object;
|
|
}
|
|
|
|
private stateIsMapKey(): boolean {
|
|
if (this.stack.length > 0) {
|
|
const state = this.stack.top()!;
|
|
return state.type === STATE_MAP_KEY;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* @throws {@link RangeError}
|
|
*/
|
|
private decodeBinary(byteLength: number, headOffset: number): Uint8Array {
|
|
if (byteLength > this.maxBinLength) {
|
|
throw new DecodeError(`Max length exceeded: bin length (${byteLength}) > maxBinLength (${this.maxBinLength})`);
|
|
}
|
|
|
|
if (!this.hasRemaining(byteLength + headOffset)) {
|
|
throw MORE_DATA;
|
|
}
|
|
|
|
const offset = this.pos + headOffset;
|
|
const object = this.bytes.subarray(offset, offset + byteLength);
|
|
this.pos += headOffset + byteLength;
|
|
return object;
|
|
}
|
|
|
|
private decodeExtension(size: number, headOffset: number): unknown {
|
|
if (size > this.maxExtLength) {
|
|
throw new DecodeError(`Max length exceeded: ext length (${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);
|
|
}
|
|
|
|
private lookU8() {
|
|
return this.view.getUint8(this.pos);
|
|
}
|
|
|
|
private lookU16() {
|
|
return this.view.getUint16(this.pos);
|
|
}
|
|
|
|
private lookU32() {
|
|
return this.view.getUint32(this.pos);
|
|
}
|
|
|
|
private readU8(): number {
|
|
const value = this.view.getUint8(this.pos);
|
|
this.pos++;
|
|
return value;
|
|
}
|
|
|
|
private readI8(): number {
|
|
const value = this.view.getInt8(this.pos);
|
|
this.pos++;
|
|
return value;
|
|
}
|
|
|
|
private readU16(): number {
|
|
const value = this.view.getUint16(this.pos);
|
|
this.pos += 2;
|
|
return value;
|
|
}
|
|
|
|
private readI16(): number {
|
|
const value = this.view.getInt16(this.pos);
|
|
this.pos += 2;
|
|
return value;
|
|
}
|
|
|
|
private readU32(): number {
|
|
const value = this.view.getUint32(this.pos);
|
|
this.pos += 4;
|
|
return value;
|
|
}
|
|
|
|
private readI32(): number {
|
|
const value = this.view.getInt32(this.pos);
|
|
this.pos += 4;
|
|
return value;
|
|
}
|
|
|
|
private readU64(): number {
|
|
const value = getUint64(this.view, this.pos);
|
|
this.pos += 8;
|
|
return value;
|
|
}
|
|
|
|
private readI64(): number {
|
|
const value = getInt64(this.view, this.pos);
|
|
this.pos += 8;
|
|
return value;
|
|
}
|
|
|
|
private readU64AsBigInt(): bigint {
|
|
const value = this.view.getBigUint64(this.pos);
|
|
this.pos += 8;
|
|
return value;
|
|
}
|
|
|
|
private readI64AsBigInt(): bigint {
|
|
const value = this.view.getBigInt64(this.pos);
|
|
this.pos += 8;
|
|
return value;
|
|
}
|
|
|
|
private readF32() {
|
|
const value = this.view.getFloat32(this.pos);
|
|
this.pos += 4;
|
|
return value;
|
|
}
|
|
|
|
private readF64() {
|
|
const value = this.view.getFloat64(this.pos);
|
|
this.pos += 8;
|
|
return value;
|
|
}
|
|
}
|