Initial project import

node_modules/iobuffer/src/IOBuffer.ts

@@ -0,0 +1,697 @@
+import { decode, encode } from './text';
+
+const defaultByteLength = 1024 * 8;
+
+const hostBigEndian = (() => {
+  const array = new Uint8Array(4);
+  const view = new Uint32Array(array.buffer);
+  return !((view[0] = 1) & array[0]);
+})();
+
+type InputData = number | ArrayBufferLike | ArrayBufferView | IOBuffer | Buffer;
+
+const typedArrays = {
+  int8: globalThis.Int8Array,
+  uint8: globalThis.Uint8Array,
+  int16: globalThis.Int16Array,
+  uint16: globalThis.Uint16Array,
+  int32: globalThis.Int32Array,
+  uint32: globalThis.Uint32Array,
+  uint64: globalThis.BigUint64Array,
+  int64: globalThis.BigInt64Array,
+  float32: globalThis.Float32Array,
+  float64: globalThis.Float64Array,
+};
+
+type TypedArrays = typeof typedArrays;
+
+interface IOBufferOptions {
+  /**
+   * Ignore the first n bytes of the ArrayBuffer.
+   */
+  offset?: number;
+}
+
+export class IOBuffer {
+  /**
+   * Reference to the internal ArrayBuffer object.
+   */
+  public buffer: ArrayBufferLike;
+
+  /**
+   * Byte length of the internal ArrayBuffer.
+   */
+  public byteLength: number;
+
+  /**
+   * Byte offset of the internal ArrayBuffer.
+   */
+  public byteOffset: number;
+
+  /**
+   * Byte length of the internal ArrayBuffer.
+   */
+  public length: number;
+
+  /**
+   * The current offset of the buffer's pointer.
+   */
+  public offset: number;
+
+  private lastWrittenByte: number;
+  private littleEndian: boolean;
+
+  private _data: DataView;
+  private _mark: number;
+  private _marks: number[];
+
+  /**
+   * Create a new IOBuffer.
+   * @param data - The data to construct the IOBuffer with.
+   * If data is a number, it will be the new buffer's length<br>
+   * If data is `undefined`, the buffer will be initialized with a default length of 8Kb<br>
+   * If data is an ArrayBuffer, SharedArrayBuffer, an ArrayBufferView (Typed Array), an IOBuffer instance,
+   * or a Node.js Buffer, a view will be created over the underlying ArrayBuffer.
+   * @param options - An object for the options.
+   * @returns A new IOBuffer instance.
+   */
+  public constructor(
+    data: InputData = defaultByteLength,
+    options: IOBufferOptions = {},
+  ) {
+    let dataIsGiven = false;
+    if (typeof data === 'number') {
+      data = new ArrayBuffer(data);
+    } else {
+      dataIsGiven = true;
+      this.lastWrittenByte = data.byteLength;
+    }
+    const offset = options.offset ? options.offset >>> 0 : 0;
+    const byteLength = data.byteLength - offset;
+    let dvOffset = offset;
+    if (ArrayBuffer.isView(data) || data instanceof IOBuffer) {
+      if (data.byteLength !== data.buffer.byteLength) {
+        dvOffset = data.byteOffset + offset;
+      }
+      data = data.buffer;
+    }
+    if (dataIsGiven) {
+      this.lastWrittenByte = byteLength;
+    } else {
+      this.lastWrittenByte = 0;
+    }
+    this.buffer = data;
+    this.length = byteLength;
+    this.byteLength = byteLength;
+    this.byteOffset = dvOffset;
+    this.offset = 0;
+    this.littleEndian = true;
+    this._data = new DataView(this.buffer, dvOffset, byteLength);
+    this._mark = 0;
+    this._marks = [];
+  }
+
+  /**
+   * Checks if the memory allocated to the buffer is sufficient to store more
+   * bytes after the offset.
+   * @param byteLength - The needed memory in bytes.
+   * @returns `true` if there is sufficient space and `false` otherwise.
+   */
+  public available(byteLength = 1): boolean {
+    return this.offset + byteLength <= this.length;
+  }
+
+  /**
+   * Check if little-endian mode is used for reading and writing multi-byte
+   * values.
+   * @returns `true` if little-endian mode is used, `false` otherwise.
+   */
+  public isLittleEndian(): boolean {
+    return this.littleEndian;
+  }
+
+  /**
+   * Set little-endian mode for reading and writing multi-byte values.
+   * @returns This.
+   */
+  public setLittleEndian(): this {
+    this.littleEndian = true;
+    return this;
+  }
+
+  /**
+   * Check if big-endian mode is used for reading and writing multi-byte values.
+   * @returns `true` if big-endian mode is used, `false` otherwise.
+   */
+  public isBigEndian(): boolean {
+    return !this.littleEndian;
+  }
+
+  /**
+   * Switches to big-endian mode for reading and writing multi-byte values.
+   * @returns This.
+   */
+  public setBigEndian(): this {
+    this.littleEndian = false;
+    return this;
+  }
+
+  /**
+   * Move the pointer n bytes forward.
+   * @param n - Number of bytes to skip.
+   * @returns This.
+   */
+  public skip(n = 1): this {
+    this.offset += n;
+    return this;
+  }
+
+  /**
+   * Move the pointer n bytes backward.
+   * @param n - Number of bytes to move back.
+   * @returns This.
+   */
+  public back(n = 1): this {
+    this.offset -= n;
+    return this;
+  }
+
+  /**
+   * Move the pointer to the given offset.
+   * @param offset - The offset to move to.
+   * @returns This.
+   */
+  public seek(offset: number): this {
+    this.offset = offset;
+    return this;
+  }
+
+  /**
+   * Store the current pointer offset.
+   * @see {@link IOBuffer#reset}
+   * @returns This.
+   */
+  public mark(): this {
+    this._mark = this.offset;
+    return this;
+  }
+
+  /**
+   * Move the pointer back to the last pointer offset set by mark.
+   * @see {@link IOBuffer#mark}
+   * @returns This.
+   */
+  public reset(): this {
+    this.offset = this._mark;
+    return this;
+  }
+
+  /**
+   * Push the current pointer offset to the mark stack.
+   * @see {@link IOBuffer#popMark}
+   * @returns This.
+   */
+  public pushMark(): this {
+    this._marks.push(this.offset);
+    return this;
+  }
+
+  /**
+   * Pop the last pointer offset from the mark stack, and set the current
+   * pointer offset to the popped value.
+   * @see {@link IOBuffer#pushMark}
+   * @returns This.
+   */
+  public popMark(): this {
+    const offset = this._marks.pop();
+    if (offset === undefined) {
+      throw new Error('Mark stack empty');
+    }
+    this.seek(offset);
+    return this;
+  }
+
+  /**
+   * Move the pointer offset back to 0.
+   * @returns This.
+   */
+  public rewind(): this {
+    this.offset = 0;
+    return this;
+  }
+
+  /**
+   * Make sure the buffer has sufficient memory to write a given byteLength at
+   * the current pointer offset.
+   * If the buffer's memory is insufficient, this method will create a new
+   * buffer (a copy) with a length that is twice (byteLength + current offset).
+   * @param byteLength - The needed memory in bytes.
+   * @returns This.
+   */
+  public ensureAvailable(byteLength = 1): this {
+    if (!this.available(byteLength)) {
+      const lengthNeeded = this.offset + byteLength;
+      const newLength = lengthNeeded * 2;
+      const newArray = new Uint8Array(newLength);
+      newArray.set(new Uint8Array(this.buffer));
+      this.buffer = newArray.buffer;
+      this.length = newLength;
+      this.byteLength = newLength;
+      this._data = new DataView(this.buffer);
+    }
+    return this;
+  }
+
+  /**
+   * Read a byte and return false if the byte's value is 0, or true otherwise.
+   * Moves pointer forward by one byte.
+   * @returns The read boolean.
+   */
+  public readBoolean(): boolean {
+    return this.readUint8() !== 0;
+  }
+
+  /**
+   * Read a signed 8-bit integer and move pointer forward by 1 byte.
+   * @returns The read byte.
+   */
+  public readInt8(): number {
+    return this._data.getInt8(this.offset++);
+  }
+
+  /**
+   * Read an unsigned 8-bit integer and move pointer forward by 1 byte.
+   * @returns The read byte.
+   */
+  public readUint8(): number {
+    return this._data.getUint8(this.offset++);
+  }
+
+  /**
+   * Alias for {@link IOBuffer#readUint8}.
+   * @returns The read byte.
+   */
+  public readByte(): number {
+    return this.readUint8();
+  }
+
+  /**
+   * Read `n` bytes and move pointer forward by `n` bytes.
+   * @param n - Number of bytes to read.
+   * @returns The read bytes.
+   */
+  public readBytes(n = 1): Uint8Array {
+    return this.readArray(n, 'uint8');
+  }
+
+  /**
+   * Creates an array of corresponding to the type `type` and size `size`.
+   * For example type `uint8` will create a `Uint8Array`.
+   * @param size - size of the resulting array
+   * @param type - number type of elements to read
+   * @returns The read array.
+   */
+  public readArray<T extends keyof typeof typedArrays>(
+    size: number,
+    type: T,
+  ): InstanceType<TypedArrays[T]> {
+    const bytes = typedArrays[type].BYTES_PER_ELEMENT * size;
+    const offset = this.byteOffset + this.offset;
+    const slice = this.buffer.slice(offset, offset + bytes);
+    if (
+      this.littleEndian === hostBigEndian &&
+      type !== 'uint8' &&
+      type !== 'int8'
+    ) {
+      const slice = new Uint8Array(this.buffer.slice(offset, offset + bytes));
+      slice.reverse();
+      const returnArray = new typedArrays[type](slice.buffer);
+      this.offset += bytes;
+      returnArray.reverse();
+      return returnArray as InstanceType<TypedArrays[T]>;
+    }
+    const returnArray = new typedArrays[type](slice);
+    this.offset += bytes;
+    return returnArray as InstanceType<TypedArrays[T]>;
+  }
+
+  /**
+   * Read a 16-bit signed integer and move pointer forward by 2 bytes.
+   * @returns The read value.
+   */
+  public readInt16(): number {
+    const value = this._data.getInt16(this.offset, this.littleEndian);
+    this.offset += 2;
+    return value;
+  }
+
+  /**
+   * Read a 16-bit unsigned integer and move pointer forward by 2 bytes.
+   * @returns The read value.
+   */
+  public readUint16(): number {
+    const value = this._data.getUint16(this.offset, this.littleEndian);
+    this.offset += 2;
+    return value;
+  }
+
+  /**
+   * Read a 32-bit signed integer and move pointer forward by 4 bytes.
+   * @returns The read value.
+   */
+  public readInt32(): number {
+    const value = this._data.getInt32(this.offset, this.littleEndian);
+    this.offset += 4;
+    return value;
+  }
+
+  /**
+   * Read a 32-bit unsigned integer and move pointer forward by 4 bytes.
+   * @returns The read value.
+   */
+  public readUint32(): number {
+    const value = this._data.getUint32(this.offset, this.littleEndian);
+    this.offset += 4;
+    return value;
+  }
+
+  /**
+   * Read a 32-bit floating number and move pointer forward by 4 bytes.
+   * @returns The read value.
+   */
+  public readFloat32(): number {
+    const value = this._data.getFloat32(this.offset, this.littleEndian);
+    this.offset += 4;
+    return value;
+  }
+
+  /**
+   * Read a 64-bit floating number and move pointer forward by 8 bytes.
+   * @returns The read value.
+   */
+  public readFloat64(): number {
+    const value = this._data.getFloat64(this.offset, this.littleEndian);
+    this.offset += 8;
+    return value;
+  }
+
+  /**
+   * Read a 64-bit signed integer number and move pointer forward by 8 bytes.
+   * @returns The read value.
+   */
+  public readBigInt64(): bigint {
+    const value = this._data.getBigInt64(this.offset, this.littleEndian);
+    this.offset += 8;
+    return value;
+  }
+
+  /**
+   * Read a 64-bit unsigned integer number and move pointer forward by 8 bytes.
+   * @returns The read value.
+   */
+  public readBigUint64(): bigint {
+    const value = this._data.getBigUint64(this.offset, this.littleEndian);
+    this.offset += 8;
+    return value;
+  }
+
+  /**
+   * Read a 1-byte ASCII character and move pointer forward by 1 byte.
+   * @returns The read character.
+   */
+  public readChar(): string {
+    // eslint-disable-next-line unicorn/prefer-code-point
+    return String.fromCharCode(this.readInt8());
+  }
+
+  /**
+   * Read `n` 1-byte ASCII characters and move pointer forward by `n` bytes.
+   * @param n - Number of characters to read.
+   * @returns The read characters.
+   */
+  public readChars(n = 1): string {
+    let result = '';
+    for (let i = 0; i < n; i++) {
+      result += this.readChar();
+    }
+    return result;
+  }
+
+  /**
+   * Read the next `n` bytes, return a UTF-8 decoded string and move pointer
+   * forward by `n` bytes.
+   * @param n - Number of bytes to read.
+   * @returns The decoded string.
+   */
+  public readUtf8(n = 1): string {
+    return decode(this.readBytes(n));
+  }
+
+  /**
+   * Read the next `n` bytes, return a string decoded with `encoding` and move pointer
+   * forward by `n` bytes.
+   * If no encoding is passed, the function is equivalent to @see {@link IOBuffer#readUtf8}
+   * @param n - Number of bytes to read.
+   * @param encoding - The encoding to use. Default is 'utf8'.
+   * @returns The decoded string.
+   */
+  public decodeText(n = 1, encoding = 'utf8'): string {
+    return decode(this.readBytes(n), encoding);
+  }
+
+  /**
+   * Write 0xff if the passed value is truthy, 0x00 otherwise and move pointer
+   * forward by 1 byte.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeBoolean(value: unknown): this {
+    this.writeUint8(value ? 0xff : 0x00);
+    return this;
+  }
+
+  /**
+   * Write `value` as an 8-bit signed integer and move pointer forward by 1 byte.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeInt8(value: number): this {
+    this.ensureAvailable(1);
+    this._data.setInt8(this.offset++, value);
+    this._updateLastWrittenByte();
+    return this;
+  }
+
+  /**
+   * Write `value` as an 8-bit unsigned integer and move pointer forward by 1
+   * byte.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeUint8(value: number): this {
+    this.ensureAvailable(1);
+    this._data.setUint8(this.offset++, value);
+    this._updateLastWrittenByte();
+    return this;
+  }
+
+  /**
+   * An alias for {@link IOBuffer#writeUint8}.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeByte(value: number): this {
+    return this.writeUint8(value);
+  }
+
+  /**
+   * Write all elements of `bytes` as uint8 values and move pointer forward by
+   * `bytes.length` bytes.
+   * @param bytes - The array of bytes to write.
+   * @returns This.
+   */
+  public writeBytes(bytes: ArrayLike<number>): this {
+    this.ensureAvailable(bytes.length);
+    // eslint-disable-next-line @typescript-eslint/prefer-for-of
+    for (let i = 0; i < bytes.length; i++) {
+      this._data.setUint8(this.offset++, bytes[i]);
+    }
+    this._updateLastWrittenByte();
+    return this;
+  }
+
+  /**
+   * Write `value` as a 16-bit signed integer and move pointer forward by 2
+   * bytes.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeInt16(value: number): this {
+    this.ensureAvailable(2);
+    this._data.setInt16(this.offset, value, this.littleEndian);
+    this.offset += 2;
+    this._updateLastWrittenByte();
+    return this;
+  }
+
+  /**
+   * Write `value` as a 16-bit unsigned integer and move pointer forward by 2
+   * bytes.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeUint16(value: number): this {
+    this.ensureAvailable(2);
+    this._data.setUint16(this.offset, value, this.littleEndian);
+    this.offset += 2;
+    this._updateLastWrittenByte();
+    return this;
+  }
+
+  /**
+   * Write `value` as a 32-bit signed integer and move pointer forward by 4
+   * bytes.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeInt32(value: number): this {
+    this.ensureAvailable(4);
+    this._data.setInt32(this.offset, value, this.littleEndian);
+    this.offset += 4;
+    this._updateLastWrittenByte();
+    return this;
+  }
+
+  /**
+   * Write `value` as a 32-bit unsigned integer and move pointer forward by 4
+   * bytes.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeUint32(value: number): this {
+    this.ensureAvailable(4);
+    this._data.setUint32(this.offset, value, this.littleEndian);
+    this.offset += 4;
+    this._updateLastWrittenByte();
+    return this;
+  }
+
+  /**
+   * Write `value` as a 32-bit floating number and move pointer forward by 4
+   * bytes.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeFloat32(value: number): this {
+    this.ensureAvailable(4);
+    this._data.setFloat32(this.offset, value, this.littleEndian);
+    this.offset += 4;
+    this._updateLastWrittenByte();
+    return this;
+  }
+
+  /**
+   * Write `value` as a 64-bit floating number and move pointer forward by 8
+   * bytes.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeFloat64(value: number): this {
+    this.ensureAvailable(8);
+    this._data.setFloat64(this.offset, value, this.littleEndian);
+    this.offset += 8;
+    this._updateLastWrittenByte();
+    return this;
+  }
+
+  /**
+   * Write `value` as a 64-bit signed bigint and move pointer forward by 8
+   * bytes.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeBigInt64(value: bigint): this {
+    this.ensureAvailable(8);
+    this._data.setBigInt64(this.offset, value, this.littleEndian);
+    this.offset += 8;
+    this._updateLastWrittenByte();
+    return this;
+  }
+
+  /**
+   * Write `value` as a 64-bit unsigned bigint and move pointer forward by 8
+   * bytes.
+   * @param value - The value to write.
+   * @returns This.
+   */
+  public writeBigUint64(value: bigint): this {
+    this.ensureAvailable(8);
+    this._data.setBigUint64(this.offset, value, this.littleEndian);
+    this.offset += 8;
+    this._updateLastWrittenByte();
+    return this;
+  }
+
+  /**
+   * Write the charCode of `str`'s first character as an 8-bit unsigned integer
+   * and move pointer forward by 1 byte.
+   * @param str - The character to write.
+   * @returns This.
+   */
+  public writeChar(str: string): this {
+    // eslint-disable-next-line unicorn/prefer-code-point
+    return this.writeUint8(str.charCodeAt(0));
+  }
+
+  /**
+   * Write the charCodes of all `str`'s characters as 8-bit unsigned integers
+   * and move pointer forward by `str.length` bytes.
+   * @param str - The characters to write.
+   * @returns This.
+   */
+  public writeChars(str: string): this {
+    for (let i = 0; i < str.length; i++) {
+      // eslint-disable-next-line unicorn/prefer-code-point
+      this.writeUint8(str.charCodeAt(i));
+    }
+    return this;
+  }
+
+  /**
+   * UTF-8 encode and write `str` to the current pointer offset and move pointer
+   * forward according to the encoded length.
+   * @param str - The string to write.
+   * @returns This.
+   */
+  public writeUtf8(str: string): this {
+    return this.writeBytes(encode(str));
+  }
+
+  /**
+   * Export a Uint8Array view of the internal buffer.
+   * The view starts at the byte offset and its length
+   * is calculated to stop at the last written byte or the original length.
+   * @returns A new Uint8Array view.
+   */
+  public toArray(): Uint8Array {
+    return new Uint8Array(this.buffer, this.byteOffset, this.lastWrittenByte);
+  }
+
+  /**
+   *  Get the total number of bytes written so far, regardless of the current offset.
+   * @returns - Total number of bytes.
+   */
+  public getWrittenByteLength() {
+    return this.lastWrittenByte - this.byteOffset;
+  }
+
+  /**
+   * Update the last written byte offset
+   * @private
+   */
+  private _updateLastWrittenByte(): void {
+    if (this.offset > this.lastWrittenByte) {
+      this.lastWrittenByte = this.offset;
+    }
+  }
+}

node_modules/iobuffer/src/text.ts

@@ -0,0 +1,10 @@
+export function decode(bytes: Uint8Array, encoding = 'utf8'): string {
+  const decoder = new TextDecoder(encoding);
+  return decoder.decode(bytes);
+}
+
+const encoder = new TextEncoder();
+
+export function encode(str: string): Uint8Array {
+  return encoder.encode(str);
+}