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2025-06-30 09:38:03 +08:00
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.Pickle = void 0;
// sizeof(T).
const SIZE_INT32 = 4;
const SIZE_UINT32 = 4;
const SIZE_INT64 = 8;
const SIZE_UINT64 = 8;
const SIZE_FLOAT = 4;
const SIZE_DOUBLE = 8;
// The allocation granularity of the payload.
const PAYLOAD_UNIT = 64;
// Largest JS number.
const CAPACITY_READ_ONLY = 9007199254740992;
// Aligns 'i' by rounding it up to the next multiple of 'alignment'.
const alignInt = function (i, alignment) {
return i + ((alignment - (i % alignment)) % alignment);
};
// PickleIterator reads data from a Pickle. The Pickle object must remain valid
// while the PickleIterator object is in use.
class PickleIterator {
constructor(pickle) {
this.payload = pickle.getHeader();
this.payloadOffset = pickle.getHeaderSize();
this.readIndex = 0;
this.endIndex = pickle.getPayloadSize();
}
readBool() {
return this.readInt() !== 0;
}
readInt() {
return this.readBytes(SIZE_INT32, Buffer.prototype.readInt32LE);
}
readUInt32() {
return this.readBytes(SIZE_UINT32, Buffer.prototype.readUInt32LE);
}
readInt64() {
return this.readBytes(SIZE_INT64, Buffer.prototype.readBigInt64LE);
}
readUInt64() {
return this.readBytes(SIZE_UINT64, Buffer.prototype.readBigUInt64LE);
}
readFloat() {
return this.readBytes(SIZE_FLOAT, Buffer.prototype.readFloatLE);
}
readDouble() {
return this.readBytes(SIZE_DOUBLE, Buffer.prototype.readDoubleLE);
}
readString() {
return this.readBytes(this.readInt()).toString();
}
readBytes(length, method) {
const readPayloadOffset = this.getReadPayloadOffsetAndAdvance(length);
if (method != null) {
return method.call(this.payload, readPayloadOffset, length);
}
else {
return this.payload.slice(readPayloadOffset, readPayloadOffset + length);
}
}
getReadPayloadOffsetAndAdvance(length) {
if (length > this.endIndex - this.readIndex) {
this.readIndex = this.endIndex;
throw new Error('Failed to read data with length of ' + length);
}
const readPayloadOffset = this.payloadOffset + this.readIndex;
this.advance(length);
return readPayloadOffset;
}
advance(size) {
const alignedSize = alignInt(size, SIZE_UINT32);
if (this.endIndex - this.readIndex < alignedSize) {
this.readIndex = this.endIndex;
}
else {
this.readIndex += alignedSize;
}
}
}
// This class provides facilities for basic binary value packing and unpacking.
//
// The Pickle class supports appending primitive values (ints, strings, etc.)
// to a pickle instance. The Pickle instance grows its internal memory buffer
// dynamically to hold the sequence of primitive values. The internal memory
// buffer is exposed as the "data" of the Pickle. This "data" can be passed
// to a Pickle object to initialize it for reading.
//
// When reading from a Pickle object, it is important for the consumer to know
// what value types to read and in what order to read them as the Pickle does
// not keep track of the type of data written to it.
//
// The Pickle's data has a header which contains the size of the Pickle's
// payload. It can optionally support additional space in the header. That
// space is controlled by the header_size parameter passed to the Pickle
// constructor.
class Pickle {
constructor(buffer) {
if (buffer) {
this.header = buffer;
this.headerSize = buffer.length - this.getPayloadSize();
this.capacityAfterHeader = CAPACITY_READ_ONLY;
this.writeOffset = 0;
if (this.headerSize > buffer.length) {
this.headerSize = 0;
}
if (this.headerSize !== alignInt(this.headerSize, SIZE_UINT32)) {
this.headerSize = 0;
}
if (this.headerSize === 0) {
this.header = Buffer.alloc(0);
}
}
else {
this.header = Buffer.alloc(0);
this.headerSize = SIZE_UINT32;
this.capacityAfterHeader = 0;
this.writeOffset = 0;
this.resize(PAYLOAD_UNIT);
this.setPayloadSize(0);
}
}
static createEmpty() {
return new Pickle();
}
static createFromBuffer(buffer) {
return new Pickle(buffer);
}
getHeader() {
return this.header;
}
getHeaderSize() {
return this.headerSize;
}
createIterator() {
return new PickleIterator(this);
}
toBuffer() {
return this.header.slice(0, this.headerSize + this.getPayloadSize());
}
writeBool(value) {
return this.writeInt(value ? 1 : 0);
}
writeInt(value) {
return this.writeBytes(value, SIZE_INT32, Buffer.prototype.writeInt32LE);
}
writeUInt32(value) {
return this.writeBytes(value, SIZE_UINT32, Buffer.prototype.writeUInt32LE);
}
writeInt64(value) {
return this.writeBytes(BigInt(value), SIZE_INT64, Buffer.prototype.writeBigInt64LE);
}
writeUInt64(value) {
return this.writeBytes(BigInt(value), SIZE_UINT64, Buffer.prototype.writeBigUInt64LE);
}
writeFloat(value) {
return this.writeBytes(value, SIZE_FLOAT, Buffer.prototype.writeFloatLE);
}
writeDouble(value) {
return this.writeBytes(value, SIZE_DOUBLE, Buffer.prototype.writeDoubleLE);
}
writeString(value) {
const length = Buffer.byteLength(value, 'utf8');
if (!this.writeInt(length)) {
return false;
}
return this.writeBytes(value, length);
}
setPayloadSize(payloadSize) {
return this.header.writeUInt32LE(payloadSize, 0);
}
getPayloadSize() {
return this.header.readUInt32LE(0);
}
writeBytes(data, length, method) {
const dataLength = alignInt(length, SIZE_UINT32);
const newSize = this.writeOffset + dataLength;
if (newSize > this.capacityAfterHeader) {
this.resize(Math.max(this.capacityAfterHeader * 2, newSize));
}
if (method) {
method.call(this.header, data, this.headerSize + this.writeOffset);
}
else {
this.header.write(data, this.headerSize + this.writeOffset, length);
}
const endOffset = this.headerSize + this.writeOffset + length;
this.header.fill(0, endOffset, endOffset + dataLength - length);
this.setPayloadSize(newSize);
this.writeOffset = newSize;
return true;
}
resize(newCapacity) {
newCapacity = alignInt(newCapacity, PAYLOAD_UNIT);
this.header = Buffer.concat([this.header, Buffer.alloc(newCapacity)]);
this.capacityAfterHeader = newCapacity;
}
}
exports.Pickle = Pickle;
//# sourceMappingURL=pickle.js.map