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diff --git a/node_modules/browserify-zlib/src/index.js b/node_modules/browserify-zlib/src/index.js
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+'use strict';
+
+const Buffer = require('buffer').Buffer;
+const Transform = require('stream').Transform;
+const binding = require('./binding');
+const util = require('util');
+const assert = require('assert').ok;
+const kMaxLength = require('buffer').kMaxLength;
+const kRangeErrorMessage = 'Cannot create final Buffer. It would be larger ' +
+ 'than 0x' + kMaxLength.toString(16) + ' bytes';
+
+// zlib doesn't provide these, so kludge them in following the same
+// const naming scheme zlib uses.
+binding.Z_MIN_WINDOWBITS = 8;
+binding.Z_MAX_WINDOWBITS = 15;
+binding.Z_DEFAULT_WINDOWBITS = 15;
+
+// fewer than 64 bytes per chunk is stupid.
+// technically it could work with as few as 8, but even 64 bytes
+// is absurdly low. Usually a MB or more is best.
+binding.Z_MIN_CHUNK = 64;
+binding.Z_MAX_CHUNK = Infinity;
+binding.Z_DEFAULT_CHUNK = (16 * 1024);
+
+binding.Z_MIN_MEMLEVEL = 1;
+binding.Z_MAX_MEMLEVEL = 9;
+binding.Z_DEFAULT_MEMLEVEL = 8;
+
+binding.Z_MIN_LEVEL = -1;
+binding.Z_MAX_LEVEL = 9;
+binding.Z_DEFAULT_LEVEL = binding.Z_DEFAULT_COMPRESSION;
+
+// expose all the zlib constants
+const bkeys = Object.keys(binding);
+for (var bk = 0; bk < bkeys.length; bk++) {
+ var bkey = bkeys[bk];
+ if (bkey.match(/^Z/)) {
+ Object.defineProperty(exports, bkey, {
+ enumerable: true, value: binding[bkey], writable: false
+ });
+ }
+}
+
+// translation table for return codes.
+const codes = {
+ Z_OK: binding.Z_OK,
+ Z_STREAM_END: binding.Z_STREAM_END,
+ Z_NEED_DICT: binding.Z_NEED_DICT,
+ Z_ERRNO: binding.Z_ERRNO,
+ Z_STREAM_ERROR: binding.Z_STREAM_ERROR,
+ Z_DATA_ERROR: binding.Z_DATA_ERROR,
+ Z_MEM_ERROR: binding.Z_MEM_ERROR,
+ Z_BUF_ERROR: binding.Z_BUF_ERROR,
+ Z_VERSION_ERROR: binding.Z_VERSION_ERROR
+};
+
+const ckeys = Object.keys(codes);
+for (var ck = 0; ck < ckeys.length; ck++) {
+ var ckey = ckeys[ck];
+ codes[codes[ckey]] = ckey;
+}
+
+Object.defineProperty(exports, 'codes', {
+ enumerable: true, value: Object.freeze(codes), writable: false
+});
+
+exports.Deflate = Deflate;
+exports.Inflate = Inflate;
+exports.Gzip = Gzip;
+exports.Gunzip = Gunzip;
+exports.DeflateRaw = DeflateRaw;
+exports.InflateRaw = InflateRaw;
+exports.Unzip = Unzip;
+
+exports.createDeflate = function(o) {
+ return new Deflate(o);
+};
+
+exports.createInflate = function(o) {
+ return new Inflate(o);
+};
+
+exports.createDeflateRaw = function(o) {
+ return new DeflateRaw(o);
+};
+
+exports.createInflateRaw = function(o) {
+ return new InflateRaw(o);
+};
+
+exports.createGzip = function(o) {
+ return new Gzip(o);
+};
+
+exports.createGunzip = function(o) {
+ return new Gunzip(o);
+};
+
+exports.createUnzip = function(o) {
+ return new Unzip(o);
+};
+
+
+// Convenience methods.
+// compress/decompress a string or buffer in one step.
+exports.deflate = function(buffer, opts, callback) {
+ if (typeof opts === 'function') {
+ callback = opts;
+ opts = {};
+ }
+ return zlibBuffer(new Deflate(opts), buffer, callback);
+};
+
+exports.deflateSync = function(buffer, opts) {
+ return zlibBufferSync(new Deflate(opts), buffer);
+};
+
+exports.gzip = function(buffer, opts, callback) {
+ if (typeof opts === 'function') {
+ callback = opts;
+ opts = {};
+ }
+ return zlibBuffer(new Gzip(opts), buffer, callback);
+};
+
+exports.gzipSync = function(buffer, opts) {
+ return zlibBufferSync(new Gzip(opts), buffer);
+};
+
+exports.deflateRaw = function(buffer, opts, callback) {
+ if (typeof opts === 'function') {
+ callback = opts;
+ opts = {};
+ }
+ return zlibBuffer(new DeflateRaw(opts), buffer, callback);
+};
+
+exports.deflateRawSync = function(buffer, opts) {
+ return zlibBufferSync(new DeflateRaw(opts), buffer);
+};
+
+exports.unzip = function(buffer, opts, callback) {
+ if (typeof opts === 'function') {
+ callback = opts;
+ opts = {};
+ }
+ return zlibBuffer(new Unzip(opts), buffer, callback);
+};
+
+exports.unzipSync = function(buffer, opts) {
+ return zlibBufferSync(new Unzip(opts), buffer);
+};
+
+exports.inflate = function(buffer, opts, callback) {
+ if (typeof opts === 'function') {
+ callback = opts;
+ opts = {};
+ }
+ return zlibBuffer(new Inflate(opts), buffer, callback);
+};
+
+exports.inflateSync = function(buffer, opts) {
+ return zlibBufferSync(new Inflate(opts), buffer);
+};
+
+exports.gunzip = function(buffer, opts, callback) {
+ if (typeof opts === 'function') {
+ callback = opts;
+ opts = {};
+ }
+ return zlibBuffer(new Gunzip(opts), buffer, callback);
+};
+
+exports.gunzipSync = function(buffer, opts) {
+ return zlibBufferSync(new Gunzip(opts), buffer);
+};
+
+exports.inflateRaw = function(buffer, opts, callback) {
+ if (typeof opts === 'function') {
+ callback = opts;
+ opts = {};
+ }
+ return zlibBuffer(new InflateRaw(opts), buffer, callback);
+};
+
+exports.inflateRawSync = function(buffer, opts) {
+ return zlibBufferSync(new InflateRaw(opts), buffer);
+};
+
+function zlibBuffer(engine, buffer, callback) {
+ var buffers = [];
+ var nread = 0;
+
+ engine.on('error', onError);
+ engine.on('end', onEnd);
+
+ engine.end(buffer);
+ flow();
+
+ function flow() {
+ var chunk;
+ while (null !== (chunk = engine.read())) {
+ buffers.push(chunk);
+ nread += chunk.length;
+ }
+ engine.once('readable', flow);
+ }
+
+ function onError(err) {
+ engine.removeListener('end', onEnd);
+ engine.removeListener('readable', flow);
+ callback(err);
+ }
+
+ function onEnd() {
+ var buf;
+ var err = null;
+
+ if (nread >= kMaxLength) {
+ err = new RangeError(kRangeErrorMessage);
+ } else {
+ buf = Buffer.concat(buffers, nread);
+ }
+
+ buffers = [];
+ engine.close();
+ callback(err, buf);
+ }
+}
+
+function zlibBufferSync(engine, buffer) {
+ if (typeof buffer === 'string')
+ buffer = Buffer.from(buffer);
+
+ if (!Buffer.isBuffer(buffer))
+ throw new TypeError('Not a string or buffer');
+
+ var flushFlag = engine._finishFlushFlag;
+
+ return engine._processChunk(buffer, flushFlag);
+}
+
+// generic zlib
+// minimal 2-byte header
+function Deflate(opts) {
+ if (!(this instanceof Deflate)) return new Deflate(opts);
+ Zlib.call(this, opts, binding.DEFLATE);
+}
+
+function Inflate(opts) {
+ if (!(this instanceof Inflate)) return new Inflate(opts);
+ Zlib.call(this, opts, binding.INFLATE);
+}
+
+
+// gzip - bigger header, same deflate compression
+function Gzip(opts) {
+ if (!(this instanceof Gzip)) return new Gzip(opts);
+ Zlib.call(this, opts, binding.GZIP);
+}
+
+function Gunzip(opts) {
+ if (!(this instanceof Gunzip)) return new Gunzip(opts);
+ Zlib.call(this, opts, binding.GUNZIP);
+}
+
+
+// raw - no header
+function DeflateRaw(opts) {
+ if (!(this instanceof DeflateRaw)) return new DeflateRaw(opts);
+ Zlib.call(this, opts, binding.DEFLATERAW);
+}
+
+function InflateRaw(opts) {
+ if (!(this instanceof InflateRaw)) return new InflateRaw(opts);
+ Zlib.call(this, opts, binding.INFLATERAW);
+}
+
+
+// auto-detect header.
+function Unzip(opts) {
+ if (!(this instanceof Unzip)) return new Unzip(opts);
+ Zlib.call(this, opts, binding.UNZIP);
+}
+
+function isValidFlushFlag(flag) {
+ return flag === binding.Z_NO_FLUSH ||
+ flag === binding.Z_PARTIAL_FLUSH ||
+ flag === binding.Z_SYNC_FLUSH ||
+ flag === binding.Z_FULL_FLUSH ||
+ flag === binding.Z_FINISH ||
+ flag === binding.Z_BLOCK;
+}
+
+// the Zlib class they all inherit from
+// This thing manages the queue of requests, and returns
+// true or false if there is anything in the queue when
+// you call the .write() method.
+
+function Zlib(opts, mode) {
+ this._opts = opts = opts || {};
+ this._chunkSize = opts.chunkSize || exports.Z_DEFAULT_CHUNK;
+
+ Transform.call(this, opts);
+
+ if (opts.flush && !isValidFlushFlag(opts.flush)) {
+ throw new Error('Invalid flush flag: ' + opts.flush);
+ }
+ if (opts.finishFlush && !isValidFlushFlag(opts.finishFlush)) {
+ throw new Error('Invalid flush flag: ' + opts.finishFlush);
+ }
+
+ this._flushFlag = opts.flush || binding.Z_NO_FLUSH;
+ this._finishFlushFlag = typeof opts.finishFlush !== 'undefined' ?
+ opts.finishFlush : binding.Z_FINISH;
+
+ if (opts.chunkSize) {
+ if (opts.chunkSize < exports.Z_MIN_CHUNK ||
+ opts.chunkSize > exports.Z_MAX_CHUNK) {
+ throw new Error('Invalid chunk size: ' + opts.chunkSize);
+ }
+ }
+
+ if (opts.windowBits) {
+ if (opts.windowBits < exports.Z_MIN_WINDOWBITS ||
+ opts.windowBits > exports.Z_MAX_WINDOWBITS) {
+ throw new Error('Invalid windowBits: ' + opts.windowBits);
+ }
+ }
+
+ if (opts.level) {
+ if (opts.level < exports.Z_MIN_LEVEL ||
+ opts.level > exports.Z_MAX_LEVEL) {
+ throw new Error('Invalid compression level: ' + opts.level);
+ }
+ }
+
+ if (opts.memLevel) {
+ if (opts.memLevel < exports.Z_MIN_MEMLEVEL ||
+ opts.memLevel > exports.Z_MAX_MEMLEVEL) {
+ throw new Error('Invalid memLevel: ' + opts.memLevel);
+ }
+ }
+
+ if (opts.strategy) {
+ if (opts.strategy != exports.Z_FILTERED &&
+ opts.strategy != exports.Z_HUFFMAN_ONLY &&
+ opts.strategy != exports.Z_RLE &&
+ opts.strategy != exports.Z_FIXED &&
+ opts.strategy != exports.Z_DEFAULT_STRATEGY) {
+ throw new Error('Invalid strategy: ' + opts.strategy);
+ }
+ }
+
+ if (opts.dictionary) {
+ if (!Buffer.isBuffer(opts.dictionary)) {
+ throw new Error('Invalid dictionary: it should be a Buffer instance');
+ }
+ }
+
+ this._handle = new binding.Zlib(mode);
+
+ var self = this;
+ this._hadError = false;
+ this._handle.onerror = function(message, errno) {
+ // there is no way to cleanly recover.
+ // continuing only obscures problems.
+ _close(self);
+ self._hadError = true;
+
+ var error = new Error(message);
+ error.errno = errno;
+ error.code = exports.codes[errno];
+ self.emit('error', error);
+ };
+
+ var level = exports.Z_DEFAULT_COMPRESSION;
+ if (typeof opts.level === 'number') level = opts.level;
+
+ var strategy = exports.Z_DEFAULT_STRATEGY;
+ if (typeof opts.strategy === 'number') strategy = opts.strategy;
+
+ this._handle.init(opts.windowBits || exports.Z_DEFAULT_WINDOWBITS,
+ level,
+ opts.memLevel || exports.Z_DEFAULT_MEMLEVEL,
+ strategy,
+ opts.dictionary);
+
+ this._buffer = Buffer.allocUnsafe(this._chunkSize);
+ this._offset = 0;
+ this._level = level;
+ this._strategy = strategy;
+
+ this.once('end', this.close);
+
+ Object.defineProperty(this, '_closed', {
+ get: () => { return !this._handle; },
+ configurable: true,
+ enumerable: true
+ });
+}
+
+util.inherits(Zlib, Transform);
+
+Zlib.prototype.params = function(level, strategy, callback) {
+ if (level < exports.Z_MIN_LEVEL ||
+ level > exports.Z_MAX_LEVEL) {
+ throw new RangeError('Invalid compression level: ' + level);
+ }
+ if (strategy != exports.Z_FILTERED &&
+ strategy != exports.Z_HUFFMAN_ONLY &&
+ strategy != exports.Z_RLE &&
+ strategy != exports.Z_FIXED &&
+ strategy != exports.Z_DEFAULT_STRATEGY) {
+ throw new TypeError('Invalid strategy: ' + strategy);
+ }
+
+ if (this._level !== level || this._strategy !== strategy) {
+ var self = this;
+ this.flush(binding.Z_SYNC_FLUSH, function() {
+ assert(self._handle, 'zlib binding closed');
+ self._handle.params(level, strategy);
+ if (!self._hadError) {
+ self._level = level;
+ self._strategy = strategy;
+ if (callback) callback();
+ }
+ });
+ } else {
+ process.nextTick(callback);
+ }
+};
+
+Zlib.prototype.reset = function() {
+ assert(this._handle, 'zlib binding closed');
+ return this._handle.reset();
+};
+
+// This is the _flush function called by the transform class,
+// internally, when the last chunk has been written.
+Zlib.prototype._flush = function(callback) {
+ this._transform(Buffer.alloc(0), '', callback);
+};
+
+Zlib.prototype.flush = function(kind, callback) {
+ var ws = this._writableState;
+
+ if (typeof kind === 'function' || (kind === undefined && !callback)) {
+ callback = kind;
+ kind = binding.Z_FULL_FLUSH;
+ }
+
+ if (ws.ended) {
+ if (callback)
+ process.nextTick(callback);
+ } else if (ws.ending) {
+ if (callback)
+ this.once('end', callback);
+ } else if (ws.needDrain) {
+ if (callback) {
+ this.once('drain', () => this.flush(kind, callback));
+ }
+ } else {
+ this._flushFlag = kind;
+ this.write(Buffer.alloc(0), '', callback);
+ }
+};
+
+Zlib.prototype.close = function(callback) {
+ _close(this, callback);
+ process.nextTick(emitCloseNT, this);
+};
+
+function _close(engine, callback) {
+ if (callback)
+ process.nextTick(callback);
+
+ // Caller may invoke .close after a zlib error (which will null _handle).
+ if (!engine._handle)
+ return;
+
+ engine._handle.close();
+ engine._handle = null;
+}
+
+function emitCloseNT(self) {
+ self.emit('close');
+}
+
+Zlib.prototype._transform = function(chunk, encoding, cb) {
+ var flushFlag;
+ var ws = this._writableState;
+ var ending = ws.ending || ws.ended;
+ var last = ending && (!chunk || ws.length === chunk.length);
+
+ if (chunk !== null && !Buffer.isBuffer(chunk))
+ return cb(new Error('invalid input'));
+
+ if (!this._handle)
+ return cb(new Error('zlib binding closed'));
+
+ // If it's the last chunk, or a final flush, we use the Z_FINISH flush flag
+ // (or whatever flag was provided using opts.finishFlush).
+ // If it's explicitly flushing at some other time, then we use
+ // Z_FULL_FLUSH. Otherwise, use Z_NO_FLUSH for maximum compression
+ // goodness.
+ if (last)
+ flushFlag = this._finishFlushFlag;
+ else {
+ flushFlag = this._flushFlag;
+ // once we've flushed the last of the queue, stop flushing and
+ // go back to the normal behavior.
+ if (chunk.length >= ws.length) {
+ this._flushFlag = this._opts.flush || binding.Z_NO_FLUSH;
+ }
+ }
+
+ this._processChunk(chunk, flushFlag, cb);
+};
+
+Zlib.prototype._processChunk = function(chunk, flushFlag, cb) {
+ var availInBefore = chunk && chunk.length;
+ var availOutBefore = this._chunkSize - this._offset;
+ var inOff = 0;
+
+ var self = this;
+
+ var async = typeof cb === 'function';
+
+ if (!async) {
+ var buffers = [];
+ var nread = 0;
+
+ var error;
+ this.on('error', function(er) {
+ error = er;
+ });
+
+ assert(this._handle, 'zlib binding closed');
+ do {
+ var res = this._handle.writeSync(flushFlag,
+ chunk, // in
+ inOff, // in_off
+ availInBefore, // in_len
+ this._buffer, // out
+ this._offset, //out_off
+ availOutBefore); // out_len
+ } while (!this._hadError && callback(res[0], res[1]));
+
+ if (this._hadError) {
+ throw error;
+ }
+
+ if (nread >= kMaxLength) {
+ _close(this);
+ throw new RangeError(kRangeErrorMessage);
+ }
+
+ var buf = Buffer.concat(buffers, nread);
+ _close(this);
+
+ return buf;
+ }
+
+ assert(this._handle, 'zlib binding closed');
+ var req = this._handle.write(flushFlag,
+ chunk, // in
+ inOff, // in_off
+ availInBefore, // in_len
+ this._buffer, // out
+ this._offset, //out_off
+ availOutBefore); // out_len
+
+ req.buffer = chunk;
+ req.callback = callback;
+
+ function callback(availInAfter, availOutAfter) {
+ // When the callback is used in an async write, the callback's
+ // context is the `req` object that was created. The req object
+ // is === this._handle, and that's why it's important to null
+ // out the values after they are done being used. `this._handle`
+ // can stay in memory longer than the callback and buffer are needed.
+ if (this) {
+ this.buffer = null;
+ this.callback = null;
+ }
+
+ if (self._hadError)
+ return;
+
+ var have = availOutBefore - availOutAfter;
+ assert(have >= 0, 'have should not go down');
+
+ if (have > 0) {
+ var out = self._buffer.slice(self._offset, self._offset + have);
+ self._offset += have;
+ // serve some output to the consumer.
+ if (async) {
+ self.push(out);
+ } else {
+ buffers.push(out);
+ nread += out.length;
+ }
+ }
+
+ // exhausted the output buffer, or used all the input create a new one.
+ if (availOutAfter === 0 || self._offset >= self._chunkSize) {
+ availOutBefore = self._chunkSize;
+ self._offset = 0;
+ self._buffer = Buffer.allocUnsafe(self._chunkSize);
+ }
+
+ if (availOutAfter === 0) {
+ // Not actually done. Need to reprocess.
+ // Also, update the availInBefore to the availInAfter value,
+ // so that if we have to hit it a third (fourth, etc.) time,
+ // it'll have the correct byte counts.
+ inOff += (availInBefore - availInAfter);
+ availInBefore = availInAfter;
+
+ if (!async)
+ return true;
+
+ var newReq = self._handle.write(flushFlag,
+ chunk,
+ inOff,
+ availInBefore,
+ self._buffer,
+ self._offset,
+ self._chunkSize);
+ newReq.callback = callback; // this same function
+ newReq.buffer = chunk;
+ return;
+ }
+
+ if (!async)
+ return false;
+
+ // finished with the chunk.
+ cb();
+ }
+};
+
+util.inherits(Deflate, Zlib);
+util.inherits(Inflate, Zlib);
+util.inherits(Gzip, Zlib);
+util.inherits(Gunzip, Zlib);
+util.inherits(DeflateRaw, Zlib);
+util.inherits(InflateRaw, Zlib);
+util.inherits(Unzip, Zlib);