419 lines
18 KiB
JavaScript
419 lines
18 KiB
JavaScript
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var fs = require("fs");
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var Transform = require("stream").Transform;
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var PassThrough = require("stream").PassThrough;
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var zlib = require("zlib");
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var util = require("util");
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var EventEmitter = require("events").EventEmitter;
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var crc32 = require("buffer-crc32");
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exports.ZipFile = ZipFile;
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exports.dateToDosDateTime = dateToDosDateTime;
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util.inherits(ZipFile, EventEmitter);
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function ZipFile() {
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this.outputStream = new PassThrough();
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this.entries = [];
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this.outputStreamCursor = 0;
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this.ended = false; // .end() sets this
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this.allDone = false; // set when we've written the last bytes
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}
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ZipFile.prototype.addFile = function(realPath, metadataPath, options) {
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var self = this;
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metadataPath = validateMetadataPath(metadataPath, false);
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if (options == null) options = {};
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var entry = new Entry(metadataPath, false, options);
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self.entries.push(entry);
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fs.stat(realPath, function(err, stats) {
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if (err) return self.emit("error", err);
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if (!stats.isFile()) return self.emit("error", new Error("not a file: " + realPath));
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entry.uncompressedSize = stats.size;
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if (options.mtime == null) entry.setLastModDate(stats.mtime);
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if (options.mode == null) entry.setFileAttributesMode(stats.mode);
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entry.setFileDataPumpFunction(function() {
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var readStream = fs.createReadStream(realPath);
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entry.state = Entry.FILE_DATA_IN_PROGRESS;
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readStream.on("error", function(err) {
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self.emit("error", err);
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});
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pumpFileDataReadStream(self, entry, readStream);
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});
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pumpEntries(self);
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});
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};
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ZipFile.prototype.addReadStream = function(readStream, metadataPath, options) {
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var self = this;
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metadataPath = validateMetadataPath(metadataPath, false);
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if (options == null) options = {};
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var entry = new Entry(metadataPath, false, options);
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self.entries.push(entry);
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entry.setFileDataPumpFunction(function() {
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entry.state = Entry.FILE_DATA_IN_PROGRESS;
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pumpFileDataReadStream(self, entry, readStream);
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});
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pumpEntries(self);
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};
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ZipFile.prototype.addBuffer = function(buffer, metadataPath, options) {
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var self = this;
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metadataPath = validateMetadataPath(metadataPath, false);
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if (options == null) options = {};
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if (options.size != null) throw new Error("options.size not allowed");
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var entry = new Entry(metadataPath, false, options);
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entry.uncompressedSize = buffer.length;
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entry.crc32 = crc32.unsigned(buffer);
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entry.crcAndFileSizeKnown = true;
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self.entries.push(entry);
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if (!entry.compress) {
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setCompressedBuffer(buffer);
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} else {
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zlib.deflateRaw(buffer, function(err, compressedBuffer) {
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setCompressedBuffer(compressedBuffer);
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});
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}
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function setCompressedBuffer(compressedBuffer) {
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entry.compressedSize = compressedBuffer.length;
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entry.setFileDataPumpFunction(function() {
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writeToOutputStream(self, compressedBuffer);
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writeToOutputStream(self, entry.getFileDescriptor());
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entry.state = Entry.FILE_DATA_DONE;
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// don't call pumpEntries() recursively.
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// (also, don't call process.nextTick recursively.)
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setImmediate(function() {
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pumpEntries(self);
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});
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});
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pumpEntries(self);
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}
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};
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ZipFile.prototype.addEmptyDirectory = function(metadataPath, options) {
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var self = this;
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metadataPath = validateMetadataPath(metadataPath, true);
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if (options == null) options = {};
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if (options.size != null) throw new Error("options.size not allowed");
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if (options.compress != null) throw new Error("options.compress not allowed");
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var entry = new Entry(metadataPath, true, options);
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self.entries.push(entry);
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entry.setFileDataPumpFunction(function() {
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writeToOutputStream(self, entry.getFileDescriptor());
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entry.state = Entry.FILE_DATA_DONE;
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pumpEntries(self);
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});
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pumpEntries(self);
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};
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ZipFile.prototype.end = function(finalSizeCallback) {
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if (this.ended) return;
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this.ended = true;
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this.finalSizeCallback = finalSizeCallback;
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pumpEntries(this);
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};
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function writeToOutputStream(self, buffer) {
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self.outputStream.write(buffer);
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self.outputStreamCursor += buffer.length;
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}
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function pumpFileDataReadStream(self, entry, readStream) {
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var crc32Watcher = new Crc32Watcher();
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var uncompressedSizeCounter = new ByteCounter();
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var compressor = entry.compress ? new zlib.DeflateRaw() : new PassThrough();
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var compressedSizeCounter = new ByteCounter();
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readStream.pipe(crc32Watcher)
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.pipe(uncompressedSizeCounter)
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.pipe(compressor)
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.pipe(compressedSizeCounter)
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.pipe(self.outputStream, {end: false});
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compressedSizeCounter.on("end", function() {
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entry.crc32 = crc32Watcher.crc32;
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if (entry.uncompressedSize == null) {
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entry.uncompressedSize = uncompressedSizeCounter.byteCount;
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} else {
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if (entry.uncompressedSize !== uncompressedSizeCounter.byteCount) return self.emit("error", new Error("file data stream has unexpected number of bytes"));
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}
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entry.compressedSize = compressedSizeCounter.byteCount;
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self.outputStreamCursor += entry.compressedSize;
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writeToOutputStream(self, entry.getFileDescriptor());
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entry.state = Entry.FILE_DATA_DONE;
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pumpEntries(self);
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});
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}
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function pumpEntries(self) {
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if (self.allDone) return;
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// first check if finalSize is finally known
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if (self.ended && self.finalSizeCallback != null) {
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var finalSize = calculateFinalSize(self);
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if (finalSize != null) {
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// we have an answer
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self.finalSizeCallback(finalSize);
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self.finalSizeCallback = null;
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}
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}
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// pump entries
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var entry = getFirstNotDoneEntry();
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function getFirstNotDoneEntry() {
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for (var i = 0; i < self.entries.length; i++) {
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var entry = self.entries[i];
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if (entry.state < Entry.FILE_DATA_DONE) return entry;
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}
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return null;
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}
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if (entry != null) {
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// this entry is not done yet
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if (entry.state < Entry.READY_TO_PUMP_FILE_DATA) return; // input file not open yet
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if (entry.state === Entry.FILE_DATA_IN_PROGRESS) return; // we'll get there
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// start with local file header
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entry.relativeOffsetOfLocalHeader = self.outputStreamCursor;
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var localFileHeader = entry.getLocalFileHeader();
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writeToOutputStream(self, localFileHeader);
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entry.doFileDataPump();
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} else {
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// all cought up on writing entries
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if (self.ended) {
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// head for the exit
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self.offsetOfStartOfCentralDirectory = self.outputStreamCursor;
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self.entries.forEach(function(entry) {
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var centralDirectoryRecord = entry.getCentralDirectoryRecord();
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writeToOutputStream(self, centralDirectoryRecord);
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});
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writeToOutputStream(self, getEndOfCentralDirectoryRecord(self));
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self.outputStream.end();
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self.allDone = true;
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}
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}
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}
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function calculateFinalSize(self) {
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var result = 0;
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for (var i = 0; i < self.entries.length; i++) {
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var entry = self.entries[i];
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// compression is too hard to predict
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if (entry.compress) return -1;
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if (entry.state >= Entry.READY_TO_PUMP_FILE_DATA) {
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// if addReadStream was called without providing the size, we can't predict the final size
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if (entry.uncompressedSize == null) return -1;
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} else {
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// if we're still waiting for fs.stat, we might learn the size someday
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if (entry.uncompressedSize == null) return null;
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}
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result += LOCAL_FILE_HEADER_FIXED_SIZE + entry.utf8FileName.length +
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entry.uncompressedSize +
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CENTRAL_DIRECTORY_RECORD_FIXED_SIZE + entry.utf8FileName.length;
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if (!entry.crcAndFileSizeKnown) result += FILE_DESCRIPTOR_SIZE;
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}
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result += END_OF_CENTRAL_DIRECTORY_RECORD_SIZE;
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return result;
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}
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var END_OF_CENTRAL_DIRECTORY_RECORD_SIZE = 22;
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function getEndOfCentralDirectoryRecord(self) {
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var buffer = new Buffer(END_OF_CENTRAL_DIRECTORY_RECORD_SIZE);
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buffer.writeUInt32LE(0x06054b50, 0); // end of central dir signature 4 bytes (0x06054b50)
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buffer.writeUInt16LE(0, 4); // number of this disk 2 bytes
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buffer.writeUInt16LE(0, 6); // number of the disk with the start of the central directory 2 bytes
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buffer.writeUInt16LE(self.entries.length, 8); // total number of entries in the central directory on this disk 2 bytes
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buffer.writeUInt16LE(self.entries.length, 10); // total number of entries in the central directory 2 bytes
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buffer.writeUInt32LE(self.outputStreamCursor - self.offsetOfStartOfCentralDirectory, 12); // size of the central directory 4 bytes
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buffer.writeUInt32LE(self.offsetOfStartOfCentralDirectory, 16); // offset of start of central directory with respect to the starting disk number 4 bytes
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buffer.writeUInt16LE(0, 20); // .ZIP file comment length 2 bytes
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/* no comment */ // .ZIP file comment (variable size)
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return buffer;
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}
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function validateMetadataPath(metadataPath, isDirectory) {
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if (metadataPath === "") throw new Error("empty metadataPath");
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metadataPath = metadataPath.replace(/\\/g, "/");
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if (/^[a-zA-Z]:/.test(metadataPath) || /^\//.test(metadataPath)) throw new Error("absolute path: " + metadataPath);
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if (metadataPath.split("/").indexOf("..") !== -1) throw new Error("invalid relative path: " + metadataPath);
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var looksLikeDirectory = /\/$/.test(metadataPath);
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if (isDirectory) {
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// append a trailing '/' if necessary.
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if (!looksLikeDirectory) metadataPath += "/";
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} else {
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if (looksLikeDirectory) throw new Error("file path cannot end with '/': " + metadataPath);
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}
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return metadataPath;
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}
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// this class is not part of the public API
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function Entry(metadataPath, isDirectory, options) {
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this.utf8FileName = new Buffer(metadataPath);
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if (this.utf8FileName.length > 0xffff) throw new Error("utf8 file name too long. " + utf8FileName.length + " > " + 0xffff);
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this.isDirectory = isDirectory;
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this.state = Entry.WAITING_FOR_METADATA;
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this.setLastModDate(options.mtime != null ? options.mtime : new Date());
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if (options.mode != null) {
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this.setFileAttributesMode(options.mode);
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} else {
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this.setFileAttributesMode(isDirectory ? 040775 : 0100664);
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}
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if (isDirectory) {
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this.crcAndFileSizeKnown = true;
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this.crc32 = 0;
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this.uncompressedSize = 0;
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this.compressedSize = 0;
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} else {
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// unknown so far
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this.crcAndFileSizeKnown = false;
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this.crc32 = null;
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this.uncompressedSize = null;
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this.compressedSize = null;
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if (options.size != null) this.uncompressedSize = options.size;
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}
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if (isDirectory) {
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this.compress = false;
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} else {
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this.compress = true; // default
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if (options.compress != null) this.compress = !!options.compress;
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}
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}
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Entry.WAITING_FOR_METADATA = 0;
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Entry.READY_TO_PUMP_FILE_DATA = 1;
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Entry.FILE_DATA_IN_PROGRESS = 2;
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Entry.FILE_DATA_DONE = 3;
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Entry.prototype.setLastModDate = function(date) {
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var dosDateTime = dateToDosDateTime(date);
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this.lastModFileTime = dosDateTime.time;
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this.lastModFileDate = dosDateTime.date;
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};
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Entry.prototype.setFileAttributesMode = function(mode) {
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if ((mode & 0xffff) !== mode) throw new Error("invalid mode. expected: 0 <= " + mode + " <= " + 0xffff);
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// http://unix.stackexchange.com/questions/14705/the-zip-formats-external-file-attribute/14727#14727
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this.externalFileAttributes = (mode << 16) >>> 0;
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};
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// doFileDataPump() should not call pumpEntries() directly. see issue #9.
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Entry.prototype.setFileDataPumpFunction = function(doFileDataPump) {
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this.doFileDataPump = doFileDataPump;
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this.state = Entry.READY_TO_PUMP_FILE_DATA;
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};
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var LOCAL_FILE_HEADER_FIXED_SIZE = 30;
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// this version enables utf8 filename encoding
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var VERSION_NEEDED_TO_EXTRACT = 0x0014;
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// this is the "version made by" reported by linux info-zip.
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var VERSION_MADE_BY_INFO_ZIP = 0x031e;
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var FILE_NAME_IS_UTF8 = 1 << 11;
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var UNKNOWN_CRC32_AND_FILE_SIZES = 1 << 3;
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Entry.prototype.getLocalFileHeader = function() {
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var crc32 = 0;
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var compressedSize = 0;
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var uncompressedSize = 0;
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if (this.crcAndFileSizeKnown) {
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crc32 = this.crc32;
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compressedSize = this.compressedSize;
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uncompressedSize = this.uncompressedSize;
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}
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var fixedSizeStuff = new Buffer(LOCAL_FILE_HEADER_FIXED_SIZE);
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var generalPurposeBitFlag = FILE_NAME_IS_UTF8;
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if (!this.crcAndFileSizeKnown) generalPurposeBitFlag |= UNKNOWN_CRC32_AND_FILE_SIZES;
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fixedSizeStuff.writeUInt32LE(0x04034b50, 0); // local file header signature 4 bytes (0x04034b50)
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fixedSizeStuff.writeUInt16LE(VERSION_NEEDED_TO_EXTRACT, 4); // version needed to extract 2 bytes
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fixedSizeStuff.writeUInt16LE(generalPurposeBitFlag, 6); // general purpose bit flag 2 bytes
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fixedSizeStuff.writeUInt16LE(this.getCompressionMethod(), 8); // compression method 2 bytes
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fixedSizeStuff.writeUInt16LE(this.lastModFileTime, 10); // last mod file time 2 bytes
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fixedSizeStuff.writeUInt16LE(this.lastModFileDate, 12); // last mod file date 2 bytes
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fixedSizeStuff.writeUInt32LE(crc32, 14); // crc-32 4 bytes
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fixedSizeStuff.writeUInt32LE(compressedSize, 18); // compressed size 4 bytes
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fixedSizeStuff.writeUInt32LE(uncompressedSize, 22); // uncompressed size 4 bytes
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fixedSizeStuff.writeUInt16LE(this.utf8FileName.length, 26); // file name length 2 bytes
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fixedSizeStuff.writeUInt16LE(0, 28); // extra field length 2 bytes
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return Buffer.concat([
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fixedSizeStuff,
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this.utf8FileName, // file name (variable size)
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/* no extra fields */ // extra field (variable size)
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]);
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};
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var FILE_DESCRIPTOR_SIZE = 16
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Entry.prototype.getFileDescriptor = function() {
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if (this.crcAndFileSizeKnown) {
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// MAC's Archive Utility requires this not be present unless we set general purpose bit 3
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return new Buffer(0);
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}
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var buffer = new Buffer(FILE_DESCRIPTOR_SIZE);
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buffer.writeUInt32LE(0x08074b50, 0); // optional signature (required according to Archive Utility)
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buffer.writeUInt32LE(this.crc32, 4); // crc-32 4 bytes
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buffer.writeUInt32LE(this.compressedSize, 8); // compressed size 4 bytes
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buffer.writeUInt32LE(this.uncompressedSize, 12); // uncompressed size 4 bytes
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return buffer;
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};
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var CENTRAL_DIRECTORY_RECORD_FIXED_SIZE = 46;
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Entry.prototype.getCentralDirectoryRecord = function() {
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var fixedSizeStuff = new Buffer(CENTRAL_DIRECTORY_RECORD_FIXED_SIZE);
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var generalPurposeBitFlag = FILE_NAME_IS_UTF8;
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if (!this.crcAndFileSizeKnown) generalPurposeBitFlag |= UNKNOWN_CRC32_AND_FILE_SIZES;
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fixedSizeStuff.writeUInt32LE(0x02014b50, 0); // central file header signature 4 bytes (0x02014b50)
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fixedSizeStuff.writeUInt16LE(VERSION_MADE_BY_INFO_ZIP, 4); // version made by 2 bytes
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fixedSizeStuff.writeUInt16LE(VERSION_NEEDED_TO_EXTRACT, 6); // version needed to extract 2 bytes
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fixedSizeStuff.writeUInt16LE(generalPurposeBitFlag, 8); // general purpose bit flag 2 bytes
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fixedSizeStuff.writeUInt16LE(this.getCompressionMethod(), 10); // compression method 2 bytes
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fixedSizeStuff.writeUInt16LE(this.lastModFileTime, 12); // last mod file time 2 bytes
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fixedSizeStuff.writeUInt16LE(this.lastModFileDate, 14); // last mod file date 2 bytes
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fixedSizeStuff.writeUInt32LE(this.crc32, 16); // crc-32 4 bytes
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fixedSizeStuff.writeUInt32LE(this.compressedSize, 20); // compressed size 4 bytes
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fixedSizeStuff.writeUInt32LE(this.uncompressedSize, 24); // uncompressed size 4 bytes
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fixedSizeStuff.writeUInt16LE(this.utf8FileName.length, 28); // file name length 2 bytes
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fixedSizeStuff.writeUInt16LE(0, 30); // extra field length 2 bytes
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fixedSizeStuff.writeUInt16LE(0, 32); // file comment length 2 bytes
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fixedSizeStuff.writeUInt16LE(0, 34); // disk number start 2 bytes
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fixedSizeStuff.writeUInt16LE(0, 36); // internal file attributes 2 bytes
|
||
|
fixedSizeStuff.writeUInt32LE(this.externalFileAttributes, 38); // external file attributes 4 bytes
|
||
|
fixedSizeStuff.writeUInt32LE(this.relativeOffsetOfLocalHeader, 42); // relative offset of local header 4 bytes
|
||
|
return Buffer.concat([
|
||
|
fixedSizeStuff,
|
||
|
this.utf8FileName, // file name (variable size)
|
||
|
/* no extra fields */ // extra field (variable size)
|
||
|
/* empty comment */ // file comment (variable size)
|
||
|
]);
|
||
|
};
|
||
|
Entry.prototype.getCompressionMethod = function() {
|
||
|
var NO_COMPRESSION = 0;
|
||
|
var DEFLATE_COMPRESSION = 8;
|
||
|
return this.compress ? DEFLATE_COMPRESSION : NO_COMPRESSION;
|
||
|
};
|
||
|
|
||
|
function dateToDosDateTime(jsDate) {
|
||
|
var date = 0;
|
||
|
date |= jsDate.getDate() & 0x1f; // 1-31
|
||
|
date |= ((jsDate.getMonth() + 1) & 0xf) << 5; // 0-11, 1-12
|
||
|
date |= ((jsDate.getFullYear() - 1980) & 0x7f) << 9; // 0-128, 1980-2108
|
||
|
|
||
|
var time = 0;
|
||
|
time |= Math.floor(jsDate.getSeconds() / 2); // 0-59, 0-29 (lose odd numbers)
|
||
|
time |= (jsDate.getMinutes() & 0x3f) << 5; // 0-59
|
||
|
time |= (jsDate.getHours() & 0x1f) << 11; // 0-23
|
||
|
|
||
|
return {date: date, time: time};
|
||
|
}
|
||
|
|
||
|
function defaultCallback(err) {
|
||
|
if (err) throw err;
|
||
|
}
|
||
|
|
||
|
util.inherits(ByteCounter, Transform);
|
||
|
function ByteCounter(options) {
|
||
|
Transform.call(this, options);
|
||
|
this.byteCount = 0;
|
||
|
}
|
||
|
ByteCounter.prototype._transform = function(chunk, encoding, cb) {
|
||
|
this.byteCount += chunk.length;
|
||
|
cb(null, chunk);
|
||
|
};
|
||
|
|
||
|
util.inherits(Crc32Watcher, Transform);
|
||
|
function Crc32Watcher(options) {
|
||
|
Transform.call(this, options);
|
||
|
this.crc32 = 0;
|
||
|
}
|
||
|
Crc32Watcher.prototype._transform = function(chunk, encoding, cb) {
|
||
|
this.crc32 = crc32.unsigned(chunk, this.crc32);
|
||
|
cb(null, chunk);
|
||
|
};
|