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Diffstat (limited to 'client/node_modules/yauzl/index.js')
| -rw-r--r-- | client/node_modules/yauzl/index.js | 796 |
1 files changed, 796 insertions, 0 deletions
diff --git a/client/node_modules/yauzl/index.js b/client/node_modules/yauzl/index.js new file mode 100644 index 0000000..cf5d70d --- /dev/null +++ b/client/node_modules/yauzl/index.js @@ -0,0 +1,796 @@ +var fs = require("fs"); +var zlib = require("zlib"); +var fd_slicer = require("fd-slicer"); +var crc32 = require("buffer-crc32"); +var util = require("util"); +var EventEmitter = require("events").EventEmitter; +var Transform = require("stream").Transform; +var PassThrough = require("stream").PassThrough; +var Writable = require("stream").Writable; + +exports.open = open; +exports.fromFd = fromFd; +exports.fromBuffer = fromBuffer; +exports.fromRandomAccessReader = fromRandomAccessReader; +exports.dosDateTimeToDate = dosDateTimeToDate; +exports.validateFileName = validateFileName; +exports.ZipFile = ZipFile; +exports.Entry = Entry; +exports.RandomAccessReader = RandomAccessReader; + +function open(path, options, callback) { + if (typeof options === "function") { + callback = options; + options = null; + } + if (options == null) options = {}; + if (options.autoClose == null) options.autoClose = true; + if (options.lazyEntries == null) options.lazyEntries = false; + if (options.decodeStrings == null) options.decodeStrings = true; + if (options.validateEntrySizes == null) options.validateEntrySizes = true; + if (options.strictFileNames == null) options.strictFileNames = false; + if (callback == null) callback = defaultCallback; + fs.open(path, "r", function(err, fd) { + if (err) return callback(err); + fromFd(fd, options, function(err, zipfile) { + if (err) fs.close(fd, defaultCallback); + callback(err, zipfile); + }); + }); +} + +function fromFd(fd, options, callback) { + if (typeof options === "function") { + callback = options; + options = null; + } + if (options == null) options = {}; + if (options.autoClose == null) options.autoClose = false; + if (options.lazyEntries == null) options.lazyEntries = false; + if (options.decodeStrings == null) options.decodeStrings = true; + if (options.validateEntrySizes == null) options.validateEntrySizes = true; + if (options.strictFileNames == null) options.strictFileNames = false; + if (callback == null) callback = defaultCallback; + fs.fstat(fd, function(err, stats) { + if (err) return callback(err); + var reader = fd_slicer.createFromFd(fd, {autoClose: true}); + fromRandomAccessReader(reader, stats.size, options, callback); + }); +} + +function fromBuffer(buffer, options, callback) { + if (typeof options === "function") { + callback = options; + options = null; + } + if (options == null) options = {}; + options.autoClose = false; + if (options.lazyEntries == null) options.lazyEntries = false; + if (options.decodeStrings == null) options.decodeStrings = true; + if (options.validateEntrySizes == null) options.validateEntrySizes = true; + if (options.strictFileNames == null) options.strictFileNames = false; + // limit the max chunk size. see https://github.com/thejoshwolfe/yauzl/issues/87 + var reader = fd_slicer.createFromBuffer(buffer, {maxChunkSize: 0x10000}); + fromRandomAccessReader(reader, buffer.length, options, callback); +} + +function fromRandomAccessReader(reader, totalSize, options, callback) { + if (typeof options === "function") { + callback = options; + options = null; + } + if (options == null) options = {}; + if (options.autoClose == null) options.autoClose = true; + if (options.lazyEntries == null) options.lazyEntries = false; + if (options.decodeStrings == null) options.decodeStrings = true; + var decodeStrings = !!options.decodeStrings; + if (options.validateEntrySizes == null) options.validateEntrySizes = true; + if (options.strictFileNames == null) options.strictFileNames = false; + if (callback == null) callback = defaultCallback; + if (typeof totalSize !== "number") throw new Error("expected totalSize parameter to be a number"); + if (totalSize > Number.MAX_SAFE_INTEGER) { + throw new Error("zip file too large. only file sizes up to 2^52 are supported due to JavaScript's Number type being an IEEE 754 double."); + } + + // the matching unref() call is in zipfile.close() + reader.ref(); + + // eocdr means End of Central Directory Record. + // search backwards for the eocdr signature. + // the last field of the eocdr is a variable-length comment. + // the comment size is encoded in a 2-byte field in the eocdr, which we can't find without trudging backwards through the comment to find it. + // as a consequence of this design decision, it's possible to have ambiguous zip file metadata if a coherent eocdr was in the comment. + // we search backwards for a eocdr signature, and hope that whoever made the zip file was smart enough to forbid the eocdr signature in the comment. + var eocdrWithoutCommentSize = 22; + var maxCommentSize = 0xffff; // 2-byte size + var bufferSize = Math.min(eocdrWithoutCommentSize + maxCommentSize, totalSize); + var buffer = newBuffer(bufferSize); + var bufferReadStart = totalSize - buffer.length; + readAndAssertNoEof(reader, buffer, 0, bufferSize, bufferReadStart, function(err) { + if (err) return callback(err); + for (var i = bufferSize - eocdrWithoutCommentSize; i >= 0; i -= 1) { + if (buffer.readUInt32LE(i) !== 0x06054b50) continue; + // found eocdr + var eocdrBuffer = buffer.slice(i); + + // 0 - End of central directory signature = 0x06054b50 + // 4 - Number of this disk + var diskNumber = eocdrBuffer.readUInt16LE(4); + if (diskNumber !== 0) { + return callback(new Error("multi-disk zip files are not supported: found disk number: " + diskNumber)); + } + // 6 - Disk where central directory starts + // 8 - Number of central directory records on this disk + // 10 - Total number of central directory records + var entryCount = eocdrBuffer.readUInt16LE(10); + // 12 - Size of central directory (bytes) + // 16 - Offset of start of central directory, relative to start of archive + var centralDirectoryOffset = eocdrBuffer.readUInt32LE(16); + // 20 - Comment length + var commentLength = eocdrBuffer.readUInt16LE(20); + var expectedCommentLength = eocdrBuffer.length - eocdrWithoutCommentSize; + if (commentLength !== expectedCommentLength) { + return callback(new Error("invalid comment length. expected: " + expectedCommentLength + ". found: " + commentLength)); + } + // 22 - Comment + // the encoding is always cp437. + var comment = decodeStrings ? decodeBuffer(eocdrBuffer, 22, eocdrBuffer.length, false) + : eocdrBuffer.slice(22); + + if (!(entryCount === 0xffff || centralDirectoryOffset === 0xffffffff)) { + return callback(null, new ZipFile(reader, centralDirectoryOffset, totalSize, entryCount, comment, options.autoClose, options.lazyEntries, decodeStrings, options.validateEntrySizes, options.strictFileNames)); + } + + // ZIP64 format + + // ZIP64 Zip64 end of central directory locator + var zip64EocdlBuffer = newBuffer(20); + var zip64EocdlOffset = bufferReadStart + i - zip64EocdlBuffer.length; + readAndAssertNoEof(reader, zip64EocdlBuffer, 0, zip64EocdlBuffer.length, zip64EocdlOffset, function(err) { + if (err) return callback(err); + + // 0 - zip64 end of central dir locator signature = 0x07064b50 + if (zip64EocdlBuffer.readUInt32LE(0) !== 0x07064b50) { + return callback(new Error("invalid zip64 end of central directory locator signature")); + } + // 4 - number of the disk with the start of the zip64 end of central directory + // 8 - relative offset of the zip64 end of central directory record + var zip64EocdrOffset = readUInt64LE(zip64EocdlBuffer, 8); + // 16 - total number of disks + + // ZIP64 end of central directory record + var zip64EocdrBuffer = newBuffer(56); + readAndAssertNoEof(reader, zip64EocdrBuffer, 0, zip64EocdrBuffer.length, zip64EocdrOffset, function(err) { + if (err) return callback(err); + + // 0 - zip64 end of central dir signature 4 bytes (0x06064b50) + if (zip64EocdrBuffer.readUInt32LE(0) !== 0x06064b50) { + return callback(new Error("invalid zip64 end of central directory record signature")); + } + // 4 - size of zip64 end of central directory record 8 bytes + // 12 - version made by 2 bytes + // 14 - version needed to extract 2 bytes + // 16 - number of this disk 4 bytes + // 20 - number of the disk with the start of the central directory 4 bytes + // 24 - total number of entries in the central directory on this disk 8 bytes + // 32 - total number of entries in the central directory 8 bytes + entryCount = readUInt64LE(zip64EocdrBuffer, 32); + // 40 - size of the central directory 8 bytes + // 48 - offset of start of central directory with respect to the starting disk number 8 bytes + centralDirectoryOffset = readUInt64LE(zip64EocdrBuffer, 48); + // 56 - zip64 extensible data sector (variable size) + return callback(null, new ZipFile(reader, centralDirectoryOffset, totalSize, entryCount, comment, options.autoClose, options.lazyEntries, decodeStrings, options.validateEntrySizes, options.strictFileNames)); + }); + }); + return; + } + callback(new Error("end of central directory record signature not found")); + }); +} + +util.inherits(ZipFile, EventEmitter); +function ZipFile(reader, centralDirectoryOffset, fileSize, entryCount, comment, autoClose, lazyEntries, decodeStrings, validateEntrySizes, strictFileNames) { + var self = this; + EventEmitter.call(self); + self.reader = reader; + // forward close events + self.reader.on("error", function(err) { + // error closing the fd + emitError(self, err); + }); + self.reader.once("close", function() { + self.emit("close"); + }); + self.readEntryCursor = centralDirectoryOffset; + self.fileSize = fileSize; + self.entryCount = entryCount; + self.comment = comment; + self.entriesRead = 0; + self.autoClose = !!autoClose; + self.lazyEntries = !!lazyEntries; + self.decodeStrings = !!decodeStrings; + self.validateEntrySizes = !!validateEntrySizes; + self.strictFileNames = !!strictFileNames; + self.isOpen = true; + self.emittedError = false; + + if (!self.lazyEntries) self._readEntry(); +} +ZipFile.prototype.close = function() { + if (!this.isOpen) return; + this.isOpen = false; + this.reader.unref(); +}; + +function emitErrorAndAutoClose(self, err) { + if (self.autoClose) self.close(); + emitError(self, err); +} +function emitError(self, err) { + if (self.emittedError) return; + self.emittedError = true; + self.emit("error", err); +} + +ZipFile.prototype.readEntry = function() { + if (!this.lazyEntries) throw new Error("readEntry() called without lazyEntries:true"); + this._readEntry(); +}; +ZipFile.prototype._readEntry = function() { + var self = this; + if (self.entryCount === self.entriesRead) { + // done with metadata + setImmediate(function() { + if (self.autoClose) self.close(); + if (self.emittedError) return; + self.emit("end"); + }); + return; + } + if (self.emittedError) return; + var buffer = newBuffer(46); + readAndAssertNoEof(self.reader, buffer, 0, buffer.length, self.readEntryCursor, function(err) { + if (err) return emitErrorAndAutoClose(self, err); + if (self.emittedError) return; + var entry = new Entry(); + // 0 - Central directory file header signature + var signature = buffer.readUInt32LE(0); + if (signature !== 0x02014b50) return emitErrorAndAutoClose(self, new Error("invalid central directory file header signature: 0x" + signature.toString(16))); + // 4 - Version made by + entry.versionMadeBy = buffer.readUInt16LE(4); + // 6 - Version needed to extract (minimum) + entry.versionNeededToExtract = buffer.readUInt16LE(6); + // 8 - General purpose bit flag + entry.generalPurposeBitFlag = buffer.readUInt16LE(8); + // 10 - Compression method + entry.compressionMethod = buffer.readUInt16LE(10); + // 12 - File last modification time + entry.lastModFileTime = buffer.readUInt16LE(12); + // 14 - File last modification date + entry.lastModFileDate = buffer.readUInt16LE(14); + // 16 - CRC-32 + entry.crc32 = buffer.readUInt32LE(16); + // 20 - Compressed size + entry.compressedSize = buffer.readUInt32LE(20); + // 24 - Uncompressed size + entry.uncompressedSize = buffer.readUInt32LE(24); + // 28 - File name length (n) + entry.fileNameLength = buffer.readUInt16LE(28); + // 30 - Extra field length (m) + entry.extraFieldLength = buffer.readUInt16LE(30); + // 32 - File comment length (k) + entry.fileCommentLength = buffer.readUInt16LE(32); + // 34 - Disk number where file starts + // 36 - Internal file attributes + entry.internalFileAttributes = buffer.readUInt16LE(36); + // 38 - External file attributes + entry.externalFileAttributes = buffer.readUInt32LE(38); + // 42 - Relative offset of local file header + entry.relativeOffsetOfLocalHeader = buffer.readUInt32LE(42); + + if (entry.generalPurposeBitFlag & 0x40) return emitErrorAndAutoClose(self, new Error("strong encryption is not supported")); + + self.readEntryCursor += 46; + + buffer = newBuffer(entry.fileNameLength + entry.extraFieldLength + entry.fileCommentLength); + readAndAssertNoEof(self.reader, buffer, 0, buffer.length, self.readEntryCursor, function(err) { + if (err) return emitErrorAndAutoClose(self, err); + if (self.emittedError) return; + // 46 - File name + var isUtf8 = (entry.generalPurposeBitFlag & 0x800) !== 0; + entry.fileName = self.decodeStrings ? decodeBuffer(buffer, 0, entry.fileNameLength, isUtf8) + : buffer.slice(0, entry.fileNameLength); + + // 46+n - Extra field + var fileCommentStart = entry.fileNameLength + entry.extraFieldLength; + var extraFieldBuffer = buffer.slice(entry.fileNameLength, fileCommentStart); + entry.extraFields = []; + var i = 0; + while (i < extraFieldBuffer.length - 3) { + var headerId = extraFieldBuffer.readUInt16LE(i + 0); + var dataSize = extraFieldBuffer.readUInt16LE(i + 2); + var dataStart = i + 4; + var dataEnd = dataStart + dataSize; + if (dataEnd > extraFieldBuffer.length) return emitErrorAndAutoClose(self, new Error("extra field length exceeds extra field buffer size")); + var dataBuffer = newBuffer(dataSize); + extraFieldBuffer.copy(dataBuffer, 0, dataStart, dataEnd); + entry.extraFields.push({ + id: headerId, + data: dataBuffer, + }); + i = dataEnd; + } + + // 46+n+m - File comment + entry.fileComment = self.decodeStrings ? decodeBuffer(buffer, fileCommentStart, fileCommentStart + entry.fileCommentLength, isUtf8) + : buffer.slice(fileCommentStart, fileCommentStart + entry.fileCommentLength); + // compatibility hack for https://github.com/thejoshwolfe/yauzl/issues/47 + entry.comment = entry.fileComment; + + self.readEntryCursor += buffer.length; + self.entriesRead += 1; + + if (entry.uncompressedSize === 0xffffffff || + entry.compressedSize === 0xffffffff || + entry.relativeOffsetOfLocalHeader === 0xffffffff) { + // ZIP64 format + // find the Zip64 Extended Information Extra Field + var zip64EiefBuffer = null; + for (var i = 0; i < entry.extraFields.length; i++) { + var extraField = entry.extraFields[i]; + if (extraField.id === 0x0001) { + zip64EiefBuffer = extraField.data; + break; + } + } + if (zip64EiefBuffer == null) { + return emitErrorAndAutoClose(self, new Error("expected zip64 extended information extra field")); + } + var index = 0; + // 0 - Original Size 8 bytes + if (entry.uncompressedSize === 0xffffffff) { + if (index + 8 > zip64EiefBuffer.length) { + return emitErrorAndAutoClose(self, new Error("zip64 extended information extra field does not include uncompressed size")); + } + entry.uncompressedSize = readUInt64LE(zip64EiefBuffer, index); + index += 8; + } + // 8 - Compressed Size 8 bytes + if (entry.compressedSize === 0xffffffff) { + if (index + 8 > zip64EiefBuffer.length) { + return emitErrorAndAutoClose(self, new Error("zip64 extended information extra field does not include compressed size")); + } + entry.compressedSize = readUInt64LE(zip64EiefBuffer, index); + index += 8; + } + // 16 - Relative Header Offset 8 bytes + if (entry.relativeOffsetOfLocalHeader === 0xffffffff) { + if (index + 8 > zip64EiefBuffer.length) { + return emitErrorAndAutoClose(self, new Error("zip64 extended information extra field does not include relative header offset")); + } + entry.relativeOffsetOfLocalHeader = readUInt64LE(zip64EiefBuffer, index); + index += 8; + } + // 24 - Disk Start Number 4 bytes + } + + // check for Info-ZIP Unicode Path Extra Field (0x7075) + // see https://github.com/thejoshwolfe/yauzl/issues/33 + if (self.decodeStrings) { + for (var i = 0; i < entry.extraFields.length; i++) { + var extraField = entry.extraFields[i]; + if (extraField.id === 0x7075) { + if (extraField.data.length < 6) { + // too short to be meaningful + continue; + } + // Version 1 byte version of this extra field, currently 1 + if (extraField.data.readUInt8(0) !== 1) { + // > Changes may not be backward compatible so this extra + // > field should not be used if the version is not recognized. + continue; + } + // NameCRC32 4 bytes File Name Field CRC32 Checksum + var oldNameCrc32 = extraField.data.readUInt32LE(1); + if (crc32.unsigned(buffer.slice(0, entry.fileNameLength)) !== oldNameCrc32) { + // > If the CRC check fails, this UTF-8 Path Extra Field should be + // > ignored and the File Name field in the header should be used instead. + continue; + } + // UnicodeName Variable UTF-8 version of the entry File Name + entry.fileName = decodeBuffer(extraField.data, 5, extraField.data.length, true); + break; + } + } + } + + // validate file size + if (self.validateEntrySizes && entry.compressionMethod === 0) { + var expectedCompressedSize = entry.uncompressedSize; + if (entry.isEncrypted()) { + // traditional encryption prefixes the file data with a header + expectedCompressedSize += 12; + } + if (entry.compressedSize !== expectedCompressedSize) { + var msg = "compressed/uncompressed size mismatch for stored file: " + entry.compressedSize + " != " + entry.uncompressedSize; + return emitErrorAndAutoClose(self, new Error(msg)); + } + } + + if (self.decodeStrings) { + if (!self.strictFileNames) { + // allow backslash + entry.fileName = entry.fileName.replace(/\\/g, "/"); + } + var errorMessage = validateFileName(entry.fileName, self.validateFileNameOptions); + if (errorMessage != null) return emitErrorAndAutoClose(self, new Error(errorMessage)); + } + self.emit("entry", entry); + + if (!self.lazyEntries) self._readEntry(); + }); + }); +}; + +ZipFile.prototype.openReadStream = function(entry, options, callback) { + var self = this; + // parameter validation + var relativeStart = 0; + var relativeEnd = entry.compressedSize; + if (callback == null) { + callback = options; + options = {}; + } else { + // validate options that the caller has no excuse to get wrong + if (options.decrypt != null) { + if (!entry.isEncrypted()) { + throw new Error("options.decrypt can only be specified for encrypted entries"); + } + if (options.decrypt !== false) throw new Error("invalid options.decrypt value: " + options.decrypt); + if (entry.isCompressed()) { + if (options.decompress !== false) throw new Error("entry is encrypted and compressed, and options.decompress !== false"); + } + } + if (options.decompress != null) { + if (!entry.isCompressed()) { + throw new Error("options.decompress can only be specified for compressed entries"); + } + if (!(options.decompress === false || options.decompress === true)) { + throw new Error("invalid options.decompress value: " + options.decompress); + } + } + if (options.start != null || options.end != null) { + if (entry.isCompressed() && options.decompress !== false) { + throw new Error("start/end range not allowed for compressed entry without options.decompress === false"); + } + if (entry.isEncrypted() && options.decrypt !== false) { + throw new Error("start/end range not allowed for encrypted entry without options.decrypt === false"); + } + } + if (options.start != null) { + relativeStart = options.start; + if (relativeStart < 0) throw new Error("options.start < 0"); + if (relativeStart > entry.compressedSize) throw new Error("options.start > entry.compressedSize"); + } + if (options.end != null) { + relativeEnd = options.end; + if (relativeEnd < 0) throw new Error("options.end < 0"); + if (relativeEnd > entry.compressedSize) throw new Error("options.end > entry.compressedSize"); + if (relativeEnd < relativeStart) throw new Error("options.end < options.start"); + } + } + // any further errors can either be caused by the zipfile, + // or were introduced in a minor version of yauzl, + // so should be passed to the client rather than thrown. + if (!self.isOpen) return callback(new Error("closed")); + if (entry.isEncrypted()) { + if (options.decrypt !== false) return callback(new Error("entry is encrypted, and options.decrypt !== false")); + } + // make sure we don't lose the fd before we open the actual read stream + self.reader.ref(); + var buffer = newBuffer(30); + readAndAssertNoEof(self.reader, buffer, 0, buffer.length, entry.relativeOffsetOfLocalHeader, function(err) { + try { + if (err) return callback(err); + // 0 - Local file header signature = 0x04034b50 + var signature = buffer.readUInt32LE(0); + if (signature !== 0x04034b50) { + return callback(new Error("invalid local file header signature: 0x" + signature.toString(16))); + } + // all this should be redundant + // 4 - Version needed to extract (minimum) + // 6 - General purpose bit flag + // 8 - Compression method + // 10 - File last modification time + // 12 - File last modification date + // 14 - CRC-32 + // 18 - Compressed size + // 22 - Uncompressed size + // 26 - File name length (n) + var fileNameLength = buffer.readUInt16LE(26); + // 28 - Extra field length (m) + var extraFieldLength = buffer.readUInt16LE(28); + // 30 - File name + // 30+n - Extra field + var localFileHeaderEnd = entry.relativeOffsetOfLocalHeader + buffer.length + fileNameLength + extraFieldLength; + var decompress; + if (entry.compressionMethod === 0) { + // 0 - The file is stored (no compression) + decompress = false; + } else if (entry.compressionMethod === 8) { + // 8 - The file is Deflated + decompress = options.decompress != null ? options.decompress : true; + } else { + return callback(new Error("unsupported compression method: " + entry.compressionMethod)); + } + var fileDataStart = localFileHeaderEnd; + var fileDataEnd = fileDataStart + entry.compressedSize; + if (entry.compressedSize !== 0) { + // bounds check now, because the read streams will probably not complain loud enough. + // since we're dealing with an unsigned offset plus an unsigned size, + // we only have 1 thing to check for. + if (fileDataEnd > self.fileSize) { + return callback(new Error("file data overflows file bounds: " + + fileDataStart + " + " + entry.compressedSize + " > " + self.fileSize)); + } + } + var readStream = self.reader.createReadStream({ + start: fileDataStart + relativeStart, + end: fileDataStart + relativeEnd, + }); + var endpointStream = readStream; + if (decompress) { + var destroyed = false; + var inflateFilter = zlib.createInflateRaw(); + readStream.on("error", function(err) { + // setImmediate here because errors can be emitted during the first call to pipe() + setImmediate(function() { + if (!destroyed) inflateFilter.emit("error", err); + }); + }); + readStream.pipe(inflateFilter); + + if (self.validateEntrySizes) { + endpointStream = new AssertByteCountStream(entry.uncompressedSize); + inflateFilter.on("error", function(err) { + // forward zlib errors to the client-visible stream + setImmediate(function() { + if (!destroyed) endpointStream.emit("error", err); + }); + }); + inflateFilter.pipe(endpointStream); + } else { + // the zlib filter is the client-visible stream + endpointStream = inflateFilter; + } + // this is part of yauzl's API, so implement this function on the client-visible stream + endpointStream.destroy = function() { + destroyed = true; + if (inflateFilter !== endpointStream) inflateFilter.unpipe(endpointStream); + readStream.unpipe(inflateFilter); + // TODO: the inflateFilter may cause a memory leak. see Issue #27. + readStream.destroy(); + }; + } + callback(null, endpointStream); + } finally { + self.reader.unref(); + } + }); +}; + +function Entry() { +} +Entry.prototype.getLastModDate = function() { + return dosDateTimeToDate(this.lastModFileDate, this.lastModFileTime); +}; +Entry.prototype.isEncrypted = function() { + return (this.generalPurposeBitFlag & 0x1) !== 0; +}; +Entry.prototype.isCompressed = function() { + return this.compressionMethod === 8; +}; + +function dosDateTimeToDate(date, time) { + var day = date & 0x1f; // 1-31 + var month = (date >> 5 & 0xf) - 1; // 1-12, 0-11 + var year = (date >> 9 & 0x7f) + 1980; // 0-128, 1980-2108 + + var millisecond = 0; + var second = (time & 0x1f) * 2; // 0-29, 0-58 (even numbers) + var minute = time >> 5 & 0x3f; // 0-59 + var hour = time >> 11 & 0x1f; // 0-23 + + return new Date(year, month, day, hour, minute, second, millisecond); +} + +function validateFileName(fileName) { + if (fileName.indexOf("\\") !== -1) { + return "invalid characters in fileName: " + fileName; + } + if (/^[a-zA-Z]:/.test(fileName) || /^\//.test(fileName)) { + return "absolute path: " + fileName; + } + if (fileName.split("/").indexOf("..") !== -1) { + return "invalid relative path: " + fileName; + } + // all good + return null; +} + +function readAndAssertNoEof(reader, buffer, offset, length, position, callback) { + if (length === 0) { + // fs.read will throw an out-of-bounds error if you try to read 0 bytes from a 0 byte file + return setImmediate(function() { callback(null, newBuffer(0)); }); + } + reader.read(buffer, offset, length, position, function(err, bytesRead) { + if (err) return callback(err); + if (bytesRead < length) { + return callback(new Error("unexpected EOF")); + } + callback(); + }); +} + +util.inherits(AssertByteCountStream, Transform); +function AssertByteCountStream(byteCount) { + Transform.call(this); + this.actualByteCount = 0; + this.expectedByteCount = byteCount; +} +AssertByteCountStream.prototype._transform = function(chunk, encoding, cb) { + this.actualByteCount += chunk.length; + if (this.actualByteCount > this.expectedByteCount) { + var msg = "too many bytes in the stream. expected " + this.expectedByteCount + ". got at least " + this.actualByteCount; + return cb(new Error(msg)); + } + cb(null, chunk); +}; +AssertByteCountStream.prototype._flush = function(cb) { + if (this.actualByteCount < this.expectedByteCount) { + var msg = "not enough bytes in the stream. expected " + this.expectedByteCount + ". got only " + this.actualByteCount; + return cb(new Error(msg)); + } + cb(); +}; + +util.inherits(RandomAccessReader, EventEmitter); +function RandomAccessReader() { + EventEmitter.call(this); + this.refCount = 0; +} +RandomAccessReader.prototype.ref = function() { + this.refCount += 1; +}; +RandomAccessReader.prototype.unref = function() { + var self = this; + self.refCount -= 1; + + if (self.refCount > 0) return; + if (self.refCount < 0) throw new Error("invalid unref"); + + self.close(onCloseDone); + + function onCloseDone(err) { + if (err) return self.emit('error', err); + self.emit('close'); + } +}; +RandomAccessReader.prototype.createReadStream = function(options) { + var start = options.start; + var end = options.end; + if (start === end) { + var emptyStream = new PassThrough(); + setImmediate(function() { + emptyStream.end(); + }); + return emptyStream; + } + var stream = this._readStreamForRange(start, end); + + var destroyed = false; + var refUnrefFilter = new RefUnrefFilter(this); + stream.on("error", function(err) { + setImmediate(function() { + if (!destroyed) refUnrefFilter.emit("error", err); + }); + }); + refUnrefFilter.destroy = function() { + stream.unpipe(refUnrefFilter); + refUnrefFilter.unref(); + stream.destroy(); + }; + + var byteCounter = new AssertByteCountStream(end - start); + refUnrefFilter.on("error", function(err) { + setImmediate(function() { + if (!destroyed) byteCounter.emit("error", err); + }); + }); + byteCounter.destroy = function() { + destroyed = true; + refUnrefFilter.unpipe(byteCounter); + refUnrefFilter.destroy(); + }; + + return stream.pipe(refUnrefFilter).pipe(byteCounter); +}; +RandomAccessReader.prototype._readStreamForRange = function(start, end) { + throw new Error("not implemented"); +}; +RandomAccessReader.prototype.read = function(buffer, offset, length, position, callback) { + var readStream = this.createReadStream({start: position, end: position + length}); + var writeStream = new Writable(); + var written = 0; + writeStream._write = function(chunk, encoding, cb) { + chunk.copy(buffer, offset + written, 0, chunk.length); + written += chunk.length; + cb(); + }; + writeStream.on("finish", callback); + readStream.on("error", function(error) { + callback(error); + }); + readStream.pipe(writeStream); +}; +RandomAccessReader.prototype.close = function(callback) { + setImmediate(callback); +}; + +util.inherits(RefUnrefFilter, PassThrough); +function RefUnrefFilter(context) { + PassThrough.call(this); + this.context = context; + this.context.ref(); + this.unreffedYet = false; +} +RefUnrefFilter.prototype._flush = function(cb) { + this.unref(); + cb(); +}; +RefUnrefFilter.prototype.unref = function(cb) { + if (this.unreffedYet) return; + this.unreffedYet = true; + this.context.unref(); +}; + +var cp437 = '\u0000☺☻♥♦♣♠•◘○◙♂♀♪♫☼►◄↕‼¶§▬↨↑↓→←∟↔▲▼ !"#$%&\'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~⌂ÇüéâäàåçêëèïîìÄÅÉæÆôöòûùÿÖÜ¢£¥₧ƒáíóúñѪº¿⌐¬½¼¡«»░▒▓│┤╡╢╖╕╣║╗╝╜╛┐└┴┬├─┼╞╟╚╔╩╦╠═╬╧╨╤╥╙╘╒╓╫╪┘┌█▄▌▐▀αßΓπΣσµτΦΘΩδ∞φε∩≡±≥≤⌠⌡÷≈°∙·√ⁿ²■ '; +function decodeBuffer(buffer, start, end, isUtf8) { + if (isUtf8) { + return buffer.toString("utf8", start, end); + } else { + var result = ""; + for (var i = start; i < end; i++) { + result += cp437[buffer[i]]; + } + return result; + } +} + +function readUInt64LE(buffer, offset) { + // there is no native function for this, because we can't actually store 64-bit integers precisely. + // after 53 bits, JavaScript's Number type (IEEE 754 double) can't store individual integers anymore. + // but since 53 bits is a whole lot more than 32 bits, we do our best anyway. + var lower32 = buffer.readUInt32LE(offset); + var upper32 = buffer.readUInt32LE(offset + 4); + // we can't use bitshifting here, because JavaScript bitshifting only works on 32-bit integers. + return upper32 * 0x100000000 + lower32; + // as long as we're bounds checking the result of this function against the total file size, + // we'll catch any overflow errors, because we already made sure the total file size was within reason. +} + +// Node 10 deprecated new Buffer(). +var newBuffer; +if (typeof Buffer.allocUnsafe === "function") { + newBuffer = function(len) { + return Buffer.allocUnsafe(len); + }; +} else { + newBuffer = function(len) { + return new Buffer(len); + }; +} + +function defaultCallback(err) { + if (err) throw err; +} |