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"use strict";
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.isBinaryFileSync = exports.isBinaryFile = void 0;
const fs = require("fs");
const util_1 = require("util");
const statAsync = util_1.promisify(fs.stat);
const openAsync = util_1.promisify(fs.open);
const closeAsync = util_1.promisify(fs.close);
const MAX_BYTES = 512;
// A very basic non-exception raising reader. Read bytes and
// at the end use hasError() to check whether this worked.
class Reader {
constructor(fileBuffer, size) {
this.fileBuffer = fileBuffer;
this.size = size;
this.offset = 0;
this.error = false;
}
hasError() {
return this.error;
}
nextByte() {
if (this.offset === this.size || this.hasError()) {
this.error = true;
return 0xff;
}
return this.fileBuffer[this.offset++];
}
next(len) {
const n = new Array();
for (let i = 0; i < len; i++) {
n[i] = this.nextByte();
}
return n;
}
}
// Read a Google Protobuf var(iable)int from the buffer.
function readProtoVarInt(reader) {
let idx = 0;
let varInt = 0;
while (!reader.hasError()) {
const b = reader.nextByte();
varInt = varInt | ((b & 0x7f) << (7 * idx));
if ((b & 0x80) === 0) {
break;
}
idx++;
}
return varInt;
}
// Attempt to taste a full Google Protobuf message.
function readProtoMessage(reader) {
const varInt = readProtoVarInt(reader);
const wireType = varInt & 0x7;
switch (wireType) {
case 0:
readProtoVarInt(reader);
return true;
case 1:
reader.next(8);
return true;
case 2:
const len = readProtoVarInt(reader);
reader.next(len);
return true;
case 5:
reader.next(4);
return true;
}
return false;
}
// Check whether this seems to be a valid protobuf file.
function isBinaryProto(fileBuffer, totalBytes) {
const reader = new Reader(fileBuffer, totalBytes);
let numMessages = 0;
while (true) {
// Definitely not a valid protobuf
if (!readProtoMessage(reader) && !reader.hasError()) {
return false;
}
// Short read?
if (reader.hasError()) {
break;
}
numMessages++;
}
return numMessages > 0;
}
function isBinaryFile(file, size) {
return __awaiter(this, void 0, void 0, function* () {
if (isString(file)) {
const stat = yield statAsync(file);
isStatFile(stat);
const fileDescriptor = yield openAsync(file, 'r');
const allocBuffer = Buffer.alloc(MAX_BYTES);
// Read the file with no encoding for raw buffer access.
// NB: something is severely wrong with promisify, had to construct my own Promise
return new Promise((fulfill, reject) => {
fs.read(fileDescriptor, allocBuffer, 0, MAX_BYTES, 0, (err, bytesRead, _) => {
closeAsync(fileDescriptor);
if (err) {
reject(err);
}
else {
fulfill(isBinaryCheck(allocBuffer, bytesRead));
}
});
});
}
else {
if (size === undefined) {
size = file.length;
}
return isBinaryCheck(file, size);
}
});
}
exports.isBinaryFile = isBinaryFile;
function isBinaryFileSync(file, size) {
if (isString(file)) {
const stat = fs.statSync(file);
isStatFile(stat);
const fileDescriptor = fs.openSync(file, 'r');
const allocBuffer = Buffer.alloc(MAX_BYTES);
const bytesRead = fs.readSync(fileDescriptor, allocBuffer, 0, MAX_BYTES, 0);
fs.closeSync(fileDescriptor);
return isBinaryCheck(allocBuffer, bytesRead);
}
else {
if (size === undefined) {
size = file.length;
}
return isBinaryCheck(file, size);
}
}
exports.isBinaryFileSync = isBinaryFileSync;
function isBinaryCheck(fileBuffer, bytesRead) {
// empty file. no clue what it is.
if (bytesRead === 0) {
return false;
}
let suspiciousBytes = 0;
const totalBytes = Math.min(bytesRead, MAX_BYTES);
// UTF-8 BOM
if (bytesRead >= 3 && fileBuffer[0] === 0xef && fileBuffer[1] === 0xbb && fileBuffer[2] === 0xbf) {
return false;
}
// UTF-32 BOM
if (bytesRead >= 4 &&
fileBuffer[0] === 0x00 &&
fileBuffer[1] === 0x00 &&
fileBuffer[2] === 0xfe &&
fileBuffer[3] === 0xff) {
return false;
}
// UTF-32 LE BOM
if (bytesRead >= 4 &&
fileBuffer[0] === 0xff &&
fileBuffer[1] === 0xfe &&
fileBuffer[2] === 0x00 &&
fileBuffer[3] === 0x00) {
return false;
}
// GB BOM
if (bytesRead >= 4 &&
fileBuffer[0] === 0x84 &&
fileBuffer[1] === 0x31 &&
fileBuffer[2] === 0x95 &&
fileBuffer[3] === 0x33) {
return false;
}
if (totalBytes >= 5 && fileBuffer.slice(0, 5).toString() === '%PDF-') {
/* PDF. This is binary. */
return true;
}
// UTF-16 BE BOM
if (bytesRead >= 2 && fileBuffer[0] === 0xfe && fileBuffer[1] === 0xff) {
return false;
}
// UTF-16 LE BOM
if (bytesRead >= 2 && fileBuffer[0] === 0xff && fileBuffer[1] === 0xfe) {
return false;
}
for (let i = 0; i < totalBytes; i++) {
if (fileBuffer[i] === 0) {
// NULL byte--it's binary!
return true;
}
else if ((fileBuffer[i] < 7 || fileBuffer[i] > 14) && (fileBuffer[i] < 32 || fileBuffer[i] > 127)) {
// UTF-8 detection
if (fileBuffer[i] > 193 && fileBuffer[i] < 224 && i + 1 < totalBytes) {
i++;
if (fileBuffer[i] > 127 && fileBuffer[i] < 192) {
continue;
}
}
else if (fileBuffer[i] > 223 && fileBuffer[i] < 240 && i + 2 < totalBytes) {
i++;
if (fileBuffer[i] > 127 && fileBuffer[i] < 192 && fileBuffer[i + 1] > 127 && fileBuffer[i + 1] < 192) {
i++;
continue;
}
}
suspiciousBytes++;
// Read at least 32 fileBuffer before making a decision
if (i >= 32 && (suspiciousBytes * 100) / totalBytes > 10) {
return true;
}
}
}
if ((suspiciousBytes * 100) / totalBytes > 10) {
return true;
}
if (suspiciousBytes > 1 && isBinaryProto(fileBuffer, totalBytes)) {
return true;
}
return false;
}
function isString(x) {
return typeof x === 'string';
}
function isStatFile(stat) {
if (!stat.isFile()) {
throw new Error(`Path provided was not a file!`);
}
}
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