1 files changed, 101 insertions, 0 deletions
diff --git a/node_modules/compress-commons/lib/archivers/zip/general-purpose-bit.js b/node_modules/compress-commons/lib/archivers/zip/general-purpose-bit.js
new file mode 100644
index 000000000..08b62b896
--- /dev/null
+++ b/node_modules/compress-commons/lib/archivers/zip/general-purpose-bit.js
@@ -0,0 +1,101 @@
+/**
+ * node-compress-commons
+ *
+ * Copyright (c) 2014 Chris Talkington, contributors.
+ * Licensed under the MIT license.
+ * https://github.com/archiverjs/node-compress-commons/blob/master/LICENSE-MIT
+ */
+var zipUtil = require('./util');
+
+var DATA_DESCRIPTOR_FLAG = 1 << 3;
+var ENCRYPTION_FLAG = 1 << 0;
+var NUMBER_OF_SHANNON_FANO_TREES_FLAG = 1 << 2;
+var SLIDING_DICTIONARY_SIZE_FLAG = 1 << 1;
+var STRONG_ENCRYPTION_FLAG = 1 << 6;
+var UFT8_NAMES_FLAG = 1 << 11;
+
+var GeneralPurposeBit = module.exports = function() {
+  if (!(this instanceof GeneralPurposeBit)) {
+    return new GeneralPurposeBit();
+  }
+
+  this.descriptor = false;
+  this.encryption = false;
+  this.utf8 = false;
+  this.numberOfShannonFanoTrees = 0;
+  this.strongEncryption = false;
+  this.slidingDictionarySize = 0;
+
+  return this;
+};
+
+GeneralPurposeBit.prototype.encode = function() {
+  return zipUtil.getShortBytes(
+    (this.descriptor ? DATA_DESCRIPTOR_FLAG : 0) |
+    (this.utf8 ? UFT8_NAMES_FLAG : 0) |
+    (this.encryption ? ENCRYPTION_FLAG : 0) |
+    (this.strongEncryption ? STRONG_ENCRYPTION_FLAG : 0)
+  );
+};
+
+GeneralPurposeBit.prototype.parse = function(buf, offset) {
+  var flag = zipUtil.getShortBytesValue(buf, offset);
+  var gbp = new GeneralPurposeBit();
+
+  gbp.useDataDescriptor((flag & DATA_DESCRIPTOR_FLAG) !== 0);
+  gbp.useUTF8ForNames((flag & UFT8_NAMES_FLAG) !== 0);
+  gbp.useStrongEncryption((flag & STRONG_ENCRYPTION_FLAG) !== 0);
+  gbp.useEncryption((flag & ENCRYPTION_FLAG) !== 0);
+  gbp.setSlidingDictionarySize((flag & SLIDING_DICTIONARY_SIZE_FLAG) !== 0 ? 8192 : 4096);
+  gbp.setNumberOfShannonFanoTrees((flag & NUMBER_OF_SHANNON_FANO_TREES_FLAG) !== 0 ? 3 : 2);
+
+  return gbp;
+};
+
+GeneralPurposeBit.prototype.setNumberOfShannonFanoTrees = function(n) {
+  this.numberOfShannonFanoTrees = n;
+};
+
+GeneralPurposeBit.prototype.getNumberOfShannonFanoTrees = function() {
+  return this.numberOfShannonFanoTrees;
+};
+
+GeneralPurposeBit.prototype.setSlidingDictionarySize = function(n) {
+  this.slidingDictionarySize = n;
+};
+
+GeneralPurposeBit.prototype.getSlidingDictionarySize = function() {
+  return this.slidingDictionarySize;
+};
+
+GeneralPurposeBit.prototype.useDataDescriptor = function(b) {
+  this.descriptor = b;
+};
+
+GeneralPurposeBit.prototype.usesDataDescriptor = function() {
+  return this.descriptor;
+};
+
+GeneralPurposeBit.prototype.useEncryption = function(b) {
+  this.encryption = b;
+};
+
+GeneralPurposeBit.prototype.usesEncryption = function() {
+  return this.encryption;
+};
+
+GeneralPurposeBit.prototype.useStrongEncryption = function(b) {
+  this.strongEncryption = b;
+};
+
+GeneralPurposeBit.prototype.usesStrongEncryption = function() {
+  return this.strongEncryption;
+};
+
+GeneralPurposeBit.prototype.useUTF8ForNames = function(b) {
+  this.utf8 = b;
+};
+
+GeneralPurposeBit.prototype.usesUTF8ForNames = function() {
+  return this.utf8;
+};
+\ No newline at end of file