diff options
Diffstat (limited to 'node_modules/crc32-stream/lib/deflate-crc32-stream.js')
-rw-r--r-- | node_modules/crc32-stream/lib/deflate-crc32-stream.js | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/node_modules/crc32-stream/lib/deflate-crc32-stream.js b/node_modules/crc32-stream/lib/deflate-crc32-stream.js new file mode 100644 index 000000000..944eb0d0a --- /dev/null +++ b/node_modules/crc32-stream/lib/deflate-crc32-stream.js @@ -0,0 +1,67 @@ +/**
+ * node-crc32-stream
+ *
+ * Copyright (c) 2014 Chris Talkington, contributors.
+ * Licensed under the MIT license.
+ * https://github.com/archiverjs/node-crc32-stream/blob/master/LICENSE-MIT
+ */
+var zlib = require('zlib');
+var inherits = require('util').inherits;
+
+var crc32 = require('buffer-crc32');
+
+var DeflateCRC32Stream = module.exports = function (options) {
+ zlib.DeflateRaw.call(this, options);
+
+ this.checksum = new Buffer(4);
+ this.checksum.writeInt32BE(0, 0);
+
+ this.rawSize = 0;
+ this.compressedSize = 0;
+
+ // BC v0.8
+ if (typeof zlib.DeflateRaw.prototype.push !== 'function') {
+ this.on('data', function(chunk) {
+ if (chunk) {
+ this.compressedSize += chunk.length;
+ }
+ });
+ }
+};
+
+inherits(DeflateCRC32Stream, zlib.DeflateRaw);
+
+DeflateCRC32Stream.prototype.push = function(chunk, encoding) {
+ if (chunk) {
+ this.compressedSize += chunk.length;
+ }
+
+ return zlib.DeflateRaw.prototype.push.call(this, chunk, encoding);
+};
+
+DeflateCRC32Stream.prototype.write = function(chunk, enc, cb) {
+ if (chunk) {
+ this.checksum = crc32(chunk, this.checksum);
+ this.rawSize += chunk.length;
+ }
+
+ return zlib.DeflateRaw.prototype.write.call(this, chunk, enc, cb);
+};
+
+DeflateCRC32Stream.prototype.digest = function() {
+ return crc32.unsigned(0, this.checksum);
+};
+
+DeflateCRC32Stream.prototype.hex = function() {
+ return this.digest().toString(16).toUpperCase();
+};
+
+DeflateCRC32Stream.prototype.size = function(compressed) {
+ compressed = compressed || false;
+
+ if (compressed) {
+ return this.compressedSize;
+ } else {
+ return this.rawSize;
+ }
+};
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