Initial commit

src/common/bufferSegment.js

@@ -0,0 +1,32 @@
+/**
+ * Create a buffer segment
+ * @param {Buffer} buf
+ * @param {number} [offset]
+ * @param {number} [count]
+ * @constructor
+ */
+function BufferSegment(buf, offset, count) {
+  if (!Buffer.isBuffer(buf)) throw new TypeError('buf must be a buffer');
+
+  this.buffer = buf;
+  this.offset = offset || 0;
+  this.count = count || buf.length;
+}
+
+BufferSegment.prototype.toString = function() {
+  return this.buffer.toString('utf8', this.offset, this.offset + this.count);
+};
+
+BufferSegment.prototype.toBuffer = function() {
+  if (this.offset === 0 && this.count === this.buffer.length)
+      return this.buffer;
+  return this.buffer.slice(this.offset, this.offset + this.count);
+};
+
+BufferSegment.prototype.copyTo = function(dst, offset) {
+  this.buffer.copy(dst, offset, this.offset, this.offset + this.count);
+};
+
+module.exports = function(buf, offset, count) {
+  return new BufferSegment(buf, offset, count);
+};