add vendoring with go dep

vendor/github.com/influxdata/influxdb/pkg/mmap/mmap_unix.go

@@ -0,0 +1,43 @@
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris
+
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package mmap provides a way to memory-map a file.
+package mmap
+
+import (
+	"os"
+	"syscall"
+)
+
+// Map memory-maps a file.
+func Map(path string) ([]byte, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	fi, err := f.Stat()
+	if err != nil {
+		return nil, err
+	} else if fi.Size() == 0 {
+		return nil, nil
+	}
+
+	data, err := syscall.Mmap(int(f.Fd()), 0, int(fi.Size()), syscall.PROT_READ, syscall.MAP_SHARED)
+	if err != nil {
+		return nil, err
+	}
+	return data, nil
+}
+
+// Unmap closes the memory-map.
+func Unmap(data []byte) error {
+	if data == nil {
+		return nil
+	}
+	return syscall.Munmap(data)
+}