1. adding statistics reporting

2. refactor version to util package

go/stats/disk.go

@@ -0,0 +1,26 @@
+// +build !windows
+
+package stats
+
+import (
+	"syscall"
+)
+
+type DiskStatus struct {
+	All  uint64 `json:"all"`
+	Used uint64 `json:"used"`
+	Free uint64 `json:"free"`
+}
+
+func DiskUsage(path string) (disk *DiskStatus) {
+	disk = &DiskStatus{}
+	fs := syscall.Statfs_t{}
+	err := syscall.Statfs(path, &fs)
+	if err != nil {
+		return
+	}
+	disk.All = fs.Blocks * uint64(fs.Bsize)
+	disk.Free = fs.Bfree * uint64(fs.Bsize)
+	disk.Used = disk.All - disk.Free
+	return
+}