1 files changed, 21 insertions, 1 deletions
diff --git a/libgo/go/os/user/lookup.go b/libgo/go/os/user/lookup.go
index 3b4421badd5..2243a25788a 100644
--- a/libgo/go/os/user/lookup.go
+++ b/libgo/go/os/user/lookup.go
@@ -4,20 +4,40 @@
 
 package user
 
+import "sync"
+
 // Current returns the current user.
 func Current() (*User, error) {
-	return current()
+	cache.Do(func() { cache.u, cache.err = current() })
+	if cache.err != nil {
+		return nil, cache.err
+	}
+	u := *cache.u // copy
+	return &u, nil
+}
+
+// cache of the current user
+var cache struct {
+	sync.Once
+	u   *User
+	err error
 }
 
 // Lookup looks up a user by username. If the user cannot be found, the
 // returned error is of type UnknownUserError.
 func Lookup(username string) (*User, error) {
+	if u, err := Current(); err == nil && u.Username == username {
+		return u, err
+	}
 	return lookupUser(username)
 }
 
 // LookupId looks up a user by userid. If the user cannot be found, the
 // returned error is of type UnknownUserIdError.
 func LookupId(uid string) (*User, error) {
+	if u, err := Current(); err == nil && u.Uid == uid {
+		return u, err
+	}
 	return lookupUserId(uid)
 }