@@ -36,10 +36,14 @@ packages=(

 	graph

 	image

 	integration-cli

+	pkg/broadcastwriter

 	pkg/chrootarchive

 	pkg/directory

 	pkg/fileutils

+	pkg/graphdb

 	pkg/homedir

+	pkg/httputils

+	pkg/ioutils

 	pkg/listenbuffer

 	pkg/mflag

 	pkg/mflag/example

@@ -44,6 +44,7 @@ func (w *BroadcastWriter) Clean() error {

 	return nil

 }

+// New creates a new BroadcastWriter.

 func New() *BroadcastWriter {

 	return &BroadcastWriter{

 		writers: make(map[io.WriteCloser]struct{}),

@@ -2,4 +2,6 @@

 package graphdb

-import _ "code.google.com/p/gosqlite/sqlite3" // registers sqlite

+import (

+	_ "code.google.com/p/gosqlite/sqlite3" // registers sqlite

+)

@@ -2,4 +2,6 @@

 package graphdb

-import _ "github.com/mattn/go-sqlite3" // registers sqlite

+import (

+	_ "github.com/mattn/go-sqlite3" // registers sqlite

+)

@@ -2,6 +2,7 @@

 package graphdb

+// NewSqliteConn return a new sqlite connection.

 func NewSqliteConn(root string) (*Database, error) {

 	panic("Not implemented")

 }

@@ -29,28 +29,28 @@ const (

     `

 )

-// Entity with a unique id

+// Entity with a unique id.

 type Entity struct {

 	id string

 }

-// An Edge connects two entities together

+// An Edge connects two entities together.

 type Edge struct {

 	EntityID string

 	Name     string

 	ParentID string

 }

-// Entities stores the list of entities

+// Entities stores the list of entities.

 type Entities map[string]*Entity

-// Edges stores the relationships between entities

+// Edges stores the relationships between entities.

 type Edges []*Edge

-// WalkFunc is a function invoked to process an individual entity

+// WalkFunc is a function invoked to process an individual entity.

 type WalkFunc func(fullPath string, entity *Entity) error

-// Database is a graph database for storing entities and their relationships

+// Database is a graph database for storing entities and their relationships.

 type Database struct {

 	conn *sql.DB

 	mux  sync.RWMutex

@@ -80,7 +80,7 @@ func IsNonUniqueNameError(err error) bool {

 	return false

 }

-// NewDatabase creates a new graph database initialized with a root entity

+// NewDatabase creates a new graph database initialized with a root entity.

 func NewDatabase(conn *sql.DB) (*Database, error) {

 	if conn == nil {

 		return nil, fmt.Errorf("Database connection cannot be nil")

@@ -130,12 +130,12 @@ func NewDatabase(conn *sql.DB) (*Database, error) {

 	return db, nil

 }

-// Close the underlying connection to the database

+// Close the underlying connection to the database.

 func (db *Database) Close() error {

 	return db.conn.Close()

 }

-// Set the entity id for a given path

+// Set the entity id for a given path.

 func (db *Database) Set(fullPath, id string) (*Entity, error) {

 	db.mux.Lock()

 	defer db.mux.Unlock()

@@ -171,7 +171,7 @@ func (db *Database) Set(fullPath, id string) (*Entity, error) {

 	return e, nil

 }

-// Exists returns true if a name already exists in the database

+// Exists returns true if a name already exists in the database.

 func (db *Database) Exists(name string) bool {

 	db.mux.RLock()

 	defer db.mux.RUnlock()

@@ -198,14 +198,14 @@ func (db *Database) setEdge(parentPath, name string, e *Entity, tx *sql.Tx) erro

 	return nil

 }

-// RootEntity returns the root "/" entity for the database

+// RootEntity returns the root "/" entity for the database.

 func (db *Database) RootEntity() *Entity {

 	return &Entity{

 		id: "0",

 	}

 }

-// Get returns the entity for a given path

+// Get returns the entity for a given path.

 func (db *Database) Get(name string) *Entity {

 	db.mux.RLock()

 	defer db.mux.RUnlock()

@@ -242,8 +242,8 @@ func (db *Database) get(name string) (*Entity, error) {

 }

-// List all entities by from the name

-// The key will be the full path of the entity

+// List all entities by from the name.

+// The key will be the full path of the entity.

 func (db *Database) List(name string, depth int) Entities {

 	db.mux.RLock()

 	defer db.mux.RUnlock()

@@ -282,7 +282,7 @@ func (db *Database) Walk(name string, walkFunc WalkFunc, depth int) error {

 	return nil

 }

-// Children returns the children of the specified entity

+// Children returns the children of the specified entity.

 func (db *Database) Children(name string, depth int) ([]WalkMeta, error) {

 	db.mux.RLock()

 	defer db.mux.RUnlock()

@@ -295,7 +295,7 @@ func (db *Database) Children(name string, depth int) ([]WalkMeta, error) {

 	return db.children(e, name, depth, nil)

 }

-// Parents returns the parents of a specified entity

+// Parents returns the parents of a specified entity.

 func (db *Database) Parents(name string) ([]string, error) {

 	db.mux.RLock()

 	defer db.mux.RUnlock()

@@ -307,7 +307,7 @@ func (db *Database) Parents(name string) ([]string, error) {

 	return db.parents(e)

 }

-// Refs returns the refrence count for a specified id

+// Refs returns the refrence count for a specified id.

 func (db *Database) Refs(id string) int {

 	db.mux.RLock()

 	defer db.mux.RUnlock()

@@ -319,7 +319,7 @@ func (db *Database) Refs(id string) int {

 	return count

 }

-// RefPaths returns all the id's path references

+// RefPaths returns all the id's path references.

 func (db *Database) RefPaths(id string) Edges {

 	db.mux.RLock()

 	defer db.mux.RUnlock()

@@ -347,7 +347,7 @@ func (db *Database) RefPaths(id string) Edges {

 	return refs

 }

-// Delete the reference to an entity at a given path

+// Delete the reference to an entity at a given path.

 func (db *Database) Delete(name string) error {

 	db.mux.Lock()

 	defer db.mux.Unlock()

@@ -446,6 +446,7 @@ func (db *Database) Rename(currentName, newName string) error {

 	return nil

 }

+// WalkMeta stores the walk metadata.

 type WalkMeta struct {

 	Parent   *Entity

 	Entity   *Entity

@@ -522,7 +523,7 @@ func (db *Database) parents(e *Entity) (parents []string, err error) {

 	return parents, nil

 }

-// Return the entity based on the parent path and name

+// Return the entity based on the parent path and name.

 func (db *Database) child(parent *Entity, name string) *Entity {

 	var id string

 	if err := db.conn.QueryRow("SELECT entity_id FROM edge WHERE parent_id = ? AND name = ?;", parent.id, name).Scan(&id); err != nil {

@@ -531,12 +532,12 @@ func (db *Database) child(parent *Entity, name string) *Entity {

 	return &Entity{id}

 }

-// ID returns the id used to reference this entity

+// ID returns the id used to reference this entity.

 func (e *Entity) ID() string {

 	return e.id

 }

-// Paths returns the paths sorted by depth

+// Paths returns the paths sorted by depth.

 func (e Entities) Paths() []string {

 	out := make([]string, len(e))

 	var i int

@@ -10,7 +10,7 @@ import (

 	"github.com/docker/docker/pkg/jsonmessage"

 )

-// Download requests a given URL and returns an io.Reader

+// Download requests a given URL and returns an io.Reader.

 func Download(url string) (resp *http.Response, err error) {

 	if resp, err = http.Get(url); err != nil {

 		return nil, err

@@ -21,7 +21,7 @@ func Download(url string) (resp *http.Response, err error) {

 	return resp, nil

 }

-// NewHTTPRequestError returns a JSON response error

+// NewHTTPRequestError returns a JSON response error.

 func NewHTTPRequestError(msg string, res *http.Response) error {

 	return &jsonmessage.JSONError{

 		Message: msg,

@@ -29,14 +29,15 @@ func NewHTTPRequestError(msg string, res *http.Response) error {

 	}

 }

+// ServerHeader contains the server information.

 type ServerHeader struct {

 	App string // docker

 	Ver string // 1.8.0-dev

 	OS  string // windows or linux

 }

-// parseServerHeader extracts pieces from am HTTP server header

-// which is in the format "docker/version (os)" eg docker/1.8.0-dev (windows)

+// ParseServerHeader extracts pieces from an HTTP server header

+// which is in the format "docker/version (os)" eg docker/1.8.0-dev (windows).

 func ParseServerHeader(hdr string) (*ServerHeader, error) {

 	re := regexp.MustCompile(`.*\((.+)\).*$`)

 	r := &ServerHeader{}

@@ -5,6 +5,7 @@ import (

 	"net/http"

 )

+// MimeTypes stores the MIME content type.

 var MimeTypes = struct {

 	TextPlain   string

 	Tar         string

@@ -53,7 +53,7 @@ func (r *multiReadSeeker) Seek(offset int64, whence int) (int64, error) {

 			}

 			if rdrOffset == s && i != len(r.readers)-1 {

-				idx += 1

+				idx++

 				rdrOffset = 0

 			}

 			r.pos = &pos{idx, rdrOffset}

@@ -23,6 +23,7 @@ func (r *readCloserWrapper) Close() error {

 	return r.closer()

 }

+// NewReadCloserWrapper returns a new io.ReadCloser.

 func NewReadCloserWrapper(r io.Reader, closer func() error) io.ReadCloser {

 	return &readCloserWrapper{

 		Reader: r,

@@ -43,6 +44,7 @@ func (r *readerErrWrapper) Read(p []byte) (int, error) {

 	return n, err

 }

+// NewReaderErrWrapper returns a new io.Reader.

 func NewReaderErrWrapper(r io.Reader, closer func()) io.Reader {

 	return &readerErrWrapper{

 		reader: r,

@@ -68,7 +70,8 @@ type bufReader struct {

 	maxReadDataReset     int64

 }

-func NewBufReader(r io.Reader) *bufReader {

+// NewBufReader returns a new bufReader.

+func NewBufReader(r io.Reader) io.ReadCloser {

 	timeout := rand.New(rndSrc).Intn(120) + 180

 	reader := &bufReader{

@@ -86,7 +89,8 @@ func NewBufReader(r io.Reader) *bufReader {

 	return reader

 }

-func NewBufReaderWithDrainbufAndBuffer(r io.Reader, drainBuffer []byte, buffer *bytes.Buffer) *bufReader {

+// NewBufReaderWithDrainbufAndBuffer returns a BufReader with drainBuffer and buffer.

+func NewBufReaderWithDrainbufAndBuffer(r io.Reader, drainBuffer []byte, buffer *bytes.Buffer) io.ReadCloser {

 	reader := &bufReader{

 		buf:      buffer,

 		drainBuf: drainBuffer,

@@ -210,6 +214,7 @@ func (r *bufReader) Read(p []byte) (n int, err error) {

 	}

 }

+// Close closes the bufReader

 func (r *bufReader) Close() error {

 	closer, ok := r.reader.(io.ReadCloser)

 	if !ok {

@@ -218,6 +223,7 @@ func (r *bufReader) Close() error {

 	return closer.Close()

 }

+// HashData returns the sha256 sum of src.

 func HashData(src io.Reader) (string, error) {

 	h := sha256.New()

 	if _, err := io.Copy(h, src); err != nil {

@@ -226,6 +232,8 @@ func HashData(src io.Reader) (string, error) {

 	return "sha256:" + hex.EncodeToString(h.Sum(nil)), nil

 }

+// OnEOFReader wraps a io.ReadCloser and a function

+// the fuction will run at the end of file or close the file.

 type OnEOFReader struct {

 	Rc io.ReadCloser

 	Fn func()

@@ -239,6 +247,7 @@ func (r *OnEOFReader) Read(p []byte) (n int, err error) {

 	return

 }

+// Close closes the file and run the function.

 func (r *OnEOFReader) Close() error {

 	err := r.Rc.Close()

 	r.runFunc()

@@ -6,6 +6,7 @@ import (

 	"sync"

 )

+// WriteFlusher wraps the Write and Flush operation.

 type WriteFlusher struct {

 	sync.Mutex

 	w       io.Writer

@@ -30,12 +31,15 @@ func (wf *WriteFlusher) Flush() {

 	wf.flusher.Flush()

 }

+// Flushed returns the state of flushed.

+// If it's flushed, return true, or else it return false.

 func (wf *WriteFlusher) Flushed() bool {

 	wf.Lock()

 	defer wf.Unlock()

 	return wf.flushed

 }

+// NewWriteFlusher returns a new WriteFlusher.

 func NewWriteFlusher(w io.Writer) *WriteFlusher {

 	var flusher http.Flusher

 	if f, ok := w.(http.Flusher); ok {

@@ -2,6 +2,7 @@ package ioutils

 import "io"

+// NopWriter represents a type which write operation is nop.

 type NopWriter struct{}

 func (*NopWriter) Write(buf []byte) (int, error) {

@@ -14,12 +15,15 @@ type nopWriteCloser struct {

 func (w *nopWriteCloser) Close() error { return nil }

+// NopWriteCloser returns a nopWriteCloser.

 func NopWriteCloser(w io.Writer) io.WriteCloser {

 	return &nopWriteCloser{w}

 }

+// NopFlusher represents a type which flush opetatin is nop.

 type NopFlusher struct{}

+// Flush is a nop operation.

 func (f *NopFlusher) Flush() {}

 type writeCloserWrapper struct {

@@ -31,6 +35,7 @@ func (r *writeCloserWrapper) Close() error {

 	return r.closer()

 }

+// NewWriteCloserWrapper returns a new io.WriteCloser.

 func NewWriteCloserWrapper(r io.Writer, closer func() error) io.WriteCloser {

 	return &writeCloserWrapper{

 		Writer: r,

@@ -38,7 +43,7 @@ func NewWriteCloserWrapper(r io.Writer, closer func() error) io.WriteCloser {

 	}

 }

-// Wrap a concrete io.Writer and hold a count of the number

+// WriteCounter wraps a concrete io.Writer and hold a count of the number

 // of bytes written to the writer during a "session".

 // This can be convenient when write return is masked

 // (e.g., json.Encoder.Encode())

@@ -47,6 +52,7 @@ type WriteCounter struct {

 	Writer io.Writer

 }

+// NewWriteCounter returns a new WriteCounter.

 func NewWriteCounter(w io.Writer) *WriteCounter {

 	return &WriteCounter{

 		Writer: w,