Better error handling, new commands.

The code is no safer.
Added Stor(), Rename(), NoOp()
Improved Retr()
Added client tests (requires a ftp server on localhost)
This commit is contained in:
jlaffaye
2011-09-05 23:36:14 +02:00
parent faca79d4ea
commit a87255661d
4 changed files with 204 additions and 44 deletions

182
ftp.go
View File

@@ -2,6 +2,7 @@ package ftp
import (
"bufio"
"io"
"net"
"net/textproto"
"os"
@@ -10,8 +11,10 @@ import (
"strings"
)
type EntryType int
const (
EntryTypeFile = iota
EntryTypeFile EntryType = iota
EntryTypeFolder
EntryTypeLink
)
@@ -21,17 +24,17 @@ type ServerConn struct {
host string
}
type Response struct {
conn net.Conn
c *ServerConn
}
type Entry struct {
Name string
EntryType int
Type EntryType
Size uint64
}
type response struct {
conn net.Conn
c *ServerConn
}
// Connect to a ftp server and returns a ServerConn handler.
func Connect(host, user, password string) (*ServerConn, os.Error) {
conn, err := textproto.Dial("tcp", host)
@@ -39,26 +42,26 @@ func Connect(host, user, password string) (*ServerConn, os.Error) {
return nil, err
}
a := strings.Split(host, ":", 2)
a := strings.SplitN(host, ":", 2)
c := &ServerConn{conn, a[0]}
_, _, err = c.conn.ReadCodeLine(StatusReady)
if err != nil {
c.Close()
c.Quit()
return nil, err
}
c.conn.Cmd("USER %s", user)
_, _, err = c.conn.ReadCodeLine(StatusUserOK)
if err != nil {
c.Close()
c.Quit()
return nil, err
}
c.conn.Cmd("PASS %s", password)
_, _, err = c.conn.ReadCodeLine(StatusLoggedIn)
if err != nil {
c.Close()
c.Quit()
return nil, err
}
@@ -88,10 +91,10 @@ func (c *ServerConn) epsv() (port int, err os.Error) {
}
// Open a new data connection using extended passive mode
func (c *ServerConn) openDataConnection() (r *Response, err os.Error) {
func (c *ServerConn) openDataConnection() (net.Conn, os.Error) {
port, err := c.epsv()
if err != nil {
return
return nil, err
}
// Build the new net address string
@@ -99,11 +102,25 @@ func (c *ServerConn) openDataConnection() (r *Response, err os.Error) {
conn, err := net.Dial("tcp", addr)
if err != nil {
return
return nil, err
}
r = &Response{conn, c}
return
return conn, nil
}
// Helper function to check if the last command succeeded and if it will
// send the data to the data connection.
// This is needed because some servers return StatusAboutToSend (150)
// and some StatusAlreadyOpen (125)
func (c *ServerConn) checkDataConn() os.Error {
code, msg, err := c.conn.ReadCodeLine(-1)
if err != nil {
return err
}
if code != StatusAlreadyOpen && code != StatusAboutToSend {
return os.NewError(fmt.Sprintf("%d %s", code, msg))
}
return nil
}
func parseListLine(line string) (*Entry, os.Error) {
@@ -114,14 +131,14 @@ func parseListLine(line string) (*Entry, os.Error) {
e := &Entry{}
switch fields[0][0] {
case '-':
e.EntryType = EntryTypeFile
case 'd':
e.EntryType = EntryTypeFolder
case 'l':
e.EntryType = EntryTypeLink
default:
return nil, os.NewError("Unknown entry type")
case '-':
e.Type = EntryTypeFile
case 'd':
e.Type = EntryTypeFolder
case 'l':
e.Type = EntryTypeLink
default:
return nil, os.NewError("Unknown entry type")
}
e.Name = strings.Join(fields[8:], " ")
@@ -129,14 +146,20 @@ func parseListLine(line string) (*Entry, os.Error) {
}
func (c *ServerConn) List(path string) (entries []*Entry, err os.Error) {
r, err := c.openDataConnection()
conn, err := c.openDataConnection()
if err != nil {
return
}
r := &response{conn, c}
defer r.Close()
c.conn.Cmd("LIST %s", path)
_, _, err = c.conn.ReadCodeLine(StatusAboutToSend)
_, err = c.conn.Cmd("LIST %s", path)
if err != nil {
return
}
err = c.checkDataConn()
if err != nil {
return
}
@@ -158,28 +181,109 @@ func (c *ServerConn) List(path string) (entries []*Entry, err os.Error) {
}
func (c *ServerConn) ChangeDir(path string) (err os.Error) {
c.conn.Cmd("CWD %s", path);
_, _, err = c.conn.ReadCodeLine(StatusRequestedFileActionOK)
_, err = c.conn.Cmd("CWD %s", path)
if err == nil {
_, _, err = c.conn.ReadCodeLine(StatusRequestedFileActionOK)
}
return
}
func (c *ServerConn) Get(path string) (r *Response, err os.Error) {
r, err = c.openDataConnection()
// Retrieves a remote file
func (c *ServerConn) Retr(path string) (io.ReadCloser, os.Error) {
conn, err := c.openDataConnection()
if err != nil {
return
return nil, err
}
c.conn.Cmd("RETR %s", path)
_, _, err = c.conn.ReadCodeLine(StatusAboutToSend)
return
_, err = c.conn.Cmd("RETR %s", path)
if err != nil {
conn.Close()
return nil, err
}
err = c.checkDataConn()
if err != nil {
conn.Close()
return nil, err
}
r := &response{conn, c}
return r, nil
}
func (c *ServerConn) Close() {
func (c *ServerConn) Stor(name string, r io.Reader) os.Error {
conn, err := c.openDataConnection()
if err != nil {
return err
}
_, err = c.conn.Cmd("STOR %s", name)
if err != nil {
conn.Close()
return err
}
err = c.checkDataConn()
if err != nil {
conn.Close()
return err
}
_, err = io.Copy(conn, r)
conn.Close()
if err != nil {
return err
}
_, _, err = c.conn.ReadCodeLine(StatusClosingDataConnection)
return err
}
func (c *ServerConn) Rename(from, to string) os.Error {
_, err := c.conn.Cmd("RNFR %s", from)
if err != nil {
return err
}
_, _, err = c.conn.ReadCodeLine(StatusRequestFilePending)
if err != nil {
return err
}
_, err = c.conn.Cmd("RNTO %s", to)
if err != nil {
return err
}
_, _, err = c.conn.ReadCodeLine(StatusRequestedFileActionOK)
return err
}
func (c *ServerConn) MakeDir(name string) os.Error {
// todo
return nil
}
func (c *ServerConn) RemoveDir(name string) os.Error {
return nil
}
// Sends a NOOP command. Usualy used to prevent timeouts.
func (c *ServerConn) NoOp() os.Error {
_, err := c.conn.Cmd("NOOP")
if err != nil {
return err
}
_, _, err = c.conn.ReadCodeLine(StatusCommandOK)
return err
}
func (c *ServerConn) Quit() os.Error {
c.conn.Cmd("QUIT")
c.conn.Close()
return c.conn.Close()
}
func (r *Response) Read(buf []byte) (int, os.Error) {
func (r *response) Read(buf []byte) (int, os.Error) {
n, err := r.conn.Read(buf)
if err == os.EOF {
_, _, err2 := r.c.conn.ReadCodeLine(StatusClosingDataConnection)
@@ -190,6 +294,6 @@ func (r *Response) Read(buf []byte) (int, os.Error) {
return n, err
}
func (r *Response) Close() os.Error {
func (r *response) Close() os.Error {
return r.conn.Close()
}