Initialize the repo

bitfield/bitfield.go

@@ -0,0 +1,3 @@
+package bitfield
+
+type Bitfield []byte

client/client.go

@@ -0,0 +1,33 @@
+package client
+
+import (
+	"BitTorrent-Client/bitfield"
+	"BitTorrent-Client/peers"
+	"net"
+	"time"
+)
+
+type Client struct {
+	Conn     net.Conn
+	Choked   bool
+	Bitfield bitfield.Bitfield
+	peer     peers.Peer
+	infoHash [20]byte
+	peerID   [20]byte
+}
+
+func New(peer peers.Peer, peerID, infoHash [20]byte) (*Client, error) {
+	conn, err := net.DialTimeout("tcp", peer.String(), 3*time.Second)
+	if err != nil {
+		return nil, err
+	}
+	return &Client{
+		Conn:     conn,
+		Choked:   true,
+		peer:     peer,
+		infoHash: infoHash,
+		peerID:   peerID,
+	}, nil
+}
+
+// Read reads and consumes a message from the connection

hand_shake/hand_shake.go

@@ -0,0 +1,20 @@
+package handshake
+
+// A Handshake is a special message that a peer uses to identify itself
+type Handshake struct {
+	Pstr     string
+	InfoHash [20]byte
+	PeerID   [20]byte
+}
+
+// Serialize serializes the handshake to a buffer
+func (h *Handshake) Serialize() []byte {
+	buf := make([]byte, len(h.Pstr)+49)
+	buf[0] = byte(len(h.Pstr))
+	curr := 1
+	curr += copy(buf[curr:], h.Pstr)
+	curr += copy(buf[curr:], make([]byte, 8)) // 8 reserved bytes
+	curr += copy(buf[curr:], h.InfoHash[:])
+	curr += copy(buf[curr:], h.PeerID[:])
+	return buf
+}

main.go

@@ -0,0 +1,17 @@
+package main
+
+import (
+	torrentfile "BitTorrent-Client/torrent_file"
+	"log"
+	"os"
+)
+
+func main() {
+	inPath := os.Args[1]
+
+	_, err := torrentfile.Open(inPath)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+}

peers/peers.go

@@ -4,6 +4,7 @@ import (
 	"encoding/binary"
 	"fmt"
 	"net"
+	"strconv"
 )
 
 type Peer struct {
@@ -27,3 +28,6 @@ func Unmarshal(peersBin []byte) ([]Peer, error) {
 	}
 	return peers, nil
 }
+func (p Peer) String() string {
+	return net.JoinHostPort(p.IP.String(), strconv.Itoa(int(p.Port)))
+}

torrent_file/torrent_file.go

@@ -1,7 +1,7 @@
 package torrentfile
 
 import (
-	"io"
+	"os"
 
 	"github.com/jackpal/bencode-go"
 )
@@ -29,11 +29,15 @@ type bencodeTorrent struct {
 }
 
 // Open parses a torrent file
-func Open(r io.Reader) (*bencodeTorrent, error) {
-	bto := bencodeTorrent{}
-	err := bencode.Unmarshal(r, &bto)
+func Open(path string) (TorrentFile, error) {
+	file, err := os.Open(path)
 	if err != nil {
-		return nil, err
+		return TorrentFile{}, err
 	}
-	return &bto, nil
+	defer file.Close()
+
+	bto := bencodeTorrent{}
+	err = bencode.Unmarshal(file, &bto)
+	return TorrentFile{}, err
+
 }