package torrent
import (
- "crypto"
"errors"
- "fmt"
- "time"
+ "net"
+ "github.com/RoaringBitmap/roaring"
+ "github.com/anacrolix/missinggo/v2"
+ "golang.org/x/time/rate"
+
+ "github.com/anacrolix/torrent/metainfo"
pp "github.com/anacrolix/torrent/peer_protocol"
+ "github.com/anacrolix/torrent/types"
+ "github.com/anacrolix/torrent/types/infohash"
)
-const (
- pieceHash = crypto.SHA1
- maxRequests = 250 // Maximum pending requests we allow peers to send us.
- chunkSize = 0x4000 // 16KiB
- bep20 = "-GT0000-" // Peer ID client identifier prefix
- nominalDialTimeout = time.Second * 30
- minDialTimeout = 5 * time.Second
+type (
+ Request = types.Request
+ ChunkSpec = types.ChunkSpec
+ piecePriority = types.PiecePriority
)
-type (
- InfoHash [20]byte
- pieceSum [20]byte
+const (
+ PiecePriorityNormal = types.PiecePriorityNormal
+ PiecePriorityNone = types.PiecePriorityNone
+ PiecePriorityNow = types.PiecePriorityNow
+ PiecePriorityReadahead = types.PiecePriorityReadahead
+ PiecePriorityNext = types.PiecePriorityNext
+ PiecePriorityHigh = types.PiecePriorityHigh
)
-func (ih *InfoHash) AsString() string {
- return string(ih[:])
+func newRequest(index, begin, length pp.Integer) Request {
+ return Request{index, ChunkSpec{begin, length}}
}
-func (ih *InfoHash) HexString() string {
- return fmt.Sprintf("%x", ih[:])
+func newRequestFromMessage(msg *pp.Message) Request {
+ switch msg.Type {
+ case pp.Request, pp.Cancel, pp.Reject:
+ return newRequest(msg.Index, msg.Begin, msg.Length)
+ case pp.Piece:
+ return newRequest(msg.Index, msg.Begin, pp.Integer(len(msg.Piece)))
+ default:
+ panic(msg.Type)
+ }
+}
+
+// The size in bytes of a metadata extension piece.
+func metadataPieceSize(totalSize, piece int) int {
+ ret := totalSize - piece*(1<<14)
+ if ret > 1<<14 {
+ ret = 1 << 14
+ }
+ return ret
}
-func lastChunkSpec(pieceLength pp.Integer) (cs chunkSpec) {
- cs.Begin = (pieceLength - 1) / chunkSize * chunkSize
- cs.Length = pieceLength - cs.Begin
+// Return the request that would include the given offset into the torrent data.
+func torrentOffsetRequest(
+ torrentLength, pieceSize, chunkSize, offset int64,
+) (
+ r Request, ok bool,
+) {
+ if offset < 0 || offset >= torrentLength {
+ return
+ }
+ r.Index = pp.Integer(offset / pieceSize)
+ r.Begin = pp.Integer(offset % pieceSize / chunkSize * chunkSize)
+ r.Length = pp.Integer(chunkSize)
+ pieceLeft := pp.Integer(pieceSize - int64(r.Begin))
+ if r.Length > pieceLeft {
+ r.Length = pieceLeft
+ }
+ torrentLeft := torrentLength - int64(r.Index)*pieceSize - int64(r.Begin)
+ if int64(r.Length) > torrentLeft {
+ r.Length = pp.Integer(torrentLeft)
+ }
+ ok = true
return
}
-type chunkSpec struct {
- Begin, Length pp.Integer
+func torrentRequestOffset(torrentLength, pieceSize int64, r Request) (off int64) {
+ off = int64(r.Index)*pieceSize + int64(r.Begin)
+ if off < 0 || off >= torrentLength {
+ panic("invalid Request")
+ }
+ return
}
-type request struct {
- Index pp.Integer
- chunkSpec
+func validateInfo(info *metainfo.Info) error {
+ if len(info.Pieces)%20 != 0 {
+ return errors.New("pieces has invalid length")
+ }
+ if info.PieceLength == 0 {
+ if info.TotalLength() != 0 {
+ return errors.New("zero piece length")
+ }
+ } else {
+ if int((info.TotalLength()+info.PieceLength-1)/info.PieceLength) != info.NumPieces() {
+ return errors.New("piece count and file lengths are at odds")
+ }
+ }
+ return nil
}
-func newRequest(index, begin, length pp.Integer) request {
- return request{index, chunkSpec{begin, length}}
+func chunkIndexSpec(index, pieceLength, chunkSize pp.Integer) ChunkSpec {
+ ret := ChunkSpec{pp.Integer(index) * chunkSize, chunkSize}
+ if ret.Begin+ret.Length > pieceLength {
+ ret.Length = pieceLength - ret.Begin
+ }
+ return ret
}
-var (
- // Requested data not yet available.
- errDataNotReady = errors.New("data not ready")
-)
+func connLessTrusted(l, r *Peer) bool {
+ return l.trust().Less(r.trust())
+}
-// The size in bytes of a metadata extension piece.
-func metadataPieceSize(totalSize int, piece int) int {
- ret := totalSize - piece*(1<<14)
- if ret > 1<<14 {
- ret = 1 << 14
+func connIsIpv6(nc interface {
+ LocalAddr() net.Addr
+},
+) bool {
+ ra := nc.LocalAddr()
+ rip := addrIpOrNil(ra)
+ return rip.To4() == nil && rip.To16() != nil
+}
+
+func clamp(min, value, max int64) int64 {
+ if min > max {
+ panic("harumph")
+ }
+ if value < min {
+ value = min
+ }
+ if value > max {
+ value = max
+ }
+ return value
+}
+
+func max(as ...int64) int64 {
+ ret := as[0]
+ for _, a := range as[1:] {
+ if a > ret {
+ ret = a
+ }
+ }
+ return ret
+}
+
+func maxInt(as ...int) int {
+ ret := as[0]
+ for _, a := range as[1:] {
+ if a > ret {
+ ret = a
+ }
}
return ret
}
-type superer interface {
- Super() interface{}
+func min(as ...int64) int64 {
+ ret := as[0]
+ for _, a := range as[1:] {
+ if a < ret {
+ ret = a
+ }
+ }
+ return ret
}
-// Returns ok if there's a parent, and it's not nil.
-func super(child interface{}) (parent interface{}, ok bool) {
- s, ok := child.(superer)
- if !ok {
- return
+func minInt(as ...int) int {
+ ret := as[0]
+ for _, a := range as[1:] {
+ if a < ret {
+ ret = a
+ }
+ }
+ return ret
+}
+
+var unlimited = rate.NewLimiter(rate.Inf, 0)
+
+type (
+ pieceIndex = int
+ // Deprecated: Use infohash.T directly to avoid unnecessary imports.
+ InfoHash = infohash.T
+ IpPort = missinggo.IpPort
+)
+
+func boolSliceToBitmap(slice []bool) (rb roaring.Bitmap) {
+ for i, b := range slice {
+ if b {
+ rb.AddInt(i)
+ }
}
- parent = s.Super()
- ok = parent != nil
return
}