Fix lint issues, remove unused code, and update to newer APIs

Add golangci-lint v2 config. Replace dot imports of generics with named
imports. Use keyed struct literals throughout. Replace deprecated
reflect.SliceHeader with unsafe.Slice, ioutil with os, and Magnet with
MagnetV2. Replace MakeMapIfNilAndSet with MakeMapIfNil+MapInsert. Fix
missing error checks in tracker HTTP client and webtorrent transport.
Fix sync.Pool type assertion for pointer types. Remove unused functions,
types, and struct fields across the codebase.

Author: anacrolix

.golangci.yml

@@ -0,0 +1,20 @@
+version: "2"
+
+linters:
+  disable:
+    - errcheck
+  settings:
+    govet:
+      disable:
+        - composites
+    staticcheck:
+      checks:
+        - "all"
+        - "-ST1000"
+        - "-ST1003"
+        - "-ST1016"
+        - "-ST1020"
+        - "-ST1021"
+        - "-ST1022"
+        - "-ST1023"
+        - "-QF1008"

analysis/peer-upload-order.go

@@ -53,19 +53,10 @@ func (me *PeerUploadOrder) Install(cbs *torrent.Callbacks) {
 	cbs.DeletedRequest = append(cbs.DeletedRequest, me.deletedRequest)
 }
 
-func (me *PeerUploadOrder) report(desc string, req torrent.Request, peer *torrent.Peer) {
-	peerConn, ok := peer.TryAsPeerConn()
-	var peerId *torrent.PeerID
-	if ok {
-		peerId = &peerConn.PeerID
-	}
-	log.Printf("%s: %v, %v", desc, req, peerId)
-}
-
 func (me *PeerUploadOrder) onReceivedRequested(event torrent.PeerMessageEvent) {
 	req := torrent.Request{
-		event.Message.Index,
-		torrent.ChunkSpec{
+		Index: event.Message.Index,
+		ChunkSpec: torrent.ChunkSpec{
 			Begin:  event.Message.Begin,
 			Length: pp.Integer(len(event.Message.Piece)),
 		},

bencode/decode.go

@@ -458,7 +458,7 @@ func (d *Decoder) parseDict(v reflect.Value) error {
 		ok, err = d.parseValue(setValue)
 		if err != nil {
 			var target *UnmarshalTypeError
-			if !(errors.As(err, &target) && df.Tags.IgnoreUnmarshalTypeError()) {
+			if !errors.As(err, &target) || !df.Tags.IgnoreUnmarshalTypeError() {
 				return fmt.Errorf("parsing value for key %q: %w", keyValue, err)
 			}
 		}

client-stats.go

@@ -7,7 +7,8 @@ import (
 )
 
 func setAdd[K comparable](m *map[K]struct{}, elem K) {
-	g.MakeMapIfNilAndSet(m, elem, struct{}{})
+	g.MakeMapIfNil(m)
+	g.MapInsert(*m, elem, struct{}{})
 }
 
 type clientHolepunchAddrSets struct {

client.go

@@ -26,7 +26,6 @@ import (
 	"github.com/anacrolix/chansync/events"
 	"github.com/anacrolix/dht/v2"
 	"github.com/anacrolix/dht/v2/krpc"
-	. "github.com/anacrolix/generics"
 	g "github.com/anacrolix/generics"
 	"github.com/anacrolix/generics/heap"
 	"github.com/anacrolix/log"
@@ -46,7 +45,6 @@ import (
 
 	"github.com/anacrolix/torrent/bencode"
 	"github.com/anacrolix/torrent/internal/check"
-	"github.com/anacrolix/torrent/internal/limiter"
 	"github.com/anacrolix/torrent/iplist"
 	"github.com/anacrolix/torrent/metainfo"
 	"github.com/anacrolix/torrent/mse"
@@ -110,7 +108,6 @@ type Client struct {
 
 	numWebSeedRequests map[webseedHostKeyHandle]int
 
-	activeAnnounceLimiter limiter.Instance
 	// TODO: Move this onto ClientConfig.
 	httpClient *http.Client
 
@@ -564,11 +561,6 @@ func (cl *Client) ipBlockRange(ip net.IP) (r iplist.Range, blocked bool) {
 	return cl.ipBlockList.Lookup(ip)
 }
 
-func (cl *Client) ipIsBlocked(ip net.IP) bool {
-	_, blocked := cl.ipBlockRange(ip)
-	return blocked
-}
-
 func (cl *Client) wantConns() bool {
 	if cl.config.AlwaysWantConns {
 		return true
@@ -868,7 +860,8 @@ func (cl *Client) dialAndCompleteHandshake(opts outgoingConnOpts) (c *PeerConn,
 		if holepunchAddrErr == nil {
 			cl.lock()
 			if !opts.receivedHolepunchConnect {
-				g.MakeMapIfNilAndSet(&cl.undialableWithoutHolepunch, holepunchAddr, struct{}{})
+				g.MakeMapIfNil(&cl.undialableWithoutHolepunch)
+				g.MapInsert(cl.undialableWithoutHolepunch, holepunchAddr, struct{}{})
 			}
 			if !opts.skipHolepunchRendezvous {
 				opts.t.trySendHolepunchRendezvous(holepunchAddr)
@@ -881,7 +874,8 @@ func (cl *Client) dialAndCompleteHandshake(opts outgoingConnOpts) (c *PeerConn,
 	if opts.receivedHolepunchConnect && holepunchAddrErr == nil {
 		cl.lock()
 		if g.MapContains(cl.undialableWithoutHolepunch, holepunchAddr) {
-			g.MakeMapIfNilAndSet(&cl.dialableOnlyAfterHolepunch, holepunchAddr, struct{}{})
+			g.MakeMapIfNil(&cl.dialableOnlyAfterHolepunch)
+			g.MapInsert(cl.dialableOnlyAfterHolepunch, holepunchAddr, struct{}{})
 		}
 		g.MakeMapIfNil(&cl.dialedSuccessfullyAfterHolepunchConnect)
 		g.MapInsert(cl.dialedSuccessfullyAfterHolepunchConnect, holepunchAddr, struct{}{})
@@ -1763,7 +1757,7 @@ func (cl *Client) newConnection(nc net.Conn, opts newConnectionOpts) (c *PeerCon
 	if opts.remoteAddr != nil {
 		netipAddrPort, err := netip.ParseAddrPort(opts.remoteAddr.String())
 		if err == nil {
-			c.bannableAddr = Some(netipAddrPort.Addr())
+			c.bannableAddr = g.Some(netipAddrPort.Addr())
 		}
 	}
 	c.legacyPeerImpl = c

client_test.go

@@ -708,7 +708,9 @@ func makeMagnet(t *testing.T, cl *Client, dir, name string) string {
 	require.NoError(t, err)
 	mi.InfoBytes, err = bencode.Marshal(info)
 	require.NoError(t, err)
-	magnet := mi.Magnet(nil, &info).String()
+	m, err := mi.MagnetV2()
+	require.NoError(t, err)
+	magnet := m.String()
 	tr, err := cl.AddTorrent(&mi)
 	require.NoError(t, err)
 	require.True(t, tr.Seeding())
@@ -923,7 +925,7 @@ func TestDroppedTorrentsNotReturned(t *testing.T) {
 	qt.Check(t, qt.Equals(tt1, tt))
 	qt.Check(t, qt.SliceContains(cl.Torrents(), tt))
 	tt.Drop()
-	tt1, ok = cl.Torrent(tt.InfoHash())
+	_, ok = cl.Torrent(tt.InfoHash())
 	qt.Check(t, qt.IsFalse(ok))
 	qt.Check(t, qt.HasLen(cl.Torrents(), 0))
 }

cmd/torrent/announce.go

@@ -8,13 +8,14 @@ import (
 	"github.com/anacrolix/torrent"
 	"github.com/anacrolix/torrent/tracker"
 	"github.com/anacrolix/torrent/tracker/udp"
+	"github.com/anacrolix/torrent/types/infohash"
 )
 
 type AnnounceCmd struct {
 	Event    udp.AnnounceEvent
 	Port     *uint16
-	Tracker  string           `arg:"positional"`
-	InfoHash torrent.InfoHash `arg:"positional"`
+	Tracker  string     `arg:"positional"`
+	InfoHash infohash.T `arg:"positional"`
 }
 
 func announceErr(flags AnnounceCmd) error {

cmd/torrent/download.go

@@ -82,55 +82,6 @@ func clientStatusWriter(ctx context.Context, cl *torrent.Client) {
 	}
 }
 
-// Keeping this for now for reference in case I do per-torrent deltas in client status updates.
-func torrentBar(t *torrent.Torrent, pieceStates bool) {
-	go func() {
-		start := time.Now()
-		if t.Info() == nil {
-			fmt.Printf("%v: getting torrent info for %q\n", time.Since(start), t.Name())
-			<-t.GotInfo()
-		}
-		lastStats := t.Stats()
-		var lastLine string
-		interval := 3 * time.Second
-		for range time.Tick(interval) {
-			var completedPieces, partialPieces int
-			psrs := t.PieceStateRuns()
-			for _, r := range psrs {
-				if r.Complete {
-					completedPieces += r.Length
-				}
-				if r.Partial {
-					partialPieces += r.Length
-				}
-			}
-			stats := t.Stats()
-			byteRate := int64(time.Second)
-			byteRate *= stats.BytesReadUsefulData.Int64() - lastStats.BytesReadUsefulData.Int64()
-			byteRate /= int64(interval)
-			line := fmt.Sprintf(
-				"%v: downloading %q: %s/%s, %d/%d pieces completed (%d partial): %v/s\n",
-				time.Since(start),
-				t.Name(),
-				humanize.Bytes(uint64(t.BytesCompleted())),
-				humanize.Bytes(uint64(t.Length())),
-				completedPieces,
-				t.NumPieces(),
-				partialPieces,
-				humanize.Bytes(uint64(byteRate)),
-			)
-			if line != lastLine {
-				lastLine = line
-				os.Stdout.WriteString(line)
-			}
-			if pieceStates {
-				fmt.Println(psrs)
-			}
-			lastStats = stats
-		}
-	}()
-}
-
 type stringAddr string
 
 func (stringAddr) Network() string   { return "" }
@@ -173,7 +124,7 @@ func addTorrents(
 				metaInfo, err := metainfo.Load(response.Body)
 				defer response.Body.Close()
 				if err != nil {
-					return nil, fmt.Errorf("error loading torrent file %q: %s\n", arg, err)
+					return nil, fmt.Errorf("error loading torrent file %q: %s", arg, err)
 				}
 				t, err := client.AddTorrent(metaInfo)
 				if err != nil {
@@ -186,7 +137,7 @@ func addTorrents(
 			} else {
 				metaInfo, err := metainfo.LoadFromFile(arg)
 				if err != nil {
-					return nil, fmt.Errorf("error loading torrent file %q: %s\n", arg, err)
+					return nil, fmt.Errorf("error loading torrent file %q: %s", arg, err)
 				}
 				t, err := client.AddTorrent(metaInfo)
 				if err != nil {

cmd/torrent/main.go

@@ -15,7 +15,7 @@ import (
 	"github.com/anacrolix/envpprof"
 	app "github.com/anacrolix/gostdapp"
 	"github.com/anacrolix/log"
-	xprometheus "github.com/anacrolix/missinggo/v2/prometheus"
+	expvar_prometheus "github.com/anacrolix/missinggo/v2/expvar-prometheus"
 
 	"github.com/davecgh/go-spew/spew"
 	"github.com/prometheus/client_golang/prometheus"
@@ -27,10 +27,10 @@ import (
 
 func init() {
 	stdLog.SetFlags(stdLog.Flags() | stdLog.Lshortfile)
-	prometheus.MustRegister(xprometheus.NewExpvarCollector())
+	prometheus.MustRegister(expvar_prometheus.NewCollector())
 	http.Handle("/metrics", promhttp.Handler())
 	log.Default = log.NewLogger().WithDefaultLevel(log.Info)
-	log.Default.SetHandlers(log.SlogHandlerAsHandler{slog.Default().Handler()})
+	log.Default.SetHandlers(log.SlogHandlerAsHandler{SlogHandler: slog.Default().Handler()})
 }
 
 func main() {

cmd/torrent/scrape.go

@@ -6,13 +6,13 @@ import (
 
 	"github.com/davecgh/go-spew/spew"
 
-	"github.com/anacrolix/torrent"
 	"github.com/anacrolix/torrent/tracker"
+	"github.com/anacrolix/torrent/types/infohash"
 )
 
 type scrapeCfg struct {
-	Tracker    string             `arg:"positional"`
-	InfoHashes []torrent.InfoHash `arity:"+" arg:"positional"`
+	Tracker    string       `arg:"positional"`
+	InfoHashes []infohash.T `arity:"+" arg:"positional"`
 }
 
 func scrape(flags scrapeCfg) error {