staticcheck guided refactoring

Makefile

@@ -9,6 +9,8 @@ magneticow:
 	# TODO: minify files!
 	# https://github.com/kevinburke/go-bindata
 	go-bindata -o="cmd/magneticow/bindata.go" -prefix="cmd/magneticow/data/" cmd/magneticow/data/...
+	# Prepend the linter instruction to the beginning of the file
+	sed -i '1s;^;//lint:file-ignore * Ignore file altogether\n;' cmd/magneticow/bindata.go
 	go install --tags fts5 "-ldflags=-s -w -X main.compiledOn=`date -u +%Y-%m-%dT%H:%M:%SZ`" ./cmd/magneticow
 
 .PHONY: docker
@@ -38,7 +40,7 @@ vet:
 	go vet ./...
 
 staticcheck:
-	./misc/staticcheck/staticcheck ./...
+	./misc/staticcheck/staticcheck -fail all ./...
 
 test:
 	go test ./...

cmd/magneticod/bittorrent/metadata/leech.go

@@ -471,7 +471,7 @@ func toBigEndian(i uint, n int) []byte {
 		binary.BigEndian.PutUint32(b, uint32(i))
 
 	default:
-		panic(fmt.Sprintf("n must be 1, 2, or 4!"))
+		panic("n must be 1, 2, or 4!")
 	}
 
 	if len(b) != n {

cmd/magneticod/dht/mainline/codec.go

@@ -273,7 +273,7 @@ func (e *Error) UnmarshalBencode(b []byte) (err error) {
 	}
 
 	if len(matches[2]) != msgLen {
-		return fmt.Errorf("error message have different lengths (%d vs %d) \"%s\"!", len(matches[2]), msgLen, matches[2])
+		return fmt.Errorf("error message have different lengths (%d vs %d) \"%s\"", len(matches[2]), msgLen, matches[2])
 	}
 
 	e.Code = code

cmd/magneticod/dht/mainline/protocol.go

@@ -327,6 +327,7 @@ func validatePingORannouncePeerResponseMessage(msg *Message) bool {
 }
 
 func validateFindNodeResponseMessage(msg *Message) bool {
+	//lint:ignore S1008 to be done later
 	if len(msg.R.ID) != 20 {
 		return false
 	}

cmd/magneticow/handlers.go

@@ -39,7 +39,6 @@ func torrentsInfohashHandler(w http.ResponseWriter, r *http.Request) {
 	// Cache static resources for a day
 	w.Header().Set("Cache-Control", "max-age=86400")
 	_, _ = w.Write(data)
-	return
 }
 
 func statisticsHandler(w http.ResponseWriter, r *http.Request) {

pkg/persistence/sqlite3.go

@@ -218,8 +218,8 @@ func (db *sqlite3Database) GetNumberOfTorrents() (uint, error) {
 	}
 	defer rows.Close()
 
-	if rows.Next() != true {
-		return 0, fmt.Errorf("No rows returned from `SELECT MAX(ROWID)`")
+	if !rows.Next() {
+		return 0, fmt.Errorf("no rows returned from `SELECT MAX(ROWID)`")
 	}
 
 	var n *uint
@@ -384,7 +384,7 @@ func (db *sqlite3Database) GetTorrent(infoHash []byte) (*TorrentMetadata, error)
 		return nil, err
 	}
 
-	if rows.Next() != true {
+	if !rows.Next() {
 		return nil, nil
 	}
 
@@ -547,8 +547,8 @@ func (db *sqlite3Database) setupDatabase() error {
 	}
 	defer rows.Close()
 	var userVersion int
-	if rows.Next() != true {
-		return fmt.Errorf("sql.Rows.Next (user_version): PRAGMA user_version did not return any rows!")
+	if !rows.Next() {
+		return fmt.Errorf("sql.Rows.Next (user_version): PRAGMA user_version did not return any rows")
 	}
 	if err = rows.Scan(&userVersion); err != nil {
 		return errors.Wrap(err, "sql.Rows.Scan (user_version)")