fix(radio): address ICY parser review feedback

Signed-off-by: hiyukoim <11803292+hiyukoim@users.noreply.github.com>

core/radio/icy/parser.go

@@ -17,17 +17,22 @@ var (
 	errEndOfStream         = errors.New("icy stream ended")
 )
 
+const (
+	maxMetaInt     = 1024 * 1024
+	maxMetadataLen = 255 * 16
+)
+
 // ReadStreamTitles reads ICY metadata blocks from r and emits changed StreamTitle values.
 func ReadStreamTitles(ctx context.Context, r io.Reader, metaInt int, handleTitle func(string)) error {
-	if metaInt <= 0 {
+	if metaInt <= 0 || metaInt > maxMetaInt {
 		return ErrInvalidMetaInt
 	}
 	if handleTitle == nil {
 		return ErrMissingTitleHandler
 	}
 
-	audio := make([]byte, metaInt)
 	length := make([]byte, 1)
+	metadataBuf := make([]byte, maxMetadataLen)
 	lastTitle := ""
 
 	for {
@@ -35,8 +40,8 @@ func ReadStreamTitles(ctx context.Context, r io.Reader, metaInt int, handleTitle
 			return err
 		}
 
-		if err := readFullOrEnd(r, audio); err != nil {
-			if errors.Is(err, errEndOfStream) {
+		if _, err := io.CopyN(io.Discard, r, int64(metaInt)); err != nil {
+			if errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF) {
 				return nil
 			}
 			return err
@@ -58,7 +63,7 @@ func ReadStreamTitles(ctx context.Context, r io.Reader, metaInt int, handleTitle
 			continue
 		}
 
-		metadata := make([]byte, metadataLen)
+		metadata := metadataBuf[:metadataLen]
 		if err := readFullOrEnd(r, metadata); err != nil {
 			if errors.Is(err, errEndOfStream) {
 				return nil
@@ -96,9 +101,12 @@ func streamTitle(metadata []byte) string {
 	}
 
 	start += len(prefix)
-	end := strings.IndexByte(text[start:], '\'')
+	end := strings.Index(text[start:], "';")
 	if end < 0 {
-		return ""
+		end = strings.IndexByte(text[start:], '\'')
+		if end < 0 {
+			return ""
+		}
 	}
 
 	return strings.TrimSpace(text[start : start+end])

core/radio/icy/parser_test.go

@@ -73,6 +73,22 @@ var _ = Describe("ReadStreamTitles", func() {
 		Expect(titles).To(BeEmpty())
 	})
 
+	It("returns an error for huge metadata intervals", func() {
+		titles, err := readTitles(context.Background(), nil, maxMetaInt+1)
+
+		Expect(err).To(MatchError(ErrInvalidMetaInt))
+		Expect(titles).To(BeEmpty())
+	})
+
+	It("keeps single quotes inside StreamTitle values", func() {
+		stream := icyStream(metaInt, "StreamTitle='L'Oiseau - Track';")
+
+		titles, err := readTitles(context.Background(), stream, metaInt)
+
+		Expect(err).ToNot(HaveOccurred())
+		Expect(titles).To(Equal([]string{"L'Oiseau - Track"}))
+	})
+
 	It("stops when context is cancelled", func() {
 		ctx, cancel := context.WithCancel(context.Background())
 		cancel()

core/radio/provider.go

@@ -35,7 +35,7 @@ func NewMetadataManagerService(publisher TitlePublisher) *MetadataManager {
 // ICY metadata or a client-error HTTP status — so the reader backs off for
 // much longer instead of hammering the station.
 func classifyICYError(err error) error {
-	if errors.Is(err, icy.ErrMissingMetaInt) {
+	if errors.Is(err, icy.ErrMissingMetaInt) || errors.Is(err, icy.ErrInvalidMetaInt) {
 		return MarkPermanent(err)
 	}
 	var statusErr *icy.ResponseStatusError

core/radio/provider_test.go

@@ -0,0 +1,20 @@
+package radio
+
+import (
+	"fmt"
+
+	"github.com/navidrome/navidrome/core/radio/icy"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Metadata provider", func() {
+	Describe("classifyICYError", func() {
+		It("marks invalid metadata intervals as permanent", func() {
+			err := classifyICYError(fmt.Errorf("%w: %q", icy.ErrInvalidMetaInt, "999999999"))
+
+			Expect(isPermanent(err)).To(BeTrue())
+			Expect(err).To(MatchError(ContainSubstring(icy.ErrInvalidMetaInt.Error())))
+		})
+	})
+})