Initial sACN library with protocol, sender, receiver, and discovery

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
2026-01-28 21:36:34 -08:00
commit d5ca321a4c
7 changed files with 742 additions and 0 deletions
--- a/fuzz_test.go
+++ b/fuzz_test.go
@@ -0,0 +1,107 @@
+package sacn
+
+import (
+	"bytes"
+	"testing"
+)
+
+func FuzzParsePacket(f *testing.F) {
+	cid := [16]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+	validPacket := BuildDataPacket(1, 0, "test", cid, make([]byte, 512))
+	f.Add(validPacket)
+	f.Add(BuildDataPacket(1, 0, "test", cid, make([]byte, 100)))
+	f.Add(BuildDataPacket(63999, 255, "long source name here", cid, make([]byte, 512)))
+	f.Add(BuildDiscoveryPacket("test", cid, 0, 0, []uint16{1, 2, 3}))
+	f.Add([]byte{})
+	f.Add(make([]byte, 125))
+	f.Add(make([]byte, 126))
+	f.Add(make([]byte, 638))
+
+	f.Fuzz(func(t *testing.T, data []byte) {
+		pkt, err := ParsePacket(data)
+		if err != nil {
+			return
+		}
+		switch p := pkt.(type) {
+		case *DataPacket:
+			if p.DataLen > 512 {
+				t.Fatalf("data length should be <= 512, got %d", p.DataLen)
+			}
+		case *DiscoveryPacket:
+			for _, u := range p.Universes {
+				if u < 1 || u > 63999 {
+					t.Fatalf("universe out of range: %d", u)
+				}
+			}
+		}
+	})
+}
+
+func FuzzBuildParseRoundtrip(f *testing.F) {
+	f.Add(uint16(1), uint8(0), "test", make([]byte, 512))
+	f.Add(uint16(63999), uint8(255), "source", make([]byte, 100))
+	f.Add(uint16(100), uint8(128), "", make([]byte, 0))
+	f.Add(uint16(1), uint8(0), "a very long source name that exceeds normal limits", make([]byte, 512))
+
+	f.Fuzz(func(t *testing.T, universe uint16, seq uint8, sourceName string, dmxInput []byte) {
+		if universe < 1 || universe > 63999 {
+			return
+		}
+		cid := [16]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+		packet := BuildDataPacket(universe, seq, sourceName, cid, dmxInput)
+		pkt, err := ParsePacket(packet)
+		if err != nil {
+			t.Fatalf("failed to parse packet we just built: %v", err)
+		}
+		dataPkt, ok := pkt.(*DataPacket)
+		if !ok {
+			t.Fatalf("expected DataPacket, got %T", pkt)
+		}
+		if dataPkt.Universe != universe {
+			t.Fatalf("universe mismatch: sent %d, got %d", universe, dataPkt.Universe)
+		}
+		expectedLen := len(dmxInput)
+		if expectedLen > 512 {
+			expectedLen = 512
+		}
+		if !bytes.Equal(dataPkt.Data[:expectedLen], dmxInput[:expectedLen]) {
+			t.Fatalf("dmx data mismatch")
+		}
+	})
+}
+
+func FuzzDiscoveryRoundtrip(f *testing.F) {
+	f.Add("test", uint8(0), uint8(0), []byte{0, 1, 0, 2, 0, 3})
+
+	f.Fuzz(func(t *testing.T, sourceName string, page, lastPage uint8, universeBytes []byte) {
+		universes := make([]uint16, 0, len(universeBytes)/2)
+		for i := 0; i+1 < len(universeBytes); i += 2 {
+			u := uint16(universeBytes[i])<<8 | uint16(universeBytes[i+1])
+			if u >= 1 && u <= 63999 {
+				universes = append(universes, u)
+			}
+		}
+		if len(universes) == 0 {
+			return
+		}
+		cid := [16]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
+		packet := BuildDiscoveryPacket(sourceName, cid, page, lastPage, universes)
+		pkt, err := ParsePacket(packet)
+		if err != nil {
+			t.Fatalf("failed to parse discovery packet: %v", err)
+		}
+		discPkt, ok := pkt.(*DiscoveryPacket)
+		if !ok {
+			t.Fatalf("expected DiscoveryPacket, got %T", pkt)
+		}
+		if discPkt.Page != page {
+			t.Fatalf("page mismatch: sent %d, got %d", page, discPkt.Page)
+		}
+		if discPkt.LastPage != lastPage {
+			t.Fatalf("lastPage mismatch: sent %d, got %d", lastPage, discPkt.LastPage)
+		}
+		if len(discPkt.Universes) != len(universes) {
+			t.Fatalf("universe count mismatch: sent %d, got %d", len(universes), len(discPkt.Universes))
+		}
+	})
+}