fix array decoding #509

pkg/demoinfocs/datatables.go

@@ -703,7 +703,7 @@ func (p *parser) bindPlayerWeapons(playerEntity st.Entity, pl *common.Player) {
 func (p *parser) bindPlayerWeaponsS2(pawnEntity st.Entity, pl *common.Player) {
 	const inventoryCapacity = 64
 
-	var inventorySize uint64 = 64
+	inventorySize := 64
 
 	type eq struct {
 		*common.Equipment
@@ -728,7 +728,7 @@ func (p *parser) bindPlayerWeaponsS2(pawnEntity st.Entity, pl *common.Player) {
 	setPlayerInventory := func() {
 		inventory := make(map[int]*common.Equipment, inventorySize)
 
-		for i := uint64(0); i < inventorySize; i++ {
+		for i := 0; i < inventorySize; i++ {
 			val := pawnEntity.Property(playerWeaponPrefixS2 + fmt.Sprintf("%04d", i)).Value()
 			if val.Any == nil {
 				continue
@@ -742,7 +742,7 @@ func (p *parser) bindPlayerWeaponsS2(pawnEntity st.Entity, pl *common.Player) {
 	}
 
 	pawnEntity.Property("m_pWeaponServices.m_hMyWeapons").OnUpdate(func(pv st.PropertyValue) {
-		inventorySize = pv.S2UInt64()
+		inventorySize = len(pv.S2Array())
 		setPlayerInventory()
 	})
 
@@ -758,7 +758,7 @@ func (p *parser) bindPlayerWeaponsS2(pawnEntity st.Entity, pl *common.Player) {
 
 			entityWasCreated := entityID != constants.EntityHandleIndexMaskSource2
 
-			if uint64(i) < inventorySize {
+			if i < inventorySize {
 				if entityWasCreated {
 					existingWeapon, exists := playerInventory[i]
 					if exists {

pkg/demoinfocs/sendtables/propdecoder.go

@@ -152,6 +152,10 @@ func (v PropertyValue) S2UInt64() uint64 {
 	return v.Any.(uint64)
 }
 
+func (v PropertyValue) S2Array() []any {
+	return v.Any.([]any)
+}
+
 func (v PropertyValue) S2UInt32() uint32 {
 	return v.Any.(uint32)
 }

pkg/demoinfocs/sendtables2/entity.go

@@ -58,14 +58,21 @@ func (p property) Name() string {
 }
 
 func (p property) Value() st.PropertyValue {
+	v := p.entity.Get(p.name)
+
+	fs, ok := v.(*fieldState)
+	if ok {
+		v = fs.state
+	}
+
 	return st.PropertyValue{
 		VectorVal: r3.Vector{},
 		IntVal:    0,
 		Int64Val:  0,
 		ArrayVal:  nil,
 		StringVal: "",
 		FloatVal:  0,
-		Any:       p.entity.Get(p.name),
+		Any:       v,
 		S2:        true,
 	}
 }
@@ -416,12 +423,30 @@ func (e *Entity) readFields(r *reader, paths *[]*fieldPath) {
 	readFieldPaths(r, paths)
 
 	for _, fp := range *paths {
-		decoder := e.class.serializer.getDecoderForFieldPath(fp, 0)
+		f := e.class.serializer.getFieldForFieldPath(fp, 0)
+		name := e.class.getNameForFieldPath(fp)
+		decoder, base := e.class.serializer.getDecoderForFieldPath2(fp, 0)
 
 		val := decoder(r)
-		e.state.set(fp, val)
 
-		for _, h := range e.updateHandlers[e.class.getNameForFieldPath(fp)] {
+		if base && (f.model == fieldModelVariableArray || f.model == fieldModelVariableTable) {
+			oldFS := e.state.get(fp)
+			fs := newFieldState()
+
+			fs.state = make([]interface{}, val.(uint64))
+
+			if oldFS != nil {
+				copy(fs.state, oldFS.(*fieldState).state[:min(len(fs.state), len(oldFS.(*fieldState).state))])
+			}
+
+			e.state.set(fp, fs)
+
+			val = fs.state
+		} else {
+			e.state.set(fp, val)
+		}
+
+		for _, h := range e.updateHandlers[name] {
 			h(st.PropertyValue{
 				VectorVal: r3.Vector{},
 				IntVal:    0,
@@ -446,7 +471,7 @@ func (p *Parser) OnPacketEntities(m *msgs2.CSVCMsg_PacketEntities) error {
 		index   = int32(-1)
 		updates = int(m.GetUpdatedEntries())
 		cmd     uint32
-		classId int32
+		classID int32
 		serial  int32
 	)
 
@@ -485,18 +510,18 @@ func (p *Parser) OnPacketEntities(m *msgs2.CSVCMsg_PacketEntities) error {
 		}
 		if cmd&0x01 == 0 {
 			if cmd&0x02 != 0 {
-				classId = int32(r.readBits(p.classIdSize))
+				classID = int32(r.readBits(p.classIdSize))
 				serial = int32(r.readBits(17))
 				r.readVarUint32()
 
-				class := p.classesById[classId]
+				class := p.classesById[classID]
 				if class == nil {
-					_panicf("unable to find new class %d", classId)
+					_panicf("unable to find new class %d", classID)
 				}
 
-				baseline := p.classBaselines[classId]
+				baseline := p.classBaselines[classID]
 				if baseline == nil {
-					_panicf("unable to find new baseline %d", classId)
+					_panicf("unable to find new baseline %d", classID)
 				}
 
 				e = newEntity(index, serial, class)

pkg/demoinfocs/sendtables2/field.go

@@ -208,31 +208,34 @@ func (f *field) getTypeForFieldPath(fp *fieldPath, pos int) *fieldType {
 	return f.fieldType
 }
 
-func (f *field) getDecoderForFieldPath(fp *fieldPath, pos int) fieldDecoder {
+func (f *field) getDecoderForFieldPath(fp *fieldPath, pos int) (fieldDecoder, bool) {
 	switch f.model {
 	case fieldModelFixedArray:
-		return f.decoder
+		return f.decoder, false
 
 	case fieldModelFixedTable:
 		if fp.last == pos-1 {
-			return f.baseDecoder
+			return f.baseDecoder, true
 		}
-		return f.serializer.getDecoderForFieldPath(fp, pos)
+
+		return f.serializer.getDecoderForFieldPath2(fp, pos)
 
 	case fieldModelVariableArray:
 		if fp.last == pos {
-			return f.childDecoder
+			return f.childDecoder, false
 		}
-		return f.baseDecoder
+
+		return f.baseDecoder, true
 
 	case fieldModelVariableTable:
 		if fp.last >= pos+1 {
-			return f.serializer.getDecoderForFieldPath(fp, pos+1)
+			return f.serializer.getDecoderForFieldPath2(fp, pos+1)
 		}
-		return f.baseDecoder
+
+		return f.baseDecoder, true
 	}
 
-	return f.decoder
+	return f.decoder, false
 }
 
 func (f *field) getFieldPathForName(fp *fieldPath, name string) bool {

pkg/demoinfocs/sendtables2/field_state.go

@@ -34,10 +34,16 @@ func (s *fieldState) set(fp *fieldPath, v interface{}) {
 	z := 0
 	for i := 0; i <= fp.last; i++ {
 		z = fp.path[i]
-		if y := len(x.state); y < z+2 {
-			z := make([]interface{}, max(z+2, y*2))
-			copy(z, x.state)
-			x.state = z
+		if y := len(x.state); y <= z {
+			newCap := max(z+2, y*2)
+			if newCap > cap(x.state) {
+				newSlice := make([]interface{}, z+1, newCap)
+				copy(newSlice, x.state)
+				x.state = newSlice
+			} else {
+				// Re-slice to update the length without allocating new memory
+				x.state = x.state[:z+1]
+			}
 		}
 		if i == fp.last {
 			if _, ok := x.state[z].(*fieldState); !ok {
@@ -56,5 +62,14 @@ func max(a, b int) int {
 	if a > b {
 		return a
 	}
+
+	return b
+}
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+
 	return b
 }

pkg/demoinfocs/sendtables2/serializer.go

@@ -45,6 +45,18 @@ func (s *serializer) getDecoderForFieldPath(fp *fieldPath, pos int) fieldDecoder
 	if len(s.fields) <= index {
 		_panicf("serializer %s: field path %s has no field (%d)", s.name, fp, index)
 	}
+
+	dec, _ := s.fields[index].getDecoderForFieldPath(fp, pos+1)
+
+	return dec
+}
+
+func (s *serializer) getDecoderForFieldPath2(fp *fieldPath, pos int) (fieldDecoder, bool) {
+	index := fp.path[pos]
+	if len(s.fields) <= index {
+		_panicf("serializer %s: field path %s has no field (%d)", s.name, fp, index)
+	}
+
 	return s.fields[index].getDecoderForFieldPath(fp, pos+1)
 }