decode the fields

ent/array.go

@@ -0,0 +1,17 @@
+package ent
+
+import (
+	"strconv"
+)
+
+type array struct {
+	slots     []interface{}
+	_slotType string
+	decoder
+}
+
+func (a *array) slotName(slot int) string               { return strconv.Itoa(slot) }
+func (a *array) slotValue(slot int) interface{}         { return a.slots[slot] }
+func (a *array) slotType(slot int) string               { return a._slotType }
+func (a *array) slotDecoder(slot int) decoder           { return a.decoder }
+func (a *array) setSlotValue(slot int, val interface{}) { a.slots[slot] = val }

ent/class.go

@@ -19,12 +19,17 @@ type Class struct {
 	fieldNames map[string]int
 }
 
-func (c *Class) New(serial int) *Entity {
-	return &Entity{
-		Class:  c,
-		slots:  make([]interface{}, len(c.Fields)),
-		serial: serial,
+func (c *Class) New(serial int, baseline bool) *Entity {
+	e := &Entity{
+		Class:      c,
+		slots:      make([]interface{}, len(c.Fields)),
+		serial:     serial,
+		isBaseline: baseline,
 	}
+	for slot := range e.slots {
+		e.slots[slot] = c.Fields[slot].initializer()
+	}
+	return e
 }
 
 func (c Class) String() string {

ent/cutl.go

@@ -0,0 +1,20 @@
+package ent
+
+import (
+	"strconv"
+)
+
+type cutlVector struct {
+	slots     []interface{}
+	_slotType string
+	decoder
+}
+
+func (v *cutlVector) slotName(slot int) string       { return strconv.Itoa(slot) }
+func (v *cutlVector) slotValue(slot int) interface{} { return v.slots[slot] }
+func (v *cutlVector) slotType(slot int) string       { return v._slotType }
+func (v *cutlVector) slotDecoder(slot int) decoder   { return v.decoder }
+
+func (v *cutlVector) setSlotValue(slot int, val interface{}) {
+	v.slots[slot] = val
+}

ent/decoders.go

@@ -44,26 +44,27 @@ func newFieldDecoder(n *Namespace, f *Field) decoder {
 
 	// for compound types such as handles, vectors (in the c++ std::vector
 	// sense), and arrays
-	ts := parseTypeName(n, typeName)
-	switch ts.kind {
+	switch f.typeSpec.kind {
 	case t_element:
-		Debug.Printf("weird typespec: we shouldn't have elements here: %v", ts)
+		Debug.Printf("weird typespec: we shouldn't have elements here: %v", f.typeSpec)
 		return func(bit.Reader) interface{} {
-			Info.Fatalf("unable to decode element of type: %v", ts.name)
+			Info.Fatalf("unable to decode element of type: %v", f.typeSpec.name)
 			return nil
 		}
 	case t_object:
 		return func(br bit.Reader) interface{} {
-			Debug.Printf("unable to decode object of type: %v", ts.name)
+			Debug.Printf("unable to decode object of type: %v", f.typeSpec.name)
 			return decodeVarInt32(br)
 		}
 	case t_array:
-		return arrayDecoder(n, f, ts)
+		return arrayDecoder(n, f)
 	case t_template:
-		return templateDecoder(f, ts)
+		return templateDecoder(f)
+	case t_pointer:
+		return decodeBool
 	}
 
-	return nil
+	panic("fart")
 }
 
 func decodeBool(br bit.Reader) interface{}     { return bit.ReadBool(br) }
@@ -85,10 +86,8 @@ func decodeColor(br bit.Reader) interface{} {
 
 func entityDecoder(c *Class) decoder {
 	return func(br bit.Reader) interface{} {
-		if bit.ReadBool(br) {
-			return c.New(-1)
-		}
-		return nil
+		bit.ReadBool(br) // what does this do
+		return c.New(-1, false)
 	}
 }
 
@@ -201,18 +200,28 @@ func qangleDecoder(f *Field) decoder {
 	}
 }
 
-func arrayDecoder(n *Namespace, f *Field, ts typeSpec) decoder {
-	return decodeVarInt32
+func arrayDecoder(n *Namespace, f *Field) decoder {
+	return func(br bit.Reader) interface{} {
+		Debug.Printf("dunno what this int32 val does in array decoder: %d", bit.ReadVarInt32(br))
+		if f.initializer != nil {
+			return f.initializer()
+		}
+		return nil
+	}
 }
 
-func templateDecoder(f *Field, ts typeSpec) decoder {
-	switch ts.template {
+func templateDecoder(f *Field) decoder {
+	switch f.typeSpec.template {
 	case "CHandle":
 		return decodeVarInt32
 	case "CStrongHandle":
 		return decodeVarInt64
 	case "CUtlVector":
-		return decodeVarInt32
+		return func(br bit.Reader) interface{} {
+			v := decodeVarInt32(br)
+			Debug.Printf("dunno what this varint is for in the cutlvector decoder: %v", v)
+			return v
+		}
 	}
 	return nil
 }

ent/dict.go

@@ -72,7 +72,7 @@ func (d *Dict) createEntity(id int) error {
 	if class == nil {
 		return fmt.Errorf("unable to create entity %d: no class found for class name %s, version %d", className, classV)
 	}
-	e := class.New(serial)
+	e := class.New(serial, false)
 	d.entities[id] = e
 	Debug.Printf("create entity id: %d serial: %d classId: %d className: %v class: %v\n", id, serial, classId, className, class)
 	return fillSlots(e, class.Name.String(), d.sr, d.br)
@@ -190,7 +190,7 @@ func (d *Dict) syncBaselines() {
 		}
 
 		if c.baseline == nil {
-			c.baseline = c.New(-1)
+			c.baseline = c.New(-1, true)
 		}
 
 		if e.Value == nil || len(e.Value) == 0 {

ent/entity.go

@@ -2,12 +2,22 @@ package ent
 
 type Entity struct {
 	*Class
-	serial int
-	slots  []interface{}
+	serial     int
+	slots      []interface{}
+	isBaseline bool
 }
 
-func (e *Entity) slotName(n int) string             { return e.Class.Fields[n].name.String() }
-func (e *Entity) slotType(n int) string             { return e.Class.Fields[n]._type.String() }
-func (e *Entity) slotValue(n int) interface{}       { return e.slots[n] }
+func (e *Entity) slotName(n int) string { return e.Class.Fields[n].name.String() }
+func (e *Entity) slotType(n int) string { return e.Class.Fields[n]._type.String() }
+func (e *Entity) slotValue(n int) interface{} {
+	v := e.slots[n]
+	if v != nil {
+		return v
+	}
+	if !e.isBaseline && e.Class.baseline != nil {
+		return e.Class.baseline.slotValue(n)
+	}
+	return nil
+}
 func (e *Entity) slotDecoder(n int) decoder         { return e.Class.Fields[n].decoder }
 func (e *Entity) setSlotValue(n int, v interface{}) { e.slots[n] = v }

ent/field.go

@@ -8,7 +8,8 @@ import (
 )
 
 type Field struct {
-	_type             Symbol  // type of data held by the field
+	_type             Symbol // type of data held by the field
+	typeSpec          typeSpec
 	name              Symbol  // name of the field
 	sendNode          Symbol  // not sure what this is
 	bits              uint    // number of bits used to encode field?
@@ -20,7 +21,8 @@ type Field struct {
 	class             *Class  // source class on which the field was originally defined
 	encoder           *Symbol // binary encoder, named explicitly in protobuf
 	decoder                   // decodes field values from a bit stream
-	isTemplate        bool    // whether or not the field is a template type
+	initializer       func() interface{}
+	isTemplate        bool // whether or not the field is a template type
 	templateType      string
 	elemType          string
 }
@@ -56,6 +58,7 @@ func (f *Field) fromProto(flat *dota.ProtoFlattenedSerializerFieldT, t *SymbolTa
 	f.flags = int(flat.GetEncodeFlags())
 	f.low = flat.GetLowValue()
 	f.high = flat.GetHighValue()
+	f.initializer = nilInitializer
 
 	if flat.FieldSerializerNameSym == nil {
 		f.serializer = nil
@@ -69,3 +72,30 @@ func (f *Field) fromProto(flat *dota.ProtoFlattenedSerializerFieldT, t *SymbolTa
 	f.sendNode = t.Symbol(int(*flat.SendNodeSym))
 	Debug.Printf("new field: %v", f)
 }
+
+// creates a new field which is a sort of virtual field that represents what a
+// field woudl look like if we had one for a container field's elements.
+// honestly this is a really shitty hack it just seems easier than rewriting
+// the newFieldDecoder logic.
+func (f *Field) memberField() *Field {
+	mf := new(Field)
+	*mf = *f
+	mf.typeSpec = *f.typeSpec.member
+	// yeahhhh
+	mf._type = Symbol{0, &SymbolTable{mf.typeSpec.name}}
+	return mf
+}
+
+func (f *Field) isContainer() bool {
+	if f.typeSpec.kind == t_array {
+		return true
+	}
+	if f.typeSpec.kind == t_template {
+		if f.typeSpec.template == "CUtlVector" {
+			return true
+		}
+	}
+	return false
+}
+
+func nilInitializer() interface{} { return nil }

ent/float_decoders.go

@@ -86,7 +86,5 @@ func floatDecoder(f *Field) decoder {
 
 // reads an IEEE 754 binary float value off of the stream
 func ieeeFloat32Decoder(br bit.Reader) interface{} {
-	u := uint32(br.ReadBits(32))
-	Debug.Printf("ieee float32 decode bits: %d", u)
-	return math.Float32frombits(u)
+	return math.Float32frombits(uint32(br.ReadBits(32)))
 }

ent/namespace.go

@@ -107,6 +107,32 @@ func (n *Namespace) mergeSendTables(st *dota.CDemoSendTables) error {
 			}
 		}
 
+		// for some fields, we want to initialize a zero value on the baseline
+		// instance. specifically, we do this for arrays so that we can't try
+		// to index into nil.
+		f.typeSpec = parseTypeName(n, f._type.String())
+		if f.isContainer() {
+			mf := f.memberField()
+			fn := newFieldDecoder(n, mf)
+			if f.typeSpec.kind == t_array {
+				f.initializer = func() interface{} {
+					return &array{
+						slots:     make([]interface{}, f.typeSpec.size),
+						_slotType: mf._type.String(),
+						decoder:   fn,
+					}
+				}
+			} else if f.typeSpec.kind == t_template && f.typeSpec.template == "CUtlVector" {
+				f.initializer = func() interface{} {
+					return &cutlVector{
+						slots:     make([]interface{}, f.typeSpec.size),
+						_slotType: mf._type.String(),
+						decoder:   fn,
+					}
+				}
+			}
+		}
+
 		// we also wait until after we've discovered all of the classes to
 		// build the field decoder functions, because some fields are
 		// themselves entities.

ent/selection.go

@@ -21,22 +21,24 @@ func (s selection) path() []int    { return s.vals[:s.count] }
 
 func (s selection) fill(offset int, displayPath string, dest slotted, br bit.Reader) error {
 	slot := s.vals[offset]
-	switch s.count - offset {
-	case 0:
+	if s.count-offset <= 0 {
 		panic("selection makes no sense")
+	}
+	switch s.count - offset {
 	case 1:
 		fn := dest.slotDecoder(slot)
 		if fn == nil {
-			switch v := dest.(type) {
+			switch dest.(type) {
 			case *Entity:
 				Debug.Printf("%s %s (%s)", s, fmt.Sprintf("%s.%s", displayPath, dest.slotName(slot)), dest.slotType(slot))
-				Info.Fatalf("%v entity has no decoder for slot %d (%v)", v.Class, slot, v.Class.Fields[slot])
+				return nil
+				// Info.Fatalf("%v entity has no decoder for slot %d (%v)", v.Class, slot, v.Class.Fields[slot])
 			default:
-				Info.Fatalf("slotted value %v has no decoder for slot %d", dest, slot)
+				Info.Printf("slotted value %v has no decoder for slot %d", dest, slot)
+				return nil
 			}
 		}
 		old := dest.slotValue(slot)
-		Debug.Printf("%s %s (%s): %v", s, fmt.Sprintf("%s.%s", displayPath, dest.slotName(slot)), dest.slotType(slot), old)
 		val := fn(br)
 		dest.setSlotValue(slot, val)
 		Debug.Printf("%s %s (%s): %v -> %v", s, fmt.Sprintf("%s.%s", displayPath, dest.slotName(slot)), dest.slotType(slot), old, val)
@@ -45,7 +47,7 @@ func (s selection) fill(offset int, displayPath string, dest slotted, br bit.Rea
 		v := dest.slotValue(slot)
 		vs, ok := v.(slotted)
 		if !ok {
-			Info.Fatalf("child selection %s at offset %d refers to a slot (%d: %s) that contains a non-slotted type: %s", s, offset, slot, fmt.Sprintf("%s.%s", displayPath, dest.slotName(slot)), dest.slotType(slot))
+			Info.Printf("child selection %s at offset %d refers to a slot (%d: %s) that contains a non-slotted type: %s with value: %v", s, offset, slot, fmt.Sprintf("%s.%s", displayPath, dest.slotName(slot)), dest.slotType(slot), v)
 			return fmt.Errorf("child selection refers to a slot that doesn't contain a slotted value")
 		}
 		return s.fill(offset+1, fmt.Sprintf("%s.%s", displayPath, dest.slotName(slot)), vs, br)

ent/type_spec.go

@@ -11,6 +11,7 @@ const (
 	t_object          // c++ object type that is not a known element class
 	t_array           // c++ array type
 	t_template        // c++ template type
+	t_pointer         // c++ pointer
 )
 
 // constant identifiers
@@ -40,6 +41,13 @@ func parseTypeName(n *Namespace, s string) typeSpec {
 		return t
 	}
 
+	if strings.HasSuffix(s, "*") {
+		t.kind = t_pointer
+		t.member = new(typeSpec)
+		*t.member = parseTypeName(n, s[:len(s)-2])
+		return t
+	}
+
 	// presumably this is some sort of array type
 	if strings.ContainsRune(s, '[') {
 		memName, count := parseArrayName(s)