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-rw-r--r--pkg/state/wire/BUILD12
-rw-r--r--pkg/state/wire/wire.go970
2 files changed, 982 insertions, 0 deletions
diff --git a/pkg/state/wire/BUILD b/pkg/state/wire/BUILD
new file mode 100644
index 000000000..311b93dcb
--- /dev/null
+++ b/pkg/state/wire/BUILD
@@ -0,0 +1,12 @@
+load("//tools:defs.bzl", "go_library")
+
+package(licenses = ["notice"])
+
+go_library(
+ name = "wire",
+ srcs = ["wire.go"],
+ marshal = False,
+ stateify = False,
+ visibility = ["//:sandbox"],
+ deps = ["//pkg/gohacks"],
+)
diff --git a/pkg/state/wire/wire.go b/pkg/state/wire/wire.go
new file mode 100644
index 000000000..93dee6740
--- /dev/null
+++ b/pkg/state/wire/wire.go
@@ -0,0 +1,970 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package wire contains a few basic types that can be composed to serialize
+// graph information for the state package. This package defines the wire
+// protocol.
+//
+// Note that these types are careful about how they implement the relevant
+// interfaces (either value receiver or pointer receiver), so that native-sized
+// types, such as integers and simple pointers, can fit inside the interface
+// object.
+//
+// This package also uses panic as control flow, so called should be careful to
+// wrap calls in appropriate handlers.
+//
+// Testing for this package is driven by the state test package.
+package wire
+
+import (
+ "fmt"
+ "io"
+ "math"
+
+ "gvisor.dev/gvisor/pkg/gohacks"
+)
+
+// Reader is the required reader interface.
+type Reader interface {
+ io.Reader
+ ReadByte() (byte, error)
+}
+
+// Writer is the required writer interface.
+type Writer interface {
+ io.Writer
+ WriteByte(byte) error
+}
+
+// readFull is a utility. The equivalent is not needed for Write, but the API
+// contract dictates that it must always complete all bytes given or return an
+// error.
+func readFull(r io.Reader, p []byte) {
+ for done := 0; done < len(p); {
+ n, err := r.Read(p[done:])
+ done += n
+ if n == 0 && err != nil {
+ panic(err)
+ }
+ }
+}
+
+// Object is a generic object.
+type Object interface {
+ // save saves the given object.
+ //
+ // Panic is used for error control flow.
+ save(Writer)
+
+ // load loads a new object of the given type.
+ //
+ // Panic is used for error control flow.
+ load(Reader) Object
+}
+
+// Bool is a boolean.
+type Bool bool
+
+// loadBool loads an object of type Bool.
+func loadBool(r Reader) Bool {
+ b := loadUint(r)
+ return Bool(b == 1)
+}
+
+// save implements Object.save.
+func (b Bool) save(w Writer) {
+ var v Uint
+ if b {
+ v = 1
+ } else {
+ v = 0
+ }
+ v.save(w)
+}
+
+// load implements Object.load.
+func (Bool) load(r Reader) Object { return loadBool(r) }
+
+// Int is a signed integer.
+//
+// This uses varint encoding.
+type Int int64
+
+// loadInt loads an object of type Int.
+func loadInt(r Reader) Int {
+ u := loadUint(r)
+ x := Int(u >> 1)
+ if u&1 != 0 {
+ x = ^x
+ }
+ return x
+}
+
+// save implements Object.save.
+func (i Int) save(w Writer) {
+ u := Uint(i) << 1
+ if i < 0 {
+ u = ^u
+ }
+ u.save(w)
+}
+
+// load implements Object.load.
+func (Int) load(r Reader) Object { return loadInt(r) }
+
+// Uint is an unsigned integer.
+type Uint uint64
+
+// loadUint loads an object of type Uint.
+func loadUint(r Reader) Uint {
+ var (
+ u Uint
+ s uint
+ )
+ for i := 0; i <= 9; i++ {
+ b, err := r.ReadByte()
+ if err != nil {
+ panic(err)
+ }
+ if b < 0x80 {
+ if i == 9 && b > 1 {
+ panic("overflow")
+ }
+ u |= Uint(b) << s
+ return u
+ }
+ u |= Uint(b&0x7f) << s
+ s += 7
+ }
+ panic("unreachable")
+}
+
+// save implements Object.save.
+func (u Uint) save(w Writer) {
+ for u >= 0x80 {
+ if err := w.WriteByte(byte(u) | 0x80); err != nil {
+ panic(err)
+ }
+ u >>= 7
+ }
+ if err := w.WriteByte(byte(u)); err != nil {
+ panic(err)
+ }
+}
+
+// load implements Object.load.
+func (Uint) load(r Reader) Object { return loadUint(r) }
+
+// Float32 is a 32-bit floating point number.
+type Float32 float32
+
+// loadFloat32 loads an object of type Float32.
+func loadFloat32(r Reader) Float32 {
+ n := loadUint(r)
+ return Float32(math.Float32frombits(uint32(n)))
+}
+
+// save implements Object.save.
+func (f Float32) save(w Writer) {
+ n := Uint(math.Float32bits(float32(f)))
+ n.save(w)
+}
+
+// load implements Object.load.
+func (Float32) load(r Reader) Object { return loadFloat32(r) }
+
+// Float64 is a 64-bit floating point number.
+type Float64 float64
+
+// loadFloat64 loads an object of type Float64.
+func loadFloat64(r Reader) Float64 {
+ n := loadUint(r)
+ return Float64(math.Float64frombits(uint64(n)))
+}
+
+// save implements Object.save.
+func (f Float64) save(w Writer) {
+ n := Uint(math.Float64bits(float64(f)))
+ n.save(w)
+}
+
+// load implements Object.load.
+func (Float64) load(r Reader) Object { return loadFloat64(r) }
+
+// Complex64 is a 64-bit complex number.
+type Complex64 complex128
+
+// loadComplex64 loads an object of type Complex64.
+func loadComplex64(r Reader) Complex64 {
+ re := loadFloat32(r)
+ im := loadFloat32(r)
+ return Complex64(complex(float32(re), float32(im)))
+}
+
+// save implements Object.save.
+func (c *Complex64) save(w Writer) {
+ re := Float32(real(*c))
+ im := Float32(imag(*c))
+ re.save(w)
+ im.save(w)
+}
+
+// load implements Object.load.
+func (*Complex64) load(r Reader) Object {
+ c := loadComplex64(r)
+ return &c
+}
+
+// Complex128 is a 128-bit complex number.
+type Complex128 complex128
+
+// loadComplex128 loads an object of type Complex128.
+func loadComplex128(r Reader) Complex128 {
+ re := loadFloat64(r)
+ im := loadFloat64(r)
+ return Complex128(complex(float64(re), float64(im)))
+}
+
+// save implements Object.save.
+func (c *Complex128) save(w Writer) {
+ re := Float64(real(*c))
+ im := Float64(imag(*c))
+ re.save(w)
+ im.save(w)
+}
+
+// load implements Object.load.
+func (*Complex128) load(r Reader) Object {
+ c := loadComplex128(r)
+ return &c
+}
+
+// String is a string.
+type String string
+
+// loadString loads an object of type String.
+func loadString(r Reader) String {
+ l := loadUint(r)
+ p := make([]byte, l)
+ readFull(r, p)
+ return String(gohacks.StringFromImmutableBytes(p))
+}
+
+// save implements Object.save.
+func (s *String) save(w Writer) {
+ l := Uint(len(*s))
+ l.save(w)
+ p := gohacks.ImmutableBytesFromString(string(*s))
+ _, err := w.Write(p) // Must write all bytes.
+ if err != nil {
+ panic(err)
+ }
+}
+
+// load implements Object.load.
+func (*String) load(r Reader) Object {
+ s := loadString(r)
+ return &s
+}
+
+// Dot is a kind of reference: one of Index and FieldName.
+type Dot interface {
+ isDot()
+}
+
+// Index is a reference resolution.
+type Index uint32
+
+func (Index) isDot() {}
+
+// FieldName is a reference resolution.
+type FieldName string
+
+func (*FieldName) isDot() {}
+
+// Ref is a reference to an object.
+type Ref struct {
+ // Root is the root object.
+ Root Uint
+
+ // Dots is the set of traversals required from the Root object above.
+ // Note that this will be stored in reverse order for efficiency.
+ Dots []Dot
+
+ // Type is the base type for the root object. This is non-nil iff Dots
+ // is non-zero length (that is, this is a complex reference). This is
+ // not *strictly* necessary, but can be used to simplify decoding.
+ Type TypeSpec
+}
+
+// loadRef loads an object of type Ref (abstract).
+func loadRef(r Reader) Ref {
+ ref := Ref{
+ Root: loadUint(r),
+ }
+ l := loadUint(r)
+ ref.Dots = make([]Dot, l)
+ for i := 0; i < int(l); i++ {
+ // Disambiguate between an Index (non-negative) and a field
+ // name (negative). This does some space and avoids a dedicate
+ // loadDot function. See Ref.save for the other side.
+ d := loadInt(r)
+ if d >= 0 {
+ ref.Dots[i] = Index(d)
+ continue
+ }
+ p := make([]byte, -d)
+ readFull(r, p)
+ fieldName := FieldName(gohacks.StringFromImmutableBytes(p))
+ ref.Dots[i] = &fieldName
+ }
+ if l != 0 {
+ // Only if dots is non-zero.
+ ref.Type = loadTypeSpec(r)
+ }
+ return ref
+}
+
+// save implements Object.save.
+func (r *Ref) save(w Writer) {
+ r.Root.save(w)
+ l := Uint(len(r.Dots))
+ l.save(w)
+ for _, d := range r.Dots {
+ // See LoadRef. We use non-negative numbers to encode Index
+ // objects and negative numbers to encode field lengths.
+ switch x := d.(type) {
+ case Index:
+ i := Int(x)
+ i.save(w)
+ case *FieldName:
+ d := Int(-len(*x))
+ d.save(w)
+ p := gohacks.ImmutableBytesFromString(string(*x))
+ if _, err := w.Write(p); err != nil {
+ panic(err)
+ }
+ default:
+ panic("unknown dot implementation")
+ }
+ }
+ if l != 0 {
+ // See above.
+ saveTypeSpec(w, r.Type)
+ }
+}
+
+// load implements Object.load.
+func (*Ref) load(r Reader) Object {
+ ref := loadRef(r)
+ return &ref
+}
+
+// Nil is a primitive zero value of any type.
+type Nil struct{}
+
+// loadNil loads an object of type Nil.
+func loadNil(r Reader) Nil {
+ return Nil{}
+}
+
+// save implements Object.save.
+func (Nil) save(w Writer) {}
+
+// load implements Object.load.
+func (Nil) load(r Reader) Object { return loadNil(r) }
+
+// Slice is a slice value.
+type Slice struct {
+ Length Uint
+ Capacity Uint
+ Ref Ref
+}
+
+// loadSlice loads an object of type Slice.
+func loadSlice(r Reader) Slice {
+ return Slice{
+ Length: loadUint(r),
+ Capacity: loadUint(r),
+ Ref: loadRef(r),
+ }
+}
+
+// save implements Object.save.
+func (s *Slice) save(w Writer) {
+ s.Length.save(w)
+ s.Capacity.save(w)
+ s.Ref.save(w)
+}
+
+// load implements Object.load.
+func (*Slice) load(r Reader) Object {
+ s := loadSlice(r)
+ return &s
+}
+
+// Array is an array value.
+type Array struct {
+ Contents []Object
+}
+
+// loadArray loads an object of type Array.
+func loadArray(r Reader) Array {
+ l := loadUint(r)
+ if l == 0 {
+ // Note that there isn't a single object available to encode
+ // the type of, so we need this additional branch.
+ return Array{}
+ }
+ // All the objects here have the same type, so use dynamic dispatch
+ // only once. All other objects will automatically take the same type
+ // as the first object.
+ contents := make([]Object, l)
+ v := Load(r)
+ contents[0] = v
+ for i := 1; i < int(l); i++ {
+ contents[i] = v.load(r)
+ }
+ return Array{
+ Contents: contents,
+ }
+}
+
+// save implements Object.save.
+func (a *Array) save(w Writer) {
+ l := Uint(len(a.Contents))
+ l.save(w)
+ if l == 0 {
+ // See LoadArray.
+ return
+ }
+ // See above.
+ Save(w, a.Contents[0])
+ for i := 1; i < int(l); i++ {
+ a.Contents[i].save(w)
+ }
+}
+
+// load implements Object.load.
+func (*Array) load(r Reader) Object {
+ a := loadArray(r)
+ return &a
+}
+
+// Map is a map value.
+type Map struct {
+ Keys []Object
+ Values []Object
+}
+
+// loadMap loads an object of type Map.
+func loadMap(r Reader) Map {
+ l := loadUint(r)
+ if l == 0 {
+ // See LoadArray.
+ return Map{}
+ }
+ // See type dispatch notes in Array.
+ keys := make([]Object, l)
+ values := make([]Object, l)
+ k := Load(r)
+ v := Load(r)
+ keys[0] = k
+ values[0] = v
+ for i := 1; i < int(l); i++ {
+ keys[i] = k.load(r)
+ values[i] = v.load(r)
+ }
+ return Map{
+ Keys: keys,
+ Values: values,
+ }
+}
+
+// save implements Object.save.
+func (m *Map) save(w Writer) {
+ l := Uint(len(m.Keys))
+ if int(l) != len(m.Values) {
+ panic(fmt.Sprintf("mismatched keys (%d) Aand values (%d)", len(m.Keys), len(m.Values)))
+ }
+ l.save(w)
+ if l == 0 {
+ // See LoadArray.
+ return
+ }
+ // See above.
+ Save(w, m.Keys[0])
+ Save(w, m.Values[0])
+ for i := 1; i < int(l); i++ {
+ m.Keys[i].save(w)
+ m.Values[i].save(w)
+ }
+}
+
+// load implements Object.load.
+func (*Map) load(r Reader) Object {
+ m := loadMap(r)
+ return &m
+}
+
+// TypeSpec is a type dereference.
+type TypeSpec interface {
+ isTypeSpec()
+}
+
+// TypeID is a concrete type ID.
+type TypeID Uint
+
+func (TypeID) isTypeSpec() {}
+
+// TypeSpecPointer is a pointer type.
+type TypeSpecPointer struct {
+ Type TypeSpec
+}
+
+func (*TypeSpecPointer) isTypeSpec() {}
+
+// TypeSpecArray is an array type.
+type TypeSpecArray struct {
+ Count Uint
+ Type TypeSpec
+}
+
+func (*TypeSpecArray) isTypeSpec() {}
+
+// TypeSpecSlice is a slice type.
+type TypeSpecSlice struct {
+ Type TypeSpec
+}
+
+func (*TypeSpecSlice) isTypeSpec() {}
+
+// TypeSpecMap is a map type.
+type TypeSpecMap struct {
+ Key TypeSpec
+ Value TypeSpec
+}
+
+func (*TypeSpecMap) isTypeSpec() {}
+
+// TypeSpecNil is an empty type.
+type TypeSpecNil struct{}
+
+func (TypeSpecNil) isTypeSpec() {}
+
+// TypeSpec types.
+//
+// These use a distinct encoding on the wire, as they are used only in the
+// interface object. They are decoded through the dedicated loadTypeSpec and
+// saveTypeSpec functions.
+const (
+ typeSpecTypeID Uint = iota
+ typeSpecPointer
+ typeSpecArray
+ typeSpecSlice
+ typeSpecMap
+ typeSpecNil
+)
+
+// loadTypeSpec loads TypeSpec values.
+func loadTypeSpec(r Reader) TypeSpec {
+ switch hdr := loadUint(r); hdr {
+ case typeSpecTypeID:
+ return TypeID(loadUint(r))
+ case typeSpecPointer:
+ return &TypeSpecPointer{
+ Type: loadTypeSpec(r),
+ }
+ case typeSpecArray:
+ return &TypeSpecArray{
+ Count: loadUint(r),
+ Type: loadTypeSpec(r),
+ }
+ case typeSpecSlice:
+ return &TypeSpecSlice{
+ Type: loadTypeSpec(r),
+ }
+ case typeSpecMap:
+ return &TypeSpecMap{
+ Key: loadTypeSpec(r),
+ Value: loadTypeSpec(r),
+ }
+ case typeSpecNil:
+ return TypeSpecNil{}
+ default:
+ // This is not a valid stream?
+ panic(fmt.Errorf("unknown header: %d", hdr))
+ }
+}
+
+// saveTypeSpec saves TypeSpec values.
+func saveTypeSpec(w Writer, t TypeSpec) {
+ switch x := t.(type) {
+ case TypeID:
+ typeSpecTypeID.save(w)
+ Uint(x).save(w)
+ case *TypeSpecPointer:
+ typeSpecPointer.save(w)
+ saveTypeSpec(w, x.Type)
+ case *TypeSpecArray:
+ typeSpecArray.save(w)
+ x.Count.save(w)
+ saveTypeSpec(w, x.Type)
+ case *TypeSpecSlice:
+ typeSpecSlice.save(w)
+ saveTypeSpec(w, x.Type)
+ case *TypeSpecMap:
+ typeSpecMap.save(w)
+ saveTypeSpec(w, x.Key)
+ saveTypeSpec(w, x.Value)
+ case TypeSpecNil:
+ typeSpecNil.save(w)
+ default:
+ // This should not happen?
+ panic(fmt.Errorf("unknown type %T", t))
+ }
+}
+
+// Interface is an interface value.
+type Interface struct {
+ Type TypeSpec
+ Value Object
+}
+
+// loadInterface loads an object of type Interface.
+func loadInterface(r Reader) Interface {
+ return Interface{
+ Type: loadTypeSpec(r),
+ Value: Load(r),
+ }
+}
+
+// save implements Object.save.
+func (i *Interface) save(w Writer) {
+ saveTypeSpec(w, i.Type)
+ Save(w, i.Value)
+}
+
+// load implements Object.load.
+func (*Interface) load(r Reader) Object {
+ i := loadInterface(r)
+ return &i
+}
+
+// Type is type information.
+type Type struct {
+ Name string
+ Fields []string
+}
+
+// loadType loads an object of type Type.
+func loadType(r Reader) Type {
+ name := string(loadString(r))
+ l := loadUint(r)
+ fields := make([]string, l)
+ for i := 0; i < int(l); i++ {
+ fields[i] = string(loadString(r))
+ }
+ return Type{
+ Name: name,
+ Fields: fields,
+ }
+}
+
+// save implements Object.save.
+func (t *Type) save(w Writer) {
+ s := String(t.Name)
+ s.save(w)
+ l := Uint(len(t.Fields))
+ l.save(w)
+ for i := 0; i < int(l); i++ {
+ s := String(t.Fields[i])
+ s.save(w)
+ }
+}
+
+// load implements Object.load.
+func (*Type) load(r Reader) Object {
+ t := loadType(r)
+ return &t
+}
+
+// multipleObjects is a special type for serializing multiple objects.
+type multipleObjects []Object
+
+// loadMultipleObjects loads a series of objects.
+func loadMultipleObjects(r Reader) multipleObjects {
+ l := loadUint(r)
+ m := make(multipleObjects, l)
+ for i := 0; i < int(l); i++ {
+ m[i] = Load(r)
+ }
+ return m
+}
+
+// save implements Object.save.
+func (m *multipleObjects) save(w Writer) {
+ l := Uint(len(*m))
+ l.save(w)
+ for i := 0; i < int(l); i++ {
+ Save(w, (*m)[i])
+ }
+}
+
+// load implements Object.load.
+func (*multipleObjects) load(r Reader) Object {
+ m := loadMultipleObjects(r)
+ return &m
+}
+
+// noObjects represents no objects.
+type noObjects struct{}
+
+// loadNoObjects loads a sentinel.
+func loadNoObjects(r Reader) noObjects { return noObjects{} }
+
+// save implements Object.save.
+func (noObjects) save(w Writer) {}
+
+// load implements Object.load.
+func (noObjects) load(r Reader) Object { return loadNoObjects(r) }
+
+// Struct is a basic composite value.
+type Struct struct {
+ TypeID TypeID
+ fields Object // Optionally noObjects or *multipleObjects.
+}
+
+// Field returns a pointer to the given field slot.
+//
+// This must be called after Alloc.
+func (s *Struct) Field(i int) *Object {
+ if fields, ok := s.fields.(*multipleObjects); ok {
+ return &((*fields)[i])
+ }
+ if _, ok := s.fields.(noObjects); ok {
+ // Alloc may be optionally called; can't call twice.
+ panic("Field called inappropriately, wrong Alloc?")
+ }
+ return &s.fields
+}
+
+// Alloc allocates the given number of fields.
+//
+// This must be called before Add and Save.
+//
+// Precondition: slots must be positive.
+func (s *Struct) Alloc(slots int) {
+ switch {
+ case slots == 0:
+ s.fields = noObjects{}
+ case slots == 1:
+ // Leave it alone.
+ case slots > 1:
+ fields := make(multipleObjects, slots)
+ s.fields = &fields
+ default:
+ // Violates precondition.
+ panic(fmt.Sprintf("Alloc called with negative slots %d?", slots))
+ }
+}
+
+// Fields returns the number of fields.
+func (s *Struct) Fields() int {
+ switch x := s.fields.(type) {
+ case *multipleObjects:
+ return len(*x)
+ case noObjects:
+ return 0
+ default:
+ return 1
+ }
+}
+
+// loadStruct loads an object of type Struct.
+func loadStruct(r Reader) Struct {
+ return Struct{
+ TypeID: TypeID(loadUint(r)),
+ fields: Load(r),
+ }
+}
+
+// save implements Object.save.
+//
+// Precondition: Alloc must have been called, and the fields all filled in
+// appropriately. See Alloc and Add for more details.
+func (s *Struct) save(w Writer) {
+ Uint(s.TypeID).save(w)
+ Save(w, s.fields)
+}
+
+// load implements Object.load.
+func (*Struct) load(r Reader) Object {
+ s := loadStruct(r)
+ return &s
+}
+
+// Object types.
+//
+// N.B. Be careful about changing the order or introducing new elements in the
+// middle here. This is part of the wire format and shouldn't change.
+const (
+ typeBool Uint = iota
+ typeInt
+ typeUint
+ typeFloat32
+ typeFloat64
+ typeNil
+ typeRef
+ typeString
+ typeSlice
+ typeArray
+ typeMap
+ typeStruct
+ typeNoObjects
+ typeMultipleObjects
+ typeInterface
+ typeComplex64
+ typeComplex128
+ typeType
+)
+
+// Save saves the given object.
+//
+// +checkescape all
+//
+// N.B. This function will panic on error.
+func Save(w Writer, obj Object) {
+ switch x := obj.(type) {
+ case Bool:
+ typeBool.save(w)
+ x.save(w)
+ case Int:
+ typeInt.save(w)
+ x.save(w)
+ case Uint:
+ typeUint.save(w)
+ x.save(w)
+ case Float32:
+ typeFloat32.save(w)
+ x.save(w)
+ case Float64:
+ typeFloat64.save(w)
+ x.save(w)
+ case Nil:
+ typeNil.save(w)
+ x.save(w)
+ case *Ref:
+ typeRef.save(w)
+ x.save(w)
+ case *String:
+ typeString.save(w)
+ x.save(w)
+ case *Slice:
+ typeSlice.save(w)
+ x.save(w)
+ case *Array:
+ typeArray.save(w)
+ x.save(w)
+ case *Map:
+ typeMap.save(w)
+ x.save(w)
+ case *Struct:
+ typeStruct.save(w)
+ x.save(w)
+ case noObjects:
+ typeNoObjects.save(w)
+ x.save(w)
+ case *multipleObjects:
+ typeMultipleObjects.save(w)
+ x.save(w)
+ case *Interface:
+ typeInterface.save(w)
+ x.save(w)
+ case *Type:
+ typeType.save(w)
+ x.save(w)
+ case *Complex64:
+ typeComplex64.save(w)
+ x.save(w)
+ case *Complex128:
+ typeComplex128.save(w)
+ x.save(w)
+ default:
+ panic(fmt.Errorf("unknown type: %#v", obj))
+ }
+}
+
+// Load loads a new object.
+//
+// +checkescape all
+//
+// N.B. This function will panic on error.
+func Load(r Reader) Object {
+ switch hdr := loadUint(r); hdr {
+ case typeBool:
+ return loadBool(r)
+ case typeInt:
+ return loadInt(r)
+ case typeUint:
+ return loadUint(r)
+ case typeFloat32:
+ return loadFloat32(r)
+ case typeFloat64:
+ return loadFloat64(r)
+ case typeNil:
+ return loadNil(r)
+ case typeRef:
+ return ((*Ref)(nil)).load(r) // Escapes.
+ case typeString:
+ return ((*String)(nil)).load(r) // Escapes.
+ case typeSlice:
+ return ((*Slice)(nil)).load(r) // Escapes.
+ case typeArray:
+ return ((*Array)(nil)).load(r) // Escapes.
+ case typeMap:
+ return ((*Map)(nil)).load(r) // Escapes.
+ case typeStruct:
+ return ((*Struct)(nil)).load(r) // Escapes.
+ case typeNoObjects: // Special for struct.
+ return loadNoObjects(r)
+ case typeMultipleObjects: // Special for struct.
+ return ((*multipleObjects)(nil)).load(r) // Escapes.
+ case typeInterface:
+ return ((*Interface)(nil)).load(r) // Escapes.
+ case typeComplex64:
+ return ((*Complex64)(nil)).load(r) // Escapes.
+ case typeComplex128:
+ return ((*Complex128)(nil)).load(r) // Escapes.
+ case typeType:
+ return ((*Type)(nil)).load(r) // Escapes.
+ default:
+ // This is not a valid stream?
+ panic(fmt.Errorf("unknown header: %d", hdr))
+ }
+}
+
+// LoadUint loads a single unsigned integer.
+//
+// N.B. This function will panic on error.
+func LoadUint(r Reader) uint64 {
+ return uint64(loadUint(r))
+}
+
+// SaveUint saves a single unsigned integer.
+//
+// N.B. This function will panic on error.
+func SaveUint(w Writer, v uint64) {
+ Uint(v).save(w)
+}