1 files changed, 349 insertions, 0 deletions
diff --git a/pkg/marshal/primitive/primitive.go b/pkg/marshal/primitive/primitive.go
new file mode 100644
index 000000000..4b342de6b
--- /dev/null
+++ b/pkg/marshal/primitive/primitive.go
@@ -0,0 +1,349 @@
+// 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 primitive defines marshal.Marshallable implementations for primitive
+// types.
+package primitive
+
+import (
+	"io"
+
+	"gvisor.dev/gvisor/pkg/context"
+	"gvisor.dev/gvisor/pkg/marshal"
+	"gvisor.dev/gvisor/pkg/usermem"
+)
+
+// Int8 is a marshal.Marshallable implementation for int8.
+//
+// +marshal slice:Int8Slice:inner
+type Int8 int8
+
+// Uint8 is a marshal.Marshallable implementation for uint8.
+//
+// +marshal slice:Uint8Slice:inner
+type Uint8 uint8
+
+// Int16 is a marshal.Marshallable implementation for int16.
+//
+// +marshal slice:Int16Slice:inner
+type Int16 int16
+
+// Uint16 is a marshal.Marshallable implementation for uint16.
+//
+// +marshal slice:Uint16Slice:inner
+type Uint16 uint16
+
+// Int32 is a marshal.Marshallable implementation for int32.
+//
+// +marshal slice:Int32Slice:inner
+type Int32 int32
+
+// Uint32 is a marshal.Marshallable implementation for uint32.
+//
+// +marshal slice:Uint32Slice:inner
+type Uint32 uint32
+
+// Int64 is a marshal.Marshallable implementation for int64.
+//
+// +marshal slice:Int64Slice:inner
+type Int64 int64
+
+// Uint64 is a marshal.Marshallable implementation for uint64.
+//
+// +marshal slice:Uint64Slice:inner
+type Uint64 uint64
+
+// ByteSlice is a marshal.Marshallable implementation for []byte.
+// This is a convenience wrapper around a dynamically sized type, and can't be
+// embedded in other marshallable types because it breaks assumptions made by
+// go-marshal internals. It violates the "no dynamically-sized types"
+// constraint of the go-marshal library.
+type ByteSlice []byte
+
+// SizeBytes implements marshal.Marshallable.SizeBytes.
+func (b *ByteSlice) SizeBytes() int {
+	return len(*b)
+}
+
+// MarshalBytes implements marshal.Marshallable.MarshalBytes.
+func (b *ByteSlice) MarshalBytes(dst []byte) {
+	copy(dst, *b)
+}
+
+// UnmarshalBytes implements marshal.Marshallable.UnmarshalBytes.
+func (b *ByteSlice) UnmarshalBytes(src []byte) {
+	copy(*b, src)
+}
+
+// Packed implements marshal.Marshallable.Packed.
+func (b *ByteSlice) Packed() bool {
+	return false
+}
+
+// MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
+func (b *ByteSlice) MarshalUnsafe(dst []byte) {
+	b.MarshalBytes(dst)
+}
+
+// UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
+func (b *ByteSlice) UnmarshalUnsafe(src []byte) {
+	b.UnmarshalBytes(src)
+}
+
+// CopyIn implements marshal.Marshallable.CopyIn.
+func (b *ByteSlice) CopyIn(cc marshal.CopyContext, addr usermem.Addr) (int, error) {
+	return cc.CopyInBytes(addr, *b)
+}
+
+// CopyOut implements marshal.Marshallable.CopyOut.
+func (b *ByteSlice) CopyOut(cc marshal.CopyContext, addr usermem.Addr) (int, error) {
+	return cc.CopyOutBytes(addr, *b)
+}
+
+// CopyOutN implements marshal.Marshallable.CopyOutN.
+func (b *ByteSlice) CopyOutN(cc marshal.CopyContext, addr usermem.Addr, limit int) (int, error) {
+	return cc.CopyOutBytes(addr, (*b)[:limit])
+}
+
+// WriteTo implements io.WriterTo.WriteTo.
+func (b *ByteSlice) WriteTo(w io.Writer) (int64, error) {
+	n, err := w.Write(*b)
+	return int64(n), err
+}
+
+var _ marshal.Marshallable = (*ByteSlice)(nil)
+
+// Below, we define some convenience functions for marshalling primitive types
+// using the newtypes above, without requiring superfluous casts.
+
+// 8-bit integers
+
+// CopyInt8In is a convenient wrapper for copying in an int8 from the task's
+// memory.
+func CopyInt8In(cc marshal.CopyContext, addr usermem.Addr, dst *int8) (int, error) {
+	var buf Int8
+	n, err := buf.CopyIn(cc, addr)
+	if err != nil {
+		return n, err
+	}
+	*dst = int8(buf)
+	return n, nil
+}
+
+// CopyInt8Out is a convenient wrapper for copying out an int8 to the task's
+// memory.
+func CopyInt8Out(cc marshal.CopyContext, addr usermem.Addr, src int8) (int, error) {
+	srcP := Int8(src)
+	return srcP.CopyOut(cc, addr)
+}
+
+// CopyUint8In is a convenient wrapper for copying in a uint8 from the task's
+// memory.
+func CopyUint8In(cc marshal.CopyContext, addr usermem.Addr, dst *uint8) (int, error) {
+	var buf Uint8
+	n, err := buf.CopyIn(cc, addr)
+	if err != nil {
+		return n, err
+	}
+	*dst = uint8(buf)
+	return n, nil
+}
+
+// CopyUint8Out is a convenient wrapper for copying out a uint8 to the task's
+// memory.
+func CopyUint8Out(cc marshal.CopyContext, addr usermem.Addr, src uint8) (int, error) {
+	srcP := Uint8(src)
+	return srcP.CopyOut(cc, addr)
+}
+
+// 16-bit integers
+
+// CopyInt16In is a convenient wrapper for copying in an int16 from the task's
+// memory.
+func CopyInt16In(cc marshal.CopyContext, addr usermem.Addr, dst *int16) (int, error) {
+	var buf Int16
+	n, err := buf.CopyIn(cc, addr)
+	if err != nil {
+		return n, err
+	}
+	*dst = int16(buf)
+	return n, nil
+}
+
+// CopyInt16Out is a convenient wrapper for copying out an int16 to the task's
+// memory.
+func CopyInt16Out(cc marshal.CopyContext, addr usermem.Addr, src int16) (int, error) {
+	srcP := Int16(src)
+	return srcP.CopyOut(cc, addr)
+}
+
+// CopyUint16In is a convenient wrapper for copying in a uint16 from the task's
+// memory.
+func CopyUint16In(cc marshal.CopyContext, addr usermem.Addr, dst *uint16) (int, error) {
+	var buf Uint16
+	n, err := buf.CopyIn(cc, addr)
+	if err != nil {
+		return n, err
+	}
+	*dst = uint16(buf)
+	return n, nil
+}
+
+// CopyUint16Out is a convenient wrapper for copying out a uint16 to the task's
+// memory.
+func CopyUint16Out(cc marshal.CopyContext, addr usermem.Addr, src uint16) (int, error) {
+	srcP := Uint16(src)
+	return srcP.CopyOut(cc, addr)
+}
+
+// 32-bit integers
+
+// CopyInt32In is a convenient wrapper for copying in an int32 from the task's
+// memory.
+func CopyInt32In(cc marshal.CopyContext, addr usermem.Addr, dst *int32) (int, error) {
+	var buf Int32
+	n, err := buf.CopyIn(cc, addr)
+	if err != nil {
+		return n, err
+	}
+	*dst = int32(buf)
+	return n, nil
+}
+
+// CopyInt32Out is a convenient wrapper for copying out an int32 to the task's
+// memory.
+func CopyInt32Out(cc marshal.CopyContext, addr usermem.Addr, src int32) (int, error) {
+	srcP := Int32(src)
+	return srcP.CopyOut(cc, addr)
+}
+
+// CopyUint32In is a convenient wrapper for copying in a uint32 from the task's
+// memory.
+func CopyUint32In(cc marshal.CopyContext, addr usermem.Addr, dst *uint32) (int, error) {
+	var buf Uint32
+	n, err := buf.CopyIn(cc, addr)
+	if err != nil {
+		return n, err
+	}
+	*dst = uint32(buf)
+	return n, nil
+}
+
+// CopyUint32Out is a convenient wrapper for copying out a uint32 to the task's
+// memory.
+func CopyUint32Out(cc marshal.CopyContext, addr usermem.Addr, src uint32) (int, error) {
+	srcP := Uint32(src)
+	return srcP.CopyOut(cc, addr)
+}
+
+// 64-bit integers
+
+// CopyInt64In is a convenient wrapper for copying in an int64 from the task's
+// memory.
+func CopyInt64In(cc marshal.CopyContext, addr usermem.Addr, dst *int64) (int, error) {
+	var buf Int64
+	n, err := buf.CopyIn(cc, addr)
+	if err != nil {
+		return n, err
+	}
+	*dst = int64(buf)
+	return n, nil
+}
+
+// CopyInt64Out is a convenient wrapper for copying out an int64 to the task's
+// memory.
+func CopyInt64Out(cc marshal.CopyContext, addr usermem.Addr, src int64) (int, error) {
+	srcP := Int64(src)
+	return srcP.CopyOut(cc, addr)
+}
+
+// CopyUint64In is a convenient wrapper for copying in a uint64 from the task's
+// memory.
+func CopyUint64In(cc marshal.CopyContext, addr usermem.Addr, dst *uint64) (int, error) {
+	var buf Uint64
+	n, err := buf.CopyIn(cc, addr)
+	if err != nil {
+		return n, err
+	}
+	*dst = uint64(buf)
+	return n, nil
+}
+
+// CopyUint64Out is a convenient wrapper for copying out a uint64 to the task's
+// memory.
+func CopyUint64Out(cc marshal.CopyContext, addr usermem.Addr, src uint64) (int, error) {
+	srcP := Uint64(src)
+	return srcP.CopyOut(cc, addr)
+}
+
+// CopyByteSliceIn is a convenient wrapper for copying in a []byte from the
+// task's memory.
+func CopyByteSliceIn(cc marshal.CopyContext, addr usermem.Addr, dst *[]byte) (int, error) {
+	var buf ByteSlice
+	n, err := buf.CopyIn(cc, addr)
+	if err != nil {
+		return n, err
+	}
+	*dst = []byte(buf)
+	return n, nil
+}
+
+// CopyByteSliceOut is a convenient wrapper for copying out a []byte to the
+// task's memory.
+func CopyByteSliceOut(cc marshal.CopyContext, addr usermem.Addr, src []byte) (int, error) {
+	srcP := ByteSlice(src)
+	return srcP.CopyOut(cc, addr)
+}
+
+// CopyStringIn is a convenient wrapper for copying in a string from the
+// task's memory.
+func CopyStringIn(cc marshal.CopyContext, addr usermem.Addr, dst *string) (int, error) {
+	var buf ByteSlice
+	n, err := buf.CopyIn(cc, addr)
+	if err != nil {
+		return n, err
+	}
+	*dst = string(buf)
+	return n, nil
+}
+
+// CopyStringOut is a convenient wrapper for copying out a string to the task's
+// memory.
+func CopyStringOut(cc marshal.CopyContext, addr usermem.Addr, src string) (int, error) {
+	srcP := ByteSlice(src)
+	return srcP.CopyOut(cc, addr)
+}
+
+// IOCopyContext wraps an object implementing usermem.IO to implement
+// marshal.CopyContext.
+type IOCopyContext struct {
+	Ctx  context.Context
+	IO   usermem.IO
+	Opts usermem.IOOpts
+}
+
+// CopyScratchBuffer implements marshal.CopyContext.CopyScratchBuffer.
+func (i *IOCopyContext) CopyScratchBuffer(size int) []byte {
+	return make([]byte, size)
+}
+
+// CopyOutBytes implements marshal.CopyContext.CopyOutBytes.
+func (i *IOCopyContext) CopyOutBytes(addr usermem.Addr, b []byte) (int, error) {
+	return i.IO.CopyOut(i.Ctx, addr, b, i.Opts)
+}
+
+// CopyInBytes implements marshal.CopyContext.CopyInBytes.
+func (i *IOCopyContext) CopyInBytes(addr usermem.Addr, b []byte) (int, error) {
+	return i.IO.CopyIn(i.Ctx, addr, b, i.Opts)
+}