diff options
Diffstat (limited to 'tools/go_marshal')
-rw-r--r-- | tools/go_marshal/README.md | 8 | ||||
-rw-r--r-- | tools/go_marshal/primitive/primitive.go | 72 |
2 files changed, 75 insertions, 5 deletions
diff --git a/tools/go_marshal/README.md b/tools/go_marshal/README.md index 4886efddf..68d759083 100644 --- a/tools/go_marshal/README.md +++ b/tools/go_marshal/README.md @@ -9,11 +9,9 @@ automatically generating code to marshal go data structures to memory. `binary.Marshal` by moving the go runtime reflection necessary to marshal a struct to compile-time. -`go_marshal` automatically generates implementations for `abi.Marshallable` and -`safemem.{Reader,Writer}`. Call-sites for serialization (typically syscall -implementations) can directly invoke `safemem.Reader.ReadToBlocks` and -`safemem.Writer.WriteFromBlocks`. Data structures that require custom -serialization will have manual implementations for these interfaces. +`go_marshal` automatically generates implementations for `marshal.Marshallable` +and `safemem.{Reader,Writer}`. Data structures that require custom serialization +will have manual implementations for these interfaces. Data structures can be flagged for code generation by adding a struct-level comment `// +marshal`. diff --git a/tools/go_marshal/primitive/primitive.go b/tools/go_marshal/primitive/primitive.go index ebcf130ae..d93edda8b 100644 --- a/tools/go_marshal/primitive/primitive.go +++ b/tools/go_marshal/primitive/primitive.go @@ -17,10 +17,22 @@ package primitive import ( + "io" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/tools/go_marshal/marshal" ) +// 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 @@ -51,6 +63,66 @@ type Int64 int64 // +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(task marshal.Task, addr usermem.Addr) (int, error) { + return task.CopyInBytes(addr, *b) +} + +// CopyOut implements marshal.Marshallable.CopyOut. +func (b *ByteSlice) CopyOut(task marshal.Task, addr usermem.Addr) (int, error) { + return task.CopyOutBytes(addr, *b) +} + +// CopyOutN implements marshal.Marshallable.CopyOutN. +func (b *ByteSlice) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) { + return task.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. |