lib/vom/wiretype.vdl

package vom

// Built-in type IDs
const (
	// Primitive types.
	WireIDBool       = typeID(1)
	WireIDByte       = typeID(2)
	WireIDString     = typeID(3)
	WireIDUint16     = typeID(4)
	WireIDUint32     = typeID(5)
	WireIDUint64     = typeID(6)
	WireIDInt16      = typeID(7)
	WireIDInt32      = typeID(8)
	WireIDInt64      = typeID(9)
	WireIDFloat32    = typeID(10)
	WireIDFloat64    = typeID(11)
	WireIDComplex64  = typeID(12)
	WireIDComplex128 = typeID(13)
	WireIDTypeObject = typeID(14)
	WireIDAny        = typeID(15)

	// Other commonly used composites.
	WireIDByteList   = typeID(39)
	WireIDStringList = typeID(40)

	// The first user-defined typeID is 41.
	WireIDFirstUserType = typeID(41)
)

// typeID uniquely identifies a type definition within a vom stream.
type typeID uint64

// The wireType union is used to encode the payload part of each type message,
// using the regular rules for encoding union values.  But unlike our regular
// encoding, the type message for wireType itself (and its fields) are never
// encoded; we need to bootstrap the system.  Thus unlike regular values, the
// ordering of fields within the wire* types cannot be changed.
type wireType union {
	// FIELD INDICES MUST NOT BE CHANGED.
	NamedT    wireNamed    // INDEX = 0
	EnumT     wireEnum     // INDEX = 1
	ArrayT    wireArray    // INDEX = 2
	ListT     wireList     // INDEX = 3
	SetT      wireSet      // INDEX = 4
	MapT      wireMap      // INDEX = 5
	StructT   wireStruct   // INDEX = 6
	UnionT    wireUnion    // INDEX = 7
	OptionalT wireOptional // INDEX = 8
}

// wireNamed represents a type definition for named primitives.
type wireNamed struct {
	Name string
	Base typeID
}

// wireEnum represents an type definition for enum types.
type wireEnum struct {
	Name   string
	Labels []string
}

// wireArray represents an type definition for array types.
type wireArray struct {
	Name string
	Elem typeID
	Len  uint64
}

// wireList represents a type definition for list types.
type wireList struct {
	Name string
	Elem typeID
}

// wireSet represents a type definition for set types.
type wireSet struct {
	Name string
	Key  typeID
}

// wireMap represents a type definition for map types.
type wireMap struct {
	Name string
	Key  typeID
	Elem typeID
}

// wireField represents a field in a struct or union type.
type wireField struct {
	Name string
	Type typeID
}

// wireStruct represents a type definition for struct types.
type wireStruct struct {
	Name   string
	Fields []wireField
}

// wireUnion represents a type definition for union types.
type wireUnion struct {
	Name   string
	Fields []wireField
}

// wireOptional represents an type definition for optional types.
type wireOptional struct {
	Name string
	Elem typeID
}

// Control codes used in VOM wire format
//
//   region 1: 0x80...0xBF (64 entries)
//   region 2: 0xC0...0xDF (32 entries)
//   region 3: 0xE0...0xEF (16 entries)
const (
  WireCtrlNil = byte(0xe0)
  WireCtrlEOF = byte(0xe1)
)