adding Bytes() to MaskBit

bitmask/bitmask.go

@@ -0,0 +1,118 @@
+package bitmask
+
+import (
+	"bytes"
+	"errors"
+	"encoding/binary"
+	"math/bits"
+)
+
+// MaskBit is a flag container.
+type MaskBit uint
+
+/*
+	NewMaskBit is a convenience function.
+	It will return a MaskBit with a (referenced) value of 0, so set your consts up accordingly.
+
+	It is highly recommended to set this default as a "None" flag (separate from your iotas!)
+	as shown in the example.
+*/
+func NewMaskBit() (m *MaskBit) {
+
+	m = new(MaskBit)
+
+	return
+}
+
+// NewMaskBitExplicit is like NewMaskBit, but allows you to specify a non-zero (0x0) value.
+func NewMaskBitExplicit(value uint) (m *MaskBit) {
+
+	var v MaskBit = MaskBit(value)
+
+	m = &v
+
+	return
+}
+
+// HasFlag is true if m has MaskBit flag set/enabled.
+func (m *MaskBit) HasFlag(flag MaskBit) (r bool) {
+
+	var b MaskBit = *m
+
+	if b&flag != 0 {
+		r = true
+	}
+	return
+}
+
+// AddFlag adds MaskBit flag to m.
+func (m *MaskBit) AddFlag(flag MaskBit) {
+
+	*m |= flag
+
+	return
+}
+
+// ClearFlag removes MaskBit flag from m.
+func (m *MaskBit) ClearFlag(flag MaskBit) {
+
+	*m &= flag
+
+	return
+}
+
+// ToggleFlag switches MaskBit flag in m to its inverse; if true, it is now false and vice versa.
+func (m *MaskBit) ToggleFlag(flag MaskBit) {
+
+	*m ^= flag
+
+	return
+}
+
+/*
+	Bytes returns the current value of a MasBit as a byte slice (big-endian).
+
+	If trim is false, b will (probably) be 4 bytes long if you're on a 32-bit size system,
+	and b will (probably) be 8 bytes long if you're on a 64-bit size system. You can determine
+	the size of the resulting slice via (math/)bits.UintSize / 8.
+
+	If trim is true, it will trim leading null bytes (if any). This will lead to an unpredictable
+	byte slice length in b, but is most likely preferred for byte operations.
+
+*/
+func (m *MaskBit) Bytes(trim bool) (b []byte) {
+
+	var b2 []byte
+	var size int = bits.UintSize / 8
+	var err error
+
+	b2 = make([]byte, size)
+
+	switch s := bits.UintSize; s {
+	case 32:
+		binary.BigEndian.PutUint32(b2[:], uint32(*m))
+	case 64:
+		binary.BigEndian.PutUint64(b2[:], uint64(*m))
+	default:
+		err = errors.New("unsupported Uint/system bit size")
+		panic(err)
+	}
+
+	if trim {
+		b = bytes.TrimLeft(b2, "\x00")
+		return
+	} else {
+		b = b2
+		return
+	}
+
+	return
+}
+
+// Value returns the current raw uint value of a MaskBit.
+func (m *MaskBit) Value() (v uint) {
+
+	v = uint(*m)
+
+	return
+}

bitmask/bitmasks.go

@@ -1,46 +0,0 @@
-package bitmask
-
-// MaskBit is a flag container.
-type MaskBit uint8
-
-/*
-	NewMaskBit is a convenience function.
-	It will return a MaskBit with a (referenced) value of 0, so set your consts up accordingly.
-	It is highly recommended to set this default as a "None" flag (separate from your iotas!)
-	as shown in the example.
-*/
-func NewMaskBit() (m *MaskBit) {
-
-	m = new(MaskBit)
-
-	return
-}
-
-// HasFlag is true if m has MaskBit flag set/enabled.
-func (m *MaskBit) HasFlag(flag MaskBit) (r bool) {
-
-	var b MaskBit = *m
-
-	if b&flag != 0 {
-		r = true
-	}
-	return
-}
-
-// AddFlag adds MaskBit flag to m.
-func (m *MaskBit) AddFlag(flag MaskBit) {
-	*m |= flag
-	return
-}
-
-// ClearFlag removes MaskBit flag from m.
-func (m *MaskBit) ClearFlag(flag MaskBit) {
-	*m &= flag
-	return
-}
-
-// ToggleFlag switches MaskBit flag in m to its inverse; if true, it is now false and vice versa.
-func (m *MaskBit) ToggleFlag(flag MaskBit) {
-	*m ^= flag
-	return
-}

bitmask/doc.go

@@ -11,18 +11,18 @@ To use this, set constants like thus:
 		"r00t2.io/goutils/bitmask"
 	)
 
-	const OPTNONE types.MaskBit = 0
+	const OPTNONE bitmask.MaskBit = 0
 	const (
-		OPT1 types.MaskBit = 1 << iota
+		OPT1 bitmask.MaskBit = 1 << iota
 		OPT2
 		OPT3
 		// ...
 	)
 
-	var MyMask *MaskBit
+	var MyMask *bitmask.MaskBit
 
 	func main() {
-		MyMask = types.NewMaskBit
+		MyMask = bitmask.NewMaskBit()
 
 		MyMask.AddFlag(OPT1)
 		MyMask.AddFlag(OPT3)
@@ -41,5 +41,13 @@ As would this:
 But this would return false:
 
 	MyMask.HasFlag(OPT2)
+
+If you need something with more flexibility (as always, at the cost of complexity),
+you may be interested in one of the following libraries:
+
+. github.com/alvaroloes/enumer
+. github.com/abice/go-enum
+. github.com/jeffreyrichter/enum/enum
+
 */
 package bitmask