[refactor] package nazabits: BitReader::ReadBits -> ReadBits8, BitWriter::WriteBits -> WriteBits8 and WriteBits16

pkg/nazabits/bits.go

@@ -34,9 +34,9 @@ func (br *BitReader) ReadBit() uint8 {
 	return res
 }
 
-// 目前限制一次最多读8位，需调用方自己保证。如果需要读取大于8位，可以分多次读，或者以后把限制放开
+// 如果需要读取大于8位，可以分多次读，以后可能加上ReadBits16等接口
 // @param n: 取值范围 [1, 8]
-func (br *BitReader) ReadBits(n uint) (r uint8) {
+func (br *BitReader) ReadBits8(n uint) (r uint8) {
 	var i uint
 	for i = 0; i < n; i++ {
 		r = (r << 1) | br.ReadBit()
@@ -68,9 +68,18 @@ func (bw *BitWriter) WriteBit(b uint8) {
 	}
 }
 
-// @param n: 取值范围 [1, 16]
-// 目前限制一次最多写16位，大于16位可以分多次写，或者以后把限制放开
-func (bw *BitWriter) WriteBits(n uint, v uint16) {
+// 将<v>的低<n>位写入
+// @param n: 取值范围 [1, 8]
+func (bw *BitWriter) WriteBits8(n uint, v uint8) {
+	for i := n - 1; ; i-- {
+		bw.WriteBit(v >> i & 0x1)
+		if i == 0 {
+			break
+		}
+	}
+}
+
+func (bw *BitWriter) WriteBits16(n uint, v uint16) {
 	for i := n - 1; ; i-- {
 		bw.WriteBit(uint8(v >> i & 0x1))
 		if i == 0 {

pkg/nazabits/bits_test.go

@@ -97,19 +97,19 @@ func TestBitReader_ReadBits8(t *testing.T) {
 	br := nazabits.NewBitReader(v)
 	// {0 01 1 00 00, 00 11 100 1, 0011 0 000, 0011 1001}
 	//  0,01,1 00,00 00, 11 100,100110,   0000011,
-	assert.Equal(t, uint8(0), br.ReadBits(1))
-	assert.Equal(t, uint8(1), br.ReadBits(2))
-	assert.Equal(t, uint8(4), br.ReadBits(3))
-	assert.Equal(t, uint8(0), br.ReadBits(4))
-	assert.Equal(t, uint8(28), br.ReadBits(5))
-	assert.Equal(t, uint8(38), br.ReadBits(6))
-	assert.Equal(t, uint8(3), br.ReadBits(7))
+	assert.Equal(t, uint8(0), br.ReadBits8(1))
+	assert.Equal(t, uint8(1), br.ReadBits8(2))
+	assert.Equal(t, uint8(4), br.ReadBits8(3))
+	assert.Equal(t, uint8(0), br.ReadBits8(4))
+	assert.Equal(t, uint8(28), br.ReadBits8(5))
+	assert.Equal(t, uint8(38), br.ReadBits8(6))
+	assert.Equal(t, uint8(3), br.ReadBits8(7))
 
 	br = nazabits.NewBitReader(v)
 	// {0011 0000, 0011 1001, 0 011 0000, 0011 1001}
-	assert.Equal(t, uint8(48), br.ReadBits(8))
-	//assert.Equal(t, uint8(114), br.ReadBits(9))
-	//assert.Equal(t, uint8(385), br.ReadBits(10))
+	assert.Equal(t, uint8(48), br.ReadBits8(8))
+	//assert.Equal(t, uint8(114), br.ReadBits8(9))
+	//assert.Equal(t, uint8(385), br.ReadBits8(10))
 }
 
 func TestBitWriter_WriteBit(t *testing.T) {
@@ -132,26 +132,44 @@ func TestBitWriter_WriteBit(t *testing.T) {
 	assert.Equal(t, uint8(57), v[1])
 }
 
-func TestBitWriter_WriteBits(t *testing.T) {
+func TestBitWriter_WriteBits8(t *testing.T) {
 	v := make([]byte, 2)
 	bw := nazabits.NewBitWriter(v)
-	bw.WriteBits(1, 0)
-	bw.WriteBits(2, 1)
-	bw.WriteBits(3, 4)
-	bw.WriteBits(4, 0)
-	bw.WriteBits(5, 28)
-	bw.WriteBits(1, 1)
+	bw.WriteBits8(1, 0)
+	bw.WriteBits8(2, 1)
+	bw.WriteBits8(3, 4)
+	bw.WriteBits8(4, 0)
+	bw.WriteBits8(5, 28)
+	bw.WriteBits8(1, 1)
 	assert.Equal(t, uint8(48), v[0])
 	assert.Equal(t, uint8(57), v[1])
 
 	v = make([]byte, 1)
 	bw = nazabits.NewBitWriter(v)
-	bw.WriteBits(3, 1+8+32+128)
+	bw.WriteBits8(3, 1+8+32+128)
+	assert.Equal(t, uint8(1<<5), v[0])
+}
+
+func TestBitWriter_WriteBits16(t *testing.T) {
+	v := make([]byte, 2)
+	bw := nazabits.NewBitWriter(v)
+	bw.WriteBits16(1, 0)
+	bw.WriteBits16(2, 1)
+	bw.WriteBits16(3, 4)
+	bw.WriteBits16(4, 0)
+	bw.WriteBits16(5, 28)
+	bw.WriteBits16(1, 1)
+	assert.Equal(t, uint8(48), v[0])
+	assert.Equal(t, uint8(57), v[1])
+
+	v = make([]byte, 1)
+	bw = nazabits.NewBitWriter(v)
+	bw.WriteBits16(3, 1+8+32+128)
 	assert.Equal(t, uint8(1<<5), v[0])
 
 	v = make([]byte, 2)
 	bw = nazabits.NewBitWriter(v)
-	bw.WriteBits(16, 0xFFFF)
+	bw.WriteBits16(16, 0xFFFF)
 	assert.Equal(t, uint8(0xFF), v[0])
 	assert.Equal(t, uint8(0xFF), v[1])
 }
@@ -163,18 +181,18 @@ func BenchmarkGetBits16(b *testing.B) {
 	}
 }
 
-func BenchmarkBitReader_ReadBits(b *testing.B) {
+func BenchmarkBitReader_ReadBits8(b *testing.B) {
 	v := []byte{48, 57}
 	for i := 0; i < b.N; i++ {
 		br := nazabits.NewBitReader(v)
-		br.ReadBits(9)
+		br.ReadBits8(9)
 	}
 }
 
-func BenchmarkBitWriter_WriteBits(b *testing.B) {
+func BenchmarkBitWriter_WriteBits16(b *testing.B) {
 	v := make([]byte, 2)
 	for i := 0; i < b.N; i++ {
 		bw := nazabits.NewBitWriter(v)
-		bw.WriteBits(9, 28)
+		bw.WriteBits16(9, 28)
 	}
 }