used size ring buffer rather than channel

ringbuffer/RingBuffer.go

@@ -38,7 +38,8 @@ RingBuffer aims to provide functionality of a RingBuffer data structure.
 It may be used in concurrent routines.
 */
 type ringBuffer struct {
-	memory           [][]byte
+	dataMemory       [][]byte
+	sizeMemory       []int
 	size             int
 	noOfElements     int
 	first            int
@@ -51,17 +52,18 @@ type ringBuffer struct {
 
 /*
 New returns the addres of a new ring buffer with the parameters specified.
-It initialises fields and allocates the required memory.
+It initialises fields and allocates the required dataMemory.
 */
 func NewRingBuffer(size int, elementSize int) (rb *ringBuffer) {
 	if size <= 0 || elementSize <= 0 {
 		return nil
 	}
 	rb = new(ringBuffer)
-	rb.memory = make([][]byte, size)
+	rb.dataMemory = make([][]byte, size)
-	for i := range rb.memory {
+	for i := range rb.dataMemory {
-		rb.memory[i] = make([]byte, elementSize)
+		rb.dataMemory[i] = make([]byte, elementSize)
 	}
+	rb.sizeMemory = make([]int, size)
 	rb.size = size
 	rb.noOfElements = 0
 	rb.first = -1
@@ -70,7 +72,7 @@ func NewRingBuffer(size int, elementSize int) (rb *ringBuffer) {
 	rb.currentlyReading = false
 	rb.sizeChannel = make(chan int, size)
 	rb.mutex = sync.Mutex{}
-	return 
+	return
 }
 
 /*
@@ -92,7 +94,7 @@ func (rb *ringBuffer) Get() ([]byte, error) {
 	if nextlast == rb.size {
 		nextlast = 0
 	}
-	return rb.memory[nextlast], nil
+	return rb.dataMemory[nextlast], nil
 }
 
 /*
@@ -109,11 +111,11 @@ func (rb *ringBuffer) DoneWriting(size int) error {
 	if rb.first == -1 {
 		rb.first++
 	}
-	rb.sizeChannel <- size
 	rb.last++
 	if rb.last == rb.size {
 		rb.last = 0
 	}
+	rb.sizeMemory[rb.last] = size 	 	
 	rb.noOfElements++
 	rb.currentlyWriting = false
 	return nil
@@ -126,17 +128,17 @@ calls to Get. The address of the data is returned, as well as the size of
 the data contained at this address. An error is returned if the buffer is
 empty, or there has been a second call to Read before a call to DoneReading.
 */
-func (rb *ringBuffer) Read() ([]byte, int, error) {
+func (rb *ringBuffer) Read() ([]byte, error) {
 	rb.mutex.Lock()
 	defer rb.mutex.Unlock()
 	if !rb.CanRead() {
-		return nil, 0, errors.New("Buffer is empty, nothging to read!")
+		return nil, errors.New("Buffer is empty, nothging to read!")
 	}
 	if rb.currentlyReading {
-		return nil, 0, errors.New("Second call to Read! Call DoneReading first!")
+		return nil, errors.New("Second call to Read! Call DoneReading first!")
 	}
 	rb.currentlyReading = true
-	return rb.memory[rb.first], <-rb.sizeChannel, nil
+	return rb.dataMemory[rb.first][:rb.sizeMemory[rb.first]], nil
 }
 
 /*

ringbuffer/RingBuffer_test.go

@@ -49,10 +49,10 @@ func noErrorFail(t *testing.T) {
 // size of 10 and arbitrary element size of 10
 func TestMake(t *testing.T) {
 	rb = NewRingBuffer(10, 10)
-	if len(rb.memory) != 10 {
+	if len(rb.dataMemory) != 10 {
 		t.Errorf("Len of buffer is wrong!")
 	}
-	if len(rb.memory[0]) != 10 {
+	if len(rb.dataMemory[0]) != 10 {
 		t.Errorf("Len of individual element is wrong!")
 	}
 }
@@ -100,7 +100,7 @@ func TestDoneReading1(t *testing.T) {
 // Test read when there hasn't been anything written to buffer
 func TestReadingWithoutWrite(t *testing.T) {
 	rb = NewRingBuffer(10, 10)
-	_, _, err := rb.Read()
+	_, err := rb.Read()
 	if err == nil {
 		noErrorFail(t)
 	}
@@ -121,7 +121,7 @@ func TestDoneReading2(t *testing.T) {
 	rb = NewRingBuffer(10, 10)
 	_, err := rb.Get()
 	rb.DoneWriting(1)
-	_, _, err = rb.Read()
+	_, err = rb.Read()
 	if err != nil {
 		falseErrorFail(t, err)
 	}
@@ -137,7 +137,7 @@ func TestWritingAndReading1(t *testing.T) {
 	if err := rb.DoneWriting(1); err != nil {
 		falseErrorFail(t, err)
 	}
-	if _, _, err := rb.Read(); err != nil {
+	if _, err := rb.Read(); err != nil {
 		falseErrorFail(t, err)
 	}
 	if err := rb.DoneReading(); err != nil {
@@ -157,7 +157,7 @@ func TestWritingAndReading2(t *testing.T) {
 		}
 	}
 	for i := 0; i < 2; i++ {
-		if _, _, err := rb.Read(); err != nil {
+		if _, err := rb.Read(); err != nil {
 			falseErrorFail(t, err)
 		}
 		if err := rb.DoneReading(); err != nil {
@@ -178,7 +178,7 @@ func TestWritingAndReading3(t *testing.T) {
 	var err1 error
 	var err2 error
 	for i := 0; i < 2; i++ {
-		_, _, err1 = rb.Read()
+		_, err1 = rb.Read()
 		err2 = rb.DoneReading()
 	}
 	if err1 == nil {
@@ -200,7 +200,7 @@ func TestWritingAndReading4(t *testing.T) {
 			falseErrorFail(t, err)
 		}
 	}
-	if _, _, err := rb.Read(); err != nil {
+	if _, err := rb.Read(); err != nil {
 		falseErrorFail(t, err)
 	}
 	if err := rb.DoneReading(); err != nil {
@@ -242,7 +242,7 @@ func TestWritingAndReading6(t *testing.T) {
 		falseErrorFail(t, err2)
 	}
 	for i := 0; i < 2; i++ {
-		_, _, err1 = rb.Read()
+		_, err1 = rb.Read()
 		err2 = rb.DoneReading()
 	}
 	if err1 != nil {
@@ -278,7 +278,7 @@ func TestWritingAndReading7(t *testing.T) {
 		falseErrorFail(t, err2)
 	}
 	for i := 0; i < 2; i++ {
-		_, _, err1 = rb.Read()
+		_, err1 = rb.Read()
 		err2 = rb.DoneReading()
 	}
 	if err1 != nil {
@@ -315,7 +315,7 @@ func TestWritingAndReading8(t *testing.T) {
 		falseErrorFail(t, err2)
 	}
 	for i := 0; i < 2; i++ {
-		_, _, err1 = rb.Read()
+		_, err1 = rb.Read()
 	}
 	if err1 == nil {
 		noErrorFail(t)
@@ -329,7 +329,7 @@ func TestConcurrency1(t *testing.T) {
 	rb = NewRingBuffer(1000, 10)
 	go func() {
 		for i := 0; i < 100; i++ {
-			if data, _, err1 := rb.Read(); data != nil {
+			if data, err1 := rb.Read(); data != nil {
 				err2 := rb.DoneReading()
 				if err1 != nil {
 					falseErrorFail(t, err1)