76 lines
1.0 KiB
Go
76 lines
1.0 KiB
Go
package ringbuffer
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import (
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"sync"
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)
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type RingBuffer struct {
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buffer []string
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size int
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head int
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tail int
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mu sync.Mutex
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}
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func NewRingBuffer(size int) *RingBuffer {
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return &RingBuffer{
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buffer: make([]string, size),
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size: size,
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head: -1,
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tail: -1,
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}
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}
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func (rb *RingBuffer) Add(item string) {
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rb.mu.Lock()
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defer rb.mu.Unlock()
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if (rb.tail+1)%rb.size == rb.head {
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rb.head = (rb.head + 1) % rb.size
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}
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rb.tail = (rb.tail + 1) % rb.size
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rb.buffer[rb.tail] = item
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if rb.head == -1 {
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rb.head = rb.tail
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}
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}
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func (rb *RingBuffer) GetLast() (string, int) {
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rb.mu.Lock()
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defer rb.mu.Unlock()
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if rb.head == -1 {
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return "", -1
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}
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return rb.buffer[rb.tail], rb.tail
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}
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func (rb *RingBuffer) WaitForNewItem() string {
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rb.mu.Lock()
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defer rb.mu.Unlock()
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if rb.tail == -1 {
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return ""
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}
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return rb.buffer[rb.tail]
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}
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func (rb *RingBuffer) IsEmpty() bool {
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rb.mu.Lock()
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defer rb.mu.Unlock()
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return rb.head == -1
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}
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func (rb *RingBuffer) GetLastPosition() int {
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rb.mu.Lock()
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defer rb.mu.Unlock()
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return rb.tail
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}
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