From 57307c274c40936dda1d5f67b4bcf8803dcb5b41 Mon Sep 17 00:00:00 2001
From: qydysky <qydysky@foxmail.com>
Date: Thu, 14 Dec 2023 22:26:12 +0800
Subject: [PATCH] 1

---
 slice/Blocks.go      | 45 ++++++++++++++++++++++++++++++++++++++++++++
 slice/Blocks_test.go | 12 ++++++++++++
 2 files changed, 57 insertions(+)
 create mode 100644 slice/Blocks.go
 create mode 100644 slice/Blocks_test.go

diff --git a/slice/Blocks.go b/slice/Blocks.go
new file mode 100644
index 0000000..5de6c8a
--- /dev/null
+++ b/slice/Blocks.go
@@ -0,0 +1,45 @@
+package part
+
+import (
+	"errors"
+)
+
+type blocks[T any] struct {
+	free chan int
+	size int
+	buf  []T
+}
+
+var ErrOverflow = errors.New("ErrOverflow")
+
+func NewBlocks[T any](blockSize int, blockNum int) *blocks[T] {
+	p := &blocks[T]{
+		size: blockSize,
+		free: make(chan int, blockNum+1),
+		buf:  make([]T, blockSize*blockNum),
+	}
+	for i := 0; i < blockNum; i++ {
+		p.free <- i
+	}
+	return p
+}
+
+// // eg
+//
+//	if tmpbuf, putBack, e := buf.Get(); e == nil {
+//		clear(tmpbuf)
+//		// do something with tmpbuf
+//		putBack()
+//	}
+func (t *blocks[T]) Get() ([]T, func(), error) {
+	select {
+	case offset := <-t.free:
+		offset *= t.size
+		return t.buf[offset : offset+t.size], func() {
+			clear(t.buf[offset : offset+t.size])
+			t.free <- offset
+		}, nil
+	default:
+		return nil, func() {}, ErrOverflow
+	}
+}
diff --git a/slice/Blocks_test.go b/slice/Blocks_test.go
new file mode 100644
index 0000000..b6eae39
--- /dev/null
+++ b/slice/Blocks_test.go
@@ -0,0 +1,12 @@
+package part
+
+import "testing"
+
+func TestMain(t *testing.T) {
+	buf := NewBlocks[byte](1024, 10)
+	if tmpbuf, putBack, e := buf.Get(); e == nil {
+		clear(tmpbuf)
+		// do something with tmpbuf
+		putBack()
+	}
+}
-- 
2.39.2