From f1b82e5bfd98aa6d8e6229363f0ca0ecbcabd426 Mon Sep 17 00:00:00 2001
From: qydysky <qydysky@foxmail.com>
Date: Sat, 16 Mar 2024 17:43:55 +0800
Subject: [PATCH] slices.Buf[T any].GetPureBufRLock

---
 slice/Slice.go      | 12 ++++++++++++
 slice/Slice_test.go | 31 +++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+)

diff --git a/slice/Slice.go b/slice/Slice.go
index 046b726..8f028b0 100644
--- a/slice/Slice.go
+++ b/slice/Slice.go
@@ -151,6 +151,18 @@ func (t *Buf[T]) GetPureBuf() (buf []T) {
 	return t.buf[:t.bufsize]
 }
 
+// must call unlock
+//
+// buf will no modify before unlock
+//
+// modify func(eg Reset) with block until unlock
+//
+// unsafe
+func (t *Buf[T]) GetPureBufRLock() (buf []T, unlock func()) {
+	t.l.RLock()
+	return t.buf[:t.bufsize], t.l.RUnlock
+}
+
 func (t *Buf[T]) GetCopyBuf() (buf []T) {
 	t.l.RLock()
 	defer t.l.RUnlock()
diff --git a/slice/Slice_test.go b/slice/Slice_test.go
index 61db09f..2da7059 100644
--- a/slice/Slice_test.go
+++ b/slice/Slice_test.go
@@ -106,3 +106,34 @@ func Test3(t *testing.T) {
 		t.Fatal()
 	}
 }
+
+func Test4(t *testing.T) {
+	var c = New[byte]()
+	var w = make(chan struct{})
+
+	c.Append([]byte("12345"))
+
+	buf, unlock := c.GetPureBufRLock()
+
+	go func() {
+		w <- struct{}{}
+		c.Reset()
+		t.Log(c.Append([]byte("22345")))
+		t.Log(c.buf)
+		w <- struct{}{}
+	}()
+
+	<-w
+
+	if !bytes.Equal(buf, []byte("12345")) {
+		t.Fatal()
+	}
+
+	unlock()
+
+	<-w
+
+	if !bytes.Equal(buf, []byte("22345")) {
+		t.Fatal(buf)
+	}
+}
-- 
2.39.2