fix(all): impl. new apis to make sure safety

item.go

@@ -2,7 +2,6 @@ package orbyte
 
 import (
 	"runtime"
-	"strconv"
 	"sync/atomic"
 )
 
@@ -16,96 +15,59 @@ type Item[T any] struct {
 	cfg  any
 
 	stat status
-	ref  *Item[T]
-	refc int32 // refc -1 means transferred / destroyed
 
 	val T
 }
 
-func (b *Item[T]) incref() {
-	atomic.AddInt32(&b.refc, 1)
-}
-
-func (b *Item[T]) decref() {
-	atomic.AddInt32(&b.refc, -1)
-}
-
-// Trans ownership to a new item and
-// destroy original item immediately.
+// Trans disable inner val being reset by
+// destroy and return a safe copy of val.
 //
-// The value in new item will not be Reset().
+// This method is not thread-safe.
+// Only call once on one item.
+// The item will be destroyed after calling Trans().
 //
-// Call this function to drop your ownership
-// before passing it to another function
-// that is not controlled by you.
-//
-// Avoid to call this function after calling Ref().
-func (b *Item[T]) Trans() (tb *Item[T]) {
+// Use it to drop your ownership
+// before passing val (not its pointer)
+// to another function that is not controlled by you.
+func (b *Item[T]) Trans() T {
 	if b.stat.hasdestroyed() {
 		panic("use after destroy")
 	}
-	if b.ref != nil {
-		panic("cannot trans ref")
-	}
-	tb = b.pool.newempty()
-	*tb = *b
-	tb.stat = status(atomic.SwapUintptr(
+	val := b.val
+	atomic.StoreUintptr(
 		(*uintptr)(&b.stat), uintptr(destroyedstatus),
-	))
-	tb.refc = 0
-	tb.stat.setintrans(true)
-	b.destroybystat(status(0))
-	return tb
+	)
+	runtime.KeepAlive(b)
+	b.destroybystat(0)
+	return val
 }
 
-// HasInvolved whether this item is buffered.
+// HasInvolved whether this item is buffered
+// and will be Reset on putting back.
 func (b *Item[T]) HasInvolved() bool {
 	return b.stat.isbuffered()
 }
 
-// IsTrans whether this item has been marked as trans.
-func (b *Item[T]) IsTrans() bool {
-	return b.stat.isintrans()
-}
-
-// IsRef whether this item is a reference.
-func (b *Item[T]) IsRef() bool {
-	return b.ref != nil
-}
-
-// Unwrap use value of the item
-func (b *Item[T]) Unwrap() T {
-	if b.stat.hasdestroyed() {
-		panic("use after destroy")
-	}
-	return b.val
-}
-
-// Pointer use pointer value of the item
-func (b *Item[T]) Pointer() *T {
-	if b.stat.hasdestroyed() {
-		panic("use after destroy")
-	}
-	return &b.val
-}
-
-// Ref gens new item without ownership.
+// V use value of the item.
 //
-// It's a safe reference, thus calling this
-// will not destroy the original item
-// comparing with Trans().
-func (b *Item[T]) Ref() (rb *Item[T]) {
+// This operation is safe in function f.
+func (b *Item[T]) V(f func(T)) {
 	if b.stat.hasdestroyed() {
 		panic("use after destroy")
 	}
-	rb = b.pool.newempty()
-	*rb = *b
-	rb.ref = b
-	rb.refc = 0
-	b.incref()
-	rb.stat.setbuffered(false)
-	rb.stat.setintrans(false)
-	return
+	f(b.val)
+	runtime.KeepAlive(b)
+}
+
+// P use pointer value of the item.
+//
+// This operation is safe in function f.
+func (b *Item[T]) P(f func(*T)) {
+	if b.stat.hasdestroyed() {
+		panic("use after destroy")
+	}
+	f(&b.val)
+	runtime.KeepAlive(b)
 }
 
 // Copy data completely with separated ownership.
@@ -119,21 +81,9 @@ func (b *Item[T]) Copy() (cb *Item[T]) {
 }
 
 func (b *Item[T]) destroybystat(stat status) {
-	if !atomic.CompareAndSwapInt32(&b.refc, 0, -1) {
-		if b.refc < 0 {
-			panic("use imm. after destroy")
-		}
-		panic("cannot destroy: " + strconv.Itoa(int(b.refc)) + " refs remained")
-	}
-	if b.ref != nil {
-		defer b.ref.decref()
-	}
 	switch {
 	case stat.hasdestroyed():
-		panic("use after put back to pool")
-	case stat.isintrans():
-		var v T
-		b.val = v
+		panic("destroy after destroy")
 	case stat.isbuffered():
 		b.pool.pooler.Reset(&b.val)
 	default:
@@ -158,10 +108,10 @@ func (b *Item[T]) ManualDestroy() {
 // Only can call once.
 func (b *Item[T]) setautodestroy() *Item[T] {
 	runtime.SetFinalizer(b, func(item *Item[T]) {
-		// no one is using, no concurrency issue.
 		if item.stat.hasdestroyed() {
 			panic("unexpected hasdestroyed")
 		}
+		// no one is using, no concurrency issue.
 		item.destroybystat(item.stat)
 	})
 	return b

pbuf/buffer.go

@@ -2,7 +2,6 @@ package pbuf
 
 import (
 	"bytes"
-	"unsafe"
 
 	"github.com/fumiama/orbyte"
 )
@@ -21,54 +20,3 @@ func (bufferPool BufferPool) InvolveBuffer(buf *bytes.Buffer) *orbyte.Item[bytes
 func (bufferPool BufferPool) ParseBuffer(buf *bytes.Buffer) *orbyte.Item[bytes.Buffer] {
 	return bufferPool.p.Parse(buf.Len(), buf)
 }
-
-// A Buffer is a variable-sized buffer of bytes with Read and Write methods.
-// The zero value for Buffer is an empty buffer ready to use.
-type buffer struct {
-	buf      []byte // contents are the bytes buf[off : len(buf)]
-	off      int    // read at &buf[off], write at &buf[len(buf)]
-	lastRead readOp // last read operation, so that Unread* can work correctly.
-}
-
-func skip(w *bytes.Buffer, n int) {
-	if n == 0 {
-		return
-	}
-	b := (*buffer)(unsafe.Pointer(w))
-	b.lastRead = opInvalid
-	if len(b.buf) <= b.off {
-		// Buffer is empty, reset to recover space.
-		w.Reset()
-		return
-	}
-	n = minnum(n, len(b.buf[b.off:]))
-	b.off += n
-	if n > 0 {
-		b.lastRead = opRead
-	}
-}
-
-// The readOp constants describe the last action performed on
-// the buffer, so that UnreadRune and UnreadByte can check for
-// invalid usage. opReadRuneX constants are chosen such that
-// converted to int they correspond to the rune size that was read.
-type readOp int8
-
-// Don't use iota for these, as the values need to correspond with the
-// names and comments, which is easier to see when being explicit.
-const (
-	opRead      readOp = -1 // Any other read operation.
-	opInvalid   readOp = 0  // Non-read operation.
-	opReadRune1 readOp = 1  // Read rune of size 1.
-	opReadRune2 readOp = 2  // Read rune of size 2.
-	opReadRune3 readOp = 3  // Read rune of size 3.
-	opReadRune4 readOp = 4  // Read rune of size 4.
-)
-
-// minnum 返回两数最小值，该函数将被内联
-func minnum[T int | int8 | uint8 | int16 | uint16 | int32 | uint32 | int64 | uint64](a, b T) T {
-	if a > b {
-		return b
-	}
-	return a
-}

pbuf/buffer_test.go

@@ -20,38 +20,24 @@ func TestBuffer(t *testing.T) {
 }
 
 func testBuffer(buf *orbyte.Item[bytes.Buffer], t *testing.T) {
-	if buf.Pointer().Len() != 4096 {
-		io.CopyN(buf.Pointer(), rand.Reader, 4096)
-		if buf.Pointer().Len() != 4096 {
-			t.Fatal("got", buf.Pointer().Len())
+	buf.P(func(buf *bytes.Buffer) {
+		if buf.Len() != 4096 {
+			io.CopyN(buf, rand.Reader, 4096)
+			if buf.Len() != 4096 {
+				t.Fatal("got", buf.Len())
+			}
 		}
-	}
-
+	})
 	bufcp := buf.Copy()
-	if bufcp.Pointer().Len() != 4096 {
-		t.Fatal("got", bufcp.Pointer().Len())
-	}
-	if !bytes.Equal(bufcp.Pointer().Bytes(), buf.Pointer().Bytes()) {
-		t.Fatal("unexpected")
-	}
-
-	bufr := buf.Ref()
-	if bufr.Pointer().Len() != 4096 {
-		t.Fatal("got", bufr.Pointer().Len())
-	}
-	if !bytes.Equal(bufr.Pointer().Bytes(), buf.Pointer().Bytes()) {
-		t.Fatal("unexpected")
-	}
-	bufr.ManualDestroy()
-
-	bufcp = bufcp.Trans()
-	if bufcp.Pointer().Len() != 4096 {
-		t.Fatal("got", bufcp.Pointer().Len())
-	}
-	if !bytes.Equal(bufcp.Pointer().Bytes(), buf.Pointer().Bytes()) {
-		t.Fatal("unexpected")
-	}
-	bufcp.ManualDestroy()
+	dat := buf.Trans()
+	bufcp.P(func(bufcp *bytes.Buffer) {
+		if bufcp.Len() != 4096 {
+			t.Fatal("got", bufcp.Len())
+		}
+		if !bytes.Equal(bufcp.Bytes(), dat.Bytes()) {
+			t.Fatal("unexpected")
+		}
+	})
 
 	runtime.GC()
 	runtime.Gosched()

pbuf/bytes.go

@@ -2,7 +2,6 @@ package pbuf
 
 import (
 	"bytes"
-	"runtime"
 
 	"github.com/fumiama/orbyte"
 )
@@ -10,8 +9,8 @@ import (
 // Bytes wrap pooled buffer into []byte
 // while sharing the same pool.
 type Bytes struct {
-	buf *orbyte.Item[bytes.Buffer]
-	dat []byte
+	buf  *orbyte.Item[bytes.Buffer]
+	a, b int
 }
 
 // BufferItemToBytes convert between *orbyte.Item[bytes.Buffer]
@@ -19,27 +18,43 @@ type Bytes struct {
 //
 // Please notice that Bytes cannnot convert back to
 // *orbyte.Item[bytes.Buffer] again.
-func BufferItemToBytes(buf *orbyte.Item[bytes.Buffer]) Bytes {
-	return Bytes{buf: buf, dat: buf.Pointer().Bytes()}
+func BufferItemToBytes(buf *orbyte.Item[bytes.Buffer]) (b Bytes) {
+	b.buf = buf
+	buf.P(func(buf *bytes.Buffer) {
+		b.b = buf.Len()
+	})
+	return
 }
 
 // NewBytes alloc sz bytes.
-func (bufferPool BufferPool) NewBytes(sz int) Bytes {
+func (bufferPool BufferPool) NewBytes(sz int) (b Bytes) {
 	buf := bufferPool.p.New(sz)
-	return Bytes{buf: buf, dat: buf.Pointer().Bytes()[:sz]}
+	b.buf = buf
+	buf.P(func(buf *bytes.Buffer) {
+		b.b = buf.Len()
+	})
+	return
 }
 
 // InvolveBytes involve outside buf into pool.
-func (bufferPool BufferPool) InvolveBytes(b ...byte) Bytes {
-	buf := bufferPool.p.Involve(len(b), bytes.NewBuffer(b))
-	return Bytes{buf: buf, dat: buf.Pointer().Bytes()[:len(b)]}
+func (bufferPool BufferPool) InvolveBytes(p ...byte) (b Bytes) {
+	buf := bufferPool.p.Involve(len(p), bytes.NewBuffer(p))
+	b.buf = buf
+	buf.P(func(buf *bytes.Buffer) {
+		b.b = buf.Len()
+	})
+	return
 }
 
 // ParseBytes convert outside bytes to Bytes safely
 // without adding it into pool.
-func (bufferPool BufferPool) ParseBytes(b ...byte) Bytes {
-	buf := bufferPool.p.Parse(len(b), bytes.NewBuffer(b))
-	return Bytes{buf: buf, dat: buf.Pointer().Bytes()}
+func (bufferPool BufferPool) ParseBytes(p ...byte) (b Bytes) {
+	buf := bufferPool.p.Parse(len(p), bytes.NewBuffer(p))
+	b.buf = buf
+	buf.P(func(buf *bytes.Buffer) {
+		b.b = buf.Len()
+	})
+	return
 }
 
 // HasInit whether this Bytes is made by pool or
@@ -49,89 +64,49 @@ func (b Bytes) HasInit() bool {
 }
 
 // Trans please refer to Item.Trans().
-func (b Bytes) Trans() (tb Bytes) {
-	tb.buf = b.buf.Trans()
-	tb.dat = b.dat
-	return
+func (b Bytes) Trans() []byte {
+	buf := b.buf.Trans()
+	return buf.Bytes()[b.a:b.b]
 }
 
 // Len of slice.
 func (b Bytes) Len() int {
-	return len(b.dat)
+	return b.b - b.a
 }
 
 // Cap of slice.
-func (b Bytes) Cap() int {
-	return cap(b.dat)
+func (b Bytes) Cap() (c int) {
+	b.buf.P(func(b *bytes.Buffer) {
+		c = b.Cap()
+	})
+	return c
 }
 
-// Bytes is the inner value.
-func (b Bytes) Bytes() []byte {
-	return b.dat
-}
-
-// Ref please refer to Item.Ref().
-func (b Bytes) Ref() (rb Bytes) {
-	rb.buf = b.buf.Ref()
-	rb.dat = b.dat
-	return
+// V use the inner value safely
+func (b Bytes) V(f func([]byte)) {
+	b.buf.P(func(buf *bytes.Buffer) {
+		f(buf.Bytes()[b.a:b.b])
+	})
 }
 
 // Copy please refer to Item.Copy().
 func (b Bytes) Copy() (cb Bytes) {
 	cb.buf = b.buf.Copy()
-	cb.dat = cb.buf.Pointer().Bytes()
+	cb.a, cb.b = b.a, b.b
 	return
 }
 
 // SliceFrom dat[from:] with Ref.
 func (b Bytes) SliceFrom(from int) Bytes {
-	if b.buf.IsTrans() {
-		if b.buf.HasInvolved() {
-			return InvolveBytes(b.dat[from:]...)
-		}
-		return ParseBytes(b.dat[from:]...)
-	}
-	nb := b.Ref()
-	skip(nb.buf.Pointer(), from)
-	nb.dat = b.dat[from:]
-	return nb
+	return Bytes{buf: b.buf, a: b.a + from, b: b.b}
 }
 
 // SliceTo dat[:to] with Ref.
 func (b Bytes) SliceTo(to int) Bytes {
-	if b.buf.IsTrans() {
-		if b.buf.HasInvolved() {
-			return InvolveBytes(b.dat[:to]...)
-		}
-		return ParseBytes(b.dat[:to]...)
-	}
-	nb := b.Ref()
-	nb.buf.Pointer().Truncate(to)
-	nb.dat = b.dat[:to]
-	return nb
+	return Bytes{buf: b.buf, a: b.a, b: b.a + to}
 }
 
 // Slice dat[from:to] with Ref.
 func (b Bytes) Slice(from, to int) Bytes {
-	if b.buf.IsTrans() {
-		if b.buf.HasInvolved() {
-			return InvolveBytes(b.dat[from:to]...)
-		}
-		return ParseBytes(b.dat[from:to]...)
-	}
-	nb := b.Ref()
-	buf := nb.buf.Pointer()
-	skip(buf, from)
-	buf.Truncate(to - from)
-	nb.dat = b.dat[from:to]
-	return nb
-}
-
-// KeepAlive marks Bytes value as reachable.
-func (b Bytes) KeepAlive() {
-	_ = b.buf
-	_ = b.dat
-	runtime.KeepAlive(b.buf)
-	runtime.KeepAlive(b.dat)
+	return Bytes{buf: b.buf, a: b.a + from, b: b.a + to}
 }

pbuf/bytes_test.go

@@ -11,13 +11,6 @@ import (
 	"time"
 )
 
-// manualDestroy please refer to Item.manualDestroy().
-//
-// Only for test purposes.
-func (b Bytes) manualDestroy() {
-	b.buf.ManualDestroy()
-}
-
 // TestBytesSlice sometimes fails at first run because
 // GC not collecting all unused items.
 func TestBytesSlice(t *testing.T) {
@@ -26,27 +19,20 @@ func TestBytesSlice(t *testing.T) {
 		if b.Len() != i {
 			t.Fatal("index", i, "excpet len", i, "but got", b.Len())
 		}
-		rand.Read(b.Bytes())
+		b.V(func(b []byte) {
+			rand.Read(b)
+		})
 		buf := make([]byte, b.Len())
-		copy(buf, b.Bytes())
-		// test normal slice
-		y := b.SliceFrom(5)
-		x := y.SliceTo(i - 5 - 5)
-		if !bytes.Equal(buf[5:i-5], x.Bytes()) {
+		b.V(func(b []byte) {
+			copy(buf, b)
+		})
+		x := b.SliceFrom(5).SliceTo(i - 5 - 5)
+		dat := x.Trans()
+		if !bytes.Equal(buf[5:i-5], dat) {
 			t.Log("exp:", hex.EncodeToString(buf[5:i-5]))
-			t.Log("got:", hex.EncodeToString(x.Bytes()))
+			t.Log("got:", hex.EncodeToString(dat))
 			t.Fatal("index", i, "unexpected")
 		}
-		x.manualDestroy()
-		y.manualDestroy()
-		// test trans slice
-		b = b.Trans().SliceFrom(5).SliceTo(i - 5 - 5)
-		if !bytes.Equal(buf[5:i-5], b.Bytes()) {
-			t.Log("exp:", hex.EncodeToString(buf[5:i-5]))
-			t.Log("got:", hex.EncodeToString(b.Bytes()))
-			t.Fatal("index", i, "unexpected")
-		}
-		b.manualDestroy()
 	}
 	runtime.GC()
 	runtime.Gosched()
@@ -66,11 +52,12 @@ func TestBytesInvolve(t *testing.T) {
 		if b.Len() != i {
 			t.Fatal("index", i, "excpet len", i, "but got", b.Len())
 		}
-		rand.Read(b.Bytes())
-		if !bytes.Equal(b.Bytes(), buf[:i]) {
+		b.V(func(b []byte) {
+			rand.Read(b)
+		})
+		if !bytes.Equal(b.Trans(), buf[:i]) {
 			t.Fatal("index", i, "unexpected")
 		}
-		b.manualDestroy()
 	}
 	runtime.GC()
 	out, in := bufferPool.p.CountItems()
@@ -88,10 +75,9 @@ func TestBytesParse(t *testing.T) {
 		if b.Len() != i {
 			t.Fatal("index", i, "excpet len", i, "but got", b.Len())
 		}
-		if !bytes.Equal(b.Bytes(), buf[:i]) {
+		if !bytes.Equal(b.Trans(), buf[:i]) {
 			t.Fatal("index", i, "unexpected")
 		}
-		b.manualDestroy()
 	}
 	runtime.GC()
 	out, in := bufferPool.p.CountItems()
@@ -111,15 +97,12 @@ func TestBytesCopy(t *testing.T) {
 		if b.Len() != i-10 {
 			t.Fatal("index", i, "excpet len", i, "but got", b.Len())
 		}
-		rand.Read(b.Bytes())
-		// t.Log("org:", hex.EncodeToString(buf[:i]))
-		// t.Log("new:", hex.EncodeToString(b.Bytes()))
-		if bytes.Equal(b.Bytes(), buf[:i]) {
+		b.V(func(b []byte) {
+			rand.Read(b)
+		})
+		if bytes.Equal(b.Trans(), buf[:i]) {
 			t.Fatal("index", i, "unexpected")
 		}
-		b.manualDestroy()
-		x.manualDestroy()
-		a.manualDestroy()
 	}
 	runtime.GC()
 	runtime.Gosched()
@@ -141,15 +124,16 @@ func TestBytesTransMultithread(t *testing.T) {
 			buf := NewBytes(65536)
 			refer := make([]byte, 65536)
 			rand.Read(refer)
-			copy(buf.Bytes(), refer)
+			buf.V(func(b []byte) {
+				copy(b, refer)
+			})
 			wg.Add(1)
-			go func(buf Bytes) {
+			go func(buf []byte) {
 				defer wg.Done()
 				time.Sleep(time.Millisecond * time.Duration(mrand.Intn(10)))
-				if !bytes.Equal(refer, buf.Bytes()) {
+				if !bytes.Equal(refer, buf) {
 					panic("unexpected")
 				}
-				buf.manualDestroy()
 			}(buf.Trans())
 		}()
 	}

pool.go

@@ -77,8 +77,6 @@ func (pool *Pool[T]) put(item *Item[T]) {
 	item.cfg = nil
 
 	item.stat.setdestroyed(true)
-	item.ref = nil
-	item.refc = 0
 
 	if pool.noputbak {
 		return

pool_test.go

@@ -32,14 +32,10 @@ func TestPool(t *testing.T) {
 	wg := sync.WaitGroup{}
 	for i := 0; i < 4096; i++ {
 		item := p.New(i)
-		for j := 0; j < 16; j++ {
-			wg.Add(1)
-			user(item.Ref(), &wg)
-			wg.Add(1)
-			go usernodestroy(item.Copy(), &wg)
-		}
 		wg.Add(1)
-		go usernodestroy(item.Trans(), &wg)
+		go useranddes(item.Copy(), &wg)
+		wg.Add(1)
+		go userv(item.Trans(), &wg)
 	}
 	wg.Wait()
 	runtime.GC()
@@ -50,15 +46,17 @@ func TestPool(t *testing.T) {
 	}
 }
 
-func user(item *Item[[]byte], wg *sync.WaitGroup) {
+func useranddes(item *Item[[]byte], wg *sync.WaitGroup) {
 	defer wg.Done()
-	rand.Read(item.Unwrap())
+	item.V(func(b []byte) {
+		rand.Read(b)
+	})
 	item.ManualDestroy()
 }
 
-func usernodestroy(item *Item[[]byte], wg *sync.WaitGroup) {
+func userv(b []byte, wg *sync.WaitGroup) {
 	defer wg.Done()
-	rand.Read(item.Unwrap())
+	rand.Read(b)
 }
 
 type simplepooler struct{}

status.go

@@ -5,7 +5,6 @@ import "sync/atomic"
 const (
 	statusisbuffered = 1 << iota
 	statusdestroyed
-	statusisintrans
 )
 
 type status uintptr
@@ -58,11 +57,3 @@ func (c *status) hasdestroyed() bool {
 func (c *status) setdestroyed(v bool) {
 	c.setbool(v, statusdestroyed)
 }
-
-func (c *status) isintrans() bool {
-	return c.loadbool(statusisintrans)
-}
-
-func (c *status) setintrans(v bool) {
-	c.setbool(v, statusisintrans)
-}