reflection for channels

R=r
DELTA=188  (171 added, 6 deleted, 11 changed)
OCL=31352
CL=31361

src/pkg/reflect/all_test.go

@@ -598,7 +598,7 @@ func TestNilPtrValueSub(t *testing.T) {
 	}
 }
 
-func TestMapAccess(t *testing.T) {
+func TestMap(t *testing.T) {
 	m := map[string]int{ "a": 1, "b": 2 };
 	mv := NewValue(m).(*MapValue);
 	if n := mv.Len(); n != len(m) {
@@ -651,3 +651,77 @@ func TestMapAccess(t *testing.T) {
 		t.Errorf("newm[\"a\"] = %d after delete", v);
 	}
 }
+
+func TestChan(t *testing.T) {
+	for loop := 0; loop < 2; loop++ {
+		var c chan int;
+		var cv *ChanValue;
+
+		// check both ways to allocate channels
+		switch loop {
+		case 1:
+			c = make(chan int, 1);
+			cv = NewValue(c).(*ChanValue);
+		case 0:
+			cv = MakeChan(Typeof(c).(*ChanType), 1);
+			c = cv.Interface().(chan int);
+		}
+
+		// Send
+		cv.Send(NewValue(2));
+		if i := <-c; i != 2 {
+			t.Errorf("reflect Send 2, native recv %d", i);
+		}
+
+		// Recv
+		c <- 3;
+		if i := cv.Recv().(*IntValue).Get(); i != 3 {
+			t.Errorf("native send 3, reflect Recv %d", i);
+		}
+
+		// TryRecv fail
+		val := cv.TryRecv();
+		if val != nil {
+			t.Errorf("TryRecv on empty chan: %s", valueToString(val));
+		}
+
+		// TryRecv success
+		c <- 4;
+		val = cv.TryRecv();
+		if val == nil {
+			t.Errorf("TryRecv on ready chan got nil");
+		} else if i := val.(*IntValue).Get(); i != 4 {
+			t.Errorf("native send 4, TryRecv %d", i);
+		}
+
+		// TrySend fail
+		c <- 100;
+		ok := cv.TrySend(NewValue(5));
+		i := <-c;
+		if ok {
+			t.Errorf("TrySend on full chan succeeded: value %d", i);
+		}
+
+		// TrySend success
+		ok = cv.TrySend(NewValue(6));
+		if !ok {
+			t.Errorf("TrySend on empty chan failed");
+		} else {
+			if i = <-c; i != 6 {
+				t.Errorf("TrySend 6, recv %d", i);
+			}
+		}
+	}
+
+	// check creation of unbuffered channel
+	var c chan int;
+	cv := MakeChan(Typeof(c).(*ChanType), 0);
+	c = cv.Interface().(chan int);
+	if cv.TrySend(NewValue(7)) {
+		t.Errorf("TrySend on sync chan succeeded");
+	}
+	if cv.TryRecv() != nil {
+		t.Errorf("TryRecv on sync chan succeeded");
+	}
+}
+

src/pkg/reflect/value.go

@@ -631,26 +631,74 @@ func (v *ChanValue) Get() uintptr {
 	return *(*uintptr)(v.addr);
 }
 
+// implemented in ../pkg/runtime/reflect.cgo
+func makechan(typ *runtime.ChanType, size uint32) (ch *byte)
+func chansend(ch, val *byte, pres *bool)
+func chanrecv(ch, val *byte, pres *bool)
+
+// internal send; non-blocking if b != nil
+func (v *ChanValue) send(x Value, b *bool) {
+	t := v.Type().(*ChanType);
+	if t.Dir() & SendDir == 0{
+		panic("send on recv-only channel");
+	}
+	ch := *(**byte)(v.addr);
+	chansend(ch, (*byte)(x.getAddr()), b);
+}
+
+// internal recv; non-blocking if b != nil
+func (v *ChanValue) recv(b *bool) Value {
+	t := v.Type().(*ChanType);
+	if t.Dir() & RecvDir == 0 {
+		panic("recv on send-only channel");
+	}
+	ch := *(**byte)(v.addr);
+	newval := MakeZero(t.Elem());
+	x := MakeZero(t.Elem());
+	chanrecv(ch, (*byte)(x.getAddr()), b);
+	return x;
+}
+
 // Send sends x on the channel v.
 func (v *ChanValue) Send(x Value) {
-	panic("unimplemented: channel Send");
+	v.send(x, nil);
 }
 
 // Recv receives and returns a value from the channel v.
 func (v *ChanValue) Recv() Value {
-	panic("unimplemented: channel Receive");
+	return v.recv(nil);
 }
 
 // TrySend attempts to sends x on the channel v but will not block.
 // It returns true if the value was sent, false otherwise.
 func (v *ChanValue) TrySend(x Value) bool {
-	panic("unimplemented: channel TrySend");
+	var ok bool;
+	v.send(x, &ok);
+	return ok;
 }
 
 // TryRecv attempts to receive a value from the channel v but will not block.
 // It returns the value if one is received, nil otherwise.
 func (v *ChanValue) TryRecv() Value {
-	panic("unimplemented: channel TryRecv");
+	var ok bool;
+	x := v.recv(&ok);
+	if !ok {
+		return nil;
+	}
+	return x;
+}
+
+// MakeChan creates a new channel with the specified type and buffer size.
+func MakeChan(typ *ChanType, buffer int) *ChanValue {
+	if buffer < 0 {
+		panic("MakeChan: negative buffer size");
+	}
+	if typ.Dir() != BothDir {
+		panic("MakeChan: unidirectional channel type");
+	}
+	v := MakeZero(typ).(*ChanValue);
+	*(**byte)(v.addr) = makechan((*runtime.ChanType)(unsafe.Pointer(typ)), uint32(buffer));
+	return v;
 }
 
 /*
@@ -818,6 +866,7 @@ func (v *MapValue) Keys() []Value {
 	return a[0:i];
 }
 
+// MakeMap creates a new map of the specified type.
 func MakeMap(typ *MapType) *MapValue {
 	v := MakeZero(typ).(*MapValue);
 	*(**byte)(v.addr) = makemap((*runtime.MapType)(unsafe.Pointer(typ)));

src/pkg/runtime/chan.c

@@ -15,7 +15,6 @@ enum
 	Emax		= 0x0800,	// error limit before throw
 };
 
-typedef	struct	Hchan	Hchan;
 typedef	struct	Link	Link;
 typedef	struct	WaitQ	WaitQ;
 typedef	struct	SudoG	SudoG;
@@ -88,10 +87,8 @@ static	uint32	gcd(uint32, uint32);
 static	uint32	fastrand1(void);
 static	uint32	fastrand2(void);
 
-// newchan(elemsize uint32, elemalg uint32, hint uint32) (hchan *chan any);
-void
-sys·newchan(uint32 elemsize, uint32 elemalg, uint32 hint,
-	Hchan* ret)
+Hchan*
+makechan(uint32 elemsize, uint32 elemalg, uint32 hint)
 {
 	Hchan *c;
 	int32 i;
@@ -126,9 +123,6 @@ sys·newchan(uint32 elemsize, uint32 elemalg, uint32 hint,
 		c->dataqsiz = hint;
 	}
 
-	ret = c;
-	FLUSH(&ret);
-
 	if(debug) {
 		prints("newchan: chan=");
 		sys·printpointer(c);
@@ -140,6 +134,16 @@ sys·newchan(uint32 elemsize, uint32 elemalg, uint32 hint,
 		sys·printint(c->dataqsiz);
 		prints("\n");
 	}
+
+	return c;
+}
+
+// newchan(elemsize uint32, elemalg uint32, hint uint32) (hchan *chan any);
+void
+sys·newchan(uint32 elemsize, uint32 elemalg, uint32 hint, Hchan *ret)
+{
+	ret = makechan(elemsize, elemalg, hint);
+	FLUSH(&ret);
 }
 
 static void
@@ -162,7 +166,7 @@ incerr(Hchan* c)
  * not complete
  */
 void
-sendchan(Hchan *c, byte *ep, bool *pres)
+chansend(Hchan *c, byte *ep, bool *pres)
 {
 	SudoG *sg;
 	G* gp;
@@ -266,7 +270,7 @@ closed:
 	unlock(&chanlock);
 }
 
-static void
+void
 chanrecv(Hchan* c, byte *ep, bool* pres)
 {
 	SudoG *sg;
@@ -381,7 +385,7 @@ sys·chansend1(Hchan* c, ...)
 
 	o = rnd(sizeof(c), c->elemsize);
 	ae = (byte*)&c + o;
-	sendchan(c, ae, nil);
+	chansend(c, ae, nil);
 }
 
 // chansend2(hchan *chan any, elem any) (pres bool);
@@ -396,7 +400,7 @@ sys·chansend2(Hchan* c, ...)
 	o = rnd(o+c->elemsize, Structrnd);
 	ap = (byte*)&c + o;
 
-	sendchan(c, ae, ap);
+	chansend(c, ae, ap);
 }
 
 // chanrecv1(hchan *chan any) (elem any);

src/pkg/runtime/reflect.cgo

@@ -49,3 +49,27 @@ func makemap(typ *byte) (map *byte) {
 
 	map = (byte*)makemap(t->key->size, t->elem->size, t->key->alg, t->elem->alg, 0);
 }
+
+/*
+ * Go wrappers around the C functions in chan.c
+ */
+
+func makechan(typ *byte, size uint32) (ch *byte) {
+	ChanType *t;
+
+	// typ is a *runtime.ChanType, but the ChanType
+	// defined in type.h includes an interface value header
+	// in front of the raw ChanType.  the -2 below backs up
+	// to the interface value header.
+	t = (ChanType*)((void**)typ - 2);
+	ch = (byte*)makechan(t->elem->size, t->elem->alg, size);
+}
+
+func chansend(ch *byte, val *byte, pres *bool) {
+	chansend((Hchan*)ch, val, pres);
+}
+
+func chanrecv(ch *byte, val *byte, pres *bool) {
+	chanrecv((Hchan*)ch, val, pres);
+}
+

src/pkg/runtime/runtime.h

@@ -61,6 +61,7 @@ typedef	struct	Eface	Eface;
 typedef	struct	Type		Type;
 typedef	struct	Defer		Defer;
 typedef	struct	hash		Hmap;
+typedef	struct	Hchan		Hchan;
 
 /*
  * per cpu declaration
@@ -458,6 +459,7 @@ float64	ldexp(float64 d, int32 e);
 float64	modf(float64 d, float64 *ip);
 void	semacquire(uint32*);
 void	semrelease(uint32*);
+
 void	mapassign(Hmap*, byte*, byte*);
 void	mapaccess(Hmap*, byte*, byte*, bool*);
 struct hash_iter*	mapiterinit(Hmap*);
@@ -465,3 +467,7 @@ void	mapiternext(struct hash_iter*);
 bool	mapiterkey(struct hash_iter*, void*);
 void	mapiterkeyvalue(struct hash_iter*, void*, void*);
 Hmap*	makemap(uint32, uint32, uint32, uint32, uint32);
+
+Hchan*	makechan(uint32, uint32, uint32);
+void	chansend(Hchan*, void*, bool*);
+void	chanrecv(Hchan*, void*, bool*);

src/pkg/runtime/type.h

@@ -12,6 +12,7 @@ typedef struct InterfaceType InterfaceType;
 typedef struct Method Method;
 typedef struct IMethod IMethod;
 typedef struct MapType MapType;
+typedef struct ChanType ChanType;
 
 struct CommonType
 {
@@ -71,3 +72,10 @@ struct MapType
 	Type *key;
 	Type *elem;
 };
+
+struct ChanType
+{
+	Type;
+	Type *elem;
+	uintptr dir;
+};