mremap2 test

Author: anton-kuklin

unix/mremap_linux_test.go

@@ -27,5 +27,15 @@ func TestMremap2(t *testing.T) {
 		t.Fatalf("Msync: %v", err)
 	}
 
-	newB, err := unix.Mremap2(b, unix.Getpagesize())
+	bNew, err := unix.Mremap2(b, unix.Getpagesize(), unix.MREMAP_MAYMOVE)
+	if err != nil {
+		t.Fatalf("Mremap2: %v", err)
+	}
+
+	if bNew[0] != 42 {
+		t.Fatal("first element value was changed")
+	}
+	if len(bNew) != unix.Getpagesize() {
+		t.Fatal("first ")
+	}
 }

unix/syscall_unix.go

@@ -167,7 +167,9 @@ func (m *mmapper) Mremap(oldData []byte, newData []byte, flags int) (data []byte
 	bNew := unsafe.Slice((*byte)(unsafe.Pointer(newAddr)), len(newData))
 	pNew := &bNew[cap(bNew)-1]
 	m.active[pNew] = bNew
-	delete(m.active, pOld)
+	if flags&MREMAP_DONTUNMAP == 0 {
+		delete(m.active, pOld)
+	}
 	return bNew, nil
 }
 
@@ -190,7 +192,9 @@ func (m *mmapper) Mremap2(oldData []byte, newLength int, flags int) (data []byte
 	bNew := unsafe.Slice((*byte)(unsafe.Pointer(newAddr)), newLength)
 	pNew := &bNew[cap(bNew)-1]
 	m.active[pNew] = bNew
-	delete(m.active, pOld)
+	if flags&MREMAP_DONTUNMAP == 0 {
+		delete(m.active, pOld)
+	}
 	return bNew, nil
 }