1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
// Copyright 2018 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package tcp
import (
"gvisor.googlesource.com/gvisor/pkg/tcpip/buffer"
)
// saveData is invoked by stateify.
func (s *segment) saveData() buffer.VectorisedView {
// We cannot save s.data directly as s.data.views may alias to s.views,
// which is not allowed by state framework (in-struct pointer).
v := make([]buffer.View, len(s.data.Views()))
// For views already delivered, we cannot save them directly as they may
// have already been sliced and saved elsewhere (e.g., readViews).
for i := 0; i < s.viewToDeliver; i++ {
v[i] = append([]byte(nil), s.data.Views()[i]...)
}
for i := s.viewToDeliver; i < len(v); i++ {
v[i] = s.data.Views()[i]
}
return buffer.NewVectorisedView(s.data.Size(), v)
}
// loadData is invoked by stateify.
func (s *segment) loadData(data buffer.VectorisedView) {
// NOTE: We cannot do the s.data = data.Clone(s.views[:]) optimization
// here because data.views is not guaranteed to be loaded by now. Plus,
// data.views will be allocated anyway so there really is little point
// of utilizing s.views for data.views.
s.data = data
}
// saveOptions is invoked by stateify.
func (s *segment) saveOptions() []byte {
// We cannot save s.options directly as it may point to s.data's trimmed
// tail, which is not allowed by state framework (in-struct pointer).
b := make([]byte, 0, cap(s.options))
return append(b, s.options...)
}
// loadOptions is invoked by stateify.
func (s *segment) loadOptions(options []byte) {
// NOTE: We cannot point s.options back into s.data's trimmed tail. But
// it is OK as they do not need to aliased. Plus, options is already
// allocated so there is no cost here.
s.options = options
}
|
