-
Notifications
You must be signed in to change notification settings - Fork 349
/
timeout_reader.go
87 lines (79 loc) · 1.8 KB
/
timeout_reader.go
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
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
// Copyright 2021 iLogtail Authors
//
// 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 util
import (
"bufio"
"errors"
"fmt"
"io"
"runtime"
"time"
)
const BufferSize = 4096
var ErrReaderTimeout = errors.New("timeout")
type TimeoutReader struct {
b *bufio.Reader
t time.Duration
ch <-chan error
}
func NewTimeoutReader(r io.Reader, to time.Duration) *TimeoutReader {
return &TimeoutReader{b: bufio.NewReaderSize(r, BufferSize), t: to}
}
func (r *TimeoutReader) Read(b []byte) (n int, err error) {
if r.ch == nil {
if r.t < 0 || r.b.Buffered() > 0 {
return r.b.Read(b)
}
ch := make(chan error, 1)
r.ch = ch
go func() {
_, err = r.b.Peek(1)
ch <- err
}()
runtime.Gosched()
}
if r.t < 0 {
err = <-r.ch // Block
} else {
select {
case err = <-r.ch: // Poll
default:
if r.t == 0 {
return 0, ErrReaderTimeout
}
select {
case err = <-r.ch: // Timeout
case <-time.After(r.t):
return 0, ErrReaderTimeout
}
}
}
r.ch = nil
if r.b.Buffered() > 0 {
n, _ = r.b.Read(b)
}
return
}
func DoFuncWithTimeout(timeout time.Duration, workFunc func() error) error {
ch := make(chan error, 1)
go func() {
ch <- workFunc()
}()
select {
case err := <-ch:
return err
case <-time.After(timeout):
return fmt.Errorf("operation timed out after %v", timeout)
}
}