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
|
/*
* Copyright (c) 2014 by Farsight Security, Inc.
*
* 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 dnstap
import (
"bufio"
"io"
"log"
"os"
"github.com/golang/protobuf/proto"
)
type TextFormatFunc func(*Dnstap) ([]byte, bool)
type TextOutput struct {
format TextFormatFunc
outputChannel chan []byte
wait chan bool
writer *bufio.Writer
}
func NewTextOutput(writer io.Writer, format TextFormatFunc) (o *TextOutput) {
o = new(TextOutput)
o.format = format
o.outputChannel = make(chan []byte, outputChannelSize)
o.writer = bufio.NewWriter(writer)
o.wait = make(chan bool)
return
}
func NewTextOutputFromFilename(fname string, format TextFormatFunc) (o *TextOutput, err error) {
if fname == "" || fname == "-" {
return NewTextOutput(os.Stdout, format), nil
}
writer, err := os.Create(fname)
if err != nil {
return
}
return NewTextOutput(writer, format), nil
}
func (o *TextOutput) GetOutputChannel() chan []byte {
return o.outputChannel
}
func (o *TextOutput) RunOutputLoop() {
dt := &Dnstap{}
for frame := range o.outputChannel {
if err := proto.Unmarshal(frame, dt); err != nil {
log.Fatalf("dnstap.TextOutput: proto.Unmarshal() failed: %s\n", err)
break
}
buf, ok := o.format(dt)
if !ok {
log.Fatalf("dnstap.TextOutput: text format function failed\n")
break
}
if _, err := o.writer.Write(buf); err != nil {
log.Fatalf("dnstap.TextOutput: write failed: %s\n", err)
break
}
o.writer.Flush()
}
close(o.wait)
}
func (o *TextOutput) Close() {
close(o.outputChannel)
<-o.wait
o.writer.Flush()
}
|
