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
|
package packfile
import (
"bufio"
"fmt"
"io"
)
type trackingReader struct {
r io.Reader
position int64
}
func NewTrackingReader(r io.Reader) *trackingReader {
return &trackingReader{
r: bufio.NewReader(r),
}
}
func (t *trackingReader) Read(p []byte) (n int, err error) {
n, err = t.r.Read(p)
if err != nil {
return 0, err
}
t.position += int64(n)
return n, err
}
func (t *trackingReader) ReadByte() (c byte, err error) {
var p [1]byte
n, err := t.r.Read(p[:])
if err != nil {
return 0, err
}
if n > 1 {
return 0, fmt.Errorf("read %d bytes, should have read just 1", n)
}
t.position++
return p[0], nil
}
// close is used with defer to close the given io.Closer and check its
// returned error value. If Close returns an error and the given *error
// is not nil, *error is set to the error returned by Close.
//
// close is typically used with named return values like so:
//
// func do(obj *Object) (err error) {
// w, err := obj.Writer()
// if err != nil {
// return nil
// }
// defer close(w, &err)
// // work with w
// }
func close(c io.Closer, err *error) {
if cerr := c.Close(); cerr != nil && *err == nil {
*err = cerr
}
}
|
