image/jpeg: Decode errors reading from the network

[bradfitz]

The following program sometimes fails (with jpeg.errMissingFF00) and sometimes succeeds:

package main

import (
    "image/jpeg"
    "log"
    "net/http"
)

func main() {
    res, err := http.Get("https://blog.golang.org/go-programming-language-turns-two_gophers.jpg";)
    if err != nil {
        log.Fatal(err)
    }
    if res.StatusCode != 200 {
        log.Fatal(res.Status)
    }
    if _, err := jpeg.Decode(res.Body); err != nil {
        log.Fatal(err)
    }
}

It depends on timing & how the network packets arrive.

The errors and intermixed successes:

mac:~ bradfitz$ go run d.go
2014/11/18 18:00:19 invalid JPEG format: missing 0xff00 sequence
exit status 1
mac:~ bradfitz$ go run d.go
2014/11/18 18:00:20 invalid JPEG format: missing 0xff00 sequence
exit status 1
mac:~ bradfitz$ go run d.go
mac:~ bradfitz$ go run d.go
2014/11/18 18:00:23 invalid JPEG format: missing 0xff00 sequence
exit status 1
mac:~ bradfitz$ go run d.go
2014/11/18 18:00:24 invalid JPEG format: missing 0xff00 sequence
exit status 1
mac:~ bradfitz$ go run d.go
mac:~ bradfitz$ go run d.go
mac:~ bradfitz$ go run d.go
2014/11/18 18:00:28 invalid JPEG format: missing 0xff00 sequence
exit status 1
mac:~ bradfitz$ go run d.go
2014/11/18 18:00:30 invalid JPEG format: missing 0xff00 sequence
exit status 1
mac:~ bradfitz$ go run d.go
2014/11/18 18:00:31 invalid JPEG format: missing 0xff00 sequence
exit status 1

I suspect a problem with the interaction between the jpeg package's buffering and its
huffman reader.

[gopherbot]

Comment 1:

CL https://golang.org/cl/178120043 mentions this issue.

[rsc]

Comment 2:

This issue was closed by revision 0492304.

Status changed to Fixed.

[rsc]

Comment 3:

This issue was closed by revision 926c82fb5dad.

[rsc]

This was fixed in Go 1.4.