cat: Fix go routine leak

This commit is contained in:
Nick Craig-Wood 2017-02-09 11:25:36 +00:00
parent c0ad29c06c
commit dd20a297d6

View file

@ -5,7 +5,6 @@ package fs
import (
"fmt"
"io"
"io/ioutil"
"log"
"mime"
"path"
@ -1236,6 +1235,17 @@ func CleanUp(f Fs) error {
return doCleanUp()
}
// wrap a Reader and a Closer together into a ReadCloser
type readCloser struct {
io.Reader
Closer io.Closer
}
// Close the Closer
func (r *readCloser) Close() error {
return r.Closer.Close()
}
// Cat any files to the io.Writer
//
// if offset == 0 it will be ignored
@ -1266,10 +1276,10 @@ func Cat(f Fs, w io.Writer, offset, count int64) error {
ErrorLog(o, "Failed to open: %v", err)
return
}
reader := in
if count >= 0 {
reader = ioutil.NopCloser(&io.LimitedReader{R: in, N: count})
in = &readCloser{Reader: &io.LimitedReader{R: in, N: count}, Closer: in}
}
in = NewAccountWithBuffer(in, o) // account and buffer the transfer
defer func() {
err = in.Close()
if err != nil {
@ -1277,11 +1287,10 @@ func Cat(f Fs, w io.Writer, offset, count int64) error {
ErrorLog(o, "Failed to close: %v", err)
}
}()
inAccounted := NewAccountWithBuffer(reader, o) // account and buffer the transfer
// take the lock just before we output stuff, so at the last possible moment
mu.Lock()
defer mu.Unlock()
_, err = io.Copy(w, inAccounted)
_, err = io.Copy(w, in)
if err != nil {
Stats.Error()
ErrorLog(o, "Failed to send to output: %v", err)