blob: ee7ff8b98c2d9849f4905610d22a13d3955a9c81 [file] [log] [blame]
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package net
import (
"io"
"os"
"syscall"
)
type sendfileOp struct {
anOp
src syscall.Handle // source
n uint32
}
func (o *sendfileOp) Submit() (err error) {
return syscall.TransmitFile(o.fd.sysfd, o.src, o.n, 0, &o.o, nil, syscall.TF_WRITE_BEHIND)
}
func (o *sendfileOp) Name() string {
return "TransmitFile"
}
// sendFile copies the contents of r to c using the TransmitFile
// system call to minimize copies.
//
// if handled == true, sendFile returns the number of bytes copied and any
// non-EOF error.
//
// if handled == false, sendFile performed no work.
//
// Note that sendfile for windows does not suppport >2GB file.
func sendFile(c *netFD, r io.Reader) (written int64, err error, handled bool) {
var n int64 = 0 // by default, copy until EOF
lr, ok := r.(*io.LimitedReader)
if ok {
n, r = lr.N, lr.R
if n <= 0 {
return 0, nil, true
}
}
f, ok := r.(*os.File)
if !ok {
return 0, nil, false
}
c.wio.Lock()
defer c.wio.Unlock()
c.incref()
defer c.decref()
var o sendfileOp
o.Init(c, 'w')
o.n = uint32(n)
o.src = f.Fd()
done, err := iosrv.ExecIO(&o, 0)
if err != nil {
return 0, err, false
}
if lr != nil {
lr.N -= int64(done)
}
return int64(done), nil, true
}