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| // 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 (
| "internal/poll"
| "io"
| "os"
| )
|
| // sendFile copies the contents of r to c using the sendfile
| // 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.
| func sendFile(c *netFD, r io.Reader) (written int64, err error, handled bool) {
| var remain int64 = 1 << 62 // by default, copy until EOF
|
| lr, ok := r.(*io.LimitedReader)
| if ok {
| remain, r = lr.N, lr.R
| if remain <= 0 {
| return 0, nil, true
| }
| }
| f, ok := r.(*os.File)
| if !ok {
| return 0, nil, false
| }
|
| sc, err := f.SyscallConn()
| if err != nil {
| return 0, nil, false
| }
|
| var werr error
| err = sc.Read(func(fd uintptr) bool {
| written, werr = poll.SendFile(&c.pfd, int(fd), remain)
| return true
| })
| if werr == nil {
| werr = err
| }
|
| if lr != nil {
| lr.N = remain - written
| }
| return written, wrapSyscallError("sendfile", err), written > 0
| }
|
|
