gcc/libgo/go/net/splice_linux.go
Ian Lance Taylor 4f4a855d82 libgo: update to Go1.12beta2
Reviewed-on: https://go-review.googlesource.com/c/158019

gotools/:
	* Makefile.am (go_cmd_vet_files): Update for Go1.12beta2 release.
	(GOTOOLS_TEST_TIMEOUT): Increase to 600.
	(check-runtime): Export LD_LIBRARY_PATH before computing GOARCH
	and GOOS.
	(check-vet): Copy golang.org/x/tools into check-vet-dir.
	* Makefile.in: Regenerate.

gcc/testsuite/:
	* go.go-torture/execute/names-1.go: Stop using debug/xcoff, which
	is no longer externally visible.

From-SVN: r268084
2019-01-18 19:04:36 +00:00

45 lines
1.1 KiB
Go

// Copyright 2018 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"
)
// splice transfers data from r to c using the splice system call to minimize
// copies from and to userspace. c must be a TCP connection. Currently, splice
// is only enabled if r is a TCP or a stream-oriented Unix connection.
//
// If splice returns handled == false, it has performed no work.
func splice(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
}
}
var s *netFD
if tc, ok := r.(*TCPConn); ok {
s = tc.fd
} else if uc, ok := r.(*UnixConn); ok {
if uc.fd.net != "unix" {
return 0, nil, false
}
s = uc.fd
} else {
return 0, nil, false
}
written, handled, sc, err := poll.Splice(&c.pfd, &s.pfd, remain)
if lr != nil {
lr.N -= written
}
return written, wrapSyscallError(sc, err), handled
}