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Index: gcc-6-6.2.1-4.1/src/libgo/go/net/sendfile_gnu.go
===================================================================
--- /dev/null
+++ gcc-6-6.2.1-4.1/src/libgo/go/net/sendfile_gnu.go
@@ -0,0 +1,79 @@
+// 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"
+)
+
+// maxSendfileSize is the largest chunk size we ask the kernel to copy
+// at a time.
+const maxSendfileSize int = 4 << 20
+
+// 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
+ }
+
+ if err := c.writeLock(); err != nil {
+ return 0, err, true
+ }
+ defer c.writeUnlock()
+
+ dst := c.sysfd
+ src := int(f.Fd())
+ for remain > 0 {
+ n := maxSendfileSize
+ if int64(n) > remain {
+ n = int(remain)
+ }
+ n, err1 := syscall.Sendfile(dst, src, nil, n)
+ if n > 0 {
+ written += int64(n)
+ remain -= int64(n)
+ }
+ if n == 0 && err1 == nil {
+ break
+ }
+ if err1 == syscall.EAGAIN {
+ if err1 = c.pd.WaitWrite(); err1 == nil {
+ continue
+ }
+ }
+ if err1 != nil {
+ // This includes syscall.ENOSYS (no kernel
+ // support) and syscall.EINVAL (fd types which
+ // don't implement sendfile)
+ err = err1
+ break
+ }
+ }
+ if lr != nil {
+ lr.N = remain
+ }
+ if err != nil {
+ err = os.NewSyscallError("sendfile", err)
+ }
+ return written, err, written > 0
+}
|
