--- /dev/null
+// Copyright 2017 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.
+
+// +build go1.9
+
+package ipv4
+
+import (
+ "net"
+ "runtime"
+ "syscall"
+
+ "golang.org/x/net/internal/socket"
+)
+
+// BUG(mikio): On Windows, the ReadBatch and WriteBatch methods of
+// PacketConn are not implemented.
+
+// BUG(mikio): On Windows, the ReadBatch and WriteBatch methods of
+// RawConn are not implemented.
+
+// A Message represents an IO message.
+//
+// type Message struct {
+// Buffers [][]byte
+// OOB []byte
+// Addr net.Addr
+// N int
+// NN int
+// Flags int
+// }
+//
+// The Buffers fields represents a list of contiguous buffers, which
+// can be used for vectored IO, for example, putting a header and a
+// payload in each slice.
+// When writing, the Buffers field must contain at least one byte to
+// write.
+// When reading, the Buffers field will always contain a byte to read.
+//
+// The OOB field contains protocol-specific control or miscellaneous
+// ancillary data known as out-of-band data.
+// It can be nil when not required.
+//
+// The Addr field specifies a destination address when writing.
+// It can be nil when the underlying protocol of the endpoint uses
+// connection-oriented communication.
+// After a successful read, it may contain the source address on the
+// received packet.
+//
+// The N field indicates the number of bytes read or written from/to
+// Buffers.
+//
+// The NN field indicates the number of bytes read or written from/to
+// OOB.
+//
+// The Flags field contains protocol-specific information on the
+// received message.
+type Message = socket.Message
+
+// ReadBatch reads a batch of messages.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_PEEK.
+//
+// On a successful read it returns the number of messages received, up
+// to len(ms).
+//
+// On Linux, a batch read will be optimized.
+// On other platforms, this method will read only a single message.
+//
+// Unlike the ReadFrom method, it doesn't strip the IPv4 header
+// followed by option headers from the received IPv4 datagram when the
+// underlying transport is net.IPConn. Each Buffers field of Message
+// must be large enough to accommodate an IPv4 header and option
+// headers.
+func (c *payloadHandler) ReadBatch(ms []Message, flags int) (int, error) {
+ if !c.ok() {
+ return 0, syscall.EINVAL
+ }
+ switch runtime.GOOS {
+ case "linux":
+ n, err := c.RecvMsgs([]socket.Message(ms), flags)
+ if err != nil {
+ err = &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+ }
+ return n, err
+ default:
+ n := 1
+ err := c.RecvMsg(&ms[0], flags)
+ if err != nil {
+ n = 0
+ err = &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+ }
+ return n, err
+ }
+}
+
+// WriteBatch writes a batch of messages.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_DONTROUTE.
+//
+// It returns the number of messages written on a successful write.
+//
+// On Linux, a batch write will be optimized.
+// On other platforms, this method will write only a single message.
+func (c *payloadHandler) WriteBatch(ms []Message, flags int) (int, error) {
+ if !c.ok() {
+ return 0, syscall.EINVAL
+ }
+ switch runtime.GOOS {
+ case "linux":
+ n, err := c.SendMsgs([]socket.Message(ms), flags)
+ if err != nil {
+ err = &net.OpError{Op: "write", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+ }
+ return n, err
+ default:
+ n := 1
+ err := c.SendMsg(&ms[0], flags)
+ if err != nil {
+ n = 0
+ err = &net.OpError{Op: "write", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+ }
+ return n, err
+ }
+}
+
+// ReadBatch reads a batch of messages.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_PEEK.
+//
+// On a successful read it returns the number of messages received, up
+// to len(ms).
+//
+// On Linux, a batch read will be optimized.
+// On other platforms, this method will read only a single message.
+func (c *packetHandler) ReadBatch(ms []Message, flags int) (int, error) {
+ if !c.ok() {
+ return 0, syscall.EINVAL
+ }
+ switch runtime.GOOS {
+ case "linux":
+ n, err := c.RecvMsgs([]socket.Message(ms), flags)
+ if err != nil {
+ err = &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+ }
+ return n, err
+ default:
+ n := 1
+ err := c.RecvMsg(&ms[0], flags)
+ if err != nil {
+ n = 0
+ err = &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+ }
+ return n, err
+ }
+}
+
+// WriteBatch writes a batch of messages.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_DONTROUTE.
+//
+// It returns the number of messages written on a successful write.
+//
+// On Linux, a batch write will be optimized.
+// On other platforms, this method will write only a single message.
+func (c *packetHandler) WriteBatch(ms []Message, flags int) (int, error) {
+ if !c.ok() {
+ return 0, syscall.EINVAL
+ }
+ switch runtime.GOOS {
+ case "linux":
+ n, err := c.SendMsgs([]socket.Message(ms), flags)
+ if err != nil {
+ err = &net.OpError{Op: "write", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+ }
+ return n, err
+ default:
+ n := 1
+ err := c.SendMsg(&ms[0], flags)
+ if err != nil {
+ n = 0
+ err = &net.OpError{Op: "write", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+ }
+ return n, err
+ }
+}
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