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-rw-r--r--vendor/golang.org/x/net/internal/socket/socket.go285
1 files changed, 285 insertions, 0 deletions
diff --git a/vendor/golang.org/x/net/internal/socket/socket.go b/vendor/golang.org/x/net/internal/socket/socket.go
new file mode 100644
index 0000000..5f9730e
--- /dev/null
+++ b/vendor/golang.org/x/net/internal/socket/socket.go
@@ -0,0 +1,285 @@
+// 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.
+
+// Package socket provides a portable interface for socket system
+// calls.
+package socket // import "golang.org/x/net/internal/socket"
+
+import (
+ "errors"
+ "net"
+ "unsafe"
+)
+
+// An Option represents a sticky socket option.
+type Option struct {
+ Level int // level
+ Name int // name; must be equal or greater than 1
+ Len int // length of value in bytes; must be equal or greater than 1
+}
+
+// Get reads a value for the option from the kernel.
+// It returns the number of bytes written into b.
+func (o *Option) Get(c *Conn, b []byte) (int, error) {
+ if o.Name < 1 || o.Len < 1 {
+ return 0, errors.New("invalid option")
+ }
+ if len(b) < o.Len {
+ return 0, errors.New("short buffer")
+ }
+ return o.get(c, b)
+}
+
+// GetInt returns an integer value for the option.
+//
+// The Len field of Option must be either 1 or 4.
+func (o *Option) GetInt(c *Conn) (int, error) {
+ if o.Len != 1 && o.Len != 4 {
+ return 0, errors.New("invalid option")
+ }
+ var b []byte
+ var bb [4]byte
+ if o.Len == 1 {
+ b = bb[:1]
+ } else {
+ b = bb[:4]
+ }
+ n, err := o.get(c, b)
+ if err != nil {
+ return 0, err
+ }
+ if n != o.Len {
+ return 0, errors.New("invalid option length")
+ }
+ if o.Len == 1 {
+ return int(b[0]), nil
+ }
+ return int(NativeEndian.Uint32(b[:4])), nil
+}
+
+// Set writes the option and value to the kernel.
+func (o *Option) Set(c *Conn, b []byte) error {
+ if o.Name < 1 || o.Len < 1 {
+ return errors.New("invalid option")
+ }
+ if len(b) < o.Len {
+ return errors.New("short buffer")
+ }
+ return o.set(c, b)
+}
+
+// SetInt writes the option and value to the kernel.
+//
+// The Len field of Option must be either 1 or 4.
+func (o *Option) SetInt(c *Conn, v int) error {
+ if o.Len != 1 && o.Len != 4 {
+ return errors.New("invalid option")
+ }
+ var b []byte
+ if o.Len == 1 {
+ b = []byte{byte(v)}
+ } else {
+ var bb [4]byte
+ NativeEndian.PutUint32(bb[:o.Len], uint32(v))
+ b = bb[:4]
+ }
+ return o.set(c, b)
+}
+
+func controlHeaderLen() int {
+ return roundup(sizeofCmsghdr)
+}
+
+func controlMessageLen(dataLen int) int {
+ return roundup(sizeofCmsghdr) + dataLen
+}
+
+// ControlMessageSpace returns the whole length of control message.
+func ControlMessageSpace(dataLen int) int {
+ return roundup(sizeofCmsghdr) + roundup(dataLen)
+}
+
+// A ControlMessage represents the head message in a stream of control
+// messages.
+//
+// A control message comprises of a header, data and a few padding
+// fields to conform to the interface to the kernel.
+//
+// See RFC 3542 for further information.
+type ControlMessage []byte
+
+// Data returns the data field of the control message at the head on
+// m.
+func (m ControlMessage) Data(dataLen int) []byte {
+ l := controlHeaderLen()
+ if len(m) < l || len(m) < l+dataLen {
+ return nil
+ }
+ return m[l : l+dataLen]
+}
+
+// Next returns the control message at the next on m.
+//
+// Next works only for standard control messages.
+func (m ControlMessage) Next(dataLen int) ControlMessage {
+ l := ControlMessageSpace(dataLen)
+ if len(m) < l {
+ return nil
+ }
+ return m[l:]
+}
+
+// MarshalHeader marshals the header fields of the control message at
+// the head on m.
+func (m ControlMessage) MarshalHeader(lvl, typ, dataLen int) error {
+ if len(m) < controlHeaderLen() {
+ return errors.New("short message")
+ }
+ h := (*cmsghdr)(unsafe.Pointer(&m[0]))
+ h.set(controlMessageLen(dataLen), lvl, typ)
+ return nil
+}
+
+// ParseHeader parses and returns the header fields of the control
+// message at the head on m.
+func (m ControlMessage) ParseHeader() (lvl, typ, dataLen int, err error) {
+ l := controlHeaderLen()
+ if len(m) < l {
+ return 0, 0, 0, errors.New("short message")
+ }
+ h := (*cmsghdr)(unsafe.Pointer(&m[0]))
+ return h.lvl(), h.typ(), int(uint64(h.len()) - uint64(l)), nil
+}
+
+// Marshal marshals the control message at the head on m, and returns
+// the next control message.
+func (m ControlMessage) Marshal(lvl, typ int, data []byte) (ControlMessage, error) {
+ l := len(data)
+ if len(m) < ControlMessageSpace(l) {
+ return nil, errors.New("short message")
+ }
+ h := (*cmsghdr)(unsafe.Pointer(&m[0]))
+ h.set(controlMessageLen(l), lvl, typ)
+ if l > 0 {
+ copy(m.Data(l), data)
+ }
+ return m.Next(l), nil
+}
+
+// Parse parses m as a single or multiple control messages.
+//
+// Parse works for both standard and compatible messages.
+func (m ControlMessage) Parse() ([]ControlMessage, error) {
+ var ms []ControlMessage
+ for len(m) >= controlHeaderLen() {
+ h := (*cmsghdr)(unsafe.Pointer(&m[0]))
+ l := h.len()
+ if l <= 0 {
+ return nil, errors.New("invalid header length")
+ }
+ if uint64(l) < uint64(controlHeaderLen()) {
+ return nil, errors.New("invalid message length")
+ }
+ if uint64(l) > uint64(len(m)) {
+ return nil, errors.New("short buffer")
+ }
+ // On message reception:
+ //
+ // |<- ControlMessageSpace --------------->|
+ // |<- controlMessageLen ---------->| |
+ // |<- controlHeaderLen ->| | |
+ // +---------------+------+---------+------+
+ // | Header | PadH | Data | PadD |
+ // +---------------+------+---------+------+
+ //
+ // On compatible message reception:
+ //
+ // | ... |<- controlMessageLen ----------->|
+ // | ... |<- controlHeaderLen ->| |
+ // +-----+---------------+------+----------+
+ // | ... | Header | PadH | Data |
+ // +-----+---------------+------+----------+
+ ms = append(ms, ControlMessage(m[:l]))
+ ll := l - controlHeaderLen()
+ if len(m) >= ControlMessageSpace(ll) {
+ m = m[ControlMessageSpace(ll):]
+ } else {
+ m = m[controlMessageLen(ll):]
+ }
+ }
+ return ms, nil
+}
+
+// NewControlMessage returns a new stream of control messages.
+func NewControlMessage(dataLen []int) ControlMessage {
+ var l int
+ for i := range dataLen {
+ l += ControlMessageSpace(dataLen[i])
+ }
+ return make([]byte, l)
+}
+
+// A Message represents an IO message.
+type Message struct {
+ // 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.
+ Buffers [][]byte
+
+ // OOB contains protocol-specific control or miscellaneous
+ // ancillary data known as out-of-band data.
+ OOB []byte
+
+ // Addr specifies a destination address when writing.
+ // It can be nil when the underlying protocol of the raw
+ // connection uses connection-oriented communication.
+ // After a successful read, it may contain the source address
+ // on the received packet.
+ Addr net.Addr
+
+ N int // # of bytes read or written from/to Buffers
+ NN int // # of bytes read or written from/to OOB
+ Flags int // protocol-specific information on the received message
+}
+
+// RecvMsg wraps recvmsg system call.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_PEEK.
+func (c *Conn) RecvMsg(m *Message, flags int) error {
+ return c.recvMsg(m, flags)
+}
+
+// SendMsg wraps sendmsg system call.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_DONTROUTE.
+func (c *Conn) SendMsg(m *Message, flags int) error {
+ return c.sendMsg(m, flags)
+}
+
+// RecvMsgs wraps recvmmsg system call.
+//
+// It returns the number of processed messages.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_PEEK.
+//
+// Only Linux supports this.
+func (c *Conn) RecvMsgs(ms []Message, flags int) (int, error) {
+ return c.recvMsgs(ms, flags)
+}
+
+// SendMsgs wraps sendmmsg system call.
+//
+// It returns the number of processed messages.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_DONTROUTE.
+//
+// Only Linux supports this.
+func (c *Conn) SendMsgs(ms []Message, flags int) (int, error) {
+ return c.sendMsgs(ms, flags)
+}