mirror of
https://github.com/go-gitea/gitea.git
synced 2024-08-27 06:37:30 +02:00
281 lines
7.5 KiB
Go
281 lines
7.5 KiB
Go
|
// 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"
|
||
|
"runtime"
|
||
|
"unsafe"
|
||
|
)
|
||
|
|
||
|
var errNotImplemented = errors.New("not implemented on " + runtime.GOOS + "/" + runtime.GOARCH)
|
||
|
|
||
|
// 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)
|
||
|
}
|
||
|
|
||
|
// ControlMessageSpace returns the whole length of control message.
|
||
|
func ControlMessageSpace(dataLen int) int {
|
||
|
return controlMessageSpace(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)
|
||
|
}
|