1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
// Copyright 2009 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 darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows
package net
import (
"context"
"errors"
"os"
"syscall"
)
func unixSocket(ctx context.Context, net string, laddr, raddr sockaddr, mode string) (*netFD, error) {
var sotype int
switch net {
case "unix":
sotype = syscall.SOCK_STREAM
case "unixgram":
sotype = syscall.SOCK_DGRAM
case "unixpacket":
sotype = syscall.SOCK_SEQPACKET
default:
return nil, UnknownNetworkError(net)
}
switch mode {
case "dial":
if laddr != nil && laddr.isWildcard() {
laddr = nil
}
if raddr != nil && raddr.isWildcard() {
raddr = nil
}
if raddr == nil && (sotype != syscall.SOCK_DGRAM || laddr == nil) {
return nil, errMissingAddress
}
case "listen":
default:
return nil, errors.New("unknown mode: " + mode)
}
fd, err := socket(ctx, net, syscall.AF_UNIX, sotype, 0, false, laddr, raddr)
if err != nil {
return nil, err
}
return fd, nil
}
func sockaddrToUnix(sa syscall.Sockaddr) Addr {
if s, ok := sa.(*syscall.SockaddrUnix); ok {
return &UnixAddr{Name: s.Name, Net: "unix"}
}
return nil
}
func sockaddrToUnixgram(sa syscall.Sockaddr) Addr {
if s, ok := sa.(*syscall.SockaddrUnix); ok {
return &UnixAddr{Name: s.Name, Net: "unixgram"}
}
return nil
}
func sockaddrToUnixpacket(sa syscall.Sockaddr) Addr {
if s, ok := sa.(*syscall.SockaddrUnix); ok {
return &UnixAddr{Name: s.Name, Net: "unixpacket"}
}
return nil
}
func sotypeToNet(sotype int) string {
switch sotype {
case syscall.SOCK_STREAM:
return "unix"
case syscall.SOCK_DGRAM:
return "unixgram"
case syscall.SOCK_SEQPACKET:
return "unixpacket"
default:
panic("sotypeToNet unknown socket type")
}
}
func (a *UnixAddr) family() int {
return syscall.AF_UNIX
}
func (a *UnixAddr) sockaddr(family int) (syscall.Sockaddr, error) {
if a == nil {
return nil, nil
}
return &syscall.SockaddrUnix{Name: a.Name}, nil
}
func (a *UnixAddr) toLocal(net string) sockaddr {
return a
}
func (c *UnixConn) readFrom(b []byte) (int, *UnixAddr, error) {
var addr *UnixAddr
n, sa, err := c.fd.readFrom(b)
switch sa := sa.(type) {
case *syscall.SockaddrUnix:
if sa.Name != "" {
addr = &UnixAddr{Name: sa.Name, Net: sotypeToNet(c.fd.sotype)}
}
}
return n, addr, err
}
func (c *UnixConn) readMsg(b, oob []byte) (n, oobn, flags int, addr *UnixAddr, err error) {
var sa syscall.Sockaddr
n, oobn, flags, sa, err = c.fd.readMsg(b, oob)
switch sa := sa.(type) {
case *syscall.SockaddrUnix:
if sa.Name != "" {
addr = &UnixAddr{Name: sa.Name, Net: sotypeToNet(c.fd.sotype)}
}
}
return
}
func (c *UnixConn) writeTo(b []byte, addr *UnixAddr) (int, error) {
if c.fd.isConnected {
return 0, ErrWriteToConnected
}
if addr == nil {
return 0, errMissingAddress
}
if addr.Net != sotypeToNet(c.fd.sotype) {
return 0, syscall.EAFNOSUPPORT
}
sa := &syscall.SockaddrUnix{Name: addr.Name}
return c.fd.writeTo(b, sa)
}
func (c *UnixConn) writeMsg(b, oob []byte, addr *UnixAddr) (n, oobn int, err error) {
if c.fd.sotype == syscall.SOCK_DGRAM && c.fd.isConnected {
return 0, 0, ErrWriteToConnected
}
var sa syscall.Sockaddr
if addr != nil {
if addr.Net != sotypeToNet(c.fd.sotype) {
return 0, 0, syscall.EAFNOSUPPORT
}
sa = &syscall.SockaddrUnix{Name: addr.Name}
}
return c.fd.writeMsg(b, oob, sa)
}
func dialUnix(ctx context.Context, net string, laddr, raddr *UnixAddr) (*UnixConn, error) {
fd, err := unixSocket(ctx, net, laddr, raddr, "dial")
if err != nil {
return nil, err
}
return newUnixConn(fd), nil
}
func (ln *UnixListener) accept() (*UnixConn, error) {
fd, err := ln.fd.accept()
if err != nil {
return nil, err
}
return newUnixConn(fd), nil
}
func (ln *UnixListener) close() error {
// The operating system doesn't clean up
// the file that announcing created, so
// we have to clean it up ourselves.
// There's a race here--we can't know for
// sure whether someone else has come along
// and replaced our socket name already--
// but this sequence (remove then close)
// is at least compatible with the auto-remove
// sequence in ListenUnix. It's only non-Go
// programs that can mess us up.
// Even if there are racy calls to Close, we want to unlink only for the first one.
ln.unlinkOnce.Do(func() {
if ln.path[0] != '@' && ln.unlink {
syscall.Unlink(ln.path)
}
})
return ln.fd.Close()
}
func (ln *UnixListener) file() (*os.File, error) {
f, err := ln.fd.dup()
if err != nil {
return nil, err
}
return f, nil
}
// SetUnlinkOnClose sets whether the underlying socket file should be removed
// from the file system when the listener is closed.
//
// The default behavior is to unlink the socket file only when package net created it.
// That is, when the listener and the underlying socket file were created by a call to
// Listen or ListenUnix, then by default closing the listener will remove the socket file.
// but if the listener was created by a call to FileListener to use an already existing
// socket file, then by default closing the listener will not remove the socket file.
func (l *UnixListener) SetUnlinkOnClose(unlink bool) {
l.unlink = unlink
}
func listenUnix(ctx context.Context, network string, laddr *UnixAddr) (*UnixListener, error) {
fd, err := unixSocket(ctx, network, laddr, nil, "listen")
if err != nil {
return nil, err
}
return &UnixListener{fd: fd, path: fd.laddr.String(), unlink: true}, nil
}
func listenUnixgram(ctx context.Context, network string, laddr *UnixAddr) (*UnixConn, error) {
fd, err := unixSocket(ctx, network, laddr, nil, "listen")
if err != nil {
return nil, err
}
return newUnixConn(fd), nil
}
|
