| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
| 2 | |
| 3 | package socket |
| 4 | |
| 5 | import ( |
| 6 | "bufio" |
| 7 | "context" |
| 8 | "errors" |
| 9 | "fmt" |
| 10 | "net" |
| 11 | "os" |
| 12 | "sync" |
| 13 | "time" |
| 14 | ) |
| 15 | |
| 16 | func newTCPServer(addr string) *tcpServer { |
| 17 | ctx, cancel := context.WithCancel(context.Background()) |
| 18 | _, addr = parseAddress(addr) |
| 19 | return &tcpServer{ |
| 20 | addr: addr, |
| 21 | ctx: ctx, |
| 22 | cancel: cancel, |
| 23 | } |
| 24 | } |
| 25 | |
| 26 | type tcpServer struct { |
| 27 | addr string |
| 28 | listener net.Listener |
| 29 | wg sync.WaitGroup |
| 30 | ctx context.Context |
| 31 | cancel context.CancelFunc |
| 32 | } |
| 33 | |
| 34 | func (t *tcpServer) Run() error { |
| 35 | var err error |
| 36 | t.listener, err = net.Listen("tcp", t.addr) |
| 37 | if err != nil { |
| 38 | return fmt.Errorf("failed to start TCP server: %w", err) |
| 39 | } |
| 40 | return t.handleConnections() |
| 41 | } |
| 42 | |
| 43 | func (t *tcpServer) Close() (err error) { |
| 44 | t.cancel() |
| 45 | if t.listener != nil { |
| 46 | if err := t.listener.Close(); err != nil { |
| 47 | return fmt.Errorf("failed to close TCP server: %w", err) |
| 48 | } |
| 49 | } |
| 50 | t.wg.Wait() |
| 51 | return nil |
| 52 | } |
| 53 | |
| 54 | func (t *tcpServer) handleConnections() (err error) { |
| 55 | for { |
| 56 | select { |
| 57 | case <-t.ctx.Done(): |
| 58 | return nil |
| 59 | default: |
| 60 | conn, err := t.listener.Accept() |
| 61 | if err != nil { |
| 62 | if errors.Is(err, net.ErrClosed) { |
| 63 | return nil |
| 64 | } |
| 65 | return fmt.Errorf("could not accept connection: %v", err) |
| 66 | } |
| 67 | t.wg.Go(func() { |
| 68 | t.handleConnection(conn) |
| 69 | }) |
| 70 | } |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | func (t *tcpServer) handleConnection(conn net.Conn) { |
| 75 | defer func() { _ = conn.Close() }() |
| 76 | |
| 77 | if err := conn.SetDeadline(time.Now().Add(time.Second)); err != nil { |
| 78 | return |
| 79 | } |
| 80 | |
| 81 | rw := bufio.NewReadWriter(bufio.NewReader(conn), bufio.NewWriter(conn)) |
| 82 | |
| 83 | if _, err := rw.ReadString('\n'); err != nil { |
| 84 | writeResponse(rw, fmt.Sprintf("failed to read input: %v\n", err)) |
| 85 | } else { |
| 86 | writeResponse(rw, "pong\n") |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | func newUDPServer(addr string) *udpServer { |
| 91 | ctx, cancel := context.WithCancel(context.Background()) |
| 92 | _, addr = parseAddress(addr) |
| 93 | return &udpServer{ |
| 94 | addr: addr, |
| 95 | ctx: ctx, |
| 96 | cancel: cancel, |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | type udpServer struct { |
| 101 | addr string |
| 102 | conn *net.UDPConn |
| 103 | ctx context.Context |
| 104 | cancel context.CancelFunc |
| 105 | } |
| 106 | |
| 107 | func (u *udpServer) Run() error { |
| 108 | addr, err := net.ResolveUDPAddr("udp", u.addr) |
| 109 | if err != nil { |
| 110 | return fmt.Errorf("failed to resolve UDP address: %w", err) |
| 111 | } |
| 112 | |
| 113 | u.conn, err = net.ListenUDP("udp", addr) |
| 114 | if err != nil { |
| 115 | return fmt.Errorf("failed to start UDP server: %w", err) |
| 116 | } |
| 117 | |
| 118 | return u.handleConnections() |
| 119 | } |
| 120 | |
| 121 | func (u *udpServer) Close() (err error) { |
| 122 | u.cancel() |
| 123 | if u.conn != nil { |
| 124 | if err := u.conn.Close(); err != nil { |
| 125 | return fmt.Errorf("failed to close UDP server: %w", err) |
| 126 | } |
| 127 | } |
| 128 | return nil |
| 129 | } |
| 130 | |
| 131 | func (u *udpServer) handleConnections() error { |
| 132 | buffer := make([]byte, 8192) |
| 133 | for { |
| 134 | select { |
| 135 | case <-u.ctx.Done(): |
| 136 | return nil |
| 137 | default: |
| 138 | if err := u.conn.SetReadDeadline(time.Now().Add(time.Second)); err != nil { |
| 139 | continue |
| 140 | } |
| 141 | |
| 142 | _, addr, err := u.conn.ReadFromUDP(buffer[0:]) |
| 143 | if err != nil { |
| 144 | if !errors.Is(err, os.ErrDeadlineExceeded) { |
| 145 | return fmt.Errorf("failed to read UDP packet: %w", err) |
| 146 | } |
| 147 | continue |
| 148 | } |
| 149 | |
| 150 | if _, err := u.conn.WriteToUDP([]byte("pong\n"), addr); err != nil { |
| 151 | return fmt.Errorf("failed to write UDP response: %w", err) |
| 152 | } |
| 153 | } |
| 154 | } |
| 155 | } |
| 156 | |
| 157 | func newUnixServer(addr string) *unixServer { |
| 158 | ctx, cancel := context.WithCancel(context.Background()) |
| 159 | _, addr = parseAddress(addr) |
| 160 | return &unixServer{ |
| 161 | addr: addr, |
| 162 | ctx: ctx, |
| 163 | cancel: cancel, |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | type unixServer struct { |
| 168 | addr string |
| 169 | listener *net.UnixListener |
| 170 | wg sync.WaitGroup |
| 171 | ctx context.Context |
| 172 | cancel context.CancelFunc |
| 173 | } |
| 174 | |
| 175 | func (u *unixServer) Run() error { |
| 176 | if err := os.Remove(u.addr); err != nil && !os.IsNotExist(err) { |
| 177 | return fmt.Errorf("failed to clean up existing socket: %w", err) |
| 178 | } |
| 179 | |
| 180 | addr, err := net.ResolveUnixAddr("unix", u.addr) |
| 181 | if err != nil { |
| 182 | return fmt.Errorf("failed to resolve Unix address: %w", err) |
| 183 | } |
| 184 | |
| 185 | u.listener, err = net.ListenUnix("unix", addr) |
| 186 | if err != nil { |
| 187 | return fmt.Errorf("failed to start Unix server: %w", err) |
| 188 | } |
| 189 | |
| 190 | return u.handleConnections() |
| 191 | } |
| 192 | |
| 193 | func (u *unixServer) Close() error { |
| 194 | u.cancel() |
| 195 | |
| 196 | if u.listener != nil { |
| 197 | if err := u.listener.Close(); err != nil { |
| 198 | return fmt.Errorf("failed to close Unix server: %w", err) |
| 199 | } |
| 200 | } |
| 201 | |
| 202 | u.wg.Wait() |
| 203 | _ = os.Remove(u.addr) |
| 204 | |
| 205 | return nil |
| 206 | } |
| 207 | |
| 208 | func (u *unixServer) handleConnections() error { |
| 209 | for { |
| 210 | select { |
| 211 | case <-u.ctx.Done(): |
| 212 | return nil |
| 213 | default: |
| 214 | if err := u.listener.SetDeadline(time.Now().Add(time.Second)); err != nil { |
| 215 | continue |
| 216 | } |
| 217 | |
| 218 | conn, err := u.listener.AcceptUnix() |
| 219 | if err != nil { |
| 220 | if !errors.Is(err, os.ErrDeadlineExceeded) { |
| 221 | return err |
| 222 | } |
| 223 | continue |
| 224 | } |
| 225 | |
| 226 | u.wg.Go(func() { |
| 227 | u.handleConnection(conn) |
| 228 | }) |
| 229 | } |
| 230 | } |
| 231 | } |
| 232 | |
| 233 | func (u *unixServer) handleConnection(conn net.Conn) { |
| 234 | defer func() { _ = conn.Close() }() |
| 235 | |
| 236 | if err := conn.SetDeadline(time.Now().Add(time.Second)); err != nil { |
| 237 | return |
| 238 | } |
| 239 | |
| 240 | rw := bufio.NewReadWriter(bufio.NewReader(conn), bufio.NewWriter(conn)) |
| 241 | |
| 242 | if _, err := rw.ReadString('\n'); err != nil { |
| 243 | writeResponse(rw, fmt.Sprintf("failed to read input: %v\n", err)) |
| 244 | } else { |
| 245 | writeResponse(rw, "pong\n") |
| 246 | } |
| 247 | |
| 248 | } |
| 249 | |
| 250 | func writeResponse(rw *bufio.ReadWriter, response string) { |
| 251 | _, _ = rw.WriteString(response) |
| 252 | _ = rw.Flush() |
| 253 | } |