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1 // Helper copied to the remote host to run commands and deploy configuration
2
3 // Copyright (C) 2021-2023  Simon Ruderich
4 //
5 // This program is free software: you can redistribute it and/or modify
6 // it under the terms of the GNU General Public License as published by
7 // the Free Software Foundation, either version 3 of the License, or
8 // (at your option) any later version.
9 //
10 // This program is distributed in the hope that it will be useful,
11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 // GNU General Public License for more details.
14 //
15 // You should have received a copy of the GNU General Public License
16 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
17
18 package remote
19
20 import (
21         "fmt"
22         "log"
23         "os"
24
25         "golang.org/x/term"
26
27         "ruderich.org/simon/safcm"
28         "ruderich.org/simon/safcm/remote/ainsl"
29         "ruderich.org/simon/safcm/remote/info"
30         "ruderich.org/simon/safcm/remote/run"
31         "ruderich.org/simon/safcm/remote/sync"
32 )
33
34 func usage() {
35         log.Fatalf("usage: %[1]s sync\n"+
36                 "usage: %[1]s ainsl [options] <path> <line>",
37                 os.Args[0])
38 }
39
40 func Main() {
41         // Timestamps are added by `safcm`
42         log.SetFlags(0)
43
44         if len(os.Args) < 2 {
45                 usage()
46         }
47
48         var err error
49         switch os.Args[1] {
50         case "sync":
51                 if len(os.Args) != 2 {
52                         usage()
53                 }
54                 err = mainLoop()
55         case "ainsl":
56                 err = ainsl.Main(os.Args)
57         default:
58                 usage()
59         }
60
61         if err != nil {
62                 log.Fatalf("%s: %v", os.Args[0], err)
63         }
64 }
65
66 func mainLoop() error {
67         if term.IsTerminal(int(os.Stdin.Fd())) ||
68                 term.IsTerminal(int(os.Stdout.Fd())) {
69                 return fmt.Errorf("sync should only be called from `safcm` " +
70                         "(redirect stdin/stdout to circumvent this check)")
71         }
72
73         conn := safcm.NewGobConn(os.Stdin, os.Stdout)
74
75         var logLevel safcm.LogLevel
76         logFunc := func(level safcm.LogLevel, msg string) {
77                 if logLevel >= level {
78                         // Handling errors here is complex and quite verbose.
79                         // If it happens the connection is gone anyway so skip
80                         // the error handling.
81                         conn.Send(safcm.MsgLog{ //nolint:errcheck
82                                 Level: level,
83                                 Text:  msg,
84                         })
85                 }
86         }
87
88         var quitResp safcm.MsgQuitResp
89         for {
90                 x, err := conn.Recv()
91                 if err != nil {
92                         return err
93                 }
94
95                 var resp safcm.Msg
96                 switch x := x.(type) {
97                 case safcm.MsgInfoReq:
98                         logLevel = x.LogLevel // set log level globally
99                         resp = info.Handle(x, run.ExecRunner{}, logFunc)
100                 case safcm.MsgSyncReq:
101                         resp = sync.Handle(x, run.ExecRunner{}, logFunc)
102                 case safcm.MsgQuitReq:
103                         resp = quitResp
104                 default:
105                         return fmt.Errorf("unsupported message %#v", x)
106                 }
107
108                 err = conn.Send(resp)
109                 if err != nil {
110                         return err
111                 }
112                 if resp == quitResp {
113                         break
114                 }
115         }
116         return nil
117 }