summaryrefslogtreecommitdiff
path: root/src/supervision/s6-svc.c
blob: acf8e06c7547aa65db4e008f8ebcc48cb50ea582 (plain)
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
/* ISC license. */

#include <skalibs/nonposix.h>

#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <signal.h>

#include <skalibs/types.h>
#include <skalibs/sgetopt.h>
#include <skalibs/strerr.h>
#include <skalibs/nsig.h>
#include <skalibs/sig.h>
#include <skalibs/djbunix.h>
#include <skalibs/exec.h>

#include <s6/config.h>
#include <s6/supervise.h>

#define USAGE "s6-svc [ -wu | -wU | -wd | -wD | -wr | -wR ] [ -T timeout ] [ -s signal | -abqhkti12pcy ] [ -roduDUxOQ ] servicedir"
#define dieusage() strerr_dieusage(100, USAGE)

#define DATASIZE 63

int main (int argc, char const *const *argv)
{
  static char const cmdsig[NSIG] =
  {
    0,
    [SIGALRM] = 'a',
    [SIGABRT] = 'b',
    [SIGQUIT] = 'q',
    [SIGHUP] = 'h',
    [SIGKILL] = 'k',
    [SIGTERM] = 't',
    [SIGINT] = 'i',
    [SIGUSR1] = '1',
    [SIGUSR2] = '2',
    [SIGSTOP] = 'p',
    [SIGCONT] = 'c',
    [SIGWINCH] = 'y'
  } ;
  size_t len ;
  unsigned int datalen = 1 ;
  unsigned int timeout = 0 ;
  char data[DATASIZE+1] = "-" ;
  char updown[3] = "-\0" ;
  PROG = "s6-svc" ;
  {
    subgetopt l = SUBGETOPT_ZERO ;
    for (;;)
    {
      int opt = subgetopt_r(argc, argv, "s:abqhkti12pcyroduDUxOQT:w:", &l) ;
      if (opt == -1) break ;
      switch (opt)
      {
        case 's' :
        {
          int sig ;
          if (!sig0_scan(l.arg, &sig)) strerr_dief2x(100, "invalid signal: ", l.arg) ;
          if (!cmdsig[sig]) strerr_dief2x(100, l.arg, " is not in the list of user-available signals") ;
          opt = cmdsig[sig] ;
        }
        case 'a' :
        case 'b' :
        case 'q' :
        case 'h' :
        case 'k' :
        case 't' :
        case 'i' :
        case '1' :
        case '2' :
        case 'p' :
        case 'c' :
        case 'y' :
        case 'r' :
        case 'o' :
        case 'd' :
        case 'u' :
        case 'D' :
        case 'U' :
        case 'x' :
        case 'O' :
        case 'Q' :
        {
          if (datalen >= DATASIZE) strerr_dief1x(100, "too many commands") ;
          data[datalen++] = opt ;
          break ;
        }
        case 'T' : if (!uint0_scan(l.arg, &timeout)) dieusage() ; break ;
        case 'w' :
        {
          if (!memchr("dDuUrR", l.arg[0], 6)) dieusage() ;
          updown[1] = l.arg[0] ;
          break ;
        }
        default : dieusage() ;
      }
    }
    argc -= l.ind ; argv += l.ind ;
  }
  if (!argc) dieusage() ;
  if (argc > 1) strerr_warnw1x("ignoring extra arguments") ;
  len = strlen(argv[0]) ;
  if (!len) strerr_dief1x(100, "invalid service path") ;

  if (updown[1] == 'U' || updown[1] == 'R')
  {
    char fn[len + 17] ;
    memcpy(fn, argv[0], len) ;
    memcpy(fn + len, "/notification-fd", 17) ;
    if (access(fn, F_OK) < 0)
    {
      if (errno != ENOENT) strerr_diefu2sys(111, "access ", fn) ;
      updown[1] = updown[1] == 'U' ? 'u' : 'r' ;
      strerr_warnw2x(fn, " not present - ignoring request for readiness notification") ;
    }
  }

  if (updown[1])
  {
    char const *newargv[11] ;
    unsigned int m = 0 ;
    char fmt[UINT_FMT] ;
    newargv[m++] = datalen > 1 ? S6_BINPREFIX "s6-svlisten1" : S6_BINPREFIX "s6-svwait" ;
    newargv[m++] = updown ;
    if (timeout)
    {
      fmt[uint_fmt(fmt, timeout)] = 0 ;
      newargv[m++] = "-t" ;
      newargv[m++] = fmt ;
    }
    newargv[m++] = "--" ;
    newargv[m++] = argv[0] ;
    if (datalen > 1)
    {
      newargv[m++] = S6_BINPREFIX "s6-svc" ;
      newargv[m++] = data ;
      newargv[m++] = "--" ;
      newargv[m++] = argv[0] ;
    }
    newargv[m++] = 0 ;
    xexec(newargv) ;
  }
  else switch (s6_svc_writectl(argv[0], S6_SUPERVISE_CTLDIR, data + 1, datalen - 1))
  {
    case -1 : strerr_diefu2sys(111, "control ", argv[0]) ;
    case -2 : strerr_dief3sys(100, "something is wrong with the ", argv[0], "/" S6_SUPERVISE_CTLDIR " directory") ;
    case 0 : strerr_diefu3x(100, "control ", argv[0], ": supervisor not listening") ;
  }
  return 0 ;
}