/* ISC license. */

#include <string.h>
#include <sys/wait.h>

#include <skalibs/posixplz.h>
#include <skalibs/uint64.h>
#include <skalibs/types.h>
#include <skalibs/strerr.h>
#include <skalibs/gol.h>
#include <skalibs/env.h>
#include <skalibs/cspawn.h>
#include <skalibs/djbunix.h>

#include <s6-rc/config.h>
#include <s6-rc/s6rc-utils.h>

#include "s6-internal.h"

#define USAGE "s6 service start services..."
#define dieusage() strerr_dieusage(100, USAGE)

enum service_start_golb_e
{
  SERVICE_START_GOLB_DRYRUN,
  SERVICE_START_GOLB_WAIT,
  SERVICE_START_GOLB_N
} ;

enum service_start_gola_e
{
  SERVICE_START_GOLA_TIMEOUT,
  SERVICE_START_GOLA_N
} ;

static gol_bool const service_start_golb[3] =
{
  { .so = 'n', .lo = "dryrun", .set = 1, .mask = 1 << SERVICE_START_GOLB_DRYRUN },
  { .so = 'W', .lo = "nowait", .set = 0, .mask = 1 << SERVICE_START_GOLB_WAIT },
  { .so = 'w', .lo = "wait", .set = 1, .mask = 1 << SERVICE_START_GOLB_WAIT }
} ;

static gol_arg const service_start_gola[SERVICE_START_GOLA_N] =
{
  { .so = 't', .lo = "timeout", .i = SERVICE_START_GOLA_TIMEOUT }
} ;

int service_start (char const *const *argv)
{
  char const *gola[SERVICE_START_GOLA_N] = { 0 } ;
  uint64_t golb = 0 ;
  unsigned int t = 0 ;
  size_t argc = env_len(argv) ;
  pid_t pid ;
  int wstat ;
  uint32_t nlong, nshort, n ;
  int livelock, compiledlock ;
  size_t livelen = strlen(g->dirs.live) ;
  PROG = "s6 service start" ;

  argv += gol_argv(argv, service_start_golb, 3, service_start_gola, SERVICE_START_GOLA_N, &golb, gola) ;
  if (!*argv) dieusage() ;

  if (gola[SERVICE_START_GOLA_TIMEOUT])
  {
    if (!uint0_scan(gola[SERVICE_START_GOLA_TIMEOUT], &t))
      strerr_dief1x(100, "timeout must be an integer (milliseconds)") ;
  }
  s6f_lock(g->dirs.stmp, 0) ;  /* leaks, it's fine */
  char dbfn[livelen + 10] ;
  memcpy(dbfn, g->dirs.live, livelen) ;
  memcpy(dbfn + livelen, "/compiled", 10) ;
  if (!s6rc_lock(g->dirs.live, 2, &livelock, dbfn, 1, &compiledlock, 1))
    strerr_diefu2sys(111, "take lock in ", g->dirs.live) ;
  if (!s6rc_live_state_size(g->dirs.live, &nlong, &nshort))
    strerr_diefu2sys(111, "read state size in ", g->dirs.live) ;
  n = nlong + nshort ;
  unsigned char oldstate[n] ;
  if (!s6rc_live_state_read(g->dirs.live, oldstate, n))
    strerr_diefu2sys(111, "read state in ", g->dirs.live) ;

  {
    size_t m = 0 ;
    char const *newargv[13 + argc] ;
    char fmtv[UINT_FMT] ;
    char fmtt[UINT_FMT] ;

    newargv[m++] = S6RC_EXTBINPREFIX "s6-rc" ;
    newargv[m++] = "-X" ;  /* we already took the locks */
    newargv[m++] = "-v" ;
    newargv[m++] = fmtv ;
    fmtv[uint_fmt(fmtv, g->verbosity)] = 0 ;
    if (t)
    {
      newargv[m++] = "-t" ;
      newargv[m++] = fmtt ;
      fmtt[uint_fmt(fmtt, t)] = 0 ;
    }
    if (golb & 1 << SERVICE_START_GOLB_DRYRUN)
    {
      newargv[m++] = "-n" ;
      newargv[m++] = "1" ;
    }
    newargv[m++] = "-l" ;
    newargv[m++] = g->dirs.live ;
    newargv[m++] = "--" ;
    newargv[m++] = "start" ;
    while (*argv) newargv[m++] = *argv++ ;
    newargv[m++] = 0 ;
    pid = cspawn(newargv[0], newargv, (char const *const *)environ, CSPAWN_FLAGS_SIGBLOCKNONE, 0, 0) ;
    if (!pid) strerr_diefu2sys(111, "spawn ", newargv[0]) ;
  }
  if (wait_pid(pid, &wstat) <= 0) strerr_diefu1sys(111, "wait for s6-rc") ;
  if ((WIFEXITED(wstat) && !WEXITSTATUS(wstat)) || !g->verbosity)
    return wait_estatus(wstat) ;

  unsigned char newstate[n] ;
  if (!s6rc_live_state_read(g->dirs.live, newstate, n))
    strerr_diefu2sys(111, "read state in ", g->dirs.live) ;
  s6f_report_state_change(n, oldstate, newstate, dbfn) ;
  return wait_estatus(wstat) ;
}