Fossil

** backoffice_run_if_needed() will consult this variable to see if it
** should be a no-op.
*/
static char *backofficeDb = 0;

/* End of state variables
****************************************************************************/

/*
** This function emits a diagnostic message related to the processing in
** this module.
*/
#if defined(_WIN32)
# define BKOFCE_ALWAYS_TRACE   (1)
#else
# define BKOFCE_ALWAYS_TRACE   (0)
#endif
static void backofficeTrace(const char *zFormat, ...){
  char *zMsg = 0;
  if( BKOFCE_ALWAYS_TRACE || g.fAnyTrace ){
    va_list ap;
    va_start(ap, zFormat);
    zMsg = sqlite3_vmprintf(zFormat, ap);
    va_end(ap);
#if defined(_WIN32)
    sqlite3_win32_write_debug(zMsg, -1);
#endif
  }
  if( g.fAnyTrace ) fprintf(stderr, "%s", zMsg);
  if( zMsg ) sqlite3_free(zMsg);
}

/*
** Do not allow backoffice processes to sleep waiting on a timeslot.
** They must either do their work immediately or exit.
**
** In a perfect world, this interface would not exist, as there would
** never be a problem with waiting backoffice threads.  But in some cases

      /* This process can start doing backoffice work immediately */
      x.idCurrent = idSelf;
      x.tmCurrent = tmNow + BKOFCE_LEASE_TIME;
      x.idNext = 0;
      x.tmNext = 0;
      backofficeWriteLease(&x);
      db_end_transaction(0);

      backofficeTrace("/***** Begin Backoffice Processing %d *****/\n",
                      GETPID());

      backoffice_work();
      break;
    }
    if( backofficeNoDelay || db_get_boolean("backoffice-nodelay",0) ){
      /* If the no-delay flag is set, exit immediately rather than queuing
      ** up.  Assume that some future request will come along and handle any
      ** necessary backoffice work. */
      db_end_transaction(0);
      break;
    }
    /* This process needs to queue up and wait for the current lease
    ** to expire before continuing. */
    x.idNext = idSelf;
    x.tmNext = (tmNow>x.tmCurrent ? tmNow : x.tmCurrent) + BKOFCE_LEASE_TIME;
    backofficeWriteLease(&x);
    db_end_transaction(0);

    backofficeTrace("/***** Backoffice On-deck %d *****/\n",  GETPID());

    if( x.tmCurrent >= tmNow ){
      if( backofficeSleep(1000*(x.tmCurrent - tmNow + 1)) ){
        /* The sleep was interrupted by a signal from another thread. */

        backofficeTrace("/***** Backoffice Interrupt %d *****/\n", GETPID());

        db_end_transaction(0);
        break;
      }
    }else{
      if( lastWarning+warningDelay < tmNow ){
        fossil_warning(
           "backoffice process %lld still running after %d seconds",
           x.idCurrent, (int)(BKOFCE_LEASE_TIME + tmNow - x.tmCurrent));
        lastWarning = tmNow;
        warningDelay *= 2;
      }
      if( backofficeSleep(1000) ){
        /* The sleep was interrupted by a signal from another thread. */

        backofficeTrace("/***** Backoffice Interrupt %d *****/\n", GETPID());

        db_end_transaction(0);
        break;
      }
    }
  }
#if defined(_WIN32)
  backofficeWin32ThreadCleanup(1);

    argv[1] = "backoffice";
    argv[2] = "-R";
    argv[3] = backofficeDb;
    ax[4] = 0;
    for(i=0; i<=3; i++) ax[i] = fossil_utf8_to_unicode(argv[i]);
    x = _wspawnv(_P_NOWAIT, ax[0], (const wchar_t * const *)ax);
    for(i=0; i<=3; i++) fossil_unicode_free(ax[i]);
    backofficeTrace(

      "/***** Subprocess %d creates backoffice child %d *****/\n",
      GETPID(), (int)x);

    if( x>=0 ) return;
  }
#else /* unix */
  {
    pid_t pid = fork();
    if( pid>0 ){
      /* This is the parent in a successful fork().  Return immediately. */
      backofficeTrace(

        "/***** Subprocess %d creates backoffice child %d *****/\n",
        GETPID(), (int)pid);

      return;
    }
    if( pid==0 ){
      /* This is the child of a successful fork().  Run backoffice. */
      setsid();
      db_open_repository(backofficeDb);
      backofficeDb = "x";
      backoffice_thread();
      db_close(1);

      backofficeTrace("/***** Backoffice Child %d exits *****/\n", GETPID());

      exit(0);
    }
  }
#endif
  /* Fork() failed or is unavailable.  Run backoffice in this process, but
  ** do so with the no-delay setting.
  */
  backofficeNoDelay = 1;
  db_open_repository(backofficeDb);
  backofficeDb = "x";
  backoffice_thread();
  db_close(1);
}