コード例 #1
0
ファイル: vor.c プロジェクト: alecbrick/urbit
/* functions
*/
  u3_noun
  u3qc_vor(u3_atom a,
                   u3_atom b)
  {
    c3_w c_w = u3r_mug(u3r_mug(a));
    c3_w d_w = u3r_mug(u3r_mug(b));

    if ( c_w == d_w ) {
      return u3qc_dor(a, b);
    }
    else return (c_w < d_w) ? c3y : c3n;
  }
コード例 #2
0
ファイル: unix.c プロジェクト: juped/your-urbit
/* _unix_write_file_soft(): write to a file, not overwriting if it's changed
*/
static void
_unix_write_file_soft(u3_ufil* fil_u, u3_noun mim)
{
    struct stat buf_u;
    c3_i  fid_i = open(fil_u->pax_c, O_RDONLY, 0644);
    c3_ws len_ws, red_ws;
    c3_w  old_w;
    c3_y* old_y;

    if ( fid_i < 0 || fstat(fid_i, &buf_u) < 0 ) {
        if ( ENOENT == errno ) {
            goto _unix_write_file_soft_go;
        }
        else {
            uL(fprintf(uH, "error opening file (soft) %s: %s\r\n",
                       fil_u->pax_c, strerror(errno)));
            u3z(mim);
            return;
        }
    }

    len_ws = buf_u.st_size;
    old_y = c3_malloc(len_ws);

    red_ws = read(fid_i, old_y, len_ws);

    if ( close(fid_i) < 0 ) {
        uL(fprintf(uH, "error closing file (soft) %s: %s\r\n",
                   fil_u->pax_c, strerror(errno)));
    }

    if ( len_ws != red_ws ) {
        if ( red_ws < 0 ) {
            uL(fprintf(uH, "error reading file (soft) %s: %s\r\n",
                       fil_u->pax_c, strerror(errno)));
        }
        else {
            uL(fprintf(uH, "wrong # of bytes read in file %s: %d %d\r\n",
                       fil_u->pax_c, len_ws, red_ws));
        }
        free(old_y);
        u3z(mim);
        return;
    }

    old_w = u3r_mug_bytes(old_y, len_ws);

    if ( old_w != fil_u->gum_w ) {
        fil_u->gum_w = u3r_mug(u3t(u3t(mim))); // XXX this might fail with
        free(old_y);                           //     trailing zeros
        u3z(mim);
        return;
    }

    free(old_y);

_unix_write_file_soft_go:
    fil_u->gum_w = _unix_write_file_hard(fil_u->pax_c, mim);
}
コード例 #3
0
ファイル: sist.c プロジェクト: wrmsr/urbit
/* _sist_rest(): restore from record, or exit.
*/
static void
_sist_rest()
{
  struct stat buf_b;
  c3_i        fid_i;
  c3_c        ful_c[2048];
  c3_d        old_d = u3A->ent_d;
  c3_d        las_d = 0;
  u3_noun     roe = u3_nul;
  u3_noun     sev_l, key_l, sal_l;
  u3_noun     ohh = c3n;

  if ( 0 != u3A->ent_d ) {
    u3_noun ent;
    c3_c*   ent_c;

    ent = u3i_chubs(1, &u3A->ent_d);
    ent = u3dc("scot", c3__ud, ent);
    ent_c = u3r_string(ent);
    uL(fprintf(uH, "rest: checkpoint to event %s\n", ent_c));
    free(ent_c);
    u3z(ent);
  }

  //  Open the fscking file.  Does it even exist?
  {
    c3_i pig_i = O_RDWR;
#ifdef O_DSYNC
    pig_i |= O_DSYNC;
#endif
    snprintf(ful_c, 2048, "%s/.urb/egz.hope", u3_Host.dir_c);
    if ( ((fid_i = open(ful_c, pig_i)) < 0) || (fstat(fid_i, &buf_b) < 0) ) {
      uL(fprintf(uH, "rest: can't open record (%s)\n", ful_c));
      u3_lo_bail();

      return;
    }
#ifdef F_NOCACHE
    if ( -1 == fcntl(fid_i, F_NOCACHE, 1) ) {
      uL(fprintf(uH, "rest: can't uncache %s: %s\n", ful_c, strerror(errno)));
      u3_lo_bail();

      return;
    }
#endif
    u3Z->lug_u.fid_i = fid_i;
    u3Z->lug_u.len_d = ((buf_b.st_size + 3ULL) >> 2ULL);
  }

  //  Check the fscking header.  It's probably corrupt.
  {
    u3_uled led_u;

    if ( sizeof(led_u) != read(fid_i, &led_u, sizeof(led_u)) ) {
      uL(fprintf(uH, "record (%s) is corrupt (a)\n", ful_c));
      u3_lo_bail();
    }

    if ( u3r_mug('f') == led_u.mag_l ) {
      _sist_rest_nuu(&u3Z->lug_u, led_u, ful_c);
      fid_i = u3Z->lug_u.fid_i;
    }
    else if (u3r_mug('g') != led_u.mag_l ) {
      uL(fprintf(uH, "record (%s) is obsolete (or corrupt)\n", ful_c));
      u3_lo_bail();
    }

    if ( led_u.kno_w != 163 ) {
      //  XX perhaps we should actually do something here
      //
      uL(fprintf(uH, "rest: (not) translating events (old %d, now %d)\n",
                     led_u.kno_w,
                     163));
    }
    sev_l = led_u.sev_l;
    sal_l = led_u.sal_l;
    key_l = led_u.key_l;

    {
      u3_noun old = u3dc("scot", c3__uv, sev_l);
      u3_noun nuu = u3dc("scot", c3__uv, u3A->sev_l);
      c3_c* old_c = u3r_string(old);
      c3_c* nuu_c = u3r_string(nuu);

      uL(fprintf(uH, "rest: old %s, new %s\n", old_c, nuu_c));
      free(old_c); free(nuu_c);

      u3z(old); u3z(nuu);
    }
    c3_assert(sev_l != u3A->sev_l);   //  1 in 2 billion, just retry
  }

  //  Oh, and let's hope you didn't forget the fscking passcode.
  {
    if ( 0 != key_l ) {
      u3_noun pas = _sist_staf(key_l);
      u3_noun key;

      while ( 1 ) {
        pas = pas ? pas : _sist_cask(u3_Host.dir_c, c3n);

        key = _sist_fatt(sal_l, pas);

        if ( u3r_mug(key) != key_l ) {
          uL(fprintf(uH, "incorrect passcode\n"));
          u3z(key);
          pas = 0;
        }
        else {
          u3z(u3A->key);
          u3A->key = key;
          break;
        }
      }
    }
  }

  //  Read in the fscking events.  These are probably corrupt as well.
  {
    c3_d    ent_d;
    c3_d    end_d;
    u3_noun rup = c3n;

    end_d = u3Z->lug_u.len_d;
    ent_d = 0;

    if ( -1 == lseek64(fid_i, 4ULL * end_d, SEEK_SET) ) {
      fprintf(stderr, "end_d %" PRIu64 "\n", end_d);
      perror("lseek");
      uL(fprintf(uH, "record (%s) is corrupt (c)\n", ful_c));
      u3_lo_bail();
    }

    while ( end_d != c3_wiseof(u3_uled) ) {
      c3_d    tar_d = (end_d - (c3_d)c3_wiseof(u3_ular));
      u3_ular lar_u;
      c3_w*   img_w;
      u3_noun ron;

      // uL(fprintf(uH, "rest: reading event at %" PRIx64 "\n", end_d));

      if ( -1 == lseek64(fid_i, 4ULL * tar_d, SEEK_SET) ) {
        uL(fprintf(uH, "record (%s) is corrupt (d)\n", ful_c));
        u3_lo_bail();
      }
      if ( sizeof(u3_ular) != read(fid_i, &lar_u, sizeof(u3_ular)) ) {
        uL(fprintf(uH, "record (%s) is corrupt (e)\n", ful_c));
        u3_lo_bail();
      }

      if ( lar_u.syn_w != u3r_mug((c3_w)tar_d) ) {
        if ( c3n == rup ) {
          uL(fprintf(uH, "corruption detected; attempting to fix\n"));
          rup = c3y;
        }
        uL(fprintf(uH, "lar:%x mug:%x\n", lar_u.syn_w, u3r_mug((c3_w)tar_d)));
        end_d--; u3Z->lug_u.len_d--;
        continue;
      }
      else if ( c3y == rup ) {
        uL(fprintf(uH, "matched at %x\n", lar_u.syn_w));
        rup = c3n;
      }

      if ( lar_u.ent_d == 0 ) {
        ohh = c3y;
      }

#if 0
      uL(fprintf(uH, "log: read: at %d, %d: lar ent %" PRIu64 ", len %d, mug %x\n",
                      (tar_w - lar_u.len_w),
                      tar_w,
                      lar_u.ent_d,
                      lar_u.len_w,
                      lar_u.mug_w));
#endif
      if ( end_d == u3Z->lug_u.len_d ) {
        ent_d = las_d = lar_u.ent_d;
      }
      else {
        if ( lar_u.ent_d != (ent_d - 1ULL) ) {
          uL(fprintf(uH, "record (%s) is corrupt (g)\n", ful_c));
          uL(fprintf(uH, "lar_u.ent_d %" PRIx64 ", ent_d %" PRIx64 "\n", lar_u.ent_d, ent_d));
          u3_lo_bail();
        }
        ent_d -= 1ULL;
      }
      end_d = (tar_d - (c3_d)lar_u.len_w);

      if ( ent_d < old_d ) {
        //  XX this could be a break if we didn't want to see the sequence
        //  number of the first event.
        continue;
      }

      img_w = c3_malloc(4 * lar_u.len_w);

      if ( -1 == lseek64(fid_i, 4ULL * end_d, SEEK_SET) ) {
        uL(fprintf(uH, "record (%s) is corrupt (h)\n", ful_c));
        u3_lo_bail();
      }
      if ( (4 * lar_u.len_w) != read(fid_i, img_w, (4 * lar_u.len_w)) ) {
        uL(fprintf(uH, "record (%s) is corrupt (i)\n", ful_c));
        u3_lo_bail();
      }

      ron = u3i_words(lar_u.len_w, img_w);
      free(img_w);

      if ( lar_u.mug_w !=
            u3r_mug_both(u3r_mug(ron),
                           u3r_mug_both(u3r_mug(lar_u.tem_w),
                                          u3r_mug(lar_u.typ_w))) )
      {
        uL(fprintf(uH, "record (%s) is corrupt (j)\n", ful_c));
        u3_lo_bail();
      }

      if ( c3__ov != lar_u.typ_w ) {
        u3z(ron);
        continue;
      }

      if ( u3A->key ) {
        u3_noun dep;

        dep = u3dc("de:crua", u3k(u3A->key), ron);
        if ( c3n == u3du(dep) ) {
          uL(fprintf(uH, "record (%s) is corrupt (k)\n", ful_c));
          u3_lo_bail();
        }
        else {
          ron = u3k(u3t(dep));
          u3z(dep);
        }
      }
      roe = u3nc(u3ke_cue(ron), roe);
    }
    u3A->ent_d = c3_max(las_d + 1ULL, old_d);
  }

  if ( u3_nul == roe ) {
    //  Nothing in the log that was not also in the checkpoint.
    //
    c3_assert(u3A->ent_d == old_d);
    if ( las_d + 1 != old_d ) {
      uL(fprintf(uH, "checkpoint and log disagree! las:%" PRIu64 " old:%" PRIu64 "\n",
                     las_d + 1, old_d));
      uL(fprintf(uH, "Some events appear to be missing from the log.\n"
                     "Please contact the authorities, "
                     "and do not delete your pier!\n"));
      u3_lo_bail();
    }
  }
  else {
    u3_noun rou = roe;
    c3_w    xno_w;

    //  Execute the fscking things.  This is pretty much certain to crash.
    //
    uL(fprintf(uH, "rest: replaying through event %" PRIu64 "\n", las_d));
    fprintf(uH, "---------------- playback starting----------------\n");

    xno_w = 0;
    while ( u3_nul != roe ) {
      u3_noun i_roe = u3h(roe);
      u3_noun t_roe = u3t(roe);
      u3_noun now = u3h(i_roe);
      u3_noun ovo = u3t(i_roe);

      u3v_time(u3k(now));
      if ( (c3y == u3_Host.ops_u.vno) &&
           ( (c3__veer == u3h(u3t(ovo)) ||
             (c3__vega == u3h(u3t(ovo)))) ) )
      {
        fprintf(stderr, "replay: skipped veer\n");
      }
      else if ( c3y == u3_Host.ops_u.fog &&
                u3_nul == t_roe ) {
        fprintf(stderr, "replay: -Xwtf, skipped last event\n");
      }
      else {
        _sist_sing(u3k(ovo));
        fputc('.', stderr);
      }

      // fprintf(stderr, "playback: sing: %d\n", xno_w));

      roe = t_roe;
      xno_w++;

      if ( 0 == (xno_w % 1000) ) {
        uL(fprintf(uH, "{%d}\n", xno_w));
        // u3_lo_grab("rest", rou, u3_none);
      }
    }
    u3z(rou);
  }
  uL(fprintf(stderr, "\n---------------- playback complete----------------\n"));

#if 0
  //  If you see this error, your record is totally fscking broken!
  //  Which probably serves you right.  Please consult a consultant.
  {
    if ( u3_nul == u3A->own ) {
      uL(fprintf(uH, "record did not install a master!\n"));
      u3_lo_bail();
    }
    u3A->our = u3k(u3h(u3A->own));
    u3A->pod = u3dc("scot", 'p', u3k(u3A->our)));
  }

  //  Now, who the fsck are you?  No, really.
  {
    u3_noun who;
    c3_c*   fil_c;
    c3_c*   who_c;

    if ( (fil_c = strrchr(u3_Host.dir_c, '/')) ) {
      fil_c++;
    } else fil_c = u3_Host.dir_c;

    who = u3dc("scot", 'p', u3k(u3A->our)));
    who_c = u3r_string(who);
    u3z(who);

    if ( strncmp(fil_c, who_c + 1, strlen(fil_c)) ) {
      uL(fprintf(uH, "record master (%s) does not match filename!\n", who_c));
      u3_lo_bail();
    }
    free(who_c);
  }
#endif

  //  Increment sequence numbers. New logs start at 1.
  if ( c3y == ohh ) {
    uL(fprintf(uH, "rest: bumping ent_d, don't panic.\n"));
    u3_ular lar_u;
    c3_d    end_d;
    c3_d    tar_d;

    u3A->ent_d++;
    end_d = u3Z->lug_u.len_d;
    while ( end_d != c3_wiseof(u3_uled) ) {
      tar_d = end_d - c3_wiseof(u3_ular);
      if ( -1 == lseek64(fid_i, 4ULL * tar_d, SEEK_SET) ) {
        uL(fprintf(uH, "bumping sequence numbers failed (a)\n"));
        u3_lo_bail();
      }
      if ( sizeof(lar_u) != read(fid_i, &lar_u, sizeof(lar_u)) ) {
        uL(fprintf(uH, "bumping sequence numbers failed (b)\n"));
        u3_lo_bail();
      }
      lar_u.ent_d++;
      if ( -1 == lseek64(fid_i, 4ULL * tar_d, SEEK_SET) ) {
        uL(fprintf(uH, "bumping sequence numbers failed (c)\n"));
        u3_lo_bail();
      }
      if ( sizeof(lar_u) != write(fid_i, &lar_u, sizeof(lar_u)) ) {
        uL(fprintf(uH, "bumping sequence numbers failed (d)\n"));
        u3_lo_bail();
      }
      end_d = tar_d - lar_u.len_w;
    }
  }

  //  Rewrite the header.  Will probably corrupt the record.
  {
    u3_uled led_u;

    led_u.mag_l = u3r_mug('g');
    led_u.sal_l = sal_l;
    led_u.sev_l = u3A->sev_l;
    led_u.key_l = u3A->key ? u3r_mug(u3A->key) : 0;
    led_u.kno_w = 163;         //  may need actual translation!
    led_u.tno_l = 1;

    if ( (-1 == lseek64(fid_i, 0, SEEK_SET)) ||
         (sizeof(led_u) != write(fid_i, &led_u, sizeof(led_u))) )
    {
      uL(fprintf(uH, "record (%s) failed to rewrite\n", ful_c));
      u3_lo_bail();
    }
  }

  //  Hey, fscker!  It worked.
  {
    u3_term_ef_boil();
  }
}
コード例 #4
0
ファイル: sist.c プロジェクト: wrmsr/urbit
/* _sist_rest_nuu(): upgrade log from previous format.
*/
static void
_sist_rest_nuu(u3_ulog* lug_u, u3_uled led_u, c3_c* old_c)
{
  c3_c    nuu_c[2048];
  u3_noun roe = u3_nul;
  c3_i    fid_i = lug_u->fid_i;
  c3_i    fud_i;
  c3_i    ret_i;
  c3_d    end_d = lug_u->len_d;

  uL(fprintf(uH, "rest: converting log from prior format\n"));

  c3_assert(led_u.mag_l == u3r_mug('f'));

  if ( -1 == lseek64(fid_i, 4ULL * end_d, SEEK_SET) ) {
    uL(fprintf(uH, "rest_nuu failed (a)\n"));
    perror("lseek64");
    u3_lo_bail();
  }

  while ( end_d != c3_wiseof(u3_uled) ) {
    c3_d    tar_d;
    u3_olar lar_u;
    c3_w*   img_w;
    u3_noun ron;

    tar_d = (end_d - (c3_d)c3_wiseof(u3_olar));

    if ( -1 == lseek64(fid_i, 4ULL * tar_d, SEEK_SET) ) {
      uL(fprintf(uH, "rest_nuu failed (b)\n"));
      perror("lseek64");
      u3_lo_bail();
    }
    if ( sizeof(u3_olar) != read(fid_i, &lar_u, sizeof(u3_olar)) ) {
      uL(fprintf(uH, "rest_nuu failed (c)\n"));
      perror("read");
      u3_lo_bail();
    }

    if ( lar_u.syn_w != u3r_mug((c3_w)tar_d) ) {
      uL(fprintf(uH, "rest_nuu failed (d)\n"));
      u3_lo_bail();
    }

    img_w = c3_malloc(4 * lar_u.len_w);
    end_d = (tar_d - (c3_d)lar_u.len_w);

    if ( -1 == lseek64(fid_i, 4ULL * end_d, SEEK_SET) ) {
      uL(fprintf(uH, "rest_nuu failed (e)\n"));
      perror("lseek64");
      u3_lo_bail();
    }
    if ( (4 * lar_u.len_w) != read(fid_i, img_w, (4 * lar_u.len_w)) ) {
      uL(fprintf(uH, "rest_nuu failed (f)\n"));
      perror("read");
      u3_lo_bail();
    }

    ron = u3i_words(lar_u.len_w, img_w);
    free(img_w);

    if ( lar_u.mug_w != u3r_mug(ron) ) {
      uL(fprintf(uH, "rest_nuu failed (g)\n"));
      u3_lo_bail();
    }

    roe = u3nc(ron, roe);
  }

  if ( 0 != close(fid_i) ) {
    uL(fprintf(uH, "rest: could not close\n"));
    perror("close");
    u3_lo_bail();
  }

  ret_i = snprintf(nuu_c, 2048, "%s/.urb/ham.hope", u3_Host.dir_c);
  c3_assert(ret_i < 2048);

  if ( (fud_i = open(nuu_c, O_CREAT | O_TRUNC | O_RDWR, 0600)) < 0 ) {
    uL(fprintf(uH, "rest: can't open record (%s)\n", nuu_c));
    perror("open");
    u3_lo_bail();
  }

  led_u.mag_l = u3r_mug('g');
  if ( (sizeof(led_u) != write(fud_i, &led_u, sizeof(led_u))) ) {
    uL(fprintf(uH, "rest: can't write header\n"));
    perror("write");
    u3_lo_bail();
  }

  {
    c3_d ent_d = 1;

    c3_assert(end_d == c3_wiseof(u3_uled));
    while ( u3_nul != roe ) {
      u3_noun ovo = u3k(u3h(roe));
      u3_noun nex = u3k(u3t(roe));
      u3_ular lar_u;
      c3_w*   img_w;
      c3_d    tar_d;

      lar_u.len_w = u3r_met(5, ovo);
      tar_d = end_d + lar_u.len_w;
      lar_u.syn_w = u3r_mug(tar_d);
      lar_u.ent_d = ent_d;
      lar_u.tem_w = 0;
      lar_u.typ_w = c3__ov;
      lar_u.mug_w = u3r_mug_both(u3r_mug(ovo),
                                   u3r_mug_both(u3r_mug(0),
                                                  u3r_mug(c3__ov)));

      img_w = c3_malloc(lar_u.len_w << 2);
      u3r_words(0, lar_u.len_w, img_w, ovo);
      u3z(ovo);

      if ( (lar_u.len_w << 2) != write(fud_i, img_w, lar_u.len_w << 2) ) {
        uL(fprintf(uH, "rest_nuu failed (h)\n"));
        perror("write");
        u3_lo_bail();
      }
      if ( sizeof(u3_ular) != write(fud_i, &lar_u, sizeof(u3_ular)) ) {
        uL(fprintf(uH, "rest_nuu failed (i)\n"));
        perror("write");
        u3_lo_bail();
      }

      ent_d++;
      end_d = tar_d + c3_wiseof(u3_ular);
      u3z(roe); roe = nex;
    }
  }
  if ( 0 != rename(nuu_c, old_c) ) {
    uL(fprintf(uH, "rest_nuu failed (k)\n"));
    perror("rename");
    u3_lo_bail();
  }
  if ( -1 == lseek64(fud_i, sizeof(u3_uled), SEEK_SET) ) {
    uL(fprintf(uH, "rest_nuu failed (l)\n"));
    perror("lseek64");
    u3_lo_bail();
  }
  lug_u->fid_i = fud_i;
  lug_u->len_d = end_d;
}
コード例 #5
0
ファイル: sist.c プロジェクト: wrmsr/urbit
/* _sist_zest(): create a new, empty record.
*/
static void
_sist_zest()
{
  struct stat buf_b;
  c3_i        fid_i;
  c3_c        ful_c[8193];
  c3_l        sal_l;

  //  Create the ship directory.
  //
  _sist_home();

  //  Create the record file.
  {
    c3_i pig_i = O_CREAT | O_WRONLY | O_EXCL;
#ifdef O_DSYNC
    pig_i |= O_DSYNC;
#endif
    snprintf(ful_c, 2048, "%s/.urb/egz.hope", u3_Host.dir_c);

    if ( ((fid_i = open(ful_c, pig_i, 0600)) < 0) ||
         (fstat(fid_i, &buf_b) < 0) )
    {
      uL(fprintf(uH, "can't create record (%s)\n", ful_c));
      u3_lo_bail();
    }
#ifdef F_NOCACHE
    if ( -1 == fcntl(fid_i, F_NOCACHE, 1) ) {
      uL(fprintf(uH, "zest: can't uncache %s: %s\n", ful_c, strerror(errno)));
      u3_lo_bail();
    }
#endif
    u3Z->lug_u.fid_i = fid_i;
  }

  //  Generate a 31-bit salt.
  //
  {
    c3_w rad_w[8];

    c3_rand(rad_w);
    sal_l = (0x7fffffff & rad_w[0]);
  }

  //  Create and save a passcode.
  //
  {
    c3_w rad_w[8];
    u3_noun pas;

    c3_rand(rad_w);
    pas = u3i_words(2, rad_w);

    u3A->key = _sist_fatt(sal_l, u3k(pas));
    _sist_fast(pas, u3r_mug(u3A->key));
  }

  //  Write the header.
  {
    u3_uled led_u;

    led_u.mag_l = u3r_mug('g');
    led_u.kno_w = 163;

    if ( 0 == u3A->key ) {
      led_u.key_l = 0;
    } else {
      led_u.key_l = u3r_mug(u3A->key);

      c3_assert(!(led_u.key_l >> 31));
    }
    led_u.sal_l = sal_l;
    led_u.sev_l = u3A->sev_l;
    led_u.tno_l = 1;

    if ( sizeof(led_u) != write(fid_i, &led_u, sizeof(led_u)) ) {
      uL(fprintf(uH, "can't write record (%s)\n", ful_c));
      u3_lo_bail();
    }

    u3Z->lug_u.len_d = c3_wiseof(led_u);
  }

  //  Work through the boot events.
  u3_raft_work();
}
コード例 #6
0
ファイル: sist.c プロジェクト: wrmsr/urbit
/* u3_sist_pack(): write a blob to disk, transferring.
*/
c3_d
u3_sist_pack(c3_w tem_w, c3_w typ_w, c3_w* bob_w, c3_w len_w)
{
  u3_ulog* lug_u = &u3Z->lug_u;
  c3_d     tar_d;
  u3_ular  lar_u;

  tar_d = lug_u->len_d + len_w;

  lar_u.tem_w = tem_w;
  lar_u.typ_w = typ_w;
  lar_u.syn_w = u3r_mug((c3_w)tar_d);
  lar_u.mug_w = u3r_mug_both(u3r_mug_words(bob_w, len_w),
                               u3r_mug_both(u3r_mug(lar_u.tem_w),
                                              u3r_mug(lar_u.typ_w)));
  lar_u.ent_d = u3A->ent_d;
  u3A->ent_d++;
  lar_u.len_w = len_w;

  if ( -1 == lseek64(lug_u->fid_i, 4ULL * tar_d, SEEK_SET) ) {
    perror("lseek");
    uL(fprintf(uH, "sist_pack: seek failed\n"));
    c3_assert(0);
  }
  if ( sizeof(lar_u) != write(lug_u->fid_i, &lar_u, sizeof(lar_u)) ) {
    perror("write");
    uL(fprintf(uH, "sist_pack: write failed\n"));
    c3_assert(0);
  }
  if ( -1 == lseek64(lug_u->fid_i, 4ULL * lug_u->len_d, SEEK_SET) ) {
    perror("lseek");
    uL(fprintf(uH, "sist_pack: seek failed\n"));
    c3_assert(0);
  }
#if 0
  uL(fprintf(uH, "sist_pack: write %" PRIu64 ", %" PRIu64 ": lar ent %" PRIu64 ", len %d, mug %x\n",
                 lug_u->len_d,
                 tar_d,
                 lar_u.ent_d,
                 lar_u.len_w,
                 lar_u.mug_w));
#endif
  if ( (4 * len_w) != write(lug_u->fid_i, bob_w, (4 * len_w)) ) {
    perror("write");
    uL(fprintf(uH, "sist_pack: write failed\n"));
    c3_assert(0);
  }
  lug_u->len_d += (c3_d)(lar_u.len_w + c3_wiseof(lar_u));
  free(bob_w);

  //  Sync.  Or, what goes by sync.
  {
    fsync(lug_u->fid_i);    //  fsync is almost useless, F_FULLFSYNC too slow
#if defined(U3_OS_linux)
    fdatasync(lug_u->fid_i);
#elif defined(U3_OS_osx)
    fcntl(lug_u->fid_i, F_FULLFSYNC);
#elif defined(U3_OS_bsd)
    fsync(lug_u->fid_i);
#else
#   error "port: datasync"
#endif
  }

  return u3A->ent_d;
}