Add more documentation to microdesc.c, plus another assert.

  return 0;

}

/** DOCDOC */

/** By default, we remove any microdescriptors that have gone at least this

 * long without appearing in a current consensus. */

#define TOLERATE_MICRODESC_AGE (7*24*60*60)

/** DOCDOC */

/** Remove all microdescriptors from <b>cache</b> that haven't been listed for

 * a long time.  Does not rebuild the cache on disk.  If <b>cutoff</b> is

 * positive, specifically remove microdescriptors that have been unlisted

 * since <b>cutoff</b>.  If <b>force</b> is true, remove microdescriptors even

 * if we have no current live microdescriptor consensus.

 */

void

microdesc_cache_clean(microdesc_cache_t *cache, time_t cutoff, int force)

{

  size_t bytes_dropped = 0;

  time_t now = time(NULL);

  /* If we don't know a consensus, never believe last_listed values */

  /* If we don't know a live consensus, don't believe last_listed values: we

   * might be starting up after being down for a while. */

  if (! force &&

      ! networkstatus_get_reasonably_live_consensus(now, FLAV_MICRODESC))

      return;

  log_info(LD_DIR, "Rebuilding the microdescriptor cache...");

  /* Remove dead descriptors */

  microdesc_cache_clean(cache, 0/*cutoff*/, 0/*force*/);

  /* Calculate starting disk usage */

  orig_size = (int)(cache->cache_content ? cache->cache_content->size : 0);

  orig_size += (int)cache->journal_len;

      /* log?  return -1?  die?  coredump the universe? */

      continue;

    }

    tor_assert(((size_t)size) == annotation_len + md->bodylen);

    md->off = off + annotation_len;

    off += size;

    if (md->saved_location != SAVED_IN_CACHE) {

  return result;

}

/** DOCDOC */

/** Launch download requests for mircodescriptors as appropriate.

 *

 * Specifically, we should launch download requests if we are configured to

 * download mirodescriptors, and there are some microdescriptors listed the

 * current microdesc consensus that we don't have, and either we never asked

 * for them, or we failed to download them but we're willing to retry.

 */

void

update_microdesc_downloads(time_t now)

{

  smartlist_free(missing);

}

/** DOCDOC */

/** For every microdescriptor listed in the current microdecriptor consensus,

 * update its last_listed field to be at least as recent as the publication

 * time of the current microdescriptor consensus.

 */

void

update_microdescs_from_networkstatus(time_t now)

{