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 /** Finish #mdb_page_search() / #mdb_page_search_lowest().
  *   The cursor is at the root page, set up the rest of it.
  */
 static int
 mdb_page_search_root(MDB_cursor *mc, MDB_val *key, int flags)
 {
      MDB_page        *mp = mc->mc_pg[mc->mc_top];
      int rc;
      DKBUF;

      while (IS_BRANCH(mp)) {
              MDB_node        *node;
              indx_t          i;

              DPRINTF(("branch page %"Yu" has %u keys", mp->mp_pgno, NUMKEYS(mp)));
              /* Don't assert on branch pages in the FreeDB. We can get here
               * while in the process of rebalancing a FreeDB branch page; we must
               * let that proceed. ITS#8336
               */
              mdb_cassert(mc, !mc->mc_dbi || NUMKEYS(mp) > 1);
              DPRINTF(("found index 0 to page %"Yu, NODEPGNO(NODEPTR(mp, 0))));

              if (flags & (MDB_PS_FIRST|MDB_PS_LAST)) {
                      i = 0;
                      if (flags & MDB_PS_LAST) {
                              i = NUMKEYS(mp) - 1;
                              /* if already init'd, see if we're already in right place */
                              if (mc->mc_flags & C_INITIALIZED) {
                                      if (mc->mc_ki[mc->mc_top] == i) {
                                              mc->mc_top = mc->mc_snum++;
                                              mp = mc->mc_pg[mc->mc_top];
                                              goto ready;
                                      }
                              }
                      }
              } else {
                      int      exact;
                      node = mdb_node_search(mc, key, &exact);
                      if (node == NULL)
                              i = NUMKEYS(mp) - 1;
                      else {
                              i = mc->mc_ki[mc->mc_top];
                              if (!exact) {
                                      mdb_cassert(mc, i > 0);
                                      i--;
                              }
                      }
                      DPRINTF(("following index %u for key [%s]", i, DKEY(key)));
              }

              mdb_cassert(mc, i < NUMKEYS(mp));
              node = NODEPTR(mp, i);

              if ((rc = mdb_page_get(mc, NODEPGNO(node), &mp, NULL)) != 0)
                      return rc;

              mc->mc_ki[mc->mc_top] = i;
              if ((rc = mdb_cursor_push(mc, mp)))
                      return rc;

 ready:
              if (flags & MDB_PS_MODIFY) {
                      if ((rc = mdb_page_touch(mc)) != 0)
                              return rc;
                      mp = mc->mc_pg[mc->mc_top];
              }
      }

      if (!IS_LEAF(mp)) {
              DPRINTF(("internal error, index points to a %02X page!?",
                  mp->mp_flags));
              mc->mc_txn->mt_flags |= MDB_TXN_ERROR;
              return MDB_CORRUPTED;
      }

      DPRINTF(("found leaf page %"Yu" for key [%s]", mp->mp_pgno,
          key ? DKEY(key) : "null"));
      mc->mc_flags |= C_INITIALIZED;
      mc->mc_flags &= ~C_EOF;

      return MDB_SUCCESS;
 }