<?php // This file is part of BOINC. // http://boinc.berkeley.edu // Copyright (C) 2008 University of California // // BOINC is free software; you can redistribute it and/or modify it // under the terms of the GNU Lesser General Public License // as published by the Free Software Foundation, // either version 3 of the License, or (at your option) any later version. // // BOINC is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. // See the GNU Lesser General Public License for more details. // // You should have received a copy of the GNU Lesser General Public License // along with BOINC. If not, see <http://www.gnu.org/licenses/>. // An iterator represents a user's position in a course. // Its state is stored in the database, // and the course may change underneath it. // // A state in a course is described by an associative array // mapping logical names to state structures. // Typically this includes the logical name of the current child // and info such as a sequence index. // This is kind of like a "call stack", // except that it can contain units not currently active. // class BoltIter { public $top; // topmost unit public $state; public $xset; // exercise set, if any // the following are temps public $item; // current item public $frac_done; // fraction done function __construct($top) { $this->top = $top; $this->state = array(); } function decode_state($encoded_state) { $this->state = unserialize($encoded_state); } function encode_state() { return serialize($this->state); } // get current item and fraction done // function at() { $this->xset = null; $this->top->walk($this, false, $this->frac_done); } // move to the next item, and return it in $this->item // (null if course finished) // function next() { $this->top->walk($this, true, $this->frac_done); } } function enum_course($course) { $iter = new BoltIter($course); while (1) { $x = $iter->at(); if (!$x) break; echo "at: $x->url\n"; $x = $iter->next(); if (!$x) break; echo "next: $x->filename\n"; } echo "course over\n"; } ?>