lib/datalib.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * Library of functions for database manipulation.
  19  *
  20  * Other main libraries:
  21  * - weblib.php - functions that produce web output
  22  * - moodlelib.php - general-purpose Moodle functions
  23  *
  24  * @package    core
  25  * @copyright  1999 onwards Martin Dougiamas  {@link http://moodle.com}
  26  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  27  */
  28
  29 defined('MOODLE_INTERNAL') || die();
  30
  31 /**
  32  * The maximum courses in a category
  33  * MAX_COURSES_IN_CATEGORY * MAX_COURSE_CATEGORIES must not be more than max integer!
  34  */
  35 define('MAX_COURSES_IN_CATEGORY', 10000);
  36
  37 /**
  38   * The maximum number of course categories
  39   * MAX_COURSES_IN_CATEGORY * MAX_COURSE_CATEGORIES must not be more than max integer!
  40   */
  41 define('MAX_COURSE_CATEGORIES', 10000);
  42
  43 /**
  44  * Number of seconds to wait before updating lastaccess information in DB.
  45  */
  46 define('LASTACCESS_UPDATE_SECS', 60);
  47
  48 /**
  49  * Returns $user object of the main admin user
  50  *
  51  * @static stdClass $mainadmin
  52  * @return stdClass {@link $USER} record from DB, false if not found
  53  */
  54 function get_admin() {
  55     global $CFG, $DB;
  56
  57     static $mainadmin = null;
  58
  59     if (isset($mainadmin)) {
  60         return clone($mainadmin);
  61     }
  62
  63     if (empty($CFG->siteadmins)) {  // Should not happen on an ordinary site
  64         return false;
  65     }
  66
  67     foreach (explode(',', $CFG->siteadmins) as $id) {
  68         if ($user = $DB->get_record('user', array('id'=>$id, 'deleted'=>0))) {
  69             $mainadmin = $user;
  70             break;
  71         }
  72     }
  73
  74     if ($mainadmin) {
  75         return clone($mainadmin);
  76     } else {
  77         // this should not happen
  78         return false;
  79     }
  80 }
  81
  82 /**
  83  * Returns list of all admins, using 1 DB query
  84  *
  85  * @return array
  86  */
  87 function get_admins() {
  88     global $DB, $CFG;
  89
  90     if (empty($CFG->siteadmins)) {  // Should not happen on an ordinary site
  91         return array();
  92     }
  93
  94     $sql = "SELECT u.*
  95               FROM {user} u
  96              WHERE u.deleted = 0 AND u.id IN ($CFG->siteadmins)";
  97
  98     return $DB->get_records_sql($sql);
  99 }
 100
 101 /**
 102  * Search through course users
 103  *
 104  * If $coursid specifies the site course then this function searches
 105  * through all undeleted and confirmed users
 106  *
 107  * @global object
 108  * @uses SITEID
 109  * @uses SQL_PARAMS_NAMED
 110  * @uses CONTEXT_COURSE
 111  * @param int $courseid The course in question.
 112  * @param int $groupid The group in question.
 113  * @param string $searchtext The string to search for
 114  * @param string $sort A field to sort by
 115  * @param array $exceptions A list of IDs to ignore, eg 2,4,5,8,9,10
 116  * @return array
 117  */
 118 function search_users($courseid, $groupid, $searchtext, $sort='', array $exceptions=null) {
 119     global $DB;
 120
 121     $fullname  = $DB->sql_fullname('u.firstname', 'u.lastname');
 122
 123     if (!empty($exceptions)) {
 124         list($exceptions, $params) = $DB->get_in_or_equal($exceptions, SQL_PARAMS_NAMED, 'ex', false);
 125         $except = "AND u.id $exceptions";
 126     } else {
 127         $except = "";
 128         $params = array();
 129     }
 130
 131     if (!empty($sort)) {
 132         $order = "ORDER BY $sort";
 133     } else {
 134         $order = "";
 135     }
 136
 137     $select = "u.deleted = 0 AND u.confirmed = 1 AND (".$DB->sql_like($fullname, ':search1', false)." OR ".$DB->sql_like('u.email', ':search2', false).")";
 138     $params['search1'] = "%$searchtext%";
 139     $params['search2'] = "%$searchtext%";
 140
 141     if (!$courseid or $courseid == SITEID) {
 142         $sql = "SELECT u.id, u.firstname, u.lastname, u.email
 143                   FROM {user} u
 144                  WHERE $select
 145                        $except
 146                 $order";
 147         return $DB->get_records_sql($sql, $params);
 148
 149     } else {
 150         if ($groupid) {
 151             $sql = "SELECT u.id, u.firstname, u.lastname, u.email
 152                       FROM {user} u
 153                       JOIN {groups_members} gm ON gm.userid = u.id
 154                      WHERE $select AND gm.groupid = :groupid
 155                            $except
 156                      $order";
 157             $params['groupid'] = $groupid;
 158             return $DB->get_records_sql($sql, $params);
 159
 160         } else {
 161             $context = get_context_instance(CONTEXT_COURSE, $courseid);
 162             $contextlists = get_related_contexts_string($context);
 163
 164             $sql = "SELECT u.id, u.firstname, u.lastname, u.email
 165                       FROM {user} u
 166                       JOIN {role_assignments} ra ON ra.userid = u.id
 167                      WHERE $select AND ra.contextid $contextlists
 168                            $except
 169                     $order";
 170             return $DB->get_records_sql($sql, $params);
 171         }
 172     }
 173 }
 174
 175 /**
 176  * Returns a subset of users
 177  *
 178  * @global object
 179  * @uses DEBUG_DEVELOPER
 180  * @uses SQL_PARAMS_NAMED
 181  * @param bool $get If false then only a count of the records is returned
 182  * @param string $search A simple string to search for
 183  * @param bool $confirmed A switch to allow/disallow unconfirmed users
 184  * @param array $exceptions A list of IDs to ignore, eg 2,4,5,8,9,10
 185  * @param string $sort A SQL snippet for the sorting criteria to use
 186  * @param string $firstinitial Users whose first name starts with $firstinitial
 187  * @param string $lastinitial Users whose last name starts with $lastinitial
 188  * @param string $page The page or records to return
 189  * @param string $recordsperpage The number of records to return per page
 190  * @param string $fields A comma separated list of fields to be returned from the chosen table.
 191  * @return array|int|bool  {@link $USER} records unless get is false in which case the integer count of the records found is returned.
 192   *                        False is returned if an error is encountered.
 193  */
 194 function get_users($get=true, $search='', $confirmed=false, array $exceptions=null, $sort='firstname ASC',
 195                    $firstinitial='', $lastinitial='', $page='', $recordsperpage='', $fields='*', $extraselect='', array $extraparams=null) {
 196     global $DB, $CFG;
 197
 198     if ($get && !$recordsperpage) {
 199         debugging('Call to get_users with $get = true no $recordsperpage limit. ' .
 200                 'On large installations, this will probably cause an out of memory error. ' .
 201                 'Please think again and change your code so that it does not try to ' .
 202                 'load so much data into memory.', DEBUG_DEVELOPER);
 203     }
 204
 205     $fullname  = $DB->sql_fullname();
 206
 207     $select = " id <> :guestid AND deleted = 0";
 208     $params = array('guestid'=>$CFG->siteguest);
 209
 210     if (!empty($search)){
 211         $search = trim($search);
 212         $select .= " AND (".$DB->sql_like($fullname, ':search1', false)." OR ".$DB->sql_like('email', ':search2', false)." OR username = :search3)";
 213         $params['search1'] = "%$search%";
 214         $params['search2'] = "%$search%";
 215         $params['search3'] = "$search";
 216     }
 217
 218     if ($confirmed) {
 219         $select .= " AND confirmed = 1";
 220     }
 221
 222     if ($exceptions) {
 223         list($exceptions, $eparams) = $DB->get_in_or_equal($exceptions, SQL_PARAMS_NAMED, 'ex', false);
 224         $params = $params + $eparams;
 225         $select .= " AND id $exceptions";
 226     }
 227
 228     if ($firstinitial) {
 229         $select .= " AND ".$DB->sql_like('firstname', ':fni', false, false);
 230         $params['fni'] = "$firstinitial%";
 231     }
 232     if ($lastinitial) {
 233         $select .= " AND ".$DB->sql_like('lastname', ':lni', false, false);
 234         $params['lni'] = "$lastinitial%";
 235     }
 236
 237     if ($extraselect) {
 238         $select .= " AND $extraselect";
 239         $params = $params + (array)$extraparams;
 240     }
 241
 242     if ($get) {
 243         return $DB->get_records_select('user', $select, $params, $sort, $fields, $page, $recordsperpage);
 244     } else {
 245         return $DB->count_records_select('user', $select, $params);
 246     }
 247 }
 248
 249
 250 /**
 251  * @todo Finish documenting this function
 252  *
 253  * @param string $sort An SQL field to sort by
 254  * @param string $dir The sort direction ASC|DESC
 255  * @param int $page The page or records to return
 256  * @param int $recordsperpage The number of records to return per page
 257  * @param string $search A simple string to search for
 258  * @param string $firstinitial Users whose first name starts with $firstinitial
 259  * @param string $lastinitial Users whose last name starts with $lastinitial
 260  * @param string $extraselect An additional SQL select statement to append to the query
 261  * @param array $extraparams Additional parameters to use for the above $extraselect
 262  * @param object $extracontext If specified, will include user 'extra fields'
 263  *   as appropriate for current user and given context
 264  * @return array Array of {@link $USER} records
 265  */
 266 function get_users_listing($sort='lastaccess', $dir='ASC', $page=0, $recordsperpage=0,
 267                            $search='', $firstinitial='', $lastinitial='', $extraselect='',
 268                            array $extraparams=null, $extracontext = null) {
 269     global $DB;
 270
 271     $fullname  = $DB->sql_fullname();
 272
 273     $select = "deleted <> 1";
 274     $params = array();
 275
 276     if (!empty($search)) {
 277         $search = trim($search);
 278         $select .= " AND (". $DB->sql_like($fullname, ':search1', false, false).
 279                    " OR ". $DB->sql_like('email', ':search2', false, false).
 280                    " OR username = :search3)";
 281         $params['search1'] = "%$search%";
 282         $params['search2'] = "%$search%";
 283         $params['search3'] = "$search";
 284     }
 285
 286     if ($firstinitial) {
 287         $select .= " AND ". $DB->sql_like('firstname', ':fni', false, false);
 288         $params['fni'] = "$firstinitial%";
 289     }
 290     if ($lastinitial) {
 291         $select .= " AND ". $DB->sql_like('lastname', ':lni', false, false);
 292         $params['lni'] = "$lastinitial%";
 293     }
 294
 295     if ($extraselect) {
 296         $select .= " AND $extraselect";
 297         $params = $params + (array)$extraparams;
 298     }
 299
 300     if ($sort) {
 301         $sort = " ORDER BY $sort $dir";
 302     }
 303
 304     // If a context is specified, get extra user fields that the current user
 305     // is supposed to see.
 306     $extrafields = '';
 307     if ($extracontext) {
 308         $extrafields = get_extra_user_fields_sql($extracontext, '', '',
 309                 array('id', 'username', 'email', 'firstname', 'lastname', 'city', 'country',
 310                 'lastaccess', 'confirmed', 'mnethostid'));
 311     }
 312
 313     // warning: will return UNCONFIRMED USERS
 314     return $DB->get_records_sql("SELECT id, username, email, firstname, lastname, city, country,
 315                                         lastaccess, confirmed, mnethostid, suspended $extrafields
 316                                    FROM {user}
 317                                   WHERE $select
 318                                   $sort", $params, $page, $recordsperpage);
 319
 320 }
 321
 322
 323 /**
 324  * Full list of users that have confirmed their accounts.
 325  *
 326  * @global object
 327  * @return array of unconfirmed users
 328  */
 329 function get_users_confirmed() {
 330     global $DB, $CFG;
 331     return $DB->get_records_sql("SELECT *
 332                                    FROM {user}
 333                                   WHERE confirmed = 1 AND deleted = 0 AND id <> ?", array($CFG->siteguest));
 334 }
 335
 336
 337 /// OTHER SITE AND COURSE FUNCTIONS /////////////////////////////////////////////
 338
 339
 340 /**
 341  * Returns $course object of the top-level site.
 342  *
 343  * @return object A {@link $COURSE} object for the site, exception if not found
 344  */
 345 function get_site() {
 346     global $SITE, $DB;
 347
 348     if (!empty($SITE->id)) {   // We already have a global to use, so return that
 349         return $SITE;
 350     }
 351
 352     if ($course = $DB->get_record('course', array('category'=>0))) {
 353         return $course;
 354     } else {
 355         // course table exists, but the site is not there,
 356         // unfortunately there is no automatic way to recover
 357         throw new moodle_exception('nosite', 'error');
 358     }
 359 }
 360
 361 /**
 362  * Returns list of courses, for whole site, or category
 363  *
 364  * Returns list of courses, for whole site, or category
 365  * Important: Using c.* for fields is extremely expensive because
 366  *            we are using distinct. You almost _NEVER_ need all the fields
 367  *            in such a large SELECT
 368  *
 369  * @global object
 370  * @global object
 371  * @global object
 372  * @uses CONTEXT_COURSE
 373  * @param string|int $categoryid Either a category id or 'all' for everything
 374  * @param string $sort A field and direction to sort by
 375  * @param string $fields The additional fields to return
 376  * @return array Array of courses
 377  */
 378 function get_courses($categoryid="all", $sort="c.sortorder ASC", $fields="c.*") {
 379
 380     global $USER, $CFG, $DB;
 381
 382     $params = array();
 383
 384     if ($categoryid !== "all" && is_numeric($categoryid)) {
 385         $categoryselect = "WHERE c.category = :catid";
 386         $params['catid'] = $categoryid;
 387     } else {
 388         $categoryselect = "";
 389     }
 390
 391     if (empty($sort)) {
 392         $sortstatement = "";
 393     } else {
 394         $sortstatement = "ORDER BY $sort";
 395     }
 396
 397     $visiblecourses = array();
 398
 399     list($ccselect, $ccjoin) = context_instance_preload_sql('c.id', CONTEXT_COURSE, 'ctx');
 400
 401     $sql = "SELECT $fields $ccselect
 402               FROM {course} c
 403            $ccjoin
 404               $categoryselect
 405               $sortstatement";
 406
 407     // pull out all course matching the cat
 408     if ($courses = $DB->get_records_sql($sql, $params)) {
 409
 410         // loop throught them
 411         foreach ($courses as $course) {
 412             context_instance_preload($course);
 413             if (isset($course->visible) && $course->visible <= 0) {
 414                 // for hidden courses, require visibility check
 415                 if (has_capability('moodle/course:viewhiddencourses', get_context_instance(CONTEXT_COURSE, $course->id))) {
 416                     $visiblecourses [$course->id] = $course;
 417                 }
 418             } else {
 419                 $visiblecourses [$course->id] = $course;
 420             }
 421         }
 422     }
 423     return $visiblecourses;
 424 }
 425
 426
 427 /**
 428  * Returns list of courses, for whole site, or category
 429  *
 430  * Similar to get_courses, but allows paging
 431  * Important: Using c.* for fields is extremely expensive because
 432  *            we are using distinct. You almost _NEVER_ need all the fields
 433  *            in such a large SELECT
 434  *
 435  * @global object
 436  * @global object
 437  * @global object
 438  * @uses CONTEXT_COURSE
 439  * @param string|int $categoryid Either a category id or 'all' for everything
 440  * @param string $sort A field and direction to sort by
 441  * @param string $fields The additional fields to return
 442  * @param int $totalcount Reference for the number of courses
 443  * @param string $limitfrom The course to start from
 444  * @param string $limitnum The number of courses to limit to
 445  * @return array Array of courses
 446  */
 447 function get_courses_page($categoryid="all", $sort="c.sortorder ASC", $fields="c.*",
 448                           &$totalcount, $limitfrom="", $limitnum="") {
 449     global $USER, $CFG, $DB;
 450
 451     $params = array();
 452
 453     $categoryselect = "";
 454     if ($categoryid != "all" && is_numeric($categoryid)) {
 455         $categoryselect = "WHERE c.category = :catid";
 456         $params['catid'] = $categoryid;
 457     } else {
 458         $categoryselect = "";
 459     }
 460
 461     list($ccselect, $ccjoin) = context_instance_preload_sql('c.id', CONTEXT_COURSE, 'ctx');
 462
 463     $totalcount = 0;
 464     if (!$limitfrom) {
 465         $limitfrom = 0;
 466     }
 467     $visiblecourses = array();
 468
 469     $sql = "SELECT $fields $ccselect
 470               FROM {course} c
 471               $ccjoin
 472            $categoryselect
 473           ORDER BY $sort";
 474
 475     // pull out all course matching the cat
 476     $rs = $DB->get_recordset_sql($sql, $params);
 477     // iteration will have to be done inside loop to keep track of the limitfrom and limitnum
 478     foreach($rs as $course) {
 479         context_instance_preload($course);
 480         if ($course->visible <= 0) {
 481             // for hidden courses, require visibility check
 482             if (has_capability('moodle/course:viewhiddencourses', get_context_instance(CONTEXT_COURSE, $course->id))) {
 483                 $totalcount++;
 484                 if ($totalcount > $limitfrom && (!$limitnum or count($visiblecourses) < $limitnum)) {
 485                     $visiblecourses [$course->id] = $course;
 486                 }
 487             }
 488         } else {
 489             $totalcount++;
 490             if ($totalcount > $limitfrom && (!$limitnum or count($visiblecourses) < $limitnum)) {
 491                 $visiblecourses [$course->id] = $course;
 492             }
 493         }
 494     }
 495     $rs->close();
 496     return $visiblecourses;
 497 }
 498
 499 /**
 500  * Retrieve course records with the course managers and other related records
 501  * that we need for print_course(). This allows print_courses() to do its job
 502  * in a constant number of DB queries, regardless of the number of courses,
 503  * role assignments, etc.
 504  *
 505  * The returned array is indexed on c.id, and each course will have
 506  * - $course->managers - array containing RA objects that include a $user obj
 507  *                       with the minimal fields needed for fullname()
 508  *
 509  * @global object
 510  * @global object
 511  * @global object
 512  * @uses CONTEXT_COURSE
 513  * @uses CONTEXT_SYSTEM
 514  * @uses CONTEXT_COURSECAT
 515  * @uses SITEID
 516  * @param int|string $categoryid Either the categoryid for the courses or 'all'
 517  * @param string $sort A SQL sort field and direction
 518  * @param array $fields An array of additional fields to fetch
 519  * @return array
 520  */
 521 function get_courses_wmanagers($categoryid=0, $sort="c.sortorder ASC", $fields=array()) {
 522     /*
 523      * The plan is to
 524      *
 525      * - Grab the courses JOINed w/context
 526      *
 527      * - Grab the interesting course-manager RAs
 528      *   JOINed with a base user obj and add them to each course
 529      *
 530      * So as to do all the work in 2 DB queries. The RA+user JOIN
 531      * ends up being pretty expensive if it happens over _all_
 532      * courses on a large site. (Are we surprised!?)
 533      *
 534      * So this should _never_ get called with 'all' on a large site.
 535      *
 536      */
 537     global $USER, $CFG, $DB;
 538
 539     $params = array();
 540     $allcats = false; // bool flag
 541     if ($categoryid === 'all') {
 542         $categoryclause   = '';
 543         $allcats = true;
 544     } elseif (is_numeric($categoryid)) {
 545         $categoryclause = "c.category = :catid";
 546         $params['catid'] = $categoryid;
 547     } else {
 548         debugging("Could not recognise categoryid = $categoryid");
 549         $categoryclause = '';
 550     }
 551
 552     $basefields = array('id', 'category', 'sortorder',
 553                         'shortname', 'fullname', 'idnumber',
 554                         'startdate', 'visible',
 555                         'newsitems', 'groupmode', 'groupmodeforce');
 556
 557     if (!is_null($fields) && is_string($fields)) {
 558         if (empty($fields)) {
 559             $fields = $basefields;
 560         } else {
 561             // turn the fields from a string to an array that
 562             // get_user_courses_bycap() will like...
 563             $fields = explode(',',$fields);
 564             $fields = array_map('trim', $fields);
 565             $fields = array_unique(array_merge($basefields, $fields));
 566         }
 567     } elseif (is_array($fields)) {
 568         $fields = array_merge($basefields,$fields);
 569     }
 570     $coursefields = 'c.' .join(',c.', $fields);
 571
 572     if (empty($sort)) {
 573         $sortstatement = "";
 574     } else {
 575         $sortstatement = "ORDER BY $sort";
 576     }
 577
 578     $where = 'WHERE c.id != ' . SITEID;
 579     if ($categoryclause !== ''){
 580         $where = "$where AND $categoryclause";
 581     }
 582
 583     // pull out all courses matching the cat
 584     list($ccselect, $ccjoin) = context_instance_preload_sql('c.id', CONTEXT_COURSE, 'ctx');
 585     $sql = "SELECT $coursefields $ccselect
 586               FROM {course} c
 587            $ccjoin
 588                $where
 589                $sortstatement";
 590
 591     $catpaths = array();
 592     $catpath  = NULL;
 593     if ($courses = $DB->get_records_sql($sql, $params)) {
 594         // loop on courses materialising
 595         // the context, and prepping data to fetch the
 596         // managers efficiently later...
 597         foreach ($courses as $k => $course) {
 598             context_instance_preload($course);
 599             $coursecontext = get_context_instance(CONTEXT_COURSE, $course->id);
 600             $courses[$k] = $course;
 601             $courses[$k]->managers = array();
 602             if ($allcats === false) {
 603                 // single cat, so take just the first one...
 604                 if ($catpath === NULL) {
 605                     $catpath = preg_replace(':/\d+$:', '', $coursecontext->path);
 606                 }
 607             } else {
 608                 // chop off the contextid of the course itself
 609                 // like dirname() does...
 610                 $catpaths[] = preg_replace(':/\d+$:', '', $coursecontext->path);
 611             }
 612         }
 613     } else {
 614         return array(); // no courses!
 615     }
 616
 617     $CFG->coursecontact = trim($CFG->coursecontact);
 618     if (empty($CFG->coursecontact)) {
 619         return $courses;
 620     }
 621
 622     $managerroles = explode(',', $CFG->coursecontact);
 623     $catctxids = '';
 624     if (count($managerroles)) {
 625         if ($allcats === true) {
 626             $catpaths  = array_unique($catpaths);
 627             $ctxids = array();
 628             foreach ($catpaths as $cpath) {
 629                 $ctxids = array_merge($ctxids, explode('/',substr($cpath,1)));
 630             }
 631             $ctxids = array_unique($ctxids);
 632             $catctxids = implode( ',' , $ctxids);
 633             unset($catpaths);
 634             unset($cpath);
 635         } else {
 636             // take the ctx path from the first course
 637             // as all categories will be the same...
 638             $catpath = substr($catpath,1);
 639             $catpath = preg_replace(':/\d+$:','',$catpath);
 640             $catctxids = str_replace('/',',',$catpath);
 641         }
 642         if ($categoryclause !== '') {
 643             $categoryclause = "AND $categoryclause";
 644         }
 645         /*
 646          * Note: Here we use a LEFT OUTER JOIN that can
 647          * "optionally" match to avoid passing a ton of context
 648          * ids in an IN() clause. Perhaps a subselect is faster.
 649          *
 650          * In any case, this SQL is not-so-nice over large sets of
 651          * courses with no $categoryclause.
 652          *
 653          */
 654         $sql = "SELECT ctx.path, ctx.instanceid, ctx.contextlevel,
 655                        r.id AS roleid, r.name as rolename,
 656                        u.id AS userid, u.firstname, u.lastname
 657                   FROM {role_assignments} ra
 658                   JOIN {context} ctx ON ra.contextid = ctx.id
 659                   JOIN {user} u ON ra.userid = u.id
 660                   JOIN {role} r ON ra.roleid = r.id
 661                   LEFT OUTER JOIN {course} c
 662                        ON (ctx.instanceid=c.id AND ctx.contextlevel=".CONTEXT_COURSE.")
 663                 WHERE ( c.id IS NOT NULL";
 664         // under certain conditions, $catctxids is NULL
 665         if($catctxids == NULL){
 666             $sql .= ") ";
 667         }else{
 668             $sql .= " OR ra.contextid  IN ($catctxids) )";
 669         }
 670
 671         $sql .= "AND ra.roleid IN ({$CFG->coursecontact})
 672                       $categoryclause
 673                 ORDER BY r.sortorder ASC, ctx.contextlevel ASC, ra.sortorder ASC";
 674         $rs = $DB->get_recordset_sql($sql, $params);
 675
 676         // This loop is fairly stupid as it stands - might get better
 677         // results doing an initial pass clustering RAs by path.
 678         foreach($rs as $ra) {
 679             $user = new stdClass;
 680             $user->id        = $ra->userid;    unset($ra->userid);
 681             $user->firstname = $ra->firstname; unset($ra->firstname);
 682             $user->lastname  = $ra->lastname;  unset($ra->lastname);
 683             $ra->user = $user;
 684             if ($ra->contextlevel == CONTEXT_SYSTEM) {
 685                 foreach ($courses as $k => $course) {
 686                     $courses[$k]->managers[] = $ra;
 687                 }
 688             } else if ($ra->contextlevel == CONTEXT_COURSECAT) {
 689                 if ($allcats === false) {
 690                     // It always applies
 691                     foreach ($courses as $k => $course) {
 692                         $courses[$k]->managers[] = $ra;
 693                     }
 694                 } else {
 695                     foreach ($courses as $k => $course) {
 696                         $coursecontext = get_context_instance(CONTEXT_COURSE, $course->id);
 697                         // Note that strpos() returns 0 as "matched at pos 0"
 698                         if (strpos($coursecontext->path, $ra->path.'/') === 0) {
 699                             // Only add it to subpaths
 700                             $courses[$k]->managers[] = $ra;
 701                         }
 702                     }
 703                 }
 704             } else { // course-level
 705                 if (!array_key_exists($ra->instanceid, $courses)) {
 706                     //this course is not in a list, probably a frontpage course
 707                     continue;
 708                 }
 709                 $courses[$ra->instanceid]->managers[] = $ra;
 710             }
 711         }
 712         $rs->close();
 713     }
 714
 715     return $courses;
 716 }
 717
 718 /**
 719  * A list of courses that match a search
 720  *
 721  * @global object
 722  * @global object
 723  * @param array $searchterms An array of search criteria
 724  * @param string $sort A field and direction to sort by
 725  * @param int $page The page number to get
 726  * @param int $recordsperpage The number of records per page
 727  * @param int $totalcount Passed in by reference.
 728  * @return object {@link $COURSE} records
 729  */
 730 function get_courses_search($searchterms, $sort='fullname ASC', $page=0, $recordsperpage=50, &$totalcount) {
 731     global $CFG, $DB;
 732
 733     if ($DB->sql_regex_supported()) {
 734         $REGEXP    = $DB->sql_regex(true);
 735         $NOTREGEXP = $DB->sql_regex(false);
 736     }
 737
 738     $searchcond = array();
 739     $params     = array();
 740     $i = 0;
 741
 742     // Thanks Oracle for your non-ansi concat and type limits in coalesce. MDL-29912
 743     if ($DB->get_dbfamily() == 'oracle') {
 744         $concat = $DB->sql_concat('c.summary', "' '", 'c.fullname', "' '", 'c.idnumber', "' '", 'c.shortname');
 745     } else {
 746         $concat = $DB->sql_concat("COALESCE(c.summary, '". $DB->sql_empty() ."')", "' '", 'c.fullname', "' '", 'c.idnumber', "' '", 'c.shortname');
 747     }
 748
 749     foreach ($searchterms as $searchterm) {
 750         $i++;
 751
 752         $NOT = false; /// Initially we aren't going to perform NOT LIKE searches, only MSSQL and Oracle
 753                    /// will use it to simulate the "-" operator with LIKE clause
 754
 755     /// Under Oracle and MSSQL, trim the + and - operators and perform
 756     /// simpler LIKE (or NOT LIKE) queries
 757         if (!$DB->sql_regex_supported()) {
 758             if (substr($searchterm, 0, 1) == '-') {
 759                 $NOT = true;
 760             }
 761             $searchterm = trim($searchterm, '+-');
 762         }
 763
 764         // TODO: +- may not work for non latin languages
 765
 766         if (substr($searchterm,0,1) == '+') {
 767             $searchterm = trim($searchterm, '+-');
 768             $searchterm = preg_quote($searchterm, '|');
 769             $searchcond[] = "$concat $REGEXP :ss$i";
 770             $params['ss'.$i] = "(^|[^a-zA-Z0-9])$searchterm([^a-zA-Z0-9]|$)";
 771
 772         } else if (substr($searchterm,0,1) == "-") {
 773             $searchterm = trim($searchterm, '+-');
 774             $searchterm = preg_quote($searchterm, '|');
 775             $searchcond[] = "$concat $NOTREGEXP :ss$i";
 776             $params['ss'.$i] = "(^|[^a-zA-Z0-9])$searchterm([^a-zA-Z0-9]|$)";
 777
 778         } else {
 779             $searchcond[] = $DB->sql_like($concat,":ss$i", false, true, $NOT);
 780             $params['ss'.$i] = "%$searchterm%";
 781         }
 782     }
 783
 784     if (empty($searchcond)) {
 785         $totalcount = 0;
 786         return array();
 787     }
 788
 789     $searchcond = implode(" AND ", $searchcond);
 790
 791     $courses = array();
 792     $c = 0; // counts how many visible courses we've seen
 793
 794     // Tiki pagination
 795     $limitfrom = $page * $recordsperpage;
 796     $limitto   = $limitfrom + $recordsperpage;
 797
 798     list($ccselect, $ccjoin) = context_instance_preload_sql('c.id', CONTEXT_COURSE, 'ctx');
 799     $sql = "SELECT c.* $ccselect
 800               FROM {course} c
 801            $ccjoin
 802              WHERE $searchcond AND c.id <> ".SITEID."
 803           ORDER BY $sort";
 804
 805     $rs = $DB->get_recordset_sql($sql, $params);
 806     foreach($rs as $course) {
 807         context_instance_preload($course);
 808         $coursecontext = get_context_instance(CONTEXT_COURSE, $course->id);
 809         if ($course->visible || has_capability('moodle/course:viewhiddencourses', $coursecontext)) {
 810             // Don't exit this loop till the end
 811             // we need to count all the visible courses
 812             // to update $totalcount
 813             if ($c >= $limitfrom && $c < $limitto) {
 814                 $courses[$course->id] = $course;
 815             }
 816             $c++;
 817         }
 818     }
 819     $rs->close();
 820
 821     // our caller expects 2 bits of data - our return
 822     // array, and an updated $totalcount
 823     $totalcount = $c;
 824     return $courses;
 825 }
 826
 827
 828 /**
 829  * Returns a sorted list of categories. Each category object has a context
 830  * property that is a context object.
 831  *
 832  * When asking for $parent='none' it will return all the categories, regardless
 833  * of depth. Wheen asking for a specific parent, the default is to return
 834  * a "shallow" resultset. Pass false to $shallow and it will return all
 835  * the child categories as well.
 836  *
 837  * @global object
 838  * @uses CONTEXT_COURSECAT
 839  * @param string $parent The parent category if any
 840  * @param string $sort the sortorder
 841  * @param bool   $shallow - set to false to get the children too
 842  * @return array of categories
 843  */
 844 function get_categories($parent='none', $sort=NULL, $shallow=true) {
 845     global $DB;
 846
 847     if ($sort === NULL) {
 848         $sort = 'ORDER BY cc.sortorder ASC';
 849     } elseif ($sort ==='') {
 850         // leave it as empty
 851     } else {
 852         $sort = "ORDER BY $sort";
 853     }
 854
 855     list($ccselect, $ccjoin) = context_instance_preload_sql('cc.id', CONTEXT_COURSECAT, 'ctx');
 856
 857     if ($parent === 'none') {
 858         $sql = "SELECT cc.* $ccselect
 859                   FROM {course_categories} cc
 860                $ccjoin
 861                 $sort";
 862         $params = array();
 863
 864     } elseif ($shallow) {
 865         $sql = "SELECT cc.* $ccselect
 866                   FROM {course_categories} cc
 867                $ccjoin
 868                  WHERE cc.parent=?
 869                 $sort";
 870         $params = array($parent);
 871
 872     } else {
 873         $sql = "SELECT cc.* $ccselect
 874                   FROM {course_categories} cc
 875                $ccjoin
 876                   JOIN {course_categories} ccp
 877                        ON ((cc.parent = ccp.id) OR (cc.path LIKE ".$DB->sql_concat('ccp.path',"'/%'")."))
 878                  WHERE ccp.id=?
 879                 $sort";
 880         $params = array($parent);
 881     }
 882     $categories = array();
 883
 884     $rs = $DB->get_recordset_sql($sql, $params);
 885     foreach($rs as $cat) {
 886         context_instance_preload($cat);
 887         $catcontext = get_context_instance(CONTEXT_COURSECAT, $cat->id);
 888         if ($cat->visible || has_capability('moodle/category:viewhiddencategories', $catcontext)) {
 889             $categories[$cat->id] = $cat;
 890         }
 891     }
 892     $rs->close();
 893     return $categories;
 894 }
 895
 896
 897 /**
 898  * Returns an array of category ids of all the subcategories for a given
 899  * category.
 900  *
 901  * @global object
 902  * @param int $catid - The id of the category whose subcategories we want to find.
 903  * @return array of category ids.
 904  */
 905 function get_all_subcategories($catid) {
 906     global $DB;
 907
 908     $subcats = array();
 909
 910     if ($categories = $DB->get_records('course_categories', array('parent'=>$catid))) {
 911         foreach ($categories as $cat) {
 912             array_push($subcats, $cat->id);
 913             $subcats = array_merge($subcats, get_all_subcategories($cat->id));
 914         }
 915     }
 916     return $subcats;
 917 }
 918
 919 /**
 920  * Return specified category, default if given does not exist
 921  *
 922  * @global object
 923  * @uses MAX_COURSES_IN_CATEGORY
 924  * @uses CONTEXT_COURSECAT
 925  * @uses SYSCONTEXTID
 926  * @param int $catid course category id
 927  * @return object caregory
 928  */
 929 function get_course_category($catid=0) {
 930     global $DB;
 931
 932     $category = false;
 933
 934     if (!empty($catid)) {
 935         $category = $DB->get_record('course_categories', array('id'=>$catid));
 936     }
 937
 938     if (!$category) {
 939         // the first category is considered default for now
 940         if ($category = $DB->get_records('course_categories', null, 'sortorder', '*', 0, 1)) {
 941             $category = reset($category);
 942
 943         } else {
 944             $cat = new stdClass();
 945             $cat->name         = get_string('miscellaneous');
 946             $cat->depth        = 1;
 947             $cat->sortorder    = MAX_COURSES_IN_CATEGORY;
 948             $cat->timemodified = time();
 949             $catid = $DB->insert_record('course_categories', $cat);
 950             // make sure category context exists
 951             get_context_instance(CONTEXT_COURSECAT, $catid);
 952             mark_context_dirty('/'.SYSCONTEXTID);
 953             fix_course_sortorder(); // Required to build course_categories.depth and .path.
 954             $category = $DB->get_record('course_categories', array('id'=>$catid));
 955         }
 956     }
 957
 958     return $category;
 959 }
 960
 961 /**
 962  * Fixes course category and course sortorder, also verifies category and course parents and paths.
 963  * (circular references are not fixed)
 964  *
 965  * @global object
 966  * @global object
 967  * @uses MAX_COURSES_IN_CATEGORY
 968  * @uses MAX_COURSE_CATEGORIES
 969  * @uses SITEID
 970  * @uses CONTEXT_COURSE
 971  * @return void
 972  */
 973 function fix_course_sortorder() {
 974     global $DB, $SITE;
 975
 976     //WARNING: this is PHP5 only code!
 977
 978     if ($unsorted = $DB->get_records('course_categories', array('sortorder'=>0))) {
 979         //move all categories that are not sorted yet to the end
 980         $DB->set_field('course_categories', 'sortorder', MAX_COURSES_IN_CATEGORY*MAX_COURSE_CATEGORIES, array('sortorder'=>0));
 981     }
 982
 983     $allcats = $DB->get_records('course_categories', null, 'sortorder, id', 'id, sortorder, parent, depth, path');
 984     $topcats    = array();
 985     $brokencats = array();
 986     foreach ($allcats as $cat) {
 987         $sortorder = (int)$cat->sortorder;
 988         if (!$cat->parent) {
 989             while(isset($topcats[$sortorder])) {
 990                 $sortorder++;
 991             }
 992             $topcats[$sortorder] = $cat;
 993             continue;
 994         }
 995         if (!isset($allcats[$cat->parent])) {
 996             $brokencats[] = $cat;
 997             continue;
 998         }
 999         if (!isset($allcats[$cat->parent]->children)) {
1000             $allcats[$cat->parent]->children = array();
1001         }
1002         while(isset($allcats[$cat->parent]->children[$sortorder])) {
1003             $sortorder++;
1004         }
1005         $allcats[$cat->parent]->children[$sortorder] = $cat;
1006     }
1007     unset($allcats);
1008
1009     // add broken cats to category tree
1010     if ($brokencats) {
1011         $defaultcat = reset($topcats);
1012         foreach ($brokencats as $cat) {
1013             $topcats[] = $cat;
1014         }
1015     }
1016
1017     // now walk recursively the tree and fix any problems found
1018     $sortorder = 0;
1019     $fixcontexts = array();
1020     _fix_course_cats($topcats, $sortorder, 0, 0, '', $fixcontexts);
1021
1022     // detect if there are "multiple" frontpage courses and fix them if needed
1023     $frontcourses = $DB->get_records('course', array('category'=>0), 'id');
1024     if (count($frontcourses) > 1) {
1025         if (isset($frontcourses[SITEID])) {
1026             $frontcourse = $frontcourses[SITEID];
1027             unset($frontcourses[SITEID]);
1028         } else {
1029             $frontcourse = array_shift($frontcourses);
1030         }
1031         $defaultcat = reset($topcats);
1032         foreach ($frontcourses as $course) {
1033             $DB->set_field('course', 'category', $defaultcat->id, array('id'=>$course->id));
1034             $context = get_context_instance(CONTEXT_COURSE, $course->id);
1035             $fixcontexts[$context->id] = $context;
1036         }
1037         unset($frontcourses);
1038     } else {
1039         $frontcourse = reset($frontcourses);
1040     }
1041
1042     // now fix the paths and depths in context table if needed
1043     if ($fixcontexts) {
1044         foreach ($fixcontexts as $fixcontext) {
1045             $fixcontext->reset_paths(false);
1046         }
1047         context_helper::build_all_paths(false);
1048         unset($fixcontexts);
1049     }
1050
1051     // release memory
1052     unset($topcats);
1053     unset($brokencats);
1054     unset($fixcontexts);
1055
1056     // fix frontpage course sortorder
1057     if ($frontcourse->sortorder != 1) {
1058         $DB->set_field('course', 'sortorder', 1, array('id'=>$frontcourse->id));
1059     }
1060
1061     // now fix the course counts in category records if needed
1062     $sql = "SELECT cc.id, cc.coursecount, COUNT(c.id) AS newcount
1063               FROM {course_categories} cc
1064               LEFT JOIN {course} c ON c.category = cc.id
1065           GROUP BY cc.id, cc.coursecount
1066             HAVING cc.coursecount <> COUNT(c.id)";
1067
1068     if ($updatecounts = $DB->get_records_sql($sql)) {
1069         // categories with more courses than MAX_COURSES_IN_CATEGORY
1070         $categories = array();
1071         foreach ($updatecounts as $cat) {
1072             $cat->coursecount = $cat->newcount;
1073             if ($cat->coursecount >= MAX_COURSES_IN_CATEGORY) {
1074                 $categories[] = $cat->id;
1075             }
1076             unset($cat->newcount);
1077             $DB->update_record_raw('course_categories', $cat, true);
1078         }
1079         if (!empty($categories)) {
1080             $str = implode(', ', $categories);
1081             debugging("The number of courses (category id: $str) has reached MAX_COURSES_IN_CATEGORY (" . MAX_COURSES_IN_CATEGORY . "), it will cause a sorting performance issue, please increase the value of MAX_COURSES_IN_CATEGORY in lib/datalib.php file. See tracker issue: MDL-25669", DEBUG_DEVELOPER);
1082         }
1083     }
1084
1085     // now make sure that sortorders in course table are withing the category sortorder ranges
1086     $sql = "SELECT DISTINCT cc.id, cc.sortorder
1087               FROM {course_categories} cc
1088               JOIN {course} c ON c.category = cc.id
1089              WHERE c.sortorder < cc.sortorder OR c.sortorder > cc.sortorder + ".MAX_COURSES_IN_CATEGORY;
1090
1091     if ($fixcategories = $DB->get_records_sql($sql)) {
1092         //fix the course sortorder ranges
1093         foreach ($fixcategories as $cat) {
1094             $sql = "UPDATE {course}
1095                        SET sortorder = ".$DB->sql_modulo('sortorder', MAX_COURSES_IN_CATEGORY)." + ?
1096                      WHERE category = ?";
1097             $DB->execute($sql, array($cat->sortorder, $cat->id));
1098         }
1099     }
1100     unset($fixcategories);
1101
1102     // categories having courses with sortorder duplicates or having gaps in sortorder
1103     $sql = "SELECT DISTINCT c1.category AS id , cc.sortorder
1104               FROM {course} c1
1105               JOIN {course} c2 ON c1.sortorder = c2.sortorder
1106               JOIN {course_categories} cc ON (c1.category = cc.id)
1107              WHERE c1.id <> c2.id";
1108     $fixcategories = $DB->get_records_sql($sql);
1109
1110     $sql = "SELECT cc.id, cc.sortorder, cc.coursecount, MAX(c.sortorder) AS maxsort, MIN(c.sortorder) AS minsort
1111               FROM {course_categories} cc
1112               JOIN {course} c ON c.category = cc.id
1113           GROUP BY cc.id, cc.sortorder, cc.coursecount
1114             HAVING (MAX(c.sortorder) <>  cc.sortorder + cc.coursecount) OR (MIN(c.sortorder) <>  cc.sortorder + 1)";
1115     $gapcategories = $DB->get_records_sql($sql);
1116
1117     foreach ($gapcategories as $cat) {
1118         if (isset($fixcategories[$cat->id])) {
1119             // duplicates detected already
1120
1121         } else if ($cat->minsort == $cat->sortorder and $cat->maxsort == $cat->sortorder + $cat->coursecount - 1) {
1122             // easy - new course inserted with sortorder 0, the rest is ok
1123             $sql = "UPDATE {course}
1124                        SET sortorder = sortorder + 1
1125                      WHERE category = ?";
1126             $DB->execute($sql, array($cat->id));
1127
1128         } else {
1129             // it needs full resorting
1130             $fixcategories[$cat->id] = $cat;
1131         }
1132     }
1133     unset($gapcategories);
1134
1135     // fix course sortorders in problematic categories only
1136     foreach ($fixcategories as $cat) {
1137         $i = 1;
1138         $courses = $DB->get_records('course', array('category'=>$cat->id), 'sortorder ASC, id DESC', 'id, sortorder');
1139         foreach ($courses as $course) {
1140             if ($course->sortorder != $cat->sortorder + $i) {
1141                 $course->sortorder = $cat->sortorder + $i;
1142                 $DB->update_record_raw('course', $course, true);
1143             }
1144             $i++;
1145         }
1146     }
1147 }
1148
1149 /**
1150  * Internal recursive category verification function, do not use directly!
1151  *
1152  * @todo Document the arguments of this function better
1153  *
1154  * @global object
1155  * @uses MAX_COURSES_IN_CATEGORY
1156  * @uses CONTEXT_COURSECAT
1157  * @param array $children
1158  * @param int $sortorder
1159  * @param string $parent
1160  * @param int $depth
1161  * @param string $path
1162  * @param array $fixcontexts
1163  * @return void
1164  */
1165 function _fix_course_cats($children, &$sortorder, $parent, $depth, $path, &$fixcontexts) {
1166     global $DB;
1167
1168     $depth++;
1169
1170     foreach ($children as $cat) {
1171         $sortorder = $sortorder + MAX_COURSES_IN_CATEGORY;
1172         $update = false;
1173         if ($parent != $cat->parent or $depth != $cat->depth or $path.'/'.$cat->id != $cat->path) {
1174             $cat->parent = $parent;
1175             $cat->depth  = $depth;
1176             $cat->path   = $path.'/'.$cat->id;
1177             $update = true;
1178
1179             // make sure context caches are rebuild and dirty contexts marked
1180             $context = get_context_instance(CONTEXT_COURSECAT, $cat->id);
1181             $fixcontexts[$context->id] = $context;
1182         }
1183         if ($cat->sortorder != $sortorder) {
1184             $cat->sortorder = $sortorder;
1185             $update = true;
1186         }
1187         if ($update) {
1188             $DB->update_record('course_categories', $cat, true);
1189         }
1190         if (isset($cat->children)) {
1191             _fix_course_cats($cat->children, $sortorder, $cat->id, $cat->depth, $cat->path, $fixcontexts);
1192         }
1193     }
1194 }
1195
1196 /**
1197  * List of remote courses that a user has access to via MNET.
1198  * Works only on the IDP
1199  *
1200  * @global object
1201  * @global object
1202  * @param int @userid The user id to get remote courses for
1203  * @return array Array of {@link $COURSE} of course objects
1204  */
1205 function get_my_remotecourses($userid=0) {
1206     global $DB, $USER;
1207
1208     if (empty($userid)) {
1209         $userid = $USER->id;
1210     }
1211
1212     // we can not use SELECT DISTINCT + text field (summary) because of MS SQL and Oracle, subselect used therefore
1213     $sql = "SELECT c.id, c.remoteid, c.shortname, c.fullname,
1214                    c.hostid, c.summary, c.summaryformat, c.categoryname AS cat_name,
1215                    h.name AS hostname
1216               FROM {mnetservice_enrol_courses} c
1217               JOIN (SELECT DISTINCT hostid, remotecourseid
1218                       FROM {mnetservice_enrol_enrolments}
1219                      WHERE userid = ?
1220                    ) e ON (e.hostid = c.hostid AND e.remotecourseid = c.remoteid)
1221               JOIN {mnet_host} h ON h.id = c.hostid";
1222
1223     return $DB->get_records_sql($sql, array($userid));
1224 }
1225
1226 /**
1227  * List of remote hosts that a user has access to via MNET.
1228  * Works on the SP
1229  *
1230  * @global object
1231  * @global object
1232  * @return array|bool Array of host objects or false
1233  */
1234 function get_my_remotehosts() {
1235     global $CFG, $USER;
1236
1237     if ($USER->mnethostid == $CFG->mnet_localhost_id) {
1238         return false; // Return nothing on the IDP
1239     }
1240     if (!empty($USER->mnet_foreign_host_array) && is_array($USER->mnet_foreign_host_array)) {
1241         return $USER->mnet_foreign_host_array;
1242     }
1243     return false;
1244 }
1245
1246 /**
1247  * This function creates a default separated/connected scale
1248  *
1249  * This function creates a default separated/connected scale
1250  * so there's something in the database.  The locations of
1251  * strings and files is a bit odd, but this is because we
1252  * need to maintain backward compatibility with many different
1253  * existing language translations and older sites.
1254  *
1255  * @global object
1256  * @return void
1257  */
1258 function make_default_scale() {
1259     global $DB;
1260
1261     $defaultscale = new stdClass();
1262     $defaultscale->courseid = 0;
1263     $defaultscale->userid = 0;
1264     $defaultscale->name  = get_string('separateandconnected');
1265     $defaultscale->description = get_string('separateandconnectedinfo');
1266     $defaultscale->scale = get_string('postrating1', 'forum').','.
1267                            get_string('postrating2', 'forum').','.
1268                            get_string('postrating3', 'forum');
1269     $defaultscale->timemodified = time();
1270
1271     $defaultscale->id = $DB->insert_record('scale', $defaultscale);
1272     $DB->execute("UPDATE {forum} SET scale = ?", array($defaultscale->id));
1273 }
1274
1275
1276 /**
1277  * Returns a menu of all available scales from the site as well as the given course
1278  *
1279  * @global object
1280  * @param int $courseid The id of the course as found in the 'course' table.
1281  * @return array
1282  */
1283 function get_scales_menu($courseid=0) {
1284     global $DB;
1285
1286     $sql = "SELECT id, name
1287               FROM {scale}
1288              WHERE courseid = 0 or courseid = ?
1289           ORDER BY courseid ASC, name ASC";
1290     $params = array($courseid);
1291
1292     if ($scales = $DB->get_records_sql_menu($sql, $params)) {
1293         return $scales;
1294     }
1295
1296     make_default_scale();
1297
1298     return $DB->get_records_sql_menu($sql, $params);
1299 }
1300
1301
1302
1303 /**
1304  * Given a set of timezone records, put them in the database,  replacing what is there
1305  *
1306  * @global object
1307  * @param array $timezones An array of timezone records
1308  * @return void
1309  */
1310 function update_timezone_records($timezones) {
1311     global $DB;
1312
1313 /// Clear out all the old stuff
1314     $DB->delete_records('timezone');
1315
1316 /// Insert all the new stuff
1317     foreach ($timezones as $timezone) {
1318         if (is_array($timezone)) {
1319             $timezone = (object)$timezone;
1320         }
1321         $DB->insert_record('timezone', $timezone);
1322     }
1323 }
1324
1325
1326 /// MODULE FUNCTIONS /////////////////////////////////////////////////
1327
1328 /**
1329  * Just gets a raw list of all modules in a course
1330  *
1331  * @global object
1332  * @param int $courseid The id of the course as found in the 'course' table.
1333  * @return array
1334  */
1335 function get_course_mods($courseid) {
1336     global $DB;
1337
1338     if (empty($courseid)) {
1339         return false; // avoid warnings
1340     }
1341
1342     return $DB->get_records_sql("SELECT cm.*, m.name as modname
1343                                    FROM {modules} m, {course_modules} cm
1344                                   WHERE cm.course = ? AND cm.module = m.id AND m.visible = 1",
1345                                 array($courseid)); // no disabled mods
1346 }
1347
1348
1349 /**
1350  * Given an id of a course module, finds the coursemodule description
1351  *
1352  * @global object
1353  * @param string $modulename name of module type, eg. resource, assignment,... (optional, slower and less safe if not specified)
1354  * @param int $cmid course module id (id in course_modules table)
1355  * @param int $courseid optional course id for extra validation
1356  * @param bool $sectionnum include relative section number (0,1,2 ...)
1357  * @param int $strictness IGNORE_MISSING means compatible mode, false returned if record not found, debug message if more found;
1358  *                        IGNORE_MULTIPLE means return first, ignore multiple records found(not recommended);
1359  *                        MUST_EXIST means throw exception if no record or multiple records found
1360  * @return stdClass
1361  */
1362 function get_coursemodule_from_id($modulename, $cmid, $courseid=0, $sectionnum=false, $strictness=IGNORE_MISSING) {
1363     global $DB;
1364
1365     $params = array('cmid'=>$cmid);
1366
1367     if (!$modulename) {
1368         if (!$modulename = $DB->get_field_sql("SELECT md.name
1369                                                  FROM {modules} md
1370                                                  JOIN {course_modules} cm ON cm.module = md.id
1371                                                 WHERE cm.id = :cmid", $params, $strictness)) {
1372             return false;
1373         }
1374     }
1375
1376     $params['modulename'] = $modulename;
1377
1378     $courseselect = "";
1379     $sectionfield = "";
1380     $sectionjoin  = "";
1381
1382     if ($courseid) {
1383         $courseselect = "AND cm.course = :courseid";
1384         $params['courseid'] = $courseid;
1385     }
1386
1387     if ($sectionnum) {
1388         $sectionfield = ", cw.section AS sectionnum";
1389         $sectionjoin  = "LEFT JOIN {course_sections} cw ON cw.id = cm.section";
1390     }
1391
1392     $sql = "SELECT cm.*, m.name, md.name AS modname $sectionfield
1393               FROM {course_modules} cm
1394                    JOIN {modules} md ON md.id = cm.module
1395                    JOIN {".$modulename."} m ON m.id = cm.instance
1396                    $sectionjoin
1397              WHERE cm.id = :cmid AND md.name = :modulename
1398                    $courseselect";
1399
1400     return $DB->get_record_sql($sql, $params, $strictness);
1401 }
1402
1403 /**
1404  * Given an instance number of a module, finds the coursemodule description
1405  *
1406  * @global object
1407  * @param string $modulename name of module type, eg. resource, assignment,...
1408  * @param int $instance module instance number (id in resource, assignment etc. table)
1409  * @param int $courseid optional course id for extra validation
1410  * @param bool $sectionnum include relative section number (0,1,2 ...)
1411  * @param int $strictness IGNORE_MISSING means compatible mode, false returned if record not found, debug message if more found;
1412  *                        IGNORE_MULTIPLE means return first, ignore multiple records found(not recommended);
1413  *                        MUST_EXIST means throw exception if no record or multiple records found
1414  * @return stdClass
1415  */
1416 function get_coursemodule_from_instance($modulename, $instance, $courseid=0, $sectionnum=false, $strictness=IGNORE_MISSING) {
1417     global $DB;
1418
1419     $params = array('instance'=>$instance, 'modulename'=>$modulename);
1420
1421     $courseselect = "";
1422     $sectionfield = "";
1423     $sectionjoin  = "";
1424
1425     if ($courseid) {
1426         $courseselect = "AND cm.course = :courseid";
1427         $params['courseid'] = $courseid;
1428     }
1429
1430     if ($sectionnum) {
1431         $sectionfield = ", cw.section AS sectionnum";
1432         $sectionjoin  = "LEFT JOIN {course_sections} cw ON cw.id = cm.section";
1433     }
1434
1435     $sql = "SELECT cm.*, m.name, md.name AS modname $sectionfield
1436               FROM {course_modules} cm
1437                    JOIN {modules} md ON md.id = cm.module
1438                    JOIN {".$modulename."} m ON m.id = cm.instance
1439                    $sectionjoin
1440              WHERE m.id = :instance AND md.name = :modulename
1441                    $courseselect";
1442
1443     return $DB->get_record_sql($sql, $params, $strictness);
1444 }
1445
1446 /**
1447  * Returns all course modules of given activity in course
1448  *
1449  * @param string $modulename The module name (forum, quiz, etc.)
1450  * @param int $courseid The course id to get modules for
1451  * @param string $extrafields extra fields starting with m.
1452  * @return array Array of results
1453  */
1454 function get_coursemodules_in_course($modulename, $courseid, $extrafields='') {
1455     global $DB;
1456
1457     if (!empty($extrafields)) {
1458         $extrafields = ", $extrafields";
1459     }
1460     $params = array();
1461     $params['courseid'] = $courseid;
1462     $params['modulename'] = $modulename;
1463
1464
1465     return $DB->get_records_sql("SELECT cm.*, m.name, md.name as modname $extrafields
1466                                    FROM {course_modules} cm, {modules} md, {".$modulename."} m
1467                                   WHERE cm.course = :courseid AND
1468                                         cm.instance = m.id AND
1469                                         md.name = :modulename AND
1470                                         md.id = cm.module", $params);
1471 }
1472
1473 /**
1474  * Returns an array of all the active instances of a particular module in given courses, sorted in the order they are defined
1475  *
1476  * Returns an array of all the active instances of a particular
1477  * module in given courses, sorted in the order they are defined
1478  * in the course. Returns an empty array on any errors.
1479  *
1480  * The returned objects includle the columns cw.section, cm.visible,
1481  * cm.groupmode and cm.groupingid, cm.groupmembersonly, and are indexed by cm.id.
1482  *
1483  * @global object
1484  * @global object
1485  * @param string $modulename The name of the module to get instances for
1486  * @param array $courses an array of course objects.
1487  * @param int $userid
1488  * @param int $includeinvisible
1489  * @return array of module instance objects, including some extra fields from the course_modules
1490  *          and course_sections tables, or an empty array if an error occurred.
1491  */
1492 function get_all_instances_in_courses($modulename, $courses, $userid=NULL, $includeinvisible=false) {
1493     global $CFG, $DB;
1494
1495     $outputarray = array();
1496
1497     if (empty($courses) || !is_array($courses) || count($courses) == 0) {
1498         return $outputarray;
1499     }
1500
1501     list($coursessql, $params) = $DB->get_in_or_equal(array_keys($courses), SQL_PARAMS_NAMED, 'c0');
1502     $params['modulename'] = $modulename;
1503
1504     if (!$rawmods = $DB->get_records_sql("SELECT cm.id AS coursemodule, m.*, cw.section, cm.visible AS visible,
1505                                                  cm.groupmode, cm.groupingid, cm.groupmembersonly
1506                                             FROM {course_modules} cm, {course_sections} cw, {modules} md,
1507                                                  {".$modulename."} m
1508                                            WHERE cm.course $coursessql AND
1509                                                  cm.instance = m.id AND
1510                                                  cm.section = cw.id AND
1511                                                  md.name = :modulename AND
1512                                                  md.id = cm.module", $params)) {
1513         return $outputarray;
1514     }
1515
1516     foreach ($courses as $course) {
1517         $modinfo = get_fast_modinfo($course, $userid);
1518
1519         if (empty($modinfo->instances[$modulename])) {
1520             continue;
1521         }
1522
1523         foreach ($modinfo->instances[$modulename] as $cm) {
1524             if (!$includeinvisible and !$cm->uservisible) {
1525                 continue;
1526             }
1527             if (!isset($rawmods[$cm->id])) {
1528                 continue;
1529             }
1530             $instance = $rawmods[$cm->id];
1531             if (!empty($cm->extra)) {
1532                 $instance->extra = $cm->extra;
1533             }
1534             $outputarray[] = $instance;
1535         }
1536     }
1537
1538     return $outputarray;
1539 }
1540
1541 /**
1542  * Returns an array of all the active instances of a particular module in a given course,
1543  * sorted in the order they are defined.
1544  *
1545  * Returns an array of all the active instances of a particular
1546  * module in a given course, sorted in the order they are defined
1547  * in the course. Returns an empty array on any errors.
1548  *
1549  * The returned objects includle the columns cw.section, cm.visible,
1550  * cm.groupmode and cm.groupingid, cm.groupmembersonly, and are indexed by cm.id.
1551  *
1552  * Simply calls {@link all_instances_in_courses()} with a single provided course
1553  *
1554  * @param string $modulename The name of the module to get instances for
1555  * @param object $course The course obect.
1556  * @return array of module instance objects, including some extra fields from the course_modules
1557  *          and course_sections tables, or an empty array if an error occurred.
1558  * @param int $userid
1559  * @param int $includeinvisible
1560  */
1561 function get_all_instances_in_course($modulename, $course, $userid=NULL, $includeinvisible=false) {
1562     return get_all_instances_in_courses($modulename, array($course->id => $course), $userid, $includeinvisible);
1563 }
1564
1565
1566 /**
1567  * Determine whether a module instance is visible within a course
1568  *
1569  * Given a valid module object with info about the id and course,
1570  * and the module's type (eg "forum") returns whether the object
1571  * is visible or not, groupmembersonly visibility not tested
1572  *
1573  * @global object
1574
1575  * @param $moduletype Name of the module eg 'forum'
1576  * @param $module Object which is the instance of the module
1577  * @return bool Success
1578  */
1579 function instance_is_visible($moduletype, $module) {
1580     global $DB;
1581
1582     if (!empty($module->id)) {
1583         $params = array('courseid'=>$module->course, 'moduletype'=>$moduletype, 'moduleid'=>$module->id);
1584         if ($records = $DB->get_records_sql("SELECT cm.instance, cm.visible, cm.groupingid, cm.id, cm.groupmembersonly, cm.course
1585                                                FROM {course_modules} cm, {modules} m
1586                                               WHERE cm.course = :courseid AND
1587                                                     cm.module = m.id AND
1588                                                     m.name = :moduletype AND
1589                                                     cm.instance = :moduleid", $params)) {
1590
1591             foreach ($records as $record) { // there should only be one - use the first one
1592                 return $record->visible;
1593             }
1594         }
1595     }
1596     return true;  // visible by default!
1597 }
1598
1599 /**
1600  * Determine whether a course module is visible within a course,
1601  * this is different from instance_is_visible() - faster and visibility for user
1602  *
1603  * @global object
1604  * @global object
1605  * @uses DEBUG_DEVELOPER
1606  * @uses CONTEXT_MODULE
1607  * @uses CONDITION_MISSING_EXTRATABLE
1608  * @param object $cm object
1609  * @param int $userid empty means current user
1610  * @return bool Success
1611  */
1612 function coursemodule_visible_for_user($cm, $userid=0) {
1613     global $USER,$CFG;
1614
1615     if (empty($cm->id)) {
1616         debugging("Incorrect course module parameter!", DEBUG_DEVELOPER);
1617         return false;
1618     }
1619     if (empty($userid)) {
1620         $userid = $USER->id;
1621     }
1622     if (!$cm->visible and !has_capability('moodle/course:viewhiddenactivities', get_context_instance(CONTEXT_MODULE, $cm->id), $userid)) {
1623         return false;
1624     }
1625     if ($CFG->enableavailability) {
1626         require_once($CFG->libdir.'/conditionlib.php');
1627         $ci=new condition_info($cm,CONDITION_MISSING_EXTRATABLE);
1628         if(!$ci->is_available($cm->availableinfo,false,$userid) and
1629             !has_capability('moodle/course:viewhiddenactivities',
1630                 get_context_instance(CONTEXT_MODULE, $cm->id), $userid)) {
1631             return false;
1632         }
1633     }
1634     return groups_course_module_visible($cm, $userid);
1635 }
1636
1637
1638
1639
1640 /// LOG FUNCTIONS /////////////////////////////////////////////////////
1641
1642
1643 /**
1644  * Add an entry to the log table.
1645  *
1646  * Add an entry to the log table.  These are "action" focussed rather
1647  * than web server hits, and provide a way to easily reconstruct what
1648  * any particular student has been doing.
1649  *
1650  * @package core
1651  * @category log
1652  * @global moodle_database $DB
1653  * @global stdClass $CFG
1654  * @global stdClass $USER
1655  * @uses SITEID
1656  * @uses DEBUG_DEVELOPER
1657  * @uses DEBUG_ALL
1658  * @param    int     $courseid  The course id
1659  * @param    string  $module  The module name  e.g. forum, journal, resource, course, user etc
1660  * @param    string  $action  'view', 'update', 'add' or 'delete', possibly followed by another word to clarify.
1661  * @param    string  $url     The file and parameters used to see the results of the action
1662  * @param    string  $info    Additional description information
1663  * @param    string  $cm      The course_module->id if there is one
1664  * @param    string  $user    If log regards $user other than $USER
1665  * @return void
1666  */
1667 function add_to_log($courseid, $module, $action, $url='', $info='', $cm=0, $user=0) {
1668     // Note that this function intentionally does not follow the normal Moodle DB access idioms.
1669     // This is for a good reason: it is the most frequently used DB update function,
1670     // so it has been optimised for speed.
1671     global $DB, $CFG, $USER;
1672
1673     if ($cm === '' || is_null($cm)) { // postgres won't translate empty string to its default
1674         $cm = 0;
1675     }
1676
1677     if ($user) {
1678         $userid = $user;
1679     } else {
1680         if (session_is_loggedinas()) {  // Don't log
1681             return;
1682         }
1683         $userid = empty($USER->id) ? '0' : $USER->id;
1684     }
1685
1686     if (isset($CFG->logguests) and !$CFG->logguests) {
1687         if (!$userid or isguestuser($userid)) {
1688             return;
1689         }
1690     }
1691
1692     $REMOTE_ADDR = getremoteaddr();
1693
1694     $timenow = time();
1695     $info = $info;
1696     if (!empty($url)) { // could break doing html_entity_decode on an empty var.
1697         $url = html_entity_decode($url);
1698     } else {
1699         $url = '';
1700     }
1701
1702     // Restrict length of log lines to the space actually available in the
1703     // database so that it doesn't cause a DB error. Log a warning so that
1704     // developers can avoid doing things which are likely to cause this on a
1705     // routine basis.
1706     if(!empty($info) && textlib::strlen($info)>255) {
1707         $info = textlib::substr($info,0,252).'...';
1708         debugging('Warning: logged very long info',DEBUG_DEVELOPER);
1709     }
1710
1711     // If the 100 field size is changed, also need to alter print_log in course/lib.php
1712     if(!empty($url) && textlib::strlen($url)>100) {
1713         $url = textlib::substr($url,0,97).'...';
1714         debugging('Warning: logged very long URL',DEBUG_DEVELOPER);
1715     }
1716
1717     if (defined('MDL_PERFDB')) { global $PERF ; $PERF->logwrites++;};
1718
1719     $log = array('time'=>$timenow, 'userid'=>$userid, 'course'=>$courseid, 'ip'=>$REMOTE_ADDR, 'module'=>$module,
1720                  'cmid'=>$cm, 'action'=>$action, 'url'=>$url, 'info'=>$info);
1721
1722     try {
1723         $DB->insert_record_raw('log', $log, false);
1724     } catch (dml_exception $e) {
1725         debugging('Error: Could not insert a new entry to the Moodle log. '. $e->error, DEBUG_ALL);
1726
1727         // MDL-11893, alert $CFG->supportemail if insert into log failed
1728         if ($CFG->supportemail and empty($CFG->noemailever)) {
1729             // email_to_user is not usable because email_to_user tries to write to the logs table,
1730             // and this will get caught in an infinite loop, if disk is full
1731             $site = get_site();
1732             $subject = 'Insert into log failed at your moodle site '.$site->fullname;
1733             $message = "Insert into log table failed at ". date('l dS \of F Y h:i:s A') .".\n It is possible that your disk is full.\n\n";
1734             $message .= "The failed query parameters are:\n\n" . var_export($log, true);
1735
1736             $lasttime = get_config('admin', 'lastloginserterrormail');
1737             if(empty($lasttime) || time() - $lasttime > 60*60*24) { // limit to 1 email per day
1738                 //using email directly rather than messaging as they may not be able to log in to access a message
1739                 mail($CFG->supportemail, $subject, $message);
1740                 set_config('lastloginserterrormail', time(), 'admin');
1741             }
1742         }
1743     }
1744 }
1745
1746 /**
1747  * Store user last access times - called when use enters a course or site
1748  *
1749  * @package core
1750  * @category log
1751  * @global stdClass $USER
1752  * @global stdClass $CFG
1753  * @global moodle_database $DB
1754  * @uses LASTACCESS_UPDATE_SECS
1755  * @uses SITEID
1756  * @param int $courseid  empty courseid means site
1757  * @return void
1758  */
1759 function user_accesstime_log($courseid=0) {
1760     global $USER, $CFG, $DB;
1761
1762     if (!isloggedin() or session_is_loggedinas()) {
1763         // no access tracking
1764         return;
1765     }
1766
1767     if (empty($courseid)) {
1768         $courseid = SITEID;
1769     }
1770
1771     $timenow = time();
1772
1773 /// Store site lastaccess time for the current user
1774     if ($timenow - $USER->lastaccess > LASTACCESS_UPDATE_SECS) {
1775     /// Update $USER->lastaccess for next checks
1776         $USER->lastaccess = $timenow;
1777
1778         $last = new stdClass();
1779         $last->id         = $USER->id;
1780         $last->lastip     = getremoteaddr();
1781         $last->lastaccess = $timenow;
1782
1783         $DB->update_record_raw('user', $last);
1784     }
1785
1786     if ($courseid == SITEID) {
1787     ///  no user_lastaccess for frontpage
1788         return;
1789     }
1790
1791 /// Store course lastaccess times for the current user
1792     if (empty($USER->currentcourseaccess[$courseid]) or ($timenow - $USER->currentcourseaccess[$courseid] > LASTACCESS_UPDATE_SECS)) {
1793
1794         $lastaccess = $DB->get_field('user_lastaccess', 'timeaccess', array('userid'=>$USER->id, 'courseid'=>$courseid));
1795
1796         if ($lastaccess === false) {
1797             // Update course lastaccess for next checks
1798             $USER->currentcourseaccess[$courseid] = $timenow;
1799
1800             $last = new stdClass();
1801             $last->userid     = $USER->id;
1802             $last->courseid   = $courseid;
1803             $last->timeaccess = $timenow;
1804             $DB->insert_record_raw('user_lastaccess', $last, false);
1805
1806         } else if ($timenow - $lastaccess <  LASTACCESS_UPDATE_SECS) {
1807             // no need to update now, it was updated recently in concurrent login ;-)
1808
1809         } else {
1810             // Update course lastaccess for next checks
1811             $USER->currentcourseaccess[$courseid] = $timenow;
1812
1813             $DB->set_field('user_lastaccess', 'timeaccess', $timenow, array('userid'=>$USER->id, 'courseid'=>$courseid));
1814         }
1815     }
1816 }
1817
1818 /**
1819  * Select all log records based on SQL criteria
1820  *
1821  * @package core
1822  * @category log
1823  * @global moodle_database $DB
1824  * @param string $select SQL select criteria
1825  * @param array $params named sql type params
1826  * @param string $order SQL order by clause to sort the records returned
1827  * @param string $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set)
1828  * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set)
1829  * @param int $totalcount Passed in by reference.
1830  * @return array
1831  */
1832 function get_logs($select, array $params=null, $order='l.time DESC', $limitfrom='', $limitnum='', &$totalcount) {
1833     global $DB;
1834
1835     if ($order) {
1836         $order = "ORDER BY $order";
1837     }
1838
1839     $selectsql = "";
1840     $countsql  = "";
1841
1842     if ($select) {
1843         $select = "WHERE $select";
1844     }
1845
1846     $sql = "SELECT COUNT(*)
1847               FROM {log} l
1848            $select";
1849
1850     $totalcount = $DB->count_records_sql($sql, $params);
1851
1852     $sql = "SELECT l.*, u.firstname, u.lastname, u.picture
1853               FROM {log} l
1854               LEFT JOIN {user} u ON l.userid = u.id
1855            $select
1856             $order";
1857
1858     return $DB->get_records_sql($sql, $params, $limitfrom, $limitnum) ;
1859 }
1860
1861
1862 /**
1863  * Select all log records for a given course and user
1864  *
1865  * @package core
1866  * @category log
1867  * @global moodle_database $DB
1868  * @uses DAYSECS
1869  * @param int $userid The id of the user as found in the 'user' table.
1870  * @param int $courseid The id of the course as found in the 'course' table.
1871  * @param string $coursestart unix timestamp representing course start date and time.
1872  * @return array
1873  */
1874 function get_logs_usercourse($userid, $courseid, $coursestart) {
1875     global $DB;
1876
1877     $params = array();
1878
1879     $courseselect = '';
1880     if ($courseid) {
1881         $courseselect = "AND course = :courseid";
1882         $params['courseid'] = $courseid;
1883     }
1884     $params['userid'] = $userid;
1885     $$coursestart = (int)$coursestart; // note: unfortunately pg complains if you use name parameter or column alias in GROUP BY
1886
1887     return $DB->get_records_sql("SELECT FLOOR((time - $coursestart)/". DAYSECS .") AS day, COUNT(*) AS num
1888                                    FROM {log}
1889                                   WHERE userid = :userid
1890                                         AND time > $coursestart $courseselect
1891                                GROUP BY FLOOR((time - $coursestart)/". DAYSECS .")", $params);
1892 }
1893
1894 /**
1895  * Select all log records for a given course, user, and day
1896  *
1897  * @package core
1898  * @category log
1899  * @global moodle_database $DB
1900  * @uses HOURSECS
1901  * @param int $userid The id of the user as found in the 'user' table.
1902  * @param int $courseid The id of the course as found in the 'course' table.
1903  * @param string $daystart unix timestamp of the start of the day for which the logs needs to be retrived
1904  * @return array
1905  */
1906 function get_logs_userday($userid, $courseid, $daystart) {
1907     global $DB;
1908
1909     $params = array('userid'=>$userid);
1910
1911     $courseselect = '';
1912     if ($courseid) {
1913         $courseselect = "AND course = :courseid";
1914         $params['courseid'] = $courseid;
1915     }
1916     $daystart = (int)$daystart; // note: unfortunately pg complains if you use name parameter or column alias in GROUP BY
1917
1918     return $DB->get_records_sql("SELECT FLOOR((time - $daystart)/". HOURSECS .") AS hour, COUNT(*) AS num
1919                                    FROM {log}
1920                                   WHERE userid = :userid
1921                                         AND time > $daystart $courseselect
1922                                GROUP BY FLOOR((time - $daystart)/". HOURSECS .") ", $params);
1923 }
1924
1925 /**
1926  * Returns an object with counts of failed login attempts
1927  *
1928  * Returns information about failed login attempts.  If the current user is
1929  * an admin, then two numbers are returned:  the number of attempts and the
1930  * number of accounts.  For non-admins, only the attempts on the given user
1931  * are shown.
1932  *
1933  * @global moodle_database $DB
1934  * @uses CONTEXT_SYSTEM
1935  * @param string $mode Either 'admin' or 'everybody'
1936  * @param string $username The username we are searching for
1937  * @param string $lastlogin The date from which we are searching
1938  * @return int
1939  */
1940 function count_login_failures($mode, $username, $lastlogin) {
1941     global $DB;
1942
1943     $params = array('mode'=>$mode, 'username'=>$username, 'lastlogin'=>$lastlogin);
1944     $select = "module='login' AND action='error' AND time > :lastlogin";
1945
1946     $count = new stdClass();
1947
1948     if (is_siteadmin()) {
1949         if ($count->attempts = $DB->count_records_select('log', $select, $params)) {
1950             $count->accounts = $DB->count_records_select('log', $select, $params, 'COUNT(DISTINCT info)');
1951             return $count;
1952         }
1953     } else if ($mode == 'everybody') {
1954         if ($count->attempts = $DB->count_records_select('log', "$select AND info = :username", $params)) {
1955             return $count;
1956         }
1957     }
1958     return NULL;
1959 }
1960
1961
1962 /// GENERAL HELPFUL THINGS  ///////////////////////////////////
1963
1964 /**
1965  * Dumps a given object's information for debugging purposes
1966  *
1967  * When used in a CLI script, the object's information is written to the standard
1968  * error output stream. When used in a web script, the object is dumped to a
1969  * pre-formatted block with the "notifytiny" CSS class.
1970  *
1971  * @param mixed $object The data to be printed
1972  * @return void output is echo'd
1973  */
1974 function print_object($object) {
1975
1976     // we may need a lot of memory here
1977     raise_memory_limit(MEMORY_EXTRA);
1978
1979     if (CLI_SCRIPT) {
1980         fwrite(STDERR, print_r($object, true));
1981         fwrite(STDERR, PHP_EOL);
1982     } else {
1983         echo html_writer::tag('pre', s(print_r($object, true)), array('class' => 'notifytiny'));
1984     }
1985 }
1986
1987 /**
1988  * This function is the official hook inside XMLDB stuff to delegate its debug to one
1989  * external function.
1990  *
1991  * Any script can avoid calls to this function by defining XMLDB_SKIP_DEBUG_HOOK before
1992  * using XMLDB classes. Obviously, also, if this function doesn't exist, it isn't invoked ;-)
1993  *
1994  * @uses DEBUG_DEVELOPER
1995  * @param string $message string contains the error message
1996  * @param object $object object XMLDB object that fired the debug
1997  */
1998 function xmldb_debug($message, $object) {
1999
2000     debugging($message, DEBUG_DEVELOPER);
2001 }
2002
2003 /**
2004  * @global object
2005  * @uses CONTEXT_COURSECAT
2006  * @return boolean Whether the user can create courses in any category in the system.
2007  */
2008 function user_can_create_courses() {
2009     global $DB;
2010     $catsrs = $DB->get_recordset('course_categories');
2011     foreach ($catsrs as $cat) {
2012         if (has_capability('moodle/course:create', get_context_instance(CONTEXT_COURSECAT, $cat->id))) {
2013             $catsrs->close();
2014             return true;
2015         }
2016     }
2017     $catsrs->close();
2018     return false;
2019 }