Merge branch 'w51_MDL-30761_m23_slowmysql' of git://github.com/skodak/moodle
[moodle.git] / lib / accesslib.php
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46808d7c 1<?php
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2// This file is part of Moodle - http://moodle.org/
3//
46808d7c 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.
117bd748 13//
46808d7c 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/>.
6cdd0f9c 16
92e53168 17/**
46808d7c 18 * This file contains functions for managing user access
19 *
cc3edaa4 20 * <b>Public API vs internals</b>
5a4e7398 21 *
92e53168 22 * General users probably only care about
23 *
dcd6a775 24 * Context handling
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25 * - context_course::instance($courseid), context_module::instance($cm->id), context_coursecat::instance($catid)
26 * - context::instance_by_id($contextid)
27 * - $context->get_parent_contexts();
28 * - $context->get_child_contexts();
5a4e7398 29 *
dcd6a775 30 * Whether the user can do something...
92e53168 31 * - has_capability()
8a1b1c32 32 * - has_any_capability()
33 * - has_all_capabilities()
efd6fce5 34 * - require_capability()
dcd6a775 35 * - require_login() (from moodlelib)
e922fe23 36 * - is_siteadmin()
dcd6a775 37 *
38 * What courses has this user access to?
e922fe23 39 * - get_enrolled_users()
dcd6a775 40 *
db70c4bd 41 * What users can do X in this context?
42 * - get_users_by_capability()
43 *
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44 * Modify roles
45 * - role_assign()
46 * - role_unassign()
47 * - role_unassign_all()
5a4e7398 48 *
92e53168 49 *
e922fe23 50 * Advanced - for internal use only
dcd6a775 51 * - load_all_capabilities()
52 * - reload_all_capabilities()
bb2c22bd 53 * - has_capability_in_accessdata()
dcd6a775 54 * - get_user_access_sitewide()
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55 * - load_course_context()
56 * - load_role_access_by_context()
57 * - etc.
dcd6a775 58 *
cc3edaa4 59 * <b>Name conventions</b>
5a4e7398 60 *
cc3edaa4 61 * "ctx" means context
92e53168 62 *
cc3edaa4 63 * <b>accessdata</b>
92e53168 64 *
65 * Access control data is held in the "accessdata" array
66 * which - for the logged-in user, will be in $USER->access
5a4e7398 67 *
d867e696 68 * For other users can be generated and passed around (but may also be cached
e922fe23 69 * against userid in $ACCESSLIB_PRIVATE->accessdatabyuser).
92e53168 70 *
bb2c22bd 71 * $accessdata is a multidimensional array, holding
5a4e7398 72 * role assignments (RAs), role-capabilities-perm sets
51be70d2 73 * (role defs) and a list of courses we have loaded
92e53168 74 * data for.
75 *
5a4e7398 76 * Things are keyed on "contextpaths" (the path field of
92e53168 77 * the context table) for fast walking up/down the tree.
cc3edaa4 78 * <code>
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79 * $accessdata['ra'][$contextpath] = array($roleid=>$roleid)
80 * [$contextpath] = array($roleid=>$roleid)
81 * [$contextpath] = array($roleid=>$roleid)
117bd748 82 * </code>
92e53168 83 *
84 * Role definitions are stored like this
85 * (no cap merge is done - so it's compact)
86 *
cc3edaa4 87 * <code>
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88 * $accessdata['rdef']["$contextpath:$roleid"]['mod/forum:viewpost'] = 1
89 * ['mod/forum:editallpost'] = -1
90 * ['mod/forum:startdiscussion'] = -1000
cc3edaa4 91 * </code>
92e53168 92 *
e922fe23 93 * See how has_capability_in_accessdata() walks up the tree.
92e53168 94 *
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95 * First we only load rdef and ra down to the course level, but not below.
96 * This keeps accessdata small and compact. Below-the-course ra/rdef
97 * are loaded as needed. We keep track of which courses we have loaded ra/rdef in
cc3edaa4 98 * <code>
e922fe23 99 * $accessdata['loaded'] = array($courseid1=>1, $courseid2=>1)
cc3edaa4 100 * </code>
92e53168 101 *
cc3edaa4 102 * <b>Stale accessdata</b>
92e53168 103 *
104 * For the logged-in user, accessdata is long-lived.
105 *
d867e696 106 * On each pageload we load $ACCESSLIB_PRIVATE->dirtycontexts which lists
92e53168 107 * context paths affected by changes. Any check at-or-below
108 * a dirty context will trigger a transparent reload of accessdata.
5a4e7398 109 *
4f65e0fb 110 * Changes at the system level will force the reload for everyone.
92e53168 111 *
cc3edaa4 112 * <b>Default role caps</b>
5a4e7398 113 * The default role assignment is not in the DB, so we
114 * add it manually to accessdata.
92e53168 115 *
116 * This means that functions that work directly off the
117 * DB need to ensure that the default role caps
5a4e7398 118 * are dealt with appropriately.
92e53168 119 *
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120 * @package core
121 * @subpackage role
122 * @copyright 1999 onwards Martin Dougiamas http://dougiamas.com
123 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
92e53168 124 */
bbbf2d40 125
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126defined('MOODLE_INTERNAL') || die();
127
e922fe23 128/** No capability change */
e49e61bf 129define('CAP_INHERIT', 0);
e922fe23 130/** Allow permission, overrides CAP_PREVENT defined in parent contexts */
bbbf2d40 131define('CAP_ALLOW', 1);
e922fe23 132/** Prevent permission, overrides CAP_ALLOW defined in parent contexts */
bbbf2d40 133define('CAP_PREVENT', -1);
e922fe23 134/** Prohibit permission, overrides everything in current and child contexts */
bbbf2d40 135define('CAP_PROHIBIT', -1000);
136
e922fe23 137/** System context level - only one instance in every system */
bbbf2d40 138define('CONTEXT_SYSTEM', 10);
e922fe23 139/** User context level - one instance for each user describing what others can do to user */
4b10f08b 140define('CONTEXT_USER', 30);
e922fe23 141/** Course category context level - one instance for each category */
bbbf2d40 142define('CONTEXT_COURSECAT', 40);
e922fe23 143/** Course context level - one instances for each course */
bbbf2d40 144define('CONTEXT_COURSE', 50);
e922fe23 145/** Course module context level - one instance for each course module */
bbbf2d40 146define('CONTEXT_MODULE', 70);
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147/**
148 * Block context level - one instance for each block, sticky blocks are tricky
149 * because ppl think they should be able to override them at lower contexts.
150 * Any other context level instance can be parent of block context.
151 */
bbbf2d40 152define('CONTEXT_BLOCK', 80);
153
e922fe23 154/** Capability allow management of trusts - NOT IMPLEMENTED YET - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
21b6db6e 155define('RISK_MANAGETRUST', 0x0001);
e922fe23 156/** Capability allows changes in system configuration - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
a6b02b65 157define('RISK_CONFIG', 0x0002);
e922fe23 158/** Capability allows user to add scritped content - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
21b6db6e 159define('RISK_XSS', 0x0004);
e922fe23 160/** Capability allows access to personal user information - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
21b6db6e 161define('RISK_PERSONAL', 0x0008);
e922fe23 162/** Capability allows users to add content otehrs may see - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
21b6db6e 163define('RISK_SPAM', 0x0010);
e922fe23 164/** capability allows mass delete of data belonging to other users - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
3a0c6cca 165define('RISK_DATALOSS', 0x0020);
21b6db6e 166
cc3edaa4 167/** rolename displays - the name as defined in the role definition */
168define('ROLENAME_ORIGINAL', 0);
169/** rolename displays - the name as defined by a role alias */
170define('ROLENAME_ALIAS', 1);
e922fe23 171/** rolename displays - Both, like this: Role alias (Original) */
cc3edaa4 172define('ROLENAME_BOTH', 2);
e922fe23 173/** rolename displays - the name as defined in the role definition and the shortname in brackets */
cc3edaa4 174define('ROLENAME_ORIGINALANDSHORT', 3);
e922fe23 175/** rolename displays - the name as defined by a role alias, in raw form suitable for editing */
cc3edaa4 176define('ROLENAME_ALIAS_RAW', 4);
e922fe23 177/** rolename displays - the name is simply short role name */
df997f84 178define('ROLENAME_SHORT', 5);
cc3edaa4 179
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180/** maximum size of context cache - it is possible to tweak this config.php or in any script before inclusion of context.php */
181if (!defined('CONTEXT_CACHE_MAX_SIZE')) {
182 define('CONTEXT_CACHE_MAX_SIZE', 2500);
4d10247f 183}
184
cc3edaa4 185/**
117bd748 186 * Although this looks like a global variable, it isn't really.
cc3edaa4 187 *
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188 * It is just a private implementation detail to accesslib that MUST NOT be used elsewhere.
189 * It is used to cache various bits of data between function calls for performance reasons.
4f65e0fb 190 * Sadly, a PHP global variable is the only way to implement this, without rewriting everything
cc3edaa4 191 * as methods of a class, instead of functions.
192 *
e922fe23 193 * @private
cc3edaa4 194 * @global stdClass $ACCESSLIB_PRIVATE
195 * @name $ACCESSLIB_PRIVATE
196 */
f14438dc 197global $ACCESSLIB_PRIVATE;
62e65b21 198$ACCESSLIB_PRIVATE = new stdClass();
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199$ACCESSLIB_PRIVATE->dirtycontexts = null; // Dirty contexts cache, loaded from DB once per page
200$ACCESSLIB_PRIVATE->accessdatabyuser = array(); // Holds the cache of $accessdata structure for users (including $USER)
201$ACCESSLIB_PRIVATE->rolepermissions = array(); // role permissions cache - helps a lot with mem usage
202$ACCESSLIB_PRIVATE->capabilities = null; // detailed information about the capabilities
bbbf2d40 203
d867e696 204/**
46808d7c 205 * Clears accesslib's private caches. ONLY BE USED BY UNIT TESTS
117bd748 206 *
d867e696 207 * This method should ONLY BE USED BY UNIT TESTS. It clears all of
208 * accesslib's private caches. You need to do this before setting up test data,
4f65e0fb 209 * and also at the end of the tests.
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210 *
211 * @return void
d867e696 212 */
213function accesslib_clear_all_caches_for_unit_testing() {
e922fe23 214 global $UNITTEST, $USER;
d867e696 215 if (empty($UNITTEST->running)) {
216 throw new coding_exception('You must not call clear_all_caches outside of unit tests.');
217 }
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218
219 accesslib_clear_all_caches(true);
d867e696 220
221 unset($USER->access);
222}
223
46808d7c 224/**
e922fe23 225 * Clears accesslib's private caches. ONLY BE USED FROM THIS LIBRARY FILE!
46808d7c 226 *
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227 * This reset does not touch global $USER.
228 *
229 * @private
230 * @param bool $resetcontexts
231 * @return void
46808d7c 232 */
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233function accesslib_clear_all_caches($resetcontexts) {
234 global $ACCESSLIB_PRIVATE;
e7876c1e 235
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236 $ACCESSLIB_PRIVATE->dirtycontexts = null;
237 $ACCESSLIB_PRIVATE->accessdatabyuser = array();
238 $ACCESSLIB_PRIVATE->rolepermissions = array();
239 $ACCESSLIB_PRIVATE->capabilities = null;
e7876c1e 240
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241 if ($resetcontexts) {
242 context_helper::reset_caches();
e7876c1e 243 }
eef879ec 244}
245
eef879ec 246/**
46808d7c 247 * Gets the accessdata for role "sitewide" (system down to course)
343effbe 248 *
e922fe23 249 * @private
46808d7c 250 * @param int $roleid
e0376a62 251 * @return array
eef879ec 252 */
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253function get_role_access($roleid) {
254 global $DB, $ACCESSLIB_PRIVATE;
eef879ec 255
e922fe23 256 /* Get it in 1 DB query...
e0376a62 257 * - relevant role caps at the root and down
258 * to the course level - but not below
259 */
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260
261 //TODO: MUC - this could be cached in shared memory to speed up first page loading, web crawlers, etc.
262
263 $accessdata = get_empty_accessdata();
264
265 $accessdata['ra']['/'.SYSCONTEXTID] = array((int)$roleid => (int)$roleid);
e7876c1e 266
e0376a62 267 //
268 // Overrides for the role IN ANY CONTEXTS
269 // down to COURSE - not below -
270 //
271 $sql = "SELECT ctx.path,
272 rc.capability, rc.permission
f33e1ed4 273 FROM {context} ctx
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274 JOIN {role_capabilities} rc ON rc.contextid = ctx.id
275 LEFT JOIN {context} cctx
276 ON (cctx.contextlevel = ".CONTEXT_COURSE." AND ctx.path LIKE ".$DB->sql_concat('cctx.path',"'/%'").")
277 WHERE rc.roleid = ? AND cctx.id IS NULL";
f33e1ed4 278 $params = array($roleid);
133d5a97 279
a91b910e 280 // we need extra caching in CLI scripts and cron
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281 $rs = $DB->get_recordset_sql($sql, $params);
282 foreach ($rs as $rd) {
283 $k = "{$rd->path}:{$roleid}";
284 $accessdata['rdef'][$k][$rd->capability] = (int)$rd->permission;
8d2b18a8 285 }
e922fe23 286 $rs->close();
e0376a62 287
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288 // share the role definitions
289 foreach ($accessdata['rdef'] as $k=>$unused) {
290 if (!isset($ACCESSLIB_PRIVATE->rolepermissions[$k])) {
291 $ACCESSLIB_PRIVATE->rolepermissions[$k] = $accessdata['rdef'][$k];
4e1fe7d1 292 }
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293 $accessdata['rdef_count']++;
294 $accessdata['rdef'][$k] =& $ACCESSLIB_PRIVATE->rolepermissions[$k];
4e1fe7d1 295 }
296
297 return $accessdata;
298}
299
8f8ed475 300/**
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301 * Get the default guest role, this is used for guest account,
302 * search engine spiders, etc.
117bd748 303 *
e922fe23 304 * @return stdClass role record
8f8ed475 305 */
306function get_guest_role() {
f33e1ed4 307 global $CFG, $DB;
ebce32b5 308
309 if (empty($CFG->guestroleid)) {
4f0c2d00 310 if ($roles = $DB->get_records('role', array('archetype'=>'guest'))) {
ebce32b5 311 $guestrole = array_shift($roles); // Pick the first one
312 set_config('guestroleid', $guestrole->id);
313 return $guestrole;
314 } else {
315 debugging('Can not find any guest role!');
316 return false;
317 }
8f8ed475 318 } else {
f33e1ed4 319 if ($guestrole = $DB->get_record('role', array('id'=>$CFG->guestroleid))) {
ebce32b5 320 return $guestrole;
321 } else {
e922fe23 322 // somebody is messing with guest roles, remove incorrect setting and try to find a new one
ebce32b5 323 set_config('guestroleid', '');
324 return get_guest_role();
325 }
8f8ed475 326 }
327}
328
128f0984 329/**
4f65e0fb 330 * Check whether a user has a particular capability in a given context.
46808d7c 331 *
e922fe23 332 * For example:
41e87d30 333 * $context = get_context_instance(CONTEXT_MODULE, $cm->id);
334 * has_capability('mod/forum:replypost',$context)
46808d7c 335 *
4f65e0fb 336 * By default checks the capabilities of the current user, but you can pass a
4f0c2d00
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337 * different userid. By default will return true for admin users, but you can override that with the fourth argument.
338 *
339 * Guest and not-logged-in users can never get any dangerous capability - that is any write capability
340 * or capabilities with XSS, config or data loss risks.
117bd748 341 *
41e87d30 342 * @param string $capability the name of the capability to check. For example mod/forum:view
e922fe23 343 * @param context $context the context to check the capability in. You normally get this with {@link get_context_instance}.
62e65b21 344 * @param integer|object $user A user id or object. By default (null) checks the permissions of the current user.
4f0c2d00 345 * @param boolean $doanything If false, ignores effect of admin role assignment
41e87d30 346 * @return boolean true if the user has this capability. Otherwise false.
128f0984 347 */
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348function has_capability($capability, context $context, $user = null, $doanything = true) {
349 global $USER, $CFG, $SCRIPT, $ACCESSLIB_PRIVATE;
18818abf 350
31a99877 351 if (during_initial_install()) {
e922fe23 352 if ($SCRIPT === "/$CFG->admin/index.php" or $SCRIPT === "/$CFG->admin/cli/install.php" or $SCRIPT === "/$CFG->admin/cli/install_database.php") {
18818abf 353 // we are in an installer - roles can not work yet
354 return true;
355 } else {
356 return false;
357 }
358 }
7f97ea29 359
4f0c2d00
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360 if (strpos($capability, 'moodle/legacy:') === 0) {
361 throw new coding_exception('Legacy capabilities can not be used any more!');
362 }
363
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364 if (!is_bool($doanything)) {
365 throw new coding_exception('Capability parameter "doanything" is wierd, only true or false is allowed. This has to be fixed in code.');
366 }
367
368 // capability must exist
369 if (!$capinfo = get_capability_info($capability)) {
370 debugging('Capability "'.$capability.'" was not found! This has to be fixed in code.');
7d0c81b3 371 return false;
74ac5b66 372 }
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373
374 if (!isset($USER->id)) {
375 // should never happen
376 $USER->id = 0;
4f0c2d00 377 }
7f97ea29 378
4f0c2d00 379 // make sure there is a real user specified
62e65b21 380 if ($user === null) {
e922fe23 381 $userid = $USER->id;
4f0c2d00 382 } else {
2b55aca7 383 $userid = is_object($user) ? $user->id : $user;
cc3d5e10 384 }
385
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386 // make sure forcelogin cuts off not-logged-in users if enabled
387 if (!empty($CFG->forcelogin) and $userid == 0) {
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388 return false;
389 }
e922fe23 390
4f0c2d00 391 // make sure the guest account and not-logged-in users never get any risky caps no matter what the actual settings are.
e922fe23 392 if (($capinfo->captype === 'write') or ($capinfo->riskbitmask & (RISK_XSS | RISK_CONFIG | RISK_DATALOSS))) {
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393 if (isguestuser($userid) or $userid == 0) {
394 return false;
c84a2dbe 395 }
7f97ea29 396 }
397
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398 // somehow make sure the user is not deleted and actually exists
399 if ($userid != 0) {
400 if ($userid == $USER->id and isset($USER->deleted)) {
401 // this prevents one query per page, it is a bit of cheating,
402 // but hopefully session is terminated properly once user is deleted
403 if ($USER->deleted) {
404 return false;
405 }
128f0984 406 } else {
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407 if (!context_user::instance($userid, IGNORE_MISSING)) {
408 // no user context == invalid userid
409 return false;
410 }
7be3be1b 411 }
148eb2a7 412 }
128f0984 413
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414 // context path/depth must be valid
415 if (empty($context->path) or $context->depth == 0) {
416 // this should not happen often, each upgrade tries to rebuild the context paths
417 debugging('Context id '.$context->id.' does not have valid path, please use build_context_path()');
418 if (is_siteadmin($userid)) {
419 return true;
128f0984 420 } else {
e922fe23 421 return false;
128f0984 422 }
148eb2a7 423 }
128f0984 424
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425 // Find out if user is admin - it is not possible to override the doanything in any way
426 // and it is not possible to switch to admin role either.
427 if ($doanything) {
428 if (is_siteadmin($userid)) {
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429 if ($userid != $USER->id) {
430 return true;
431 }
432 // make sure switchrole is not used in this context
433 if (empty($USER->access['rsw'])) {
434 return true;
435 }
436 $parts = explode('/', trim($context->path, '/'));
437 $path = '';
438 $switched = false;
439 foreach ($parts as $part) {
440 $path .= '/' . $part;
441 if (!empty($USER->access['rsw'][$path])) {
442 $switched = true;
443 break;
444 }
445 }
446 if (!$switched) {
447 return true;
448 }
449 //ok, admin switched role in this context, let's use normal access control rules
4f0c2d00
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450 }
451 }
452
e922fe23
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453 // Careful check for staleness...
454 $context->reload_if_dirty();
13a79475 455
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456 if ($USER->id == $userid) {
457 if (!isset($USER->access)) {
458 load_all_capabilities();
7f97ea29 459 }
e922fe23 460 $access =& $USER->access;
bb2c22bd 461
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462 } else {
463 // make sure user accessdata is really loaded
464 get_user_accessdata($userid, true);
465 $access =& $ACCESSLIB_PRIVATE->accessdatabyuser[$userid];
204a369c 466 }
4f0c2d00 467
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468
469 // Load accessdata for below-the-course context if necessary,
470 // all contexts at and above all courses are already loaded
471 if ($context->contextlevel != CONTEXT_COURSE and $coursecontext = $context->get_course_context(false)) {
472 load_course_context($userid, $coursecontext, $access);
420bfab1 473 }
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474
475 return has_capability_in_accessdata($capability, $context, $access);
7f97ea29 476}
477
3fc3ebf2 478/**
41e87d30 479 * Check if the user has any one of several capabilities from a list.
46808d7c 480 *
41e87d30 481 * This is just a utility method that calls has_capability in a loop. Try to put
482 * the capabilities that most users are likely to have first in the list for best
483 * performance.
3fc3ebf2 484 *
46808d7c 485 * @see has_capability()
41e87d30 486 * @param array $capabilities an array of capability names.
e922fe23 487 * @param context $context the context to check the capability in. You normally get this with {@link get_context_instance}.
62e65b21 488 * @param integer $userid A user id. By default (null) checks the permissions of the current user.
4f0c2d00 489 * @param boolean $doanything If false, ignore effect of admin role assignment
41e87d30 490 * @return boolean true if the user has any of these capabilities. Otherwise false.
3fc3ebf2 491 */
e922fe23 492function has_any_capability(array $capabilities, context $context, $userid = null, $doanything = true) {
3fc3ebf2 493 foreach ($capabilities as $capability) {
59664877 494 if (has_capability($capability, $context, $userid, $doanything)) {
3fc3ebf2 495 return true;
496 }
497 }
498 return false;
499}
500
8a1b1c32 501/**
41e87d30 502 * Check if the user has all the capabilities in a list.
46808d7c 503 *
41e87d30 504 * This is just a utility method that calls has_capability in a loop. Try to put
505 * the capabilities that fewest users are likely to have first in the list for best
506 * performance.
8a1b1c32 507 *
46808d7c 508 * @see has_capability()
41e87d30 509 * @param array $capabilities an array of capability names.
e922fe23 510 * @param context $context the context to check the capability in. You normally get this with {@link get_context_instance}.
62e65b21 511 * @param integer $userid A user id. By default (null) checks the permissions of the current user.
4f0c2d00 512 * @param boolean $doanything If false, ignore effect of admin role assignment
41e87d30 513 * @return boolean true if the user has all of these capabilities. Otherwise false.
8a1b1c32 514 */
e922fe23 515function has_all_capabilities(array $capabilities, context $context, $userid = null, $doanything = true) {
8a1b1c32 516 foreach ($capabilities as $capability) {
517 if (!has_capability($capability, $context, $userid, $doanything)) {
518 return false;
519 }
520 }
521 return true;
522}
523
128f0984 524/**
4f0c2d00 525 * Check if the user is an admin at the site level.
46808d7c 526 *
4f0c2d00
PS
527 * Please note that use of proper capabilities is always encouraged,
528 * this function is supposed to be used from core or for temporary hacks.
39407442 529 *
e922fe23
PS
530 * @param int|stdClass $user_or_id user id or user object
531 * @return bool true if user is one of the administrators, false otherwise
39407442 532 */
62e65b21 533function is_siteadmin($user_or_id = null) {
4f0c2d00 534 global $CFG, $USER;
39407442 535
62e65b21 536 if ($user_or_id === null) {
4f0c2d00
PS
537 $user_or_id = $USER;
538 }
6cab02ac 539
4f0c2d00
PS
540 if (empty($user_or_id)) {
541 return false;
542 }
543 if (!empty($user_or_id->id)) {
4f0c2d00
PS
544 $userid = $user_or_id->id;
545 } else {
546 $userid = $user_or_id;
547 }
6cab02ac 548
4f0c2d00
PS
549 $siteadmins = explode(',', $CFG->siteadmins);
550 return in_array($userid, $siteadmins);
6cab02ac 551}
552
bbdb7070 553/**
4f0c2d00 554 * Returns true if user has at least one role assign
df997f84 555 * of 'coursecontact' role (is potentially listed in some course descriptions).
62e65b21 556 *
e922fe23
PS
557 * @param int $userid
558 * @return bool
bbdb7070 559 */
df997f84 560function has_coursecontact_role($userid) {
2fb34345 561 global $DB, $CFG;
bbdb7070 562
df997f84 563 if (empty($CFG->coursecontact)) {
4f0c2d00
PS
564 return false;
565 }
566 $sql = "SELECT 1
567 FROM {role_assignments}
df997f84 568 WHERE userid = :userid AND roleid IN ($CFG->coursecontact)";
b2cd6570 569 return $DB->record_exists_sql($sql, array('userid'=>$userid));
bbdb7070 570}
571
128f0984 572/**
01a2ce80 573 * Does the user have a capability to do something?
46808d7c 574 *
31c2de82 575 * Walk the accessdata array and return true/false.
e922fe23 576 * Deals with prohibits, role switching, aggregating
6a8d9a38 577 * capabilities, etc.
578 *
579 * The main feature of here is being FAST and with no
5a4e7398 580 * side effects.
6a8d9a38 581 *
3ac81bd1 582 * Notes:
583 *
3d034f77 584 * Switch Role merges with default role
585 * ------------------------------------
586 * If you are a teacher in course X, you have at least
587 * teacher-in-X + defaultloggedinuser-sitewide. So in the
588 * course you'll have techer+defaultloggedinuser.
589 * We try to mimic that in switchrole.
590 *
01a2ce80
PS
591 * Permission evaluation
592 * ---------------------
4f65e0fb 593 * Originally there was an extremely complicated way
01a2ce80 594 * to determine the user access that dealt with
4f65e0fb
PS
595 * "locality" or role assignments and role overrides.
596 * Now we simply evaluate access for each role separately
01a2ce80
PS
597 * and then verify if user has at least one role with allow
598 * and at the same time no role with prohibit.
599 *
e922fe23 600 * @private
46808d7c 601 * @param string $capability
e922fe23 602 * @param context $context
46808d7c 603 * @param array $accessdata
46808d7c 604 * @return bool
6a8d9a38 605 */
e922fe23 606function has_capability_in_accessdata($capability, context $context, array &$accessdata) {
3ac81bd1 607 global $CFG;
608
01a2ce80 609 // Build $paths as a list of current + all parent "paths" with order bottom-to-top
e922fe23
PS
610 $path = $context->path;
611 $paths = array($path);
612 while($path = rtrim($path, '0123456789')) {
613 $path = rtrim($path, '/');
614 if ($path === '') {
615 break;
616 }
617 $paths[] = $path;
3ac81bd1 618 }
619
01a2ce80
PS
620 $roles = array();
621 $switchedrole = false;
6a8d9a38 622
01a2ce80
PS
623 // Find out if role switched
624 if (!empty($accessdata['rsw'])) {
6a8d9a38 625 // From the bottom up...
01a2ce80 626 foreach ($paths as $path) {
1209cb5c 627 if (isset($accessdata['rsw'][$path])) {
01a2ce80 628 // Found a switchrole assignment - check for that role _plus_ the default user role
62e65b21 629 $roles = array($accessdata['rsw'][$path]=>null, $CFG->defaultuserroleid=>null);
01a2ce80
PS
630 $switchedrole = true;
631 break;
6a8d9a38 632 }
633 }
634 }
635
01a2ce80
PS
636 if (!$switchedrole) {
637 // get all users roles in this context and above
638 foreach ($paths as $path) {
639 if (isset($accessdata['ra'][$path])) {
640 foreach ($accessdata['ra'][$path] as $roleid) {
62e65b21 641 $roles[$roleid] = null;
7f97ea29 642 }
01a2ce80
PS
643 }
644 }
7f97ea29 645 }
646
01a2ce80 647 // Now find out what access is given to each role, going bottom-->up direction
e922fe23 648 $allowed = false;
01a2ce80
PS
649 foreach ($roles as $roleid => $ignored) {
650 foreach ($paths as $path) {
651 if (isset($accessdata['rdef']["{$path}:$roleid"][$capability])) {
652 $perm = (int)$accessdata['rdef']["{$path}:$roleid"][$capability];
e922fe23
PS
653 if ($perm === CAP_PROHIBIT) {
654 // any CAP_PROHIBIT found means no permission for the user
655 return false;
656 }
657 if (is_null($roles[$roleid])) {
01a2ce80
PS
658 $roles[$roleid] = $perm;
659 }
660 }
7f97ea29 661 }
e922fe23
PS
662 // CAP_ALLOW in any role means the user has a permission, we continue only to detect prohibits
663 $allowed = ($allowed or $roles[$roleid] === CAP_ALLOW);
7f97ea29 664 }
665
e922fe23 666 return $allowed;
018d4b52 667}
668
0468976c 669/**
41e87d30 670 * A convenience function that tests has_capability, and displays an error if
671 * the user does not have that capability.
8a9c1c1c 672 *
41e87d30 673 * NOTE before Moodle 2.0, this function attempted to make an appropriate
674 * require_login call before checking the capability. This is no longer the case.
675 * You must call require_login (or one of its variants) if you want to check the
676 * user is logged in, before you call this function.
efd6fce5 677 *
46808d7c 678 * @see has_capability()
679 *
41e87d30 680 * @param string $capability the name of the capability to check. For example mod/forum:view
e922fe23
PS
681 * @param context $context the context to check the capability in. You normally get this with {@link get_context_instance}.
682 * @param int $userid A user id. By default (null) checks the permissions of the current user.
4f0c2d00 683 * @param bool $doanything If false, ignore effect of admin role assignment
e922fe23 684 * @param string $errormessage The error string to to user. Defaults to 'nopermissions'.
41e87d30 685 * @param string $stringfile The language file to load the error string from. Defaults to 'error'.
686 * @return void terminates with an error if the user does not have the given capability.
0468976c 687 */
e922fe23 688function require_capability($capability, context $context, $userid = null, $doanything = true,
41e87d30 689 $errormessage = 'nopermissions', $stringfile = '') {
d74067e8 690 if (!has_capability($capability, $context, $userid, $doanything)) {
9a0df45a 691 throw new required_capability_exception($context, $capability, $errormessage, $stringfile);
0468976c 692 }
693}
694
a9bee37e 695/**
46808d7c 696 * Return a nested array showing role assignments
a9bee37e 697 * all relevant role capabilities for the user at
df997f84 698 * site/course_category/course levels
a9bee37e 699 *
700 * We do _not_ delve deeper than courses because the number of
e922fe23 701 * overrides at the module/block levels can be HUGE.
a9bee37e 702 *
e922fe23
PS
703 * [ra] => [/path][roleid]=roleid
704 * [rdef] => [/path:roleid][capability]=permission
a9bee37e 705 *
e922fe23 706 * @private
62e65b21 707 * @param int $userid - the id of the user
e922fe23 708 * @return array access info array
a9bee37e 709 */
74ac5b66 710function get_user_access_sitewide($userid) {
e922fe23 711 global $CFG, $DB, $ACCESSLIB_PRIVATE;
a9bee37e 712
e922fe23 713 /* Get in a few cheap DB queries...
f5930992 714 * - role assignments
a9bee37e 715 * - relevant role caps
f5930992 716 * - above and within this user's RAs
a9bee37e 717 * - below this user's RAs - limited to course level
718 */
719
e922fe23
PS
720 // raparents collects paths & roles we need to walk up the parenthood to build the minimal rdef
721 $raparents = array();
722 $accessdata = get_empty_accessdata();
a9bee37e 723
e922fe23
PS
724 // start with the default role
725 if (!empty($CFG->defaultuserroleid)) {
726 $syscontext = context_system::instance();
727 $accessdata['ra'][$syscontext->path][(int)$CFG->defaultuserroleid] = (int)$CFG->defaultuserroleid;
e7f2c2cc 728 $raparents[$CFG->defaultuserroleid][$syscontext->id] = $syscontext->id;
e922fe23
PS
729 }
730
731 // load the "default frontpage role"
732 if (!empty($CFG->defaultfrontpageroleid)) {
733 $frontpagecontext = context_course::instance(get_site()->id);
734 if ($frontpagecontext->path) {
735 $accessdata['ra'][$frontpagecontext->path][(int)$CFG->defaultfrontpageroleid] = (int)$CFG->defaultfrontpageroleid;
e7f2c2cc 736 $raparents[$CFG->defaultfrontpageroleid][$frontpagecontext->id] = $frontpagecontext->id;
e922fe23
PS
737 }
738 }
739
740 // preload every assigned role at and above course context
e7f2c2cc 741 $sql = "SELECT ctx.path, ra.roleid, ra.contextid
f33e1ed4 742 FROM {role_assignments} ra
e7f2c2cc
PS
743 JOIN {context} ctx
744 ON ctx.id = ra.contextid
745 LEFT JOIN {block_instances} bi
746 ON (ctx.contextlevel = ".CONTEXT_BLOCK." AND bi.id = ctx.instanceid)
747 LEFT JOIN {context} bpctx
748 ON (bpctx.id = bi.parentcontextid)
749 WHERE ra.userid = :userid
750 AND (ctx.contextlevel <= ".CONTEXT_COURSE." OR bpctx.contextlevel < ".CONTEXT_COURSE.")";
e922fe23
PS
751 $params = array('userid'=>$userid);
752 $rs = $DB->get_recordset_sql($sql, $params);
753 foreach ($rs as $ra) {
754 // RAs leafs are arrays to support multi-role assignments...
755 $accessdata['ra'][$ra->path][(int)$ra->roleid] = (int)$ra->roleid;
e7f2c2cc 756 $raparents[$ra->roleid][$ra->contextid] = $ra->contextid;
a9bee37e 757 }
e922fe23 758 $rs->close();
a9bee37e 759
e922fe23
PS
760 if (empty($raparents)) {
761 return $accessdata;
a9bee37e 762 }
f5930992 763
e922fe23
PS
764 // now get overrides of interesting roles in all interesting child contexts
765 // hopefully we will not run out of SQL limits here,
e7f2c2cc 766 // users would have to have very many roles at/above course context...
e922fe23
PS
767 $sqls = array();
768 $params = array();
f5930992 769
e922fe23 770 static $cp = 0;
e7f2c2cc 771 foreach ($raparents as $roleid=>$ras) {
e922fe23 772 $cp++;
e7f2c2cc
PS
773 list($sqlcids, $cids) = $DB->get_in_or_equal($ras, SQL_PARAMS_NAMED, 'c'.$cp.'_');
774 $params = array_merge($params, $cids);
e922fe23
PS
775 $params['r'.$cp] = $roleid;
776 $sqls[] = "(SELECT ctx.path, rc.roleid, rc.capability, rc.permission
777 FROM {role_capabilities} rc
778 JOIN {context} ctx
779 ON (ctx.id = rc.contextid)
e922fe23 780 JOIN {context} pctx
e7f2c2cc 781 ON (pctx.id $sqlcids
e922fe23
PS
782 AND (ctx.id = pctx.id
783 OR ctx.path LIKE ".$DB->sql_concat('pctx.path',"'/%'")."
784 OR pctx.path LIKE ".$DB->sql_concat('ctx.path',"'/%'")."))
e7f2c2cc
PS
785 LEFT JOIN {block_instances} bi
786 ON (ctx.contextlevel = ".CONTEXT_BLOCK." AND bi.id = ctx.instanceid)
787 LEFT JOIN {context} bpctx
788 ON (bpctx.id = bi.parentcontextid)
e922fe23 789 WHERE rc.roleid = :r{$cp}
e7f2c2cc
PS
790 AND (ctx.contextlevel <= ".CONTEXT_COURSE." OR bpctx.contextlevel < ".CONTEXT_COURSE.")
791 )";
e922fe23
PS
792 }
793
794 // fixed capability order is necessary for rdef dedupe
795 $rs = $DB->get_recordset_sql(implode("\nUNION\n", $sqls). "ORDER BY capability", $params);
a9bee37e 796
e922fe23
PS
797 foreach ($rs as $rd) {
798 $k = $rd->path.':'.$rd->roleid;
799 $accessdata['rdef'][$k][$rd->capability] = (int)$rd->permission;
a9bee37e 800 }
e922fe23 801 $rs->close();
a9bee37e 802
e922fe23
PS
803 // share the role definitions
804 foreach ($accessdata['rdef'] as $k=>$unused) {
805 if (!isset($ACCESSLIB_PRIVATE->rolepermissions[$k])) {
806 $ACCESSLIB_PRIVATE->rolepermissions[$k] = $accessdata['rdef'][$k];
0dbb2191 807 }
e922fe23
PS
808 $accessdata['rdef_count']++;
809 $accessdata['rdef'][$k] =& $ACCESSLIB_PRIVATE->rolepermissions[$k];
a9bee37e 810 }
e922fe23 811
bb2c22bd 812 return $accessdata;
a9bee37e 813}
814
74ac5b66 815/**
e922fe23 816 * Add to the access ctrl array the data needed by a user for a given course.
74ac5b66 817 *
e922fe23
PS
818 * This function injects all course related access info into the accessdata array.
819 *
820 * @private
821 * @param int $userid the id of the user
822 * @param context_course $coursecontext course context
823 * @param array $accessdata accessdata array (modified)
824 * @return void modifies $accessdata parameter
74ac5b66 825 */
e922fe23
PS
826function load_course_context($userid, context_course $coursecontext, &$accessdata) {
827 global $DB, $CFG, $ACCESSLIB_PRIVATE;
018d4b52 828
e922fe23
PS
829 if (empty($coursecontext->path)) {
830 // weird, this should not happen
831 return;
832 }
74ac5b66 833
e922fe23
PS
834 if (isset($accessdata['loaded'][$coursecontext->instanceid])) {
835 // already loaded, great!
836 return;
837 }
74ac5b66 838
e922fe23 839 $roles = array();
5a4e7398 840
e922fe23
PS
841 if (empty($userid)) {
842 if (!empty($CFG->notloggedinroleid)) {
843 $roles[$CFG->notloggedinroleid] = $CFG->notloggedinroleid;
844 }
74ac5b66 845
e922fe23
PS
846 } else if (isguestuser($userid)) {
847 if ($guestrole = get_guest_role()) {
848 $roles[$guestrole->id] = $guestrole->id;
849 }
74ac5b66 850
e922fe23
PS
851 } else {
852 // Interesting role assignments at, above and below the course context
853 list($parentsaself, $params) = $DB->get_in_or_equal($coursecontext->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'pc_');
854 $params['userid'] = $userid;
855 $params['children'] = $coursecontext->path."/%";
856 $sql = "SELECT ra.*, ctx.path
857 FROM {role_assignments} ra
858 JOIN {context} ctx ON ra.contextid = ctx.id
859 WHERE ra.userid = :userid AND (ctx.id $parentsaself OR ctx.path LIKE :children)";
860 $rs = $DB->get_recordset_sql($sql, $params);
861
862 // add missing role definitions
f33e1ed4 863 foreach ($rs as $ra) {
e922fe23
PS
864 $accessdata['ra'][$ra->path][(int)$ra->roleid] = (int)$ra->roleid;
865 $roles[$ra->roleid] = $ra->roleid;
74ac5b66 866 }
f33e1ed4 867 $rs->close();
74ac5b66 868
e922fe23
PS
869 // add the "default frontpage role" when on the frontpage
870 if (!empty($CFG->defaultfrontpageroleid)) {
871 $frontpagecontext = context_course::instance(get_site()->id);
872 if ($frontpagecontext->id == $coursecontext->id) {
873 $roles[$CFG->defaultfrontpageroleid] = $CFG->defaultfrontpageroleid;
874 }
875 }
53fb75dc 876
e922fe23
PS
877 // do not forget the default role
878 if (!empty($CFG->defaultuserroleid)) {
879 $roles[$CFG->defaultuserroleid] = $CFG->defaultuserroleid;
880 }
74ac5b66 881 }
882
e922fe23
PS
883 if (!$roles) {
884 // weird, default roles must be missing...
885 $accessdata['loaded'][$coursecontext->instanceid] = 1;
886 return;
7e17f43b 887 }
e922fe23
PS
888
889 // now get overrides of interesting roles in all interesting contexts (this course + children + parents)
890 $params = array('c'=>$coursecontext->id);
891 list($parentsaself, $rparams) = $DB->get_in_or_equal($coursecontext->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'pc_');
892 $params = array_merge($params, $rparams);
893 list($roleids, $rparams) = $DB->get_in_or_equal($roles, SQL_PARAMS_NAMED, 'r_');
894 $params = array_merge($params, $rparams);
895
53fb75dc 896 $sql = "SELECT ctx.path, rc.roleid, rc.capability, rc.permission
e922fe23
PS
897 FROM {role_capabilities} rc
898 JOIN {context} ctx
899 ON (ctx.id = rc.contextid)
900 JOIN {context} cctx
901 ON (cctx.id = :c
902 AND (ctx.id $parentsaself OR ctx.path LIKE ".$DB->sql_concat('cctx.path',"'/%'")."))
903 WHERE rc.roleid $roleids
904 ORDER BY rc.capability"; // fixed capability order is necessary for rdef dedupe
905 $rs = $DB->get_recordset_sql($sql, $params);
53fb75dc 906
a2cf7f1b 907 $newrdefs = array();
afa559e9 908 foreach ($rs as $rd) {
e922fe23
PS
909 $k = $rd->path.':'.$rd->roleid;
910 if (isset($accessdata['rdef'][$k])) {
911 continue;
74ac5b66 912 }
e922fe23 913 $newrdefs[$k][$rd->capability] = (int)$rd->permission;
74ac5b66 914 }
afa559e9 915 $rs->close();
74ac5b66 916
e922fe23
PS
917 // share new role definitions
918 foreach ($newrdefs as $k=>$unused) {
919 if (!isset($ACCESSLIB_PRIVATE->rolepermissions[$k])) {
920 $ACCESSLIB_PRIVATE->rolepermissions[$k] = $newrdefs[$k];
921 }
922 $accessdata['rdef_count']++;
923 $accessdata['rdef'][$k] =& $ACCESSLIB_PRIVATE->rolepermissions[$k];
a2cf7f1b 924 }
74ac5b66 925
e922fe23
PS
926 $accessdata['loaded'][$coursecontext->instanceid] = 1;
927
928 // we want to deduplicate the USER->access from time to time, this looks like a good place,
929 // because we have to do it before the end of session
930 dedupe_user_access();
74ac5b66 931}
2f1a4248 932
eef879ec 933/**
46808d7c 934 * Add to the access ctrl array the data needed by a role for a given context.
6f1bce30 935 *
936 * The data is added in the rdef key.
6f1bce30 937 * This role-centric function is useful for role_switching
e922fe23 938 * and temporary course roles.
6f1bce30 939 *
e922fe23
PS
940 * @private
941 * @param int $roleid the id of the user
942 * @param context $context needs path!
943 * @param array $accessdata accessdata array (is modified)
46808d7c 944 * @return array
6f1bce30 945 */
e922fe23
PS
946function load_role_access_by_context($roleid, context $context, &$accessdata) {
947 global $DB, $ACCESSLIB_PRIVATE;
6f1bce30 948
949 /* Get the relevant rolecaps into rdef
950 * - relevant role caps
951 * - at ctx and above
952 * - below this ctx
953 */
954
e922fe23
PS
955 if (empty($context->path)) {
956 // weird, this should not happen
957 return;
6f1bce30 958 }
5a4e7398 959
e922fe23
PS
960 list($parentsaself, $params) = $DB->get_in_or_equal($context->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'pc_');
961 $params['roleid'] = $roleid;
962 $params['childpath'] = $context->path.'/%';
6f1bce30 963
6f1bce30 964 $sql = "SELECT ctx.path, rc.capability, rc.permission
f33e1ed4 965 FROM {role_capabilities} rc
e922fe23
PS
966 JOIN {context} ctx ON (rc.contextid = ctx.id)
967 WHERE rc.roleid = :roleid AND (ctx.id $parentsaself OR ctx.path LIKE :childpath)
968 ORDER BY rc.capability"; // fixed capability order is necessary for rdef dedupe
afa559e9 969 $rs = $DB->get_recordset_sql($sql, $params);
e922fe23
PS
970
971 $newrdefs = array();
afa559e9 972 foreach ($rs as $rd) {
e922fe23
PS
973 $k = $rd->path.':'.$roleid;
974 if (isset($accessdata['rdef'][$k])) {
975 continue;
976 }
977 $newrdefs[$k][$rd->capability] = (int)$rd->permission;
6f1bce30 978 }
afa559e9 979 $rs->close();
6f1bce30 980
e922fe23
PS
981 // share new role definitions
982 foreach ($newrdefs as $k=>$unused) {
983 if (!isset($ACCESSLIB_PRIVATE->rolepermissions[$k])) {
984 $ACCESSLIB_PRIVATE->rolepermissions[$k] = $newrdefs[$k];
985 }
986 $accessdata['rdef_count']++;
987 $accessdata['rdef'][$k] =& $ACCESSLIB_PRIVATE->rolepermissions[$k];
988 }
989}
990
991/**
992 * Returns empty accessdata structure.
99ddfdf4
PS
993 *
994 * @private
e922fe23
PS
995 * @return array empt accessdata
996 */
997function get_empty_accessdata() {
998 $accessdata = array(); // named list
999 $accessdata['ra'] = array();
1000 $accessdata['rdef'] = array();
1001 $accessdata['rdef_count'] = 0; // this bloody hack is necessary because count($array) is slooooowwww in PHP
1002 $accessdata['rdef_lcc'] = 0; // rdef_count during the last compression
1003 $accessdata['loaded'] = array(); // loaded course contexts
1004 $accessdata['time'] = time();
1005
bb2c22bd 1006 return $accessdata;
6f1bce30 1007}
1008
a2cf7f1b 1009/**
e922fe23 1010 * Get accessdata for a given user.
204a369c 1011 *
e922fe23 1012 * @private
46808d7c 1013 * @param int $userid
e922fe23
PS
1014 * @param bool $preloadonly true means do not return access array
1015 * @return array accessdata
5a4e7398 1016 */
e922fe23
PS
1017function get_user_accessdata($userid, $preloadonly=false) {
1018 global $CFG, $ACCESSLIB_PRIVATE, $USER;
204a369c 1019
e922fe23
PS
1020 if (!empty($USER->acces['rdef']) and empty($ACCESSLIB_PRIVATE->rolepermissions)) {
1021 // share rdef from USER session with rolepermissions cache in order to conserve memory
1022 foreach($USER->acces['rdef'] as $k=>$v) {
1023 $ACCESSLIB_PRIVATE->rolepermissions[$k] =& $USER->acces['rdef'][$k];
7d0c81b3 1024 }
e922fe23 1025 $ACCESSLIB_PRIVATE->accessdatabyuser[$USER->id] = $USER->acces;
204a369c 1026 }
1027
e922fe23
PS
1028 if (!isset($ACCESSLIB_PRIVATE->accessdatabyuser[$userid])) {
1029 if (empty($userid)) {
1030 if (!empty($CFG->notloggedinroleid)) {
1031 $accessdata = get_role_access($CFG->notloggedinroleid);
1032 } else {
1033 // weird
1034 return get_empty_accessdata();
1035 }
1036
1037 } else if (isguestuser($userid)) {
1038 if ($guestrole = get_guest_role()) {
1039 $accessdata = get_role_access($guestrole->id);
1040 } else {
1041 //weird
1042 return get_empty_accessdata();
1043 }
1044
1045 } else {
1046 $accessdata = get_user_access_sitewide($userid); // includes default role and frontpage role
4e1fe7d1 1047 }
128f0984 1048
e922fe23
PS
1049 $ACCESSLIB_PRIVATE->accessdatabyuser[$userid] = $accessdata;
1050 }
a2cf7f1b 1051
e922fe23
PS
1052 if ($preloadonly) {
1053 return;
1054 } else {
1055 return $ACCESSLIB_PRIVATE->accessdatabyuser[$userid];
1056 }
204a369c 1057}
ef989bd9 1058
a2cf7f1b 1059/**
e922fe23
PS
1060 * Try to minimise the size of $USER->access by eliminating duplicate override storage,
1061 * this function looks for contexts with the same overrides and shares them.
cc3edaa4 1062 *
e922fe23
PS
1063 * @private
1064 * @return void
a2cf7f1b 1065 */
e922fe23
PS
1066function dedupe_user_access() {
1067 global $USER;
a2cf7f1b 1068
e922fe23
PS
1069 if (CLI_SCRIPT) {
1070 // no session in CLI --> no compression necessary
1071 return;
1072 }
a2cf7f1b 1073
e922fe23
PS
1074 if (empty($USER->access['rdef_count'])) {
1075 // weird, this should not happen
1076 return;
1077 }
1078
1079 // the rdef is growing only, we never remove stuff from it, the rdef_lcc helps us to detect new stuff in rdef
1080 if ($USER->access['rdef_count'] - $USER->access['rdef_lcc'] > 10) {
1081 // do not compress after each change, wait till there is more stuff to be done
1082 return;
1083 }
1084
1085 $hashmap = array();
1086 foreach ($USER->access['rdef'] as $k=>$def) {
1087 $hash = sha1(serialize($def));
1088 if (isset($hashmap[$hash])) {
1089 $USER->access['rdef'][$k] =& $hashmap[$hash];
1090 } else {
1091 $hashmap[$hash] =& $USER->access['rdef'][$k];
a2cf7f1b 1092 }
a2cf7f1b 1093 }
e922fe23
PS
1094
1095 $USER->access['rdef_lcc'] = $USER->access['rdef_count'];
a2cf7f1b 1096}
1097
6f1bce30 1098/**
46808d7c 1099 * A convenience function to completely load all the capabilities
e922fe23
PS
1100 * for the current user. It is called from has_capability() and functions change permissions.
1101 *
1102 * Call it only _after_ you've setup $USER and called check_enrolment_plugins();
46808d7c 1103 * @see check_enrolment_plugins()
117bd748 1104 *
e922fe23 1105 * @private
62e65b21 1106 * @return void
2f1a4248 1107 */
1108function load_all_capabilities() {
e922fe23 1109 global $USER;
bbbf2d40 1110
18818abf 1111 // roles not installed yet - we are in the middle of installation
31a99877 1112 if (during_initial_install()) {
1045a007 1113 return;
1114 }
1115
e922fe23
PS
1116 if (!isset($USER->id)) {
1117 // this should not happen
1118 $USER->id = 0;
2f1a4248 1119 }
55e68c29 1120
e922fe23
PS
1121 unset($USER->access);
1122 $USER->access = get_user_accessdata($USER->id);
1123
1124 // deduplicate the overrides to minimize session size
1125 dedupe_user_access();
55e68c29 1126
1127 // Clear to force a refresh
e922fe23 1128 unset($USER->mycourses);
bbfdff34
PS
1129
1130 // init/reset internal enrol caches - active course enrolments and temp access
1131 $USER->enrol = array('enrolled'=>array(), 'tempguest'=>array());
bbbf2d40 1132}
1133
ef989bd9 1134/**
5a4e7398 1135 * A convenience function to completely reload all the capabilities
ef989bd9 1136 * for the current user when roles have been updated in a relevant
5a4e7398 1137 * context -- but PRESERVING switchroles and loginas.
e922fe23 1138 * This function resets all accesslib and context caches.
ef989bd9 1139 *
1140 * That is - completely transparent to the user.
5a4e7398 1141 *
e922fe23 1142 * Note: reloads $USER->access completely.
ef989bd9 1143 *
e922fe23 1144 * @private
62e65b21 1145 * @return void
ef989bd9 1146 */
1147function reload_all_capabilities() {
e922fe23 1148 global $USER, $DB, $ACCESSLIB_PRIVATE;
ef989bd9 1149
ef989bd9 1150 // copy switchroles
1151 $sw = array();
1152 if (isset($USER->access['rsw'])) {
1153 $sw = $USER->access['rsw'];
ef989bd9 1154 }
1155
e922fe23 1156 accesslib_clear_all_caches(true);
ef989bd9 1157 unset($USER->access);
e922fe23 1158 $ACCESSLIB_PRIVATE->dirtycontexts = array(); // prevent dirty flags refetching on this page
5a4e7398 1159
ef989bd9 1160 load_all_capabilities();
1161
1162 foreach ($sw as $path => $roleid) {
e922fe23
PS
1163 if ($record = $DB->get_record('context', array('path'=>$path))) {
1164 $context = context::instance_by_id($record->id);
1165 role_switch($roleid, $context);
1166 }
ef989bd9 1167 }
ef989bd9 1168}
2f1a4248 1169
f33e1ed4 1170/**
e922fe23 1171 * Adds a temp role to current USER->access array.
343effbe 1172 *
e922fe23 1173 * Useful for the "temporary guest" access we grant to logged-in users.
99ddfdf4 1174 * @since 2.2
343effbe 1175 *
e922fe23 1176 * @param context_course $coursecontext
46808d7c 1177 * @param int $roleid
e922fe23 1178 * @return void
343effbe 1179 */
e922fe23 1180function load_temp_course_role(context_course $coursecontext, $roleid) {
bbfdff34 1181 global $USER, $SITE;
5a4e7398 1182
e922fe23
PS
1183 if (empty($roleid)) {
1184 debugging('invalid role specified in load_temp_course_role()');
1185 return;
1186 }
343effbe 1187
bbfdff34
PS
1188 if ($coursecontext->instanceid == $SITE->id) {
1189 debugging('Can not use temp roles on the frontpage');
1190 return;
1191 }
1192
e922fe23
PS
1193 if (!isset($USER->access)) {
1194 load_all_capabilities();
f33e1ed4 1195 }
343effbe 1196
e922fe23 1197 $coursecontext->reload_if_dirty();
343effbe 1198
e922fe23
PS
1199 if (isset($USER->access['ra'][$coursecontext->path][$roleid])) {
1200 return;
343effbe 1201 }
1202
e922fe23
PS
1203 // load course stuff first
1204 load_course_context($USER->id, $coursecontext, $USER->access);
1205
1206 $USER->access['ra'][$coursecontext->path][(int)$roleid] = (int)$roleid;
1207
1208 load_role_access_by_context($roleid, $coursecontext, $USER->access);
343effbe 1209}
1210
efe12f6c 1211/**
e922fe23 1212 * Removes any extra guest roles from current USER->access array.
99ddfdf4 1213 * @since 2.2
e922fe23
PS
1214 *
1215 * @param context_course $coursecontext
1216 * @return void
64026e8c 1217 */
e922fe23 1218function remove_temp_course_roles(context_course $coursecontext) {
bbfdff34
PS
1219 global $DB, $USER, $SITE;
1220
1221 if ($coursecontext->instanceid == $SITE->id) {
1222 debugging('Can not use temp roles on the frontpage');
1223 return;
1224 }
e922fe23
PS
1225
1226 if (empty($USER->access['ra'][$coursecontext->path])) {
1227 //no roles here, weird
1228 return;
1229 }
1230
df997f84
PS
1231 $sql = "SELECT DISTINCT ra.roleid AS id
1232 FROM {role_assignments} ra
1233 WHERE ra.contextid = :contextid AND ra.userid = :userid";
e922fe23 1234 $ras = $DB->get_records_sql($sql, array('contextid'=>$coursecontext->id, 'userid'=>$USER->id));
e4ec4e41 1235
e922fe23
PS
1236 $USER->access['ra'][$coursecontext->path] = array();
1237 foreach($ras as $r) {
1238 $USER->access['ra'][$coursecontext->path][(int)$r->id] = (int)$r->id;
0831484c 1239 }
64026e8c 1240}
1241
3562486b 1242/**
4f0c2d00 1243 * Returns array of all role archetypes.
cc3edaa4 1244 *
46808d7c 1245 * @return array
3562486b 1246 */
4f0c2d00 1247function get_role_archetypes() {
3562486b 1248 return array(
4f0c2d00
PS
1249 'manager' => 'manager',
1250 'coursecreator' => 'coursecreator',
1251 'editingteacher' => 'editingteacher',
1252 'teacher' => 'teacher',
1253 'student' => 'student',
1254 'guest' => 'guest',
1255 'user' => 'user',
1256 'frontpage' => 'frontpage'
3562486b 1257 );
1258}
1259
bbbf2d40 1260/**
4f65e0fb 1261 * Assign the defaults found in this capability definition to roles that have
bbbf2d40 1262 * the corresponding legacy capabilities assigned to them.
cc3edaa4 1263 *
46808d7c 1264 * @param string $capability
1265 * @param array $legacyperms an array in the format (example):
bbbf2d40 1266 * 'guest' => CAP_PREVENT,
1267 * 'student' => CAP_ALLOW,
1268 * 'teacher' => CAP_ALLOW,
1269 * 'editingteacher' => CAP_ALLOW,
1270 * 'coursecreator' => CAP_ALLOW,
4f0c2d00 1271 * 'manager' => CAP_ALLOW
46808d7c 1272 * @return boolean success or failure.
bbbf2d40 1273 */
1274function assign_legacy_capabilities($capability, $legacyperms) {
eef868d1 1275
4f0c2d00 1276 $archetypes = get_role_archetypes();
3562486b 1277
bbbf2d40 1278 foreach ($legacyperms as $type => $perm) {
eef868d1 1279
e922fe23 1280 $systemcontext = context_system::instance();
4f0c2d00
PS
1281 if ($type === 'admin') {
1282 debugging('Legacy type admin in access.php was renamed to manager, please update the code.');
1283 $type = 'manager';
1284 }
eef868d1 1285
4f0c2d00 1286 if (!array_key_exists($type, $archetypes)) {
e49ef64a 1287 print_error('invalidlegacy', '', '', $type);
3562486b 1288 }
eef868d1 1289
4f0c2d00 1290 if ($roles = get_archetype_roles($type)) {
2e85fffe 1291 foreach ($roles as $role) {
1292 // Assign a site level capability.
1293 if (!assign_capability($capability, $perm, $role->id, $systemcontext->id)) {
1294 return false;
1295 }
bbbf2d40 1296 }
1297 }
1298 }
1299 return true;
1300}
1301
faf75fe7 1302/**
e922fe23
PS
1303 * Verify capability risks.
1304 *
ed149942
PS
1305 * @param object $capability a capability - a row from the capabilities table.
1306 * @return boolean whether this capability is safe - that is, whether people with the
faf75fe7 1307 * safeoverrides capability should be allowed to change it.
1308 */
1309function is_safe_capability($capability) {
4659454a 1310 return !((RISK_DATALOSS | RISK_MANAGETRUST | RISK_CONFIG | RISK_XSS | RISK_PERSONAL) & $capability->riskbitmask);
faf75fe7 1311}
cee0901c 1312
bbbf2d40 1313/**
e922fe23 1314 * Get the local override (if any) for a given capability in a role in a context
a0760047 1315 *
e922fe23
PS
1316 * @param int $roleid
1317 * @param int $contextid
1318 * @param string $capability
1319 * @return stdClass local capability override
bbbf2d40 1320 */
e922fe23
PS
1321function get_local_override($roleid, $contextid, $capability) {
1322 global $DB;
1323 return $DB->get_record('role_capabilities', array('roleid'=>$roleid, 'capability'=>$capability, 'contextid'=>$contextid));
1324}
e40413be 1325
e922fe23
PS
1326/**
1327 * Returns context instance plus related course and cm instances
1328 *
1329 * @param int $contextid
1330 * @return array of ($context, $course, $cm)
1331 */
1332function get_context_info_array($contextid) {
1333 global $DB;
e40413be 1334
e922fe23
PS
1335 $context = context::instance_by_id($contextid, MUST_EXIST);
1336 $course = null;
1337 $cm = null;
e40413be 1338
e922fe23
PS
1339 if ($context->contextlevel == CONTEXT_COURSE) {
1340 $course = $DB->get_record('course', array('id'=>$context->instanceid), '*', MUST_EXIST);
e40413be 1341
e922fe23
PS
1342 } else if ($context->contextlevel == CONTEXT_MODULE) {
1343 $cm = get_coursemodule_from_id('', $context->instanceid, 0, false, MUST_EXIST);
1344 $course = $DB->get_record('course', array('id'=>$cm->course), '*', MUST_EXIST);
7d0c81b3 1345
e922fe23
PS
1346 } else if ($context->contextlevel == CONTEXT_BLOCK) {
1347 $parent = $context->get_parent_context();
f689028c 1348
e922fe23
PS
1349 if ($parent->contextlevel == CONTEXT_COURSE) {
1350 $course = $DB->get_record('course', array('id'=>$parent->instanceid), '*', MUST_EXIST);
1351 } else if ($parent->contextlevel == CONTEXT_MODULE) {
1352 $cm = get_coursemodule_from_id('', $parent->instanceid, 0, false, MUST_EXIST);
1353 $course = $DB->get_record('course', array('id'=>$cm->course), '*', MUST_EXIST);
1354 }
bbbf2d40 1355 }
4f0c2d00 1356
e922fe23 1357 return array($context, $course, $cm);
bbbf2d40 1358}
1359
efe12f6c 1360/**
e922fe23 1361 * Function that creates a role
46808d7c 1362 *
e922fe23
PS
1363 * @param string $name role name
1364 * @param string $shortname role short name
1365 * @param string $description role description
1366 * @param string $archetype
1367 * @return int id or dml_exception
8ba412da 1368 */
e922fe23
PS
1369function create_role($name, $shortname, $description, $archetype = '') {
1370 global $DB;
7d0c81b3 1371
e922fe23
PS
1372 if (strpos($archetype, 'moodle/legacy:') !== false) {
1373 throw new coding_exception('Use new role archetype parameter in create_role() instead of old legacy capabilities.');
8ba412da 1374 }
7d0c81b3 1375
e922fe23
PS
1376 // verify role archetype actually exists
1377 $archetypes = get_role_archetypes();
1378 if (empty($archetypes[$archetype])) {
1379 $archetype = '';
7d0c81b3 1380 }
1381
e922fe23
PS
1382 // Insert the role record.
1383 $role = new stdClass();
1384 $role->name = $name;
1385 $role->shortname = $shortname;
1386 $role->description = $description;
1387 $role->archetype = $archetype;
1388
1389 //find free sortorder number
1390 $role->sortorder = $DB->get_field('role', 'MAX(sortorder) + 1', array());
1391 if (empty($role->sortorder)) {
1392 $role->sortorder = 1;
7d0c81b3 1393 }
e922fe23 1394 $id = $DB->insert_record('role', $role);
7d0c81b3 1395
e922fe23 1396 return $id;
8ba412da 1397}
b51ece5b 1398
9991d157 1399/**
e922fe23 1400 * Function that deletes a role and cleanups up after it
cc3edaa4 1401 *
e922fe23
PS
1402 * @param int $roleid id of role to delete
1403 * @return bool always true
9991d157 1404 */
e922fe23
PS
1405function delete_role($roleid) {
1406 global $DB;
b51ece5b 1407
e922fe23
PS
1408 // first unssign all users
1409 role_unassign_all(array('roleid'=>$roleid));
2ac56258 1410
e922fe23
PS
1411 // cleanup all references to this role, ignore errors
1412 $DB->delete_records('role_capabilities', array('roleid'=>$roleid));
1413 $DB->delete_records('role_allow_assign', array('roleid'=>$roleid));
1414 $DB->delete_records('role_allow_assign', array('allowassign'=>$roleid));
1415 $DB->delete_records('role_allow_override', array('roleid'=>$roleid));
1416 $DB->delete_records('role_allow_override', array('allowoverride'=>$roleid));
1417 $DB->delete_records('role_names', array('roleid'=>$roleid));
1418 $DB->delete_records('role_context_levels', array('roleid'=>$roleid));
a05bcfba 1419
e922fe23
PS
1420 // finally delete the role itself
1421 // get this before the name is gone for logging
1422 $rolename = $DB->get_field('role', 'name', array('id'=>$roleid));
582bae08 1423
e922fe23 1424 $DB->delete_records('role', array('id'=>$roleid));
582bae08 1425
e922fe23 1426 add_to_log(SITEID, 'role', 'delete', 'admin/roles/action=delete&roleid='.$roleid, $rolename, '');
196f1a25
PS
1427
1428 return true;
9991d157 1429}
1430
9a81a606 1431/**
e922fe23 1432 * Function to write context specific overrides, or default capabilities.
cc3edaa4 1433 *
e922fe23
PS
1434 * NOTE: use $context->mark_dirty() after this
1435 *
1436 * @param string $capability string name
1437 * @param int $permission CAP_ constants
1438 * @param int $roleid role id
1439 * @param int|context $contextid context id
1440 * @param bool $overwrite
1441 * @return bool always true or exception
9a81a606 1442 */
e922fe23
PS
1443function assign_capability($capability, $permission, $roleid, $contextid, $overwrite = false) {
1444 global $USER, $DB;
9a81a606 1445
e922fe23
PS
1446 if ($contextid instanceof context) {
1447 $context = $contextid;
1448 } else {
1449 $context = context::instance_by_id($contextid);
9a81a606 1450 }
1451
e922fe23
PS
1452 if (empty($permission) || $permission == CAP_INHERIT) { // if permission is not set
1453 unassign_capability($capability, $roleid, $context->id);
1454 return true;
9a81a606 1455 }
1456
e922fe23 1457 $existing = $DB->get_record('role_capabilities', array('contextid'=>$context->id, 'roleid'=>$roleid, 'capability'=>$capability));
9a81a606 1458
e922fe23
PS
1459 if ($existing and !$overwrite) { // We want to keep whatever is there already
1460 return true;
9a81a606 1461 }
1462
e922fe23
PS
1463 $cap = new stdClass();
1464 $cap->contextid = $context->id;
1465 $cap->roleid = $roleid;
1466 $cap->capability = $capability;
1467 $cap->permission = $permission;
1468 $cap->timemodified = time();
1469 $cap->modifierid = empty($USER->id) ? 0 : $USER->id;
e92c286c 1470
e922fe23
PS
1471 if ($existing) {
1472 $cap->id = $existing->id;
1473 $DB->update_record('role_capabilities', $cap);
1474 } else {
1475 if ($DB->record_exists('context', array('id'=>$context->id))) {
1476 $DB->insert_record('role_capabilities', $cap);
1477 }
9a81a606 1478 }
e922fe23 1479 return true;
9a81a606 1480}
1481
17b0efae 1482/**
e922fe23 1483 * Unassign a capability from a role.
17b0efae 1484 *
e922fe23
PS
1485 * NOTE: use $context->mark_dirty() after this
1486 *
1487 * @param string $capability the name of the capability
1488 * @param int $roleid the role id
1489 * @param int|context $contextid null means all contexts
1490 * @return boolean true or exception
17b0efae 1491 */
e922fe23 1492function unassign_capability($capability, $roleid, $contextid = null) {
5a4e7398 1493 global $DB;
17b0efae 1494
e922fe23
PS
1495 if (!empty($contextid)) {
1496 if ($contextid instanceof context) {
1497 $context = $contextid;
1498 } else {
1499 $context = context::instance_by_id($contextid);
1500 }
1501 // delete from context rel, if this is the last override in this context
1502 $DB->delete_records('role_capabilities', array('capability'=>$capability, 'roleid'=>$roleid, 'contextid'=>$context->id));
1503 } else {
1504 $DB->delete_records('role_capabilities', array('capability'=>$capability, 'roleid'=>$roleid));
17b0efae 1505 }
1506 return true;
1507}
1508
00653161 1509/**
e922fe23 1510 * Get the roles that have a given capability assigned to it
00653161 1511 *
e922fe23
PS
1512 * This function does not resolve the actual permission of the capability.
1513 * It just checks for permissions and overrides.
1514 * Use get_roles_with_cap_in_context() if resolution is required.
1515 *
1516 * @param string $capability - capability name (string)
1517 * @param string $permission - optional, the permission defined for this capability
1518 * either CAP_ALLOW, CAP_PREVENT or CAP_PROHIBIT. Defaults to null which means any.
1519 * @param stdClass $context, null means any
1520 * @return array of role records
00653161 1521 */
e922fe23
PS
1522function get_roles_with_capability($capability, $permission = null, $context = null) {
1523 global $DB;
00653161 1524
e922fe23
PS
1525 if ($context) {
1526 $contexts = $context->get_parent_context_ids(true);
1527 list($insql, $params) = $DB->get_in_or_equal($contexts, SQL_PARAMS_NAMED, 'ctx');
1528 $contextsql = "AND rc.contextid $insql";
1529 } else {
1530 $params = array();
1531 $contextsql = '';
00653161 1532 }
1533
e922fe23
PS
1534 if ($permission) {
1535 $permissionsql = " AND rc.permission = :permission";
1536 $params['permission'] = $permission;
1537 } else {
1538 $permissionsql = '';
00653161 1539 }
e922fe23
PS
1540
1541 $sql = "SELECT r.*
1542 FROM {role} r
1543 WHERE r.id IN (SELECT rc.roleid
1544 FROM {role_capabilities} rc
1545 WHERE rc.capability = :capname
1546 $contextsql
1547 $permissionsql)";
1548 $params['capname'] = $capability;
1549
1550
1551 return $DB->get_records_sql($sql, $params);
00653161 1552}
1553
bbbf2d40 1554/**
e922fe23 1555 * This function makes a role-assignment (a role for a user in a particular context)
46808d7c 1556 *
e922fe23
PS
1557 * @param int $roleid the role of the id
1558 * @param int $userid userid
1559 * @param int|context $contextid id of the context
1560 * @param string $component example 'enrol_ldap', defaults to '' which means manual assignment,
1561 * @param int $itemid id of enrolment/auth plugin
1562 * @param string $timemodified defaults to current time
1563 * @return int new/existing id of the assignment
bbbf2d40 1564 */
e922fe23
PS
1565function role_assign($roleid, $userid, $contextid, $component = '', $itemid = 0, $timemodified = '') {
1566 global $USER, $DB;
d9a35e12 1567
e922fe23
PS
1568 // first of all detect if somebody is using old style parameters
1569 if ($contextid === 0 or is_numeric($component)) {
1570 throw new coding_exception('Invalid call to role_assign(), code needs to be updated to use new order of parameters');
8ba412da 1571 }
1572
e922fe23
PS
1573 // now validate all parameters
1574 if (empty($roleid)) {
1575 throw new coding_exception('Invalid call to role_assign(), roleid can not be empty');
a36a3a3f 1576 }
1577
e922fe23
PS
1578 if (empty($userid)) {
1579 throw new coding_exception('Invalid call to role_assign(), userid can not be empty');
1580 }
d0e538ba 1581
e922fe23
PS
1582 if ($itemid) {
1583 if (strpos($component, '_') === false) {
1584 throw new coding_exception('Invalid call to role_assign(), component must start with plugin type such as"enrol_" when itemid specified', 'component:'.$component);
65bcf17b 1585 }
e922fe23
PS
1586 } else {
1587 $itemid = 0;
1588 if ($component !== '' and strpos($component, '_') === false) {
1589 throw new coding_exception('Invalid call to role_assign(), invalid component string', 'component:'.$component);
65bcf17b 1590 }
e922fe23 1591 }
65bcf17b 1592
e922fe23
PS
1593 if (!$DB->record_exists('user', array('id'=>$userid, 'deleted'=>0))) {
1594 throw new coding_exception('User ID does not exist or is deleted!', 'userid:'.$userid);
1595 }
65bcf17b 1596
e922fe23
PS
1597 if ($contextid instanceof context) {
1598 $context = $contextid;
1599 } else {
1600 $context = context::instance_by_id($contextid, MUST_EXIST);
e5605780 1601 }
1602
e922fe23
PS
1603 if (!$timemodified) {
1604 $timemodified = time();
1605 }
65bcf17b 1606
e922fe23
PS
1607/// Check for existing entry
1608 $ras = $DB->get_records('role_assignments', array('roleid'=>$roleid, 'contextid'=>$context->id, 'userid'=>$userid, 'component'=>$component, 'itemid'=>$itemid), 'id');
65bcf17b 1609
e922fe23
PS
1610 if ($ras) {
1611 // role already assigned - this should not happen
1612 if (count($ras) > 1) {
1613 // very weird - remove all duplicates!
1614 $ra = array_shift($ras);
1615 foreach ($ras as $r) {
1616 $DB->delete_records('role_assignments', array('id'=>$r->id));
1617 }
1618 } else {
1619 $ra = reset($ras);
65bcf17b 1620 }
e5605780 1621
e922fe23
PS
1622 // actually there is no need to update, reset anything or trigger any event, so just return
1623 return $ra->id;
1624 }
5a4e7398 1625
e922fe23
PS
1626 // Create a new entry
1627 $ra = new stdClass();
1628 $ra->roleid = $roleid;
1629 $ra->contextid = $context->id;
1630 $ra->userid = $userid;
1631 $ra->component = $component;
1632 $ra->itemid = $itemid;
1633 $ra->timemodified = $timemodified;
1634 $ra->modifierid = empty($USER->id) ? 0 : $USER->id;
65bcf17b 1635
e922fe23 1636 $ra->id = $DB->insert_record('role_assignments', $ra);
65bcf17b 1637
e922fe23
PS
1638 // mark context as dirty - again expensive, but needed
1639 $context->mark_dirty();
65bcf17b 1640
e922fe23
PS
1641 if (!empty($USER->id) && $USER->id == $userid) {
1642 // If the user is the current user, then do full reload of capabilities too.
1643 reload_all_capabilities();
ccfc5ecc 1644 }
0468976c 1645
e922fe23 1646 events_trigger('role_assigned', $ra);
bbbf2d40 1647
e922fe23
PS
1648 return $ra->id;
1649}
cee0901c 1650
340ea4e8 1651/**
e922fe23 1652 * Removes one role assignment
cc3edaa4 1653 *
e922fe23
PS
1654 * @param int $roleid
1655 * @param int $userid
1656 * @param int|context $contextid
1657 * @param string $component
1658 * @param int $itemid
1659 * @return void
340ea4e8 1660 */
e922fe23
PS
1661function role_unassign($roleid, $userid, $contextid, $component = '', $itemid = 0) {
1662 // first make sure the params make sense
1663 if ($roleid == 0 or $userid == 0 or $contextid == 0) {
1664 throw new coding_exception('Invalid call to role_unassign(), please use role_unassign_all() when removing multiple role assignments');
340ea4e8 1665 }
1666
e922fe23
PS
1667 if ($itemid) {
1668 if (strpos($component, '_') === false) {
1669 throw new coding_exception('Invalid call to role_assign(), component must start with plugin type such as "enrol_" when itemid specified', 'component:'.$component);
1670 }
1671 } else {
1672 $itemid = 0;
1673 if ($component !== '' and strpos($component, '_') === false) {
1674 throw new coding_exception('Invalid call to role_assign(), invalid component string', 'component:'.$component);
1675 }
340ea4e8 1676 }
1677
e922fe23 1678 role_unassign_all(array('roleid'=>$roleid, 'userid'=>$userid, 'contextid'=>$contextid, 'component'=>$component, 'itemid'=>$itemid), false, false);
340ea4e8 1679}
1680
8737be58 1681/**
e922fe23
PS
1682 * Removes multiple role assignments, parameters may contain:
1683 * 'roleid', 'userid', 'contextid', 'component', 'enrolid'.
cc3edaa4 1684 *
e922fe23
PS
1685 * @param array $params role assignment parameters
1686 * @param bool $subcontexts unassign in subcontexts too
1687 * @param bool $includemanual include manual role assignments too
1688 * @return void
01a2ce80 1689 */
e922fe23
PS
1690function role_unassign_all(array $params, $subcontexts = false, $includemanual = false) {
1691 global $USER, $CFG, $DB;
01a2ce80 1692
e922fe23
PS
1693 if (!$params) {
1694 throw new coding_exception('Missing parameters in role_unsassign_all() call');
1695 }
01a2ce80 1696
e922fe23
PS
1697 $allowed = array('roleid', 'userid', 'contextid', 'component', 'itemid');
1698 foreach ($params as $key=>$value) {
1699 if (!in_array($key, $allowed)) {
1700 throw new coding_exception('Unknown role_unsassign_all() parameter key', 'key:'.$key);
01a2ce80
PS
1701 }
1702 }
1703
e922fe23
PS
1704 if (isset($params['component']) and $params['component'] !== '' and strpos($params['component'], '_') === false) {
1705 throw new coding_exception('Invalid component paramter in role_unsassign_all() call', 'component:'.$params['component']);
28765cfc 1706 }
e922fe23
PS
1707
1708 if ($includemanual) {
1709 if (!isset($params['component']) or $params['component'] === '') {
1710 throw new coding_exception('include manual parameter requires component parameter in role_unsassign_all() call');
1711 }
35716b86
PS
1712 }
1713
e922fe23
PS
1714 if ($subcontexts) {
1715 if (empty($params['contextid'])) {
1716 throw new coding_exception('subcontexts paramtere requires component parameter in role_unsassign_all() call');
1717 }
35716b86
PS
1718 }
1719
e922fe23
PS
1720 $ras = $DB->get_records('role_assignments', $params);
1721 foreach($ras as $ra) {
1722 $DB->delete_records('role_assignments', array('id'=>$ra->id));
1723 if ($context = context::instance_by_id($ra->contextid, IGNORE_MISSING)) {
1724 // this is a bit expensive but necessary
1725 $context->mark_dirty();
1726 /// If the user is the current user, then do full reload of capabilities too.
1727 if (!empty($USER->id) && $USER->id == $ra->userid) {
1728 reload_all_capabilities();
1729 }
1730 }
1731 events_trigger('role_unassigned', $ra);
35716b86 1732 }
e922fe23
PS
1733 unset($ras);
1734
1735 // process subcontexts
1736 if ($subcontexts and $context = context::instance_by_id($params['contextid'], IGNORE_MISSING)) {
1737 if ($params['contextid'] instanceof context) {
1738 $context = $params['contextid'];
1739 } else {
1740 $context = context::instance_by_id($params['contextid'], IGNORE_MISSING);
1741 }
35716b86 1742
e922fe23
PS
1743 if ($context) {
1744 $contexts = $context->get_child_contexts();
1745 $mparams = $params;
1746 foreach($contexts as $context) {
1747 $mparams['contextid'] = $context->id;
1748 $ras = $DB->get_records('role_assignments', $mparams);
1749 foreach($ras as $ra) {
1750 $DB->delete_records('role_assignments', array('id'=>$ra->id));
1751 // this is a bit expensive but necessary
1752 $context->mark_dirty();
1753 /// If the user is the current user, then do full reload of capabilities too.
1754 if (!empty($USER->id) && $USER->id == $ra->userid) {
1755 reload_all_capabilities();
1756 }
1757 events_trigger('role_unassigned', $ra);
1758 }
1759 }
1760 }
35716b86
PS
1761 }
1762
e922fe23
PS
1763 // do this once more for all manual role assignments
1764 if ($includemanual) {
1765 $params['component'] = '';
1766 role_unassign_all($params, $subcontexts, false);
1767 }
35716b86
PS
1768}
1769
e922fe23
PS
1770/**
1771 * Determines if a user is currently logged in
1772 *
1773 * @return bool
1774 */
1775function isloggedin() {
1776 global $USER;
bbbf2d40 1777
e922fe23
PS
1778 return (!empty($USER->id));
1779}
bbbf2d40 1780
cee0901c 1781/**
e922fe23 1782 * Determines if a user is logged in as real guest user with username 'guest'.
cc3edaa4 1783 *
e922fe23
PS
1784 * @param int|object $user mixed user object or id, $USER if not specified
1785 * @return bool true if user is the real guest user, false if not logged in or other user
bbbf2d40 1786 */
e922fe23
PS
1787function isguestuser($user = null) {
1788 global $USER, $DB, $CFG;
eef868d1 1789
e922fe23
PS
1790 // make sure we have the user id cached in config table, because we are going to use it a lot
1791 if (empty($CFG->siteguest)) {
1792 if (!$guestid = $DB->get_field('user', 'id', array('username'=>'guest', 'mnethostid'=>$CFG->mnet_localhost_id))) {
1793 // guest does not exist yet, weird
1794 return false;
1795 }
1796 set_config('siteguest', $guestid);
4f0c2d00 1797 }
e922fe23
PS
1798 if ($user === null) {
1799 $user = $USER;
4f0c2d00
PS
1800 }
1801
e922fe23
PS
1802 if ($user === null) {
1803 // happens when setting the $USER
1804 return false;
31f26796 1805
e922fe23
PS
1806 } else if (is_numeric($user)) {
1807 return ($CFG->siteguest == $user);
eef868d1 1808
e922fe23
PS
1809 } else if (is_object($user)) {
1810 if (empty($user->id)) {
1811 return false; // not logged in means is not be guest
1812 } else {
1813 return ($CFG->siteguest == $user->id);
1814 }
b5959f30 1815
e922fe23
PS
1816 } else {
1817 throw new coding_exception('Invalid user parameter supplied for isguestuser() function!');
1818 }
bbbf2d40 1819}
1820
8420bee9 1821/**
e922fe23 1822 * Does user have a (temporary or real) guest access to course?
cc3edaa4 1823 *
e922fe23
PS
1824 * @param context $context
1825 * @param stdClass|int $user
1826 * @return bool
8420bee9 1827 */
e922fe23
PS
1828function is_guest(context $context, $user = null) {
1829 global $USER;
c421ad4b 1830
e922fe23
PS
1831 // first find the course context
1832 $coursecontext = $context->get_course_context();
c421ad4b 1833
e922fe23
PS
1834 // make sure there is a real user specified
1835 if ($user === null) {
1836 $userid = isset($USER->id) ? $USER->id : 0;
1837 } else {
1838 $userid = is_object($user) ? $user->id : $user;
1839 }
60ace1e1 1840
e922fe23
PS
1841 if (isguestuser($userid)) {
1842 // can not inspect or be enrolled
1843 return true;
1844 }
5a4e7398 1845
e922fe23
PS
1846 if (has_capability('moodle/course:view', $coursecontext, $user)) {
1847 // viewing users appear out of nowhere, they are neither guests nor participants
1848 return false;
1849 }
5a4e7398 1850
e922fe23
PS
1851 // consider only real active enrolments here
1852 if (is_enrolled($coursecontext, $user, '', true)) {
1853 return false;
1854 }
8420bee9 1855
4f0c2d00 1856 return true;
8420bee9 1857}
1858
bbbf2d40 1859/**
e922fe23
PS
1860 * Returns true if the user has moodle/course:view capability in the course,
1861 * this is intended for admins, managers (aka small admins), inspectors, etc.
46808d7c 1862 *
e922fe23
PS
1863 * @param context $context
1864 * @param int|stdClass $user, if null $USER is used
1865 * @param string $withcapability extra capability name
1866 * @return bool
bbbf2d40 1867 */
e922fe23
PS
1868function is_viewing(context $context, $user = null, $withcapability = '') {
1869 // first find the course context
1870 $coursecontext = $context->get_course_context();
eef868d1 1871
e922fe23
PS
1872 if (isguestuser($user)) {
1873 // can not inspect
1874 return false;
98882637 1875 }
eef868d1 1876
e922fe23
PS
1877 if (!has_capability('moodle/course:view', $coursecontext, $user)) {
1878 // admins are allowed to inspect courses
1879 return false;
e7876c1e 1880 }
1881
e922fe23
PS
1882 if ($withcapability and !has_capability($withcapability, $context, $user)) {
1883 // site admins always have the capability, but the enrolment above blocks
1884 return false;
e7876c1e 1885 }
e922fe23 1886
4f0c2d00 1887 return true;
bbbf2d40 1888}
1889
bbbf2d40 1890/**
e922fe23
PS
1891 * Returns true if user is enrolled (is participating) in course
1892 * this is intended for students and teachers.
117bd748 1893 *
bbfdff34
PS
1894 * Since 2.2 the result for active enrolments and current user are cached.
1895 *
e922fe23
PS
1896 * @param context $context
1897 * @param int|stdClass $user, if null $USER is used, otherwise user object or id expected
1898 * @param string $withcapability extra capability name
1899 * @param bool $onlyactive consider only active enrolments in enabled plugins and time restrictions
1900 * @return bool
bbbf2d40 1901 */
e922fe23
PS
1902function is_enrolled(context $context, $user = null, $withcapability = '', $onlyactive = false) {
1903 global $USER, $DB;
eef868d1 1904
e922fe23
PS
1905 // first find the course context
1906 $coursecontext = $context->get_course_context();
1907
1908 // make sure there is a real user specified
1909 if ($user === null) {
1910 $userid = isset($USER->id) ? $USER->id : 0;
98882637 1911 } else {
e922fe23 1912 $userid = is_object($user) ? $user->id : $user;
98882637 1913 }
5a4e7398 1914
e922fe23
PS
1915 if (empty($userid)) {
1916 // not-logged-in!
1917 return false;
1918 } else if (isguestuser($userid)) {
1919 // guest account can not be enrolled anywhere
1920 return false;
448aad7f
PS
1921 }
1922
e922fe23
PS
1923 if ($coursecontext->instanceid == SITEID) {
1924 // everybody participates on frontpage
ec7a8b79 1925 } else {
bbfdff34
PS
1926 // try cached info first - the enrolled flag is set only when active enrolment present
1927 if ($USER->id == $userid) {
1928 $coursecontext->reload_if_dirty();
1929 if (isset($USER->enrol['enrolled'][$coursecontext->instanceid])) {
1930 if ($USER->enrol['enrolled'][$coursecontext->instanceid] > time()) {
1931 return true;
e922fe23 1932 }
e922fe23 1933 }
bbfdff34
PS
1934 }
1935
1936 if ($onlyactive) {
1937 // look for active enrolments only
1938 $until = enrol_get_enrolment_end($coursecontext->instanceid, $userid);
1939
1940 if ($until === false) {
e922fe23
PS
1941 return false;
1942 }
eef868d1 1943
bbfdff34
PS
1944 if ($USER->id == $userid) {
1945 if ($until == 0) {
1946 $until = ENROL_MAX_TIMESTAMP;
1947 }
1948 $USER->enrol['enrolled'][$coursecontext->instanceid] = $until;
1949 if (isset($USER->enrol['tempguest'][$coursecontext->instanceid])) {
1950 unset($USER->enrol['tempguest'][$coursecontext->instanceid]);
1951 remove_temp_course_roles($coursecontext);
1952 }
1953 }
1954
e922fe23
PS
1955 } else {
1956 // any enrolment is good for us here, even outdated, disabled or inactive
1957 $sql = "SELECT 'x'
1958 FROM {user_enrolments} ue
1959 JOIN {enrol} e ON (e.id = ue.enrolid AND e.courseid = :courseid)
1960 JOIN {user} u ON u.id = ue.userid
1961 WHERE ue.userid = :userid AND u.deleted = 0";
1962 $params = array('userid'=>$userid, 'courseid'=>$coursecontext->instanceid);
1963 if (!$DB->record_exists_sql($sql, $params)) {
1964 return false;
1965 }
1966 }
1967 }
bbbf2d40 1968
e922fe23
PS
1969 if ($withcapability and !has_capability($withcapability, $context, $userid)) {
1970 return false;
1971 }
f33e1ed4 1972
e922fe23 1973 return true;
bbbf2d40 1974}
1975
bbbf2d40 1976/**
e922fe23 1977 * Returns true if the user is able to access the course.
117bd748 1978 *
e922fe23
PS
1979 * This function is in no way, shape, or form a substitute for require_login.
1980 * It should only be used in circumstances where it is not possible to call require_login
1981 * such as the navigation.
1982 *
1983 * This function checks many of the methods of access to a course such as the view
1984 * capability, enrollments, and guest access. It also makes use of the cache
1985 * generated by require_login for guest access.
1986 *
1987 * The flags within the $USER object that are used here should NEVER be used outside
1988 * of this function can_access_course and require_login. Doing so WILL break future
1989 * versions.
1990 *
1344b0ca
PS
1991 * @param stdClass $course record
1992 * @param stdClass|int|null $user user record or id, current user if null
e922fe23
PS
1993 * @param string $withcapability Check for this capability as well.
1994 * @param bool $onlyactive consider only active enrolments in enabled plugins and time restrictions
e922fe23
PS
1995 * @return boolean Returns true if the user is able to access the course
1996 */
1344b0ca 1997function can_access_course(stdClass $course, $user = null, $withcapability = '', $onlyactive = false) {
e922fe23 1998 global $DB, $USER;
eef868d1 1999
1344b0ca
PS
2000 // this function originally accepted $coursecontext parameter
2001 if ($course instanceof context) {
2002 if ($course instanceof context_course) {
2003 debugging('deprecated context parameter, please use $course record');
2004 $coursecontext = $course;
2005 $course = $DB->get_record('course', array('id'=>$coursecontext->instanceid));
2006 } else {
2007 debugging('Invalid context parameter, please use $course record');
2008 return false;
2009 }
2010 } else {
2011 $coursecontext = context_course::instance($course->id);
2012 }
2013
2014 if (!isset($USER->id)) {
2015 // should never happen
2016 $USER->id = 0;
2017 }
2018
2019 // make sure there is a user specified
2020 if ($user === null) {
2021 $userid = $USER->id;
2022 } else {
2023 $userid = is_object($user) ? $user->id : $user;
2024 }
2025 unset($user);
bbbf2d40 2026
1344b0ca
PS
2027 if ($withcapability and !has_capability($withcapability, $coursecontext, $userid)) {
2028 return false;
2029 }
2030
2031 if ($userid == $USER->id) {
2032 if (!empty($USER->access['rsw'][$coursecontext->path])) {
2033 // the fact that somebody switched role means they can access the course no matter to what role they switched
2034 return true;
2035 }
2036 }
2037
0f14c827 2038 if (!$course->visible and !has_capability('moodle/course:viewhiddencourses', $coursecontext, $userid)) {
1344b0ca
PS
2039 return false;
2040 }
2041
2042 if (is_viewing($coursecontext, $userid)) {
e922fe23 2043 return true;
bbbf2d40 2044 }
2045
1344b0ca
PS
2046 if ($userid != $USER->id) {
2047 // for performance reasons we do not verify temporary guest access for other users, sorry...
2048 return is_enrolled($coursecontext, $userid, '', $onlyactive);
2049 }
2050
0f14c827
PS
2051 // === from here we deal only with $USER ===
2052
bbfdff34
PS
2053 $coursecontext->reload_if_dirty();
2054
1344b0ca 2055 if (isset($USER->enrol['enrolled'][$course->id])) {
bbfdff34 2056 if ($USER->enrol['enrolled'][$course->id] > time()) {
1344b0ca
PS
2057 return true;
2058 }
2059 }
2060 if (isset($USER->enrol['tempguest'][$course->id])) {
bbfdff34 2061 if ($USER->enrol['tempguest'][$course->id] > time()) {
1344b0ca
PS
2062 return true;
2063 }
2064 }
7700027f 2065
bbfdff34 2066 if (is_enrolled($coursecontext, $USER, '', $onlyactive)) {
1344b0ca 2067 return true;
96608a55 2068 }
c421ad4b 2069
1344b0ca
PS
2070 // if not enrolled try to gain temporary guest access
2071 $instances = $DB->get_records('enrol', array('courseid'=>$course->id, 'status'=>ENROL_INSTANCE_ENABLED), 'sortorder, id ASC');
2072 $enrols = enrol_get_plugins(true);
2073 foreach($instances as $instance) {
2074 if (!isset($enrols[$instance->enrol])) {
2075 continue;
2076 }
bbfdff34 2077 // Get a duration for the guest access, a timestamp in the future, 0 (always) or false.
1344b0ca 2078 $until = $enrols[$instance->enrol]->try_guestaccess($instance);
bbfdff34 2079 if ($until !== false and $until > time()) {
1344b0ca
PS
2080 $USER->enrol['tempguest'][$course->id] = $until;
2081 return true;
e922fe23 2082 }
4e5f3064 2083 }
bbfdff34
PS
2084 if (isset($USER->enrol['tempguest'][$course->id])) {
2085 unset($USER->enrol['tempguest'][$course->id]);
2086 remove_temp_course_roles($coursecontext);
2087 }
1344b0ca
PS
2088
2089 return false;
bbbf2d40 2090}
2091
bbbf2d40 2092/**
e922fe23
PS
2093 * Returns array with sql code and parameters returning all ids
2094 * of users enrolled into course.
cc3edaa4 2095 *
e922fe23
PS
2096 * This function is using 'eu[0-9]+_' prefix for table names and parameters.
2097 *
2098 * @param context $context
2099 * @param string $withcapability
2100 * @param int $groupid 0 means ignore groups, any other value limits the result by group id
2101 * @param bool $onlyactive consider only active enrolments in enabled plugins and time restrictions
2102 * @return array list($sql, $params)
bbbf2d40 2103 */
e922fe23
PS
2104function get_enrolled_sql(context $context, $withcapability = '', $groupid = 0, $onlyactive = false) {
2105 global $DB, $CFG;
4f0c2d00 2106
e922fe23
PS
2107 // use unique prefix just in case somebody makes some SQL magic with the result
2108 static $i = 0;
2109 $i++;
2110 $prefix = 'eu'.$i.'_';
4f0c2d00 2111
e922fe23
PS
2112 // first find the course context
2113 $coursecontext = $context->get_course_context();
4f0c2d00 2114
e922fe23 2115 $isfrontpage = ($coursecontext->instanceid == SITEID);
4f0c2d00 2116
e922fe23
PS
2117 $joins = array();
2118 $wheres = array();
2119 $params = array();
4f0c2d00 2120
e922fe23 2121 list($contextids, $contextpaths) = get_context_info_list($context);
4f0c2d00 2122
e922fe23
PS
2123 // get all relevant capability info for all roles
2124 if ($withcapability) {
2125 list($incontexts, $cparams) = $DB->get_in_or_equal($contextids, SQL_PARAMS_NAMED, 'ctx');
2126 $cparams['cap'] = $withcapability;
4f0c2d00 2127
e922fe23
PS
2128 $defs = array();
2129 $sql = "SELECT rc.id, rc.roleid, rc.permission, ctx.path
2130 FROM {role_capabilities} rc
2131 JOIN {context} ctx on rc.contextid = ctx.id
2132 WHERE rc.contextid $incontexts AND rc.capability = :cap";
2133 $rcs = $DB->get_records_sql($sql, $cparams);
2134 foreach ($rcs as $rc) {
2135 $defs[$rc->path][$rc->roleid] = $rc->permission;
df997f84 2136 }
4f0c2d00 2137
e922fe23
PS
2138 $access = array();
2139 if (!empty($defs)) {
2140 foreach ($contextpaths as $path) {
2141 if (empty($defs[$path])) {
2142 continue;
2143 }
2144 foreach($defs[$path] as $roleid => $perm) {
2145 if ($perm == CAP_PROHIBIT) {
2146 $access[$roleid] = CAP_PROHIBIT;
2147 continue;
2148 }
2149 if (!isset($access[$roleid])) {
2150 $access[$roleid] = (int)$perm;
2151 }
2152 }
df997f84
PS
2153 }
2154 }
4f0c2d00 2155
e922fe23
PS
2156 unset($defs);
2157
2158 // make lists of roles that are needed and prohibited
2159 $needed = array(); // one of these is enough
2160 $prohibited = array(); // must not have any of these
2161 foreach ($access as $roleid => $perm) {
2162 if ($perm == CAP_PROHIBIT) {
2163 unset($needed[$roleid]);
2164 $prohibited[$roleid] = true;
2165 } else if ($perm == CAP_ALLOW and empty($prohibited[$roleid])) {
2166 $needed[$roleid] = true;
df997f84
PS
2167 }
2168 }
4f0c2d00 2169
e922fe23
PS
2170 $defaultuserroleid = isset($CFG->defaultuserroleid) ? $CFG->defaultuserroleid : 0;
2171 $defaultfrontpageroleid = isset($CFG->defaultfrontpageroleid) ? $CFG->defaultfrontpageroleid : 0;
4f0c2d00 2172
e922fe23 2173 $nobody = false;
df997f84 2174
e922fe23
PS
2175 if ($isfrontpage) {
2176 if (!empty($prohibited[$defaultuserroleid]) or !empty($prohibited[$defaultfrontpageroleid])) {
2177 $nobody = true;
2178 } else if (!empty($needed[$defaultuserroleid]) or !empty($needed[$defaultfrontpageroleid])) {
2179 // everybody not having prohibit has the capability
2180 $needed = array();
2181 } else if (empty($needed)) {
2182 $nobody = true;
2183 }
2184 } else {
2185 if (!empty($prohibited[$defaultuserroleid])) {
2186 $nobody = true;
2187 } else if (!empty($needed[$defaultuserroleid])) {
2188 // everybody not having prohibit has the capability
2189 $needed = array();
2190 } else if (empty($needed)) {
2191 $nobody = true;
2192 }
2193 }
4f0c2d00 2194
e922fe23
PS
2195 if ($nobody) {
2196 // nobody can match so return some SQL that does not return any results
2197 $wheres[] = "1 = 2";
4f0c2d00 2198
e922fe23 2199 } else {
4f0c2d00 2200
e922fe23
PS
2201 if ($needed) {
2202 $ctxids = implode(',', $contextids);
2203 $roleids = implode(',', array_keys($needed));
2204 $joins[] = "JOIN {role_assignments} {$prefix}ra3 ON ({$prefix}ra3.userid = {$prefix}u.id AND {$prefix}ra3.roleid IN ($roleids) AND {$prefix}ra3.contextid IN ($ctxids))";
2205 }
4f0c2d00 2206
e922fe23
PS
2207 if ($prohibited) {
2208 $ctxids = implode(',', $contextids);
2209 $roleids = implode(',', array_keys($prohibited));
2210 $joins[] = "LEFT JOIN {role_assignments} {$prefix}ra4 ON ({$prefix}ra4.userid = {$prefix}u.id AND {$prefix}ra4.roleid IN ($roleids) AND {$prefix}ra4.contextid IN ($ctxids))";
2211 $wheres[] = "{$prefix}ra4.id IS NULL";
2212 }
4f0c2d00 2213
e922fe23
PS
2214 if ($groupid) {
2215 $joins[] = "JOIN {groups_members} {$prefix}gm ON ({$prefix}gm.userid = {$prefix}u.id AND {$prefix}gm.groupid = :{$prefix}gmid)";
2216 $params["{$prefix}gmid"] = $groupid;
2217 }
2218 }
4f0c2d00 2219
e922fe23
PS
2220 } else {
2221 if ($groupid) {
2222 $joins[] = "JOIN {groups_members} {$prefix}gm ON ({$prefix}gm.userid = {$prefix}u.id AND {$prefix}gm.groupid = :{$prefix}gmid)";
2223 $params["{$prefix}gmid"] = $groupid;
4f0c2d00 2224 }
e922fe23 2225 }
4f0c2d00 2226
e922fe23
PS
2227 $wheres[] = "{$prefix}u.deleted = 0 AND {$prefix}u.id <> :{$prefix}guestid";
2228 $params["{$prefix}guestid"] = $CFG->siteguest;
2229
2230 if ($isfrontpage) {
2231 // all users are "enrolled" on the frontpage
4f0c2d00 2232 } else {
e922fe23
PS
2233 $joins[] = "JOIN {user_enrolments} {$prefix}ue ON {$prefix}ue.userid = {$prefix}u.id";
2234 $joins[] = "JOIN {enrol} {$prefix}e ON ({$prefix}e.id = {$prefix}ue.enrolid AND {$prefix}e.courseid = :{$prefix}courseid)";
2235 $params[$prefix.'courseid'] = $coursecontext->instanceid;
2236
2237 if ($onlyactive) {
2238 $wheres[] = "{$prefix}ue.status = :{$prefix}active AND {$prefix}e.status = :{$prefix}enabled";
2239 $wheres[] = "{$prefix}ue.timestart < :{$prefix}now1 AND ({$prefix}ue.timeend = 0 OR {$prefix}ue.timeend > :{$prefix}now2)";
2240 $now = round(time(), -2); // rounding helps caching in DB
2241 $params = array_merge($params, array($prefix.'enabled'=>ENROL_INSTANCE_ENABLED,
2242 $prefix.'active'=>ENROL_USER_ACTIVE,
2243 $prefix.'now1'=>$now, $prefix.'now2'=>$now));
2244 }
4f0c2d00 2245 }
e922fe23
PS
2246
2247 $joins = implode("\n", $joins);
2248 $wheres = "WHERE ".implode(" AND ", $wheres);
2249
2250 $sql = "SELECT DISTINCT {$prefix}u.id
2251 FROM {user} {$prefix}u
2252 $joins
2253 $wheres";
2254
2255 return array($sql, $params);
4f0c2d00
PS
2256}
2257
2258/**
e922fe23 2259 * Returns list of users enrolled into course.
4f0c2d00 2260 *
e922fe23
PS
2261 * @param context $context
2262 * @param string $withcapability
2263 * @param int $groupid 0 means ignore groups, any other value limits the result by group id
2264 * @param string $userfields requested user record fields
2265 * @param string $orderby
2266 * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
2267 * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
2268 * @return array of user records
4f0c2d00 2269 */
e922fe23
PS
2270function get_enrolled_users(context $context, $withcapability = '', $groupid = 0, $userfields = 'u.*', $orderby = '', $limitfrom = 0, $limitnum = 0) {
2271 global $DB;
5fd9e798 2272
e922fe23
PS
2273 list($esql, $params) = get_enrolled_sql($context, $withcapability, $groupid);
2274 $sql = "SELECT $userfields
2275 FROM {user} u
2276 JOIN ($esql) je ON je.id = u.id
2277 WHERE u.deleted = 0";
4f0c2d00 2278
e922fe23
PS
2279 if ($orderby) {
2280 $sql = "$sql ORDER BY $orderby";
4f0c2d00 2281 } else {
e922fe23 2282 $sql = "$sql ORDER BY u.lastname ASC, u.firstname ASC";
4f0c2d00
PS
2283 }
2284
e922fe23
PS
2285 return $DB->get_records_sql($sql, $params, $limitfrom, $limitnum);
2286}
4f0c2d00 2287
e922fe23
PS
2288/**
2289 * Counts list of users enrolled into course (as per above function)
2290 *
2291 * @param context $context
2292 * @param string $withcapability
2293 * @param int $groupid 0 means ignore groups, any other value limits the result by group id
2294 * @return array of user records
2295 */
2296function count_enrolled_users(context $context, $withcapability = '', $groupid = 0) {
2297 global $DB;
4f0c2d00 2298
e922fe23
PS
2299 list($esql, $params) = get_enrolled_sql($context, $withcapability, $groupid);
2300 $sql = "SELECT count(u.id)
2301 FROM {user} u
2302 JOIN ($esql) je ON je.id = u.id
2303 WHERE u.deleted = 0";
2304
2305 return $DB->count_records_sql($sql, $params);
2306}
2307
2308/**
2309 * Loads the capability definitions for the component (from file).
2310 *
2311 * Loads the capability definitions for the component (from file). If no
2312 * capabilities are defined for the component, we simply return an empty array.
2313 *
2314 * @param string $component full plugin name, examples: 'moodle', 'mod_forum'
2315 * @return array array of capabilities
2316 */
2317function load_capability_def($component) {
2318 $defpath = get_component_directory($component).'/db/access.php';
2319
2320 $capabilities = array();
2321 if (file_exists($defpath)) {
2322 require($defpath);
2323 if (!empty(${$component.'_capabilities'})) {
2324 // BC capability array name
2325 // since 2.0 we prefer $capabilities instead - it is easier to use and matches db/* files
99ddfdf4 2326 debugging('componentname_capabilities array is deprecated, please use $capabilities array only in access.php files');
e922fe23
PS
2327 $capabilities = ${$component.'_capabilities'};
2328 }
4f0c2d00
PS
2329 }
2330
e922fe23 2331 return $capabilities;
4f0c2d00
PS
2332}
2333
e922fe23
PS
2334/**
2335 * Gets the capabilities that have been cached in the database for this component.
2336 *
2337 * @param string $component - examples: 'moodle', 'mod_forum'
2338 * @return array array of capabilities
2339 */
2340function get_cached_capabilities($component = 'moodle') {
2341 global $DB;
2342 return $DB->get_records('capabilities', array('component'=>$component));
2343}
4f0c2d00
PS
2344
2345/**
e922fe23 2346 * Returns default capabilities for given role archetype.
4f0c2d00 2347 *
e922fe23
PS
2348 * @param string $archetype role archetype
2349 * @return array
4f0c2d00 2350 */
e922fe23
PS
2351function get_default_capabilities($archetype) {
2352 global $DB;
4f0c2d00 2353
e922fe23
PS
2354 if (!$archetype) {
2355 return array();
4f0c2d00
PS
2356 }
2357
e922fe23
PS
2358 $alldefs = array();
2359 $defaults = array();
2360 $components = array();
2361 $allcaps = $DB->get_records('capabilities');
4f0c2d00 2362
e922fe23
PS
2363 foreach ($allcaps as $cap) {
2364 if (!in_array($cap->component, $components)) {
2365 $components[] = $cap->component;
2366 $alldefs = array_merge($alldefs, load_capability_def($cap->component));
2367 }
2368 }
2369 foreach($alldefs as $name=>$def) {
2370 // Use array 'archetypes if available. Only if not specified, use 'legacy'.
2371 if (isset($def['archetypes'])) {
2372 if (isset($def['archetypes'][$archetype])) {
2373 $defaults[$name] = $def['archetypes'][$archetype];
2374 }
2375 // 'legacy' is for backward compatibility with 1.9 access.php
2376 } else {
2377 if (isset($def['legacy'][$archetype])) {
2378 $defaults[$name] = $def['legacy'][$archetype];
2379 }
2380 }
4f0c2d00
PS
2381 }
2382
e922fe23 2383 return $defaults;
4f0c2d00
PS
2384}
2385
2386/**
e922fe23
PS
2387 * Reset role capabilities to default according to selected role archetype.
2388 * If no archetype selected, removes all capabilities.
4f0c2d00 2389 *
e922fe23
PS
2390 * @param int $roleid
2391 * @return void
4f0c2d00 2392 */
e922fe23
PS
2393function reset_role_capabilities($roleid) {
2394 global $DB;
4f0c2d00 2395
e922fe23
PS
2396 $role = $DB->get_record('role', array('id'=>$roleid), '*', MUST_EXIST);
2397 $defaultcaps = get_default_capabilities($role->archetype);
4f0c2d00 2398
e922fe23 2399 $systemcontext = context_system::instance();
df997f84 2400
e922fe23 2401 $DB->delete_records('role_capabilities', array('roleid'=>$roleid));
4f0c2d00 2402
e922fe23
PS
2403 foreach($defaultcaps as $cap=>$permission) {
2404 assign_capability($cap, $permission, $roleid, $systemcontext->id);
4f0c2d00 2405 }
4f0c2d00
PS
2406}
2407
ed1d72ea 2408/**
e922fe23
PS
2409 * Updates the capabilities table with the component capability definitions.
2410 * If no parameters are given, the function updates the core moodle
2411 * capabilities.
ed1d72ea 2412 *
e922fe23
PS
2413 * Note that the absence of the db/access.php capabilities definition file
2414 * will cause any stored capabilities for the component to be removed from
2415 * the database.
ed1d72ea 2416 *
e922fe23
PS
2417 * @param string $component examples: 'moodle', 'mod/forum', 'block/quiz_results'
2418 * @return boolean true if success, exception in case of any problems
ed1d72ea 2419 */
e922fe23
PS
2420function update_capabilities($component = 'moodle') {
2421 global $DB, $OUTPUT;
ed1d72ea 2422
e922fe23 2423 $storedcaps = array();
ed1d72ea 2424
e922fe23
PS
2425 $filecaps = load_capability_def($component);
2426 foreach($filecaps as $capname=>$unused) {
2427 if (!preg_match('|^[a-z]+/[a-z_0-9]+:[a-z_0-9]+$|', $capname)) {
2428 debugging("Coding problem: Invalid capability name '$capname', use 'clonepermissionsfrom' field for migration.");
2429 }
ed1d72ea
SH
2430 }
2431
e922fe23
PS
2432 $cachedcaps = get_cached_capabilities($component);
2433 if ($cachedcaps) {
2434 foreach ($cachedcaps as $cachedcap) {
2435 array_push($storedcaps, $cachedcap->name);
2436 // update risk bitmasks and context levels in existing capabilities if needed
2437 if (array_key_exists($cachedcap->name, $filecaps)) {
2438 if (!array_key_exists('riskbitmask', $filecaps[$cachedcap->name])) {
2439 $filecaps[$cachedcap->name]['riskbitmask'] = 0; // no risk if not specified
2440 }
2441 if ($cachedcap->captype != $filecaps[$cachedcap->name]['captype']) {
2442 $updatecap = new stdClass();
2443 $updatecap->id = $cachedcap->id;
2444 $updatecap->captype = $filecaps[$cachedcap->name]['captype'];
2445 $DB->update_record('capabilities', $updatecap);
2446 }
2447 if ($cachedcap->riskbitmask != $filecaps[$cachedcap->name]['riskbitmask']) {
2448 $updatecap = new stdClass();
2449 $updatecap->id = $cachedcap->id;
2450 $updatecap->riskbitmask = $filecaps[$cachedcap->name]['riskbitmask'];
2451 $DB->update_record('capabilities', $updatecap);
2452 }
ed1d72ea 2453
e922fe23
PS
2454 if (!array_key_exists('contextlevel', $filecaps[$cachedcap->name])) {
2455 $filecaps[$cachedcap->name]['contextlevel'] = 0; // no context level defined
2456 }
2457 if ($cachedcap->contextlevel != $filecaps[$cachedcap->name]['contextlevel']) {
2458 $updatecap = new stdClass();
2459 $updatecap->id = $cachedcap->id;
2460 $updatecap->contextlevel = $filecaps[$cachedcap->name]['contextlevel'];
2461 $DB->update_record('capabilities', $updatecap);
2462 }
ed1d72ea 2463 }
e922fe23
PS
2464 }
2465 }
2466
2467 // Are there new capabilities in the file definition?
2468 $newcaps = array();
2469
2470 foreach ($filecaps as $filecap => $def) {
2471 if (!$storedcaps ||
2472 ($storedcaps && in_array($filecap, $storedcaps) === false)) {
2473 if (!array_key_exists('riskbitmask', $def)) {
2474 $def['riskbitmask'] = 0; // no risk if not specified
ed1d72ea 2475 }
e922fe23 2476 $newcaps[$filecap] = $def;
ed1d72ea
SH
2477 }
2478 }
e922fe23
PS
2479 // Add new capabilities to the stored definition.
2480 foreach ($newcaps as $capname => $capdef) {
2481 $capability = new stdClass();
2482 $capability->name = $capname;
2483 $capability->captype = $capdef['captype'];
2484 $capability->contextlevel = $capdef['contextlevel'];
2485 $capability->component = $component;
2486 $capability->riskbitmask = $capdef['riskbitmask'];
ed1d72ea 2487
e922fe23
PS
2488 $DB->insert_record('capabilities', $capability, false);
2489
2490 if (isset($capdef['clonepermissionsfrom']) && in_array($capdef['clonepermissionsfrom'], $storedcaps)){
2491 if ($rolecapabilities = $DB->get_records('role_capabilities', array('capability'=>$capdef['clonepermissionsfrom']))){
2492 foreach ($rolecapabilities as $rolecapability){
2493 //assign_capability will update rather than insert if capability exists
2494 if (!assign_capability($capname, $rolecapability->permission,
2495 $rolecapability->roleid, $rolecapability->contextid, true)){
2496 echo $OUTPUT->notification('Could not clone capabilities for '.$capname);
2497 }
2498 }
2499 }
2500 // we ignore archetype key if we have cloned permissions
2501 } else if (isset($capdef['archetypes']) && is_array($capdef['archetypes'])) {
2502 assign_legacy_capabilities($capname, $capdef['archetypes']);
2503 // 'legacy' is for backward compatibility with 1.9 access.php
2504 } else if (isset($capdef['legacy']) && is_array($capdef['legacy'])) {
2505 assign_legacy_capabilities($capname, $capdef['legacy']);
ed1d72ea
SH
2506 }
2507 }
e922fe23
PS
2508 // Are there any capabilities that have been removed from the file
2509 // definition that we need to delete from the stored capabilities and
2510 // role assignments?
2511 capabilities_cleanup($component, $filecaps);
2512
2513 // reset static caches
2514 accesslib_clear_all_caches(false);
2515
2516 return true;
ed1d72ea
SH
2517}
2518
4f0c2d00 2519/**
e922fe23
PS
2520 * Deletes cached capabilities that are no longer needed by the component.
2521 * Also unassigns these capabilities from any roles that have them.
df997f84 2522 *
e922fe23
PS
2523 * @param string $component examples: 'moodle', 'mod_forum', 'block_quiz_results'
2524 * @param array $newcapdef array of the new capability definitions that will be
2525 * compared with the cached capabilities
2526 * @return int number of deprecated capabilities that have been removed
4f0c2d00 2527 */
e922fe23
PS
2528function capabilities_cleanup($component, $newcapdef = null) {
2529 global $DB;
4f0c2d00 2530
e922fe23 2531 $removedcount = 0;
4f0c2d00 2532
e922fe23
PS
2533 if ($cachedcaps = get_cached_capabilities($component)) {
2534 foreach ($cachedcaps as $cachedcap) {
2535 if (empty($newcapdef) ||
2536 array_key_exists($cachedcap->name, $newcapdef) === false) {
4f0c2d00 2537
e922fe23
PS
2538 // Remove from capabilities cache.
2539 $DB->delete_records('capabilities', array('name'=>$cachedcap->name));
2540 $removedcount++;
2541 // Delete from roles.
2542 if ($roles = get_roles_with_capability($cachedcap->name)) {
2543 foreach($roles as $role) {
2544 if (!unassign_capability($cachedcap->name, $role->id)) {
2545 print_error('cannotunassigncap', 'error', '', (object)array('cap'=>$cachedcap->name, 'role'=>$role->name));
2546 }
2547 }
2548 }
2549 } // End if.
2550 }
2551 }
2552 return $removedcount;
2553}
2554
e922fe23
PS
2555/**
2556 * Returns an array of all the known types of risk
2557 * The array keys can be used, for example as CSS class names, or in calls to
2558 * print_risk_icon. The values are the corresponding RISK_ constants.
2559 *
2560 * @return array all the known types of risk.
2561 */
2562function get_all_risks() {
2563 return array(
2564 'riskmanagetrust' => RISK_MANAGETRUST,
2565 'riskconfig' => RISK_CONFIG,
2566 'riskxss' => RISK_XSS,
2567 'riskpersonal' => RISK_PERSONAL,
2568 'riskspam' => RISK_SPAM,
2569 'riskdataloss' => RISK_DATALOSS,
2570 );
2571}
2572
2573/**
2574 * Return a link to moodle docs for a given capability name
2575 *
2576 * @param object $capability a capability - a row from the mdl_capabilities table.
2577 * @return string the human-readable capability name as a link to Moodle Docs.
2578 */
2579function get_capability_docs_link($capability) {
2580 $url = get_docs_url('Capabilities/' . $capability->name);
2581 return '<a onclick="this.target=\'docspopup\'" href="' . $url . '">' . get_capability_string($capability->name) . '</a>';
2582}
2583
2584/**
2585 * This function pulls out all the resolved capabilities (overrides and
2586 * defaults) of a role used in capability overrides in contexts at a given
2587 * context.
2588 *
2589 * @param context $context
2590 * @param int $roleid
2591 * @param string $cap capability, optional, defaults to ''
2592 * @return array of capabilities
2593 */
2594function role_context_capabilities($roleid, context $context, $cap = '') {
2595 global $DB;
2596
2597 $contexts = $context->get_parent_context_ids(true);
2598 $contexts = '('.implode(',', $contexts).')';
2599
2600 $params = array($roleid);
2601
2602 if ($cap) {
2603 $search = " AND rc.capability = ? ";
2604 $params[] = $cap;
2605 } else {
2606 $search = '';
2607 }
2608
2609 $sql = "SELECT rc.*
2610 FROM {role_capabilities} rc, {context} c
2611 WHERE rc.contextid in $contexts
2612 AND rc.roleid = ?
2613 AND rc.contextid = c.id $search
2614 ORDER BY c.contextlevel DESC, rc.capability DESC";
2615
2616 $capabilities = array();
2617
2618 if ($records = $DB->get_records_sql($sql, $params)) {
2619 // We are traversing via reverse order.
2620 foreach ($records as $record) {
2621 // If not set yet (i.e. inherit or not set at all), or currently we have a prohibit
2622 if (!isset($capabilities[$record->capability]) || $record->permission<-500) {
2623 $capabilities[$record->capability] = $record->permission;
2624 }
2625 }
2626 }
2627 return $capabilities;
2628}
2629
2630/**
2631 * Constructs array with contextids as first parameter and context paths,
2632 * in both cases bottom top including self.
2633 *
2634 * @private
2635 * @param context $context
2636 * @return array
2637 */
2638function get_context_info_list(context $context) {
2639 $contextids = explode('/', ltrim($context->path, '/'));
2640 $contextpaths = array();
2641 $contextids2 = $contextids;
2642 while ($contextids2) {
2643 $contextpaths[] = '/' . implode('/', $contextids2);
2644 array_pop($contextids2);
2645 }
2646 return array($contextids, $contextpaths);
2647}
2648
2649/**
2650 * Check if context is the front page context or a context inside it
2651 *
2652 * Returns true if this context is the front page context, or a context inside it,
2653 * otherwise false.
2654 *
2655 * @param context $context a context object.
2656 * @return bool
2657 */
2658function is_inside_frontpage(context $context) {
2659 $frontpagecontext = context_course::instance(SITEID);
2660 return strpos($context->path . '/', $frontpagecontext->path . '/') === 0;
2661}
2662
2663/**
2664 * Returns capability information (cached)
2665 *
2666 * @param string $capabilityname
2667 * @return object or null if capability not found
2668 */
2669function get_capability_info($capabilityname) {
2670 global $ACCESSLIB_PRIVATE, $DB; // one request per page only
2671
2672 //TODO: MUC - this could be cached in shared memory, it would eliminate 1 query per page
2673
2674 if (empty($ACCESSLIB_PRIVATE->capabilities)) {
2675 $ACCESSLIB_PRIVATE->capabilities = array();
2676 $caps = $DB->get_records('capabilities', array(), 'id, name, captype, riskbitmask');
2677 foreach ($caps as $cap) {
2678 $capname = $cap->name;
2679 unset($cap->id);
2680 unset($cap->name);
2681 $cap->riskbitmask = (int)$cap->riskbitmask;
2682 $ACCESSLIB_PRIVATE->capabilities[$capname] = $cap;
2683 }
2684 }
2685
2686 return isset($ACCESSLIB_PRIVATE->capabilities[$capabilityname]) ? $ACCESSLIB_PRIVATE->capabilities[$capabilityname] : null;
2687}
2688
2689/**
2690 * Returns the human-readable, translated version of the capability.
2691 * Basically a big switch statement.
2692 *
2693 * @param string $capabilityname e.g. mod/choice:readresponses
2694 * @return string
2695 */
2696function get_capability_string($capabilityname) {
2697
2698 // Typical capability name is 'plugintype/pluginname:capabilityname'
2699 list($type, $name, $capname) = preg_split('|[/:]|', $capabilityname);
2700
2701 if ($type === 'moodle') {
2702 $component = 'core_role';
2703 } else if ($type === 'quizreport') {
2704 //ugly hack!!
2705 $component = 'quiz_'.$name;
2706 } else {
2707 $component = $type.'_'.$name;
2708 }
2709
2710 $stringname = $name.':'.$capname;
2711
2712 if ($component === 'core_role' or get_string_manager()->string_exists($stringname, $component)) {
2713 return get_string($stringname, $component);
2714 }
2715
2716 $dir = get_component_directory($component);
2717 if (!file_exists($dir)) {
2718 // plugin broken or does not exist, do not bother with printing of debug message
2719 return $capabilityname.' ???';
2720 }
2721
2722 // something is wrong in plugin, better print debug
2723 return get_string($stringname, $component);
2724}
2725
2726/**
2727 * This gets the mod/block/course/core etc strings.
2728 *
2729 * @param string $component
2730 * @param int $contextlevel
2731 * @return string|bool String is success, false if failed
2732 */
2733function get_component_string($component, $contextlevel) {
2734
2735 if ($component === 'moodle' or $component === 'core') {
2736 switch ($contextlevel) {
2737 // TODO: this should probably use context level names instead
2738 case CONTEXT_SYSTEM: return get_string('coresystem');
2739 case CONTEXT_USER: return get_string('users');
2740 case CONTEXT_COURSECAT: return get_string('categories');
2741 case CONTEXT_COURSE: return get_string('course');
2742 case CONTEXT_MODULE: return get_string('activities');
2743 case CONTEXT_BLOCK: return get_string('block');
2744 default: print_error('unknowncontext');
2745 }
2746 }
2747
2748 list($type, $name) = normalize_component($component);
2749 $dir = get_plugin_directory($type, $name);
2750 if (!file_exists($dir)) {
2751 // plugin not installed, bad luck, there is no way to find the name
2752 return $component.' ???';
2753 }
2754
2755 switch ($type) {
2756 // TODO: this is really hacky, anyway it should be probably moved to lib/pluginlib.php
2757 case 'quiz': return get_string($name.':componentname', $component);// insane hack!!!
2758 case 'repository': return get_string('repository', 'repository').': '.get_string('pluginname', $component);
2759 case 'gradeimport': return get_string('gradeimport', 'grades').': '.get_string('pluginname', $component);
2760 case 'gradeexport': return get_string('gradeexport', 'grades').': '.get_string('pluginname', $component);
2761 case 'gradereport': return get_string('gradereport', 'grades').': '.get_string('pluginname', $component);
2762 case 'webservice': return get_string('webservice', 'webservice').': '.get_string('pluginname', $component);
2763 case 'block': return get_string('block').': '.get_string('pluginname', basename($component));
2764 case 'mod':
2765 if (get_string_manager()->string_exists('pluginname', $component)) {
2766 return get_string('activity').': '.get_string('pluginname', $component);
2767 } else {
2768 return get_string('activity').': '.get_string('modulename', $component);
2769 }
2770 default: return get_string('pluginname', $component);
2771 }
2772}
2773
2774/**
2775 * Gets the list of roles assigned to this context and up (parents)
2776 * from the list of roles that are visible on user profile page
2777 * and participants page.
2778 *
2779 * @param context $context
2780 * @return array
2781 */
2782function get_profile_roles(context $context) {
2783 global $CFG, $DB;
2784
2785 if (empty($CFG->profileroles)) {
2786 return array();
2787 }
2788
2789 list($rallowed, $params) = $DB->get_in_or_equal(explode(',', $CFG->profileroles), SQL_PARAMS_NAMED, 'a');
2790 list($contextlist, $cparams) = $DB->get_in_or_equal($context->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'p');
2791 $params = array_merge($params, $cparams);
2792
2793 $sql = "SELECT DISTINCT r.id, r.name, r.shortname, r.sortorder
2794 FROM {role_assignments} ra, {role} r
2795 WHERE r.id = ra.roleid
2796 AND ra.contextid $contextlist
2797 AND r.id $rallowed
2798 ORDER BY r.sortorder ASC";
2799
2800 return $DB->get_records_sql($sql, $params);
2801}
2802
2803/**
2804 * Gets the list of roles assigned to this context and up (parents)
2805 *
2806 * @param context $context
2807 * @return array
2808 */
2809function get_roles_used_in_context(context $context) {
2810 global $DB;
2811
2812 list($contextlist, $params) = $DB->get_in_or_equal($context->get_parent_context_ids(true));
2813
2814 $sql = "SELECT DISTINCT r.id, r.name, r.shortname, r.sortorder
2815 FROM {role_assignments} ra, {role} r
2816 WHERE r.id = ra.roleid
2817 AND ra.contextid $contextlist
2818 ORDER BY r.sortorder ASC";
2819
2820 return $DB->get_records_sql($sql, $params);
2821}
2822
2823/**
2824 * This function is used to print roles column in user profile page.
2825 * It is using the CFG->profileroles to limit the list to only interesting roles.
2826 * (The permission tab has full details of user role assignments.)
2827 *
2828 * @param int $userid
2829 * @param int $courseid
2830 * @return string
2831 */
2832function get_user_roles_in_course($userid, $courseid) {
2833 global $CFG, $DB;
2834
2835 if (empty($CFG->profileroles)) {
2836 return '';
2837 }
2838
2839 if ($courseid == SITEID) {
2840 $context = context_system::instance();
2841 } else {
2842 $context = context_course::instance($courseid);
2843 }
2844
2845 if (empty($CFG->profileroles)) {
2846 return array();
2847 }
2848
2849 list($rallowed, $params) = $DB->get_in_or_equal(explode(',', $CFG->profileroles), SQL_PARAMS_NAMED, 'a');
2850 list($contextlist, $cparams) = $DB->get_in_or_equal($context->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'p');
2851 $params = array_merge($params, $cparams);
2852
2853 $sql = "SELECT DISTINCT r.id, r.name, r.shortname, r.sortorder
2854 FROM {role_assignments} ra, {role} r
2855 WHERE r.id = ra.roleid
2856 AND ra.contextid $contextlist
2857 AND r.id $rallowed
2858 AND ra.userid = :userid
2859 ORDER BY r.sortorder ASC";
2860 $params['userid'] = $userid;
2861
2862 $rolestring = '';
2863
2864 if ($roles = $DB->get_records_sql($sql, $params)) {
2865 foreach ($roles as $userrole) {
2866 $rolenames[$userrole->id] = $userrole->name;
2867 }
2868
2869 $rolenames = role_fix_names($rolenames, $context); // Substitute aliases
2870
2871 foreach ($rolenames as $roleid => $rolename) {
2872 $rolenames[$roleid] = '<a href="'.$CFG->wwwroot.'/user/index.php?contextid='.$context->id.'&amp;roleid='.$roleid.'">'.$rolename.'</a>';
2873 }
2874 $rolestring = implode(',', $rolenames);
2875 }
2876
2877 return $rolestring;
2878}
2879
2880/**
2881 * Checks if a user can assign users to a particular role in this context
2882 *
2883 * @param context $context
2884 * @param int $targetroleid - the id of the role you want to assign users to
2885 * @return boolean
2886 */
2887function user_can_assign(context $context, $targetroleid) {
2888 global $DB;
2889
2890 // first check if user has override capability
2891 // if not return false;
2892 if (!has_capability('moodle/role:assign', $context)) {
2893 return false;
2894 }
2895 // pull out all active roles of this user from this context(or above)
2896 if ($userroles = get_user_roles($context)) {
2897 foreach ($userroles as $userrole) {
2898 // if any in the role_allow_override table, then it's ok
2899 if ($DB->get_record('role_allow_assign', array('roleid'=>$userrole->roleid, 'allowassign'=>$targetroleid))) {
2900 return true;
2901 }
2902 }
2903 }
2904
2905 return false;
2906}
2907
2908/**
2909 * Returns all site roles in correct sort order.
2910 *
2911 * @return array
2912 */
2913function get_all_roles() {
2914 global $DB;
2915 return $DB->get_records('role', null, 'sortorder ASC');
2916}
2917
2918/**
2919 * Returns roles of a specified archetype
2920 *
2921 * @param string $archetype
2922 * @return array of full role records
2923 */
2924function get_archetype_roles($archetype) {
2925 global $DB;
2926 return $DB->get_records('role', array('archetype'=>$archetype), 'sortorder ASC');
2927}
2928
2929/**
2930 * Gets all the user roles assigned in this context, or higher contexts
2931 * this is mainly used when checking if a user can assign a role, or overriding a role
2932 * i.e. we need to know what this user holds, in order to verify against allow_assign and
2933 * allow_override tables
2934 *
2935 * @param context $context
2936 * @param int $userid
2937 * @param bool $checkparentcontexts defaults to true
2938 * @param string $order defaults to 'c.contextlevel DESC, r.sortorder ASC'
2939 * @return array
2940 */
2941function get_user_roles(context $context, $userid = 0, $checkparentcontexts = true, $order = 'c.contextlevel DESC, r.sortorder ASC') {
2942 global $USER, $DB;
2943
2944 if (empty($userid)) {
2945 if (empty($USER->id)) {
2946 return array();
2947 }
2948 $userid = $USER->id;
2949 }
2950
2951 if ($checkparentcontexts) {
2952 $contextids = $context->get_parent_context_ids();
2953 } else {
2954 $contextids = array();
2955 }
2956 $contextids[] = $context->id;
2957
2958 list($contextids, $params) = $DB->get_in_or_equal($contextids, SQL_PARAMS_QM);
2959
2960 array_unshift($params, $userid);
2961
2962 $sql = "SELECT ra.*, r.name, r.shortname
2963 FROM {role_assignments} ra, {role} r, {context} c
2964 WHERE ra.userid = ?
2965 AND ra.roleid = r.id
2966 AND ra.contextid = c.id
2967 AND ra.contextid $contextids
2968 ORDER BY $order";
2969
2970 return $DB->get_records_sql($sql ,$params);
2971}
2972
2973/**
2974 * Creates a record in the role_allow_override table
2975 *
2976 * @param int $sroleid source roleid
2977 * @param int $troleid target roleid
2978 * @return void
2979 */
2980function allow_override($sroleid, $troleid) {
2981 global $DB;
2982
2983 $record = new stdClass();
2984 $record->roleid = $sroleid;
2985 $record->allowoverride = $troleid;
2986 $DB->insert_record('role_allow_override', $record);
2987}
2988
2989/**
2990 * Creates a record in the role_allow_assign table
2991 *
2992 * @param int $fromroleid source roleid
2993 * @param int $targetroleid target roleid
2994 * @return void
2995 */
2996function allow_assign($fromroleid, $targetroleid) {
2997 global $DB;
2998
2999 $record = new stdClass();
3000 $record->roleid = $fromroleid;
3001 $record->allowassign = $targetroleid;
3002 $DB->insert_record('role_allow_assign', $record);
3003}
3004
3005/**
3006 * Creates a record in the role_allow_switch table
3007 *
3008 * @param int $fromroleid source roleid
3009 * @param int $targetroleid target roleid
3010 * @return void
3011 */
3012function allow_switch($fromroleid, $targetroleid) {
3013 global $DB;
3014
3015 $record = new stdClass();
3016 $record->roleid = $fromroleid;
3017 $record->allowswitch = $targetroleid;
3018 $DB->insert_record('role_allow_switch', $record);
3019}
3020
3021/**
3022 * Gets a list of roles that this user can assign in this context
3023 *
3024 * @param context $context the context.
3025 * @param int $rolenamedisplay the type of role name to display. One of the
3026 * ROLENAME_X constants. Default ROLENAME_ALIAS.
3027 * @param bool $withusercounts if true, count the number of users with each role.
3028 * @param integer|object $user A user id or object. By default (null) checks the permissions of the current user.
3029 * @return array if $withusercounts is false, then an array $roleid => $rolename.
3030 * if $withusercounts is true, returns a list of three arrays,
3031 * $rolenames, $rolecounts, and $nameswithcounts.
3032 */
3033function get_assignable_roles(context $context, $rolenamedisplay = ROLENAME_ALIAS, $withusercounts = false, $user = null) {
3034 global $USER, $DB;
3035
3036 // make sure there is a real user specified
3037 if ($user === null) {
3038 $userid = isset($USER->id) ? $USER->id : 0;
3039 } else {
3040 $userid = is_object($user) ? $user->id : $user;
3041 }
3042
3043 if (!has_capability('moodle/role:assign', $context, $userid)) {
3044 if ($withusercounts) {
3045 return array(array(), array(), array());
3046 } else {
3047 return array();
3048 }
3049 }
3050
3051 $parents = $context->get_parent_context_ids(true);
3052 $contexts = implode(',' , $parents);
3053
3054 $params = array();
3055 $extrafields = '';
3056 if ($rolenamedisplay == ROLENAME_ORIGINALANDSHORT or $rolenamedisplay == ROLENAME_SHORT) {
3057 $extrafields .= ', r.shortname';
3058 }
3059
3060 if ($withusercounts) {
3061 $extrafields = ', (SELECT count(u.id)
3062 FROM {role_assignments} cra JOIN {user} u ON cra.userid = u.id
3063 WHERE cra.roleid = r.id AND cra.contextid = :conid AND u.deleted = 0
3064 ) AS usercount';
3065 $params['conid'] = $context->id;
3066 }
3067
3068 if (is_siteadmin($userid)) {
3069 // show all roles allowed in this context to admins
3070 $assignrestriction = "";
3071 } else {
3072 $assignrestriction = "JOIN (SELECT DISTINCT raa.allowassign AS id
3073 FROM {role_allow_assign} raa
3074 JOIN {role_assignments} ra ON ra.roleid = raa.roleid
3075 WHERE ra.userid = :userid AND ra.contextid IN ($contexts)
3076 ) ar ON ar.id = r.id";
3077 $params['userid'] = $userid;
3078 }
3079 $params['contextlevel'] = $context->contextlevel;
3080 $sql = "SELECT r.id, r.name $extrafields
3081 FROM {role} r
3082 $assignrestriction
3083 JOIN {role_context_levels} rcl ON r.id = rcl.roleid
3084 WHERE rcl.contextlevel = :contextlevel
3085 ORDER BY r.sortorder ASC";
3086 $roles = $DB->get_records_sql($sql, $params);
3087
3088 $rolenames = array();
3089 foreach ($roles as $role) {
3090 if ($rolenamedisplay == ROLENAME_SHORT) {
3091 $rolenames[$role->id] = $role->shortname;
3092 continue;
3093 }
3094 $rolenames[$role->id] = $role->name;
3095 if ($rolenamedisplay == ROLENAME_ORIGINALANDSHORT) {
3096 $rolenames[$role->id] .= ' (' . $role->shortname . ')';
3097 }
3098 }
3099 if ($rolenamedisplay != ROLENAME_ORIGINALANDSHORT and $rolenamedisplay != ROLENAME_SHORT) {
3100 $rolenames = role_fix_names($rolenames, $context, $rolenamedisplay);
3101 }
3102
3103 if (!$withusercounts) {
3104 return $rolenames;
3105 }
3106
3107 $rolecounts = array();
3108 $nameswithcounts = array();
3109 foreach ($roles as $role) {
3110 $nameswithcounts[$role->id] = $rolenames[$role->id] . ' (' . $roles[$role->id]->usercount . ')';
3111 $rolecounts[$role->id] = $roles[$role->id]->usercount;
3112 }
3113 return array($rolenames, $rolecounts, $nameswithcounts);
3114}
3115
3116/**
3117 * Gets a list of roles that this user can switch to in a context
3118 *
3119 * Gets a list of roles that this user can switch to in a context, for the switchrole menu.
3120 * This function just process the contents of the role_allow_switch table. You also need to
3121 * test the moodle/role:switchroles to see if the user is allowed to switch in the first place.
3122 *
3123 * @param context $context a context.
3124 * @return array an array $roleid => $rolename.
3125 */
3126function get_switchable_roles(context $context) {
3127 global $USER, $DB;
3128
3129 $params = array();
3130 $extrajoins = '';
3131 $extrawhere = '';
3132 if (!is_siteadmin()) {
3133 // Admins are allowed to switch to any role with.
3134 // Others are subject to the additional constraint that the switch-to role must be allowed by
3135 // 'role_allow_switch' for some role they have assigned in this context or any parent.
3136 $parents = $context->get_parent_context_ids(true);
3137 $contexts = implode(',' , $parents);
3138
3139 $extrajoins = "JOIN {role_allow_switch} ras ON ras.allowswitch = rc.roleid
3140 JOIN {role_assignments} ra ON ra.roleid = ras.roleid";
3141 $extrawhere = "WHERE ra.userid = :userid AND ra.contextid IN ($contexts)";
3142 $params['userid'] = $USER->id;
3143 }
3144
3145 $query = "
3146 SELECT r.id, r.name
3147 FROM (SELECT DISTINCT rc.roleid
3148 FROM {role_capabilities} rc
3149 $extrajoins
3150 $extrawhere) idlist
3151 JOIN {role} r ON r.id = idlist.roleid
3152 ORDER BY r.sortorder";
3153
3154 $rolenames = $DB->get_records_sql_menu($query, $params);
3155 return role_fix_names($rolenames, $context, ROLENAME_ALIAS);
3156}
3157
3158/**
3159 * Gets a list of roles that this user can override in this context.
3160 *
3161 * @param context $context the context.
3162 * @param int $rolenamedisplay the type of role name to display. One of the
3163 * ROLENAME_X constants. Default ROLENAME_ALIAS.
3164 * @param bool $withcounts if true, count the number of overrides that are set for each role.
3165 * @return array if $withcounts is false, then an array $roleid => $rolename.
3166 * if $withusercounts is true, returns a list of three arrays,
3167 * $rolenames, $rolecounts, and $nameswithcounts.
3168 */
3169function get_overridable_roles(context $context, $rolenamedisplay = ROLENAME_ALIAS, $withcounts = false) {
3170 global $USER, $DB;
3171
3172 if (!has_any_capability(array('moodle/role:safeoverride', 'moodle/role:override'), $context)) {
3173 if ($withcounts) {
3174 return array(array(), array(), array());
3175 } else {
3176 return array();
3177 }
3178 }
3179
3180 $parents = $context->get_parent_context_ids(true);
3181 $contexts = implode(',' , $parents);
3182
3183 $params = array();
3184 $extrafields = '';
3185 if ($rolenamedisplay == ROLENAME_ORIGINALANDSHORT) {
3186 $extrafields .= ', ro.shortname';
3187 }
3188
3189 $params['userid'] = $USER->id;
3190 if ($withcounts) {
3191 $extrafields = ', (SELECT COUNT(rc.id) FROM {role_capabilities} rc
3192 WHERE rc.roleid = ro.id AND rc.contextid = :conid) AS overridecount';
3193 $params['conid'] = $context->id;
3194 }
3195
3196 if (is_siteadmin()) {
3197 // show all roles to admins
3198 $roles = $DB->get_records_sql("
3199 SELECT ro.id, ro.name$extrafields
3200 FROM {role} ro
3201 ORDER BY ro.sortorder ASC", $params);
3202
3203 } else {
3204 $roles = $DB->get_records_sql("
3205 SELECT ro.id, ro.name$extrafields
3206 FROM {role} ro
3207 JOIN (SELECT DISTINCT r.id
3208 FROM {role} r
3209 JOIN {role_allow_override} rao ON r.id = rao.allowoverride
3210 JOIN {role_assignments} ra ON rao.roleid = ra.roleid
3211 WHERE ra.userid = :userid AND ra.contextid IN ($contexts)
3212 ) inline_view ON ro.id = inline_view.id
3213 ORDER BY ro.sortorder ASC", $params);
3214 }
3215
3216 $rolenames = array();
3217 foreach ($roles as $role) {
3218 $rolenames[$role->id] = $role->name;
3219 if ($rolenamedisplay == ROLENAME_ORIGINALANDSHORT) {
3220 $rolenames[$role->id] .= ' (' . $role->shortname . ')';
3221 }
3222 }
3223 if ($rolenamedisplay != ROLENAME_ORIGINALANDSHORT) {
3224 $rolenames = role_fix_names($rolenames, $context, $rolenamedisplay);
3225 }
3226
3227 if (!$withcounts) {
3228 return $rolenames;
3229}
3230
3231 $rolecounts = array();
3232 $nameswithcounts = array();
3233 foreach ($roles as $role) {
3234 $nameswithcounts[$role->id] = $rolenames[$role->id] . ' (' . $roles[$role->id]->overridecount . ')';
3235 $rolecounts[$role->id] = $roles[$role->id]->overridecount;
3236 }
3237 return array($rolenames, $rolecounts, $nameswithcounts);
3238}
3239
3240/**
3241 * Create a role menu suitable for default role selection in enrol plugins.
3242 * @param context $context
3243 * @param int $addroleid current or default role - always added to list
3244 * @return array roleid=>localised role name
3245 */
3246function get_default_enrol_roles(context $context, $addroleid = null) {
3247 global $DB;
3248
3249 $params = array('contextlevel'=>CONTEXT_COURSE);
3250 if ($addroleid) {
3251 $addrole = "OR r.id = :addroleid";
3252 $params['addroleid'] = $addroleid;
3253 } else {
3254 $addrole = "";
3255 }
3256 $sql = "SELECT r.id, r.name
3257 FROM {role} r
3258 LEFT JOIN {role_context_levels} rcl ON (rcl.roleid = r.id AND rcl.contextlevel = :contextlevel)
3259 WHERE rcl.id IS NOT NULL $addrole
3260 ORDER BY sortorder DESC";
3261
3262 $roles = $DB->get_records_sql_menu($sql, $params);
3263 $roles = role_fix_names($roles, $context, ROLENAME_BOTH);
3264
3265 return $roles;
3266}
3267
3268/**
3269 * Return context levels where this role is assignable.
3270 * @param integer $roleid the id of a role.
3271 * @return array list of the context levels at which this role may be assigned.
3272 */
3273function get_role_contextlevels($roleid) {
3274 global $DB;
3275 return $DB->get_records_menu('role_context_levels', array('roleid' => $roleid),
3276 'contextlevel', 'id,contextlevel');
3277}
3278
3279/**
3280 * Return roles suitable for assignment at the specified context level.
3281 *
3282 * NOTE: this function name looks like a typo, should be probably get_roles_for_contextlevel()
3283 *
3284 * @param integer $contextlevel a contextlevel.
3285 * @return array list of role ids that are assignable at this context level.
3286 */
3287function get_roles_for_contextlevels($contextlevel) {
3288 global $DB;
3289 return $DB->get_records_menu('role_context_levels', array('contextlevel' => $contextlevel),
3290 '', 'id,roleid');
3291}
3292
3293/**
3294 * Returns default context levels where roles can be assigned.
3295 *
3296 * @param string $rolearchetype one of the role archetypes - that is, one of the keys
3297 * from the array returned by get_role_archetypes();
3298 * @return array list of the context levels at which this type of role may be assigned by default.
3299 */
3300function get_default_contextlevels($rolearchetype) {
3301 static $defaults = array(
3302 'manager' => array(CONTEXT_SYSTEM, CONTEXT_COURSECAT, CONTEXT_COURSE),
3303 'coursecreator' => array(CONTEXT_SYSTEM, CONTEXT_COURSECAT),
3304 'editingteacher' => array(CONTEXT_COURSE, CONTEXT_MODULE),
3305 'teacher' => array(CONTEXT_COURSE, CONTEXT_MODULE),
3306 'student' => array(CONTEXT_COURSE, CONTEXT_MODULE),
3307 'guest' => array(),
3308 'user' => array(),
3309 'frontpage' => array());
3310
3311 if (isset($defaults[$rolearchetype])) {
3312 return $defaults[$rolearchetype];
3313 } else {
3314 return array();
3315 }
3316}
3317
3318/**
3319 * Set the context levels at which a particular role can be assigned.
3320 * Throws exceptions in case of error.
3321 *
3322 * @param integer $roleid the id of a role.
3323 * @param array $contextlevels the context levels at which this role should be assignable,
3324 * duplicate levels are removed.
3325 * @return void
3326 */
3327function set_role_contextlevels($roleid, array $contextlevels) {
3328 global $DB;
3329 $DB->delete_records('role_context_levels', array('roleid' => $roleid));
3330 $rcl = new stdClass();
3331 $rcl->roleid = $roleid;
3332 $contextlevels = array_unique($contextlevels);
3333 foreach ($contextlevels as $level) {
3334 $rcl->contextlevel = $level;
3335 $DB->insert_record('role_context_levels', $rcl, false, true);
3336 }
3337}
4f0c2d00 3338
e922fe23
PS
3339/**
3340 * Who has this capability in this context?
3341 *
3342 * This can be a very expensive call - use sparingly and keep
3343 * the results if you are going to need them again soon.
3344 *
3345 * Note if $fields is empty this function attempts to get u.*
3346 * which can get rather large - and has a serious perf impact
3347 * on some DBs.
3348 *
3349 * @param context $context
3350 * @param string|array $capability - capability name(s)
3351 * @param string $fields - fields to be pulled. The user table is aliased to 'u'. u.id MUST be included.
3352 * @param string $sort - the sort order. Default is lastaccess time.
3353 * @param mixed $limitfrom - number of records to skip (offset)
3354 * @param mixed $limitnum - number of records to fetch