MDL-45678 cache: renamed new cache and better comments
[moodle.git] / lib / accesslib.php
CommitLineData
46808d7c 1<?php
117bd748
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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
e922fe23
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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)
f76249cc
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36 * - is_enrolled()
37 * - is_viewing()
38 * - is_guest()
e922fe23 39 * - is_siteadmin()
f76249cc
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40 * - isguestuser()
41 * - isloggedin()
dcd6a775 42 *
43 * What courses has this user access to?
e922fe23 44 * - get_enrolled_users()
dcd6a775 45 *
db70c4bd 46 * What users can do X in this context?
f76249cc
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47 * - get_enrolled_users() - at and bellow course context
48 * - get_users_by_capability() - above course context
db70c4bd 49 *
e922fe23
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50 * Modify roles
51 * - role_assign()
52 * - role_unassign()
53 * - role_unassign_all()
5a4e7398 54 *
e922fe23 55 * Advanced - for internal use only
dcd6a775 56 * - load_all_capabilities()
57 * - reload_all_capabilities()
bb2c22bd 58 * - has_capability_in_accessdata()
dcd6a775 59 * - get_user_access_sitewide()
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60 * - load_course_context()
61 * - load_role_access_by_context()
62 * - etc.
dcd6a775 63 *
cc3edaa4 64 * <b>Name conventions</b>
5a4e7398 65 *
cc3edaa4 66 * "ctx" means context
92e53168 67 *
cc3edaa4 68 * <b>accessdata</b>
92e53168 69 *
70 * Access control data is held in the "accessdata" array
71 * which - for the logged-in user, will be in $USER->access
5a4e7398 72 *
d867e696 73 * For other users can be generated and passed around (but may also be cached
e922fe23 74 * against userid in $ACCESSLIB_PRIVATE->accessdatabyuser).
92e53168 75 *
bb2c22bd 76 * $accessdata is a multidimensional array, holding
5a4e7398 77 * role assignments (RAs), role-capabilities-perm sets
51be70d2 78 * (role defs) and a list of courses we have loaded
92e53168 79 * data for.
80 *
5a4e7398 81 * Things are keyed on "contextpaths" (the path field of
92e53168 82 * the context table) for fast walking up/down the tree.
cc3edaa4 83 * <code>
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84 * $accessdata['ra'][$contextpath] = array($roleid=>$roleid)
85 * [$contextpath] = array($roleid=>$roleid)
86 * [$contextpath] = array($roleid=>$roleid)
117bd748 87 * </code>
92e53168 88 *
89 * Role definitions are stored like this
90 * (no cap merge is done - so it's compact)
91 *
cc3edaa4 92 * <code>
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93 * $accessdata['rdef']["$contextpath:$roleid"]['mod/forum:viewpost'] = 1
94 * ['mod/forum:editallpost'] = -1
95 * ['mod/forum:startdiscussion'] = -1000
cc3edaa4 96 * </code>
92e53168 97 *
e922fe23 98 * See how has_capability_in_accessdata() walks up the tree.
92e53168 99 *
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100 * First we only load rdef and ra down to the course level, but not below.
101 * This keeps accessdata small and compact. Below-the-course ra/rdef
102 * are loaded as needed. We keep track of which courses we have loaded ra/rdef in
cc3edaa4 103 * <code>
e922fe23 104 * $accessdata['loaded'] = array($courseid1=>1, $courseid2=>1)
cc3edaa4 105 * </code>
92e53168 106 *
cc3edaa4 107 * <b>Stale accessdata</b>
92e53168 108 *
109 * For the logged-in user, accessdata is long-lived.
110 *
d867e696 111 * On each pageload we load $ACCESSLIB_PRIVATE->dirtycontexts which lists
92e53168 112 * context paths affected by changes. Any check at-or-below
113 * a dirty context will trigger a transparent reload of accessdata.
5a4e7398 114 *
4f65e0fb 115 * Changes at the system level will force the reload for everyone.
92e53168 116 *
cc3edaa4 117 * <b>Default role caps</b>
5a4e7398 118 * The default role assignment is not in the DB, so we
119 * add it manually to accessdata.
92e53168 120 *
121 * This means that functions that work directly off the
122 * DB need to ensure that the default role caps
5a4e7398 123 * are dealt with appropriately.
92e53168 124 *
f76249cc 125 * @package core_access
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126 * @copyright 1999 onwards Martin Dougiamas http://dougiamas.com
127 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
92e53168 128 */
bbbf2d40 129
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130defined('MOODLE_INTERNAL') || die();
131
e922fe23 132/** No capability change */
e49e61bf 133define('CAP_INHERIT', 0);
e922fe23 134/** Allow permission, overrides CAP_PREVENT defined in parent contexts */
bbbf2d40 135define('CAP_ALLOW', 1);
e922fe23 136/** Prevent permission, overrides CAP_ALLOW defined in parent contexts */
bbbf2d40 137define('CAP_PREVENT', -1);
e922fe23 138/** Prohibit permission, overrides everything in current and child contexts */
bbbf2d40 139define('CAP_PROHIBIT', -1000);
140
e922fe23 141/** System context level - only one instance in every system */
bbbf2d40 142define('CONTEXT_SYSTEM', 10);
e922fe23 143/** User context level - one instance for each user describing what others can do to user */
4b10f08b 144define('CONTEXT_USER', 30);
e922fe23 145/** Course category context level - one instance for each category */
bbbf2d40 146define('CONTEXT_COURSECAT', 40);
e922fe23 147/** Course context level - one instances for each course */
bbbf2d40 148define('CONTEXT_COURSE', 50);
e922fe23 149/** Course module context level - one instance for each course module */
bbbf2d40 150define('CONTEXT_MODULE', 70);
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151/**
152 * Block context level - one instance for each block, sticky blocks are tricky
153 * because ppl think they should be able to override them at lower contexts.
154 * Any other context level instance can be parent of block context.
155 */
bbbf2d40 156define('CONTEXT_BLOCK', 80);
157
e922fe23 158/** Capability allow management of trusts - NOT IMPLEMENTED YET - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
21b6db6e 159define('RISK_MANAGETRUST', 0x0001);
e922fe23 160/** Capability allows changes in system configuration - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
a6b02b65 161define('RISK_CONFIG', 0x0002);
f76249cc 162/** Capability allows user to add scripted content - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
21b6db6e 163define('RISK_XSS', 0x0004);
e922fe23 164/** Capability allows access to personal user information - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
21b6db6e 165define('RISK_PERSONAL', 0x0008);
f76249cc 166/** Capability allows users to add content others may see - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
21b6db6e 167define('RISK_SPAM', 0x0010);
e922fe23 168/** capability allows mass delete of data belonging to other users - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
3a0c6cca 169define('RISK_DATALOSS', 0x0020);
21b6db6e 170
c52551dc 171/** rolename displays - the name as defined in the role definition, localised if name empty */
cc3edaa4 172define('ROLENAME_ORIGINAL', 0);
c52551dc 173/** rolename displays - the name as defined by a role alias at the course level, falls back to ROLENAME_ORIGINAL if alias not present */
cc3edaa4 174define('ROLENAME_ALIAS', 1);
e922fe23 175/** rolename displays - Both, like this: Role alias (Original) */
cc3edaa4 176define('ROLENAME_BOTH', 2);
e922fe23 177/** rolename displays - the name as defined in the role definition and the shortname in brackets */
cc3edaa4 178define('ROLENAME_ORIGINALANDSHORT', 3);
e922fe23 179/** rolename displays - the name as defined by a role alias, in raw form suitable for editing */
cc3edaa4 180define('ROLENAME_ALIAS_RAW', 4);
e922fe23 181/** rolename displays - the name is simply short role name */
df997f84 182define('ROLENAME_SHORT', 5);
cc3edaa4 183
e922fe23 184if (!defined('CONTEXT_CACHE_MAX_SIZE')) {
f76249cc 185 /** maximum size of context cache - it is possible to tweak this config.php or in any script before inclusion of context.php */
e922fe23 186 define('CONTEXT_CACHE_MAX_SIZE', 2500);
4d10247f 187}
188
cc3edaa4 189/**
117bd748 190 * Although this looks like a global variable, it isn't really.
cc3edaa4 191 *
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192 * It is just a private implementation detail to accesslib that MUST NOT be used elsewhere.
193 * It is used to cache various bits of data between function calls for performance reasons.
4f65e0fb 194 * Sadly, a PHP global variable is the only way to implement this, without rewriting everything
cc3edaa4 195 * as methods of a class, instead of functions.
196 *
f76249cc 197 * @access private
cc3edaa4 198 * @global stdClass $ACCESSLIB_PRIVATE
199 * @name $ACCESSLIB_PRIVATE
200 */
f14438dc 201global $ACCESSLIB_PRIVATE;
62e65b21 202$ACCESSLIB_PRIVATE = new stdClass();
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203$ACCESSLIB_PRIVATE->dirtycontexts = null; // Dirty contexts cache, loaded from DB once per page
204$ACCESSLIB_PRIVATE->accessdatabyuser = array(); // Holds the cache of $accessdata structure for users (including $USER)
205$ACCESSLIB_PRIVATE->rolepermissions = array(); // role permissions cache - helps a lot with mem usage
206$ACCESSLIB_PRIVATE->capabilities = null; // detailed information about the capabilities
bbbf2d40 207
d867e696 208/**
46808d7c 209 * Clears accesslib's private caches. ONLY BE USED BY UNIT TESTS
117bd748 210 *
d867e696 211 * This method should ONLY BE USED BY UNIT TESTS. It clears all of
212 * accesslib's private caches. You need to do this before setting up test data,
4f65e0fb 213 * and also at the end of the tests.
e922fe23 214 *
f76249cc 215 * @access private
e922fe23 216 * @return void
d867e696 217 */
218function accesslib_clear_all_caches_for_unit_testing() {
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219 global $USER;
220 if (!PHPUNIT_TEST) {
d867e696 221 throw new coding_exception('You must not call clear_all_caches outside of unit tests.');
222 }
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223
224 accesslib_clear_all_caches(true);
d867e696 225
226 unset($USER->access);
227}
228
46808d7c 229/**
e922fe23 230 * Clears accesslib's private caches. ONLY BE USED FROM THIS LIBRARY FILE!
46808d7c 231 *
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232 * This reset does not touch global $USER.
233 *
f76249cc 234 * @access private
e922fe23
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235 * @param bool $resetcontexts
236 * @return void
46808d7c 237 */
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238function accesslib_clear_all_caches($resetcontexts) {
239 global $ACCESSLIB_PRIVATE;
e7876c1e 240
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241 $ACCESSLIB_PRIVATE->dirtycontexts = null;
242 $ACCESSLIB_PRIVATE->accessdatabyuser = array();
243 $ACCESSLIB_PRIVATE->rolepermissions = array();
244 $ACCESSLIB_PRIVATE->capabilities = null;
e7876c1e 245
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246 if ($resetcontexts) {
247 context_helper::reset_caches();
e7876c1e 248 }
eef879ec 249}
250
eef879ec 251/**
46808d7c 252 * Gets the accessdata for role "sitewide" (system down to course)
343effbe 253 *
f76249cc 254 * @access private
46808d7c 255 * @param int $roleid
e0376a62 256 * @return array
eef879ec 257 */
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258function get_role_access($roleid) {
259 global $DB, $ACCESSLIB_PRIVATE;
eef879ec 260
e922fe23 261 /* Get it in 1 DB query...
e0376a62 262 * - relevant role caps at the root and down
263 * to the course level - but not below
264 */
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265
266 //TODO: MUC - this could be cached in shared memory to speed up first page loading, web crawlers, etc.
267
268 $accessdata = get_empty_accessdata();
269
270 $accessdata['ra']['/'.SYSCONTEXTID] = array((int)$roleid => (int)$roleid);
e7876c1e 271
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272 // Overrides for the role IN ANY CONTEXTS down to COURSE - not below -.
273
274 /*
e0376a62 275 $sql = "SELECT ctx.path,
276 rc.capability, rc.permission
f33e1ed4 277 FROM {context} ctx
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278 JOIN {role_capabilities} rc ON rc.contextid = ctx.id
279 LEFT JOIN {context} cctx
280 ON (cctx.contextlevel = ".CONTEXT_COURSE." AND ctx.path LIKE ".$DB->sql_concat('cctx.path',"'/%'").")
281 WHERE rc.roleid = ? AND cctx.id IS NULL";
f33e1ed4 282 $params = array($roleid);
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283 */
284
285 // Note: the commented out query is 100% accurate but slow, so let's cheat instead by hardcoding the blocks mess directly.
286
287 $sql = "SELECT COALESCE(ctx.path, bctx.path) AS path, rc.capability, rc.permission
288 FROM {role_capabilities} rc
289 LEFT JOIN {context} ctx ON (ctx.id = rc.contextid AND ctx.contextlevel <= ".CONTEXT_COURSE.")
290 LEFT JOIN ({context} bctx
291 JOIN {block_instances} bi ON (bi.id = bctx.instanceid)
292 JOIN {context} pctx ON (pctx.id = bi.parentcontextid AND pctx.contextlevel < ".CONTEXT_COURSE.")
293 ) ON (bctx.id = rc.contextid AND bctx.contextlevel = ".CONTEXT_BLOCK.")
294 WHERE rc.roleid = :roleid AND (ctx.id IS NOT NULL OR bctx.id IS NOT NULL)";
295 $params = array('roleid'=>$roleid);
133d5a97 296
a91b910e 297 // we need extra caching in CLI scripts and cron
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298 $rs = $DB->get_recordset_sql($sql, $params);
299 foreach ($rs as $rd) {
300 $k = "{$rd->path}:{$roleid}";
301 $accessdata['rdef'][$k][$rd->capability] = (int)$rd->permission;
8d2b18a8 302 }
e922fe23 303 $rs->close();
e0376a62 304
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305 // share the role definitions
306 foreach ($accessdata['rdef'] as $k=>$unused) {
307 if (!isset($ACCESSLIB_PRIVATE->rolepermissions[$k])) {
308 $ACCESSLIB_PRIVATE->rolepermissions[$k] = $accessdata['rdef'][$k];
4e1fe7d1 309 }
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310 $accessdata['rdef_count']++;
311 $accessdata['rdef'][$k] =& $ACCESSLIB_PRIVATE->rolepermissions[$k];
4e1fe7d1 312 }
313
314 return $accessdata;
315}
316
8f8ed475 317/**
e922fe23
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318 * Get the default guest role, this is used for guest account,
319 * search engine spiders, etc.
117bd748 320 *
e922fe23 321 * @return stdClass role record
8f8ed475 322 */
323function get_guest_role() {
f33e1ed4 324 global $CFG, $DB;
ebce32b5 325
326 if (empty($CFG->guestroleid)) {
4f0c2d00 327 if ($roles = $DB->get_records('role', array('archetype'=>'guest'))) {
ebce32b5 328 $guestrole = array_shift($roles); // Pick the first one
329 set_config('guestroleid', $guestrole->id);
330 return $guestrole;
331 } else {
332 debugging('Can not find any guest role!');
333 return false;
334 }
8f8ed475 335 } else {
f33e1ed4 336 if ($guestrole = $DB->get_record('role', array('id'=>$CFG->guestroleid))) {
ebce32b5 337 return $guestrole;
338 } else {
e922fe23 339 // somebody is messing with guest roles, remove incorrect setting and try to find a new one
ebce32b5 340 set_config('guestroleid', '');
341 return get_guest_role();
342 }
8f8ed475 343 }
344}
345
128f0984 346/**
4f65e0fb 347 * Check whether a user has a particular capability in a given context.
46808d7c 348 *
e922fe23 349 * For example:
f76249cc
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350 * $context = context_module::instance($cm->id);
351 * has_capability('mod/forum:replypost', $context)
46808d7c 352 *
4f65e0fb 353 * By default checks the capabilities of the current user, but you can pass a
4f0c2d00
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354 * different userid. By default will return true for admin users, but you can override that with the fourth argument.
355 *
356 * Guest and not-logged-in users can never get any dangerous capability - that is any write capability
357 * or capabilities with XSS, config or data loss risks.
117bd748 358 *
f76249cc
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359 * @category access
360 *
41e87d30 361 * @param string $capability the name of the capability to check. For example mod/forum:view
f76249cc
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362 * @param context $context the context to check the capability in. You normally get this with instance method of a context class.
363 * @param integer|stdClass $user A user id or object. By default (null) checks the permissions of the current user.
4f0c2d00 364 * @param boolean $doanything If false, ignores effect of admin role assignment
41e87d30 365 * @return boolean true if the user has this capability. Otherwise false.
128f0984 366 */
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367function has_capability($capability, context $context, $user = null, $doanything = true) {
368 global $USER, $CFG, $SCRIPT, $ACCESSLIB_PRIVATE;
18818abf 369
31a99877 370 if (during_initial_install()) {
e922fe23 371 if ($SCRIPT === "/$CFG->admin/index.php" or $SCRIPT === "/$CFG->admin/cli/install.php" or $SCRIPT === "/$CFG->admin/cli/install_database.php") {
18818abf 372 // we are in an installer - roles can not work yet
373 return true;
374 } else {
375 return false;
376 }
377 }
7f97ea29 378
4f0c2d00
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379 if (strpos($capability, 'moodle/legacy:') === 0) {
380 throw new coding_exception('Legacy capabilities can not be used any more!');
381 }
382
e922fe23
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383 if (!is_bool($doanything)) {
384 throw new coding_exception('Capability parameter "doanything" is wierd, only true or false is allowed. This has to be fixed in code.');
385 }
386
387 // capability must exist
388 if (!$capinfo = get_capability_info($capability)) {
389 debugging('Capability "'.$capability.'" was not found! This has to be fixed in code.');
7d0c81b3 390 return false;
74ac5b66 391 }
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392
393 if (!isset($USER->id)) {
394 // should never happen
395 $USER->id = 0;
c90e6b46 396 debugging('Capability check being performed on a user with no ID.', DEBUG_DEVELOPER);
4f0c2d00 397 }
7f97ea29 398
4f0c2d00 399 // make sure there is a real user specified
62e65b21 400 if ($user === null) {
e922fe23 401 $userid = $USER->id;
4f0c2d00 402 } else {
2b55aca7 403 $userid = is_object($user) ? $user->id : $user;
cc3d5e10 404 }
405
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406 // make sure forcelogin cuts off not-logged-in users if enabled
407 if (!empty($CFG->forcelogin) and $userid == 0) {
4f0c2d00
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408 return false;
409 }
e922fe23 410
4f0c2d00 411 // make sure the guest account and not-logged-in users never get any risky caps no matter what the actual settings are.
e922fe23 412 if (($capinfo->captype === 'write') or ($capinfo->riskbitmask & (RISK_XSS | RISK_CONFIG | RISK_DATALOSS))) {
4f0c2d00
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413 if (isguestuser($userid) or $userid == 0) {
414 return false;
c84a2dbe 415 }
7f97ea29 416 }
417
e922fe23
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418 // somehow make sure the user is not deleted and actually exists
419 if ($userid != 0) {
420 if ($userid == $USER->id and isset($USER->deleted)) {
421 // this prevents one query per page, it is a bit of cheating,
422 // but hopefully session is terminated properly once user is deleted
423 if ($USER->deleted) {
424 return false;
425 }
128f0984 426 } else {
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427 if (!context_user::instance($userid, IGNORE_MISSING)) {
428 // no user context == invalid userid
429 return false;
430 }
7be3be1b 431 }
148eb2a7 432 }
128f0984 433
e922fe23
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434 // context path/depth must be valid
435 if (empty($context->path) or $context->depth == 0) {
436 // this should not happen often, each upgrade tries to rebuild the context paths
437 debugging('Context id '.$context->id.' does not have valid path, please use build_context_path()');
438 if (is_siteadmin($userid)) {
439 return true;
128f0984 440 } else {
e922fe23 441 return false;
128f0984 442 }
148eb2a7 443 }
128f0984 444
4f0c2d00
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445 // Find out if user is admin - it is not possible to override the doanything in any way
446 // and it is not possible to switch to admin role either.
447 if ($doanything) {
448 if (is_siteadmin($userid)) {
7abbc5c2
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449 if ($userid != $USER->id) {
450 return true;
451 }
452 // make sure switchrole is not used in this context
453 if (empty($USER->access['rsw'])) {
454 return true;
455 }
456 $parts = explode('/', trim($context->path, '/'));
457 $path = '';
458 $switched = false;
459 foreach ($parts as $part) {
460 $path .= '/' . $part;
461 if (!empty($USER->access['rsw'][$path])) {
462 $switched = true;
463 break;
464 }
465 }
466 if (!$switched) {
467 return true;
468 }
469 //ok, admin switched role in this context, let's use normal access control rules
4f0c2d00
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470 }
471 }
472
e922fe23
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473 // Careful check for staleness...
474 $context->reload_if_dirty();
13a79475 475
e922fe23
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476 if ($USER->id == $userid) {
477 if (!isset($USER->access)) {
478 load_all_capabilities();
7f97ea29 479 }
e922fe23 480 $access =& $USER->access;
bb2c22bd 481
e922fe23
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482 } else {
483 // make sure user accessdata is really loaded
484 get_user_accessdata($userid, true);
485 $access =& $ACCESSLIB_PRIVATE->accessdatabyuser[$userid];
204a369c 486 }
4f0c2d00 487
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488
489 // Load accessdata for below-the-course context if necessary,
490 // all contexts at and above all courses are already loaded
491 if ($context->contextlevel != CONTEXT_COURSE and $coursecontext = $context->get_course_context(false)) {
492 load_course_context($userid, $coursecontext, $access);
420bfab1 493 }
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494
495 return has_capability_in_accessdata($capability, $context, $access);
7f97ea29 496}
497
3fc3ebf2 498/**
41e87d30 499 * Check if the user has any one of several capabilities from a list.
46808d7c 500 *
41e87d30 501 * This is just a utility method that calls has_capability in a loop. Try to put
502 * the capabilities that most users are likely to have first in the list for best
503 * performance.
3fc3ebf2 504 *
f76249cc 505 * @category access
46808d7c 506 * @see has_capability()
f76249cc 507 *
41e87d30 508 * @param array $capabilities an array of capability names.
f76249cc
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509 * @param context $context the context to check the capability in. You normally get this with instance method of a context class.
510 * @param integer|stdClass $user A user id or object. By default (null) checks the permissions of the current user.
4f0c2d00 511 * @param boolean $doanything If false, ignore effect of admin role assignment
41e87d30 512 * @return boolean true if the user has any of these capabilities. Otherwise false.
3fc3ebf2 513 */
f76249cc 514function has_any_capability(array $capabilities, context $context, $user = null, $doanything = true) {
3fc3ebf2 515 foreach ($capabilities as $capability) {
f76249cc 516 if (has_capability($capability, $context, $user, $doanything)) {
3fc3ebf2 517 return true;
518 }
519 }
520 return false;
521}
522
8a1b1c32 523/**
41e87d30 524 * Check if the user has all the capabilities in a list.
46808d7c 525 *
41e87d30 526 * This is just a utility method that calls has_capability in a loop. Try to put
527 * the capabilities that fewest users are likely to have first in the list for best
528 * performance.
8a1b1c32 529 *
f76249cc 530 * @category access
46808d7c 531 * @see has_capability()
f76249cc 532 *
41e87d30 533 * @param array $capabilities an array of capability names.
f76249cc
PS
534 * @param context $context the context to check the capability in. You normally get this with instance method of a context class.
535 * @param integer|stdClass $user A user id or object. By default (null) checks the permissions of the current user.
4f0c2d00 536 * @param boolean $doanything If false, ignore effect of admin role assignment
41e87d30 537 * @return boolean true if the user has all of these capabilities. Otherwise false.
8a1b1c32 538 */
f76249cc 539function has_all_capabilities(array $capabilities, context $context, $user = null, $doanything = true) {
8a1b1c32 540 foreach ($capabilities as $capability) {
f76249cc 541 if (!has_capability($capability, $context, $user, $doanything)) {
8a1b1c32 542 return false;
543 }
544 }
545 return true;
546}
547
a56ec918
PS
548/**
549 * Is course creator going to have capability in a new course?
550 *
551 * This is intended to be used in enrolment plugins before or during course creation,
552 * do not use after the course is fully created.
553 *
554 * @category access
555 *
556 * @param string $capability the name of the capability to check.
557 * @param context $context course or category context where is course going to be created
558 * @param integer|stdClass $user A user id or object. By default (null) checks the permissions of the current user.
559 * @return boolean true if the user will have this capability.
560 *
c6f5e84f 561 * @throws coding_exception if different type of context submitted
a56ec918 562 */
54d5308e 563function guess_if_creator_will_have_course_capability($capability, context $context, $user = null) {
a56ec918
PS
564 global $CFG;
565
566 if ($context->contextlevel != CONTEXT_COURSE and $context->contextlevel != CONTEXT_COURSECAT) {
567 throw new coding_exception('Only course or course category context expected');
568 }
569
570 if (has_capability($capability, $context, $user)) {
571 // User already has the capability, it could be only removed if CAP_PROHIBIT
572 // was involved here, but we ignore that.
573 return true;
574 }
575
576 if (!has_capability('moodle/course:create', $context, $user)) {
577 return false;
578 }
579
580 if (!enrol_is_enabled('manual')) {
581 return false;
582 }
583
584 if (empty($CFG->creatornewroleid)) {
585 return false;
586 }
587
588 if ($context->contextlevel == CONTEXT_COURSE) {
589 if (is_viewing($context, $user, 'moodle/role:assign') or is_enrolled($context, $user, 'moodle/role:assign')) {
590 return false;
591 }
592 } else {
593 if (has_capability('moodle/course:view', $context, $user) and has_capability('moodle/role:assign', $context, $user)) {
594 return false;
595 }
596 }
597
598 // Most likely they will be enrolled after the course creation is finished,
599 // does the new role have the required capability?
600 list($neededroles, $forbiddenroles) = get_roles_with_cap_in_context($context, $capability);
601 return isset($neededroles[$CFG->creatornewroleid]);
602}
603
128f0984 604/**
4f0c2d00 605 * Check if the user is an admin at the site level.
46808d7c 606 *
4f0c2d00
PS
607 * Please note that use of proper capabilities is always encouraged,
608 * this function is supposed to be used from core or for temporary hacks.
39407442 609 *
f76249cc
PS
610 * @category access
611 *
e922fe23
PS
612 * @param int|stdClass $user_or_id user id or user object
613 * @return bool true if user is one of the administrators, false otherwise
39407442 614 */
62e65b21 615function is_siteadmin($user_or_id = null) {
4f0c2d00 616 global $CFG, $USER;
39407442 617
62e65b21 618 if ($user_or_id === null) {
4f0c2d00
PS
619 $user_or_id = $USER;
620 }
6cab02ac 621
4f0c2d00
PS
622 if (empty($user_or_id)) {
623 return false;
624 }
625 if (!empty($user_or_id->id)) {
4f0c2d00
PS
626 $userid = $user_or_id->id;
627 } else {
628 $userid = $user_or_id;
629 }
6cab02ac 630
0d9e5992 631 // Because this script is called many times (150+ for course page) with
632 // the same parameters, it is worth doing minor optimisations. This static
633 // cache stores the value for a single userid, saving about 2ms from course
634 // page load time without using significant memory. As the static cache
635 // also includes the value it depends on, this cannot break unit tests.
636 static $knownid, $knownresult, $knownsiteadmins;
637 if ($knownid === $userid && $knownsiteadmins === $CFG->siteadmins) {
638 return $knownresult;
639 }
640 $knownid = $userid;
641 $knownsiteadmins = $CFG->siteadmins;
642
4f0c2d00 643 $siteadmins = explode(',', $CFG->siteadmins);
0d9e5992 644 $knownresult = in_array($userid, $siteadmins);
645 return $knownresult;
6cab02ac 646}
647
bbdb7070 648/**
4f0c2d00 649 * Returns true if user has at least one role assign
df997f84 650 * of 'coursecontact' role (is potentially listed in some course descriptions).
62e65b21 651 *
e922fe23
PS
652 * @param int $userid
653 * @return bool
bbdb7070 654 */
df997f84 655function has_coursecontact_role($userid) {
2fb34345 656 global $DB, $CFG;
bbdb7070 657
df997f84 658 if (empty($CFG->coursecontact)) {
4f0c2d00
PS
659 return false;
660 }
661 $sql = "SELECT 1
662 FROM {role_assignments}
df997f84 663 WHERE userid = :userid AND roleid IN ($CFG->coursecontact)";
b2cd6570 664 return $DB->record_exists_sql($sql, array('userid'=>$userid));
bbdb7070 665}
666
128f0984 667/**
01a2ce80 668 * Does the user have a capability to do something?
46808d7c 669 *
31c2de82 670 * Walk the accessdata array and return true/false.
e922fe23 671 * Deals with prohibits, role switching, aggregating
6a8d9a38 672 * capabilities, etc.
673 *
674 * The main feature of here is being FAST and with no
5a4e7398 675 * side effects.
6a8d9a38 676 *
3ac81bd1 677 * Notes:
678 *
3d034f77 679 * Switch Role merges with default role
680 * ------------------------------------
681 * If you are a teacher in course X, you have at least
682 * teacher-in-X + defaultloggedinuser-sitewide. So in the
683 * course you'll have techer+defaultloggedinuser.
684 * We try to mimic that in switchrole.
685 *
01a2ce80
PS
686 * Permission evaluation
687 * ---------------------
4f65e0fb 688 * Originally there was an extremely complicated way
01a2ce80 689 * to determine the user access that dealt with
4f65e0fb
PS
690 * "locality" or role assignments and role overrides.
691 * Now we simply evaluate access for each role separately
01a2ce80
PS
692 * and then verify if user has at least one role with allow
693 * and at the same time no role with prohibit.
694 *
f76249cc 695 * @access private
46808d7c 696 * @param string $capability
e922fe23 697 * @param context $context
46808d7c 698 * @param array $accessdata
46808d7c 699 * @return bool
6a8d9a38 700 */
e922fe23 701function has_capability_in_accessdata($capability, context $context, array &$accessdata) {
3ac81bd1 702 global $CFG;
703
01a2ce80 704 // Build $paths as a list of current + all parent "paths" with order bottom-to-top
e922fe23
PS
705 $path = $context->path;
706 $paths = array($path);
707 while($path = rtrim($path, '0123456789')) {
708 $path = rtrim($path, '/');
709 if ($path === '') {
710 break;
711 }
712 $paths[] = $path;
3ac81bd1 713 }
714
01a2ce80
PS
715 $roles = array();
716 $switchedrole = false;
6a8d9a38 717
01a2ce80
PS
718 // Find out if role switched
719 if (!empty($accessdata['rsw'])) {
6a8d9a38 720 // From the bottom up...
01a2ce80 721 foreach ($paths as $path) {
1209cb5c 722 if (isset($accessdata['rsw'][$path])) {
01a2ce80 723 // Found a switchrole assignment - check for that role _plus_ the default user role
62e65b21 724 $roles = array($accessdata['rsw'][$path]=>null, $CFG->defaultuserroleid=>null);
01a2ce80
PS
725 $switchedrole = true;
726 break;
6a8d9a38 727 }
728 }
729 }
730
01a2ce80
PS
731 if (!$switchedrole) {
732 // get all users roles in this context and above
733 foreach ($paths as $path) {
734 if (isset($accessdata['ra'][$path])) {
735 foreach ($accessdata['ra'][$path] as $roleid) {
62e65b21 736 $roles[$roleid] = null;
7f97ea29 737 }
01a2ce80
PS
738 }
739 }
7f97ea29 740 }
741
01a2ce80 742 // Now find out what access is given to each role, going bottom-->up direction
e922fe23 743 $allowed = false;
01a2ce80
PS
744 foreach ($roles as $roleid => $ignored) {
745 foreach ($paths as $path) {
746 if (isset($accessdata['rdef']["{$path}:$roleid"][$capability])) {
747 $perm = (int)$accessdata['rdef']["{$path}:$roleid"][$capability];
e922fe23
PS
748 if ($perm === CAP_PROHIBIT) {
749 // any CAP_PROHIBIT found means no permission for the user
750 return false;
751 }
752 if (is_null($roles[$roleid])) {
01a2ce80
PS
753 $roles[$roleid] = $perm;
754 }
755 }
7f97ea29 756 }
e922fe23
PS
757 // CAP_ALLOW in any role means the user has a permission, we continue only to detect prohibits
758 $allowed = ($allowed or $roles[$roleid] === CAP_ALLOW);
7f97ea29 759 }
760
e922fe23 761 return $allowed;
018d4b52 762}
763
0468976c 764/**
41e87d30 765 * A convenience function that tests has_capability, and displays an error if
766 * the user does not have that capability.
8a9c1c1c 767 *
41e87d30 768 * NOTE before Moodle 2.0, this function attempted to make an appropriate
769 * require_login call before checking the capability. This is no longer the case.
770 * You must call require_login (or one of its variants) if you want to check the
771 * user is logged in, before you call this function.
efd6fce5 772 *
46808d7c 773 * @see has_capability()
774 *
41e87d30 775 * @param string $capability the name of the capability to check. For example mod/forum:view
bea86e84 776 * @param context $context the context to check the capability in. You normally get this with context_xxxx::instance().
e922fe23 777 * @param int $userid A user id. By default (null) checks the permissions of the current user.
4f0c2d00 778 * @param bool $doanything If false, ignore effect of admin role assignment
e922fe23 779 * @param string $errormessage The error string to to user. Defaults to 'nopermissions'.
41e87d30 780 * @param string $stringfile The language file to load the error string from. Defaults to 'error'.
781 * @return void terminates with an error if the user does not have the given capability.
0468976c 782 */
e922fe23 783function require_capability($capability, context $context, $userid = null, $doanything = true,
41e87d30 784 $errormessage = 'nopermissions', $stringfile = '') {
d74067e8 785 if (!has_capability($capability, $context, $userid, $doanything)) {
9a0df45a 786 throw new required_capability_exception($context, $capability, $errormessage, $stringfile);
0468976c 787 }
788}
789
a9bee37e 790/**
46808d7c 791 * Return a nested array showing role assignments
a9bee37e 792 * all relevant role capabilities for the user at
df997f84 793 * site/course_category/course levels
a9bee37e 794 *
795 * We do _not_ delve deeper than courses because the number of
e922fe23 796 * overrides at the module/block levels can be HUGE.
a9bee37e 797 *
e922fe23
PS
798 * [ra] => [/path][roleid]=roleid
799 * [rdef] => [/path:roleid][capability]=permission
a9bee37e 800 *
f76249cc 801 * @access private
62e65b21 802 * @param int $userid - the id of the user
e922fe23 803 * @return array access info array
a9bee37e 804 */
74ac5b66 805function get_user_access_sitewide($userid) {
e922fe23 806 global $CFG, $DB, $ACCESSLIB_PRIVATE;
a9bee37e 807
e922fe23 808 /* Get in a few cheap DB queries...
f5930992 809 * - role assignments
a9bee37e 810 * - relevant role caps
f5930992 811 * - above and within this user's RAs
a9bee37e 812 * - below this user's RAs - limited to course level
813 */
814
e922fe23
PS
815 // raparents collects paths & roles we need to walk up the parenthood to build the minimal rdef
816 $raparents = array();
817 $accessdata = get_empty_accessdata();
a9bee37e 818
e922fe23
PS
819 // start with the default role
820 if (!empty($CFG->defaultuserroleid)) {
821 $syscontext = context_system::instance();
822 $accessdata['ra'][$syscontext->path][(int)$CFG->defaultuserroleid] = (int)$CFG->defaultuserroleid;
e7f2c2cc 823 $raparents[$CFG->defaultuserroleid][$syscontext->id] = $syscontext->id;
e922fe23
PS
824 }
825
826 // load the "default frontpage role"
827 if (!empty($CFG->defaultfrontpageroleid)) {
828 $frontpagecontext = context_course::instance(get_site()->id);
829 if ($frontpagecontext->path) {
830 $accessdata['ra'][$frontpagecontext->path][(int)$CFG->defaultfrontpageroleid] = (int)$CFG->defaultfrontpageroleid;
e7f2c2cc 831 $raparents[$CFG->defaultfrontpageroleid][$frontpagecontext->id] = $frontpagecontext->id;
e922fe23
PS
832 }
833 }
834
835 // preload every assigned role at and above course context
e7f2c2cc 836 $sql = "SELECT ctx.path, ra.roleid, ra.contextid
f33e1ed4 837 FROM {role_assignments} ra
e7f2c2cc
PS
838 JOIN {context} ctx
839 ON ctx.id = ra.contextid
840 LEFT JOIN {block_instances} bi
841 ON (ctx.contextlevel = ".CONTEXT_BLOCK." AND bi.id = ctx.instanceid)
842 LEFT JOIN {context} bpctx
843 ON (bpctx.id = bi.parentcontextid)
844 WHERE ra.userid = :userid
845 AND (ctx.contextlevel <= ".CONTEXT_COURSE." OR bpctx.contextlevel < ".CONTEXT_COURSE.")";
e922fe23
PS
846 $params = array('userid'=>$userid);
847 $rs = $DB->get_recordset_sql($sql, $params);
848 foreach ($rs as $ra) {
849 // RAs leafs are arrays to support multi-role assignments...
850 $accessdata['ra'][$ra->path][(int)$ra->roleid] = (int)$ra->roleid;
e7f2c2cc 851 $raparents[$ra->roleid][$ra->contextid] = $ra->contextid;
a9bee37e 852 }
e922fe23 853 $rs->close();
a9bee37e 854
e922fe23
PS
855 if (empty($raparents)) {
856 return $accessdata;
a9bee37e 857 }
f5930992 858
e922fe23
PS
859 // now get overrides of interesting roles in all interesting child contexts
860 // hopefully we will not run out of SQL limits here,
e7f2c2cc 861 // users would have to have very many roles at/above course context...
e922fe23
PS
862 $sqls = array();
863 $params = array();
f5930992 864
e922fe23 865 static $cp = 0;
e7f2c2cc 866 foreach ($raparents as $roleid=>$ras) {
e922fe23 867 $cp++;
e7f2c2cc
PS
868 list($sqlcids, $cids) = $DB->get_in_or_equal($ras, SQL_PARAMS_NAMED, 'c'.$cp.'_');
869 $params = array_merge($params, $cids);
e922fe23
PS
870 $params['r'.$cp] = $roleid;
871 $sqls[] = "(SELECT ctx.path, rc.roleid, rc.capability, rc.permission
872 FROM {role_capabilities} rc
873 JOIN {context} ctx
874 ON (ctx.id = rc.contextid)
e922fe23 875 JOIN {context} pctx
e7f2c2cc 876 ON (pctx.id $sqlcids
e922fe23
PS
877 AND (ctx.id = pctx.id
878 OR ctx.path LIKE ".$DB->sql_concat('pctx.path',"'/%'")."
879 OR pctx.path LIKE ".$DB->sql_concat('ctx.path',"'/%'")."))
e7f2c2cc
PS
880 LEFT JOIN {block_instances} bi
881 ON (ctx.contextlevel = ".CONTEXT_BLOCK." AND bi.id = ctx.instanceid)
882 LEFT JOIN {context} bpctx
883 ON (bpctx.id = bi.parentcontextid)
e922fe23 884 WHERE rc.roleid = :r{$cp}
e7f2c2cc
PS
885 AND (ctx.contextlevel <= ".CONTEXT_COURSE." OR bpctx.contextlevel < ".CONTEXT_COURSE.")
886 )";
e922fe23
PS
887 }
888
889 // fixed capability order is necessary for rdef dedupe
890 $rs = $DB->get_recordset_sql(implode("\nUNION\n", $sqls). "ORDER BY capability", $params);
a9bee37e 891
e922fe23
PS
892 foreach ($rs as $rd) {
893 $k = $rd->path.':'.$rd->roleid;
894 $accessdata['rdef'][$k][$rd->capability] = (int)$rd->permission;
a9bee37e 895 }
e922fe23 896 $rs->close();
a9bee37e 897
e922fe23
PS
898 // share the role definitions
899 foreach ($accessdata['rdef'] as $k=>$unused) {
900 if (!isset($ACCESSLIB_PRIVATE->rolepermissions[$k])) {
901 $ACCESSLIB_PRIVATE->rolepermissions[$k] = $accessdata['rdef'][$k];
0dbb2191 902 }
e922fe23
PS
903 $accessdata['rdef_count']++;
904 $accessdata['rdef'][$k] =& $ACCESSLIB_PRIVATE->rolepermissions[$k];
a9bee37e 905 }
e922fe23 906
bb2c22bd 907 return $accessdata;
a9bee37e 908}
909
74ac5b66 910/**
e922fe23 911 * Add to the access ctrl array the data needed by a user for a given course.
74ac5b66 912 *
e922fe23
PS
913 * This function injects all course related access info into the accessdata array.
914 *
f76249cc 915 * @access private
e922fe23
PS
916 * @param int $userid the id of the user
917 * @param context_course $coursecontext course context
918 * @param array $accessdata accessdata array (modified)
919 * @return void modifies $accessdata parameter
74ac5b66 920 */
e922fe23
PS
921function load_course_context($userid, context_course $coursecontext, &$accessdata) {
922 global $DB, $CFG, $ACCESSLIB_PRIVATE;
018d4b52 923
e922fe23
PS
924 if (empty($coursecontext->path)) {
925 // weird, this should not happen
926 return;
927 }
74ac5b66 928
e922fe23
PS
929 if (isset($accessdata['loaded'][$coursecontext->instanceid])) {
930 // already loaded, great!
931 return;
932 }
74ac5b66 933
e922fe23 934 $roles = array();
5a4e7398 935
e922fe23
PS
936 if (empty($userid)) {
937 if (!empty($CFG->notloggedinroleid)) {
938 $roles[$CFG->notloggedinroleid] = $CFG->notloggedinroleid;
939 }
74ac5b66 940
e922fe23
PS
941 } else if (isguestuser($userid)) {
942 if ($guestrole = get_guest_role()) {
943 $roles[$guestrole->id] = $guestrole->id;
944 }
74ac5b66 945
e922fe23
PS
946 } else {
947 // Interesting role assignments at, above and below the course context
948 list($parentsaself, $params) = $DB->get_in_or_equal($coursecontext->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'pc_');
949 $params['userid'] = $userid;
950 $params['children'] = $coursecontext->path."/%";
951 $sql = "SELECT ra.*, ctx.path
952 FROM {role_assignments} ra
953 JOIN {context} ctx ON ra.contextid = ctx.id
954 WHERE ra.userid = :userid AND (ctx.id $parentsaself OR ctx.path LIKE :children)";
955 $rs = $DB->get_recordset_sql($sql, $params);
956
957 // add missing role definitions
f33e1ed4 958 foreach ($rs as $ra) {
e922fe23
PS
959 $accessdata['ra'][$ra->path][(int)$ra->roleid] = (int)$ra->roleid;
960 $roles[$ra->roleid] = $ra->roleid;
74ac5b66 961 }
f33e1ed4 962 $rs->close();
74ac5b66 963
e922fe23
PS
964 // add the "default frontpage role" when on the frontpage
965 if (!empty($CFG->defaultfrontpageroleid)) {
966 $frontpagecontext = context_course::instance(get_site()->id);
967 if ($frontpagecontext->id == $coursecontext->id) {
968 $roles[$CFG->defaultfrontpageroleid] = $CFG->defaultfrontpageroleid;
969 }
970 }
53fb75dc 971
e922fe23
PS
972 // do not forget the default role
973 if (!empty($CFG->defaultuserroleid)) {
974 $roles[$CFG->defaultuserroleid] = $CFG->defaultuserroleid;
975 }
74ac5b66 976 }
977
e922fe23
PS
978 if (!$roles) {
979 // weird, default roles must be missing...
980 $accessdata['loaded'][$coursecontext->instanceid] = 1;
981 return;
7e17f43b 982 }
e922fe23
PS
983
984 // now get overrides of interesting roles in all interesting contexts (this course + children + parents)
985 $params = array('c'=>$coursecontext->id);
986 list($parentsaself, $rparams) = $DB->get_in_or_equal($coursecontext->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'pc_');
987 $params = array_merge($params, $rparams);
988 list($roleids, $rparams) = $DB->get_in_or_equal($roles, SQL_PARAMS_NAMED, 'r_');
989 $params = array_merge($params, $rparams);
990
53fb75dc 991 $sql = "SELECT ctx.path, rc.roleid, rc.capability, rc.permission
e922fe23
PS
992 FROM {role_capabilities} rc
993 JOIN {context} ctx
994 ON (ctx.id = rc.contextid)
995 JOIN {context} cctx
996 ON (cctx.id = :c
997 AND (ctx.id $parentsaself OR ctx.path LIKE ".$DB->sql_concat('cctx.path',"'/%'")."))
998 WHERE rc.roleid $roleids
999 ORDER BY rc.capability"; // fixed capability order is necessary for rdef dedupe
1000 $rs = $DB->get_recordset_sql($sql, $params);
53fb75dc 1001
a2cf7f1b 1002 $newrdefs = array();
afa559e9 1003 foreach ($rs as $rd) {
e922fe23
PS
1004 $k = $rd->path.':'.$rd->roleid;
1005 if (isset($accessdata['rdef'][$k])) {
1006 continue;
74ac5b66 1007 }
e922fe23 1008 $newrdefs[$k][$rd->capability] = (int)$rd->permission;
74ac5b66 1009 }
afa559e9 1010 $rs->close();
74ac5b66 1011
e922fe23
PS
1012 // share new role definitions
1013 foreach ($newrdefs as $k=>$unused) {
1014 if (!isset($ACCESSLIB_PRIVATE->rolepermissions[$k])) {
1015 $ACCESSLIB_PRIVATE->rolepermissions[$k] = $newrdefs[$k];
1016 }
1017 $accessdata['rdef_count']++;
1018 $accessdata['rdef'][$k] =& $ACCESSLIB_PRIVATE->rolepermissions[$k];
a2cf7f1b 1019 }
74ac5b66 1020
e922fe23
PS
1021 $accessdata['loaded'][$coursecontext->instanceid] = 1;
1022
1023 // we want to deduplicate the USER->access from time to time, this looks like a good place,
1024 // because we have to do it before the end of session
1025 dedupe_user_access();
74ac5b66 1026}
2f1a4248 1027
eef879ec 1028/**
46808d7c 1029 * Add to the access ctrl array the data needed by a role for a given context.
6f1bce30 1030 *
1031 * The data is added in the rdef key.
6f1bce30 1032 * This role-centric function is useful for role_switching
e922fe23 1033 * and temporary course roles.
6f1bce30 1034 *
f76249cc 1035 * @access private
e922fe23
PS
1036 * @param int $roleid the id of the user
1037 * @param context $context needs path!
1038 * @param array $accessdata accessdata array (is modified)
46808d7c 1039 * @return array
6f1bce30 1040 */
e922fe23
PS
1041function load_role_access_by_context($roleid, context $context, &$accessdata) {
1042 global $DB, $ACCESSLIB_PRIVATE;
6f1bce30 1043
1044 /* Get the relevant rolecaps into rdef
1045 * - relevant role caps
1046 * - at ctx and above
1047 * - below this ctx
1048 */
1049
e922fe23
PS
1050 if (empty($context->path)) {
1051 // weird, this should not happen
1052 return;
6f1bce30 1053 }
5a4e7398 1054
e922fe23
PS
1055 list($parentsaself, $params) = $DB->get_in_or_equal($context->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'pc_');
1056 $params['roleid'] = $roleid;
1057 $params['childpath'] = $context->path.'/%';
6f1bce30 1058
6f1bce30 1059 $sql = "SELECT ctx.path, rc.capability, rc.permission
f33e1ed4 1060 FROM {role_capabilities} rc
e922fe23
PS
1061 JOIN {context} ctx ON (rc.contextid = ctx.id)
1062 WHERE rc.roleid = :roleid AND (ctx.id $parentsaself OR ctx.path LIKE :childpath)
1063 ORDER BY rc.capability"; // fixed capability order is necessary for rdef dedupe
afa559e9 1064 $rs = $DB->get_recordset_sql($sql, $params);
e922fe23
PS
1065
1066 $newrdefs = array();
afa559e9 1067 foreach ($rs as $rd) {
e922fe23
PS
1068 $k = $rd->path.':'.$roleid;
1069 if (isset($accessdata['rdef'][$k])) {
1070 continue;
1071 }
1072 $newrdefs[$k][$rd->capability] = (int)$rd->permission;
6f1bce30 1073 }
afa559e9 1074 $rs->close();
6f1bce30 1075
e922fe23
PS
1076 // share new role definitions
1077 foreach ($newrdefs as $k=>$unused) {
1078 if (!isset($ACCESSLIB_PRIVATE->rolepermissions[$k])) {
1079 $ACCESSLIB_PRIVATE->rolepermissions[$k] = $newrdefs[$k];
1080 }
1081 $accessdata['rdef_count']++;
1082 $accessdata['rdef'][$k] =& $ACCESSLIB_PRIVATE->rolepermissions[$k];
1083 }
1084}
1085
1086/**
1087 * Returns empty accessdata structure.
99ddfdf4 1088 *
f76249cc 1089 * @access private
e922fe23
PS
1090 * @return array empt accessdata
1091 */
1092function get_empty_accessdata() {
1093 $accessdata = array(); // named list
1094 $accessdata['ra'] = array();
1095 $accessdata['rdef'] = array();
1096 $accessdata['rdef_count'] = 0; // this bloody hack is necessary because count($array) is slooooowwww in PHP
1097 $accessdata['rdef_lcc'] = 0; // rdef_count during the last compression
1098 $accessdata['loaded'] = array(); // loaded course contexts
1099 $accessdata['time'] = time();
843ca761 1100 $accessdata['rsw'] = array();
e922fe23 1101
bb2c22bd 1102 return $accessdata;
6f1bce30 1103}
1104
a2cf7f1b 1105/**
e922fe23 1106 * Get accessdata for a given user.
204a369c 1107 *
f76249cc 1108 * @access private
46808d7c 1109 * @param int $userid
e922fe23
PS
1110 * @param bool $preloadonly true means do not return access array
1111 * @return array accessdata
5a4e7398 1112 */
e922fe23
PS
1113function get_user_accessdata($userid, $preloadonly=false) {
1114 global $CFG, $ACCESSLIB_PRIVATE, $USER;
204a369c 1115
529b85b0 1116 if (!empty($USER->access['rdef']) and empty($ACCESSLIB_PRIVATE->rolepermissions)) {
e922fe23 1117 // share rdef from USER session with rolepermissions cache in order to conserve memory
529b85b0
SC
1118 foreach ($USER->access['rdef'] as $k=>$v) {
1119 $ACCESSLIB_PRIVATE->rolepermissions[$k] =& $USER->access['rdef'][$k];
7d0c81b3 1120 }
529b85b0 1121 $ACCESSLIB_PRIVATE->accessdatabyuser[$USER->id] = $USER->access;
204a369c 1122 }
1123
e922fe23
PS
1124 if (!isset($ACCESSLIB_PRIVATE->accessdatabyuser[$userid])) {
1125 if (empty($userid)) {
1126 if (!empty($CFG->notloggedinroleid)) {
1127 $accessdata = get_role_access($CFG->notloggedinroleid);
1128 } else {
1129 // weird
1130 return get_empty_accessdata();
1131 }
1132
1133 } else if (isguestuser($userid)) {
1134 if ($guestrole = get_guest_role()) {
1135 $accessdata = get_role_access($guestrole->id);
1136 } else {
1137 //weird
1138 return get_empty_accessdata();
1139 }
1140
1141 } else {
1142 $accessdata = get_user_access_sitewide($userid); // includes default role and frontpage role
4e1fe7d1 1143 }
128f0984 1144
e922fe23
PS
1145 $ACCESSLIB_PRIVATE->accessdatabyuser[$userid] = $accessdata;
1146 }
a2cf7f1b 1147
e922fe23
PS
1148 if ($preloadonly) {
1149 return;
1150 } else {
1151 return $ACCESSLIB_PRIVATE->accessdatabyuser[$userid];
1152 }
204a369c 1153}
ef989bd9 1154
a2cf7f1b 1155/**
e922fe23
PS
1156 * Try to minimise the size of $USER->access by eliminating duplicate override storage,
1157 * this function looks for contexts with the same overrides and shares them.
cc3edaa4 1158 *
f76249cc 1159 * @access private
e922fe23 1160 * @return void
a2cf7f1b 1161 */
e922fe23
PS
1162function dedupe_user_access() {
1163 global $USER;
a2cf7f1b 1164
e922fe23
PS
1165 if (CLI_SCRIPT) {
1166 // no session in CLI --> no compression necessary
1167 return;
1168 }
a2cf7f1b 1169
e922fe23
PS
1170 if (empty($USER->access['rdef_count'])) {
1171 // weird, this should not happen
1172 return;
1173 }
1174
1175 // the rdef is growing only, we never remove stuff from it, the rdef_lcc helps us to detect new stuff in rdef
1176 if ($USER->access['rdef_count'] - $USER->access['rdef_lcc'] > 10) {
1177 // do not compress after each change, wait till there is more stuff to be done
1178 return;
1179 }
1180
1181 $hashmap = array();
1182 foreach ($USER->access['rdef'] as $k=>$def) {
1183 $hash = sha1(serialize($def));
1184 if (isset($hashmap[$hash])) {
1185 $USER->access['rdef'][$k] =& $hashmap[$hash];
1186 } else {
1187 $hashmap[$hash] =& $USER->access['rdef'][$k];
a2cf7f1b 1188 }
a2cf7f1b 1189 }
e922fe23
PS
1190
1191 $USER->access['rdef_lcc'] = $USER->access['rdef_count'];
a2cf7f1b 1192}
1193
6f1bce30 1194/**
46808d7c 1195 * A convenience function to completely load all the capabilities
e922fe23
PS
1196 * for the current user. It is called from has_capability() and functions change permissions.
1197 *
1198 * Call it only _after_ you've setup $USER and called check_enrolment_plugins();
46808d7c 1199 * @see check_enrolment_plugins()
117bd748 1200 *
f76249cc 1201 * @access private
62e65b21 1202 * @return void
2f1a4248 1203 */
1204function load_all_capabilities() {
e922fe23 1205 global $USER;
bbbf2d40 1206
18818abf 1207 // roles not installed yet - we are in the middle of installation
31a99877 1208 if (during_initial_install()) {
1045a007 1209 return;
1210 }
1211
e922fe23
PS
1212 if (!isset($USER->id)) {
1213 // this should not happen
1214 $USER->id = 0;
2f1a4248 1215 }
55e68c29 1216
e922fe23
PS
1217 unset($USER->access);
1218 $USER->access = get_user_accessdata($USER->id);
1219
1220 // deduplicate the overrides to minimize session size
1221 dedupe_user_access();
55e68c29 1222
1223 // Clear to force a refresh
e922fe23 1224 unset($USER->mycourses);
bbfdff34
PS
1225
1226 // init/reset internal enrol caches - active course enrolments and temp access
1227 $USER->enrol = array('enrolled'=>array(), 'tempguest'=>array());
bbbf2d40 1228}
1229
ef989bd9 1230/**
5a4e7398 1231 * A convenience function to completely reload all the capabilities
ef989bd9 1232 * for the current user when roles have been updated in a relevant
5a4e7398 1233 * context -- but PRESERVING switchroles and loginas.
e922fe23 1234 * This function resets all accesslib and context caches.
ef989bd9 1235 *
1236 * That is - completely transparent to the user.
5a4e7398 1237 *
e922fe23 1238 * Note: reloads $USER->access completely.
ef989bd9 1239 *
f76249cc 1240 * @access private
62e65b21 1241 * @return void
ef989bd9 1242 */
1243function reload_all_capabilities() {
e922fe23 1244 global $USER, $DB, $ACCESSLIB_PRIVATE;
ef989bd9 1245
ef989bd9 1246 // copy switchroles
1247 $sw = array();
843ca761 1248 if (!empty($USER->access['rsw'])) {
ef989bd9 1249 $sw = $USER->access['rsw'];
ef989bd9 1250 }
1251
e922fe23 1252 accesslib_clear_all_caches(true);
ef989bd9 1253 unset($USER->access);
e922fe23 1254 $ACCESSLIB_PRIVATE->dirtycontexts = array(); // prevent dirty flags refetching on this page
5a4e7398 1255
ef989bd9 1256 load_all_capabilities();
1257
1258 foreach ($sw as $path => $roleid) {
e922fe23
PS
1259 if ($record = $DB->get_record('context', array('path'=>$path))) {
1260 $context = context::instance_by_id($record->id);
1261 role_switch($roleid, $context);
1262 }
ef989bd9 1263 }
ef989bd9 1264}
2f1a4248 1265
f33e1ed4 1266/**
e922fe23 1267 * Adds a temp role to current USER->access array.
343effbe 1268 *
e922fe23 1269 * Useful for the "temporary guest" access we grant to logged-in users.
f76249cc 1270 * This is useful for enrol plugins only.
343effbe 1271 *
5bcfd504 1272 * @since Moodle 2.2
e922fe23 1273 * @param context_course $coursecontext
46808d7c 1274 * @param int $roleid
e922fe23 1275 * @return void
343effbe 1276 */
e922fe23 1277function load_temp_course_role(context_course $coursecontext, $roleid) {
bbfdff34 1278 global $USER, $SITE;
5a4e7398 1279
e922fe23
PS
1280 if (empty($roleid)) {
1281 debugging('invalid role specified in load_temp_course_role()');
1282 return;
1283 }
343effbe 1284
bbfdff34
PS
1285 if ($coursecontext->instanceid == $SITE->id) {
1286 debugging('Can not use temp roles on the frontpage');
1287 return;
1288 }
1289
e922fe23
PS
1290 if (!isset($USER->access)) {
1291 load_all_capabilities();
f33e1ed4 1292 }
343effbe 1293
e922fe23 1294 $coursecontext->reload_if_dirty();
343effbe 1295
e922fe23
PS
1296 if (isset($USER->access['ra'][$coursecontext->path][$roleid])) {
1297 return;
343effbe 1298 }
1299
e922fe23
PS
1300 // load course stuff first
1301 load_course_context($USER->id, $coursecontext, $USER->access);
1302
1303 $USER->access['ra'][$coursecontext->path][(int)$roleid] = (int)$roleid;
1304
1305 load_role_access_by_context($roleid, $coursecontext, $USER->access);
343effbe 1306}
1307
efe12f6c 1308/**
e922fe23 1309 * Removes any extra guest roles from current USER->access array.
f76249cc 1310 * This is useful for enrol plugins only.
e922fe23 1311 *
5bcfd504 1312 * @since Moodle 2.2
e922fe23
PS
1313 * @param context_course $coursecontext
1314 * @return void
64026e8c 1315 */
e922fe23 1316function remove_temp_course_roles(context_course $coursecontext) {
bbfdff34
PS
1317 global $DB, $USER, $SITE;
1318
1319 if ($coursecontext->instanceid == $SITE->id) {
1320 debugging('Can not use temp roles on the frontpage');
1321 return;
1322 }
e922fe23
PS
1323
1324 if (empty($USER->access['ra'][$coursecontext->path])) {
1325 //no roles here, weird
1326 return;
1327 }
1328
df997f84
PS
1329 $sql = "SELECT DISTINCT ra.roleid AS id
1330 FROM {role_assignments} ra
1331 WHERE ra.contextid = :contextid AND ra.userid = :userid";
e922fe23 1332 $ras = $DB->get_records_sql($sql, array('contextid'=>$coursecontext->id, 'userid'=>$USER->id));
e4ec4e41 1333
e922fe23
PS
1334 $USER->access['ra'][$coursecontext->path] = array();
1335 foreach($ras as $r) {
1336 $USER->access['ra'][$coursecontext->path][(int)$r->id] = (int)$r->id;
0831484c 1337 }
64026e8c 1338}
1339
3562486b 1340/**
4f0c2d00 1341 * Returns array of all role archetypes.
cc3edaa4 1342 *
46808d7c 1343 * @return array
3562486b 1344 */
4f0c2d00 1345function get_role_archetypes() {
3562486b 1346 return array(
4f0c2d00
PS
1347 'manager' => 'manager',
1348 'coursecreator' => 'coursecreator',
1349 'editingteacher' => 'editingteacher',
1350 'teacher' => 'teacher',
1351 'student' => 'student',
1352 'guest' => 'guest',
1353 'user' => 'user',
1354 'frontpage' => 'frontpage'
3562486b 1355 );
1356}
1357
bbbf2d40 1358/**
4f65e0fb 1359 * Assign the defaults found in this capability definition to roles that have
bbbf2d40 1360 * the corresponding legacy capabilities assigned to them.
cc3edaa4 1361 *
46808d7c 1362 * @param string $capability
1363 * @param array $legacyperms an array in the format (example):
bbbf2d40 1364 * 'guest' => CAP_PREVENT,
1365 * 'student' => CAP_ALLOW,
1366 * 'teacher' => CAP_ALLOW,
1367 * 'editingteacher' => CAP_ALLOW,
1368 * 'coursecreator' => CAP_ALLOW,
4f0c2d00 1369 * 'manager' => CAP_ALLOW
46808d7c 1370 * @return boolean success or failure.
bbbf2d40 1371 */
1372function assign_legacy_capabilities($capability, $legacyperms) {
eef868d1 1373
4f0c2d00 1374 $archetypes = get_role_archetypes();
3562486b 1375
bbbf2d40 1376 foreach ($legacyperms as $type => $perm) {
eef868d1 1377
e922fe23 1378 $systemcontext = context_system::instance();
4f0c2d00
PS
1379 if ($type === 'admin') {
1380 debugging('Legacy type admin in access.php was renamed to manager, please update the code.');
1381 $type = 'manager';
1382 }
eef868d1 1383
4f0c2d00 1384 if (!array_key_exists($type, $archetypes)) {
e49ef64a 1385 print_error('invalidlegacy', '', '', $type);
3562486b 1386 }
eef868d1 1387
4f0c2d00 1388 if ($roles = get_archetype_roles($type)) {
2e85fffe 1389 foreach ($roles as $role) {
1390 // Assign a site level capability.
1391 if (!assign_capability($capability, $perm, $role->id, $systemcontext->id)) {
1392 return false;
1393 }
bbbf2d40 1394 }
1395 }
1396 }
1397 return true;
1398}
1399
faf75fe7 1400/**
e922fe23
PS
1401 * Verify capability risks.
1402 *
f76249cc 1403 * @param stdClass $capability a capability - a row from the capabilities table.
ed149942 1404 * @return boolean whether this capability is safe - that is, whether people with the
faf75fe7 1405 * safeoverrides capability should be allowed to change it.
1406 */
1407function is_safe_capability($capability) {
4659454a 1408 return !((RISK_DATALOSS | RISK_MANAGETRUST | RISK_CONFIG | RISK_XSS | RISK_PERSONAL) & $capability->riskbitmask);
faf75fe7 1409}
cee0901c 1410
bbbf2d40 1411/**
e922fe23 1412 * Get the local override (if any) for a given capability in a role in a context
a0760047 1413 *
e922fe23
PS
1414 * @param int $roleid
1415 * @param int $contextid
1416 * @param string $capability
1417 * @return stdClass local capability override
bbbf2d40 1418 */
e922fe23
PS
1419function get_local_override($roleid, $contextid, $capability) {
1420 global $DB;
1421 return $DB->get_record('role_capabilities', array('roleid'=>$roleid, 'capability'=>$capability, 'contextid'=>$contextid));
1422}
e40413be 1423
e922fe23
PS
1424/**
1425 * Returns context instance plus related course and cm instances
1426 *
1427 * @param int $contextid
1428 * @return array of ($context, $course, $cm)
1429 */
1430function get_context_info_array($contextid) {
74df2951
DW
1431 global $DB;
1432
e922fe23
PS
1433 $context = context::instance_by_id($contextid, MUST_EXIST);
1434 $course = null;
1435 $cm = null;
e40413be 1436
e922fe23 1437 if ($context->contextlevel == CONTEXT_COURSE) {
74df2951 1438 $course = $DB->get_record('course', array('id'=>$context->instanceid), '*', MUST_EXIST);
e40413be 1439
e922fe23
PS
1440 } else if ($context->contextlevel == CONTEXT_MODULE) {
1441 $cm = get_coursemodule_from_id('', $context->instanceid, 0, false, MUST_EXIST);
74df2951 1442 $course = $DB->get_record('course', array('id'=>$cm->course), '*', MUST_EXIST);
7d0c81b3 1443
e922fe23
PS
1444 } else if ($context->contextlevel == CONTEXT_BLOCK) {
1445 $parent = $context->get_parent_context();
f689028c 1446
e922fe23 1447 if ($parent->contextlevel == CONTEXT_COURSE) {
74df2951 1448 $course = $DB->get_record('course', array('id'=>$parent->instanceid), '*', MUST_EXIST);
e922fe23
PS
1449 } else if ($parent->contextlevel == CONTEXT_MODULE) {
1450 $cm = get_coursemodule_from_id('', $parent->instanceid, 0, false, MUST_EXIST);
74df2951 1451 $course = $DB->get_record('course', array('id'=>$cm->course), '*', MUST_EXIST);
e922fe23 1452 }
bbbf2d40 1453 }
4f0c2d00 1454
e922fe23 1455 return array($context, $course, $cm);
bbbf2d40 1456}
1457
efe12f6c 1458/**
e922fe23 1459 * Function that creates a role
46808d7c 1460 *
e922fe23
PS
1461 * @param string $name role name
1462 * @param string $shortname role short name
1463 * @param string $description role description
1464 * @param string $archetype
1465 * @return int id or dml_exception
8ba412da 1466 */
e922fe23
PS
1467function create_role($name, $shortname, $description, $archetype = '') {
1468 global $DB;
7d0c81b3 1469
e922fe23
PS
1470 if (strpos($archetype, 'moodle/legacy:') !== false) {
1471 throw new coding_exception('Use new role archetype parameter in create_role() instead of old legacy capabilities.');
8ba412da 1472 }
7d0c81b3 1473
e922fe23
PS
1474 // verify role archetype actually exists
1475 $archetypes = get_role_archetypes();
1476 if (empty($archetypes[$archetype])) {
1477 $archetype = '';
7d0c81b3 1478 }
1479
e922fe23
PS
1480 // Insert the role record.
1481 $role = new stdClass();
1482 $role->name = $name;
1483 $role->shortname = $shortname;
1484 $role->description = $description;
1485 $role->archetype = $archetype;
1486
1487 //find free sortorder number
1488 $role->sortorder = $DB->get_field('role', 'MAX(sortorder) + 1', array());
1489 if (empty($role->sortorder)) {
1490 $role->sortorder = 1;
7d0c81b3 1491 }
e922fe23 1492 $id = $DB->insert_record('role', $role);
7d0c81b3 1493
e922fe23 1494 return $id;
8ba412da 1495}
b51ece5b 1496
9991d157 1497/**
e922fe23 1498 * Function that deletes a role and cleanups up after it
cc3edaa4 1499 *
e922fe23
PS
1500 * @param int $roleid id of role to delete
1501 * @return bool always true
9991d157 1502 */
e922fe23
PS
1503function delete_role($roleid) {
1504 global $DB;
b51ece5b 1505
e922fe23
PS
1506 // first unssign all users
1507 role_unassign_all(array('roleid'=>$roleid));
2ac56258 1508
e922fe23
PS
1509 // cleanup all references to this role, ignore errors
1510 $DB->delete_records('role_capabilities', array('roleid'=>$roleid));
1511 $DB->delete_records('role_allow_assign', array('roleid'=>$roleid));
1512 $DB->delete_records('role_allow_assign', array('allowassign'=>$roleid));
1513 $DB->delete_records('role_allow_override', array('roleid'=>$roleid));
1514 $DB->delete_records('role_allow_override', array('allowoverride'=>$roleid));
1515 $DB->delete_records('role_names', array('roleid'=>$roleid));
1516 $DB->delete_records('role_context_levels', array('roleid'=>$roleid));
a05bcfba 1517
a7524e35
RT
1518 // Get role record before it's deleted.
1519 $role = $DB->get_record('role', array('id'=>$roleid));
582bae08 1520
a7524e35 1521 // Finally delete the role itself.
e922fe23 1522 $DB->delete_records('role', array('id'=>$roleid));
582bae08 1523
a7524e35
RT
1524 // Trigger event.
1525 $event = \core\event\role_deleted::create(
1526 array(
1527 'context' => context_system::instance(),
1528 'objectid' => $roleid,
1529 'other' =>
1530 array(
a7524e35
RT
1531 'shortname' => $role->shortname,
1532 'description' => $role->description,
1533 'archetype' => $role->archetype
1534 )
1535 )
1536 );
1537 $event->add_record_snapshot('role', $role);
1538 $event->trigger();
196f1a25
PS
1539
1540 return true;
9991d157 1541}
1542
9a81a606 1543/**
e922fe23 1544 * Function to write context specific overrides, or default capabilities.
cc3edaa4 1545 *
e922fe23
PS
1546 * NOTE: use $context->mark_dirty() after this
1547 *
1548 * @param string $capability string name
1549 * @param int $permission CAP_ constants
1550 * @param int $roleid role id
1551 * @param int|context $contextid context id
1552 * @param bool $overwrite
1553 * @return bool always true or exception
9a81a606 1554 */
e922fe23
PS
1555function assign_capability($capability, $permission, $roleid, $contextid, $overwrite = false) {
1556 global $USER, $DB;
9a81a606 1557
e922fe23
PS
1558 if ($contextid instanceof context) {
1559 $context = $contextid;
1560 } else {
1561 $context = context::instance_by_id($contextid);
9a81a606 1562 }
1563
e922fe23
PS
1564 if (empty($permission) || $permission == CAP_INHERIT) { // if permission is not set
1565 unassign_capability($capability, $roleid, $context->id);
1566 return true;
9a81a606 1567 }
1568
e922fe23 1569 $existing = $DB->get_record('role_capabilities', array('contextid'=>$context->id, 'roleid'=>$roleid, 'capability'=>$capability));
9a81a606 1570
e922fe23
PS
1571 if ($existing and !$overwrite) { // We want to keep whatever is there already
1572 return true;
9a81a606 1573 }
1574
e922fe23
PS
1575 $cap = new stdClass();
1576 $cap->contextid = $context->id;
1577 $cap->roleid = $roleid;
1578 $cap->capability = $capability;
1579 $cap->permission = $permission;
1580 $cap->timemodified = time();
1581 $cap->modifierid = empty($USER->id) ? 0 : $USER->id;
e92c286c 1582
e922fe23
PS
1583 if ($existing) {
1584 $cap->id = $existing->id;
1585 $DB->update_record('role_capabilities', $cap);
1586 } else {
1587 if ($DB->record_exists('context', array('id'=>$context->id))) {
1588 $DB->insert_record('role_capabilities', $cap);
1589 }
9a81a606 1590 }
e922fe23 1591 return true;
9a81a606 1592}
1593
17b0efae 1594/**
e922fe23 1595 * Unassign a capability from a role.
17b0efae 1596 *
e922fe23
PS
1597 * NOTE: use $context->mark_dirty() after this
1598 *
1599 * @param string $capability the name of the capability
1600 * @param int $roleid the role id
1601 * @param int|context $contextid null means all contexts
1602 * @return boolean true or exception
17b0efae 1603 */
e922fe23 1604function unassign_capability($capability, $roleid, $contextid = null) {
5a4e7398 1605 global $DB;
17b0efae 1606
e922fe23
PS
1607 if (!empty($contextid)) {
1608 if ($contextid instanceof context) {
1609 $context = $contextid;
1610 } else {
1611 $context = context::instance_by_id($contextid);
1612 }
1613 // delete from context rel, if this is the last override in this context
1614 $DB->delete_records('role_capabilities', array('capability'=>$capability, 'roleid'=>$roleid, 'contextid'=>$context->id));
1615 } else {
1616 $DB->delete_records('role_capabilities', array('capability'=>$capability, 'roleid'=>$roleid));
17b0efae 1617 }
1618 return true;
1619}
1620
00653161 1621/**
e922fe23 1622 * Get the roles that have a given capability assigned to it
00653161 1623 *
e922fe23
PS
1624 * This function does not resolve the actual permission of the capability.
1625 * It just checks for permissions and overrides.
1626 * Use get_roles_with_cap_in_context() if resolution is required.
1627 *
34223e03
SH
1628 * @param string $capability capability name (string)
1629 * @param string $permission optional, the permission defined for this capability
e922fe23 1630 * either CAP_ALLOW, CAP_PREVENT or CAP_PROHIBIT. Defaults to null which means any.
34223e03 1631 * @param stdClass $context null means any
e922fe23 1632 * @return array of role records
00653161 1633 */
e922fe23
PS
1634function get_roles_with_capability($capability, $permission = null, $context = null) {
1635 global $DB;
00653161 1636
e922fe23
PS
1637 if ($context) {
1638 $contexts = $context->get_parent_context_ids(true);
1639 list($insql, $params) = $DB->get_in_or_equal($contexts, SQL_PARAMS_NAMED, 'ctx');
1640 $contextsql = "AND rc.contextid $insql";
1641 } else {
1642 $params = array();
1643 $contextsql = '';
00653161 1644 }
1645
e922fe23
PS
1646 if ($permission) {
1647 $permissionsql = " AND rc.permission = :permission";
1648 $params['permission'] = $permission;
1649 } else {
1650 $permissionsql = '';
00653161 1651 }
e922fe23
PS
1652
1653 $sql = "SELECT r.*
1654 FROM {role} r
1655 WHERE r.id IN (SELECT rc.roleid
1656 FROM {role_capabilities} rc
1657 WHERE rc.capability = :capname
1658 $contextsql
1659 $permissionsql)";
1660 $params['capname'] = $capability;
1661
1662
1663 return $DB->get_records_sql($sql, $params);
00653161 1664}
1665
bbbf2d40 1666/**
e922fe23 1667 * This function makes a role-assignment (a role for a user in a particular context)
46808d7c 1668 *
e922fe23
PS
1669 * @param int $roleid the role of the id
1670 * @param int $userid userid
1671 * @param int|context $contextid id of the context
1672 * @param string $component example 'enrol_ldap', defaults to '' which means manual assignment,
1673 * @param int $itemid id of enrolment/auth plugin
1674 * @param string $timemodified defaults to current time
1675 * @return int new/existing id of the assignment
bbbf2d40 1676 */
e922fe23
PS
1677function role_assign($roleid, $userid, $contextid, $component = '', $itemid = 0, $timemodified = '') {
1678 global $USER, $DB;
d9a35e12 1679
e922fe23
PS
1680 // first of all detect if somebody is using old style parameters
1681 if ($contextid === 0 or is_numeric($component)) {
1682 throw new coding_exception('Invalid call to role_assign(), code needs to be updated to use new order of parameters');
8ba412da 1683 }
1684
e922fe23
PS
1685 // now validate all parameters
1686 if (empty($roleid)) {
1687 throw new coding_exception('Invalid call to role_assign(), roleid can not be empty');
a36a3a3f 1688 }
1689
e922fe23
PS
1690 if (empty($userid)) {
1691 throw new coding_exception('Invalid call to role_assign(), userid can not be empty');
1692 }
d0e538ba 1693
e922fe23
PS
1694 if ($itemid) {
1695 if (strpos($component, '_') === false) {
1696 throw new coding_exception('Invalid call to role_assign(), component must start with plugin type such as"enrol_" when itemid specified', 'component:'.$component);
65bcf17b 1697 }
e922fe23
PS
1698 } else {
1699 $itemid = 0;
1700 if ($component !== '' and strpos($component, '_') === false) {
1701 throw new coding_exception('Invalid call to role_assign(), invalid component string', 'component:'.$component);
65bcf17b 1702 }
e922fe23 1703 }
65bcf17b 1704
e922fe23
PS
1705 if (!$DB->record_exists('user', array('id'=>$userid, 'deleted'=>0))) {
1706 throw new coding_exception('User ID does not exist or is deleted!', 'userid:'.$userid);
1707 }
65bcf17b 1708
e922fe23
PS
1709 if ($contextid instanceof context) {
1710 $context = $contextid;
1711 } else {
1712 $context = context::instance_by_id($contextid, MUST_EXIST);
e5605780 1713 }
1714
e922fe23
PS
1715 if (!$timemodified) {
1716 $timemodified = time();
1717 }
65bcf17b 1718
e968c5f9 1719 // Check for existing entry
e922fe23 1720 $ras = $DB->get_records('role_assignments', array('roleid'=>$roleid, 'contextid'=>$context->id, 'userid'=>$userid, 'component'=>$component, 'itemid'=>$itemid), 'id');
65bcf17b 1721
e922fe23
PS
1722 if ($ras) {
1723 // role already assigned - this should not happen
1724 if (count($ras) > 1) {
1725 // very weird - remove all duplicates!
1726 $ra = array_shift($ras);
1727 foreach ($ras as $r) {
1728 $DB->delete_records('role_assignments', array('id'=>$r->id));
1729 }
1730 } else {
1731 $ra = reset($ras);
65bcf17b 1732 }
e5605780 1733
e922fe23
PS
1734 // actually there is no need to update, reset anything or trigger any event, so just return
1735 return $ra->id;
1736 }
5a4e7398 1737
e922fe23
PS
1738 // Create a new entry
1739 $ra = new stdClass();
1740 $ra->roleid = $roleid;
1741 $ra->contextid = $context->id;
1742 $ra->userid = $userid;
1743 $ra->component = $component;
1744 $ra->itemid = $itemid;
1745 $ra->timemodified = $timemodified;
1746 $ra->modifierid = empty($USER->id) ? 0 : $USER->id;
cd5be9a5 1747 $ra->sortorder = 0;
65bcf17b 1748
e922fe23 1749 $ra->id = $DB->insert_record('role_assignments', $ra);
65bcf17b 1750
e922fe23
PS
1751 // mark context as dirty - again expensive, but needed
1752 $context->mark_dirty();
65bcf17b 1753
e922fe23
PS
1754 if (!empty($USER->id) && $USER->id == $userid) {
1755 // If the user is the current user, then do full reload of capabilities too.
1756 reload_all_capabilities();
ccfc5ecc 1757 }
0468976c 1758
02a5a4b2
MN
1759 $event = \core\event\role_assigned::create(array(
1760 'context' => $context,
1761 'objectid' => $ra->roleid,
1762 'relateduserid' => $ra->userid,
1763 'other' => array(
1764 'id' => $ra->id,
1765 'component' => $ra->component,
1766 'itemid' => $ra->itemid
1767 )
1768 ));
5fef139c 1769 $event->add_record_snapshot('role_assignments', $ra);
b474bec3 1770 $event->trigger();
bbbf2d40 1771
e922fe23
PS
1772 return $ra->id;
1773}
cee0901c 1774
340ea4e8 1775/**
e922fe23 1776 * Removes one role assignment
cc3edaa4 1777 *
e922fe23
PS
1778 * @param int $roleid
1779 * @param int $userid
fbf4acdc 1780 * @param int $contextid
e922fe23
PS
1781 * @param string $component
1782 * @param int $itemid
1783 * @return void
340ea4e8 1784 */
e922fe23
PS
1785function role_unassign($roleid, $userid, $contextid, $component = '', $itemid = 0) {
1786 // first make sure the params make sense
1787 if ($roleid == 0 or $userid == 0 or $contextid == 0) {
1788 throw new coding_exception('Invalid call to role_unassign(), please use role_unassign_all() when removing multiple role assignments');
340ea4e8 1789 }
1790
e922fe23
PS
1791 if ($itemid) {
1792 if (strpos($component, '_') === false) {
1793 throw new coding_exception('Invalid call to role_assign(), component must start with plugin type such as "enrol_" when itemid specified', 'component:'.$component);
1794 }
1795 } else {
1796 $itemid = 0;
1797 if ($component !== '' and strpos($component, '_') === false) {
1798 throw new coding_exception('Invalid call to role_assign(), invalid component string', 'component:'.$component);
1799 }
340ea4e8 1800 }
1801
e922fe23 1802 role_unassign_all(array('roleid'=>$roleid, 'userid'=>$userid, 'contextid'=>$contextid, 'component'=>$component, 'itemid'=>$itemid), false, false);
340ea4e8 1803}
1804
8737be58 1805/**
e922fe23
PS
1806 * Removes multiple role assignments, parameters may contain:
1807 * 'roleid', 'userid', 'contextid', 'component', 'enrolid'.
cc3edaa4 1808 *
e922fe23
PS
1809 * @param array $params role assignment parameters
1810 * @param bool $subcontexts unassign in subcontexts too
1811 * @param bool $includemanual include manual role assignments too
1812 * @return void
01a2ce80 1813 */
e922fe23
PS
1814function role_unassign_all(array $params, $subcontexts = false, $includemanual = false) {
1815 global $USER, $CFG, $DB;
01a2ce80 1816
e922fe23
PS
1817 if (!$params) {
1818 throw new coding_exception('Missing parameters in role_unsassign_all() call');
1819 }
01a2ce80 1820
e922fe23
PS
1821 $allowed = array('roleid', 'userid', 'contextid', 'component', 'itemid');
1822 foreach ($params as $key=>$value) {
1823 if (!in_array($key, $allowed)) {
1824 throw new coding_exception('Unknown role_unsassign_all() parameter key', 'key:'.$key);
01a2ce80
PS
1825 }
1826 }
1827
e922fe23
PS
1828 if (isset($params['component']) and $params['component'] !== '' and strpos($params['component'], '_') === false) {
1829 throw new coding_exception('Invalid component paramter in role_unsassign_all() call', 'component:'.$params['component']);
28765cfc 1830 }
e922fe23
PS
1831
1832 if ($includemanual) {
1833 if (!isset($params['component']) or $params['component'] === '') {
1834 throw new coding_exception('include manual parameter requires component parameter in role_unsassign_all() call');
1835 }
35716b86
PS
1836 }
1837
e922fe23
PS
1838 if ($subcontexts) {
1839 if (empty($params['contextid'])) {
1840 throw new coding_exception('subcontexts paramtere requires component parameter in role_unsassign_all() call');
1841 }
35716b86
PS
1842 }
1843
e922fe23
PS
1844 $ras = $DB->get_records('role_assignments', $params);
1845 foreach($ras as $ra) {
1846 $DB->delete_records('role_assignments', array('id'=>$ra->id));
1847 if ($context = context::instance_by_id($ra->contextid, IGNORE_MISSING)) {
1848 // this is a bit expensive but necessary
1849 $context->mark_dirty();
34223e03 1850 // If the user is the current user, then do full reload of capabilities too.
e922fe23
PS
1851 if (!empty($USER->id) && $USER->id == $ra->userid) {
1852 reload_all_capabilities();
1853 }
02a5a4b2
MN
1854 $event = \core\event\role_unassigned::create(array(
1855 'context' => $context,
1856 'objectid' => $ra->roleid,
1857 'relateduserid' => $ra->userid,
1858 'other' => array(
1859 'id' => $ra->id,
1860 'component' => $ra->component,
1861 'itemid' => $ra->itemid
1862 )
1863 ));
5fef139c 1864 $event->add_record_snapshot('role_assignments', $ra);
b474bec3 1865 $event->trigger();
e922fe23 1866 }
35716b86 1867 }
e922fe23
PS
1868 unset($ras);
1869
1870 // process subcontexts
1871 if ($subcontexts and $context = context::instance_by_id($params['contextid'], IGNORE_MISSING)) {
1872 if ($params['contextid'] instanceof context) {
1873 $context = $params['contextid'];
1874 } else {
1875 $context = context::instance_by_id($params['contextid'], IGNORE_MISSING);
1876 }
35716b86 1877
e922fe23
PS
1878 if ($context) {
1879 $contexts = $context->get_child_contexts();
1880 $mparams = $params;
1881 foreach($contexts as $context) {
1882 $mparams['contextid'] = $context->id;
1883 $ras = $DB->get_records('role_assignments', $mparams);
1884 foreach($ras as $ra) {
1885 $DB->delete_records('role_assignments', array('id'=>$ra->id));
1886 // this is a bit expensive but necessary
1887 $context->mark_dirty();
34223e03 1888 // If the user is the current user, then do full reload of capabilities too.
e922fe23
PS
1889 if (!empty($USER->id) && $USER->id == $ra->userid) {
1890 reload_all_capabilities();
1891 }
b474bec3
PS
1892 $event = \core\event\role_unassigned::create(
1893 array('context'=>$context, 'objectid'=>$ra->roleid, 'relateduserid'=>$ra->userid,
c4297815 1894 'other'=>array('id'=>$ra->id, 'component'=>$ra->component, 'itemid'=>$ra->itemid)));
5fef139c 1895 $event->add_record_snapshot('role_assignments', $ra);
b474bec3 1896 $event->trigger();
e922fe23
PS
1897 }
1898 }
1899 }
35716b86
PS
1900 }
1901
e922fe23
PS
1902 // do this once more for all manual role assignments
1903 if ($includemanual) {
1904 $params['component'] = '';
1905 role_unassign_all($params, $subcontexts, false);
1906 }
35716b86
PS
1907}
1908
e922fe23
PS
1909/**
1910 * Determines if a user is currently logged in
1911 *
f76249cc
PS
1912 * @category access
1913 *
e922fe23
PS
1914 * @return bool
1915 */
1916function isloggedin() {
1917 global $USER;
bbbf2d40 1918
e922fe23
PS
1919 return (!empty($USER->id));
1920}
bbbf2d40 1921
cee0901c 1922/**
e922fe23 1923 * Determines if a user is logged in as real guest user with username 'guest'.
cc3edaa4 1924 *
f76249cc
PS
1925 * @category access
1926 *
e922fe23
PS
1927 * @param int|object $user mixed user object or id, $USER if not specified
1928 * @return bool true if user is the real guest user, false if not logged in or other user
bbbf2d40 1929 */
e922fe23
PS
1930function isguestuser($user = null) {
1931 global $USER, $DB, $CFG;
eef868d1 1932
e922fe23
PS
1933 // make sure we have the user id cached in config table, because we are going to use it a lot
1934 if (empty($CFG->siteguest)) {
1935 if (!$guestid = $DB->get_field('user', 'id', array('username'=>'guest', 'mnethostid'=>$CFG->mnet_localhost_id))) {
1936 // guest does not exist yet, weird
1937 return false;
1938 }
1939 set_config('siteguest', $guestid);
4f0c2d00 1940 }
e922fe23
PS
1941 if ($user === null) {
1942 $user = $USER;
4f0c2d00
PS
1943 }
1944
e922fe23
PS
1945 if ($user === null) {
1946 // happens when setting the $USER
1947 return false;
31f26796 1948
e922fe23
PS
1949 } else if (is_numeric($user)) {
1950 return ($CFG->siteguest == $user);
eef868d1 1951
e922fe23
PS
1952 } else if (is_object($user)) {
1953 if (empty($user->id)) {
1954 return false; // not logged in means is not be guest
1955 } else {
1956 return ($CFG->siteguest == $user->id);
1957 }
b5959f30 1958
e922fe23
PS
1959 } else {
1960 throw new coding_exception('Invalid user parameter supplied for isguestuser() function!');
1961 }
bbbf2d40 1962}
1963
8420bee9 1964/**
e922fe23 1965 * Does user have a (temporary or real) guest access to course?
cc3edaa4 1966 *
f76249cc
PS
1967 * @category access
1968 *
e922fe23
PS
1969 * @param context $context
1970 * @param stdClass|int $user
1971 * @return bool
8420bee9 1972 */
e922fe23
PS
1973function is_guest(context $context, $user = null) {
1974 global $USER;
c421ad4b 1975
e922fe23
PS
1976 // first find the course context
1977 $coursecontext = $context->get_course_context();
c421ad4b 1978
e922fe23
PS
1979 // make sure there is a real user specified
1980 if ($user === null) {
1981 $userid = isset($USER->id) ? $USER->id : 0;
1982 } else {
1983 $userid = is_object($user) ? $user->id : $user;
1984 }
60ace1e1 1985
e922fe23
PS
1986 if (isguestuser($userid)) {
1987 // can not inspect or be enrolled
1988 return true;
1989 }
5a4e7398 1990
e922fe23
PS
1991 if (has_capability('moodle/course:view', $coursecontext, $user)) {
1992 // viewing users appear out of nowhere, they are neither guests nor participants
1993 return false;
1994 }
5a4e7398 1995
e922fe23
PS
1996 // consider only real active enrolments here
1997 if (is_enrolled($coursecontext, $user, '', true)) {
1998 return false;
1999 }
8420bee9 2000
4f0c2d00 2001 return true;
8420bee9 2002}
2003
bbbf2d40 2004/**
e922fe23
PS
2005 * Returns true if the user has moodle/course:view capability in the course,
2006 * this is intended for admins, managers (aka small admins), inspectors, etc.
46808d7c 2007 *
f76249cc
PS
2008 * @category access
2009 *
e922fe23 2010 * @param context $context
34223e03 2011 * @param int|stdClass $user if null $USER is used
e922fe23
PS
2012 * @param string $withcapability extra capability name
2013 * @return bool
bbbf2d40 2014 */
e922fe23
PS
2015function is_viewing(context $context, $user = null, $withcapability = '') {
2016 // first find the course context
2017 $coursecontext = $context->get_course_context();
eef868d1 2018
e922fe23
PS
2019 if (isguestuser($user)) {
2020 // can not inspect
2021 return false;
98882637 2022 }
eef868d1 2023
e922fe23
PS
2024 if (!has_capability('moodle/course:view', $coursecontext, $user)) {
2025 // admins are allowed to inspect courses
2026 return false;
e7876c1e 2027 }
2028
e922fe23
PS
2029 if ($withcapability and !has_capability($withcapability, $context, $user)) {
2030 // site admins always have the capability, but the enrolment above blocks
2031 return false;
e7876c1e 2032 }
e922fe23 2033
4f0c2d00 2034 return true;
bbbf2d40 2035}
2036
bbbf2d40 2037/**
e922fe23
PS
2038 * Returns true if user is enrolled (is participating) in course
2039 * this is intended for students and teachers.
117bd748 2040 *
bbfdff34
PS
2041 * Since 2.2 the result for active enrolments and current user are cached.
2042 *
f76249cc
PS
2043 * @package core_enrol
2044 * @category access
2045 *
e922fe23 2046 * @param context $context
34223e03 2047 * @param int|stdClass $user if null $USER is used, otherwise user object or id expected
e922fe23
PS
2048 * @param string $withcapability extra capability name
2049 * @param bool $onlyactive consider only active enrolments in enabled plugins and time restrictions
2050 * @return bool
bbbf2d40 2051 */
e922fe23
PS
2052function is_enrolled(context $context, $user = null, $withcapability = '', $onlyactive = false) {
2053 global $USER, $DB;
eef868d1 2054
e922fe23
PS
2055 // first find the course context
2056 $coursecontext = $context->get_course_context();
2057
2058 // make sure there is a real user specified
2059 if ($user === null) {
2060 $userid = isset($USER->id) ? $USER->id : 0;
98882637 2061 } else {
e922fe23 2062 $userid = is_object($user) ? $user->id : $user;
98882637 2063 }
5a4e7398 2064
e922fe23
PS
2065 if (empty($userid)) {
2066 // not-logged-in!
2067 return false;
2068 } else if (isguestuser($userid)) {
2069 // guest account can not be enrolled anywhere
2070 return false;
448aad7f
PS
2071 }
2072
e922fe23
PS
2073 if ($coursecontext->instanceid == SITEID) {
2074 // everybody participates on frontpage
ec7a8b79 2075 } else {
bbfdff34
PS
2076 // try cached info first - the enrolled flag is set only when active enrolment present
2077 if ($USER->id == $userid) {
2078 $coursecontext->reload_if_dirty();
2079 if (isset($USER->enrol['enrolled'][$coursecontext->instanceid])) {
2080 if ($USER->enrol['enrolled'][$coursecontext->instanceid] > time()) {
a386e6e0
ARN
2081 if ($withcapability and !has_capability($withcapability, $context, $userid)) {
2082 return false;
2083 }
bbfdff34 2084 return true;
e922fe23 2085 }
e922fe23 2086 }
bbfdff34
PS
2087 }
2088
2089 if ($onlyactive) {
2090 // look for active enrolments only
2091 $until = enrol_get_enrolment_end($coursecontext->instanceid, $userid);
2092
2093 if ($until === false) {
e922fe23
PS
2094 return false;
2095 }
eef868d1 2096
bbfdff34
PS
2097 if ($USER->id == $userid) {
2098 if ($until == 0) {
2099 $until = ENROL_MAX_TIMESTAMP;
2100 }
2101 $USER->enrol['enrolled'][$coursecontext->instanceid] = $until;
2102 if (isset($USER->enrol['tempguest'][$coursecontext->instanceid])) {
2103 unset($USER->enrol['tempguest'][$coursecontext->instanceid]);
2104 remove_temp_course_roles($coursecontext);
2105 }
2106 }
2107
e922fe23
PS
2108 } else {
2109 // any enrolment is good for us here, even outdated, disabled or inactive
2110 $sql = "SELECT 'x'
2111 FROM {user_enrolments} ue
2112 JOIN {enrol} e ON (e.id = ue.enrolid AND e.courseid = :courseid)
2113 JOIN {user} u ON u.id = ue.userid
2114 WHERE ue.userid = :userid AND u.deleted = 0";
2115 $params = array('userid'=>$userid, 'courseid'=>$coursecontext->instanceid);
2116 if (!$DB->record_exists_sql($sql, $params)) {
2117 return false;
2118 }
2119 }
2120 }
bbbf2d40 2121
e922fe23
PS
2122 if ($withcapability and !has_capability($withcapability, $context, $userid)) {
2123 return false;
2124 }
f33e1ed4 2125
e922fe23 2126 return true;
bbbf2d40 2127}
2128
bbbf2d40 2129/**
e922fe23 2130 * Returns true if the user is able to access the course.
117bd748 2131 *
e922fe23
PS
2132 * This function is in no way, shape, or form a substitute for require_login.
2133 * It should only be used in circumstances where it is not possible to call require_login
2134 * such as the navigation.
2135 *
2136 * This function checks many of the methods of access to a course such as the view
2137 * capability, enrollments, and guest access. It also makes use of the cache
2138 * generated by require_login for guest access.
2139 *
2140 * The flags within the $USER object that are used here should NEVER be used outside
2141 * of this function can_access_course and require_login. Doing so WILL break future
2142 * versions.
2143 *
1344b0ca
PS
2144 * @param stdClass $course record
2145 * @param stdClass|int|null $user user record or id, current user if null
e922fe23
PS
2146 * @param string $withcapability Check for this capability as well.
2147 * @param bool $onlyactive consider only active enrolments in enabled plugins and time restrictions
e922fe23
PS
2148 * @return boolean Returns true if the user is able to access the course
2149 */
1344b0ca 2150function can_access_course(stdClass $course, $user = null, $withcapability = '', $onlyactive = false) {
e922fe23 2151 global $DB, $USER;
eef868d1 2152
1344b0ca
PS
2153 // this function originally accepted $coursecontext parameter
2154 if ($course instanceof context) {
2155 if ($course instanceof context_course) {
2156 debugging('deprecated context parameter, please use $course record');
2157 $coursecontext = $course;
2158 $course = $DB->get_record('course', array('id'=>$coursecontext->instanceid));
2159 } else {
2160 debugging('Invalid context parameter, please use $course record');
2161 return false;
2162 }
2163 } else {
2164 $coursecontext = context_course::instance($course->id);
2165 }
2166
2167 if (!isset($USER->id)) {
2168 // should never happen
2169 $USER->id = 0;
c90e6b46 2170 debugging('Course access check being performed on a user with no ID.', DEBUG_DEVELOPER);
1344b0ca
PS
2171 }
2172
2173 // make sure there is a user specified
2174 if ($user === null) {
2175 $userid = $USER->id;
2176 } else {
2177 $userid = is_object($user) ? $user->id : $user;
2178 }
2179 unset($user);
bbbf2d40 2180
1344b0ca
PS
2181 if ($withcapability and !has_capability($withcapability, $coursecontext, $userid)) {
2182 return false;
2183 }
2184
2185 if ($userid == $USER->id) {
2186 if (!empty($USER->access['rsw'][$coursecontext->path])) {
2187 // the fact that somebody switched role means they can access the course no matter to what role they switched
2188 return true;
2189 }
2190 }
2191
0f14c827 2192 if (!$course->visible and !has_capability('moodle/course:viewhiddencourses', $coursecontext, $userid)) {
1344b0ca
PS
2193 return false;
2194 }
2195
2196 if (is_viewing($coursecontext, $userid)) {
e922fe23 2197 return true;
bbbf2d40 2198 }
2199
1344b0ca
PS
2200 if ($userid != $USER->id) {
2201 // for performance reasons we do not verify temporary guest access for other users, sorry...
2202 return is_enrolled($coursecontext, $userid, '', $onlyactive);
2203 }
2204
0f14c827
PS
2205 // === from here we deal only with $USER ===
2206
bbfdff34
PS
2207 $coursecontext->reload_if_dirty();
2208
1344b0ca 2209 if (isset($USER->enrol['enrolled'][$course->id])) {
bbfdff34 2210 if ($USER->enrol['enrolled'][$course->id] > time()) {
1344b0ca
PS
2211 return true;
2212 }
2213 }
2214 if (isset($USER->enrol['tempguest'][$course->id])) {
bbfdff34 2215 if ($USER->enrol['tempguest'][$course->id] > time()) {
1344b0ca
PS
2216 return true;
2217 }
2218 }
7700027f 2219
bbfdff34 2220 if (is_enrolled($coursecontext, $USER, '', $onlyactive)) {
1344b0ca 2221 return true;
96608a55 2222 }
c421ad4b 2223
1344b0ca
PS
2224 // if not enrolled try to gain temporary guest access
2225 $instances = $DB->get_records('enrol', array('courseid'=>$course->id, 'status'=>ENROL_INSTANCE_ENABLED), 'sortorder, id ASC');
2226 $enrols = enrol_get_plugins(true);
2227 foreach($instances as $instance) {
2228 if (!isset($enrols[$instance->enrol])) {
2229 continue;
2230 }
bbfdff34 2231 // Get a duration for the guest access, a timestamp in the future, 0 (always) or false.
1344b0ca 2232 $until = $enrols[$instance->enrol]->try_guestaccess($instance);
bbfdff34 2233 if ($until !== false and $until > time()) {
1344b0ca
PS
2234 $USER->enrol['tempguest'][$course->id] = $until;
2235 return true;
e922fe23 2236 }
4e5f3064 2237 }
bbfdff34
PS
2238 if (isset($USER->enrol['tempguest'][$course->id])) {
2239 unset($USER->enrol['tempguest'][$course->id]);
2240 remove_temp_course_roles($coursecontext);
2241 }
1344b0ca
PS
2242
2243 return false;
bbbf2d40 2244}
2245
bbbf2d40 2246/**
e922fe23
PS
2247 * Returns array with sql code and parameters returning all ids
2248 * of users enrolled into course.
cc3edaa4 2249 *
e922fe23
PS
2250 * This function is using 'eu[0-9]+_' prefix for table names and parameters.
2251 *
f76249cc
PS
2252 * @package core_enrol
2253 * @category access
2254 *
e922fe23
PS
2255 * @param context $context
2256 * @param string $withcapability
2257 * @param int $groupid 0 means ignore groups, any other value limits the result by group id
2258 * @param bool $onlyactive consider only active enrolments in enabled plugins and time restrictions
2259 * @return array list($sql, $params)
bbbf2d40 2260 */
e922fe23
PS
2261function get_enrolled_sql(context $context, $withcapability = '', $groupid = 0, $onlyactive = false) {
2262 global $DB, $CFG;
4f0c2d00 2263
e922fe23
PS
2264 // use unique prefix just in case somebody makes some SQL magic with the result
2265 static $i = 0;
2266 $i++;
2267 $prefix = 'eu'.$i.'_';
4f0c2d00 2268
e922fe23
PS
2269 // first find the course context
2270 $coursecontext = $context->get_course_context();
4f0c2d00 2271
e922fe23 2272 $isfrontpage = ($coursecontext->instanceid == SITEID);
4f0c2d00 2273
e922fe23
PS
2274 $joins = array();
2275 $wheres = array();
2276 $params = array();
4f0c2d00 2277
e922fe23 2278 list($contextids, $contextpaths) = get_context_info_list($context);
4f0c2d00 2279
e922fe23
PS
2280 // get all relevant capability info for all roles
2281 if ($withcapability) {
2282 list($incontexts, $cparams) = $DB->get_in_or_equal($contextids, SQL_PARAMS_NAMED, 'ctx');
2283 $cparams['cap'] = $withcapability;
4f0c2d00 2284
e922fe23
PS
2285 $defs = array();
2286 $sql = "SELECT rc.id, rc.roleid, rc.permission, ctx.path
2287 FROM {role_capabilities} rc
2288 JOIN {context} ctx on rc.contextid = ctx.id
2289 WHERE rc.contextid $incontexts AND rc.capability = :cap";
2290 $rcs = $DB->get_records_sql($sql, $cparams);
2291 foreach ($rcs as $rc) {
2292 $defs[$rc->path][$rc->roleid] = $rc->permission;
df997f84 2293 }
4f0c2d00 2294
e922fe23
PS
2295 $access = array();
2296 if (!empty($defs)) {
2297 foreach ($contextpaths as $path) {
2298 if (empty($defs[$path])) {
2299 continue;
2300 }
2301 foreach($defs[$path] as $roleid => $perm) {
2302 if ($perm == CAP_PROHIBIT) {
2303 $access[$roleid] = CAP_PROHIBIT;
2304 continue;
2305 }
2306 if (!isset($access[$roleid])) {
2307 $access[$roleid] = (int)$perm;
2308 }
2309 }
df997f84
PS
2310 }
2311 }
4f0c2d00 2312
e922fe23
PS
2313 unset($defs);
2314
2315 // make lists of roles that are needed and prohibited
2316 $needed = array(); // one of these is enough
2317 $prohibited = array(); // must not have any of these
2318 foreach ($access as $roleid => $perm) {
2319 if ($perm == CAP_PROHIBIT) {
2320 unset($needed[$roleid]);
2321 $prohibited[$roleid] = true;
2322 } else if ($perm == CAP_ALLOW and empty($prohibited[$roleid])) {
2323 $needed[$roleid] = true;
df997f84
PS
2324 }
2325 }
4f0c2d00 2326
e922fe23
PS
2327 $defaultuserroleid = isset($CFG->defaultuserroleid) ? $CFG->defaultuserroleid : 0;
2328 $defaultfrontpageroleid = isset($CFG->defaultfrontpageroleid) ? $CFG->defaultfrontpageroleid : 0;
4f0c2d00 2329
e922fe23 2330 $nobody = false;
df997f84 2331
e922fe23
PS
2332 if ($isfrontpage) {
2333 if (!empty($prohibited[$defaultuserroleid]) or !empty($prohibited[$defaultfrontpageroleid])) {
2334 $nobody = true;
2335 } else if (!empty($needed[$defaultuserroleid]) or !empty($needed[$defaultfrontpageroleid])) {
2336 // everybody not having prohibit has the capability
2337 $needed = array();
2338 } else if (empty($needed)) {
2339 $nobody = true;
2340 }
2341 } else {
2342 if (!empty($prohibited[$defaultuserroleid])) {
2343 $nobody = true;
2344 } else if (!empty($needed[$defaultuserroleid])) {
2345 // everybody not having prohibit has the capability
2346 $needed = array();
2347 } else if (empty($needed)) {
2348 $nobody = true;
2349 }
2350 }
4f0c2d00 2351
e922fe23
PS
2352 if ($nobody) {
2353 // nobody can match so return some SQL that does not return any results
2354 $wheres[] = "1 = 2";
4f0c2d00 2355
e922fe23 2356 } else {
4f0c2d00 2357
e922fe23
PS
2358 if ($needed) {
2359 $ctxids = implode(',', $contextids);
2360 $roleids = implode(',', array_keys($needed));
2361 $joins[] = "JOIN {role_assignments} {$prefix}ra3 ON ({$prefix}ra3.userid = {$prefix}u.id AND {$prefix}ra3.roleid IN ($roleids) AND {$prefix}ra3.contextid IN ($ctxids))";
2362 }
4f0c2d00 2363
e922fe23
PS
2364 if ($prohibited) {
2365 $ctxids = implode(',', $contextids);
2366 $roleids = implode(',', array_keys($prohibited));
2367 $joins[] = "LEFT JOIN {role_assignments} {$prefix}ra4 ON ({$prefix}ra4.userid = {$prefix}u.id AND {$prefix}ra4.roleid IN ($roleids) AND {$prefix}ra4.contextid IN ($ctxids))";
2368 $wheres[] = "{$prefix}ra4.id IS NULL";
2369 }
4f0c2d00 2370
e922fe23
PS
2371 if ($groupid) {
2372 $joins[] = "JOIN {groups_members} {$prefix}gm ON ({$prefix}gm.userid = {$prefix}u.id AND {$prefix}gm.groupid = :{$prefix}gmid)";
2373 $params["{$prefix}gmid"] = $groupid;
2374 }
2375 }
4f0c2d00 2376
e922fe23
PS
2377 } else {
2378 if ($groupid) {
2379 $joins[] = "JOIN {groups_members} {$prefix}gm ON ({$prefix}gm.userid = {$prefix}u.id AND {$prefix}gm.groupid = :{$prefix}gmid)";
2380 $params["{$prefix}gmid"] = $groupid;
4f0c2d00 2381 }
e922fe23 2382 }
4f0c2d00 2383
e922fe23
PS
2384 $wheres[] = "{$prefix}u.deleted = 0 AND {$prefix}u.id <> :{$prefix}guestid";
2385 $params["{$prefix}guestid"] = $CFG->siteguest;
2386
2387 if ($isfrontpage) {
2388 // all users are "enrolled" on the frontpage
4f0c2d00 2389 } else {
e922fe23
PS
2390 $joins[] = "JOIN {user_enrolments} {$prefix}ue ON {$prefix}ue.userid = {$prefix}u.id";
2391 $joins[] = "JOIN {enrol} {$prefix}e ON ({$prefix}e.id = {$prefix}ue.enrolid AND {$prefix}e.courseid = :{$prefix}courseid)";
2392 $params[$prefix.'courseid'] = $coursecontext->instanceid;
2393
2394 if ($onlyactive) {
2395 $wheres[] = "{$prefix}ue.status = :{$prefix}active AND {$prefix}e.status = :{$prefix}enabled";
2396 $wheres[] = "{$prefix}ue.timestart < :{$prefix}now1 AND ({$prefix}ue.timeend = 0 OR {$prefix}ue.timeend > :{$prefix}now2)";
2397 $now = round(time(), -2); // rounding helps caching in DB
2398 $params = array_merge($params, array($prefix.'enabled'=>ENROL_INSTANCE_ENABLED,
2399 $prefix.'active'=>ENROL_USER_ACTIVE,
2400 $prefix.'now1'=>$now, $prefix.'now2'=>$now));
2401 }
4f0c2d00 2402 }
e922fe23
PS
2403
2404 $joins = implode("\n", $joins);
2405 $wheres = "WHERE ".implode(" AND ", $wheres);
2406
2407 $sql = "SELECT DISTINCT {$prefix}u.id
2408 FROM {user} {$prefix}u
2409 $joins
2410 $wheres";
2411
2412 return array($sql, $params);
4f0c2d00
PS
2413}
2414
2415/**
e922fe23 2416 * Returns list of users enrolled into course.
4f0c2d00 2417 *
f76249cc
PS
2418 * @package core_enrol
2419 * @category access
2420 *
e922fe23
PS
2421 * @param context $context
2422 * @param string $withcapability
2423 * @param int $groupid 0 means ignore groups, any other value limits the result by group id
2424 * @param string $userfields requested user record fields
2425 * @param string $orderby
2426 * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
2427 * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
38c1dd19 2428 * @param bool $onlyactive consider only active enrolments in enabled plugins and time restrictions
e922fe23 2429 * @return array of user records
4f0c2d00 2430 */
38c1dd19
RT
2431function get_enrolled_users(context $context, $withcapability = '', $groupid = 0, $userfields = 'u.*', $orderby = null,
2432 $limitfrom = 0, $limitnum = 0, $onlyactive = false) {
e922fe23 2433 global $DB;
5fd9e798 2434
38c1dd19 2435 list($esql, $params) = get_enrolled_sql($context, $withcapability, $groupid, $onlyactive);
e922fe23
PS
2436 $sql = "SELECT $userfields
2437 FROM {user} u
2438 JOIN ($esql) je ON je.id = u.id
2439 WHERE u.deleted = 0";
4f0c2d00 2440
e922fe23
PS
2441 if ($orderby) {
2442 $sql = "$sql ORDER BY $orderby";
4f0c2d00 2443 } else {
9695ff81
TH
2444 list($sort, $sortparams) = users_order_by_sql('u');
2445 $sql = "$sql ORDER BY $sort";
2446 $params = array_merge($params, $sortparams);
4f0c2d00
PS
2447 }
2448
e922fe23
PS
2449 return $DB->get_records_sql($sql, $params, $limitfrom, $limitnum);
2450}
4f0c2d00 2451
e922fe23
PS
2452/**
2453 * Counts list of users enrolled into course (as per above function)
2454 *
f76249cc
PS
2455 * @package core_enrol
2456 * @category access
2457 *
e922fe23
PS
2458 * @param context $context
2459 * @param string $withcapability
2460 * @param int $groupid 0 means ignore groups, any other value limits the result by group id
38c1dd19 2461 * @param bool $onlyactive consider only active enrolments in enabled plugins and time restrictions
e922fe23
PS
2462 * @return array of user records
2463 */
38c1dd19 2464function count_enrolled_users(context $context, $withcapability = '', $groupid = 0, $onlyactive = false) {
e922fe23 2465 global $DB;
4f0c2d00 2466
38c1dd19 2467 list($esql, $params) = get_enrolled_sql($context, $withcapability, $groupid, $onlyactive);
e922fe23
PS
2468 $sql = "SELECT count(u.id)
2469 FROM {user} u
2470 JOIN ($esql) je ON je.id = u.id
2471 WHERE u.deleted = 0";
2472
2473 return $DB->count_records_sql($sql, $params);
2474}
2475
2476/**
2477 * Loads the capability definitions for the component (from file).
2478 *
2479 * Loads the capability definitions for the component (from file). If no
2480 * capabilities are defined for the component, we simply return an empty array.
2481 *
f76249cc 2482 * @access private
e922fe23
PS
2483 * @param string $component full plugin name, examples: 'moodle', 'mod_forum'
2484 * @return array array of capabilities
2485 */
2486function load_capability_def($component) {
b0d1d941 2487 $defpath = core_component::get_component_directory($component).'/db/access.php';
e922fe23
PS
2488
2489 $capabilities = array();
2490 if (file_exists($defpath)) {
2491 require($defpath);
2492 if (!empty(${$component.'_capabilities'})) {
2493 // BC capability array name
2494 // since 2.0 we prefer $capabilities instead - it is easier to use and matches db/* files
99ddfdf4 2495 debugging('componentname_capabilities array is deprecated, please use $capabilities array only in access.php files');
e922fe23
PS
2496 $capabilities = ${$component.'_capabilities'};
2497 }
4f0c2d00
PS
2498 }
2499
e922fe23 2500 return $capabilities;
4f0c2d00
PS
2501}
2502
e922fe23
PS
2503/**
2504 * Gets the capabilities that have been cached in the database for this component.
2505 *
f76249cc 2506 * @access private
e922fe23
PS
2507 * @param string $component - examples: 'moodle', 'mod_forum'
2508 * @return array array of capabilities
2509 */
2510function get_cached_capabilities($component = 'moodle') {
2511 global $DB;
2512 return $DB->get_records('capabilities', array('component'=>$component));
2513}
4f0c2d00
PS
2514
2515/**
e922fe23 2516 * Returns default capabilities for given role archetype.
4f0c2d00 2517 *
e922fe23
PS
2518 * @param string $archetype role archetype
2519 * @return array
4f0c2d00 2520 */
e922fe23
PS
2521function get_default_capabilities($archetype) {
2522 global $DB;
4f0c2d00 2523
e922fe23
PS
2524 if (!$archetype) {
2525 return array();
4f0c2d00
PS
2526 }
2527
e922fe23
PS
2528 $alldefs = array();
2529 $defaults = array();
2530 $components = array();
2531 $allcaps = $DB->get_records('capabilities');
4f0c2d00 2532
e922fe23
PS
2533 foreach ($allcaps as $cap) {
2534 if (!in_array($cap->component, $components)) {
2535 $components[] = $cap->component;
2536 $alldefs = array_merge($alldefs, load_capability_def($cap->component));
2537 }
2538 }
2539 foreach($alldefs as $name=>$def) {
2540 // Use array 'archetypes if available. Only if not specified, use 'legacy'.
2541 if (isset($def['archetypes'])) {
2542 if (isset($def['archetypes'][$archetype])) {
2543 $defaults[$name] = $def['archetypes'][$archetype];
2544 }
2545 // 'legacy' is for backward compatibility with 1.9 access.php
2546 } else {
2547 if (isset($def['legacy'][$archetype])) {
2548 $defaults[$name] = $def['legacy'][$archetype];
2549 }
2550 }
4f0c2d00
PS
2551 }
2552
e922fe23 2553 return $defaults;
4f0c2d00
PS
2554}
2555
5e72efd4
PS
2556/**
2557 * Return default roles that can be assigned, overridden or switched
2558 * by give role archetype.
2559 *
2560 * @param string $type assign|override|switch
2561 * @param string $archetype
2562 * @return array of role ids
2563 */
2564function get_default_role_archetype_allows($type, $archetype) {
2565 global $DB;
2566
2567 if (empty($archetype)) {
2568 return array();
2569 }
2570
2571 $roles = $DB->get_records('role');
2572 $archetypemap = array();
2573 foreach ($roles as $role) {
2574 if ($role->archetype) {
2575 $archetypemap[$role->archetype][$role->id] = $role->id;
2576 }
2577 }
2578
2579 $defaults = array(
2580 'assign' => array(
2581 'manager' => array('manager', 'coursecreator', 'editingteacher', 'teacher', 'student'),
2582 'coursecreator' => array(),
2583 'editingteacher' => array('teacher', 'student'),
2584 'teacher' => array(),
2585 'student' => array(),
2586 'guest' => array(),
2587 'user' => array(),
2588 'frontpage' => array(),
2589 ),
2590 'override' => array(
2591 'manager' => array('manager', 'coursecreator', 'editingteacher', 'teacher', 'student', 'guest', 'user', 'frontpage'),
2592 'coursecreator' => array(),
2593 'editingteacher' => array('teacher', 'student', 'guest'),
2594 'teacher' => array(),
2595 'student' => array(),
2596 'guest' => array(),
2597 'user' => array(),
2598 'frontpage' => array(),
2599 ),
2600 'switch' => array(
2601 'manager' => array('editingteacher', 'teacher', 'student', 'guest'),
2602 'coursecreator' => array(),
2603 'editingteacher' => array('teacher', 'student', 'guest'),
2604 'teacher' => array('student', 'guest'),
2605 'student' => array(),
2606 'guest' => array(),
2607 'user' => array(),
2608 'frontpage' => array(),
2609 ),
2610 );
2611
2612 if (!isset($defaults[$type][$archetype])) {
2613 debugging("Unknown type '$type'' or archetype '$archetype''");
2614 return array();
2615 }
2616
2617 $return = array();
2618 foreach ($defaults[$type][$archetype] as $at) {
2619 if (isset($archetypemap[$at])) {
2620 foreach ($archetypemap[$at] as $roleid) {
2621 $return[$roleid] = $roleid;
2622 }
2623 }
2624 }
2625
2626 return $return;
2627}
2628
4f0c2d00 2629/**
e922fe23
PS
2630 * Reset role capabilities to default according to selected role archetype.
2631 * If no archetype selected, removes all capabilities.
4f0c2d00 2632 *
0f1882ed 2633 * This applies to capabilities that are assigned to the role (that you could
2634 * edit in the 'define roles' interface), and not to any capability overrides
2635 * in different locations.
2636 *
2637 * @param int $roleid ID of role to reset capabilities for
4f0c2d00 2638 */
e922fe23
PS
2639function reset_role_capabilities($roleid) {
2640 global $DB;
4f0c2d00 2641
e922fe23
PS
2642 $role = $DB->get_record('role', array('id'=>$roleid), '*', MUST_EXIST);
2643 $defaultcaps = get_default_capabilities($role->archetype);
4f0c2d00 2644
e922fe23 2645 $systemcontext = context_system::instance();
df997f84 2646
3978da9e 2647 $DB->delete_records('role_capabilities',
0f1882ed 2648 array('roleid' => $roleid, 'contextid' => $systemcontext->id));
4f0c2d00 2649
e922fe23
PS
2650 foreach($defaultcaps as $cap=>$permission) {
2651 assign_capability($cap, $permission, $roleid, $systemcontext->id);
4f0c2d00 2652 }
0f1882ed 2653
2654 // Mark the system context dirty.
2655 context_system::instance()->mark_dirty();
4f0c2d00
PS
2656}
2657
ed1d72ea 2658/**
e922fe23
PS
2659 * Updates the capabilities table with the component capability definitions.
2660 * If no parameters are given, the function updates the core moodle
2661 * capabilities.
ed1d72ea 2662 *
e922fe23
PS
2663 * Note that the absence of the db/access.php capabilities definition file
2664 * will cause any stored capabilities for the component to be removed from
2665 * the database.
ed1d72ea 2666 *
f76249cc 2667 * @access private
e922fe23
PS
2668 * @param string $component examples: 'moodle', 'mod/forum', 'block/quiz_results'
2669 * @return boolean true if success, exception in case of any problems
ed1d72ea 2670 */
e922fe23
PS
2671function update_capabilities($component = 'moodle') {
2672 global $DB, $OUTPUT;
ed1d72ea 2673
e922fe23 2674 $storedcaps = array();
ed1d72ea 2675
e922fe23
PS
2676 $filecaps = load_capability_def($component);
2677 foreach($filecaps as $capname=>$unused) {
2678 if (!preg_match('|^[a-z]+/[a-z_0-9]+:[a-z_0-9]+$|', $capname)) {
2679 debugging("Coding problem: Invalid capability name '$capname', use 'clonepermissionsfrom' field for migration.");
2680 }
ed1d72ea
SH
2681 }
2682
e922fe23
PS
2683 $cachedcaps = get_cached_capabilities($component);
2684 if ($cachedcaps) {
2685 foreach ($cachedcaps as $cachedcap) {
2686 array_push($storedcaps, $cachedcap->name);
2687 // update risk bitmasks and context levels in existing capabilities if needed
2688 if (array_key_exists($cachedcap->name, $filecaps)) {
2689 if (!array_key_exists('riskbitmask', $filecaps[$cachedcap->name])) {
2690 $filecaps[$cachedcap->name]['riskbitmask'] = 0; // no risk if not specified
2691 }
2692 if ($cachedcap->captype != $filecaps[$cachedcap->name]['captype']) {
2693 $updatecap = new stdClass();
2694 $updatecap->id = $cachedcap->id;
2695 $updatecap->captype = $filecaps[$cachedcap->name]['captype'];
2696 $DB->update_record('capabilities', $updatecap);
2697 }
2698 if ($cachedcap->riskbitmask != $filecaps[$cachedcap->name]['riskbitmask']) {
2699 $updatecap = new stdClass();
2700 $updatecap->id = $cachedcap->id;
2701 $updatecap->riskbitmask = $filecaps[$cachedcap->name]['riskbitmask'];
2702 $DB->update_record('capabilities', $updatecap);
2703 }
ed1d72ea 2704
e922fe23
PS
2705 if (!array_key_exists('contextlevel', $filecaps[$cachedcap->name])) {
2706 $filecaps[$cachedcap->name]['contextlevel'] = 0; // no context level defined
2707 }
2708 if ($cachedcap->contextlevel != $filecaps[$cachedcap->name]['contextlevel']) {
2709 $updatecap = new stdClass();
2710 $updatecap->id = $cachedcap->id;
2711 $updatecap->contextlevel = $filecaps[$cachedcap->name]['contextlevel'];
2712 $DB->update_record('capabilities', $updatecap);
2713 }
ed1d72ea 2714 }
e922fe23
PS
2715 }
2716 }
2717
2718 // Are there new capabilities in the file definition?
2719 $newcaps = array();
2720
2721 foreach ($filecaps as $filecap => $def) {
2722 if (!$storedcaps ||
2723 ($storedcaps && in_array($filecap, $storedcaps) === false)) {
2724 if (!array_key_exists('riskbitmask', $def)) {
2725 $def['riskbitmask'] = 0; // no risk if not specified
ed1d72ea 2726 }
e922fe23 2727 $newcaps[$filecap] = $def;
ed1d72ea
SH
2728 }
2729 }
e922fe23 2730 // Add new capabilities to the stored definition.
a36e170f 2731 $existingcaps = $DB->get_records_menu('capabilities', array(), 'id', 'id, name');
e922fe23
PS
2732 foreach ($newcaps as $capname => $capdef) {
2733 $capability = new stdClass();
2734 $capability->name = $capname;
2735 $capability->captype = $capdef['captype'];
2736 $capability->contextlevel = $capdef['contextlevel'];
2737 $capability->component = $component;
2738 $capability->riskbitmask = $capdef['riskbitmask'];
ed1d72ea 2739
e922fe23
PS
2740 $DB->insert_record('capabilities', $capability, false);
2741
a36e170f 2742 if (isset($capdef['clonepermissionsfrom']) && in_array($capdef['clonepermissionsfrom'], $existingcaps)){
e922fe23
PS
2743 if ($rolecapabilities = $DB->get_records('role_capabilities', array('capability'=>$capdef['clonepermissionsfrom']))){
2744 foreach ($rolecapabilities as $rolecapability){
2745 //assign_capability will update rather than insert if capability exists
2746 if (!assign_capability($capname, $rolecapability->permission,
2747 $rolecapability->roleid, $rolecapability->contextid, true)){
2748 echo $OUTPUT->notification('Could not clone capabilities for '.$capname);
2749 }
2750 }
2751 }
2752 // we ignore archetype key if we have cloned permissions
2753 } else if (isset($capdef['archetypes']) && is_array($capdef['archetypes'])) {
2754 assign_legacy_capabilities($capname, $capdef['archetypes']);
2755 // 'legacy' is for backward compatibility with 1.9 access.php
2756 } else if (isset($capdef['legacy']) && is_array($capdef['legacy'])) {
2757 assign_legacy_capabilities($capname, $capdef['legacy']);
ed1d72ea
SH
2758 }
2759 }
e922fe23
PS
2760 // Are there any capabilities that have been removed from the file
2761 // definition that we need to delete from the stored capabilities and
2762 // role assignments?
2763 capabilities_cleanup($component, $filecaps);
2764
2765 // reset static caches
2766 accesslib_clear_all_caches(false);
2767
2768 return true;
ed1d72ea
SH
2769}
2770
4f0c2d00 2771/**
e922fe23
PS
2772 * Deletes cached capabilities that are no longer needed by the component.
2773 * Also unassigns these capabilities from any roles that have them.
c2ca2d8e 2774 * NOTE: this function is called from lib/db/upgrade.php
df997f84 2775 *
f76249cc 2776 * @access private
e922fe23
PS
2777 * @param string $component examples: 'moodle', 'mod_forum', 'block_quiz_results'
2778 * @param array $newcapdef array of the new capability definitions that will be
2779 * compared with the cached capabilities
2780 * @return int number of deprecated capabilities that have been removed
4f0c2d00 2781 */
e922fe23
PS
2782function capabilities_cleanup($component, $newcapdef = null) {
2783 global $DB;
4f0c2d00 2784
e922fe23 2785 $removedcount = 0;
4f0c2d00 2786
e922fe23
PS
2787 if ($cachedcaps = get_cached_capabilities($component)) {
2788 foreach ($cachedcaps as $cachedcap) {
2789 if (empty($newcapdef) ||
2790 array_key_exists($cachedcap->name, $newcapdef) === false) {
4f0c2d00 2791
e922fe23
PS
2792 // Remove from capabilities cache.
2793 $DB->delete_records('capabilities', array('name'=>$cachedcap->name));
2794 $removedcount++;
2795 // Delete from roles.
2796 if ($roles = get_roles_with_capability($cachedcap->name)) {
2797 foreach($roles as $role) {
2798 if (!unassign_capability($cachedcap->name, $role->id)) {
2799 print_error('cannotunassigncap', 'error', '', (object)array('cap'=>$cachedcap->name, 'role'=>$role->name));
2800 }
2801 }
2802 }
2803 } // End if.
2804 }
2805 }
2806 return $removedcount;
2807}
2808
e922fe23
PS
2809/**
2810 * Returns an array of all the known types of risk
2811 * The array keys can be used, for example as CSS class names, or in calls to
2812 * print_risk_icon. The values are the corresponding RISK_ constants.
2813 *
2814 * @return array all the known types of risk.
2815 */
2816function get_all_risks() {
2817 return array(
2818 'riskmanagetrust' => RISK_MANAGETRUST,
2819 'riskconfig' => RISK_CONFIG,
2820 'riskxss' => RISK_XSS,
2821 'riskpersonal' => RISK_PERSONAL,
2822 'riskspam' => RISK_SPAM,
2823 'riskdataloss' => RISK_DATALOSS,
2824 );
2825}
2826
2827/**
2828 * Return a link to moodle docs for a given capability name
2829 *
f76249cc 2830 * @param stdClass $capability a capability - a row from the mdl_capabilities table.
e922fe23
PS
2831 * @return string the human-readable capability name as a link to Moodle Docs.
2832 */
2833function get_capability_docs_link($capability) {
2834 $url = get_docs_url('Capabilities/' . $capability->name);
2835 return '<a onclick="this.target=\'docspopup\'" href="' . $url . '">' . get_capability_string($capability->name) . '</a>';
2836}
2837
2838/**
2839 * This function pulls out all the resolved capabilities (overrides and
2840 * defaults) of a role used in capability overrides in contexts at a given
2841 * context.
2842 *
e922fe23 2843 * @param int $roleid
34223e03 2844 * @param context $context
e922fe23 2845 * @param string $cap capability, optional, defaults to ''
34223e03 2846 * @return array Array of capabilities
e922fe23
PS
2847 */
2848function role_context_capabilities($roleid, context $context, $cap = '') {
2849 global $DB;
2850
2851 $contexts = $context->get_parent_context_ids(true);
2852 $contexts = '('.implode(',', $contexts).')';
2853
2854 $params = array($roleid);
2855
2856 if ($cap) {
2857 $search = " AND rc.capability = ? ";
2858 $params[] = $cap;
2859 } else {
2860 $search = '';
2861 }
2862
2863 $sql = "SELECT rc.*
2864 FROM {role_capabilities} rc, {context} c
2865 WHERE rc.contextid in $contexts
2866 AND rc.roleid = ?
2867 AND rc.contextid = c.id $search
2868 ORDER BY c.contextlevel DESC, rc.capability DESC";
2869
2870 $capabilities = array();
2871
2872 if ($records = $DB->get_records_sql($sql, $params)) {
2873 // We are traversing via reverse order.
2874 foreach ($records as $record) {
2875 // If not set yet (i.e. inherit or not set at all), or currently we have a prohibit
2876 if (!isset($capabilities[$record->capability]) || $record->permission<-500) {
2877 $capabilities[$record->capability] = $record->permission;
2878 }
2879 }
2880 }
2881 return $capabilities;
2882}
2883
2884/**
2885 * Constructs array with contextids as first parameter and context paths,
2886 * in both cases bottom top including self.
2887 *
f76249cc 2888 * @access private
e922fe23
PS
2889 * @param context $context
2890 * @return array
2891 */
2892function get_context_info_list(context $context) {
2893 $contextids = explode('/', ltrim($context->path, '/'));
2894 $contextpaths = array();
2895 $contextids2 = $contextids;
2896 while ($contextids2) {
2897 $contextpaths[] = '/' . implode('/', $contextids2);
2898 array_pop($contextids2);
2899 }
2900 return array($contextids, $contextpaths);
2901}
2902
2903/**
2904 * Check if context is the front page context or a context inside it
2905 *
2906 * Returns true if this context is the front page context, or a context inside it,
2907 * otherwise false.
2908 *
2909 * @param context $context a context object.
2910 * @return bool
2911 */
2912function is_inside_frontpage(context $context) {
2913 $frontpagecontext = context_course::instance(SITEID);
2914 return strpos($context->path . '/', $frontpagecontext->path . '/') === 0;
2915}
2916
2917/**
2918 * Returns capability information (cached)
2919 *
2920 * @param string $capabilityname
f76249cc 2921 * @return stdClass or null if capability not found
e922fe23
PS
2922 */
2923function get_capability_info($capabilityname) {
2924 global $ACCESSLIB_PRIVATE, $DB; // one request per page only
2925
2926 //TODO: MUC - this could be cached in shared memory, it would eliminate 1 query per page
2927
2928 if (empty($ACCESSLIB_PRIVATE->capabilities)) {
2929 $ACCESSLIB_PRIVATE->capabilities = array();
2930 $caps = $DB->get_records('capabilities', array(), 'id, name, captype, riskbitmask');
2931 foreach ($caps as $cap) {
2932 $capname = $cap->name;
2933 unset($cap->id);
2934 unset($cap->name);
2935 $cap->riskbitmask = (int)$cap->riskbitmask;
2936 $ACCESSLIB_PRIVATE->capabilities[$capname] = $cap;
2937 }
2938 }
2939
2940 return isset($ACCESSLIB_PRIVATE->capabilities[$capabilityname]) ? $ACCESSLIB_PRIVATE->capabilities[$capabilityname] : null;
2941}
2942
2943/**
2944 * Returns the human-readable, translated version of the capability.
2945 * Basically a big switch statement.
2946 *
2947 * @param string $capabilityname e.g. mod/choice:readresponses
2948 * @return string
2949 */
2950function get_capability_string($capabilityname) {
2951
2952 // Typical capability name is 'plugintype/pluginname:capabilityname'
2953 list($type, $name, $capname) = preg_split('|[/:]|', $capabilityname);
2954
2955 if ($type === 'moodle') {
2956 $component = 'core_role';
2957 } else if ($type === 'quizreport') {
2958 //ugly hack!!
2959 $component = 'quiz_'.$name;
2960 } else {
2961 $component = $type.'_'.$name;
2962 }
2963
2964 $stringname = $name.':'.$capname;
2965
2966 if ($component === 'core_role' or get_string_manager()->string_exists($stringname, $component)) {
2967 return get_string($stringname, $component);
2968 }
2969
b0d1d941 2970 $dir = core_component::get_component_directory($component);
e922fe23
PS
2971 if (!file_exists($dir)) {
2972 // plugin broken or does not exist, do not bother with printing of debug message
2973 return $capabilityname.' ???';
2974 }
2975
2976 // something is wrong in plugin, better print debug
2977 return get_string($stringname, $component);
2978}
2979
2980/**
2981 * This gets the mod/block/course/core etc strings.
2982 *
2983 * @param string $component
2984 * @param int $contextlevel
2985 * @return string|bool String is success, false if failed
2986 */
2987function get_component_string($component, $contextlevel) {
2988
2989 if ($component === 'moodle' or $component === 'core') {
2990 switch ($contextlevel) {
78c12cdb 2991 // TODO MDL-46123: this should probably use context level names instead
e922fe23
PS
2992 case CONTEXT_SYSTEM: return get_string('coresystem');
2993 case CONTEXT_USER: return get_string('users');
2994 case CONTEXT_COURSECAT: return get_string('categories');
2995 case CONTEXT_COURSE: return get_string('course');
2996 case CONTEXT_MODULE: return get_string('activities');
2997 case CONTEXT_BLOCK: return get_string('block');
2998 default: print_error('unknowncontext');
2999 }
3000 }
3001
56da374e 3002 list($type, $name) = core_component::normalize_component($component);
1c74b260 3003 $dir = core_component::get_plugin_directory($type, $name);
e922fe23
PS
3004 if (!file_exists($dir)) {
3005 // plugin not installed, bad luck, there is no way to find the name
3006 return $component.' ???';
3007 }
3008
3009 switch ($type) {
78c12cdb 3010 // TODO MDL-46123: this is really hacky and should be improved.
e922fe23
PS
3011 case 'quiz': return get_string($name.':componentname', $component);// insane hack!!!
3012 case 'repository': return get_string('repository', 'repository').': '.get_string('pluginname', $component);
3013 case 'gradeimport': return get_string('gradeimport', 'grades').': '.get_string('pluginname', $component);
3014 case 'gradeexport': return get_string('gradeexport', 'grades').': '.get_string('pluginname', $component);
3015 case 'gradereport': return get_string('gradereport', 'grades').': '.get_string('pluginname', $component);
3016 case 'webservice': return get_string('webservice', 'webservice').': '.get_string('pluginname', $component);
3017 case 'block': return get_string('block').': '.get_string('pluginname', basename($component));
3018 case 'mod':
3019 if (get_string_manager()->string_exists('pluginname', $component)) {
3020 return get_string('activity').': '.get_string('pluginname', $component);
3021 } else {
3022 return get_string('activity').': '.get_string('modulename', $component);
3023 }
3024 default: return get_string('pluginname', $component);
3025 }
3026}
3027
3028/**
3029 * Gets the list of roles assigned to this context and up (parents)
3030 * from the list of roles that are visible on user profile page
3031 * and participants page.
3032 *
3033 * @param context $context
3034 * @return array
3035 */
3036function get_profile_roles(context $context) {
3037 global $CFG, $DB;
3038
3039 if (empty($CFG->profileroles)) {
3040 return array();
3041 }
3042
3043 list($rallowed, $params) = $DB->get_in_or_equal(explode(',', $CFG->profileroles), SQL_PARAMS_NAMED, 'a');
3044 list($contextlist, $cparams) = $DB->get_in_or_equal($context->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'p');
3045 $params = array_merge($params, $cparams);
3046
c52551dc
PS
3047 if ($coursecontext = $context->get_course_context(false)) {
3048 $params['coursecontext'] = $coursecontext->id;
3049 } else {
3050 $params['coursecontext'] = 0;
3051 }
3052
3053 $sql = "SELECT DISTINCT r.id, r.name, r.shortname, r.sortorder, rn.name AS coursealias
e922fe23 3054 FROM {role_assignments} ra, {role} r
c52551dc 3055 LEFT JOIN {role_names} rn ON (rn.contextid = :coursecontext AND rn.roleid = r.id)
e922fe23
PS
3056 WHERE r.id = ra.roleid
3057 AND ra.contextid $contextlist
3058 AND r.id $rallowed
3059 ORDER BY r.sortorder ASC";
3060
3061 return $DB->get_records_sql($sql, $params);
3062}
3063
3064/**
3065 * Gets the list of roles assigned to this context and up (parents)
3066 *
3067 * @param context $context
3068 * @return array
3069 */
3070function get_roles_used_in_context(context $context) {
3071 global $DB;
3072
c52551dc
PS
3073 list($contextlist, $params) = $DB->get_in_or_equal($context->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'cl');
3074
3075 if ($coursecontext = $context->get_course_context(false)) {
3076 $params['coursecontext'] = $coursecontext->id;
3077 } else {
3078 $params['coursecontext'] = 0;
3079 }
e922fe23 3080
c52551dc 3081 $sql = "SELECT DISTINCT r.id, r.name, r.shortname, r.sortorder, rn.name AS coursealias
e922fe23 3082 FROM {role_assignments} ra, {role} r
c52551dc 3083 LEFT JOIN {role_names} rn ON (rn.contextid = :coursecontext AND rn.roleid = r.id)
e922fe23
PS
3084 WHERE r.id = ra.roleid
3085 AND ra.contextid $contextlist
3086 ORDER BY r.sortorder ASC";
3087
3088 return $DB->get_records_sql($sql, $params);
3089}
3090
3091/**
3092 * This function is used to print roles column in user profile page.
3093 * It is using the CFG->profileroles to limit the list to only interesting roles.
3094 * (The permission tab has full details of user role assignments.)
3095 *
3096 * @param int $userid
3097 * @param int $courseid
3098 * @return string
3099 */
3100function get_user_roles_in_course($userid, $courseid) {
3101 global $CFG, $DB;
3102
3103 if (empty($CFG->profileroles)) {
3104 return '';
3105 }
3106
3107 if ($courseid == SITEID) {
3108 $context = context_system::instance();
3109 } else {
3110 $context = context_course::instance($courseid);
3111 }
3112
3113 if (empty($CFG->profileroles)) {
3114 return array();
3115 }
3116
3117 list($rallowed, $params) = $DB->get_in_or_equal(explode(',', $CFG->profileroles), SQL_PARAMS_NAMED, 'a');
3118 list($contextlist, $cparams) = $DB->get_in_or_equal($context->get_parent_context_ids(true), SQL_PARAMS_NAMED, 'p');
3119 $params = array_merge($params, $cparams);
3120
c52551dc
PS
3121 if ($coursecontext = $context->get_course_context(false)) {
3122 $params['coursecontext'] = $coursecontext->id;
3123 } else {
3124 $params['coursecontext'] = 0;
3125 }
3126
3127 $sql = "SELECT DISTINCT r.id, r.name, r.shortname, r.sortorder, rn.name AS coursealias
e922fe23 3128 FROM {role_assignments} ra, {role} r
c52551dc 3129 LEFT JOIN {role_names} rn ON (rn.contextid = :coursecontext AND rn.roleid = r.id)
e922fe23
PS
3130 WHERE r.id = ra.roleid
3131 AND ra.contextid $contextlist
3132 AND r.id $rallowed
3133 AND ra.userid = :userid
3134 ORDER BY r.sortorder ASC";
3135 $params['userid'] = $userid;
3136
3137 $rolestring = '';
3138
3139 if ($roles = $DB->get_records_sql($sql, $params)) {
c52551dc 3140 $rolenames = role_fix_names($roles, $context, ROLENAME_ALIAS, true); // Substitute aliases
e922fe23
PS
3141
3142 foreach ($rolenames as $roleid => $rolename) {
3143 $rolenames[$roleid] = '<a href="'.$CFG->wwwroot.'/user/index.php?contextid='.$context->id.'&amp;roleid='.$roleid.'">'.$rolename.'</a>';
3144 }
3145 $rolestring = implode(',', $rolenames);
3146 }
3147
3148 return $rolestring;
3149}
3150
3151/**
3152 * Checks if a user can assign users to a particular role in this context
3153 *
3154 * @param context $context
3155 * @param int $targetroleid - the id of the role you want to assign users to
3156 * @return boolean
3157 */
3158function user_can_assign(context $context, $targetroleid) {
3159 global $DB;
3160
3370f216
AG
3161 // First check to see if the user is a site administrator.
3162 if (is_siteadmin()) {
3163 return true;
3164 }
3165
3166 // Check if user has override capability.
3167 // If not return false.
e922fe23
PS
3168 if (!has_capability('moodle/role:assign', $context)) {
3169 return false;
3170 }
3171 // pull out all active roles of this user from this context(or above)
3172 if ($userroles = get_user_roles($context)) {
3173 foreach ($userroles as $userrole) {
3174 // if any in the role_allow_override table, then it's ok
3175 if ($DB->get_record('role_allow_assign', array('roleid'=>$userrole->roleid, 'allowassign'=>$targetroleid))) {
3176 return true;
3177 }
3178 }
3179 }
3180
3181 return false;
3182}
3183
3184/**
3185 * Returns all site roles in correct sort order.
3186 *
fa0ad435
PS
3187 * Note: this method does not localise role names or descriptions,
3188 * use role_get_names() if you need role names.
3189 *
c52551dc
PS
3190 * @param context $context optional context for course role name aliases
3191 * @return array of role records with optional coursealias property
e922fe23 3192 */
c52551dc 3193function get_all_roles(context $context = null) {
e922fe23 3194 global $DB;
c52551dc
PS
3195
3196 if (!$context or !$coursecontext = $context->get_course_context(false)) {
3197 $coursecontext = null;
3198 }
3199
3200 if ($coursecontext) {
3201 $sql = "SELECT r.*, rn.name AS coursealias
3202 FROM {role} r
3203 LEFT JOIN {role_names} rn ON (rn.contextid = :coursecontext AND rn.roleid = r.id)
3204 ORDER BY r.sortorder ASC";
3205 return $DB->get_records_sql($sql, array('coursecontext'=>$coursecontext->id));
3206
3207 } else {
3208 return $DB->get_records('role', array(), 'sortorder ASC');
3209 }
e922fe23
PS
3210}
3211
3212/**
3213 * Returns roles of a specified archetype
3214 *
3215 * @param string $archetype
3216 * @return array of full role records
3217 */
3218function get_archetype_roles($archetype) {
3219 global $DB;
3220 return $DB->get_records('role', array('archetype'=>$archetype), 'sortorder ASC');
3221}