Merge branch 'MDL-45339-master' of git://github.com/xow/moodle
[moodle.git] / lib / moodlelib.php
CommitLineData
0d0a8bf6 1<?php
6759ad2f 2// This file is part of Moodle - http://moodle.org/
3//
0d0a8bf6 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.
6759ad2f 13//
0d0a8bf6 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/>.
65ccdd8c 16
7cf1c7bd 17/**
89dcb99d 18 * moodlelib.php - Moodle main library
7cf1c7bd 19 *
20 * Main library file of miscellaneous general-purpose Moodle functions.
21 * Other main libraries:
8c3dba73 22 * - weblib.php - functions that produce web output
23 * - datalib.php - functions that access the database
0d0a8bf6 24 *
78bfb562
PS
25 * @package core
26 * @subpackage lib
27 * @copyright 1999 onwards Martin Dougiamas http://dougiamas.com
28 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
7cf1c7bd 29 */
e1ecf0a0 30
78bfb562
PS
31defined('MOODLE_INTERNAL') || die();
32
ac7af0da 33// CONSTANTS (Encased in phpdoc proper comments).
f374fb10 34
ac7af0da 35// Date and time constants.
5602f7cf 36/**
37 * Time constant - the number of seconds in a year
38 */
5602f7cf 39define('YEARSECS', 31536000);
40
7a5672c9 41/**
2f87145b 42 * Time constant - the number of seconds in a week
7a5672c9 43 */
361855e6 44define('WEEKSECS', 604800);
2f87145b 45
46/**
47 * Time constant - the number of seconds in a day
48 */
7a5672c9 49define('DAYSECS', 86400);
2f87145b 50
51/**
52 * Time constant - the number of seconds in an hour
53 */
7a5672c9 54define('HOURSECS', 3600);
2f87145b 55
56/**
57 * Time constant - the number of seconds in a minute
58 */
7a5672c9 59define('MINSECS', 60);
2f87145b 60
61/**
62 * Time constant - the number of minutes in a day
63 */
7a5672c9 64define('DAYMINS', 1440);
2f87145b 65
66/**
67 * Time constant - the number of minutes in an hour
68 */
7a5672c9 69define('HOURMINS', 60);
f9903ed0 70
ac7af0da
SH
71// Parameter constants - every call to optional_param(), required_param()
72// or clean_param() should have a specified type of parameter.
03b31ea3 73
e0d346ff 74/**
03b31ea3 75 * PARAM_ALPHA - contains only english ascii letters a-zA-Z.
e0d346ff 76 */
03b31ea3 77define('PARAM_ALPHA', 'alpha');
bbd3f2c4 78
79/**
03b31ea3 80 * PARAM_ALPHAEXT the same contents as PARAM_ALPHA plus the chars in quotes: "_-" allowed
81 * NOTE: originally this allowed "/" too, please use PARAM_SAFEPATH if "/" needed
bbd3f2c4 82 */
03b31ea3 83define('PARAM_ALPHAEXT', 'alphaext');
bbd3f2c4 84
85/**
03b31ea3 86 * PARAM_ALPHANUM - expected numbers and letters only.
bbd3f2c4 87 */
03b31ea3 88define('PARAM_ALPHANUM', 'alphanum');
bbd3f2c4 89
90/**
03b31ea3 91 * PARAM_ALPHANUMEXT - expected numbers, letters only and _-.
bbd3f2c4 92 */
03b31ea3 93define('PARAM_ALPHANUMEXT', 'alphanumext');
bbd3f2c4 94
9dae915a 95/**
03b31ea3 96 * PARAM_AUTH - actually checks to make sure the string is a valid auth plugin
6e73ae10 97 */
03b31ea3 98define('PARAM_AUTH', 'auth');
6e73ae10 99
100/**
03b31ea3 101 * PARAM_BASE64 - Base 64 encoded format
9dae915a 102 */
03b31ea3 103define('PARAM_BASE64', 'base64');
9dae915a 104
bbd3f2c4 105/**
03b31ea3 106 * PARAM_BOOL - converts input into 0 or 1, use for switches in forms and urls.
bbd3f2c4 107 */
03b31ea3 108define('PARAM_BOOL', 'bool');
bbd3f2c4 109
110/**
03b31ea3 111 * PARAM_CAPABILITY - A capability name, like 'moodle/role:manage'. Actually
efb8c375 112 * checked against the list of capabilities in the database.
6e73ae10 113 */
03b31ea3 114define('PARAM_CAPABILITY', 'capability');
6e73ae10 115
116/**
2d2018ab
TH
117 * PARAM_CLEANHTML - cleans submitted HTML code. Note that you almost never want
118 * to use this. The normal mode of operation is to use PARAM_RAW when recieving
119 * the input (required/optional_param or formslib) and then sanitse the HTML
120 * using format_text on output. This is for the rare cases when you want to
121 * sanitise the HTML on input. This cleaning may also fix xhtml strictness.
bbd3f2c4 122 */
03b31ea3 123define('PARAM_CLEANHTML', 'cleanhtml');
bbd3f2c4 124
79f1d953 125/**
126 * PARAM_EMAIL - an email address following the RFC
127 */
128define('PARAM_EMAIL', 'email');
129
bbd3f2c4 130/**
03b31ea3 131 * PARAM_FILE - safe file name, all dangerous chars are stripped, protects against XSS, SQL injections and directory traversals
bbd3f2c4 132 */
03b31ea3 133define('PARAM_FILE', 'file');
6e73ae10 134
135/**
03b31ea3 136 * PARAM_FLOAT - a real/floating point number.
7f5f3844
TH
137 *
138 * Note that you should not use PARAM_FLOAT for numbers typed in by the user.
139 * It does not work for languages that use , as a decimal separator.
140 * Instead, do something like
141 * $rawvalue = required_param('name', PARAM_RAW);
142 * // ... other code including require_login, which sets current lang ...
143 * $realvalue = unformat_float($rawvalue);
144 * // ... then use $realvalue
6e73ae10 145 */
03b31ea3 146define('PARAM_FLOAT', 'float');
6e73ae10 147
148/**
03b31ea3 149 * PARAM_HOST - expected fully qualified domain name (FQDN) or an IPv4 dotted quad (IP address)
150 */
151define('PARAM_HOST', 'host');
152
153/**
154 * PARAM_INT - integers only, use when expecting only numbers.
6e73ae10 155 */
03b31ea3 156define('PARAM_INT', 'int');
157
158/**
159 * PARAM_LANG - checks to see if the string is a valid installed language in the current site.
160 */
161define('PARAM_LANG', 'lang');
162
163/**
ac7af0da
SH
164 * PARAM_LOCALURL - expected properly formatted URL as well as one that refers to the local server itself. (NOT orthogonal to the
165 * others! Implies PARAM_URL!)
03b31ea3 166 */
167define('PARAM_LOCALURL', 'localurl');
bbd3f2c4 168
169/**
c59733ef 170 * PARAM_NOTAGS - all html tags are stripped from the text. Do not abuse this type.
bbd3f2c4 171 */
03b31ea3 172define('PARAM_NOTAGS', 'notags');
bbd3f2c4 173
6e73ae10 174/**
ac7af0da
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175 * PARAM_PATH - safe relative path name, all dangerous chars are stripped, protects against XSS, SQL injections and directory
176 * traversals note: the leading slash is not removed, window drive letter is not allowed
31f26796 177 */
03b31ea3 178define('PARAM_PATH', 'path');
31f26796 179
6e73ae10 180/**
03b31ea3 181 * PARAM_PEM - Privacy Enhanced Mail format
c4ea5e78 182 */
03b31ea3 183define('PARAM_PEM', 'pem');
c4ea5e78 184
bbd3f2c4 185/**
03b31ea3 186 * PARAM_PERMISSION - A permission, one of CAP_INHERIT, CAP_ALLOW, CAP_PREVENT or CAP_PROHIBIT.
bbd3f2c4 187 */
03b31ea3 188define('PARAM_PERMISSION', 'permission');
bbd3f2c4 189
bed79931 190/**
78fcdb5f 191 * PARAM_RAW specifies a parameter that is not cleaned/processed in any way except the discarding of the invalid utf-8 characters
bed79931 192 */
03b31ea3 193define('PARAM_RAW', 'raw');
bed79931 194
652599ec
TH
195/**
196 * PARAM_RAW_TRIMMED like PARAM_RAW but leading and trailing whitespace is stripped.
197 */
198define('PARAM_RAW_TRIMMED', 'raw_trimmed');
199
bcef0319 200/**
03b31ea3 201 * PARAM_SAFEDIR - safe directory name, suitable for include() and require()
bcef0319 202 */
03b31ea3 203define('PARAM_SAFEDIR', 'safedir');
bcef0319 204
e032888c 205/**
03b31ea3 206 * PARAM_SAFEPATH - several PARAM_SAFEDIR joined by "/", suitable for include() and require(), plugin paths, etc.
38fb8190 207 */
03b31ea3 208define('PARAM_SAFEPATH', 'safepath');
e032888c 209
bbd3f2c4 210/**
03b31ea3 211 * PARAM_SEQUENCE - expects a sequence of numbers like 8 to 1,5,6,4,6,8,9. Numbers and comma only.
bbd3f2c4 212 */
03b31ea3 213define('PARAM_SEQUENCE', 'sequence');
bbd3f2c4 214
215/**
03b31ea3 216 * PARAM_TAG - one tag (interests, blogs, etc.) - mostly international characters and space, <> not supported
bbd3f2c4 217 */
03b31ea3 218define('PARAM_TAG', 'tag');
bbd3f2c4 219
220/**
03b31ea3 221 * PARAM_TAGLIST - list of tags separated by commas (interests, blogs, etc.)
bbd3f2c4 222 */
03b31ea3 223define('PARAM_TAGLIST', 'taglist');
bbd3f2c4 224
225/**
b6059edc 226 * PARAM_TEXT - general plain text compatible with multilang filter, no other html tags. Please note '<', or '>' are allowed here.
bbd3f2c4 227 */
03b31ea3 228define('PARAM_TEXT', 'text');
bbd3f2c4 229
bbd3f2c4 230/**
03b31ea3 231 * PARAM_THEME - Checks to see if the string is a valid theme name in the current site
bbd3f2c4 232 */
03b31ea3 233define('PARAM_THEME', 'theme');
bbd3f2c4 234
235/**
ac7af0da
SH
236 * PARAM_URL - expected properly formatted URL. Please note that domain part is required, http://localhost/ is not accepted but
237 * http://localhost.localdomain/ is ok.
bbd3f2c4 238 */
03b31ea3 239define('PARAM_URL', 'url');
240
07ed083e 241/**
ac7af0da
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242 * PARAM_USERNAME - Clean username to only contains allowed characters. This is to be used ONLY when manually creating user
243 * accounts, do NOT use when syncing with external systems!!
07ed083e
RW
244 */
245define('PARAM_USERNAME', 'username');
bbd3f2c4 246
fe6a248f
DM
247/**
248 * PARAM_STRINGID - used to check if the given string is valid string identifier for get_string()
249 */
250define('PARAM_STRINGID', 'stringid');
03b31ea3 251
ac7af0da 252// DEPRECATED PARAM TYPES OR ALIASES - DO NOT USE FOR NEW CODE.
bbd3f2c4 253/**
03b31ea3 254 * PARAM_CLEAN - obsoleted, please use a more specific type of parameter.
255 * It was one of the first types, that is why it is abused so much ;-)
44913c8d 256 * @deprecated since 2.0
bbd3f2c4 257 */
03b31ea3 258define('PARAM_CLEAN', 'clean');
bbd3f2c4 259
260/**
03b31ea3 261 * PARAM_INTEGER - deprecated alias for PARAM_INT
1e12c120 262 * @deprecated since 2.0
bbd3f2c4 263 */
03b31ea3 264define('PARAM_INTEGER', 'int');
bbd3f2c4 265
0e4af166 266/**
03b31ea3 267 * PARAM_NUMBER - deprecated alias of PARAM_FLOAT
61cca0b7 268 * @deprecated since 2.0
0e4af166 269 */
03b31ea3 270define('PARAM_NUMBER', 'float');
0e4af166 271
03d820c7 272/**
efb8c375 273 * PARAM_ACTION - deprecated alias for PARAM_ALPHANUMEXT, use for various actions in forms and urls
03b31ea3 274 * NOTE: originally alias for PARAM_APLHA
405aca35 275 * @deprecated since 2.0
03d820c7 276 */
03b31ea3 277define('PARAM_ACTION', 'alphanumext');
03d820c7 278
279/**
03b31ea3 280 * PARAM_FORMAT - deprecated alias for PARAM_ALPHANUMEXT, use for names of plugins, formats, etc.
281 * NOTE: originally alias for PARAM_APLHA
405aca35 282 * @deprecated since 2.0
03d820c7 283 */
03b31ea3 284define('PARAM_FORMAT', 'alphanumext');
03d820c7 285
ad944e78 286/**
03b31ea3 287 * PARAM_MULTILANG - deprecated alias of PARAM_TEXT.
071e68f9 288 * @deprecated since 2.0
ad944e78 289 */
03b31ea3 290define('PARAM_MULTILANG', 'text');
03d820c7 291
ccc77f91
RT
292/**
293 * PARAM_TIMEZONE - expected timezone. Timezone can be int +-(0-13) or float +-(0.5-12.5) or
ac7af0da 294 * string separated by '/' and can have '-' &/ '_' (eg. America/North_Dakota/New_Salem
ccc77f91
RT
295 * America/Port-au-Prince)
296 */
297define('PARAM_TIMEZONE', 'timezone');
298
faf75fe7 299/**
03b31ea3 300 * PARAM_CLEANFILE - deprecated alias of PARAM_FILE; originally was removing regional chars too
faf75fe7 301 */
03b31ea3 302define('PARAM_CLEANFILE', 'file');
303
aff24313
PS
304/**
305 * PARAM_COMPONENT is used for full component names (aka frankenstyle) such as 'mod_forum', 'core_rating', 'auth_ldap'.
306 * Short legacy subsystem names and module names are accepted too ex: 'forum', 'rating', 'user'.
307 * Only lowercase ascii letters, numbers and underscores are allowed, it has to start with a letter.
308 * NOTE: numbers and underscores are strongly discouraged in plugin names!
309 */
310define('PARAM_COMPONENT', 'component');
311
312/**
313 * PARAM_AREA is a name of area used when addressing files, comments, ratings, etc.
314 * It is usually used together with context id and component.
315 * Only lowercase ascii letters, numbers and underscores are allowed, it has to start with a letter.
316 */
317define('PARAM_AREA', 'area');
318
319/**
320 * PARAM_PLUGIN is used for plugin names such as 'forum', 'glossary', 'ldap', 'radius', 'paypal', 'completionstatus'.
321 * Only lowercase ascii letters, numbers and underscores are allowed, it has to start with a letter.
322 * NOTE: numbers and underscores are strongly discouraged in plugin names! Underscores are forbidden in module names.
323 */
324define('PARAM_PLUGIN', 'plugin');
325
326
ac7af0da 327// Web Services.
03b31ea3 328
382b9cea 329/**
330 * VALUE_REQUIRED - if the parameter is not supplied, there is an error
331 */
332define('VALUE_REQUIRED', 1);
333
334/**
335 * VALUE_OPTIONAL - if the parameter is not supplied, then the param has no value
336 */
337define('VALUE_OPTIONAL', 2);
338
339/**
340 * VALUE_DEFAULT - if the parameter is not supplied, then the default value is used
341 */
342define('VALUE_DEFAULT', 0);
03b31ea3 343
5a1861ee 344/**
345 * NULL_NOT_ALLOWED - the parameter can not be set to null in the database
346 */
347define('NULL_NOT_ALLOWED', false);
348
349/**
350 * NULL_ALLOWED - the parameter can be set to null in the database
351 */
352define('NULL_ALLOWED', true);
faf75fe7 353
ac7af0da
SH
354// Page types.
355
bbd3f2c4 356/**
357 * PAGE_COURSE_VIEW is a definition of a page type. For more information on the page class see moodle/lib/pagelib.php.
8bd3fad3 358 */
359define('PAGE_COURSE_VIEW', 'course-view');
8bd3fad3 360
9bda43e6 361/** Get remote addr constant */
362define('GETREMOTEADDR_SKIP_HTTP_CLIENT_IP', '1');
363/** Get remote addr constant */
364define('GETREMOTEADDR_SKIP_HTTP_X_FORWARDED_FOR', '2');
6e73ae10 365
ac7af0da 366// Blog access level constant declaration.
feaf5d06 367define ('BLOG_USER_LEVEL', 1);
368define ('BLOG_GROUP_LEVEL', 2);
369define ('BLOG_COURSE_LEVEL', 3);
370define ('BLOG_SITE_LEVEL', 4);
371define ('BLOG_GLOBAL_LEVEL', 5);
372
6e73ae10 373
ac7af0da 374// Tag constants.
4eb718d8 375/**
a905364a 376 * To prevent problems with multibytes strings,Flag updating in nav not working on the review page. this should not exceed the
6e73ae10 377 * length of "varchar(255) / 3 (bytes / utf-8 character) = 85".
378 * TODO: this is not correct, varchar(255) are 255 unicode chars ;-)
0d0a8bf6 379 *
380 * @todo define(TAG_MAX_LENGTH) this is not correct, varchar(255) are 255 unicode chars ;-)
4eb718d8 381 */
ae040d4b 382define('TAG_MAX_LENGTH', 50);
4eb718d8 383
ac7af0da 384// Password policy constants.
6499395e 385define ('PASSWORD_LOWER', 'abcdefghijklmnopqrstuvwxyz');
386define ('PASSWORD_UPPER', 'ABCDEFGHIJKLMNOPQRSTUVWXYZ');
387define ('PASSWORD_DIGITS', '0123456789');
388define ('PASSWORD_NONALPHANUM', '.,;:!?_-+/*@#&$');
389
ac7af0da 390// Feature constants.
6e73ae10 391// Used for plugin_supports() to report features that are, or are not, supported by a module.
49f6e5f4 392
393/** True if module can provide a grade */
61fceb86 394define('FEATURE_GRADE_HAS_GRADE', 'grade_has_grade');
42f103be 395/** True if module supports outcomes */
396define('FEATURE_GRADE_OUTCOMES', 'outcomes');
b11f9da6
DM
397/** True if module supports advanced grading methods */
398define('FEATURE_ADVANCED_GRADING', 'grade_advanced_grading');
455dc0de
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399/** True if module controls the grade visibility over the gradebook */
400define('FEATURE_CONTROLS_GRADE_VISIBILITY', 'controlsgradevisbility');
50da4ddd
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401/** True if module supports plagiarism plugins */
402define('FEATURE_PLAGIARISM', 'plagiarism');
42f103be 403
49f6e5f4 404/** True if module has code to track whether somebody viewed it */
61fceb86 405define('FEATURE_COMPLETION_TRACKS_VIEWS', 'completion_tracks_views');
49f6e5f4 406/** True if module has custom completion rules */
61fceb86 407define('FEATURE_COMPLETION_HAS_RULES', 'completion_has_rules');
49f6e5f4 408
0d8b6a69 409/** True if module has no 'view' page (like label) */
410define('FEATURE_NO_VIEW_LINK', 'viewlink');
42f103be 411/** True if module supports outcomes */
412define('FEATURE_IDNUMBER', 'idnumber');
413/** True if module supports groups */
414define('FEATURE_GROUPS', 'groups');
415/** True if module supports groupings */
416define('FEATURE_GROUPINGS', 'groupings');
417/** True if module supports groupmembersonly */
418define('FEATURE_GROUPMEMBERSONLY', 'groupmembersonly');
419
aa54ed7b 420/** Type of module */
421define('FEATURE_MOD_ARCHETYPE', 'mod_archetype');
42f103be 422/** True if module supports intro editor */
dc5c2bd9 423define('FEATURE_MOD_INTRO', 'mod_intro');
42f103be 424/** True if module has default completion */
425define('FEATURE_MODEDIT_DEFAULT_COMPLETION', 'modedit_default_completion');
49f6e5f4 426
1bcb7eb5 427define('FEATURE_COMMENT', 'comment');
428
6c5fcef7 429define('FEATURE_RATE', 'rate');
4bfdcfcf
EL
430/** True if module supports backup/restore of moodle2 format */
431define('FEATURE_BACKUP_MOODLE2', 'backup_moodle2');
a09aeee4 432
8c40662e 433/** True if module can show description on course main page */
434define('FEATURE_SHOW_DESCRIPTION', 'showdescription');
435
b07ef13b
DP
436/** True if module uses the question bank */
437define('FEATURE_USES_QUESTIONS', 'usesquestions');
438
aa54ed7b 439/** Unspecified module archetype */
440define('MOD_ARCHETYPE_OTHER', 0);
441/** Resource-like type module */
442define('MOD_ARCHETYPE_RESOURCE', 1);
efb8c375 443/** Assignment module archetype */
aa54ed7b 444define('MOD_ARCHETYPE_ASSIGNMENT', 2);
5813c7f7 445/** System (not user-addable) module archetype */
446define('MOD_ARCHETYPE_SYSTEM', 3);
aa54ed7b 447
50ae8814
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448/** Return this from modname_get_types callback to use default display in activity chooser */
449define('MOD_SUBTYPE_NO_CHILDREN', 'modsubtypenochildren');
450
eec99048 451/**
452 * Security token used for allowing access
453 * from external application such as web services.
454 * Scripts do not use any session, performance is relatively
455 * low because we need to load access info in each request.
efb8c375 456 * Scripts are executed in parallel.
eec99048 457 */
458define('EXTERNAL_TOKEN_PERMANENT', 0);
459
460/**
461 * Security token used for allowing access
462 * of embedded applications, the code is executed in the
463 * active user session. Token is invalidated after user logs out.
464 * Scripts are executed serially - normal session locking is used.
465 */
466define('EXTERNAL_TOKEN_EMBEDDED', 1);
49f6e5f4 467
4766a50c
SH
468/**
469 * The home page should be the site home
470 */
471define('HOMEPAGE_SITE', 0);
472/**
473 * The home page should be the users my page
474 */
475define('HOMEPAGE_MY', 1);
476/**
477 * The home page can be chosen by the user
478 */
479define('HOMEPAGE_USER', 2);
fcce139a 480
94788de2 481/**
482 * Hub directory url (should be moodle.org)
483 */
484define('HUB_HUBDIRECTORYURL', "http://hubdirectory.moodle.org");
485
486
487/**
488 * Moodle.org url (should be moodle.org)
489 */
490define('HUB_MOODLEORGHUBURL', "http://hub.moodle.org");
491
c1b65883
JM
492/**
493 * Moodle mobile app service name
494 */
495define('MOODLE_OFFICIAL_MOBILE_SERVICE', 'moodle_mobile_app');
94788de2 496
bc8da017
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497/**
498 * Indicates the user has the capabilities required to ignore activity and course file size restrictions
499 */
500define('USER_CAN_IGNORE_FILE_SIZE_LIMITS', -1);
501
1f09018a 502/**
ac7af0da
SH
503 * Course display settings: display all sections on one page.
504 */
505define('COURSE_DISPLAY_SINGLEPAGE', 0);
506/**
507 * Course display settings: split pages into a page per section.
1f09018a 508 */
ac7af0da 509define('COURSE_DISPLAY_MULTIPAGE', 1);
1f09018a 510
ec2d8ceb 511/**
ac7af0da 512 * Authentication constant: String used in password field when password is not stored.
ec2d8ceb 513 */
ac7af0da 514define('AUTH_PASSWORD_NOT_CACHED', 'not cached');
ec2d8ceb 515
ac7af0da 516// PARAMETER HANDLING.
6b174680 517
e0d346ff 518/**
361855e6 519 * Returns a particular value for the named variable, taken from
520 * POST or GET. If the parameter doesn't exist then an error is
e0d346ff 521 * thrown because we require this variable.
522 *
361855e6 523 * This function should be used to initialise all required values
524 * in a script that are based on parameters. Usually it will be
e0d346ff 525 * used like this:
622365d2 526 * $id = required_param('id', PARAM_INT);
e0d346ff 527 *
2ca3bffa 528 * Please note the $type parameter is now required and the value can not be array.
44913c8d
PS
529 *
530 * @param string $parname the name of the page parameter we want
531 * @param string $type expected type of parameter
e0d346ff 532 * @return mixed
ac7af0da 533 * @throws coding_exception
e0d346ff 534 */
44913c8d 535function required_param($parname, $type) {
2ca3bffa
PS
536 if (func_num_args() != 2 or empty($parname) or empty($type)) {
537 throw new coding_exception('required_param() requires $parname and $type to be specified (parameter: '.$parname.')');
44913c8d 538 }
ac7af0da
SH
539 // POST has precedence.
540 if (isset($_POST[$parname])) {
a083b93c 541 $param = $_POST[$parname];
542 } else if (isset($_GET[$parname])) {
543 $param = $_GET[$parname];
e0d346ff 544 } else {
2f137aa1 545 print_error('missingparam', '', '', $parname);
e0d346ff 546 }
547
2ca3bffa
PS
548 if (is_array($param)) {
549 debugging('Invalid array parameter detected in required_param(): '.$parname);
ac7af0da 550 // TODO: switch to fatal error in Moodle 2.3.
2ca3bffa
PS
551 return required_param_array($parname, $type);
552 }
553
a083b93c 554 return clean_param($param, $type);
e0d346ff 555}
556
2ca3bffa
PS
557/**
558 * Returns a particular array value for the named variable, taken from
559 * POST or GET. If the parameter doesn't exist then an error is
560 * thrown because we require this variable.
561 *
562 * This function should be used to initialise all required values
563 * in a script that are based on parameters. Usually it will be
564 * used like this:
565 * $ids = required_param_array('ids', PARAM_INT);
566 *
567 * Note: arrays of arrays are not supported, only alphanumeric keys with _ and - are supported
568 *
569 * @param string $parname the name of the page parameter we want
570 * @param string $type expected type of parameter
571 * @return array
ac7af0da 572 * @throws coding_exception
2ca3bffa
PS
573 */
574function required_param_array($parname, $type) {
575 if (func_num_args() != 2 or empty($parname) or empty($type)) {
576 throw new coding_exception('required_param_array() requires $parname and $type to be specified (parameter: '.$parname.')');
577 }
ac7af0da
SH
578 // POST has precedence.
579 if (isset($_POST[$parname])) {
2ca3bffa
PS
580 $param = $_POST[$parname];
581 } else if (isset($_GET[$parname])) {
582 $param = $_GET[$parname];
583 } else {
584 print_error('missingparam', '', '', $parname);
585 }
586 if (!is_array($param)) {
587 print_error('missingparam', '', '', $parname);
588 }
589
590 $result = array();
ac7af0da 591 foreach ($param as $key => $value) {
2ca3bffa
PS
592 if (!preg_match('/^[a-z0-9_-]+$/i', $key)) {
593 debugging('Invalid key name in required_param_array() detected: '.$key.', parameter: '.$parname);
594 continue;
595 }
ebdeccca 596 $result[$key] = clean_param($value, $type);
2ca3bffa
PS
597 }
598
599 return $result;
e0d346ff 600}
601
602/**
361855e6 603 * Returns a particular value for the named variable, taken from
e0d346ff 604 * POST or GET, otherwise returning a given default.
605 *
361855e6 606 * This function should be used to initialise all optional values
607 * in a script that are based on parameters. Usually it will be
e0d346ff 608 * used like this:
622365d2 609 * $name = optional_param('name', 'Fred', PARAM_TEXT);
e0d346ff 610 *
2ca3bffa 611 * Please note the $type parameter is now required and the value can not be array.
44913c8d 612 *
a083b93c 613 * @param string $parname the name of the page parameter we want
e0d346ff 614 * @param mixed $default the default value to return if nothing is found
44913c8d 615 * @param string $type expected type of parameter
e0d346ff 616 * @return mixed
ac7af0da 617 * @throws coding_exception
e0d346ff 618 */
44913c8d 619function optional_param($parname, $default, $type) {
2ca3bffa 620 if (func_num_args() != 3 or empty($parname) or empty($type)) {
ac7af0da 621 throw new coding_exception('optional_param requires $parname, $default + $type to be specified (parameter: '.$parname.')');
44913c8d
PS
622 }
623 if (!isset($default)) {
624 $default = null;
625 }
626
ac7af0da
SH
627 // POST has precedence.
628 if (isset($_POST[$parname])) {
a083b93c 629 $param = $_POST[$parname];
630 } else if (isset($_GET[$parname])) {
631 $param = $_GET[$parname];
e0d346ff 632 } else {
633 return $default;
634 }
c7f4e3e2 635
2ca3bffa
PS
636 if (is_array($param)) {
637 debugging('Invalid array parameter detected in required_param(): '.$parname);
ac7af0da 638 // TODO: switch to $default in Moodle 2.3.
2ca3bffa
PS
639 return optional_param_array($parname, $default, $type);
640 }
641
a083b93c 642 return clean_param($param, $type);
e0d346ff 643}
644
2ca3bffa
PS
645/**
646 * Returns a particular array value for the named variable, taken from
647 * POST or GET, otherwise returning a given default.
648 *
649 * This function should be used to initialise all optional values
650 * in a script that are based on parameters. Usually it will be
651 * used like this:
652 * $ids = optional_param('id', array(), PARAM_INT);
653 *
ac7af0da 654 * Note: arrays of arrays are not supported, only alphanumeric keys with _ and - are supported
2ca3bffa
PS
655 *
656 * @param string $parname the name of the page parameter we want
ac7af0da 657 * @param mixed $default the default value to return if nothing is found
2ca3bffa
PS
658 * @param string $type expected type of parameter
659 * @return array
ac7af0da 660 * @throws coding_exception
2ca3bffa
PS
661 */
662function optional_param_array($parname, $default, $type) {
663 if (func_num_args() != 3 or empty($parname) or empty($type)) {
ac7af0da 664 throw new coding_exception('optional_param_array requires $parname, $default + $type to be specified (parameter: '.$parname.')');
2ca3bffa
PS
665 }
666
ac7af0da
SH
667 // POST has precedence.
668 if (isset($_POST[$parname])) {
2ca3bffa
PS
669 $param = $_POST[$parname];
670 } else if (isset($_GET[$parname])) {
671 $param = $_GET[$parname];
672 } else {
673 return $default;
674 }
675 if (!is_array($param)) {
676 debugging('optional_param_array() expects array parameters only: '.$parname);
677 return $default;
678 }
679
680 $result = array();
ac7af0da 681 foreach ($param as $key => $value) {
2ca3bffa
PS
682 if (!preg_match('/^[a-z0-9_-]+$/i', $key)) {
683 debugging('Invalid key name in optional_param_array() detected: '.$key.', parameter: '.$parname);
684 continue;
685 }
ebdeccca 686 $result[$key] = clean_param($value, $type);
2ca3bffa
PS
687 }
688
689 return $result;
e0d346ff 690}
691
a3f7cbf6 692/**
693 * Strict validation of parameter values, the values are only converted
694 * to requested PHP type. Internally it is using clean_param, the values
695 * before and after cleaning must be equal - otherwise
696 * an invalid_parameter_exception is thrown.
efb8c375 697 * Objects and classes are not accepted.
a3f7cbf6 698 *
699 * @param mixed $param
2ca3bffa 700 * @param string $type PARAM_ constant
a3f7cbf6 701 * @param bool $allownull are nulls valid value?
702 * @param string $debuginfo optional debug information
fea52c11
PS
703 * @return mixed the $param value converted to PHP type
704 * @throws invalid_parameter_exception if $param is not of given type
a3f7cbf6 705 */
5a1861ee 706function validate_param($param, $type, $allownull=NULL_NOT_ALLOWED, $debuginfo='') {
a3f7cbf6 707 if (is_null($param)) {
5a1861ee 708 if ($allownull == NULL_ALLOWED) {
a3f7cbf6 709 return null;
710 } else {
711 throw new invalid_parameter_exception($debuginfo);
712 }
713 }
714 if (is_array($param) or is_object($param)) {
715 throw new invalid_parameter_exception($debuginfo);
716 }
717
718 $cleaned = clean_param($param, $type);
fea52c11
PS
719
720 if ($type == PARAM_FLOAT) {
721 // Do not detect precision loss here.
722 if (is_float($param) or is_int($param)) {
723 // These always fit.
724 } else if (!is_numeric($param) or !preg_match('/^[\+-]?[0-9]*\.?[0-9]*(e[-+]?[0-9]+)?$/i', (string)$param)) {
725 throw new invalid_parameter_exception($debuginfo);
726 }
727 } else if ((string)$param !== (string)$cleaned) {
ac7af0da 728 // Conversion to string is usually lossless.
a3f7cbf6 729 throw new invalid_parameter_exception($debuginfo);
730 }
731
732 return $cleaned;
733}
734
2ca3bffa 735/**
ac7af0da
SH
736 * Makes sure array contains only the allowed types, this function does not validate array key names!
737 *
2ca3bffa
PS
738 * <code>
739 * $options = clean_param($options, PARAM_INT);
740 * </code>
741 *
742 * @param array $param the variable array we are cleaning
743 * @param string $type expected format of param after cleaning.
744 * @param bool $recursive clean recursive arrays
745 * @return array
ac7af0da 746 * @throws coding_exception
2ca3bffa
PS
747 */
748function clean_param_array(array $param = null, $type, $recursive = false) {
ac7af0da
SH
749 // Convert null to empty array.
750 $param = (array)$param;
2ca3bffa
PS
751 foreach ($param as $key => $value) {
752 if (is_array($value)) {
753 if ($recursive) {
754 $param[$key] = clean_param_array($value, $type, true);
755 } else {
ac7af0da 756 throw new coding_exception('clean_param_array can not process multidimensional arrays when $recursive is false.');
2ca3bffa
PS
757 }
758 } else {
759 $param[$key] = clean_param($value, $type);
760 }
761 }
762 return $param;
763}
764
e0d346ff 765/**
361855e6 766 * Used by {@link optional_param()} and {@link required_param()} to
767 * clean the variables and/or cast to specific types, based on
e0d346ff 768 * an options field.
bbd3f2c4 769 * <code>
770 * $course->format = clean_param($course->format, PARAM_ALPHA);
ac7af0da 771 * $selectedgradeitem = clean_param($selectedgradeitem, PARAM_INT);
bbd3f2c4 772 * </code>
e0d346ff 773 *
774 * @param mixed $param the variable we are cleaning
2ca3bffa 775 * @param string $type expected format of param after cleaning.
e0d346ff 776 * @return mixed
ac7af0da 777 * @throws coding_exception
e0d346ff 778 */
a083b93c 779function clean_param($param, $type) {
7744ea12 780 global $CFG;
c7f4e3e2 781
c16c1be7
PS
782 if (is_array($param)) {
783 throw new coding_exception('clean_param() can not process arrays, please use clean_param_array() instead.');
784 } else if (is_object($param)) {
785 if (method_exists($param, '__toString')) {
786 $param = $param->__toString();
787 } else {
788 throw new coding_exception('clean_param() can not process objects, please use clean_param_array() instead.');
789 }
80bfd470 790 }
791
a083b93c 792 switch ($type) {
ac7af0da
SH
793 case PARAM_RAW:
794 // No cleaning at all.
78fcdb5f 795 $param = fix_utf8($param);
96e98ea6 796 return $param;
797
ac7af0da
SH
798 case PARAM_RAW_TRIMMED:
799 // No cleaning, but strip leading and trailing whitespace.
78fcdb5f 800 $param = fix_utf8($param);
652599ec
TH
801 return trim($param);
802
ac7af0da
SH
803 case PARAM_CLEAN:
804 // General HTML cleaning, try to use more specific type if possible this is deprecated!
805 // Please use more specific type instead.
a083b93c 806 if (is_numeric($param)) {
807 return $param;
808 }
78fcdb5f 809 $param = fix_utf8($param);
ac7af0da
SH
810 // Sweep for scripts, etc.
811 return clean_text($param);
3af57507 812
ac7af0da
SH
813 case PARAM_CLEANHTML:
814 // Clean html fragment.
78fcdb5f 815 $param = fix_utf8($param);
ac7af0da
SH
816 // Sweep for scripts, etc.
817 $param = clean_text($param, FORMAT_HTML);
a083b93c 818 return trim($param);
e0d346ff 819
a083b93c 820 case PARAM_INT:
ac7af0da
SH
821 // Convert to integer.
822 return (int)$param;
e0d346ff 823
6e73ae10 824 case PARAM_FLOAT:
ac7af0da
SH
825 // Convert to float.
826 return (float)$param;
9dae915a 827
ac7af0da
SH
828 case PARAM_ALPHA:
829 // Remove everything not `a-z`.
6dbcacee 830 return preg_replace('/[^a-zA-Z]/i', '', $param);
e0d346ff 831
ac7af0da
SH
832 case PARAM_ALPHAEXT:
833 // Remove everything not `a-zA-Z_-` (originally allowed "/" too).
6dbcacee 834 return preg_replace('/[^a-zA-Z_-]/i', '', $param);
6e73ae10 835
ac7af0da
SH
836 case PARAM_ALPHANUM:
837 // Remove everything not `a-zA-Z0-9`.
6dbcacee 838 return preg_replace('/[^A-Za-z0-9]/i', '', $param);
f24148ef 839
ac7af0da
SH
840 case PARAM_ALPHANUMEXT:
841 // Remove everything not `a-zA-Z0-9_-`.
6dbcacee 842 return preg_replace('/[^A-Za-z0-9_-]/i', '', $param);
0ed442f8 843
ac7af0da
SH
844 case PARAM_SEQUENCE:
845 // Remove everything not `0-9,`.
6dbcacee 846 return preg_replace('/[^0-9,]/i', '', $param);
0e4af166 847
ac7af0da
SH
848 case PARAM_BOOL:
849 // Convert to 1 or 0.
a083b93c 850 $tempstr = strtolower($param);
6e73ae10 851 if ($tempstr === 'on' or $tempstr === 'yes' or $tempstr === 'true') {
a083b93c 852 $param = 1;
6e73ae10 853 } else if ($tempstr === 'off' or $tempstr === 'no' or $tempstr === 'false') {
a083b93c 854 $param = 0;
855 } else {
856 $param = empty($param) ? 0 : 1;
857 }
858 return $param;
f24148ef 859
ac7af0da
SH
860 case PARAM_NOTAGS:
861 // Strip all tags.
78fcdb5f 862 $param = fix_utf8($param);
a083b93c 863 return strip_tags($param);
3af57507 864
ac7af0da
SH
865 case PARAM_TEXT:
866 // Leave only tags needed for multilang.
78fcdb5f 867 $param = fix_utf8($param);
ac7af0da
SH
868 // If the multilang syntax is not correct we strip all tags because it would break xhtml strict which is required
869 // for accessibility standards please note this cleaning does not strip unbalanced '>' for BC compatibility reasons.
b6059edc
PS
870 do {
871 if (strpos($param, '</lang>') !== false) {
ac7af0da 872 // Old and future mutilang syntax.
b6059edc
PS
873 $param = strip_tags($param, '<lang>');
874 if (!preg_match_all('/<.*>/suU', $param, $matches)) {
875 break;
876 }
877 $open = false;
878 foreach ($matches[0] as $match) {
879 if ($match === '</lang>') {
880 if ($open) {
881 $open = false;
882 continue;
883 } else {
884 break 2;
885 }
886 }
887 if (!preg_match('/^<lang lang="[a-zA-Z0-9_-]+"\s*>$/u', $match)) {
888 break 2;
889 } else {
890 $open = true;
891 }
892 }
893 if ($open) {
894 break;
895 }
896 return $param;
897
898 } else if (strpos($param, '</span>') !== false) {
ac7af0da 899 // Current problematic multilang syntax.
b6059edc
PS
900 $param = strip_tags($param, '<span>');
901 if (!preg_match_all('/<.*>/suU', $param, $matches)) {
902 break;
903 }
904 $open = false;
905 foreach ($matches[0] as $match) {
906 if ($match === '</span>') {
907 if ($open) {
908 $open = false;
909 continue;
910 } else {
911 break 2;
912 }
913 }
914 if (!preg_match('/^<span(\s+lang="[a-zA-Z0-9_-]+"|\s+class="multilang"){2}\s*>$/u', $match)) {
915 break 2;
916 } else {
917 $open = true;
918 }
919 }
920 if ($open) {
921 break;
922 }
923 return $param;
924 }
925 } while (false);
ac7af0da 926 // Easy, just strip all tags, if we ever want to fix orphaned '&' we have to do that in format_string().
b6059edc 927 return strip_tags($param);
31f26796 928
aff24313 929 case PARAM_COMPONENT:
ac7af0da
SH
930 // We do not want any guessing here, either the name is correct or not
931 // please note only normalised component names are accepted.
a41d1ca0 932 if (!preg_match('/^[a-z]+(_[a-z][a-z0-9_]*)?[a-z0-9]+$/', $param)) {
aff24313
PS
933 return '';
934 }
935 if (strpos($param, '__') !== false) {
936 return '';
937 }
938 if (strpos($param, 'mod_') === 0) {
ac7af0da 939 // Module names must not contain underscores because we need to differentiate them from invalid plugin types.
aff24313
PS
940 if (substr_count($param, '_') != 1) {
941 return '';
942 }
943 }
944 return $param;
945
946 case PARAM_PLUGIN:
947 case PARAM_AREA:
ac7af0da 948 // We do not want any guessing here, either the name is correct or not.
5f850735 949 if (!is_valid_plugin_name($param)) {
aff24313
PS
950 return '';
951 }
952 return $param;
953
ac7af0da
SH
954 case PARAM_SAFEDIR:
955 // Remove everything not a-zA-Z0-9_- .
6dbcacee 956 return preg_replace('/[^a-zA-Z0-9_-]/i', '', $param);
95bfd207 957
ac7af0da
SH
958 case PARAM_SAFEPATH:
959 // Remove everything not a-zA-Z0-9/_- .
6759ad2f 960 return preg_replace('/[^a-zA-Z0-9\/_-]/i', '', $param);
6e73ae10 961
ac7af0da
SH
962 case PARAM_FILE:
963 // Strip all suspicious characters from filename.
78fcdb5f 964 $param = fix_utf8($param);
14f3ad15 965 $param = preg_replace('~[[:cntrl:]]|[&<>"`\|\':\\\\/]~u', '', $param);
caf16a57 966 if ($param === '.' || $param === '..') {
371a2ed0 967 $param = '';
968 }
a083b93c 969 return $param;
970
ac7af0da
SH
971 case PARAM_PATH:
972 // Strip all suspicious characters from file path.
78fcdb5f 973 $param = fix_utf8($param);
a083b93c 974 $param = str_replace('\\', '/', $param);
caf16a57
FM
975
976 // Explode the path and clean each element using the PARAM_FILE rules.
977 $breadcrumb = explode('/', $param);
978 foreach ($breadcrumb as $key => $crumb) {
979 if ($crumb === '.' && $key === 0) {
980 // Special condition to allow for relative current path such as ./currentdirfile.txt.
981 } else {
982 $crumb = clean_param($crumb, PARAM_FILE);
983 }
984 $breadcrumb[$key] = $crumb;
985 }
986 $param = implode('/', $breadcrumb);
987
988 // Remove multiple current path (./././) and multiple slashes (///).
6dbcacee 989 $param = preg_replace('~//+~', '/', $param);
caf16a57
FM
990 $param = preg_replace('~/(\./)+~', '/', $param);
991 return $param;
a083b93c 992
ac7af0da
SH
993 case PARAM_HOST:
994 // Allow FQDN or IPv4 dotted quad.
995 $param = preg_replace('/[^\.\d\w-]/', '', $param );
996 // Match ipv4 dotted quad.
997 if (preg_match('/(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/', $param, $match)) {
998 // Confirm values are ok.
a083b93c 999 if ( $match[0] > 255
1000 || $match[1] > 255
1001 || $match[3] > 255
1002 || $match[4] > 255 ) {
ac7af0da 1003 // Hmmm, what kind of dotted quad is this?
a083b93c 1004 $param = '';
1005 }
ac7af0da
SH
1006 } else if ( preg_match('/^[\w\d\.-]+$/', $param) // Dots, hyphens, numbers.
1007 && !preg_match('/^[\.-]/', $param) // No leading dots/hyphens.
1008 && !preg_match('/[\.-]$/', $param) // No trailing dots/hyphens.
a083b93c 1009 ) {
ac7af0da 1010 // All is ok - $param is respected.
a083b93c 1011 } else {
ac7af0da 1012 // All is not ok...
a083b93c 1013 $param='';
1014 }
1015 return $param;
7744ea12 1016
ac7af0da 1017 case PARAM_URL: // Allow safe ftp, http, mailto urls.
78fcdb5f 1018 $param = fix_utf8($param);
a083b93c 1019 include_once($CFG->dirroot . '/lib/validateurlsyntax.php');
5301205a 1020 if (!empty($param) && validateUrlSyntax($param, 's?H?S?F?E?u-P-a?I?p?f?q?r?')) {
ac7af0da 1021 // All is ok, param is respected.
d2a9f7cc 1022 } else {
ac7af0da
SH
1023 // Not really ok.
1024 $param ='';
a083b93c 1025 }
1026 return $param;
1027
ac7af0da
SH
1028 case PARAM_LOCALURL:
1029 // Allow http absolute, root relative and relative URLs within wwwroot.
93684765 1030 $param = clean_param($param, PARAM_URL);
a083b93c 1031 if (!empty($param)) {
1032 if (preg_match(':^/:', $param)) {
ac7af0da
SH
1033 // Root-relative, ok!
1034 } else if (preg_match('/^'.preg_quote($CFG->wwwroot, '/').'/i', $param)) {
1035 // Absolute, and matches our wwwroot.
7744ea12 1036 } else {
ac7af0da 1037 // Relative - let's make sure there are no tricks.
4bea5e85 1038 if (validateUrlSyntax('/' . $param, 's-u-P-a-p-f+q?r?')) {
ac7af0da 1039 // Looks ok.
a083b93c 1040 } else {
1041 $param = '';
1042 }
d2a9f7cc 1043 }
7744ea12 1044 }
a083b93c 1045 return $param;
bcef0319 1046
03d820c7 1047 case PARAM_PEM:
1048 $param = trim($param);
ac7af0da
SH
1049 // PEM formatted strings may contain letters/numbers and the symbols:
1050 // forward slash: /
1051 // plus sign: +
1052 // equal sign: =
1053 // , surrounded by BEGIN and END CERTIFICATE prefix and suffixes.
03d820c7 1054 if (preg_match('/^-----BEGIN CERTIFICATE-----([\s\w\/\+=]+)-----END CERTIFICATE-----$/', trim($param), $matches)) {
1055 list($wholething, $body) = $matches;
1056 unset($wholething, $matches);
1057 $b64 = clean_param($body, PARAM_BASE64);
1058 if (!empty($b64)) {
1059 return "-----BEGIN CERTIFICATE-----\n$b64\n-----END CERTIFICATE-----\n";
1060 } else {
1061 return '';
1062 }
1063 }
1064 return '';
bcef0319 1065
03d820c7 1066 case PARAM_BASE64:
1067 if (!empty($param)) {
1068 // PEM formatted strings may contain letters/numbers and the symbols
ac7af0da
SH
1069 // forward slash: /
1070 // plus sign: +
1071 // equal sign: =.
03d820c7 1072 if (0 >= preg_match('/^([\s\w\/\+=]+)$/', trim($param))) {
1073 return '';
1074 }
1075 $lines = preg_split('/[\s]+/', $param, -1, PREG_SPLIT_NO_EMPTY);
ac7af0da
SH
1076 // Each line of base64 encoded data must be 64 characters in length, except for the last line which may be less
1077 // than (or equal to) 64 characters long.
03d820c7 1078 for ($i=0, $j=count($lines); $i < $j; $i++) {
1079 if ($i + 1 == $j) {
1080 if (64 < strlen($lines[$i])) {
1081 return '';
1082 }
1083 continue;
1084 }
7744ea12 1085
03d820c7 1086 if (64 != strlen($lines[$i])) {
1087 return '';
1088 }
1089 }
ac7af0da 1090 return implode("\n", $lines);
03d820c7 1091 } else {
1092 return '';
1093 }
bcef0319 1094
1095 case PARAM_TAG:
78fcdb5f 1096 $param = fix_utf8($param);
34b93e39
PS
1097 // Please note it is not safe to use the tag name directly anywhere,
1098 // it must be processed with s(), urlencode() before embedding anywhere.
ac7af0da 1099 // Remove some nasties.
6b24e35e 1100 $param = preg_replace('~[[:cntrl:]]|[<>`]~u', '', $param);
ac7af0da 1101 // Convert many whitespace chars into one.
bcef0319 1102 $param = preg_replace('/\s+/', ' ', $param);
2f1e464a 1103 $param = core_text::substr(trim($param), 0, TAG_MAX_LENGTH);
c93c6b3b 1104 return $param;
bcef0319 1105
ae040d4b 1106 case PARAM_TAGLIST:
78fcdb5f 1107 $param = fix_utf8($param);
ae040d4b 1108 $tags = explode(',', $param);
1109 $result = array();
1110 foreach ($tags as $tag) {
1111 $res = clean_param($tag, PARAM_TAG);
6e73ae10 1112 if ($res !== '') {
ae040d4b 1113 $result[] = $res;
1114 }
1115 }
1116 if ($result) {
1117 return implode(',', $result);
1118 } else {
1119 return '';
0d626493 1120 }
1121
ad944e78 1122 case PARAM_CAPABILITY:
4f0c2d00 1123 if (get_capability_info($param)) {
ad944e78 1124 return $param;
1125 } else {
1126 return '';
1127 }
1128
faf75fe7 1129 case PARAM_PERMISSION:
1130 $param = (int)$param;
1131 if (in_array($param, array(CAP_INHERIT, CAP_ALLOW, CAP_PREVENT, CAP_PROHIBIT))) {
1132 return $param;
1133 } else {
1134 return CAP_INHERIT;
1135 }
1136
03b31ea3 1137 case PARAM_AUTH:
aff24313
PS
1138 $param = clean_param($param, PARAM_PLUGIN);
1139 if (empty($param)) {
1140 return '';
1141 } else if (exists_auth_plugin($param)) {
03b31ea3 1142 return $param;
1143 } else {
1144 return '';
1145 }
1146
1147 case PARAM_LANG:
1148 $param = clean_param($param, PARAM_SAFEDIR);
ef686eb5 1149 if (get_string_manager()->translation_exists($param)) {
03b31ea3 1150 return $param;
1151 } else {
ac7af0da
SH
1152 // Specified language is not installed or param malformed.
1153 return '';
03b31ea3 1154 }
1155
1156 case PARAM_THEME:
aff24313
PS
1157 $param = clean_param($param, PARAM_PLUGIN);
1158 if (empty($param)) {
1159 return '';
1160 } else if (file_exists("$CFG->dirroot/theme/$param/config.php")) {
73e504bc
PS
1161 return $param;
1162 } else if (!empty($CFG->themedir) and file_exists("$CFG->themedir/$param/config.php")) {
03b31ea3 1163 return $param;
1164 } else {
ac7af0da
SH
1165 // Specified theme is not installed.
1166 return '';
03b31ea3 1167 }
1168
07ed083e 1169 case PARAM_USERNAME:
78fcdb5f 1170 $param = fix_utf8($param);
07ed083e 1171 $param = str_replace(" " , "", $param);
ac7af0da 1172 // Convert uppercase to lowercase MDL-16919.
2f1e464a 1173 $param = core_text::strtolower($param);
34d2b19a 1174 if (empty($CFG->extendedusernamechars)) {
ac7af0da 1175 // Regular expression, eliminate all chars EXCEPT:
07ed083e
RW
1176 // alphanum, dash (-), underscore (_), at sign (@) and period (.) characters.
1177 $param = preg_replace('/[^-\.@_a-z0-9]/', '', $param);
4f0c2d00 1178 }
07ed083e
RW
1179 return $param;
1180
79f1d953 1181 case PARAM_EMAIL:
78fcdb5f 1182 $param = fix_utf8($param);
79f1d953 1183 if (validate_email($param)) {
1184 return $param;
1185 } else {
1186 return '';
1187 }
1188
fe6a248f
DM
1189 case PARAM_STRINGID:
1190 if (preg_match('|^[a-zA-Z][a-zA-Z0-9\.:/_-]*$|', $param)) {
1191 return $param;
1192 } else {
1193 return '';
1194 }
1195
ac7af0da
SH
1196 case PARAM_TIMEZONE:
1197 // Can be int, float(with .5 or .0) or string seperated by '/' and can have '-_'.
78fcdb5f 1198 $param = fix_utf8($param);
8158ce79 1199 $timezonepattern = '/^(([+-]?(0?[0-9](\.[5|0])?|1[0-3](\.0)?|1[0-2]\.5))|(99)|[[:alnum:]]+(\/?[[:alpha:]_-])+)$/';
ccc77f91
RT
1200 if (preg_match($timezonepattern, $param)) {
1201 return $param;
1202 } else {
1203 return '';
1204 }
1205
ac7af0da
SH
1206 default:
1207 // Doh! throw error, switched parameters in optional_param or another serious problem.
03b31ea3 1208 print_error("unknownparamtype", '', '', $type);
2ae28153 1209 }
e0d346ff 1210}
1211
78fcdb5f
PS
1212/**
1213 * Makes sure the data is using valid utf8, invalid characters are discarded.
1214 *
1215 * Note: this function is not intended for full objects with methods and private properties.
1216 *
1217 * @param mixed $value
1218 * @return mixed with proper utf-8 encoding
1219 */
1220function fix_utf8($value) {
1221 if (is_null($value) or $value === '') {
1222 return $value;
1223
1224 } else if (is_string($value)) {
1225 if ((string)(int)$value === $value) {
ac7af0da 1226 // Shortcut.
78fcdb5f
PS
1227 return $value;
1228 }
bff1d60c
PS
1229 // No null bytes expected in our data, so let's remove it.
1230 $value = str_replace("\0", '', $value);
0aff15c2 1231
0aff15c2
PS
1232 // Note: this duplicates min_fix_utf8() intentionally.
1233 static $buggyiconv = null;
1234 if ($buggyiconv === null) {
dd47f210 1235 $buggyiconv = (!function_exists('iconv') or @iconv('UTF-8', 'UTF-8//IGNORE', '100'.chr(130).'€') !== '100€');
0aff15c2
PS
1236 }
1237
1238 if ($buggyiconv) {
1239 if (function_exists('mb_convert_encoding')) {
1240 $subst = mb_substitute_character();
1241 mb_substitute_character('');
1242 $result = mb_convert_encoding($value, 'utf-8', 'utf-8');
1243 mb_substitute_character($subst);
1244
1245 } else {
1246 // Warn admins on admin/index.php page.
1247 $result = $value;
1248 }
1249
1250 } else {
dd47f210 1251 $result = @iconv('UTF-8', 'UTF-8//IGNORE', $value);
51b7297b 1252 }
0aff15c2 1253
51b7297b 1254 return $result;
78fcdb5f
PS
1255
1256 } else if (is_array($value)) {
ac7af0da 1257 foreach ($value as $k => $v) {
78fcdb5f
PS
1258 $value[$k] = fix_utf8($v);
1259 }
1260 return $value;
1261
1262 } else if (is_object($value)) {
ac7af0da
SH
1263 // Do not modify original.
1264 $value = clone($value);
1265 foreach ($value as $k => $v) {
78fcdb5f
PS
1266 $value->$k = fix_utf8($v);
1267 }
1268 return $value;
1269
1270 } else {
ac7af0da 1271 // This is some other type, no utf-8 here.
78fcdb5f
PS
1272 return $value;
1273 }
1274}
1275
6e73ae10 1276/**
1277 * Return true if given value is integer or string with integer value
0d0a8bf6 1278 *
1279 * @param mixed $value String or Int
1280 * @return bool true if number, false if not
6e73ae10 1281 */
1282function is_number($value) {
1283 if (is_int($value)) {
1284 return true;
1285 } else if (is_string($value)) {
1286 return ((string)(int)$value) === $value;
1287 } else {
1288 return false;
1289 }
1290}
7a530277 1291
aa282b10 1292/**
ac7af0da
SH
1293 * Returns host part from url.
1294 *
aa282b10 1295 * @param string $url full url
1296 * @return string host, null if not found
1297 */
1298function get_host_from_url($url) {
1299 preg_match('|^[a-z]+://([a-zA-Z0-9-.]+)|i', $url, $matches);
1300 if ($matches) {
1301 return $matches[1];
1302 }
1303 return null;
1304}
1305
94a6d656 1306/**
0d0a8bf6 1307 * Tests whether anything was returned by text editor
1308 *
94a6d656 1309 * This function is useful for testing whether something you got back from
1310 * the HTML editor actually contains anything. Sometimes the HTML editor
1311 * appear to be empty, but actually you get back a <br> tag or something.
1312 *
1313 * @param string $string a string containing HTML.
1314 * @return boolean does the string contain any actual content - that is text,
efb8c375 1315 * images, objects, etc.
94a6d656 1316 */
1317function html_is_blank($string) {
1318 return trim(strip_tags($string, '<img><object><applet><input><select><textarea><hr>')) == '';
1319}
1320
7cf1c7bd 1321/**
1322 * Set a key in global configuration
1323 *
89dcb99d 1324 * Set a key/value pair in both this session's {@link $CFG} global variable
7cf1c7bd 1325 * and in the 'config' database table for future sessions.
e1ecf0a0 1326 *
1327 * Can also be used to update keys for plugin-scoped configs in config_plugin table.
1328 * In that case it doesn't affect $CFG.
7cf1c7bd 1329 *
6fd511eb 1330 * A NULL value will delete the entry.
1331 *
08b51dd0
JO
1332 * NOTE: this function is called from lib/db/upgrade.php
1333 *
7cf1c7bd 1334 * @param string $name the key to set
9cdb766d 1335 * @param string $value the value to set (without magic quotes)
ac7af0da 1336 * @param string $plugin (optional) the plugin scope, default null
5e2f308b 1337 * @return bool true or exception
7cf1c7bd 1338 */
ac7af0da 1339function set_config($name, $value, $plugin=null) {
ae040d4b 1340 global $CFG, $DB;
42282810 1341
a4080313 1342 if (empty($plugin)) {
220a90c5 1343 if (!array_key_exists($name, $CFG->config_php_settings)) {
ac7af0da 1344 // So it's defined for this invocation at least.
220a90c5 1345 if (is_null($value)) {
1346 unset($CFG->$name);
1347 } else {
ac7af0da
SH
1348 // Settings from db are always strings.
1349 $CFG->$name = (string)$value;
220a90c5 1350 }
1351 }
e1ecf0a0 1352
ac7af0da 1353 if ($DB->get_field('config', 'name', array('name' => $name))) {
5e2f308b 1354 if ($value === null) {
ac7af0da 1355 $DB->delete_records('config', array('name' => $name));
6fd511eb 1356 } else {
ac7af0da 1357 $DB->set_field('config', 'value', $value, array('name' => $name));
6fd511eb 1358 }
a4080313 1359 } else {
5e2f308b 1360 if ($value !== null) {
365a5941 1361 $config = new stdClass();
5e2f308b 1362 $config->name = $name;
1363 $config->value = $value;
1364 $DB->insert_record('config', $config, false);
6fd511eb 1365 }
a4080313 1366 }
e0d9b7c0
SH
1367 if ($name === 'siteidentifier') {
1368 cache_helper::update_site_identifier($value);
1369 }
007bfe8b 1370 cache_helper::invalidate_by_definition('core', 'config', array(), 'core');
ac7af0da
SH
1371 } else {
1372 // Plugin scope.
1373 if ($id = $DB->get_field('config_plugins', 'id', array('name' => $name, 'plugin' => $plugin))) {
6fd511eb 1374 if ($value===null) {
ac7af0da 1375 $DB->delete_records('config_plugins', array('name' => $name, 'plugin' => $plugin));
6fd511eb 1376 } else {
ac7af0da 1377 $DB->set_field('config_plugins', 'value', $value, array('id' => $id));
6fd511eb 1378 }
a4080313 1379 } else {
5e2f308b 1380 if ($value !== null) {
365a5941 1381 $config = new stdClass();
5e2f308b 1382 $config->plugin = $plugin;
1383 $config->name = $name;
1384 $config->value = $value;
1385 $DB->insert_record('config_plugins', $config, false);
6fd511eb 1386 }
a4080313 1387 }
007bfe8b 1388 cache_helper::invalidate_by_definition('core', 'config', array(), $plugin);
a4080313 1389 }
5e2f308b 1390
1391 return true;
a4080313 1392}
1393
1394/**
e1ecf0a0 1395 * Get configuration values from the global config table
a4080313 1396 * or the config_plugins table.
1397 *
13daf6a2 1398 * If called with one parameter, it will load all the config
12bb0c3e 1399 * variables for one plugin, and return them as an object.
13daf6a2 1400 *
12bb0c3e
PS
1401 * If called with 2 parameters it will return a string single
1402 * value or false if the value is not found.
9220fba5 1403 *
08b51dd0
JO
1404 * NOTE: this function is called from lib/db/upgrade.php
1405 *
ac7af0da 1406 * @static string|false $siteidentifier The site identifier is not cached. We use this static cache so
e0d9b7c0 1407 * that we need only fetch it once per request.
12bb0c3e 1408 * @param string $plugin full component name
ac7af0da 1409 * @param string $name default null
07ab0c80 1410 * @return mixed hash-like object or single value, return false no config found
ac7af0da 1411 * @throws dml_exception
a4080313 1412 */
ac7af0da 1413function get_config($plugin, $name = null) {
ae040d4b 1414 global $CFG, $DB;
dfc9ba9b 1415
e0d9b7c0
SH
1416 static $siteidentifier = null;
1417
007bfe8b
SH
1418 if ($plugin === 'moodle' || $plugin === 'core' || empty($plugin)) {
1419 $forced =& $CFG->config_php_settings;
1420 $iscore = true;
1421 $plugin = 'core';
1422 } else {
1423 if (array_key_exists($plugin, $CFG->forced_plugin_settings)) {
1424 $forced =& $CFG->forced_plugin_settings[$plugin];
1425 } else {
1426 $forced = array();
1427 }
1428 $iscore = false;
12bb0c3e
PS
1429 }
1430
e0d9b7c0
SH
1431 if ($siteidentifier === null) {
1432 try {
1433 // This may fail during installation.
1434 // If you have a look at {@link initialise_cfg()} you will see that this is how we detect the need to
1435 // install the database.
1436 $siteidentifier = $DB->get_field('config', 'value', array('name' => 'siteidentifier'));
1437 } catch (dml_exception $ex) {
e0d9b7c0
SH
1438 // Set siteidentifier to false. We don't want to trip this continually.
1439 $siteidentifier = false;
1440 throw $ex;
1441 }
1442 }
1443
1444 if (!empty($name)) {
1445 if (array_key_exists($name, $forced)) {
1446 return (string)$forced[$name];
1447 } else if ($name === 'siteidentifier' && $plugin == 'core') {
1448 return $siteidentifier;
1449 }
007bfe8b
SH
1450 }
1451
1452 $cache = cache::make('core', 'config');
1453 $result = $cache->get($plugin);
d0749719 1454 if ($result === false) {
ac7af0da 1455 // The user is after a recordset.
007bfe8b 1456 if (!$iscore) {
ac7af0da 1457 $result = $DB->get_records_menu('config_plugins', array('plugin' => $plugin), '', 'name,value');
a4080313 1458 } else {
ac7af0da 1459 // This part is not really used any more, but anyway...
007bfe8b 1460 $result = $DB->get_records_menu('config', array(), '', 'name,value');;
a4080313 1461 }
007bfe8b 1462 $cache->set($plugin, $result);
a4080313 1463 }
1464
007bfe8b
SH
1465 if (!empty($name)) {
1466 if (array_key_exists($name, $result)) {
1467 return $result[$name];
bfb82da3 1468 }
007bfe8b
SH
1469 return false;
1470 }
e1ecf0a0 1471
e0d9b7c0
SH
1472 if ($plugin === 'core') {
1473 $result['siteidentifier'] = $siteidentifier;
1474 }
1475
007bfe8b
SH
1476 foreach ($forced as $key => $value) {
1477 if (is_null($value) or is_array($value) or is_object($value)) {
ac7af0da 1478 // We do not want any extra mess here, just real settings that could be saved in db.
007bfe8b
SH
1479 unset($result[$key]);
1480 } else {
ac7af0da 1481 // Convert to string as if it went through the DB.
007bfe8b 1482 $result[$key] = (string)$value;
12bb0c3e 1483 }
39917a09 1484 }
007bfe8b
SH
1485
1486 return (object)$result;
39917a09 1487}
1488
b0270f84 1489/**
ac7af0da 1490 * Removes a key from global configuration.
b0270f84 1491 *
08b51dd0
JO
1492 * NOTE: this function is called from lib/db/upgrade.php
1493 *
b0270f84 1494 * @param string $name the key to set
1495 * @param string $plugin (optional) the plugin scope
4b600aa0 1496 * @return boolean whether the operation succeeded.
b0270f84 1497 */
ac7af0da 1498function unset_config($name, $plugin=null) {
ae040d4b 1499 global $CFG, $DB;
b0270f84 1500
b0270f84 1501 if (empty($plugin)) {
4b600aa0 1502 unset($CFG->$name);
ac7af0da 1503 $DB->delete_records('config', array('name' => $name));
007bfe8b 1504 cache_helper::invalidate_by_definition('core', 'config', array(), 'core');
5e623a33 1505 } else {
ac7af0da 1506 $DB->delete_records('config_plugins', array('name' => $name, 'plugin' => $plugin));
007bfe8b 1507 cache_helper::invalidate_by_definition('core', 'config', array(), $plugin);
b0270f84 1508 }
013376de 1509
1510 return true;
b0270f84 1511}
1512
4b600aa0 1513/**
1514 * Remove all the config variables for a given plugin.
ac7af0da 1515 *
c2ca2d8e 1516 * NOTE: this function is called from lib/db/upgrade.php
4b600aa0 1517 *
1518 * @param string $plugin a plugin, for example 'quiz' or 'qtype_multichoice';
1519 * @return boolean whether the operation succeeded.
1520 */
1521function unset_all_config_for_plugin($plugin) {
1522 global $DB;
ac7af0da 1523 // Delete from the obvious config_plugins first.
013376de 1524 $DB->delete_records('config_plugins', array('plugin' => $plugin));
ac7af0da 1525 // Next delete any suspect settings from config.
a4193166
PS
1526 $like = $DB->sql_like('name', '?', true, true, false, '|');
1527 $params = array($DB->sql_like_escape($plugin.'_', '|') . '%');
1528 $DB->delete_records_select('config', $like, $params);
007bfe8b
SH
1529 // Finally clear both the plugin cache and the core cache (suspect settings now removed from core).
1530 cache_helper::invalidate_by_definition('core', 'config', array(), array('core', $plugin));
1531
013376de 1532 return true;
4b600aa0 1533}
1534
4413941f 1535/**
efb8c375 1536 * Use this function to get a list of users from a config setting of type admin_setting_users_with_capability.
adf176d7
PS
1537 *
1538 * All users are verified if they still have the necessary capability.
1539 *
b3d960e6 1540 * @param string $value the value of the config setting.
4413941f 1541 * @param string $capability the capability - must match the one passed to the admin_setting_users_with_capability constructor.
ac7af0da 1542 * @param bool $includeadmins include administrators.
4413941f 1543 * @return array of user objects.
1544 */
adf176d7 1545function get_users_from_config($value, $capability, $includeadmins = true) {
adf176d7
PS
1546 if (empty($value) or $value === '$@NONE@$') {
1547 return array();
4413941f 1548 }
adf176d7 1549
ac7af0da 1550 // We have to make sure that users still have the necessary capability,
adf176d7 1551 // it should be faster to fetch them all first and then test if they are present
ac7af0da 1552 // instead of validating them one-by-one.
b0c6dc1c 1553 $users = get_users_by_capability(context_system::instance(), $capability);
adf176d7
PS
1554 if ($includeadmins) {
1555 $admins = get_admins();
1556 foreach ($admins as $admin) {
1557 $users[$admin->id] = $admin;
1558 }
1559 }
1560
1561 if ($value === '$@ALL@$') {
1562 return $users;
1563 }
1564
ac7af0da 1565 $result = array(); // Result in correct order.
adf176d7
PS
1566 $allowed = explode(',', $value);
1567 foreach ($allowed as $uid) {
1568 if (isset($users[$uid])) {
1569 $user = $users[$uid];
1570 $result[$user->id] = $user;
1571 }
1572 }
1573
1574 return $result;
4413941f 1575}
1576
f87eab7e
PS
1577
1578/**
ac7af0da 1579 * Invalidates browser caches and cached data in temp.
52642d0d
SH
1580 *
1581 * IMPORTANT - If you are adding anything here to do with the cache directory you should also have a look at
ac7af0da 1582 * {@link phpunit_util::reset_dataroot()}
52642d0d 1583 *
f87eab7e
PS
1584 * @return void
1585 */
1586function purge_all_caches() {
d79d5ac2 1587 global $CFG, $DB;
f87eab7e 1588
f87eab7e
PS
1589 reset_text_filters_cache();
1590 js_reset_all_caches();
1591 theme_reset_all_caches();
1592 get_string_manager()->reset_caches();
2f1e464a 1593 core_text::reset_caches();
e87214bd
PS
1594 if (class_exists('core_plugin_manager')) {
1595 core_plugin_manager::reset_caches();
bde002b8 1596 }
f87eab7e 1597
299cfee5
MG
1598 // Bump up cacherev field for all courses.
1599 try {
1600 increment_revision_number('course', 'cacherev', '');
1601 } catch (moodle_exception $e) {
1602 // Ignore exception since this function is also called before upgrade script when field course.cacherev does not exist yet.
1603 }
1604
d79d5ac2 1605 $DB->reset_caches();
d6a1f63b
SH
1606 cache_helper::purge_all();
1607
ac7af0da 1608 // Purge all other caches: rss, simplepie, etc.
365bec4c 1609 remove_dir($CFG->cachedir.'', true);
f87eab7e 1610
ac7af0da 1611 // Make sure cache dir is writable, throws exception if not.
5a87c912 1612 make_cache_directory('');
f87eab7e 1613
85b38061
PS
1614 // This is the only place where we purge local caches, we are only adding files there.
1615 // The $CFG->localcachedirpurged flag forces local directories to be purged on cluster nodes.
1616 remove_dir($CFG->localcachedir, true);
1617 set_config('localcachedirpurged', time());
1618 make_localcache_directory('', true);
309ae892 1619 \core\task\manager::clear_static_caches();
f87eab7e
PS
1620}
1621
bafd7e78 1622/**
1623 * Get volatile flags
1624 *
1625 * @param string $type
ac7af0da
SH
1626 * @param int $changedsince default null
1627 * @return array records array
bafd7e78 1628 */
ac7af0da 1629function get_cache_flags($type, $changedsince = null) {
ae040d4b 1630 global $DB;
bafd7e78 1631
ac7af0da 1632 $params = array('type' => $type, 'expiry' => time());
ae040d4b 1633 $sqlwhere = "flagtype = :type AND expiry >= :expiry";
ac7af0da 1634 if ($changedsince !== null) {
ae040d4b 1635 $params['changedsince'] = $changedsince;
1636 $sqlwhere .= " AND timemodified > :changedsince";
bafd7e78 1637 }
1638 $cf = array();
ae040d4b 1639 if ($flags = $DB->get_records_select('cache_flags', $sqlwhere, $params, '', 'name,value')) {
bafd7e78 1640 foreach ($flags as $flag) {
1641 $cf[$flag->name] = $flag->value;
1642 }
1643 }
1644 return $cf;
1645}
1646
a489cf72 1647/**
1648 * Get volatile flags
1649 *
1650 * @param string $type
1651 * @param string $name
ac7af0da
SH
1652 * @param int $changedsince default null
1653 * @return string|false The cache flag value or false
a489cf72 1654 */
ac7af0da 1655function get_cache_flag($type, $name, $changedsince=null) {
ae040d4b 1656 global $DB;
a489cf72 1657
ac7af0da 1658 $params = array('type' => $type, 'name' => $name, 'expiry' => time());
a489cf72 1659
ae040d4b 1660 $sqlwhere = "flagtype = :type AND name = :name AND expiry >= :expiry";
ac7af0da 1661 if ($changedsince !== null) {
ae040d4b 1662 $params['changedsince'] = $changedsince;
1663 $sqlwhere .= " AND timemodified > :changedsince";
a489cf72 1664 }
ae040d4b 1665
1666 return $DB->get_field_select('cache_flags', 'value', $sqlwhere, $params);
a489cf72 1667}
bafd7e78 1668
1669/**
1670 * Set a volatile flag
1671 *
1672 * @param string $type the "type" namespace for the key
1673 * @param string $name the key to set
ac7af0da 1674 * @param string $value the value to set (without magic quotes) - null will remove the flag
bafd7e78 1675 * @param int $expiry (optional) epoch indicating expiry - defaults to now()+ 24hs
0d0a8bf6 1676 * @return bool Always returns true
bafd7e78 1677 */
ac7af0da 1678function set_cache_flag($type, $name, $value, $expiry = null) {
ae040d4b 1679 global $DB;
bafd7e78 1680
1681 $timemodified = time();
ac7af0da 1682 if ($expiry === null || $expiry < $timemodified) {
bafd7e78 1683 $expiry = $timemodified + 24 * 60 * 60;
1684 } else {
1685 $expiry = (int)$expiry;
1686 }
1687
ac7af0da
SH
1688 if ($value === null) {
1689 unset_cache_flag($type, $name);
013376de 1690 return true;
bafd7e78 1691 }
1692
ac7af0da
SH
1693 if ($f = $DB->get_record('cache_flags', array('name' => $name, 'flagtype' => $type), '*', IGNORE_MULTIPLE)) {
1694 // This is a potential problem in DEBUG_DEVELOPER.
128f0984 1695 if ($f->value == $value and $f->expiry == $expiry and $f->timemodified == $timemodified) {
ac7af0da 1696 return true; // No need to update.
128f0984 1697 }
ae040d4b 1698 $f->value = $value;
bafd7e78 1699 $f->expiry = $expiry;
1700 $f->timemodified = $timemodified;
013376de 1701 $DB->update_record('cache_flags', $f);
bafd7e78 1702 } else {
365a5941 1703 $f = new stdClass();
bafd7e78 1704 $f->flagtype = $type;
1705 $f->name = $name;
ae040d4b 1706 $f->value = $value;
bafd7e78 1707 $f->expiry = $expiry;
1708 $f->timemodified = $timemodified;
013376de 1709 $DB->insert_record('cache_flags', $f);
bafd7e78 1710 }
013376de 1711 return true;
bafd7e78 1712}
1713
1714/**
1715 * Removes a single volatile flag
1716 *
1717 * @param string $type the "type" namespace for the key
1718 * @param string $name the key to set
bafd7e78 1719 * @return bool
1720 */
1721function unset_cache_flag($type, $name) {
ae040d4b 1722 global $DB;
ac7af0da 1723 $DB->delete_records('cache_flags', array('name' => $name, 'flagtype' => $type));
013376de 1724 return true;
bafd7e78 1725}
1726
1727/**
1728 * Garbage-collect volatile flags
1729 *
0d0a8bf6 1730 * @return bool Always returns true
bafd7e78 1731 */
1732function gc_cache_flags() {
ae040d4b 1733 global $DB;
013376de 1734 $DB->delete_records_select('cache_flags', 'expiry < ?', array(time()));
1735 return true;
bafd7e78 1736}
a4080313 1737
ac7af0da 1738// USER PREFERENCE API.
2660377f 1739
7cf1c7bd 1740/**
39461de3
PS
1741 * Refresh user preference cache. This is used most often for $USER
1742 * object that is stored in session, but it also helps with performance in cron script.
0d0a8bf6 1743 *
39461de3
PS
1744 * Preferences for each user are loaded on first use on every page, then again after the timeout expires.
1745 *
4d6b40a0
GGC
1746 * @package core
1747 * @category preference
1748 * @access public
1749 * @param stdClass $user User object. Preferences are preloaded into 'preference' property
1750 * @param int $cachelifetime Cache life time on the current page (in seconds)
1751 * @throws coding_exception
1752 * @return null
7cf1c7bd 1753 */
39461de3
PS
1754function check_user_preferences_loaded(stdClass $user, $cachelifetime = 120) {
1755 global $DB;
ac7af0da
SH
1756 // Static cache, we need to check on each page load, not only every 2 minutes.
1757 static $loadedusers = array();
2660377f 1758
39461de3
PS
1759 if (!isset($user->id)) {
1760 throw new coding_exception('Invalid $user parameter in check_user_preferences_loaded() call, missing id field');
1761 }
2660377f 1762
39461de3 1763 if (empty($user->id) or isguestuser($user->id)) {
ac7af0da 1764 // No permanent storage for not-logged-in users and guest.
39461de3
PS
1765 if (!isset($user->preference)) {
1766 $user->preference = array();
2660377f 1767 }
39461de3 1768 return;
2660377f 1769 }
70812e39 1770
39461de3 1771 $timenow = time();
070e2616 1772
39461de3
PS
1773 if (isset($loadedusers[$user->id]) and isset($user->preference) and isset($user->preference['_lastloaded'])) {
1774 // Already loaded at least once on this page. Are we up to date?
1775 if ($user->preference['_lastloaded'] + $cachelifetime > $timenow) {
ac7af0da 1776 // No need to reload - we are on the same page and we loaded prefs just a moment ago.
39461de3 1777 return;
70812e39 1778
39461de3 1779 } else if (!get_cache_flag('userpreferenceschanged', $user->id, $user->preference['_lastloaded'])) {
ac7af0da 1780 // No change since the lastcheck on this page.
39461de3
PS
1781 $user->preference['_lastloaded'] = $timenow;
1782 return;
70812e39 1783 }
c6d15803 1784 }
346c3e2f 1785
ac7af0da 1786 // OK, so we have to reload all preferences.
39461de3 1787 $loadedusers[$user->id] = true;
ac7af0da 1788 $user->preference = $DB->get_records_menu('user_preferences', array('userid' => $user->id), '', 'name,value'); // All values.
39461de3 1789 $user->preference['_lastloaded'] = $timenow;
2660377f 1790}
1791
1792/**
ac7af0da 1793 * Called from set/unset_user_preferences, so that the prefs can be correctly reloaded in different sessions.
39461de3
PS
1794 *
1795 * NOTE: internal function, do not call from other code.
0d0a8bf6 1796 *
4d6b40a0 1797 * @package core
ac7af0da
SH
1798 * @access private
1799 * @param integer $userid the user whose prefs were changed.
2660377f 1800 */
1801function mark_user_preferences_changed($userid) {
39461de3
PS
1802 global $CFG;
1803
1804 if (empty($userid) or isguestuser($userid)) {
ac7af0da 1805 // No cache flags for guest and not-logged-in users.
39461de3 1806 return;
2660377f 1807 }
39461de3 1808
2660377f 1809 set_cache_flag('userpreferenceschanged', $userid, 1, time() + $CFG->sessiontimeout);
70812e39 1810}
1811
7cf1c7bd 1812/**
39461de3 1813 * Sets a preference for the specified user.
0d0a8bf6 1814 *
4d6b40a0 1815 * If a $user object is submitted it's 'preference' property is used for the preferences cache.
0d0a8bf6 1816 *
4d6b40a0
GGC
1817 * @package core
1818 * @category preference
1819 * @access public
1820 * @param string $name The key to set as preference for the specified user
1821 * @param string $value The value to set for the $name key in the specified user's
1822 * record, null means delete current value.
1823 * @param stdClass|int|null $user A moodle user object or id, null means current user
1824 * @throws coding_exception
1825 * @return bool Always true or exception
7cf1c7bd 1826 */
39461de3 1827function set_user_preference($name, $value, $user = null) {
ae040d4b 1828 global $USER, $DB;
70812e39 1829
39461de3
PS
1830 if (empty($name) or is_numeric($name) or $name === '_lastloaded') {
1831 throw new coding_exception('Invalid preference name in set_user_preference() call');
70812e39 1832 }
1833
39461de3 1834 if (is_null($value)) {
ac7af0da 1835 // Null means delete current.
39461de3
PS
1836 return unset_user_preference($name, $user);
1837 } else if (is_object($value)) {
1838 throw new coding_exception('Invalid value in set_user_preference() call, objects are not allowed');
1839 } else if (is_array($value)) {
1840 throw new coding_exception('Invalid value in set_user_preference() call, arrays are not allowed');
1841 }
ac7af0da 1842 // Value column maximum length is 1333 characters.
39461de3 1843 $value = (string)$value;
2f1e464a 1844 if (core_text::strlen($value) > 1333) {
8e54ce97
AD
1845 throw new coding_exception('Invalid value in set_user_preference() call, value is is too long for the value column');
1846 }
39461de3
PS
1847
1848 if (is_null($user)) {
1849 $user = $USER;
1850 } else if (isset($user->id)) {
ac7af0da 1851 // It is a valid object.
39461de3 1852 } else if (is_numeric($user)) {
ac7af0da 1853 $user = (object)array('id' => (int)$user);
346c3e2f 1854 } else {
39461de3 1855 throw new coding_exception('Invalid $user parameter in set_user_preference() call');
346c3e2f 1856 }
1857
39461de3
PS
1858 check_user_preferences_loaded($user);
1859
1860 if (empty($user->id) or isguestuser($user->id)) {
ac7af0da 1861 // No permanent storage for not-logged-in users and guest.
39461de3
PS
1862 $user->preference[$name] = $value;
1863 return true;
1864 }
346c3e2f 1865
ac7af0da 1866 if ($preference = $DB->get_record('user_preferences', array('userid' => $user->id, 'name' => $name))) {
39461de3 1867 if ($preference->value === $value and isset($user->preference[$name]) and $user->preference[$name] === $value) {
ac7af0da 1868 // Preference already set to this value.
a1244706 1869 return true;
1870 }
ac7af0da 1871 $DB->set_field('user_preferences', 'value', $value, array('id' => $preference->id));
70812e39 1872
1873 } else {
365a5941 1874 $preference = new stdClass();
39461de3 1875 $preference->userid = $user->id;
ae040d4b 1876 $preference->name = $name;
39461de3 1877 $preference->value = $value;
013376de 1878 $DB->insert_record('user_preferences', $preference);
2660377f 1879 }
1880
ac7af0da 1881 // Update value in cache.
39461de3
PS
1882 $user->preference[$name] = $value;
1883
ac7af0da 1884 // Set reload flag for other sessions.
39461de3 1885 mark_user_preferences_changed($user->id);
346c3e2f 1886
013376de 1887 return true;
2660377f 1888}
1889
1890/**
1891 * Sets a whole array of preferences for the current user
0d0a8bf6 1892 *
4d6b40a0 1893 * If a $user object is submitted it's 'preference' property is used for the preferences cache.
39461de3 1894 *
4d6b40a0
GGC
1895 * @package core
1896 * @category preference
1897 * @access public
1898 * @param array $prefarray An array of key/value pairs to be set
1899 * @param stdClass|int|null $user A moodle user object or id, null means current user
1900 * @return bool Always true or exception
2660377f 1901 */
39461de3 1902function set_user_preferences(array $prefarray, $user = null) {
2660377f 1903 foreach ($prefarray as $name => $value) {
39461de3 1904 set_user_preference($name, $value, $user);
2660377f 1905 }
013376de 1906 return true;
70812e39 1907}
1908
6eb3e776 1909/**
1910 * Unsets a preference completely by deleting it from the database
0d0a8bf6 1911 *
4d6b40a0 1912 * If a $user object is submitted it's 'preference' property is used for the preferences cache.
0d0a8bf6 1913 *
4d6b40a0
GGC
1914 * @package core
1915 * @category preference
1916 * @access public
1917 * @param string $name The key to unset as preference for the specified user
1918 * @param stdClass|int|null $user A moodle user object or id, null means current user
1919 * @throws coding_exception
1920 * @return bool Always true or exception
6eb3e776 1921 */
39461de3 1922function unset_user_preference($name, $user = null) {
ae040d4b 1923 global $USER, $DB;
6eb3e776 1924
39461de3
PS
1925 if (empty($name) or is_numeric($name) or $name === '_lastloaded') {
1926 throw new coding_exception('Invalid preference name in unset_user_preference() call');
1927 }
1928
1929 if (is_null($user)) {
1930 $user = $USER;
1931 } else if (isset($user->id)) {
ac7af0da 1932 // It is a valid object.
39461de3 1933 } else if (is_numeric($user)) {
ac7af0da 1934 $user = (object)array('id' => (int)$user);
346c3e2f 1935 } else {
39461de3 1936 throw new coding_exception('Invalid $user parameter in unset_user_preference() call');
346c3e2f 1937 }
1938
39461de3 1939 check_user_preferences_loaded($user);
013376de 1940
39461de3 1941 if (empty($user->id) or isguestuser($user->id)) {
ac7af0da 1942 // No permanent storage for not-logged-in user and guest.
39461de3
PS
1943 unset($user->preference[$name]);
1944 return true;
70812e39 1945 }
1946
ac7af0da
SH
1947 // Delete from DB.
1948 $DB->delete_records('user_preferences', array('userid' => $user->id, 'name' => $name));
39461de3 1949
ac7af0da 1950 // Delete the preference from cache.
39461de3
PS
1951 unset($user->preference[$name]);
1952
ac7af0da 1953 // Set reload flag for other sessions.
39461de3
PS
1954 mark_user_preferences_changed($user->id);
1955
013376de 1956 return true;
70812e39 1957}
1958
7cf1c7bd 1959/**
0d0a8bf6 1960 * Used to fetch user preference(s)
1961 *
7cf1c7bd 1962 * If no arguments are supplied this function will return
361855e6 1963 * all of the current user preferences as an array.
0d0a8bf6 1964 *
7cf1c7bd 1965 * If a name is specified then this function
1966 * attempts to return that particular preference value. If
1967 * none is found, then the optional value $default is returned,
ac7af0da 1968 * otherwise null.
0d0a8bf6 1969 *
4d6b40a0 1970 * If a $user object is submitted it's 'preference' property is used for the preferences cache.
39461de3 1971 *
4d6b40a0
GGC
1972 * @package core
1973 * @category preference
1974 * @access public
1975 * @param string $name Name of the key to use in finding a preference value
1976 * @param mixed|null $default Value to be returned if the $name key is not set in the user preferences
1977 * @param stdClass|int|null $user A moodle user object or id, null means current user
1978 * @throws coding_exception
1979 * @return string|mixed|null A string containing the value of a single preference. An
1980 * array with all of the preferences or null
7cf1c7bd 1981 */
39461de3
PS
1982function get_user_preferences($name = null, $default = null, $user = null) {
1983 global $USER;
70812e39 1984
39461de3 1985 if (is_null($name)) {
ac7af0da 1986 // All prefs.
39461de3
PS
1987 } else if (is_numeric($name) or $name === '_lastloaded') {
1988 throw new coding_exception('Invalid preference name in get_user_preferences() call');
1989 }
346c3e2f 1990
39461de3
PS
1991 if (is_null($user)) {
1992 $user = $USER;
1993 } else if (isset($user->id)) {
ac7af0da 1994 // Is a valid object.
39461de3 1995 } else if (is_numeric($user)) {
ac7af0da 1996 $user = (object)array('id' => (int)$user);
39461de3
PS
1997 } else {
1998 throw new coding_exception('Invalid $user parameter in get_user_preferences() call');
1999 }
2000
2001 check_user_preferences_loaded($user);
346c3e2f 2002
39461de3 2003 if (empty($name)) {
ac7af0da
SH
2004 // All values.
2005 return $user->preference;
39461de3 2006 } else if (isset($user->preference[$name])) {
ac7af0da
SH
2007 // The single string value.
2008 return $user->preference[$name];
346c3e2f 2009 } else {
ac7af0da
SH
2010 // Default value (null if not specified).
2011 return $default;
70812e39 2012 }
70812e39 2013}
2014
ac7af0da 2015// FUNCTIONS FOR HANDLING TIME.
39917a09 2016
7cf1c7bd 2017/**
c6d15803 2018 * Given date parts in user time produce a GMT timestamp.
7cf1c7bd 2019 *
9df12115
RT
2020 * @package core
2021 * @category time
68fbd8e1 2022 * @param int $year The year part to create timestamp of
2023 * @param int $month The month part to create timestamp of
2024 * @param int $day The day part to create timestamp of
2025 * @param int $hour The hour part to create timestamp of
2026 * @param int $minute The minute part to create timestamp of
2027 * @param int $second The second part to create timestamp of
9df12115
RT
2028 * @param int|float|string $timezone Timezone modifier, used to calculate GMT time offset.
2029 * if 99 then default user's timezone is used {@link http://docs.moodle.org/dev/Time_API#Timezone}
6a0bf5c4
RT
2030 * @param bool $applydst Toggle Daylight Saving Time, default true, will be
2031 * applied only if timezone is 99 or string.
9df12115 2032 * @return int GMT timestamp
7cf1c7bd 2033 */
9f1f6daf 2034function make_timestamp($year, $month=1, $day=1, $hour=0, $minute=0, $second=0, $timezone=99, $applydst=true) {
39917a09 2035
ac7af0da 2036 // Save input timezone, required for dst offset check.
6a0bf5c4 2037 $passedtimezone = $timezone;
33998d30 2038
dddb014a 2039 $timezone = get_user_timezone_offset($timezone);
2040
ac7af0da
SH
2041 if (abs($timezone) > 13) {
2042 // Server time.
68fbd8e1 2043 $time = mktime((int)$hour, (int)$minute, (int)$second, (int)$month, (int)$day, (int)$year);
03c17ddf 2044 } else {
68fbd8e1 2045 $time = gmmktime((int)$hour, (int)$minute, (int)$second, (int)$month, (int)$day, (int)$year);
196f2619 2046 $time = usertime($time, $timezone);
6a0bf5c4 2047
ac7af0da 2048 // Apply dst for string timezones or if 99 then try dst offset with user's default timezone.
6a0bf5c4
RT
2049 if ($applydst && ((99 == $passedtimezone) || !is_numeric($passedtimezone))) {
2050 $time -= dst_offset_on($time, $passedtimezone);
28c66824 2051 }
9f1f6daf 2052 }
2053
196f2619 2054 return $time;
85cafb3e 2055
39917a09 2056}
2057
7cf1c7bd 2058/**
0d0a8bf6 2059 * Format a date/time (seconds) as weeks, days, hours etc as needed
2060 *
7cf1c7bd 2061 * Given an amount of time in seconds, returns string
5602f7cf 2062 * formatted nicely as weeks, days, hours etc as needed
7cf1c7bd 2063 *
9df12115
RT
2064 * @package core
2065 * @category time
2f87145b 2066 * @uses MINSECS
2067 * @uses HOURSECS
2068 * @uses DAYSECS
5602f7cf 2069 * @uses YEARSECS
0d0a8bf6 2070 * @param int $totalsecs Time in seconds
ac7af0da 2071 * @param stdClass $str Should be a time object
0d0a8bf6 2072 * @return string A nicely formatted date/time string
7cf1c7bd 2073 */
ac7af0da 2074function format_time($totalsecs, $str = null) {
c7e3ac2a 2075
6b174680 2076 $totalsecs = abs($totalsecs);
c7e3ac2a 2077
ac7af0da
SH
2078 if (!$str) {
2079 // Create the str structure the slow way.
b85b25eb 2080 $str = new stdClass();
b0ccd3fb 2081 $str->day = get_string('day');
2082 $str->days = get_string('days');
2083 $str->hour = get_string('hour');
2084 $str->hours = get_string('hours');
2085 $str->min = get_string('min');
2086 $str->mins = get_string('mins');
2087 $str->sec = get_string('sec');
2088 $str->secs = get_string('secs');
5602f7cf 2089 $str->year = get_string('year');
2090 $str->years = get_string('years');
8dbed6be 2091 }
2092
5602f7cf 2093 $years = floor($totalsecs/YEARSECS);
2094 $remainder = $totalsecs - ($years*YEARSECS);
5602f7cf 2095 $days = floor($remainder/DAYSECS);
7a5672c9 2096 $remainder = $totalsecs - ($days*DAYSECS);
2097 $hours = floor($remainder/HOURSECS);
2098 $remainder = $remainder - ($hours*HOURSECS);
2099 $mins = floor($remainder/MINSECS);
2100 $secs = $remainder - ($mins*MINSECS);
8dbed6be 2101
2102 $ss = ($secs == 1) ? $str->sec : $str->secs;
2103 $sm = ($mins == 1) ? $str->min : $str->mins;
2104 $sh = ($hours == 1) ? $str->hour : $str->hours;
2105 $sd = ($days == 1) ? $str->day : $str->days;
5602f7cf 2106 $sy = ($years == 1) ? $str->year : $str->years;
8dbed6be 2107
5602f7cf 2108 $oyears = '';
b0ccd3fb 2109 $odays = '';
2110 $ohours = '';
2111 $omins = '';
2112 $osecs = '';
9c9f7d77 2113
ac7af0da
SH
2114 if ($years) {
2115 $oyears = $years .' '. $sy;
2116 }
2117 if ($days) {
2118 $odays = $days .' '. $sd;
2119 }
2120 if ($hours) {
2121 $ohours = $hours .' '. $sh;
2122 }
2123 if ($mins) {
2124 $omins = $mins .' '. $sm;
2125 }
2126 if ($secs) {
2127 $osecs = $secs .' '. $ss;
2128 }
2129
2130 if ($years) {
2131 return trim($oyears .' '. $odays);
2132 }
2133 if ($days) {
2134 return trim($odays .' '. $ohours);
2135 }
2136 if ($hours) {
2137 return trim($ohours .' '. $omins);
2138 }
2139 if ($mins) {
2140 return trim($omins .' '. $osecs);
2141 }
2142 if ($secs) {
2143 return $osecs;
2144 }
b0ccd3fb 2145 return get_string('now');
6b174680 2146}
f9903ed0 2147
7cf1c7bd 2148/**
f59ab4ad 2149 * Returns a formatted string that represents a date in user time.
7cf1c7bd 2150 *
9df12115
RT
2151 * @package core
2152 * @category time
0a0cf09a 2153 * @param int $date the timestamp in UTC, as obtained from the database.
2154 * @param string $format strftime format. You should probably get this using
9df12115 2155 * get_string('strftime...', 'langconfig');
f59ab4ad 2156 * @param int|float|string $timezone by default, uses the user's time zone. if numeric and
9df12115
RT
2157 * not 99 then daylight saving will not be added.
2158 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
0a0cf09a 2159 * @param bool $fixday If true (default) then the leading zero from %d is removed.
9df12115 2160 * If false then the leading zero is maintained.
d9498b38 2161 * @param bool $fixhour If true (default) then the leading zero from %I is removed.
0a0cf09a 2162 * @return string the formatted date/time.
7cf1c7bd 2163 */
d9498b38 2164function userdate($date, $format = '', $timezone = 99, $fixday = true, $fixhour = true) {
6eafa4dd 2165 $calendartype = \core_calendar\type_factory::get_calendar_instance();
f59ab4ad 2166 return $calendartype->timestamp_to_date_string($date, $format, $timezone, $fixday, $fixhour);
873960de 2167}
2168
15396bba
FM
2169/**
2170 * Returns a formatted date ensuring it is UTF-8.
2171 *
2172 * If we are running under Windows convert to Windows encoding and then back to UTF-8
2173 * (because it's impossible to specify UTF-8 to fetch locale info in Win32).
2174 *
2175 * This function does not do any calculation regarding the user preferences and should
2176 * therefore receive the final date timestamp, format and timezone. Timezone being only used
ac7af0da 2177 * to differentiate the use of server time or not (strftime() against gmstrftime()).
15396bba
FM
2178 *
2179 * @param int $date the timestamp.
2180 * @param string $format strftime format.
ac7af0da 2181 * @param int|float $tz the numerical timezone, typically returned by {@link get_user_timezone_offset()}.
15396bba 2182 * @return string the formatted date/time.
5bcfd504 2183 * @since Moodle 2.3.3
15396bba
FM
2184 */
2185function date_format_string($date, $format, $tz = 99) {
2186 global $CFG;
d61d3e82
RT
2187
2188 $localewincharset = null;
2189 // Get the calendar type user is using.
2190 if ($CFG->ostype == 'WINDOWS') {
2191 $calendartype = \core_calendar\type_factory::get_calendar_instance();
2192 $localewincharset = $calendartype->locale_win_charset();
2193 }
2194
15396bba 2195 if (abs($tz) > 13) {
d61d3e82 2196 if ($localewincharset) {
2f1e464a 2197 $format = core_text::convert($format, 'utf-8', $localewincharset);
15396bba 2198 $datestring = strftime($format, $date);
2f1e464a 2199 $datestring = core_text::convert($datestring, $localewincharset, 'utf-8');
15396bba
FM
2200 } else {
2201 $datestring = strftime($format, $date);
2202 }
2203 } else {
d61d3e82 2204 if ($localewincharset) {
2f1e464a 2205 $format = core_text::convert($format, 'utf-8', $localewincharset);
15396bba 2206 $datestring = gmstrftime($format, $date);
2f1e464a 2207 $datestring = core_text::convert($datestring, $localewincharset, 'utf-8');
15396bba
FM
2208 } else {
2209 $datestring = gmstrftime($format, $date);
2210 }
2211 }
2212 return $datestring;
2213}
2214
7cf1c7bd 2215/**
deed22ea
MN
2216 * Given a $time timestamp in GMT (seconds since epoch),
2217 * returns an array that represents the date in user time
7cf1c7bd 2218 *
9df12115
RT
2219 * @package core
2220 * @category time
deed22ea
MN
2221 * @uses HOURSECS
2222 * @param int $time Timestamp in GMT
2223 * @param float|int|string $timezone offset's time with timezone, if float and not 99, then no
2224 * dst offset is applied {@link http://docs.moodle.org/dev/Time_API#Timezone}
2225 * @return array An array that represents the date in user time
7cf1c7bd 2226 */
deed22ea
MN
2227function usergetdate($time, $timezone=99) {
2228
2229 // Save input timezone, required for dst offset check.
2230 $passedtimezone = $timezone;
2231
2232 $timezone = get_user_timezone_offset($timezone);
2233
2234 if (abs($timezone) > 13) {
2235 // Server time.
2236 return getdate($time);
2237 }
2238
2239 // Add daylight saving offset for string timezones only, as we can't get dst for
2240 // float values. if timezone is 99 (user default timezone), then try update dst.
2241 if ($passedtimezone == 99 || !is_numeric($passedtimezone)) {
2242 $time += dst_offset_on($time, $passedtimezone);
2243 }
2244
2245 $time += intval((float)$timezone * HOURSECS);
2246
2247 $datestring = gmstrftime('%B_%A_%j_%Y_%m_%w_%d_%H_%M_%S', $time);
2248
2249 // Be careful to ensure the returned array matches that produced by getdate() above.
2250 list(
2251 $getdate['month'],
2252 $getdate['weekday'],
2253 $getdate['yday'],
2254 $getdate['year'],
2255 $getdate['mon'],
2256 $getdate['wday'],
2257 $getdate['mday'],
2258 $getdate['hours'],
2259 $getdate['minutes'],
2260 $getdate['seconds']
2261 ) = explode('_', $datestring);
2262
2263 // Set correct datatype to match with getdate().
2264 $getdate['seconds'] = (int)$getdate['seconds'];
2265 $getdate['yday'] = (int)$getdate['yday'] - 1; // The function gmstrftime returns 0 through 365.
2266 $getdate['year'] = (int)$getdate['year'];
2267 $getdate['mon'] = (int)$getdate['mon'];
2268 $getdate['wday'] = (int)$getdate['wday'];
2269 $getdate['mday'] = (int)$getdate['mday'];
2270 $getdate['hours'] = (int)$getdate['hours'];
2271 $getdate['minutes'] = (int)$getdate['minutes'];
2272 return $getdate;
d552ead0 2273}
2274
7cf1c7bd 2275/**
2276 * Given a GMT timestamp (seconds since epoch), offsets it by
2277 * the timezone. eg 3pm in India is 3pm GMT - 7 * 3600 seconds
2278 *
9df12115
RT
2279 * @package core
2280 * @category time
2f87145b 2281 * @uses HOURSECS
9df12115
RT
2282 * @param int $date Timestamp in GMT
2283 * @param float|int|string $timezone timezone to calculate GMT time offset before
2284 * calculating user time, 99 is default user timezone
2285 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
c6d15803 2286 * @return int
7cf1c7bd 2287 */
d552ead0 2288function usertime($date, $timezone=99) {
a36166d3 2289
494b9296 2290 $timezone = get_user_timezone_offset($timezone);
2665e47a 2291
0431bd7c 2292 if (abs($timezone) > 13) {
d552ead0 2293 return $date;
2294 }
7a5672c9 2295 return $date - (int)($timezone * HOURSECS);
d552ead0 2296}
2297
8c3dba73 2298/**
2299 * Given a time, return the GMT timestamp of the most recent midnight
2300 * for the current user.
2301 *
9df12115
RT
2302 * @package core
2303 * @category time
e34d817e 2304 * @param int $date Timestamp in GMT
9df12115
RT
2305 * @param float|int|string $timezone timezone to calculate GMT time offset before
2306 * calculating user midnight time, 99 is default user timezone
2307 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
0d0a8bf6 2308 * @return int Returns a GMT timestamp
8c3dba73 2309 */
edf7fe8c 2310function usergetmidnight($date, $timezone=99) {
edf7fe8c 2311
edf7fe8c 2312 $userdate = usergetdate($date, $timezone);
4606d9bb 2313
ac7af0da 2314 // Time of midnight of this user's day, in GMT.
02f0527d 2315 return make_timestamp($userdate['year'], $userdate['mon'], $userdate['mday'], 0, 0, 0, $timezone);
edf7fe8c 2316
2317}
2318
7cf1c7bd 2319/**
2320 * Returns a string that prints the user's timezone
2321 *
9df12115
RT
2322 * @package core
2323 * @category time
2324 * @param float|int|string $timezone timezone to calculate GMT time offset before
2325 * calculating user timezone, 99 is default user timezone
2326 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
7cf1c7bd 2327 * @return string
2328 */
d552ead0 2329function usertimezone($timezone=99) {
d552ead0 2330
0c244315 2331 $tz = get_user_timezone($timezone);
f30fe8d0 2332
0c244315 2333 if (!is_float($tz)) {
2334 return $tz;
d552ead0 2335 }
0c244315 2336
ac7af0da
SH
2337 if (abs($tz) > 13) {
2338 // Server time.
0c244315 2339 return get_string('serverlocaltime');
2340 }
2341
ac7af0da
SH
2342 if ($tz == intval($tz)) {
2343 // Don't show .0 for whole hours.
0c244315 2344 $tz = intval($tz);
2345 }
2346
ac7af0da 2347 if ($tz == 0) {
61b420ac 2348 return 'UTC';
ac7af0da 2349 } else if ($tz > 0) {
61b420ac 2350 return 'UTC+'.$tz;
ac7af0da 2351 } else {
61b420ac 2352 return 'UTC'.$tz;
d552ead0 2353 }
e1ecf0a0 2354
f9903ed0 2355}
2356
7cf1c7bd 2357/**
2358 * Returns a float which represents the user's timezone difference from GMT in hours
2359 * Checks various settings and picks the most dominant of those which have a value
2360 *
9df12115
RT
2361 * @package core
2362 * @category time
2363 * @param float|int|string $tz timezone to calculate GMT time offset for user,
2364 * 99 is default user timezone
2365 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
0d0a8bf6 2366 * @return float
7cf1c7bd 2367 */
494b9296 2368function get_user_timezone_offset($tz = 99) {
e8904995 2369 $tz = get_user_timezone($tz);
c9e55a25 2370
7b9e355e 2371 if (is_float($tz)) {
2372 return $tz;
2373 } else {
e8904995 2374 $tzrecord = get_timezone_record($tz);
7b9e355e 2375 if (empty($tzrecord)) {
e8904995 2376 return 99.0;
2377 }
4f2dbde9 2378 return (float)$tzrecord->gmtoff / HOURMINS;
e8904995 2379 }
2380}
2381
61460dd6 2382/**
2383 * Returns an int which represents the systems's timezone difference from GMT in seconds
0d0a8bf6 2384 *
9df12115
RT
2385 * @package core
2386 * @category time
2387 * @param float|int|string $tz timezone for which offset is required.
2388 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
2389 * @return int|bool if found, false is timezone 99 or error
61460dd6 2390 */
2391function get_timezone_offset($tz) {
61460dd6 2392 if ($tz == 99) {
2393 return false;
2394 }
2395
2396 if (is_numeric($tz)) {
2397 return intval($tz * 60*60);
2398 }
2399
2400 if (!$tzrecord = get_timezone_record($tz)) {
2401 return false;
2402 }
2403 return intval($tzrecord->gmtoff * 60);
2404}
2405
bbd3f2c4 2406/**
b2b68362 2407 * Returns a float or a string which denotes the user's timezone
2408 * A float value means that a simple offset from GMT is used, while a string (it will be the name of a timezone in the database)
2409 * means that for this timezone there are also DST rules to be taken into account
2410 * Checks various settings and picks the most dominant of those which have a value
bbd3f2c4 2411 *
9df12115
RT
2412 * @package core
2413 * @category time
2414 * @param float|int|string $tz timezone to calculate GMT time offset before
2415 * calculating user timezone, 99 is default user timezone
2416 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
2417 * @return float|string
bbd3f2c4 2418 */
e8904995 2419function get_user_timezone($tz = 99) {
2420 global $USER, $CFG;
43b59916 2421
f30fe8d0 2422 $timezones = array(
e8904995 2423 $tz,
2424 isset($CFG->forcetimezone) ? $CFG->forcetimezone : 99,
43b59916 2425 isset($USER->timezone) ? $USER->timezone : 99,
2426 isset($CFG->timezone) ? $CFG->timezone : 99,
f30fe8d0 2427 );
43b59916 2428
e8904995 2429 $tz = 99;
43b59916 2430
ac7af0da
SH
2431 // Loop while $tz is, empty but not zero, or 99, and there is another timezone is the array.
2432 while (((empty($tz) && !is_numeric($tz)) || $tz == 99) && $next = each($timezones)) {
e8904995 2433 $tz = $next['value'];
43b59916 2434 }
e8904995 2435 return is_numeric($tz) ? (float) $tz : $tz;
43b59916 2436}
2437
bbd3f2c4 2438/**
f33e1ed4 2439 * Returns cached timezone record for given $timezonename
bbd3f2c4 2440 *
9df12115
RT
2441 * @package core
2442 * @param string $timezonename name of the timezone
2443 * @return stdClass|bool timezonerecord or false
bbd3f2c4 2444 */
43b59916 2445function get_timezone_record($timezonename) {
ac7af0da
SH
2446 global $DB;
2447 static $cache = null;
43b59916 2448
ac7af0da 2449 if ($cache === null) {
43b59916 2450 $cache = array();
2451 }
2452
8edffd15 2453 if (isset($cache[$timezonename])) {
43b59916 2454 return $cache[$timezonename];
f30fe8d0 2455 }
2456
f33e1ed4 2457 return $cache[$timezonename] = $DB->get_record_sql('SELECT * FROM {timezone}
daac3835 2458 WHERE name = ? ORDER BY year DESC', array($timezonename), IGNORE_MULTIPLE);
f30fe8d0 2459}
f9903ed0 2460
bbd3f2c4 2461/**
0d0a8bf6 2462 * Build and store the users Daylight Saving Time (DST) table
bbd3f2c4 2463 *
9df12115 2464 * @package core
ac7af0da
SH
2465 * @param int $fromyear Start year for the table, defaults to 1971
2466 * @param int $toyear End year for the table, defaults to 2035
2467 * @param int|float|string $strtimezone timezone to check if dst should be applied.
bbd3f2c4 2468 * @return bool
2469 */
ac7af0da
SH
2470function calculate_user_dst_table($fromyear = null, $toyear = null, $strtimezone = null) {
2471 global $SESSION, $DB;
85cafb3e 2472
33998d30 2473 $usertz = get_user_timezone($strtimezone);
7cb29a3d 2474
989585e9 2475 if (is_float($usertz)) {
ac7af0da 2476 // Trivial timezone, no DST.
989585e9 2477 return false;
2478 }
2479
2280ecf5 2480 if (!empty($SESSION->dst_offsettz) && $SESSION->dst_offsettz != $usertz) {
ac7af0da 2481 // We have pre-calculated values, but the user's effective TZ has changed in the meantime, so reset.
2280ecf5 2482 unset($SESSION->dst_offsets);
2483 unset($SESSION->dst_range);
830a2bbd 2484 }
2485
ac7af0da
SH
2486 if (!empty($SESSION->dst_offsets) && empty($fromyear) && empty($toyear)) {
2487 // Repeat calls which do not request specific year ranges stop here, we have already calculated the table.
2488 // This will be the return path most of the time, pretty light computationally.
830a2bbd 2489 return true;
85cafb3e 2490 }
2491
ac7af0da 2492 // Reaching here means we either need to extend our table or create it from scratch.
989585e9 2493
ac7af0da 2494 // Remember which TZ we calculated these changes for.
2280ecf5 2495 $SESSION->dst_offsettz = $usertz;
989585e9 2496
ac7af0da
SH
2497 if (empty($SESSION->dst_offsets)) {
2498 // If we 're creating from scratch, put the two guard elements in there.
2499 $SESSION->dst_offsets = array(1 => null, 0 => null);
830a2bbd 2500 }
ac7af0da
SH
2501 if (empty($SESSION->dst_range)) {
2502 // If creating from scratch.
2503 $from = max((empty($fromyear) ? intval(date('Y')) - 3 : $fromyear), 1971);
2504 $to = min((empty($toyear) ? intval(date('Y')) + 3 : $toyear), 2035);
830a2bbd 2505
ac7af0da 2506 // Fill in the array with the extra years we need to process.
830a2bbd 2507 $yearstoprocess = array();
ac7af0da 2508 for ($i = $from; $i <= $to; ++$i) {
830a2bbd 2509 $yearstoprocess[] = $i;
2510 }
2511
ac7af0da 2512 // Take note of which years we have processed for future calls.
2280ecf5 2513 $SESSION->dst_range = array($from, $to);
ac7af0da
SH
2514 } else {
2515 // If needing to extend the table, do the same.
830a2bbd 2516 $yearstoprocess = array();
2517
ac7af0da
SH
2518 $from = max((empty($fromyear) ? $SESSION->dst_range[0] : $fromyear), 1971);
2519 $to = min((empty($toyear) ? $SESSION->dst_range[1] : $toyear), 2035);
830a2bbd 2520
ac7af0da
SH
2521 if ($from < $SESSION->dst_range[0]) {
2522 // Take note of which years we need to process and then note that we have processed them for future calls.
2523 for ($i = $from; $i < $SESSION->dst_range[0]; ++$i) {
830a2bbd 2524 $yearstoprocess[] = $i;
2525 }
2280ecf5 2526 $SESSION->dst_range[0] = $from;
830a2bbd 2527 }
ac7af0da
SH
2528 if ($to > $SESSION->dst_range[1]) {
2529 // Take note of which years we need to process and then note that we have processed them for future calls.
2530 for ($i = $SESSION->dst_range[1] + 1; $i <= $to; ++$i) {
830a2bbd 2531 $yearstoprocess[] = $i;
2532 }
2280ecf5 2533 $SESSION->dst_range[1] = $to;
830a2bbd 2534 }
2535 }
2536
ac7af0da
SH
2537 if (empty($yearstoprocess)) {
2538 // This means that there was a call requesting a SMALLER range than we have already calculated.
830a2bbd 2539 return true;
2540 }
2541
2542 // From now on, we know that the array has at least the two guard elements, and $yearstoprocess has the years we need
2543 // Also, the array is sorted in descending timestamp order!
2544
ac7af0da 2545 // Get DB data.
6a5dc27c 2546
ac7af0da
SH
2547 static $presetscache = array();
2548 if (!isset($presetscache[$usertz])) {
2549 $presetscache[$usertz] = $DB->get_records('timezone', array('name' => $usertz),
2550 'year DESC', 'year, gmtoff, dstoff, dst_month, dst_startday, dst_weekday, dst_skipweeks, dst_time, std_month, '.
2551 'std_startday, std_weekday, std_skipweeks, std_time');
6a5dc27c 2552 }
ac7af0da 2553 if (empty($presetscache[$usertz])) {
e789650d 2554 return false;
2555 }
57f1191c 2556
ac7af0da 2557 // Remove ending guard (first element of the array).
2280ecf5 2558 reset($SESSION->dst_offsets);
2559 unset($SESSION->dst_offsets[key($SESSION->dst_offsets)]);
830a2bbd 2560
ac7af0da
SH
2561 // Add all required change timestamps.
2562 foreach ($yearstoprocess as $y) {
2563 // Find the record which is in effect for the year $y.
2564 foreach ($presetscache[$usertz] as $year => $preset) {
2565 if ($year <= $y) {
830a2bbd 2566 break;
c9e72798 2567 }
830a2bbd 2568 }
2569
2570 $changes = dst_changes_for_year($y, $preset);
2571
ac7af0da 2572 if ($changes === null) {
830a2bbd 2573 continue;
2574 }
ac7af0da 2575 if ($changes['dst'] != 0) {
2280ecf5 2576 $SESSION->dst_offsets[$changes['dst']] = $preset->dstoff * MINSECS;
830a2bbd 2577 }
ac7af0da 2578 if ($changes['std'] != 0) {
2280ecf5 2579 $SESSION->dst_offsets[$changes['std']] = 0;
c9e72798 2580 }
85cafb3e 2581 }
42d36497 2582
ac7af0da 2583 // Put in a guard element at the top.
2280ecf5 2584 $maxtimestamp = max(array_keys($SESSION->dst_offsets));
ac7af0da 2585 $SESSION->dst_offsets[($maxtimestamp + DAYSECS)] = null; // DAYSECS is arbitrary, any "small" number will do.
830a2bbd 2586
ac7af0da 2587 // Sort again.
2280ecf5 2588 krsort($SESSION->dst_offsets);
830a2bbd 2589
e789650d 2590 return true;
2591}
42d36497 2592
0d0a8bf6 2593/**
2594 * Calculates the required DST change and returns a Timestamp Array
2595 *
9df12115
RT
2596 * @package core
2597 * @category time
0d0a8bf6 2598 * @uses HOURSECS
2599 * @uses MINSECS
9df12115 2600 * @param int|string $year Int or String Year to focus on
0d0a8bf6 2601 * @param object $timezone Instatiated Timezone object
ac7af0da 2602 * @return array|null Array dst => xx, 0 => xx, std => yy, 1 => yy or null
0d0a8bf6 2603 */
e789650d 2604function dst_changes_for_year($year, $timezone) {
7cb29a3d 2605
ac7af0da
SH
2606 if ($timezone->dst_startday == 0 && $timezone->dst_weekday == 0 &&
2607 $timezone->std_startday == 0 && $timezone->std_weekday == 0) {
2608 return null;
42d36497 2609 }
7cb29a3d 2610
e789650d 2611 $monthdaydst = find_day_in_month($timezone->dst_startday, $timezone->dst_weekday, $timezone->dst_month, $year);
2612 $monthdaystd = find_day_in_month($timezone->std_startday, $timezone->std_weekday, $timezone->std_month, $year);
2613
ac7af0da
SH
2614 list($dsthour, $dstmin) = explode(':', $timezone->dst_time);
2615 list($stdhour, $stdmin) = explode(':', $timezone->std_time);
d2a9f7cc 2616
2f00e1b2
MN
2617 $timedst = make_timestamp($year, $timezone->dst_month, $monthdaydst, 0, 0, 0, 99, false);
2618 $timestd = make_timestamp($year, $timezone->std_month, $monthdaystd, 0, 0, 0, 99, false);
830a2bbd 2619
2620 // Instead of putting hour and minute in make_timestamp(), we add them afterwards.
2621 // This has the advantage of being able to have negative values for hour, i.e. for timezones
2622 // where GMT time would be in the PREVIOUS day than the local one on which DST changes.
2623
ac7af0da
SH
2624 $timedst += $dsthour * HOURSECS + $dstmin * MINSECS;
2625 $timestd += $stdhour * HOURSECS + $stdmin * MINSECS;
42d36497 2626
e789650d 2627 return array('dst' => $timedst, 0 => $timedst, 'std' => $timestd, 1 => $timestd);
42d36497 2628}
2629
0d0a8bf6 2630/**
efb8c375 2631 * Calculates the Daylight Saving Offset for a given date/time (timestamp)
6a0bf5c4 2632 * - Note: Daylight saving only works for string timezones and not for float.
0d0a8bf6 2633 *
9df12115
RT
2634 * @package core
2635 * @category time
0d0a8bf6 2636 * @param int $time must NOT be compensated at all, it has to be a pure timestamp
9df12115
RT
2637 * @param int|float|string $strtimezone timezone for which offset is expected, if 99 or null
2638 * then user's default timezone is used. {@link http://docs.moodle.org/dev/Time_API#Timezone}
0d0a8bf6 2639 * @return int
2640 */
ac7af0da 2641function dst_offset_on($time, $strtimezone = null) {
2280ecf5 2642 global $SESSION;
02f0527d 2643
ac7af0da 2644 if (!calculate_user_dst_table(null, null, $strtimezone) || empty($SESSION->dst_offsets)) {
c9e72798 2645 return 0;
85cafb3e 2646 }
2647
2280ecf5 2648 reset($SESSION->dst_offsets);
ac7af0da
SH
2649 while (list($from, $offset) = each($SESSION->dst_offsets)) {
2650 if ($from <= $time) {
c9e72798 2651 break;
2652 }
2653 }
2654
ac7af0da
SH
2655 // This is the normal return path.
2656 if ($offset !== null) {
830a2bbd 2657 return $offset;
02f0527d 2658 }
02f0527d 2659
830a2bbd 2660 // Reaching this point means we haven't calculated far enough, do it now:
2661 // Calculate extra DST changes if needed and recurse. The recursion always
2662 // moves toward the stopping condition, so will always end.
2663
ac7af0da
SH
2664 if ($from == 0) {
2665 // We need a year smaller than $SESSION->dst_range[0].
2666 if ($SESSION->dst_range[0] == 1971) {
830a2bbd 2667 return 0;
2668 }
ac7af0da 2669 calculate_user_dst_table($SESSION->dst_range[0] - 5, null, $strtimezone);
94c82430 2670 return dst_offset_on($time, $strtimezone);
ac7af0da
SH
2671 } else {
2672 // We need a year larger than $SESSION->dst_range[1].
2673 if ($SESSION->dst_range[1] == 2035) {
830a2bbd 2674 return 0;
2675 }
ac7af0da 2676 calculate_user_dst_table(null, $SESSION->dst_range[1] + 5, $strtimezone);
94c82430 2677 return dst_offset_on($time, $strtimezone);
830a2bbd 2678 }
85cafb3e 2679}
02f0527d 2680
0d0a8bf6 2681/**
9df12115 2682 * Calculates when the day appears in specific month
0d0a8bf6 2683 *
9df12115
RT
2684 * @package core
2685 * @category time
2686 * @param int $startday starting day of the month
2687 * @param int $weekday The day when week starts (normally taken from user preferences)
2688 * @param int $month The month whose day is sought
2689 * @param int $year The year of the month whose day is sought
0d0a8bf6 2690 * @return int
2691 */
28902d99 2692function find_day_in_month($startday, $weekday, $month, $year) {
da304137 2693 $calendartype = \core_calendar\type_factory::get_calendar_instance();
8dc3f6cf 2694
2695 $daysinmonth = days_in_month($month, $year);
da304137 2696 $daysinweek = count($calendartype->get_weekdays());
8dc3f6cf 2697
ac7af0da 2698 if ($weekday == -1) {
28902d99 2699 // Don't care about weekday, so return:
2700 // abs($startday) if $startday != -1
ac7af0da 2701 // $daysinmonth otherwise.
28902d99 2702 return ($startday == -1) ? $daysinmonth : abs($startday);
8dc3f6cf 2703 }
2704
ac7af0da 2705 // From now on we 're looking for a specific weekday.
ac7af0da
SH
2706 // Give "end of month" its actual value, since we know it.
2707 if ($startday == -1) {
28902d99 2708 $startday = -1 * $daysinmonth;
2709 }
2710
ac7af0da 2711 // Starting from day $startday, the sign is the direction.
ac7af0da 2712 if ($startday < 1) {
28902d99 2713 $startday = abs($startday);
da304137 2714 $lastmonthweekday = dayofweek($daysinmonth, $month, $year);
8dc3f6cf 2715
ac7af0da 2716 // This is the last such weekday of the month.
8dc3f6cf 2717 $lastinmonth = $daysinmonth + $weekday - $lastmonthweekday;
ac7af0da 2718 if ($lastinmonth > $daysinmonth) {
da304137 2719 $lastinmonth -= $daysinweek;
42d36497 2720 }
8dc3f6cf 2721
ac7af0da
SH
2722 // Find the first such weekday <= $startday.
2723 while ($lastinmonth > $startday) {
da304137 2724 $lastinmonth -= $daysinweek;
42d36497 2725 }
8dc3f6cf 2726
2727 return $lastinmonth;
ac7af0da 2728 } else {
da304137 2729 $indexweekday = dayofweek($startday, $month, $year);
42d36497 2730
8dc3f6cf 2731 $diff = $weekday - $indexweekday;
ac7af0da 2732 if ($diff < 0) {
da304137 2733 $diff += $daysinweek;
42d36497 2734 }
42d36497 2735
ac7af0da 2736 // This is the first such weekday of the month equal to or after $startday.
28902d99 2737 $firstfromindex = $startday + $diff;
42d36497 2738
8dc3f6cf 2739 return $firstfromindex;
8dc3f6cf 2740 }
42d36497 2741}
2742
bbd3f2c4 2743/**
2744 * Calculate the number of days in a given month
2745 *
9df12115
RT
2746 * @package core
2747 * @category time
bbd3f2c4 2748 * @param int $month The month whose day count is sought
2749 * @param int $year The year of the month whose day count is sought
2750 * @return int
2751 */
42d36497 2752function days_in_month($month, $year) {
da304137
MN
2753 $calendartype = \core_calendar\type_factory::get_calendar_instance();
2754 return $calendartype->get_num_days_in_month($year, $month);
42d36497 2755}
2756
bbd3f2c4 2757/**
2758 * Calculate the position in the week of a specific calendar day
2759 *
9df12115
RT
2760 * @package core
2761 * @category time
bbd3f2c4 2762 * @param int $day The day of the date whose position in the week is sought
2763 * @param int $month The month of the date whose position in the week is sought
2764 * @param int $year The year of the date whose position in the week is sought
2765 * @return int
2766 */
8dc3f6cf 2767function dayofweek($day, $month, $year) {
da304137
MN
2768 $calendartype = \core_calendar\type_factory::get_calendar_instance();
2769 return $calendartype->get_weekday($year, $month, $day);
8dc3f6cf 2770}
2771
ac7af0da 2772// USER AUTHENTICATION AND LOGIN.
f9903ed0 2773
93f66983 2774/**
2775 * Returns full login url.
2776 *
93f66983 2777 * @return string login url
2778 */
999b54af 2779function get_login_url() {
93f66983 2780 global $CFG;
2781
999b54af 2782 $url = "$CFG->wwwroot/login/index.php";
93f66983 2783
999b54af
PS
2784 if (!empty($CFG->loginhttps)) {
2785 $url = str_replace('http:', 'https:', $url);
93f66983 2786 }
2787
2788 return $url;
2789}
2790
7cf1c7bd 2791/**
ec81373f 2792 * This function checks that the current user is logged in and has the
2793 * required privileges
2794 *
7cf1c7bd 2795 * This function checks that the current user is logged in, and optionally
ec81373f 2796 * whether they are allowed to be in a particular course and view a particular
2797 * course module.
2798 * If they are not logged in, then it redirects them to the site login unless
d2a9f7cc 2799 * $autologinguest is set and {@link $CFG}->autologinguests is set to 1 in which
ec81373f 2800 * case they are automatically logged in as guests.
2801 * If $courseid is given and the user is not enrolled in that course then the
2802 * user is redirected to the course enrolment page.
efb8c375 2803 * If $cm is given and the course module is hidden and the user is not a teacher
ec81373f 2804 * in the course then the user is redirected to the course home page.
7cf1c7bd 2805 *
191b267b 2806 * When $cm parameter specified, this function sets page layout to 'module'.
4f0c2d00 2807 * You need to change it manually later if some other layout needed.
191b267b 2808 *
f76249cc
PS
2809 * @package core_access
2810 * @category access
2811 *
33ebaf7c 2812 * @param mixed $courseorid id of the course or course object
0d0a8bf6 2813 * @param bool $autologinguest default true
bbd3f2c4 2814 * @param object $cm course module object
f4013c10 2815 * @param bool $setwantsurltome Define if we want to set $SESSION->wantsurl, defaults to
2816 * true. Used to avoid (=false) some scripts (file.php...) to set that variable,
2817 * in order to keep redirects working properly. MDL-14495
df997f84 2818 * @param bool $preventredirect set to true in scripts that can not redirect (CLI, rss feeds, etc.), throws exceptions
0d0a8bf6 2819 * @return mixed Void, exit, and die depending on path
ac7af0da
SH
2820 * @throws coding_exception
2821 * @throws require_login_exception
7cf1c7bd 2822 */
ac7af0da 2823function require_login($courseorid = null, $autologinguest = true, $cm = null, $setwantsurltome = true, $preventredirect = false) {
f0202ae9 2824 global $CFG, $SESSION, $USER, $PAGE, $SITE, $DB, $OUTPUT;
d8ba183c 2825
f22f1caf
PS
2826 // Must not redirect when byteserving already started.
2827 if (!empty($_SERVER['HTTP_RANGE'])) {
2828 $preventredirect = true;
2829 }
2830
ac7af0da 2831 // Setup global $COURSE, themes, language and locale.
c13a5e71 2832 if (!empty($courseorid)) {
2833 if (is_object($courseorid)) {
2834 $course = $courseorid;
2835 } else if ($courseorid == SITEID) {
2836 $course = clone($SITE);
2837 } else {
74df2951 2838 $course = $DB->get_record('course', array('id' => $courseorid), '*', MUST_EXIST);
c13a5e71 2839 }
95d28870 2840 if ($cm) {
df997f84
PS
2841 if ($cm->course != $course->id) {
2842 throw new coding_exception('course and cm parameters in require_login() call do not match!!');
2843 }
ac7af0da 2844 // Make sure we have a $cm from get_fast_modinfo as this contains activity access details.
47148151 2845 if (!($cm instanceof cm_info)) {
ac7af0da 2846 // Note: nearly all pages call get_fast_modinfo anyway and it does not make any
0d8b6a69 2847 // db queries so this is not really a performance concern, however it is obviously
2848 // better if you use get_fast_modinfo to get the cm before calling this.
2849 $modinfo = get_fast_modinfo($course);
2850 $cm = $modinfo->get_cm($cm->id);
2851 }
ac7af0da 2852 $PAGE->set_cm($cm, $course); // Set's up global $COURSE.
191b267b 2853 $PAGE->set_pagelayout('incourse');
95d28870 2854 } else {
ac7af0da 2855 $PAGE->set_course($course); // Set's up global $COURSE.
95d28870 2856 }
e88462a0 2857 } else {
ac7af0da 2858 // Do not touch global $COURSE via $PAGE->set_course(),
df997f84
PS
2859 // the reasons is we need to be able to call require_login() at any time!!
2860 $course = $SITE;
2861 if ($cm) {
2862 throw new coding_exception('cm parameter in require_login() requires valid course parameter!');
2863 }
c13a5e71 2864 }
be933850 2865
aa4a6566
SH
2866 // If this is an AJAX request and $setwantsurltome is true then we need to override it and set it to false.
2867 // Otherwise the AJAX request URL will be set to $SESSION->wantsurl and events such as self enrolment in the future
2868 // risk leading the user back to the AJAX request URL.
2869 if ($setwantsurltome && defined('AJAX_SCRIPT') && AJAX_SCRIPT) {
2870 $setwantsurltome = false;
2871 }
2872
12fc11e7 2873 // Redirect to the login page if session has expired, only with dbsessions enabled (MDL-35029) to maintain current behaviour.
8cd6d1aa 2874 if ((!isloggedin() or isguestuser()) && !empty($SESSION->has_timed_out) && !$preventredirect && !empty($CFG->dbsessions)) {
12fc11e7
DM
2875 if ($setwantsurltome) {
2876 $SESSION->wantsurl = qualified_me();
2877 }
2878 redirect(get_login_url());
2879 }
2880
ac7af0da 2881 // If the user is not even logged in yet then make sure they are.
083c3743 2882 if (!isloggedin()) {
df997f84 2883 if ($autologinguest and !empty($CFG->guestloginbutton) and !empty($CFG->autologinguests)) {
999b54af 2884 if (!$guest = get_complete_user_data('id', $CFG->siteguest)) {
ac7af0da 2885 // Misconfigured site guest, just redirect to login page.
999b54af 2886 redirect(get_login_url());
ac7af0da 2887 exit; // Never reached.
df997f84 2888 }
999b54af 2889 $lang = isset($SESSION->lang) ? $SESSION->lang : $CFG->lang;
0342fc36 2890 complete_user_login($guest);
d9e07264 2891 $USER->autologinguest = true;
999b54af 2892 $SESSION->lang = $lang;
8a33e371 2893 } else {
ac7af0da 2894 // NOTE: $USER->site check was obsoleted by session test cookie, $USER->confirmed test is in login/index.php.
999b54af
PS
2895 if ($preventredirect) {
2896 throw new require_login_exception('You are not logged in');
2897 }
2898
2899 if ($setwantsurltome) {
f0202ae9 2900 $SESSION->wantsurl = qualified_me();
999b54af
PS
2901 }
2902 if (!empty($_SERVER['HTTP_REFERER'])) {
2903 $SESSION->fromurl = $_SERVER['HTTP_REFERER'];
2904 }
2905 redirect(get_login_url());
ac7af0da 2906 exit; // Never reached.
8a33e371 2907 }
f9903ed0 2908 }
808a3baa 2909
ac7af0da 2910 // Loginas as redirection if needed.
d79d5ac2 2911 if ($course->id != SITEID and \core\session\manager::is_loggedinas()) {
f6f66b03 2912 if ($USER->loginascontext->contextlevel == CONTEXT_COURSE) {
df997f84 2913 if ($USER->loginascontext->instanceid != $course->id) {
3887fe4a 2914 print_error('loginasonecourse', '', $CFG->wwwroot.'/course/view.php?id='.$USER->loginascontext->instanceid);
5e623a33 2915 }
f6f66b03 2916 }
2917 }
2918
ac7af0da 2919 // Check whether the user should be changing password (but only if it is REALLY them).
d79d5ac2 2920 if (get_user_preferences('auth_forcepasswordchange') && !\core\session\manager::is_loggedinas()) {
21e2dcd9 2921 $userauth = get_auth_plugin($USER->auth);
df997f84 2922 if ($userauth->can_change_password() and !$preventredirect) {
af572078 2923 if ($setwantsurltome) {
f0202ae9 2924 $SESSION->wantsurl = qualified_me();
af572078 2925 }
80274abf 2926 if ($changeurl = $userauth->change_password_url()) {
ac7af0da 2927 // Use plugin custom url.
80274abf 2928 redirect($changeurl);
1437f0a5 2929 } else {
ac7af0da 2930 // Use moodle internal method.
9696bd89 2931 if (empty($CFG->loginhttps)) {
2932 redirect($CFG->wwwroot .'/login/change_password.php');
2933 } else {
ac7af0da 2934 $wwwroot = str_replace('http:', 'https:', $CFG->wwwroot);
9696bd89 2935 redirect($wwwroot .'/login/change_password.php');
2936 }
1437f0a5 2937 }
d35757eb 2938 } else {
a8ee7194 2939 print_error('nopasswordchangeforced', 'auth');
d35757eb 2940 }
2941 }
083c3743 2942
ac7af0da 2943 // Check that the user account is properly set up.
808a3baa 2944 if (user_not_fully_set_up($USER)) {
df997f84
PS
2945 if ($preventredirect) {
2946 throw new require_login_exception('User not fully set-up');
2947 }
af572078 2948 if ($setwantsurltome) {
f0202ae9 2949 $SESSION->wantsurl = qualified_me();
af572078 2950 }
b0ccd3fb 2951 redirect($CFG->wwwroot .'/user/edit.php?id='. $USER->id .'&amp;course='. SITEID);
808a3baa 2952 }
d8ba183c 2953
df997f84 2954 // Make sure the USER has a sesskey set up. Used for CSRF protection.
04280e85 2955 sesskey();
366dfa60 2956
ac7af0da 2957 // Do not bother admins with any formalities.
df997f84 2958 if (is_siteadmin()) {
ac7af0da 2959 // Set accesstime or the user will appear offline which messes up messaging.
1560760f 2960 user_accesstime_log($course->id);
df997f84
PS
2961 return;
2962 }
2963
ac7af0da 2964 // Check that the user has agreed to a site policy if there is one - do not test in case of admins.
b593d49d
PS
2965 if (!$USER->policyagreed and !is_siteadmin()) {
2966 if (!empty($CFG->sitepolicy) and !isguestuser()) {
2967 if ($preventredirect) {
2968 throw new require_login_exception('Policy not agreed');
2969 }
af572078 2970 if ($setwantsurltome) {
f0202ae9 2971 $SESSION->wantsurl = qualified_me();
af572078 2972 }
b593d49d
PS
2973 redirect($CFG->wwwroot .'/user/policy.php');
2974 } else if (!empty($CFG->sitepolicyguest) and isguestuser()) {
2975 if ($preventredirect) {
2976 throw new require_login_exception('Policy not agreed');
2977 }
af572078 2978 if ($setwantsurltome) {
f0202ae9 2979 $SESSION->wantsurl = qualified_me();
af572078 2980 }
027a1604 2981 redirect($CFG->wwwroot .'/user/policy.php');
027a1604 2982 }
1695b680 2983 }
2984
ac7af0da 2985 // Fetch the system context, the course context, and prefetch its child contexts.
b0c6dc1c
AG
2986 $sysctx = context_system::instance();
2987 $coursecontext = context_course::instance($course->id, MUST_EXIST);
df997f84 2988 if ($cm) {
b0c6dc1c 2989 $cmcontext = context_module::instance($cm->id, MUST_EXIST);
df997f84
PS
2990 } else {
2991 $cmcontext = null;
2992 }
21e2dcd9 2993
ac7af0da 2994 // If the site is currently under maintenance, then print a message.
4fe2250a 2995 if (!empty($CFG->maintenance_enabled) and !has_capability('moodle/site:config', $sysctx)) {
df997f84
PS
2996 if ($preventredirect) {
2997 throw new require_login_exception('Maintenance in progress');
2998 }
2999
4fe2250a 3000 print_maintenance_message();
027a1604 3001 }
3002
ac7af0da 3003 // Make sure the course itself is not hidden.
df997f84 3004 if ($course->id == SITEID) {
ac7af0da 3005 // Frontpage can not be hidden.
df997f84 3006 } else {
f5c1e621 3007 if (is_role_switched($course->id)) {
ac7af0da 3008 // When switching roles ignore the hidden flag - user had to be in course to do the switch.
df997f84
PS
3009 } else {
3010 if (!$course->visible and !has_capability('moodle/course:viewhiddencourses', $coursecontext)) {
ac7af0da
SH
3011 // Originally there was also test of parent category visibility, BUT is was very slow in complex queries
3012 // involving "my courses" now it is also possible to simply hide all courses user is not enrolled in :-).
df997f84
PS
3013 if ($preventredirect) {
3014 throw new require_login_exception('Course is hidden');
3015 }
ac7af0da
SH
3016 // We need to override the navigation URL as the course won't have been added to the navigation and thus
3017 // the navigation will mess up when trying to find it.
a0a39b0d 3018 navigation_node::override_active_url(new moodle_url('/'));
df997f84
PS
3019 notice(get_string('coursehidden'), $CFG->wwwroot .'/');
3020 }
3021 }
3022 }
3023
ac7af0da 3024 // Is the user enrolled?
df997f84 3025 if ($course->id == SITEID) {
ac7af0da 3026 // Everybody is enrolled on the frontpage.
df997f84 3027 } else {
d79d5ac2 3028 if (\core\session\manager::is_loggedinas()) {
ac7af0da 3029 // Make sure the REAL person can access this course first.
d79d5ac2 3030 $realuser = \core\session\manager::get_realuser();
ac7af0da
SH
3031 if (!is_enrolled($coursecontext, $realuser->id, '', true) and
3032 !is_viewing($coursecontext, $realuser->id) and !is_siteadmin($realuser->id)) {
df997f84
PS
3033 if ($preventredirect) {
3034 throw new require_login_exception('Invalid course login-as access');
3035 }
3036 echo $OUTPUT->header();
3037 notice(get_string('studentnotallowed', '', fullname($USER, true)), $CFG->wwwroot .'/');
3038 }
3039 }
3040
df997f84
PS
3041 $access = false;
3042
dbd7282c 3043 if (is_role_switched($course->id)) {
ac7af0da 3044 // Ok, user had to be inside this course before the switch.
dbd7282c
PS
3045 $access = true;
3046
3047 } else if (is_viewing($coursecontext, $USER)) {