Merge branch 'wip-MDL-40356-master' of git://github.com/abgreeve/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
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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');
061e6b28 417/**
418 * True if module supports groupmembersonly (which no longer exists)
419 * @deprecated Since Moodle 2.8
420 */
42f103be 421define('FEATURE_GROUPMEMBERSONLY', 'groupmembersonly');
422
aa54ed7b 423/** Type of module */
424define('FEATURE_MOD_ARCHETYPE', 'mod_archetype');
42f103be 425/** True if module supports intro editor */
dc5c2bd9 426define('FEATURE_MOD_INTRO', 'mod_intro');
42f103be 427/** True if module has default completion */
428define('FEATURE_MODEDIT_DEFAULT_COMPLETION', 'modedit_default_completion');
49f6e5f4 429
1bcb7eb5 430define('FEATURE_COMMENT', 'comment');
431
6c5fcef7 432define('FEATURE_RATE', 'rate');
4bfdcfcf
EL
433/** True if module supports backup/restore of moodle2 format */
434define('FEATURE_BACKUP_MOODLE2', 'backup_moodle2');
a09aeee4 435
8c40662e 436/** True if module can show description on course main page */
437define('FEATURE_SHOW_DESCRIPTION', 'showdescription');
438
b07ef13b
DP
439/** True if module uses the question bank */
440define('FEATURE_USES_QUESTIONS', 'usesquestions');
441
aa54ed7b 442/** Unspecified module archetype */
443define('MOD_ARCHETYPE_OTHER', 0);
444/** Resource-like type module */
445define('MOD_ARCHETYPE_RESOURCE', 1);
efb8c375 446/** Assignment module archetype */
aa54ed7b 447define('MOD_ARCHETYPE_ASSIGNMENT', 2);
5813c7f7 448/** System (not user-addable) module archetype */
449define('MOD_ARCHETYPE_SYSTEM', 3);
aa54ed7b 450
50ae8814
MN
451/** Return this from modname_get_types callback to use default display in activity chooser */
452define('MOD_SUBTYPE_NO_CHILDREN', 'modsubtypenochildren');
453
eec99048 454/**
455 * Security token used for allowing access
456 * from external application such as web services.
457 * Scripts do not use any session, performance is relatively
458 * low because we need to load access info in each request.
efb8c375 459 * Scripts are executed in parallel.
eec99048 460 */
461define('EXTERNAL_TOKEN_PERMANENT', 0);
462
463/**
464 * Security token used for allowing access
465 * of embedded applications, the code is executed in the
466 * active user session. Token is invalidated after user logs out.
467 * Scripts are executed serially - normal session locking is used.
468 */
469define('EXTERNAL_TOKEN_EMBEDDED', 1);
49f6e5f4 470
4766a50c
SH
471/**
472 * The home page should be the site home
473 */
474define('HOMEPAGE_SITE', 0);
475/**
476 * The home page should be the users my page
477 */
478define('HOMEPAGE_MY', 1);
479/**
480 * The home page can be chosen by the user
481 */
482define('HOMEPAGE_USER', 2);
fcce139a 483
94788de2 484/**
485 * Hub directory url (should be moodle.org)
486 */
487define('HUB_HUBDIRECTORYURL', "http://hubdirectory.moodle.org");
488
489
490/**
491 * Moodle.org url (should be moodle.org)
492 */
493define('HUB_MOODLEORGHUBURL', "http://hub.moodle.org");
494
c1b65883
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495/**
496 * Moodle mobile app service name
497 */
498define('MOODLE_OFFICIAL_MOBILE_SERVICE', 'moodle_mobile_app');
94788de2 499
bc8da017
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500/**
501 * Indicates the user has the capabilities required to ignore activity and course file size restrictions
502 */
503define('USER_CAN_IGNORE_FILE_SIZE_LIMITS', -1);
504
1f09018a 505/**
ac7af0da
SH
506 * Course display settings: display all sections on one page.
507 */
508define('COURSE_DISPLAY_SINGLEPAGE', 0);
509/**
510 * Course display settings: split pages into a page per section.
1f09018a 511 */
ac7af0da 512define('COURSE_DISPLAY_MULTIPAGE', 1);
1f09018a 513
ec2d8ceb 514/**
ac7af0da 515 * Authentication constant: String used in password field when password is not stored.
ec2d8ceb 516 */
ac7af0da 517define('AUTH_PASSWORD_NOT_CACHED', 'not cached');
ec2d8ceb 518
ac7af0da 519// PARAMETER HANDLING.
6b174680 520
e0d346ff 521/**
361855e6 522 * Returns a particular value for the named variable, taken from
523 * POST or GET. If the parameter doesn't exist then an error is
e0d346ff 524 * thrown because we require this variable.
525 *
361855e6 526 * This function should be used to initialise all required values
527 * in a script that are based on parameters. Usually it will be
e0d346ff 528 * used like this:
622365d2 529 * $id = required_param('id', PARAM_INT);
e0d346ff 530 *
2ca3bffa 531 * Please note the $type parameter is now required and the value can not be array.
44913c8d
PS
532 *
533 * @param string $parname the name of the page parameter we want
534 * @param string $type expected type of parameter
e0d346ff 535 * @return mixed
ac7af0da 536 * @throws coding_exception
e0d346ff 537 */
44913c8d 538function required_param($parname, $type) {
2ca3bffa
PS
539 if (func_num_args() != 2 or empty($parname) or empty($type)) {
540 throw new coding_exception('required_param() requires $parname and $type to be specified (parameter: '.$parname.')');
44913c8d 541 }
ac7af0da
SH
542 // POST has precedence.
543 if (isset($_POST[$parname])) {
a083b93c 544 $param = $_POST[$parname];
545 } else if (isset($_GET[$parname])) {
546 $param = $_GET[$parname];
e0d346ff 547 } else {
2f137aa1 548 print_error('missingparam', '', '', $parname);
e0d346ff 549 }
550
2ca3bffa
PS
551 if (is_array($param)) {
552 debugging('Invalid array parameter detected in required_param(): '.$parname);
ac7af0da 553 // TODO: switch to fatal error in Moodle 2.3.
2ca3bffa
PS
554 return required_param_array($parname, $type);
555 }
556
a083b93c 557 return clean_param($param, $type);
e0d346ff 558}
559
2ca3bffa
PS
560/**
561 * Returns a particular array value for the named variable, taken from
562 * POST or GET. If the parameter doesn't exist then an error is
563 * thrown because we require this variable.
564 *
565 * This function should be used to initialise all required values
566 * in a script that are based on parameters. Usually it will be
567 * used like this:
568 * $ids = required_param_array('ids', PARAM_INT);
569 *
570 * Note: arrays of arrays are not supported, only alphanumeric keys with _ and - are supported
571 *
572 * @param string $parname the name of the page parameter we want
573 * @param string $type expected type of parameter
574 * @return array
ac7af0da 575 * @throws coding_exception
2ca3bffa
PS
576 */
577function required_param_array($parname, $type) {
578 if (func_num_args() != 2 or empty($parname) or empty($type)) {
579 throw new coding_exception('required_param_array() requires $parname and $type to be specified (parameter: '.$parname.')');
580 }
ac7af0da
SH
581 // POST has precedence.
582 if (isset($_POST[$parname])) {
2ca3bffa
PS
583 $param = $_POST[$parname];
584 } else if (isset($_GET[$parname])) {
585 $param = $_GET[$parname];
586 } else {
587 print_error('missingparam', '', '', $parname);
588 }
589 if (!is_array($param)) {
590 print_error('missingparam', '', '', $parname);
591 }
592
593 $result = array();
ac7af0da 594 foreach ($param as $key => $value) {
2ca3bffa
PS
595 if (!preg_match('/^[a-z0-9_-]+$/i', $key)) {
596 debugging('Invalid key name in required_param_array() detected: '.$key.', parameter: '.$parname);
597 continue;
598 }
ebdeccca 599 $result[$key] = clean_param($value, $type);
2ca3bffa
PS
600 }
601
602 return $result;
e0d346ff 603}
604
605/**
361855e6 606 * Returns a particular value for the named variable, taken from
e0d346ff 607 * POST or GET, otherwise returning a given default.
608 *
361855e6 609 * This function should be used to initialise all optional values
610 * in a script that are based on parameters. Usually it will be
e0d346ff 611 * used like this:
622365d2 612 * $name = optional_param('name', 'Fred', PARAM_TEXT);
e0d346ff 613 *
2ca3bffa 614 * Please note the $type parameter is now required and the value can not be array.
44913c8d 615 *
a083b93c 616 * @param string $parname the name of the page parameter we want
e0d346ff 617 * @param mixed $default the default value to return if nothing is found
44913c8d 618 * @param string $type expected type of parameter
e0d346ff 619 * @return mixed
ac7af0da 620 * @throws coding_exception
e0d346ff 621 */
44913c8d 622function optional_param($parname, $default, $type) {
2ca3bffa 623 if (func_num_args() != 3 or empty($parname) or empty($type)) {
ac7af0da 624 throw new coding_exception('optional_param requires $parname, $default + $type to be specified (parameter: '.$parname.')');
44913c8d
PS
625 }
626 if (!isset($default)) {
627 $default = null;
628 }
629
ac7af0da
SH
630 // POST has precedence.
631 if (isset($_POST[$parname])) {
a083b93c 632 $param = $_POST[$parname];
633 } else if (isset($_GET[$parname])) {
634 $param = $_GET[$parname];
e0d346ff 635 } else {
636 return $default;
637 }
c7f4e3e2 638
2ca3bffa
PS
639 if (is_array($param)) {
640 debugging('Invalid array parameter detected in required_param(): '.$parname);
ac7af0da 641 // TODO: switch to $default in Moodle 2.3.
2ca3bffa
PS
642 return optional_param_array($parname, $default, $type);
643 }
644
a083b93c 645 return clean_param($param, $type);
e0d346ff 646}
647
2ca3bffa
PS
648/**
649 * Returns a particular array value for the named variable, taken from
650 * POST or GET, otherwise returning a given default.
651 *
652 * This function should be used to initialise all optional values
653 * in a script that are based on parameters. Usually it will be
654 * used like this:
655 * $ids = optional_param('id', array(), PARAM_INT);
656 *
ac7af0da 657 * Note: arrays of arrays are not supported, only alphanumeric keys with _ and - are supported
2ca3bffa
PS
658 *
659 * @param string $parname the name of the page parameter we want
ac7af0da 660 * @param mixed $default the default value to return if nothing is found
2ca3bffa
PS
661 * @param string $type expected type of parameter
662 * @return array
ac7af0da 663 * @throws coding_exception
2ca3bffa
PS
664 */
665function optional_param_array($parname, $default, $type) {
666 if (func_num_args() != 3 or empty($parname) or empty($type)) {
ac7af0da 667 throw new coding_exception('optional_param_array requires $parname, $default + $type to be specified (parameter: '.$parname.')');
2ca3bffa
PS
668 }
669
ac7af0da
SH
670 // POST has precedence.
671 if (isset($_POST[$parname])) {
2ca3bffa
PS
672 $param = $_POST[$parname];
673 } else if (isset($_GET[$parname])) {
674 $param = $_GET[$parname];
675 } else {
676 return $default;
677 }
678 if (!is_array($param)) {
679 debugging('optional_param_array() expects array parameters only: '.$parname);
680 return $default;
681 }
682
683 $result = array();
ac7af0da 684 foreach ($param as $key => $value) {
2ca3bffa
PS
685 if (!preg_match('/^[a-z0-9_-]+$/i', $key)) {
686 debugging('Invalid key name in optional_param_array() detected: '.$key.', parameter: '.$parname);
687 continue;
688 }
ebdeccca 689 $result[$key] = clean_param($value, $type);
2ca3bffa
PS
690 }
691
692 return $result;
e0d346ff 693}
694
a3f7cbf6 695/**
696 * Strict validation of parameter values, the values are only converted
697 * to requested PHP type. Internally it is using clean_param, the values
698 * before and after cleaning must be equal - otherwise
699 * an invalid_parameter_exception is thrown.
efb8c375 700 * Objects and classes are not accepted.
a3f7cbf6 701 *
702 * @param mixed $param
2ca3bffa 703 * @param string $type PARAM_ constant
a3f7cbf6 704 * @param bool $allownull are nulls valid value?
705 * @param string $debuginfo optional debug information
fea52c11
PS
706 * @return mixed the $param value converted to PHP type
707 * @throws invalid_parameter_exception if $param is not of given type
a3f7cbf6 708 */
5a1861ee 709function validate_param($param, $type, $allownull=NULL_NOT_ALLOWED, $debuginfo='') {
a3f7cbf6 710 if (is_null($param)) {
5a1861ee 711 if ($allownull == NULL_ALLOWED) {
a3f7cbf6 712 return null;
713 } else {
714 throw new invalid_parameter_exception($debuginfo);
715 }
716 }
717 if (is_array($param) or is_object($param)) {
718 throw new invalid_parameter_exception($debuginfo);
719 }
720
721 $cleaned = clean_param($param, $type);
fea52c11
PS
722
723 if ($type == PARAM_FLOAT) {
724 // Do not detect precision loss here.
725 if (is_float($param) or is_int($param)) {
726 // These always fit.
727 } else if (!is_numeric($param) or !preg_match('/^[\+-]?[0-9]*\.?[0-9]*(e[-+]?[0-9]+)?$/i', (string)$param)) {
728 throw new invalid_parameter_exception($debuginfo);
729 }
730 } else if ((string)$param !== (string)$cleaned) {
ac7af0da 731 // Conversion to string is usually lossless.
a3f7cbf6 732 throw new invalid_parameter_exception($debuginfo);
733 }
734
735 return $cleaned;
736}
737
2ca3bffa 738/**
ac7af0da
SH
739 * Makes sure array contains only the allowed types, this function does not validate array key names!
740 *
2ca3bffa
PS
741 * <code>
742 * $options = clean_param($options, PARAM_INT);
743 * </code>
744 *
745 * @param array $param the variable array we are cleaning
746 * @param string $type expected format of param after cleaning.
747 * @param bool $recursive clean recursive arrays
748 * @return array
ac7af0da 749 * @throws coding_exception
2ca3bffa
PS
750 */
751function clean_param_array(array $param = null, $type, $recursive = false) {
ac7af0da
SH
752 // Convert null to empty array.
753 $param = (array)$param;
2ca3bffa
PS
754 foreach ($param as $key => $value) {
755 if (is_array($value)) {
756 if ($recursive) {
757 $param[$key] = clean_param_array($value, $type, true);
758 } else {
ac7af0da 759 throw new coding_exception('clean_param_array can not process multidimensional arrays when $recursive is false.');
2ca3bffa
PS
760 }
761 } else {
762 $param[$key] = clean_param($value, $type);
763 }
764 }
765 return $param;
766}
767
e0d346ff 768/**
361855e6 769 * Used by {@link optional_param()} and {@link required_param()} to
770 * clean the variables and/or cast to specific types, based on
e0d346ff 771 * an options field.
bbd3f2c4 772 * <code>
773 * $course->format = clean_param($course->format, PARAM_ALPHA);
ac7af0da 774 * $selectedgradeitem = clean_param($selectedgradeitem, PARAM_INT);
bbd3f2c4 775 * </code>
e0d346ff 776 *
777 * @param mixed $param the variable we are cleaning
2ca3bffa 778 * @param string $type expected format of param after cleaning.
e0d346ff 779 * @return mixed
ac7af0da 780 * @throws coding_exception
e0d346ff 781 */
a083b93c 782function clean_param($param, $type) {
7744ea12 783 global $CFG;
c7f4e3e2 784
c16c1be7
PS
785 if (is_array($param)) {
786 throw new coding_exception('clean_param() can not process arrays, please use clean_param_array() instead.');
787 } else if (is_object($param)) {
788 if (method_exists($param, '__toString')) {
789 $param = $param->__toString();
790 } else {
791 throw new coding_exception('clean_param() can not process objects, please use clean_param_array() instead.');
792 }
80bfd470 793 }
794
a083b93c 795 switch ($type) {
ac7af0da
SH
796 case PARAM_RAW:
797 // No cleaning at all.
78fcdb5f 798 $param = fix_utf8($param);
96e98ea6 799 return $param;
800
ac7af0da
SH
801 case PARAM_RAW_TRIMMED:
802 // No cleaning, but strip leading and trailing whitespace.
78fcdb5f 803 $param = fix_utf8($param);
652599ec
TH
804 return trim($param);
805
ac7af0da
SH
806 case PARAM_CLEAN:
807 // General HTML cleaning, try to use more specific type if possible this is deprecated!
808 // Please use more specific type instead.
a083b93c 809 if (is_numeric($param)) {
810 return $param;
811 }
78fcdb5f 812 $param = fix_utf8($param);
ac7af0da
SH
813 // Sweep for scripts, etc.
814 return clean_text($param);
3af57507 815
ac7af0da
SH
816 case PARAM_CLEANHTML:
817 // Clean html fragment.
78fcdb5f 818 $param = fix_utf8($param);
ac7af0da
SH
819 // Sweep for scripts, etc.
820 $param = clean_text($param, FORMAT_HTML);
a083b93c 821 return trim($param);
e0d346ff 822
a083b93c 823 case PARAM_INT:
ac7af0da
SH
824 // Convert to integer.
825 return (int)$param;
e0d346ff 826
6e73ae10 827 case PARAM_FLOAT:
ac7af0da
SH
828 // Convert to float.
829 return (float)$param;
9dae915a 830
ac7af0da
SH
831 case PARAM_ALPHA:
832 // Remove everything not `a-z`.
6dbcacee 833 return preg_replace('/[^a-zA-Z]/i', '', $param);
e0d346ff 834
ac7af0da
SH
835 case PARAM_ALPHAEXT:
836 // Remove everything not `a-zA-Z_-` (originally allowed "/" too).
6dbcacee 837 return preg_replace('/[^a-zA-Z_-]/i', '', $param);
6e73ae10 838
ac7af0da
SH
839 case PARAM_ALPHANUM:
840 // Remove everything not `a-zA-Z0-9`.
6dbcacee 841 return preg_replace('/[^A-Za-z0-9]/i', '', $param);
f24148ef 842
ac7af0da
SH
843 case PARAM_ALPHANUMEXT:
844 // Remove everything not `a-zA-Z0-9_-`.
6dbcacee 845 return preg_replace('/[^A-Za-z0-9_-]/i', '', $param);
0ed442f8 846
ac7af0da
SH
847 case PARAM_SEQUENCE:
848 // Remove everything not `0-9,`.
6dbcacee 849 return preg_replace('/[^0-9,]/i', '', $param);
0e4af166 850
ac7af0da
SH
851 case PARAM_BOOL:
852 // Convert to 1 or 0.
a083b93c 853 $tempstr = strtolower($param);
6e73ae10 854 if ($tempstr === 'on' or $tempstr === 'yes' or $tempstr === 'true') {
a083b93c 855 $param = 1;
6e73ae10 856 } else if ($tempstr === 'off' or $tempstr === 'no' or $tempstr === 'false') {
a083b93c 857 $param = 0;
858 } else {
859 $param = empty($param) ? 0 : 1;
860 }
861 return $param;
f24148ef 862
ac7af0da
SH
863 case PARAM_NOTAGS:
864 // Strip all tags.
78fcdb5f 865 $param = fix_utf8($param);
a083b93c 866 return strip_tags($param);
3af57507 867
ac7af0da
SH
868 case PARAM_TEXT:
869 // Leave only tags needed for multilang.
78fcdb5f 870 $param = fix_utf8($param);
ac7af0da
SH
871 // If the multilang syntax is not correct we strip all tags because it would break xhtml strict which is required
872 // for accessibility standards please note this cleaning does not strip unbalanced '>' for BC compatibility reasons.
b6059edc
PS
873 do {
874 if (strpos($param, '</lang>') !== false) {
ac7af0da 875 // Old and future mutilang syntax.
b6059edc
PS
876 $param = strip_tags($param, '<lang>');
877 if (!preg_match_all('/<.*>/suU', $param, $matches)) {
878 break;
879 }
880 $open = false;
881 foreach ($matches[0] as $match) {
882 if ($match === '</lang>') {
883 if ($open) {
884 $open = false;
885 continue;
886 } else {
887 break 2;
888 }
889 }
890 if (!preg_match('/^<lang lang="[a-zA-Z0-9_-]+"\s*>$/u', $match)) {
891 break 2;
892 } else {
893 $open = true;
894 }
895 }
896 if ($open) {
897 break;
898 }
899 return $param;
900
901 } else if (strpos($param, '</span>') !== false) {
ac7af0da 902 // Current problematic multilang syntax.
b6059edc
PS
903 $param = strip_tags($param, '<span>');
904 if (!preg_match_all('/<.*>/suU', $param, $matches)) {
905 break;
906 }
907 $open = false;
908 foreach ($matches[0] as $match) {
909 if ($match === '</span>') {
910 if ($open) {
911 $open = false;
912 continue;
913 } else {
914 break 2;
915 }
916 }
917 if (!preg_match('/^<span(\s+lang="[a-zA-Z0-9_-]+"|\s+class="multilang"){2}\s*>$/u', $match)) {
918 break 2;
919 } else {
920 $open = true;
921 }
922 }
923 if ($open) {
924 break;
925 }
926 return $param;
927 }
928 } while (false);
ac7af0da 929 // Easy, just strip all tags, if we ever want to fix orphaned '&' we have to do that in format_string().
b6059edc 930 return strip_tags($param);
31f26796 931
aff24313 932 case PARAM_COMPONENT:
ac7af0da
SH
933 // We do not want any guessing here, either the name is correct or not
934 // please note only normalised component names are accepted.
a41d1ca0 935 if (!preg_match('/^[a-z]+(_[a-z][a-z0-9_]*)?[a-z0-9]+$/', $param)) {
aff24313
PS
936 return '';
937 }
938 if (strpos($param, '__') !== false) {
939 return '';
940 }
941 if (strpos($param, 'mod_') === 0) {
ac7af0da 942 // Module names must not contain underscores because we need to differentiate them from invalid plugin types.
aff24313
PS
943 if (substr_count($param, '_') != 1) {
944 return '';
945 }
946 }
947 return $param;
948
949 case PARAM_PLUGIN:
950 case PARAM_AREA:
ac7af0da 951 // We do not want any guessing here, either the name is correct or not.
5f850735 952 if (!is_valid_plugin_name($param)) {
aff24313
PS
953 return '';
954 }
955 return $param;
956
ac7af0da
SH
957 case PARAM_SAFEDIR:
958 // Remove everything not a-zA-Z0-9_- .
6dbcacee 959 return preg_replace('/[^a-zA-Z0-9_-]/i', '', $param);
95bfd207 960
ac7af0da
SH
961 case PARAM_SAFEPATH:
962 // Remove everything not a-zA-Z0-9/_- .
6759ad2f 963 return preg_replace('/[^a-zA-Z0-9\/_-]/i', '', $param);
6e73ae10 964
ac7af0da
SH
965 case PARAM_FILE:
966 // Strip all suspicious characters from filename.
78fcdb5f 967 $param = fix_utf8($param);
14f3ad15 968 $param = preg_replace('~[[:cntrl:]]|[&<>"`\|\':\\\\/]~u', '', $param);
caf16a57 969 if ($param === '.' || $param === '..') {
371a2ed0 970 $param = '';
971 }
a083b93c 972 return $param;
973
ac7af0da
SH
974 case PARAM_PATH:
975 // Strip all suspicious characters from file path.
78fcdb5f 976 $param = fix_utf8($param);
a083b93c 977 $param = str_replace('\\', '/', $param);
caf16a57
FM
978
979 // Explode the path and clean each element using the PARAM_FILE rules.
980 $breadcrumb = explode('/', $param);
981 foreach ($breadcrumb as $key => $crumb) {
982 if ($crumb === '.' && $key === 0) {
983 // Special condition to allow for relative current path such as ./currentdirfile.txt.
984 } else {
985 $crumb = clean_param($crumb, PARAM_FILE);
986 }
987 $breadcrumb[$key] = $crumb;
988 }
989 $param = implode('/', $breadcrumb);
990
991 // Remove multiple current path (./././) and multiple slashes (///).
6dbcacee 992 $param = preg_replace('~//+~', '/', $param);
caf16a57
FM
993 $param = preg_replace('~/(\./)+~', '/', $param);
994 return $param;
a083b93c 995
ac7af0da
SH
996 case PARAM_HOST:
997 // Allow FQDN or IPv4 dotted quad.
998 $param = preg_replace('/[^\.\d\w-]/', '', $param );
999 // Match ipv4 dotted quad.
1000 if (preg_match('/(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})/', $param, $match)) {
1001 // Confirm values are ok.
a083b93c 1002 if ( $match[0] > 255
1003 || $match[1] > 255
1004 || $match[3] > 255
1005 || $match[4] > 255 ) {
ac7af0da 1006 // Hmmm, what kind of dotted quad is this?
a083b93c 1007 $param = '';
1008 }
ac7af0da
SH
1009 } else if ( preg_match('/^[\w\d\.-]+$/', $param) // Dots, hyphens, numbers.
1010 && !preg_match('/^[\.-]/', $param) // No leading dots/hyphens.
1011 && !preg_match('/[\.-]$/', $param) // No trailing dots/hyphens.
a083b93c 1012 ) {
ac7af0da 1013 // All is ok - $param is respected.
a083b93c 1014 } else {
ac7af0da 1015 // All is not ok...
a083b93c 1016 $param='';
1017 }
1018 return $param;
7744ea12 1019
ac7af0da 1020 case PARAM_URL: // Allow safe ftp, http, mailto urls.
78fcdb5f 1021 $param = fix_utf8($param);
a083b93c 1022 include_once($CFG->dirroot . '/lib/validateurlsyntax.php');
5301205a 1023 if (!empty($param) && validateUrlSyntax($param, 's?H?S?F?E?u-P-a?I?p?f?q?r?')) {
ac7af0da 1024 // All is ok, param is respected.
d2a9f7cc 1025 } else {
ac7af0da
SH
1026 // Not really ok.
1027 $param ='';
a083b93c 1028 }
1029 return $param;
1030
ac7af0da
SH
1031 case PARAM_LOCALURL:
1032 // Allow http absolute, root relative and relative URLs within wwwroot.
93684765 1033 $param = clean_param($param, PARAM_URL);
a083b93c 1034 if (!empty($param)) {
1035 if (preg_match(':^/:', $param)) {
ac7af0da
SH
1036 // Root-relative, ok!
1037 } else if (preg_match('/^'.preg_quote($CFG->wwwroot, '/').'/i', $param)) {
1038 // Absolute, and matches our wwwroot.
7744ea12 1039 } else {
ac7af0da 1040 // Relative - let's make sure there are no tricks.
4bea5e85 1041 if (validateUrlSyntax('/' . $param, 's-u-P-a-p-f+q?r?')) {
ac7af0da 1042 // Looks ok.
a083b93c 1043 } else {
1044 $param = '';
1045 }
d2a9f7cc 1046 }
7744ea12 1047 }
a083b93c 1048 return $param;
bcef0319 1049
03d820c7 1050 case PARAM_PEM:
1051 $param = trim($param);
ac7af0da
SH
1052 // PEM formatted strings may contain letters/numbers and the symbols:
1053 // forward slash: /
1054 // plus sign: +
1055 // equal sign: =
1056 // , surrounded by BEGIN and END CERTIFICATE prefix and suffixes.
03d820c7 1057 if (preg_match('/^-----BEGIN CERTIFICATE-----([\s\w\/\+=]+)-----END CERTIFICATE-----$/', trim($param), $matches)) {
1058 list($wholething, $body) = $matches;
1059 unset($wholething, $matches);
1060 $b64 = clean_param($body, PARAM_BASE64);
1061 if (!empty($b64)) {
1062 return "-----BEGIN CERTIFICATE-----\n$b64\n-----END CERTIFICATE-----\n";
1063 } else {
1064 return '';
1065 }
1066 }
1067 return '';
bcef0319 1068
03d820c7 1069 case PARAM_BASE64:
1070 if (!empty($param)) {
1071 // PEM formatted strings may contain letters/numbers and the symbols
ac7af0da
SH
1072 // forward slash: /
1073 // plus sign: +
1074 // equal sign: =.
03d820c7 1075 if (0 >= preg_match('/^([\s\w\/\+=]+)$/', trim($param))) {
1076 return '';
1077 }
1078 $lines = preg_split('/[\s]+/', $param, -1, PREG_SPLIT_NO_EMPTY);
ac7af0da
SH
1079 // Each line of base64 encoded data must be 64 characters in length, except for the last line which may be less
1080 // than (or equal to) 64 characters long.
03d820c7 1081 for ($i=0, $j=count($lines); $i < $j; $i++) {
1082 if ($i + 1 == $j) {
1083 if (64 < strlen($lines[$i])) {
1084 return '';
1085 }
1086 continue;
1087 }
7744ea12 1088
03d820c7 1089 if (64 != strlen($lines[$i])) {
1090 return '';
1091 }
1092 }
ac7af0da 1093 return implode("\n", $lines);
03d820c7 1094 } else {
1095 return '';
1096 }
bcef0319 1097
1098 case PARAM_TAG:
78fcdb5f 1099 $param = fix_utf8($param);
34b93e39
PS
1100 // Please note it is not safe to use the tag name directly anywhere,
1101 // it must be processed with s(), urlencode() before embedding anywhere.
ac7af0da 1102 // Remove some nasties.
6b24e35e 1103 $param = preg_replace('~[[:cntrl:]]|[<>`]~u', '', $param);
ac7af0da 1104 // Convert many whitespace chars into one.
bcef0319 1105 $param = preg_replace('/\s+/', ' ', $param);
2f1e464a 1106 $param = core_text::substr(trim($param), 0, TAG_MAX_LENGTH);
c93c6b3b 1107 return $param;
bcef0319 1108
ae040d4b 1109 case PARAM_TAGLIST:
78fcdb5f 1110 $param = fix_utf8($param);
ae040d4b 1111 $tags = explode(',', $param);
1112 $result = array();
1113 foreach ($tags as $tag) {
1114 $res = clean_param($tag, PARAM_TAG);
6e73ae10 1115 if ($res !== '') {
ae040d4b 1116 $result[] = $res;
1117 }
1118 }
1119 if ($result) {
1120 return implode(',', $result);
1121 } else {
1122 return '';
0d626493 1123 }
1124
ad944e78 1125 case PARAM_CAPABILITY:
4f0c2d00 1126 if (get_capability_info($param)) {
ad944e78 1127 return $param;
1128 } else {
1129 return '';
1130 }
1131
faf75fe7 1132 case PARAM_PERMISSION:
1133 $param = (int)$param;
1134 if (in_array($param, array(CAP_INHERIT, CAP_ALLOW, CAP_PREVENT, CAP_PROHIBIT))) {
1135 return $param;
1136 } else {
1137 return CAP_INHERIT;
1138 }
1139
03b31ea3 1140 case PARAM_AUTH:
aff24313
PS
1141 $param = clean_param($param, PARAM_PLUGIN);
1142 if (empty($param)) {
1143 return '';
1144 } else if (exists_auth_plugin($param)) {
03b31ea3 1145 return $param;
1146 } else {
1147 return '';
1148 }
1149
1150 case PARAM_LANG:
1151 $param = clean_param($param, PARAM_SAFEDIR);
ef686eb5 1152 if (get_string_manager()->translation_exists($param)) {
03b31ea3 1153 return $param;
1154 } else {
ac7af0da
SH
1155 // Specified language is not installed or param malformed.
1156 return '';
03b31ea3 1157 }
1158
1159 case PARAM_THEME:
aff24313
PS
1160 $param = clean_param($param, PARAM_PLUGIN);
1161 if (empty($param)) {
1162 return '';
1163 } else if (file_exists("$CFG->dirroot/theme/$param/config.php")) {
73e504bc
PS
1164 return $param;
1165 } else if (!empty($CFG->themedir) and file_exists("$CFG->themedir/$param/config.php")) {
03b31ea3 1166 return $param;
1167 } else {
ac7af0da
SH
1168 // Specified theme is not installed.
1169 return '';
03b31ea3 1170 }
1171
07ed083e 1172 case PARAM_USERNAME:
78fcdb5f 1173 $param = fix_utf8($param);
07ed083e 1174 $param = str_replace(" " , "", $param);
ac7af0da 1175 // Convert uppercase to lowercase MDL-16919.
2f1e464a 1176 $param = core_text::strtolower($param);
34d2b19a 1177 if (empty($CFG->extendedusernamechars)) {
ac7af0da 1178 // Regular expression, eliminate all chars EXCEPT:
07ed083e
RW
1179 // alphanum, dash (-), underscore (_), at sign (@) and period (.) characters.
1180 $param = preg_replace('/[^-\.@_a-z0-9]/', '', $param);
4f0c2d00 1181 }
07ed083e
RW
1182 return $param;
1183
79f1d953 1184 case PARAM_EMAIL:
78fcdb5f 1185 $param = fix_utf8($param);
79f1d953 1186 if (validate_email($param)) {
1187 return $param;
1188 } else {
1189 return '';
1190 }
1191
fe6a248f
DM
1192 case PARAM_STRINGID:
1193 if (preg_match('|^[a-zA-Z][a-zA-Z0-9\.:/_-]*$|', $param)) {
1194 return $param;
1195 } else {
1196 return '';
1197 }
1198
ac7af0da
SH
1199 case PARAM_TIMEZONE:
1200 // Can be int, float(with .5 or .0) or string seperated by '/' and can have '-_'.
78fcdb5f 1201 $param = fix_utf8($param);
8158ce79 1202 $timezonepattern = '/^(([+-]?(0?[0-9](\.[5|0])?|1[0-3](\.0)?|1[0-2]\.5))|(99)|[[:alnum:]]+(\/?[[:alpha:]_-])+)$/';
ccc77f91
RT
1203 if (preg_match($timezonepattern, $param)) {
1204 return $param;
1205 } else {
1206 return '';
1207 }
1208
ac7af0da
SH
1209 default:
1210 // Doh! throw error, switched parameters in optional_param or another serious problem.
03b31ea3 1211 print_error("unknownparamtype", '', '', $type);
2ae28153 1212 }
e0d346ff 1213}
1214
78fcdb5f
PS
1215/**
1216 * Makes sure the data is using valid utf8, invalid characters are discarded.
1217 *
1218 * Note: this function is not intended for full objects with methods and private properties.
1219 *
1220 * @param mixed $value
1221 * @return mixed with proper utf-8 encoding
1222 */
1223function fix_utf8($value) {
1224 if (is_null($value) or $value === '') {
1225 return $value;
1226
1227 } else if (is_string($value)) {
1228 if ((string)(int)$value === $value) {
ac7af0da 1229 // Shortcut.
78fcdb5f
PS
1230 return $value;
1231 }
bff1d60c
PS
1232 // No null bytes expected in our data, so let's remove it.
1233 $value = str_replace("\0", '', $value);
0aff15c2 1234
0aff15c2
PS
1235 // Note: this duplicates min_fix_utf8() intentionally.
1236 static $buggyiconv = null;
1237 if ($buggyiconv === null) {
dd47f210 1238 $buggyiconv = (!function_exists('iconv') or @iconv('UTF-8', 'UTF-8//IGNORE', '100'.chr(130).'€') !== '100€');
0aff15c2
PS
1239 }
1240
1241 if ($buggyiconv) {
1242 if (function_exists('mb_convert_encoding')) {
1243 $subst = mb_substitute_character();
1244 mb_substitute_character('');
1245 $result = mb_convert_encoding($value, 'utf-8', 'utf-8');
1246 mb_substitute_character($subst);
1247
1248 } else {
1249 // Warn admins on admin/index.php page.
1250 $result = $value;
1251 }
1252
1253 } else {
dd47f210 1254 $result = @iconv('UTF-8', 'UTF-8//IGNORE', $value);
51b7297b 1255 }
0aff15c2 1256
51b7297b 1257 return $result;
78fcdb5f
PS
1258
1259 } else if (is_array($value)) {
ac7af0da 1260 foreach ($value as $k => $v) {
78fcdb5f
PS
1261 $value[$k] = fix_utf8($v);
1262 }
1263 return $value;
1264
1265 } else if (is_object($value)) {
ac7af0da
SH
1266 // Do not modify original.
1267 $value = clone($value);
1268 foreach ($value as $k => $v) {
78fcdb5f
PS
1269 $value->$k = fix_utf8($v);
1270 }
1271 return $value;
1272
1273 } else {
ac7af0da 1274 // This is some other type, no utf-8 here.
78fcdb5f
PS
1275 return $value;
1276 }
1277}
1278
6e73ae10 1279/**
1280 * Return true if given value is integer or string with integer value
0d0a8bf6 1281 *
1282 * @param mixed $value String or Int
1283 * @return bool true if number, false if not
6e73ae10 1284 */
1285function is_number($value) {
1286 if (is_int($value)) {
1287 return true;
1288 } else if (is_string($value)) {
1289 return ((string)(int)$value) === $value;
1290 } else {
1291 return false;
1292 }
1293}
7a530277 1294
aa282b10 1295/**
ac7af0da
SH
1296 * Returns host part from url.
1297 *
aa282b10 1298 * @param string $url full url
1299 * @return string host, null if not found
1300 */
1301function get_host_from_url($url) {
1302 preg_match('|^[a-z]+://([a-zA-Z0-9-.]+)|i', $url, $matches);
1303 if ($matches) {
1304 return $matches[1];
1305 }
1306 return null;
1307}
1308
94a6d656 1309/**
0d0a8bf6 1310 * Tests whether anything was returned by text editor
1311 *
94a6d656 1312 * This function is useful for testing whether something you got back from
1313 * the HTML editor actually contains anything. Sometimes the HTML editor
1314 * appear to be empty, but actually you get back a <br> tag or something.
1315 *
1316 * @param string $string a string containing HTML.
1317 * @return boolean does the string contain any actual content - that is text,
efb8c375 1318 * images, objects, etc.
94a6d656 1319 */
1320function html_is_blank($string) {
1321 return trim(strip_tags($string, '<img><object><applet><input><select><textarea><hr>')) == '';
1322}
1323
7cf1c7bd 1324/**
1325 * Set a key in global configuration
1326 *
89dcb99d 1327 * Set a key/value pair in both this session's {@link $CFG} global variable
7cf1c7bd 1328 * and in the 'config' database table for future sessions.
e1ecf0a0 1329 *
1330 * Can also be used to update keys for plugin-scoped configs in config_plugin table.
1331 * In that case it doesn't affect $CFG.
7cf1c7bd 1332 *
6fd511eb 1333 * A NULL value will delete the entry.
1334 *
08b51dd0
JO
1335 * NOTE: this function is called from lib/db/upgrade.php
1336 *
7cf1c7bd 1337 * @param string $name the key to set
9cdb766d 1338 * @param string $value the value to set (without magic quotes)
ac7af0da 1339 * @param string $plugin (optional) the plugin scope, default null
5e2f308b 1340 * @return bool true or exception
7cf1c7bd 1341 */
ac7af0da 1342function set_config($name, $value, $plugin=null) {
ae040d4b 1343 global $CFG, $DB;
42282810 1344
a4080313 1345 if (empty($plugin)) {
220a90c5 1346 if (!array_key_exists($name, $CFG->config_php_settings)) {
ac7af0da 1347 // So it's defined for this invocation at least.
220a90c5 1348 if (is_null($value)) {
1349 unset($CFG->$name);
1350 } else {
ac7af0da
SH
1351 // Settings from db are always strings.
1352 $CFG->$name = (string)$value;
220a90c5 1353 }
1354 }
e1ecf0a0 1355
ac7af0da 1356 if ($DB->get_field('config', 'name', array('name' => $name))) {
5e2f308b 1357 if ($value === null) {
ac7af0da 1358 $DB->delete_records('config', array('name' => $name));
6fd511eb 1359 } else {
ac7af0da 1360 $DB->set_field('config', 'value', $value, array('name' => $name));
6fd511eb 1361 }
a4080313 1362 } else {
5e2f308b 1363 if ($value !== null) {
365a5941 1364 $config = new stdClass();
5e2f308b 1365 $config->name = $name;
1366 $config->value = $value;
1367 $DB->insert_record('config', $config, false);
6fd511eb 1368 }
a4080313 1369 }
e0d9b7c0
SH
1370 if ($name === 'siteidentifier') {
1371 cache_helper::update_site_identifier($value);
1372 }
007bfe8b 1373 cache_helper::invalidate_by_definition('core', 'config', array(), 'core');
ac7af0da
SH
1374 } else {
1375 // Plugin scope.
1376 if ($id = $DB->get_field('config_plugins', 'id', array('name' => $name, 'plugin' => $plugin))) {
6fd511eb 1377 if ($value===null) {
ac7af0da 1378 $DB->delete_records('config_plugins', array('name' => $name, 'plugin' => $plugin));
6fd511eb 1379 } else {
ac7af0da 1380 $DB->set_field('config_plugins', 'value', $value, array('id' => $id));
6fd511eb 1381 }
a4080313 1382 } else {
5e2f308b 1383 if ($value !== null) {
365a5941 1384 $config = new stdClass();
5e2f308b 1385 $config->plugin = $plugin;
1386 $config->name = $name;
1387 $config->value = $value;
1388 $DB->insert_record('config_plugins', $config, false);
6fd511eb 1389 }
a4080313 1390 }
007bfe8b 1391 cache_helper::invalidate_by_definition('core', 'config', array(), $plugin);
a4080313 1392 }
5e2f308b 1393
1394 return true;
a4080313 1395}
1396
1397/**
e1ecf0a0 1398 * Get configuration values from the global config table
a4080313 1399 * or the config_plugins table.
1400 *
13daf6a2 1401 * If called with one parameter, it will load all the config
12bb0c3e 1402 * variables for one plugin, and return them as an object.
13daf6a2 1403 *
12bb0c3e
PS
1404 * If called with 2 parameters it will return a string single
1405 * value or false if the value is not found.
9220fba5 1406 *
08b51dd0
JO
1407 * NOTE: this function is called from lib/db/upgrade.php
1408 *
ac7af0da 1409 * @static string|false $siteidentifier The site identifier is not cached. We use this static cache so
e0d9b7c0 1410 * that we need only fetch it once per request.
12bb0c3e 1411 * @param string $plugin full component name
ac7af0da 1412 * @param string $name default null
07ab0c80 1413 * @return mixed hash-like object or single value, return false no config found
ac7af0da 1414 * @throws dml_exception
a4080313 1415 */
ac7af0da 1416function get_config($plugin, $name = null) {
ae040d4b 1417 global $CFG, $DB;
dfc9ba9b 1418
e0d9b7c0
SH
1419 static $siteidentifier = null;
1420
007bfe8b
SH
1421 if ($plugin === 'moodle' || $plugin === 'core' || empty($plugin)) {
1422 $forced =& $CFG->config_php_settings;
1423 $iscore = true;
1424 $plugin = 'core';
1425 } else {
1426 if (array_key_exists($plugin, $CFG->forced_plugin_settings)) {
1427 $forced =& $CFG->forced_plugin_settings[$plugin];
1428 } else {
1429 $forced = array();
1430 }
1431 $iscore = false;
12bb0c3e
PS
1432 }
1433
e0d9b7c0
SH
1434 if ($siteidentifier === null) {
1435 try {
1436 // This may fail during installation.
1437 // If you have a look at {@link initialise_cfg()} you will see that this is how we detect the need to
1438 // install the database.
1439 $siteidentifier = $DB->get_field('config', 'value', array('name' => 'siteidentifier'));
1440 } catch (dml_exception $ex) {
e0d9b7c0
SH
1441 // Set siteidentifier to false. We don't want to trip this continually.
1442 $siteidentifier = false;
1443 throw $ex;
1444 }
1445 }
1446
1447 if (!empty($name)) {
1448 if (array_key_exists($name, $forced)) {
1449 return (string)$forced[$name];
1450 } else if ($name === 'siteidentifier' && $plugin == 'core') {
1451 return $siteidentifier;
1452 }
007bfe8b
SH
1453 }
1454
1455 $cache = cache::make('core', 'config');
1456 $result = $cache->get($plugin);
d0749719 1457 if ($result === false) {
ac7af0da 1458 // The user is after a recordset.
007bfe8b 1459 if (!$iscore) {
ac7af0da 1460 $result = $DB->get_records_menu('config_plugins', array('plugin' => $plugin), '', 'name,value');
a4080313 1461 } else {
ac7af0da 1462 // This part is not really used any more, but anyway...
007bfe8b 1463 $result = $DB->get_records_menu('config', array(), '', 'name,value');;
a4080313 1464 }
007bfe8b 1465 $cache->set($plugin, $result);
a4080313 1466 }
1467
007bfe8b
SH
1468 if (!empty($name)) {
1469 if (array_key_exists($name, $result)) {
1470 return $result[$name];
bfb82da3 1471 }
007bfe8b
SH
1472 return false;
1473 }
e1ecf0a0 1474
e0d9b7c0
SH
1475 if ($plugin === 'core') {
1476 $result['siteidentifier'] = $siteidentifier;
1477 }
1478
007bfe8b
SH
1479 foreach ($forced as $key => $value) {
1480 if (is_null($value) or is_array($value) or is_object($value)) {
ac7af0da 1481 // We do not want any extra mess here, just real settings that could be saved in db.
007bfe8b
SH
1482 unset($result[$key]);
1483 } else {
ac7af0da 1484 // Convert to string as if it went through the DB.
007bfe8b 1485 $result[$key] = (string)$value;
12bb0c3e 1486 }
39917a09 1487 }
007bfe8b
SH
1488
1489 return (object)$result;
39917a09 1490}
1491
b0270f84 1492/**
ac7af0da 1493 * Removes a key from global configuration.
b0270f84 1494 *
08b51dd0
JO
1495 * NOTE: this function is called from lib/db/upgrade.php
1496 *
b0270f84 1497 * @param string $name the key to set
1498 * @param string $plugin (optional) the plugin scope
4b600aa0 1499 * @return boolean whether the operation succeeded.
b0270f84 1500 */
ac7af0da 1501function unset_config($name, $plugin=null) {
ae040d4b 1502 global $CFG, $DB;
b0270f84 1503
b0270f84 1504 if (empty($plugin)) {
4b600aa0 1505 unset($CFG->$name);
ac7af0da 1506 $DB->delete_records('config', array('name' => $name));
007bfe8b 1507 cache_helper::invalidate_by_definition('core', 'config', array(), 'core');
5e623a33 1508 } else {
ac7af0da 1509 $DB->delete_records('config_plugins', array('name' => $name, 'plugin' => $plugin));
007bfe8b 1510 cache_helper::invalidate_by_definition('core', 'config', array(), $plugin);
b0270f84 1511 }
013376de 1512
1513 return true;
b0270f84 1514}
1515
4b600aa0 1516/**
1517 * Remove all the config variables for a given plugin.
ac7af0da 1518 *
c2ca2d8e 1519 * NOTE: this function is called from lib/db/upgrade.php
4b600aa0 1520 *
1521 * @param string $plugin a plugin, for example 'quiz' or 'qtype_multichoice';
1522 * @return boolean whether the operation succeeded.
1523 */
1524function unset_all_config_for_plugin($plugin) {
1525 global $DB;
ac7af0da 1526 // Delete from the obvious config_plugins first.
013376de 1527 $DB->delete_records('config_plugins', array('plugin' => $plugin));
ac7af0da 1528 // Next delete any suspect settings from config.
a4193166
PS
1529 $like = $DB->sql_like('name', '?', true, true, false, '|');
1530 $params = array($DB->sql_like_escape($plugin.'_', '|') . '%');
1531 $DB->delete_records_select('config', $like, $params);
007bfe8b
SH
1532 // Finally clear both the plugin cache and the core cache (suspect settings now removed from core).
1533 cache_helper::invalidate_by_definition('core', 'config', array(), array('core', $plugin));
1534
013376de 1535 return true;
4b600aa0 1536}
1537
4413941f 1538/**
efb8c375 1539 * Use this function to get a list of users from a config setting of type admin_setting_users_with_capability.
adf176d7
PS
1540 *
1541 * All users are verified if they still have the necessary capability.
1542 *
b3d960e6 1543 * @param string $value the value of the config setting.
4413941f 1544 * @param string $capability the capability - must match the one passed to the admin_setting_users_with_capability constructor.
ac7af0da 1545 * @param bool $includeadmins include administrators.
4413941f 1546 * @return array of user objects.
1547 */
adf176d7 1548function get_users_from_config($value, $capability, $includeadmins = true) {
adf176d7
PS
1549 if (empty($value) or $value === '$@NONE@$') {
1550 return array();
4413941f 1551 }
adf176d7 1552
ac7af0da 1553 // We have to make sure that users still have the necessary capability,
adf176d7 1554 // it should be faster to fetch them all first and then test if they are present
ac7af0da 1555 // instead of validating them one-by-one.
b0c6dc1c 1556 $users = get_users_by_capability(context_system::instance(), $capability);
adf176d7
PS
1557 if ($includeadmins) {
1558 $admins = get_admins();
1559 foreach ($admins as $admin) {
1560 $users[$admin->id] = $admin;
1561 }
1562 }
1563
1564 if ($value === '$@ALL@$') {
1565 return $users;
1566 }
1567
ac7af0da 1568 $result = array(); // Result in correct order.
adf176d7
PS
1569 $allowed = explode(',', $value);
1570 foreach ($allowed as $uid) {
1571 if (isset($users[$uid])) {
1572 $user = $users[$uid];
1573 $result[$user->id] = $user;
1574 }
1575 }
1576
1577 return $result;
4413941f 1578}
1579
f87eab7e
PS
1580
1581/**
ac7af0da 1582 * Invalidates browser caches and cached data in temp.
52642d0d
SH
1583 *
1584 * IMPORTANT - If you are adding anything here to do with the cache directory you should also have a look at
ac7af0da 1585 * {@link phpunit_util::reset_dataroot()}
52642d0d 1586 *
f87eab7e
PS
1587 * @return void
1588 */
1589function purge_all_caches() {
d79d5ac2 1590 global $CFG, $DB;
f87eab7e 1591
f87eab7e
PS
1592 reset_text_filters_cache();
1593 js_reset_all_caches();
1594 theme_reset_all_caches();
1595 get_string_manager()->reset_caches();
2f1e464a 1596 core_text::reset_caches();
e87214bd
PS
1597 if (class_exists('core_plugin_manager')) {
1598 core_plugin_manager::reset_caches();
bde002b8 1599 }
f87eab7e 1600
299cfee5
MG
1601 // Bump up cacherev field for all courses.
1602 try {
1603 increment_revision_number('course', 'cacherev', '');
1604 } catch (moodle_exception $e) {
1605 // Ignore exception since this function is also called before upgrade script when field course.cacherev does not exist yet.
1606 }
1607
d79d5ac2 1608 $DB->reset_caches();
d6a1f63b
SH
1609 cache_helper::purge_all();
1610
ac7af0da 1611 // Purge all other caches: rss, simplepie, etc.
365bec4c 1612 remove_dir($CFG->cachedir.'', true);
f87eab7e 1613
ac7af0da 1614 // Make sure cache dir is writable, throws exception if not.
5a87c912 1615 make_cache_directory('');
f87eab7e 1616
85b38061
PS
1617 // This is the only place where we purge local caches, we are only adding files there.
1618 // The $CFG->localcachedirpurged flag forces local directories to be purged on cluster nodes.
1619 remove_dir($CFG->localcachedir, true);
1620 set_config('localcachedirpurged', time());
1621 make_localcache_directory('', true);
309ae892 1622 \core\task\manager::clear_static_caches();
f87eab7e
PS
1623}
1624
bafd7e78 1625/**
1626 * Get volatile flags
1627 *
1628 * @param string $type
ac7af0da
SH
1629 * @param int $changedsince default null
1630 * @return array records array
bafd7e78 1631 */
ac7af0da 1632function get_cache_flags($type, $changedsince = null) {
ae040d4b 1633 global $DB;
bafd7e78 1634
ac7af0da 1635 $params = array('type' => $type, 'expiry' => time());
ae040d4b 1636 $sqlwhere = "flagtype = :type AND expiry >= :expiry";
ac7af0da 1637 if ($changedsince !== null) {
ae040d4b 1638 $params['changedsince'] = $changedsince;
1639 $sqlwhere .= " AND timemodified > :changedsince";
bafd7e78 1640 }
1641 $cf = array();
ae040d4b 1642 if ($flags = $DB->get_records_select('cache_flags', $sqlwhere, $params, '', 'name,value')) {
bafd7e78 1643 foreach ($flags as $flag) {
1644 $cf[$flag->name] = $flag->value;
1645 }
1646 }
1647 return $cf;
1648}
1649
a489cf72 1650/**
1651 * Get volatile flags
1652 *
1653 * @param string $type
1654 * @param string $name
ac7af0da
SH
1655 * @param int $changedsince default null
1656 * @return string|false The cache flag value or false
a489cf72 1657 */
ac7af0da 1658function get_cache_flag($type, $name, $changedsince=null) {
ae040d4b 1659 global $DB;
a489cf72 1660
ac7af0da 1661 $params = array('type' => $type, 'name' => $name, 'expiry' => time());
a489cf72 1662
ae040d4b 1663 $sqlwhere = "flagtype = :type AND name = :name AND expiry >= :expiry";
ac7af0da 1664 if ($changedsince !== null) {
ae040d4b 1665 $params['changedsince'] = $changedsince;
1666 $sqlwhere .= " AND timemodified > :changedsince";
a489cf72 1667 }
ae040d4b 1668
1669 return $DB->get_field_select('cache_flags', 'value', $sqlwhere, $params);
a489cf72 1670}
bafd7e78 1671
1672/**
1673 * Set a volatile flag
1674 *
1675 * @param string $type the "type" namespace for the key
1676 * @param string $name the key to set
ac7af0da 1677 * @param string $value the value to set (without magic quotes) - null will remove the flag
bafd7e78 1678 * @param int $expiry (optional) epoch indicating expiry - defaults to now()+ 24hs
0d0a8bf6 1679 * @return bool Always returns true
bafd7e78 1680 */
ac7af0da 1681function set_cache_flag($type, $name, $value, $expiry = null) {
ae040d4b 1682 global $DB;
bafd7e78 1683
1684 $timemodified = time();
ac7af0da 1685 if ($expiry === null || $expiry < $timemodified) {
bafd7e78 1686 $expiry = $timemodified + 24 * 60 * 60;
1687 } else {
1688 $expiry = (int)$expiry;
1689 }
1690
ac7af0da
SH
1691 if ($value === null) {
1692 unset_cache_flag($type, $name);
013376de 1693 return true;
bafd7e78 1694 }
1695
ac7af0da
SH
1696 if ($f = $DB->get_record('cache_flags', array('name' => $name, 'flagtype' => $type), '*', IGNORE_MULTIPLE)) {
1697 // This is a potential problem in DEBUG_DEVELOPER.
128f0984 1698 if ($f->value == $value and $f->expiry == $expiry and $f->timemodified == $timemodified) {
ac7af0da 1699 return true; // No need to update.
128f0984 1700 }
ae040d4b 1701 $f->value = $value;
bafd7e78 1702 $f->expiry = $expiry;
1703 $f->timemodified = $timemodified;
013376de 1704 $DB->update_record('cache_flags', $f);
bafd7e78 1705 } else {
365a5941 1706 $f = new stdClass();
bafd7e78 1707 $f->flagtype = $type;
1708 $f->name = $name;
ae040d4b 1709 $f->value = $value;
bafd7e78 1710 $f->expiry = $expiry;
1711 $f->timemodified = $timemodified;
013376de 1712 $DB->insert_record('cache_flags', $f);
bafd7e78 1713 }
013376de 1714 return true;
bafd7e78 1715}
1716
1717/**
1718 * Removes a single volatile flag
1719 *
1720 * @param string $type the "type" namespace for the key
1721 * @param string $name the key to set
bafd7e78 1722 * @return bool
1723 */
1724function unset_cache_flag($type, $name) {
ae040d4b 1725 global $DB;
ac7af0da 1726 $DB->delete_records('cache_flags', array('name' => $name, 'flagtype' => $type));
013376de 1727 return true;
bafd7e78 1728}
1729
1730/**
1731 * Garbage-collect volatile flags
1732 *
0d0a8bf6 1733 * @return bool Always returns true
bafd7e78 1734 */
1735function gc_cache_flags() {
ae040d4b 1736 global $DB;
013376de 1737 $DB->delete_records_select('cache_flags', 'expiry < ?', array(time()));
1738 return true;
bafd7e78 1739}
a4080313 1740
ac7af0da 1741// USER PREFERENCE API.
2660377f 1742
7cf1c7bd 1743/**
39461de3
PS
1744 * Refresh user preference cache. This is used most often for $USER
1745 * object that is stored in session, but it also helps with performance in cron script.
0d0a8bf6 1746 *
39461de3
PS
1747 * Preferences for each user are loaded on first use on every page, then again after the timeout expires.
1748 *
4d6b40a0
GGC
1749 * @package core
1750 * @category preference
1751 * @access public
1752 * @param stdClass $user User object. Preferences are preloaded into 'preference' property
1753 * @param int $cachelifetime Cache life time on the current page (in seconds)
1754 * @throws coding_exception
1755 * @return null
7cf1c7bd 1756 */
39461de3
PS
1757function check_user_preferences_loaded(stdClass $user, $cachelifetime = 120) {
1758 global $DB;
ac7af0da
SH
1759 // Static cache, we need to check on each page load, not only every 2 minutes.
1760 static $loadedusers = array();
2660377f 1761
39461de3
PS
1762 if (!isset($user->id)) {
1763 throw new coding_exception('Invalid $user parameter in check_user_preferences_loaded() call, missing id field');
1764 }
2660377f 1765
39461de3 1766 if (empty($user->id) or isguestuser($user->id)) {
ac7af0da 1767 // No permanent storage for not-logged-in users and guest.
39461de3
PS
1768 if (!isset($user->preference)) {
1769 $user->preference = array();
2660377f 1770 }
39461de3 1771 return;
2660377f 1772 }
70812e39 1773
39461de3 1774 $timenow = time();
070e2616 1775
39461de3
PS
1776 if (isset($loadedusers[$user->id]) and isset($user->preference) and isset($user->preference['_lastloaded'])) {
1777 // Already loaded at least once on this page. Are we up to date?
1778 if ($user->preference['_lastloaded'] + $cachelifetime > $timenow) {
ac7af0da 1779 // No need to reload - we are on the same page and we loaded prefs just a moment ago.
39461de3 1780 return;
70812e39 1781
39461de3 1782 } else if (!get_cache_flag('userpreferenceschanged', $user->id, $user->preference['_lastloaded'])) {
ac7af0da 1783 // No change since the lastcheck on this page.
39461de3
PS
1784 $user->preference['_lastloaded'] = $timenow;
1785 return;
70812e39 1786 }
c6d15803 1787 }
346c3e2f 1788
ac7af0da 1789 // OK, so we have to reload all preferences.
39461de3 1790 $loadedusers[$user->id] = true;
ac7af0da 1791 $user->preference = $DB->get_records_menu('user_preferences', array('userid' => $user->id), '', 'name,value'); // All values.
39461de3 1792 $user->preference['_lastloaded'] = $timenow;
2660377f 1793}
1794
1795/**
ac7af0da 1796 * Called from set/unset_user_preferences, so that the prefs can be correctly reloaded in different sessions.
39461de3
PS
1797 *
1798 * NOTE: internal function, do not call from other code.
0d0a8bf6 1799 *
4d6b40a0 1800 * @package core
ac7af0da
SH
1801 * @access private
1802 * @param integer $userid the user whose prefs were changed.
2660377f 1803 */
1804function mark_user_preferences_changed($userid) {
39461de3
PS
1805 global $CFG;
1806
1807 if (empty($userid) or isguestuser($userid)) {
ac7af0da 1808 // No cache flags for guest and not-logged-in users.
39461de3 1809 return;
2660377f 1810 }
39461de3 1811
2660377f 1812 set_cache_flag('userpreferenceschanged', $userid, 1, time() + $CFG->sessiontimeout);
70812e39 1813}
1814
7cf1c7bd 1815/**
39461de3 1816 * Sets a preference for the specified user.
0d0a8bf6 1817 *
4d6b40a0 1818 * If a $user object is submitted it's 'preference' property is used for the preferences cache.
0d0a8bf6 1819 *
4d6b40a0
GGC
1820 * @package core
1821 * @category preference
1822 * @access public
1823 * @param string $name The key to set as preference for the specified user
1824 * @param string $value The value to set for the $name key in the specified user's
1825 * record, null means delete current value.
1826 * @param stdClass|int|null $user A moodle user object or id, null means current user
1827 * @throws coding_exception
1828 * @return bool Always true or exception
7cf1c7bd 1829 */
39461de3 1830function set_user_preference($name, $value, $user = null) {
ae040d4b 1831 global $USER, $DB;
70812e39 1832
39461de3
PS
1833 if (empty($name) or is_numeric($name) or $name === '_lastloaded') {
1834 throw new coding_exception('Invalid preference name in set_user_preference() call');
70812e39 1835 }
1836
39461de3 1837 if (is_null($value)) {
ac7af0da 1838 // Null means delete current.
39461de3
PS
1839 return unset_user_preference($name, $user);
1840 } else if (is_object($value)) {
1841 throw new coding_exception('Invalid value in set_user_preference() call, objects are not allowed');
1842 } else if (is_array($value)) {
1843 throw new coding_exception('Invalid value in set_user_preference() call, arrays are not allowed');
1844 }
ac7af0da 1845 // Value column maximum length is 1333 characters.
39461de3 1846 $value = (string)$value;
2f1e464a 1847 if (core_text::strlen($value) > 1333) {
8e54ce97
AD
1848 throw new coding_exception('Invalid value in set_user_preference() call, value is is too long for the value column');
1849 }
39461de3
PS
1850
1851 if (is_null($user)) {
1852 $user = $USER;
1853 } else if (isset($user->id)) {
ac7af0da 1854 // It is a valid object.
39461de3 1855 } else if (is_numeric($user)) {
ac7af0da 1856 $user = (object)array('id' => (int)$user);
346c3e2f 1857 } else {
39461de3 1858 throw new coding_exception('Invalid $user parameter in set_user_preference() call');
346c3e2f 1859 }
1860
39461de3
PS
1861 check_user_preferences_loaded($user);
1862
1863 if (empty($user->id) or isguestuser($user->id)) {
ac7af0da 1864 // No permanent storage for not-logged-in users and guest.
39461de3
PS
1865 $user->preference[$name] = $value;
1866 return true;
1867 }
346c3e2f 1868
ac7af0da 1869 if ($preference = $DB->get_record('user_preferences', array('userid' => $user->id, 'name' => $name))) {
39461de3 1870 if ($preference->value === $value and isset($user->preference[$name]) and $user->preference[$name] === $value) {
ac7af0da 1871 // Preference already set to this value.
a1244706 1872 return true;
1873 }
ac7af0da 1874 $DB->set_field('user_preferences', 'value', $value, array('id' => $preference->id));
70812e39 1875
1876 } else {
365a5941 1877 $preference = new stdClass();
39461de3 1878 $preference->userid = $user->id;
ae040d4b 1879 $preference->name = $name;
39461de3 1880 $preference->value = $value;
013376de 1881 $DB->insert_record('user_preferences', $preference);
2660377f 1882 }
1883
ac7af0da 1884 // Update value in cache.
39461de3
PS
1885 $user->preference[$name] = $value;
1886
ac7af0da 1887 // Set reload flag for other sessions.
39461de3 1888 mark_user_preferences_changed($user->id);
346c3e2f 1889
013376de 1890 return true;
2660377f 1891}
1892
1893/**
1894 * Sets a whole array of preferences for the current user
0d0a8bf6 1895 *
4d6b40a0 1896 * If a $user object is submitted it's 'preference' property is used for the preferences cache.
39461de3 1897 *
4d6b40a0
GGC
1898 * @package core
1899 * @category preference
1900 * @access public
1901 * @param array $prefarray An array of key/value pairs to be set
1902 * @param stdClass|int|null $user A moodle user object or id, null means current user
1903 * @return bool Always true or exception
2660377f 1904 */
39461de3 1905function set_user_preferences(array $prefarray, $user = null) {
2660377f 1906 foreach ($prefarray as $name => $value) {
39461de3 1907 set_user_preference($name, $value, $user);
2660377f 1908 }
013376de 1909 return true;
70812e39 1910}
1911
6eb3e776 1912/**
1913 * Unsets a preference completely by deleting it from the database
0d0a8bf6 1914 *
4d6b40a0 1915 * If a $user object is submitted it's 'preference' property is used for the preferences cache.
0d0a8bf6 1916 *
4d6b40a0
GGC
1917 * @package core
1918 * @category preference
1919 * @access public
1920 * @param string $name The key to unset as preference for the specified user
1921 * @param stdClass|int|null $user A moodle user object or id, null means current user
1922 * @throws coding_exception
1923 * @return bool Always true or exception
6eb3e776 1924 */
39461de3 1925function unset_user_preference($name, $user = null) {
ae040d4b 1926 global $USER, $DB;
6eb3e776 1927
39461de3
PS
1928 if (empty($name) or is_numeric($name) or $name === '_lastloaded') {
1929 throw new coding_exception('Invalid preference name in unset_user_preference() call');
1930 }
1931
1932 if (is_null($user)) {
1933 $user = $USER;
1934 } else if (isset($user->id)) {
ac7af0da 1935 // It is a valid object.
39461de3 1936 } else if (is_numeric($user)) {
ac7af0da 1937 $user = (object)array('id' => (int)$user);
346c3e2f 1938 } else {
39461de3 1939 throw new coding_exception('Invalid $user parameter in unset_user_preference() call');
346c3e2f 1940 }
1941
39461de3 1942 check_user_preferences_loaded($user);
013376de 1943
39461de3 1944 if (empty($user->id) or isguestuser($user->id)) {
ac7af0da 1945 // No permanent storage for not-logged-in user and guest.
39461de3
PS
1946 unset($user->preference[$name]);
1947 return true;
70812e39 1948 }
1949
ac7af0da
SH
1950 // Delete from DB.
1951 $DB->delete_records('user_preferences', array('userid' => $user->id, 'name' => $name));
39461de3 1952
ac7af0da 1953 // Delete the preference from cache.
39461de3
PS
1954 unset($user->preference[$name]);
1955
ac7af0da 1956 // Set reload flag for other sessions.
39461de3
PS
1957 mark_user_preferences_changed($user->id);
1958
013376de 1959 return true;
70812e39 1960}
1961
7cf1c7bd 1962/**
0d0a8bf6 1963 * Used to fetch user preference(s)
1964 *
7cf1c7bd 1965 * If no arguments are supplied this function will return
361855e6 1966 * all of the current user preferences as an array.
0d0a8bf6 1967 *
7cf1c7bd 1968 * If a name is specified then this function
1969 * attempts to return that particular preference value. If
1970 * none is found, then the optional value $default is returned,
ac7af0da 1971 * otherwise null.
0d0a8bf6 1972 *
4d6b40a0 1973 * If a $user object is submitted it's 'preference' property is used for the preferences cache.
39461de3 1974 *
4d6b40a0
GGC
1975 * @package core
1976 * @category preference
1977 * @access public
1978 * @param string $name Name of the key to use in finding a preference value
1979 * @param mixed|null $default Value to be returned if the $name key is not set in the user preferences
1980 * @param stdClass|int|null $user A moodle user object or id, null means current user
1981 * @throws coding_exception
1982 * @return string|mixed|null A string containing the value of a single preference. An
1983 * array with all of the preferences or null
7cf1c7bd 1984 */
39461de3
PS
1985function get_user_preferences($name = null, $default = null, $user = null) {
1986 global $USER;
70812e39 1987
39461de3 1988 if (is_null($name)) {
ac7af0da 1989 // All prefs.
39461de3
PS
1990 } else if (is_numeric($name) or $name === '_lastloaded') {
1991 throw new coding_exception('Invalid preference name in get_user_preferences() call');
1992 }
346c3e2f 1993
39461de3
PS
1994 if (is_null($user)) {
1995 $user = $USER;
1996 } else if (isset($user->id)) {
ac7af0da 1997 // Is a valid object.
39461de3 1998 } else if (is_numeric($user)) {
ac7af0da 1999 $user = (object)array('id' => (int)$user);
39461de3
PS
2000 } else {
2001 throw new coding_exception('Invalid $user parameter in get_user_preferences() call');
2002 }
2003
2004 check_user_preferences_loaded($user);
346c3e2f 2005
39461de3 2006 if (empty($name)) {
ac7af0da
SH
2007 // All values.
2008 return $user->preference;
39461de3 2009 } else if (isset($user->preference[$name])) {
ac7af0da
SH
2010 // The single string value.
2011 return $user->preference[$name];
346c3e2f 2012 } else {
ac7af0da
SH
2013 // Default value (null if not specified).
2014 return $default;
70812e39 2015 }
70812e39 2016}
2017
ac7af0da 2018// FUNCTIONS FOR HANDLING TIME.
39917a09 2019
7cf1c7bd 2020/**
c6d15803 2021 * Given date parts in user time produce a GMT timestamp.
7cf1c7bd 2022 *
9df12115
RT
2023 * @package core
2024 * @category time
68fbd8e1 2025 * @param int $year The year part to create timestamp of
2026 * @param int $month The month part to create timestamp of
2027 * @param int $day The day part to create timestamp of
2028 * @param int $hour The hour part to create timestamp of
2029 * @param int $minute The minute part to create timestamp of
2030 * @param int $second The second part to create timestamp of
9df12115
RT
2031 * @param int|float|string $timezone Timezone modifier, used to calculate GMT time offset.
2032 * if 99 then default user's timezone is used {@link http://docs.moodle.org/dev/Time_API#Timezone}
6a0bf5c4
RT
2033 * @param bool $applydst Toggle Daylight Saving Time, default true, will be
2034 * applied only if timezone is 99 or string.
9df12115 2035 * @return int GMT timestamp
7cf1c7bd 2036 */
9f1f6daf 2037function make_timestamp($year, $month=1, $day=1, $hour=0, $minute=0, $second=0, $timezone=99, $applydst=true) {
39917a09 2038
ac7af0da 2039 // Save input timezone, required for dst offset check.
6a0bf5c4 2040 $passedtimezone = $timezone;
33998d30 2041
dddb014a 2042 $timezone = get_user_timezone_offset($timezone);
2043
ac7af0da
SH
2044 if (abs($timezone) > 13) {
2045 // Server time.
68fbd8e1 2046 $time = mktime((int)$hour, (int)$minute, (int)$second, (int)$month, (int)$day, (int)$year);
03c17ddf 2047 } else {
68fbd8e1 2048 $time = gmmktime((int)$hour, (int)$minute, (int)$second, (int)$month, (int)$day, (int)$year);
196f2619 2049 $time = usertime($time, $timezone);
6a0bf5c4 2050
ac7af0da 2051 // Apply dst for string timezones or if 99 then try dst offset with user's default timezone.
6a0bf5c4
RT
2052 if ($applydst && ((99 == $passedtimezone) || !is_numeric($passedtimezone))) {
2053 $time -= dst_offset_on($time, $passedtimezone);
28c66824 2054 }
9f1f6daf 2055 }
2056
196f2619 2057 return $time;
85cafb3e 2058
39917a09 2059}
2060
7cf1c7bd 2061/**
0d0a8bf6 2062 * Format a date/time (seconds) as weeks, days, hours etc as needed
2063 *
7cf1c7bd 2064 * Given an amount of time in seconds, returns string
5602f7cf 2065 * formatted nicely as weeks, days, hours etc as needed
7cf1c7bd 2066 *
9df12115
RT
2067 * @package core
2068 * @category time
2f87145b 2069 * @uses MINSECS
2070 * @uses HOURSECS
2071 * @uses DAYSECS
5602f7cf 2072 * @uses YEARSECS
0d0a8bf6 2073 * @param int $totalsecs Time in seconds
ac7af0da 2074 * @param stdClass $str Should be a time object
0d0a8bf6 2075 * @return string A nicely formatted date/time string
7cf1c7bd 2076 */
ac7af0da 2077function format_time($totalsecs, $str = null) {
c7e3ac2a 2078
6b174680 2079 $totalsecs = abs($totalsecs);
c7e3ac2a 2080
ac7af0da
SH
2081 if (!$str) {
2082 // Create the str structure the slow way.
b85b25eb 2083 $str = new stdClass();
b0ccd3fb 2084 $str->day = get_string('day');
2085 $str->days = get_string('days');
2086 $str->hour = get_string('hour');
2087 $str->hours = get_string('hours');
2088 $str->min = get_string('min');
2089 $str->mins = get_string('mins');
2090 $str->sec = get_string('sec');
2091 $str->secs = get_string('secs');
5602f7cf 2092 $str->year = get_string('year');
2093 $str->years = get_string('years');
8dbed6be 2094 }
2095
5602f7cf 2096 $years = floor($totalsecs/YEARSECS);
2097 $remainder = $totalsecs - ($years*YEARSECS);
5602f7cf 2098 $days = floor($remainder/DAYSECS);
7a5672c9 2099 $remainder = $totalsecs - ($days*DAYSECS);
2100 $hours = floor($remainder/HOURSECS);
2101 $remainder = $remainder - ($hours*HOURSECS);
2102 $mins = floor($remainder/MINSECS);
2103 $secs = $remainder - ($mins*MINSECS);
8dbed6be 2104
2105 $ss = ($secs == 1) ? $str->sec : $str->secs;
2106 $sm = ($mins == 1) ? $str->min : $str->mins;
2107 $sh = ($hours == 1) ? $str->hour : $str->hours;
2108 $sd = ($days == 1) ? $str->day : $str->days;
5602f7cf 2109 $sy = ($years == 1) ? $str->year : $str->years;
8dbed6be 2110
5602f7cf 2111 $oyears = '';
b0ccd3fb 2112 $odays = '';
2113 $ohours = '';
2114 $omins = '';
2115 $osecs = '';
9c9f7d77 2116
ac7af0da
SH
2117 if ($years) {
2118 $oyears = $years .' '. $sy;
2119 }
2120 if ($days) {
2121 $odays = $days .' '. $sd;
2122 }
2123 if ($hours) {
2124 $ohours = $hours .' '. $sh;
2125 }
2126 if ($mins) {
2127 $omins = $mins .' '. $sm;
2128 }
2129 if ($secs) {
2130 $osecs = $secs .' '. $ss;
2131 }
2132
2133 if ($years) {
2134 return trim($oyears .' '. $odays);
2135 }
2136 if ($days) {
2137 return trim($odays .' '. $ohours);
2138 }
2139 if ($hours) {
2140 return trim($ohours .' '. $omins);
2141 }
2142 if ($mins) {
2143 return trim($omins .' '. $osecs);
2144 }
2145 if ($secs) {
2146 return $osecs;
2147 }
b0ccd3fb 2148 return get_string('now');
6b174680 2149}
f9903ed0 2150
7cf1c7bd 2151/**
f59ab4ad 2152 * Returns a formatted string that represents a date in user time.
7cf1c7bd 2153 *
9df12115
RT
2154 * @package core
2155 * @category time
0a0cf09a 2156 * @param int $date the timestamp in UTC, as obtained from the database.
2157 * @param string $format strftime format. You should probably get this using
9df12115 2158 * get_string('strftime...', 'langconfig');
f59ab4ad 2159 * @param int|float|string $timezone by default, uses the user's time zone. if numeric and
9df12115
RT
2160 * not 99 then daylight saving will not be added.
2161 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
0a0cf09a 2162 * @param bool $fixday If true (default) then the leading zero from %d is removed.
9df12115 2163 * If false then the leading zero is maintained.
d9498b38 2164 * @param bool $fixhour If true (default) then the leading zero from %I is removed.
0a0cf09a 2165 * @return string the formatted date/time.
7cf1c7bd 2166 */
d9498b38 2167function userdate($date, $format = '', $timezone = 99, $fixday = true, $fixhour = true) {
6eafa4dd 2168 $calendartype = \core_calendar\type_factory::get_calendar_instance();
f59ab4ad 2169 return $calendartype->timestamp_to_date_string($date, $format, $timezone, $fixday, $fixhour);
873960de 2170}
2171
15396bba
FM
2172/**
2173 * Returns a formatted date ensuring it is UTF-8.
2174 *
2175 * If we are running under Windows convert to Windows encoding and then back to UTF-8
2176 * (because it's impossible to specify UTF-8 to fetch locale info in Win32).
2177 *
2178 * This function does not do any calculation regarding the user preferences and should
2179 * therefore receive the final date timestamp, format and timezone. Timezone being only used
ac7af0da 2180 * to differentiate the use of server time or not (strftime() against gmstrftime()).
15396bba
FM
2181 *
2182 * @param int $date the timestamp.
2183 * @param string $format strftime format.
ac7af0da 2184 * @param int|float $tz the numerical timezone, typically returned by {@link get_user_timezone_offset()}.
15396bba 2185 * @return string the formatted date/time.
5bcfd504 2186 * @since Moodle 2.3.3
15396bba
FM
2187 */
2188function date_format_string($date, $format, $tz = 99) {
2189 global $CFG;
d61d3e82
RT
2190
2191 $localewincharset = null;
2192 // Get the calendar type user is using.
2193 if ($CFG->ostype == 'WINDOWS') {
2194 $calendartype = \core_calendar\type_factory::get_calendar_instance();
2195 $localewincharset = $calendartype->locale_win_charset();
2196 }
2197
15396bba 2198 if (abs($tz) > 13) {
d61d3e82 2199 if ($localewincharset) {
2f1e464a 2200 $format = core_text::convert($format, 'utf-8', $localewincharset);
15396bba 2201 $datestring = strftime($format, $date);
2f1e464a 2202 $datestring = core_text::convert($datestring, $localewincharset, 'utf-8');
15396bba
FM
2203 } else {
2204 $datestring = strftime($format, $date);
2205 }
2206 } else {
d61d3e82 2207 if ($localewincharset) {
2f1e464a 2208 $format = core_text::convert($format, 'utf-8', $localewincharset);
15396bba 2209 $datestring = gmstrftime($format, $date);
2f1e464a 2210 $datestring = core_text::convert($datestring, $localewincharset, 'utf-8');
15396bba
FM
2211 } else {
2212 $datestring = gmstrftime($format, $date);
2213 }
2214 }
2215 return $datestring;
2216}
2217
7cf1c7bd 2218/**
deed22ea
MN
2219 * Given a $time timestamp in GMT (seconds since epoch),
2220 * returns an array that represents the date in user time
7cf1c7bd 2221 *
9df12115
RT
2222 * @package core
2223 * @category time
deed22ea
MN
2224 * @uses HOURSECS
2225 * @param int $time Timestamp in GMT
2226 * @param float|int|string $timezone offset's time with timezone, if float and not 99, then no
2227 * dst offset is applied {@link http://docs.moodle.org/dev/Time_API#Timezone}
2228 * @return array An array that represents the date in user time
7cf1c7bd 2229 */
deed22ea
MN
2230function usergetdate($time, $timezone=99) {
2231
2232 // Save input timezone, required for dst offset check.
2233 $passedtimezone = $timezone;
2234
2235 $timezone = get_user_timezone_offset($timezone);
2236
2237 if (abs($timezone) > 13) {
2238 // Server time.
2239 return getdate($time);
2240 }
2241
2242 // Add daylight saving offset for string timezones only, as we can't get dst for
2243 // float values. if timezone is 99 (user default timezone), then try update dst.
2244 if ($passedtimezone == 99 || !is_numeric($passedtimezone)) {
2245 $time += dst_offset_on($time, $passedtimezone);
2246 }
2247
2248 $time += intval((float)$timezone * HOURSECS);
2249
2250 $datestring = gmstrftime('%B_%A_%j_%Y_%m_%w_%d_%H_%M_%S', $time);
2251
2252 // Be careful to ensure the returned array matches that produced by getdate() above.
2253 list(
2254 $getdate['month'],
2255 $getdate['weekday'],
2256 $getdate['yday'],
2257 $getdate['year'],
2258 $getdate['mon'],
2259 $getdate['wday'],
2260 $getdate['mday'],
2261 $getdate['hours'],
2262 $getdate['minutes'],
2263 $getdate['seconds']
2264 ) = explode('_', $datestring);
2265
2266 // Set correct datatype to match with getdate().
2267 $getdate['seconds'] = (int)$getdate['seconds'];
2268 $getdate['yday'] = (int)$getdate['yday'] - 1; // The function gmstrftime returns 0 through 365.
2269 $getdate['year'] = (int)$getdate['year'];
2270 $getdate['mon'] = (int)$getdate['mon'];
2271 $getdate['wday'] = (int)$getdate['wday'];
2272 $getdate['mday'] = (int)$getdate['mday'];
2273 $getdate['hours'] = (int)$getdate['hours'];
2274 $getdate['minutes'] = (int)$getdate['minutes'];
2275 return $getdate;
d552ead0 2276}
2277
7cf1c7bd 2278/**
2279 * Given a GMT timestamp (seconds since epoch), offsets it by
2280 * the timezone. eg 3pm in India is 3pm GMT - 7 * 3600 seconds
2281 *
9df12115
RT
2282 * @package core
2283 * @category time
2f87145b 2284 * @uses HOURSECS
9df12115
RT
2285 * @param int $date Timestamp in GMT
2286 * @param float|int|string $timezone timezone to calculate GMT time offset before
2287 * calculating user time, 99 is default user timezone
2288 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
c6d15803 2289 * @return int
7cf1c7bd 2290 */
d552ead0 2291function usertime($date, $timezone=99) {
a36166d3 2292
494b9296 2293 $timezone = get_user_timezone_offset($timezone);
2665e47a 2294
0431bd7c 2295 if (abs($timezone) > 13) {
d552ead0 2296 return $date;
2297 }
7a5672c9 2298 return $date - (int)($timezone * HOURSECS);
d552ead0 2299}
2300
8c3dba73 2301/**
2302 * Given a time, return the GMT timestamp of the most recent midnight
2303 * for the current user.
2304 *
9df12115
RT
2305 * @package core
2306 * @category time
e34d817e 2307 * @param int $date Timestamp in GMT
9df12115
RT
2308 * @param float|int|string $timezone timezone to calculate GMT time offset before
2309 * calculating user midnight time, 99 is default user timezone
2310 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
0d0a8bf6 2311 * @return int Returns a GMT timestamp
8c3dba73 2312 */
edf7fe8c 2313function usergetmidnight($date, $timezone=99) {
edf7fe8c 2314
edf7fe8c 2315 $userdate = usergetdate($date, $timezone);
4606d9bb 2316
ac7af0da 2317 // Time of midnight of this user's day, in GMT.
02f0527d 2318 return make_timestamp($userdate['year'], $userdate['mon'], $userdate['mday'], 0, 0, 0, $timezone);
edf7fe8c 2319
2320}
2321
7cf1c7bd 2322/**
2323 * Returns a string that prints the user's timezone
2324 *
9df12115
RT
2325 * @package core
2326 * @category time
2327 * @param float|int|string $timezone timezone to calculate GMT time offset before
2328 * calculating user timezone, 99 is default user timezone
2329 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
7cf1c7bd 2330 * @return string
2331 */
d552ead0 2332function usertimezone($timezone=99) {
d552ead0 2333
0c244315 2334 $tz = get_user_timezone($timezone);
f30fe8d0 2335
0c244315 2336 if (!is_float($tz)) {
2337 return $tz;
d552ead0 2338 }
0c244315 2339
ac7af0da
SH
2340 if (abs($tz) > 13) {
2341 // Server time.
0c244315 2342 return get_string('serverlocaltime');
2343 }
2344
ac7af0da
SH
2345 if ($tz == intval($tz)) {
2346 // Don't show .0 for whole hours.
0c244315 2347 $tz = intval($tz);
2348 }
2349
ac7af0da 2350 if ($tz == 0) {
61b420ac 2351 return 'UTC';
ac7af0da 2352 } else if ($tz > 0) {
61b420ac 2353 return 'UTC+'.$tz;
ac7af0da 2354 } else {
61b420ac 2355 return 'UTC'.$tz;
d552ead0 2356 }
e1ecf0a0 2357
f9903ed0 2358}
2359
7cf1c7bd 2360/**
2361 * Returns a float which represents the user's timezone difference from GMT in hours
2362 * Checks various settings and picks the most dominant of those which have a value
2363 *
9df12115
RT
2364 * @package core
2365 * @category time
2366 * @param float|int|string $tz timezone to calculate GMT time offset for user,
2367 * 99 is default user timezone
2368 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
0d0a8bf6 2369 * @return float
7cf1c7bd 2370 */
494b9296 2371function get_user_timezone_offset($tz = 99) {
e8904995 2372 $tz = get_user_timezone($tz);
c9e55a25 2373
7b9e355e 2374 if (is_float($tz)) {
2375 return $tz;
2376 } else {
e8904995 2377 $tzrecord = get_timezone_record($tz);
7b9e355e 2378 if (empty($tzrecord)) {
e8904995 2379 return 99.0;
2380 }
4f2dbde9 2381 return (float)$tzrecord->gmtoff / HOURMINS;
e8904995 2382 }
2383}
2384
61460dd6 2385/**
2386 * Returns an int which represents the systems's timezone difference from GMT in seconds
0d0a8bf6 2387 *
9df12115
RT
2388 * @package core
2389 * @category time
2390 * @param float|int|string $tz timezone for which offset is required.
2391 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
2392 * @return int|bool if found, false is timezone 99 or error
61460dd6 2393 */
2394function get_timezone_offset($tz) {
61460dd6 2395 if ($tz == 99) {
2396 return false;
2397 }
2398
2399 if (is_numeric($tz)) {
2400 return intval($tz * 60*60);
2401 }
2402
2403 if (!$tzrecord = get_timezone_record($tz)) {
2404 return false;
2405 }
2406 return intval($tzrecord->gmtoff * 60);
2407}
2408
bbd3f2c4 2409/**
b2b68362 2410 * Returns a float or a string which denotes the user's timezone
2411 * 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)
2412 * means that for this timezone there are also DST rules to be taken into account
2413 * Checks various settings and picks the most dominant of those which have a value
bbd3f2c4 2414 *
9df12115
RT
2415 * @package core
2416 * @category time
2417 * @param float|int|string $tz timezone to calculate GMT time offset before
2418 * calculating user timezone, 99 is default user timezone
2419 * {@link http://docs.moodle.org/dev/Time_API#Timezone}
2420 * @return float|string
bbd3f2c4 2421 */
e8904995 2422function get_user_timezone($tz = 99) {
2423 global $USER, $CFG;
43b59916 2424
f30fe8d0 2425 $timezones = array(
e8904995 2426 $tz,
2427 isset($CFG->forcetimezone) ? $CFG->forcetimezone : 99,
43b59916 2428 isset($USER->timezone) ? $USER->timezone : 99,
2429 isset($CFG->timezone) ? $CFG->timezone : 99,
f30fe8d0 2430 );
43b59916 2431
e8904995 2432 $tz = 99;
43b59916 2433
ac7af0da
SH
2434 // Loop while $tz is, empty but not zero, or 99, and there is another timezone is the array.
2435 while (((empty($tz) && !is_numeric($tz)) || $tz == 99) && $next = each($timezones)) {
e8904995 2436 $tz = $next['value'];
43b59916 2437 }
e8904995 2438 return is_numeric($tz) ? (float) $tz : $tz;
43b59916 2439}
2440
bbd3f2c4 2441/**
f33e1ed4 2442 * Returns cached timezone record for given $timezonename
bbd3f2c4 2443 *
9df12115
RT
2444 * @package core
2445 * @param string $timezonename name of the timezone
2446 * @return stdClass|bool timezonerecord or false
bbd3f2c4 2447 */
43b59916 2448function get_timezone_record($timezonename) {
ac7af0da
SH
2449 global $DB;
2450 static $cache = null;
43b59916 2451
ac7af0da 2452 if ($cache === null) {
43b59916 2453 $cache = array();
2454 }
2455
8edffd15 2456 if (isset($cache[$timezonename])) {
43b59916 2457 return $cache[$timezonename];
f30fe8d0 2458 }
2459
f33e1ed4 2460 return $cache[$timezonename] = $DB->get_record_sql('SELECT * FROM {timezone}
daac3835 2461 WHERE name = ? ORDER BY year DESC', array($timezonename), IGNORE_MULTIPLE);
f30fe8d0 2462}
f9903ed0 2463
bbd3f2c4 2464/**
0d0a8bf6 2465 * Build and store the users Daylight Saving Time (DST) table
bbd3f2c4 2466 *
9df12115 2467 * @package core
ac7af0da
SH
2468 * @param int $fromyear Start year for the table, defaults to 1971
2469 * @param int $toyear End year for the table, defaults to 2035
2470 * @param int|float|string $strtimezone timezone to check if dst should be applied.
bbd3f2c4 2471 * @return bool
2472 */
ac7af0da
SH
2473function calculate_user_dst_table($fromyear = null, $toyear = null, $strtimezone = null) {
2474 global $SESSION, $DB;
85cafb3e 2475
33998d30 2476 $usertz = get_user_timezone($strtimezone);
7cb29a3d 2477
989585e9 2478 if (is_float($usertz)) {
ac7af0da 2479 // Trivial timezone, no DST.
989585e9 2480 return false;
2481 }
2482
2280ecf5 2483 if (!empty($SESSION->dst_offsettz) && $SESSION->dst_offsettz != $usertz) {
ac7af0da 2484 // We have pre-calculated values, but the user's effective TZ has changed in the meantime, so reset.
2280ecf5 2485 unset($SESSION->dst_offsets);
2486 unset($SESSION->dst_range);
830a2bbd 2487 }
2488
ac7af0da
SH
2489 if (!empty($SESSION->dst_offsets) && empty($fromyear) && empty($toyear)) {
2490 // Repeat calls which do not request specific year ranges stop here, we have already calculated the table.
2491 // This will be the return path most of the time, pretty light computationally.
830a2bbd 2492 return true;
85cafb3e 2493 }
2494
ac7af0da 2495 // Reaching here means we either need to extend our table or create it from scratch.
989585e9 2496
ac7af0da 2497 // Remember which TZ we calculated these changes for.
2280ecf5 2498 $SESSION->dst_offsettz = $usertz;
989585e9 2499
ac7af0da
SH
2500 if (empty($SESSION->dst_offsets)) {
2501 // If we 're creating from scratch, put the two guard elements in there.
2502 $SESSION->dst_offsets = array(1 => null, 0 => null);
830a2bbd 2503 }
ac7af0da
SH
2504 if (empty($SESSION->dst_range)) {
2505 // If creating from scratch.
2506 $from = max((empty($fromyear) ? intval(date('Y')) - 3 : $fromyear), 1971);
2507 $to = min((empty($toyear) ? intval(date('Y')) + 3 : $toyear), 2035);
830a2bbd 2508
ac7af0da 2509 // Fill in the array with the extra years we need to process.
830a2bbd 2510 $yearstoprocess = array();
ac7af0da 2511 for ($i = $from; $i <= $to; ++$i) {
830a2bbd 2512 $yearstoprocess[] = $i;
2513 }
2514
ac7af0da 2515 // Take note of which years we have processed for future calls.
2280ecf5 2516 $SESSION->dst_range = array($from, $to);
ac7af0da
SH
2517 } else {
2518 // If needing to extend the table, do the same.
830a2bbd 2519 $yearstoprocess = array();
2520
ac7af0da
SH
2521 $from = max((empty($fromyear) ? $SESSION->dst_range[0] : $fromyear), 1971);
2522 $to = min((empty($toyear) ? $SESSION->dst_range[1] : $toyear), 2035);
830a2bbd 2523
ac7af0da
SH
2524 if ($from < $SESSION->dst_range[0]) {
2525 // Take note of which years we need to process and then note that we have processed them for future calls.
2526 for ($i = $from; $i < $SESSION->dst_range[0]; ++$i) {
830a2bbd 2527 $yearstoprocess[] = $i;
2528 }
2280ecf5 2529 $SESSION->dst_range[0] = $from;
830a2bbd 2530 }
ac7af0da
SH
2531 if ($to > $SESSION->dst_range[1]) {
2532 // Take note of which years we need to process and then note that we have processed them for future calls.
2533 for ($i = $SESSION->dst_range[1] + 1; $i <= $to; ++$i) {
830a2bbd 2534 $yearstoprocess[] = $i;
2535 }
2280ecf5 2536 $SESSION->dst_range[1] = $to;
830a2bbd 2537 }
2538 }
2539
ac7af0da
SH
2540 if (empty($yearstoprocess)) {
2541 // This means that there was a call requesting a SMALLER range than we have already calculated.
830a2bbd 2542 return true;
2543 }
2544
2545 // From now on, we know that the array has at least the two guard elements, and $yearstoprocess has the years we need
2546 // Also, the array is sorted in descending timestamp order!
2547
ac7af0da 2548 // Get DB data.
6a5dc27c 2549
ac7af0da
SH
2550 static $presetscache = array();
2551 if (!isset($presetscache[$usertz])) {
2552 $presetscache[$usertz] = $DB->get_records('timezone', array('name' => $usertz),
2553 'year DESC', 'year, gmtoff, dstoff, dst_month, dst_startday, dst_weekday, dst_skipweeks, dst_time, std_month, '.
2554 'std_startday, std_weekday, std_skipweeks, std_time');
6a5dc27c 2555 }
ac7af0da 2556 if (empty($presetscache[$usertz])) {
e789650d 2557 return false;
2558 }
57f1191c 2559
ac7af0da 2560 // Remove ending guard (first element of the array).
2280ecf5 2561 reset($SESSION->dst_offsets);
2562 unset($SESSION->dst_offsets[key($SESSION->dst_offsets)]);
830a2bbd 2563
ac7af0da
SH
2564 // Add all required change timestamps.
2565 foreach ($yearstoprocess as $y) {
2566 // Find the record which is in effect for the year $y.
2567 foreach ($presetscache[$usertz] as $year => $preset) {
2568 if ($year <= $y) {
830a2bbd 2569 break;
c9e72798 2570 }
830a2bbd 2571 }
2572
2573 $changes = dst_changes_for_year($y, $preset);
2574
ac7af0da 2575 if ($changes === null) {
830a2bbd 2576 continue;
2577 }
ac7af0da 2578 if ($changes['dst'] != 0) {
2280ecf5 2579 $SESSION->dst_offsets[$changes['dst']] = $preset->dstoff * MINSECS;
830a2bbd 2580 }
ac7af0da 2581 if ($changes['std'] != 0) {
2280ecf5 2582 $SESSION->dst_offsets[$changes['std']] = 0;
c9e72798 2583 }
85cafb3e 2584 }
42d36497 2585
ac7af0da 2586 // Put in a guard element at the top.
2280ecf5 2587 $maxtimestamp = max(array_keys($SESSION->dst_offsets));
ac7af0da 2588 $SESSION->dst_offsets[($maxtimestamp + DAYSECS)] = null; // DAYSECS is arbitrary, any "small" number will do.
830a2bbd 2589
ac7af0da 2590 // Sort again.
2280ecf5 2591 krsort($SESSION->dst_offsets);
830a2bbd 2592
e789650d 2593 return true;
2594}
42d36497 2595
0d0a8bf6 2596/**
2597 * Calculates the required DST change and returns a Timestamp Array
2598 *
9df12115
RT
2599 * @package core
2600 * @category time
0d0a8bf6 2601 * @uses HOURSECS
2602 * @uses MINSECS
9df12115 2603 * @param int|string $year Int or String Year to focus on
0d0a8bf6 2604 * @param object $timezone Instatiated Timezone object
ac7af0da 2605 * @return array|null Array dst => xx, 0 => xx, std => yy, 1 => yy or null
0d0a8bf6 2606 */
e789650d 2607function dst_changes_for_year($year, $timezone) {
7cb29a3d 2608
ac7af0da
SH
2609 if ($timezone->dst_startday == 0 && $timezone->dst_weekday == 0 &&
2610 $timezone->std_startday == 0 && $timezone->std_weekday == 0) {
2611 return null;
42d36497 2612 }
7cb29a3d 2613
e789650d 2614 $monthdaydst = find_day_in_month($timezone->dst_startday, $timezone->dst_weekday, $timezone->dst_month, $year);
2615 $monthdaystd = find_day_in_month($timezone->std_startday, $timezone->std_weekday, $timezone->std_month, $year);
2616
ac7af0da
SH
2617 list($dsthour, $dstmin) = explode(':', $timezone->dst_time);
2618 list($stdhour, $stdmin) = explode(':', $timezone->std_time);
d2a9f7cc 2619
2f00e1b2
MN
2620 $timedst = make_timestamp($year, $timezone->dst_month, $monthdaydst, 0, 0, 0, 99, false);
2621 $timestd = make_timestamp($year, $timezone->std_month, $monthdaystd, 0, 0, 0, 99, false);
830a2bbd 2622
2623 // Instead of putting hour and minute in make_timestamp(), we add them afterwards.
2624 // This has the advantage of being able to have negative values for hour, i.e. for timezones
2625 // where GMT time would be in the PREVIOUS day than the local one on which DST changes.
2626
ac7af0da
SH
2627 $timedst += $dsthour * HOURSECS + $dstmin * MINSECS;
2628 $timestd += $stdhour * HOURSECS + $stdmin * MINSECS;
42d36497 2629
e789650d 2630 return array('dst' => $timedst, 0 => $timedst, 'std' => $timestd, 1 => $timestd);
42d36497 2631}
2632
0d0a8bf6 2633/**
efb8c375 2634 * Calculates the Daylight Saving Offset for a given date/time (timestamp)
6a0bf5c4 2635 * - Note: Daylight saving only works for string timezones and not for float.
0d0a8bf6 2636 *
9df12115
RT
2637 * @package core
2638 * @category time
0d0a8bf6 2639 * @param int $time must NOT be compensated at all, it has to be a pure timestamp
9df12115
RT
2640 * @param int|float|string $strtimezone timezone for which offset is expected, if 99 or null
2641 * then user's default timezone is used. {@link http://docs.moodle.org/dev/Time_API#Timezone}
0d0a8bf6 2642 * @return int
2643 */
ac7af0da 2644function dst_offset_on($time, $strtimezone = null) {
2280ecf5 2645 global $SESSION;
02f0527d 2646
ac7af0da 2647 if (!calculate_user_dst_table(null, null, $strtimezone) || empty($SESSION->dst_offsets)) {
c9e72798 2648 return 0;
85cafb3e 2649 }
2650
2280ecf5 2651 reset($SESSION->dst_offsets);
ac7af0da
SH
2652 while (list($from, $offset) = each($SESSION->dst_offsets)) {
2653 if ($from <= $time) {
c9e72798 2654 break;
2655 }
2656 }
2657
ac7af0da
SH
2658 // This is the normal return path.
2659 if ($offset !== null) {
830a2bbd 2660 return $offset;
02f0527d 2661 }
02f0527d 2662
830a2bbd 2663 // Reaching this point means we haven't calculated far enough, do it now:
2664 // Calculate extra DST changes if needed and recurse. The recursion always
2665 // moves toward the stopping condition, so will always end.
2666
ac7af0da
SH
2667 if ($from == 0) {
2668 // We need a year smaller than $SESSION->dst_range[0].
2669 if ($SESSION->dst_range[0] == 1971) {
830a2bbd 2670 return 0;
2671 }
ac7af0da 2672 calculate_user_dst_table($SESSION->dst_range[0] - 5, null, $strtimezone);
94c82430 2673 return dst_offset_on($time, $strtimezone);
ac7af0da
SH
2674 } else {
2675 // We need a year larger than $SESSION->dst_range[1].
2676 if ($SESSION->dst_range[1] == 2035) {
830a2bbd 2677 return 0;
2678 }
ac7af0da 2679 calculate_user_dst_table(null, $SESSION->dst_range[1] + 5, $strtimezone);
94c82430 2680 return dst_offset_on($time, $strtimezone);
830a2bbd 2681 }
85cafb3e 2682}
02f0527d 2683
0d0a8bf6 2684/**
9df12115 2685 * Calculates when the day appears in specific month
0d0a8bf6 2686 *
9df12115
RT
2687 * @package core
2688 * @category time
2689 * @param int $startday starting day of the month
2690 * @param int $weekday The day when week starts (normally taken from user preferences)
2691 * @param int $month The month whose day is sought
2692 * @param int $year The year of the month whose day is sought
0d0a8bf6 2693 * @return int
2694 */
28902d99 2695function find_day_in_month($startday, $weekday, $month, $year) {
da304137 2696 $calendartype = \core_calendar\type_factory::get_calendar_instance();
8dc3f6cf 2697
2698 $daysinmonth = days_in_month($month, $year);
da304137 2699 $daysinweek = count($calendartype->get_weekdays());
8dc3f6cf 2700
ac7af0da 2701 if ($weekday == -1) {
28902d99 2702 // Don't care about weekday, so return:
2703 // abs($startday) if $startday != -1
ac7af0da 2704 // $daysinmonth otherwise.
28902d99 2705 return ($startday == -1) ? $daysinmonth : abs($startday);
8dc3f6cf 2706 }
2707
ac7af0da 2708 // From now on we 're looking for a specific weekday.
ac7af0da
SH
2709 // Give "end of month" its actual value, since we know it.
2710 if ($startday == -1) {
28902d99 2711 $startday = -1 * $daysinmonth;
2712 }
2713
ac7af0da 2714 // Starting from day $startday, the sign is the direction.
ac7af0da 2715 if ($startday < 1) {
28902d99 2716 $startday = abs($startday);
da304137 2717 $lastmonthweekday = dayofweek($daysinmonth, $month, $year);
8dc3f6cf 2718
ac7af0da 2719 // This is the last such weekday of the month.
8dc3f6cf 2720 $lastinmonth = $daysinmonth + $weekday - $lastmonthweekday;
ac7af0da 2721 if ($lastinmonth > $daysinmonth) {
da304137 2722 $lastinmonth -= $daysinweek;
42d36497 2723 }
8dc3f6cf 2724
ac7af0da
SH
2725 // Find the first such weekday <= $startday.
2726 while ($lastinmonth > $startday) {
da304137 2727 $lastinmonth -= $daysinweek;
42d36497 2728 }
8dc3f6cf 2729
2730 return $lastinmonth;
ac7af0da 2731 } else {
da304137 2732 $indexweekday = dayofweek($startday, $month, $year);
42d36497 2733
8dc3f6cf 2734 $diff = $weekday - $indexweekday;
ac7af0da 2735 if ($diff < 0) {
da304137 2736 $diff += $daysinweek;
42d36497 2737 }
42d36497 2738
ac7af0da 2739 // This is the first such weekday of the month equal to or after $startday.
28902d99 2740 $firstfromindex = $startday + $diff;
42d36497 2741
8dc3f6cf 2742 return $firstfromindex;
8dc3f6cf 2743 }
42d36497 2744}
2745
bbd3f2c4 2746/**
2747 * Calculate the number of days in a given month
2748 *
9df12115
RT
2749 * @package core
2750 * @category time
bbd3f2c4 2751 * @param int $month The month whose day count is sought
2752 * @param int $year The year of the month whose day count is sought
2753 * @return int
2754 */
42d36497 2755function days_in_month($month, $year) {
da304137
MN
2756 $calendartype = \core_calendar\type_factory::get_calendar_instance();
2757 return $calendartype->get_num_days_in_month($year, $month);
42d36497 2758}
2759
bbd3f2c4 2760/**
2761 * Calculate the position in the week of a specific calendar day
2762 *
9df12115
RT
2763 * @package core
2764 * @category time
bbd3f2c4 2765 * @param int $day The day of the date whose position in the week is sought
2766 * @param int $month The month of the date whose position in the week is sought
2767 * @param int $year The year of the date whose position in the week is sought
2768 * @return int
2769 */
8dc3f6cf 2770function dayofweek($day, $month, $year) {
da304137
MN
2771 $calendartype = \core_calendar\type_factory::get_calendar_instance();
2772 return $calendartype->get_weekday($year, $month, $day);
8dc3f6cf 2773}
2774
ac7af0da 2775// USER AUTHENTICATION AND LOGIN.
f9903ed0 2776
93f66983 2777/**
2778 * Returns full login url.
2779 *
93f66983 2780 * @return string login url
2781 */
999b54af 2782function get_login_url() {
93f66983 2783 global $CFG;
2784
999b54af 2785 $url = "$CFG->wwwroot/login/index.php";
93f66983 2786
999b54af
PS
2787 if (!empty($CFG->loginhttps)) {
2788 $url = str_replace('http:', 'https:', $url);
93f66983 2789 }
2790
2791 return $url;
2792}
2793
7cf1c7bd 2794/**
ec81373f 2795 * This function checks that the current user is logged in and has the
2796 * required privileges
2797 *
7cf1c7bd 2798 * This function checks that the current user is logged in, and optionally
ec81373f 2799 * whether they are allowed to be in a particular course and view a particular
2800 * course module.
2801 * If they are not logged in, then it redirects them to the site login unless
d2a9f7cc 2802 * $autologinguest is set and {@link $CFG}->autologinguests is set to 1 in which
ec81373f 2803 * case they are automatically logged in as guests.
2804 * If $courseid is given and the user is not enrolled in that course then the
2805 * user is redirected to the course enrolment page.
efb8c375 2806 * If $cm is given and the course module is hidden and the user is not a teacher
ec81373f 2807 * in the course then the user is redirected to the course home page.
7cf1c7bd 2808 *
191b267b 2809 * When $cm parameter specified, this function sets page layout to 'module'.
4f0c2d00 2810 * You need to change it manually later if some other layout needed.
191b267b 2811 *
f76249cc
PS
2812 * @package core_access
2813 * @category access
2814 *
33ebaf7c 2815 * @param mixed $courseorid id of the course or course object
0d0a8bf6 2816 * @param bool $autologinguest default true
bbd3f2c4 2817 * @param object $cm course module object
f4013c10 2818 * @param bool $setwantsurltome Define if we want to set $SESSION->wantsurl, defaults to
2819 * true. Used to avoid (=false) some scripts (file.php...) to set that variable,
2820 * in order to keep redirects working properly. MDL-14495
df997f84 2821 * @param bool $preventredirect set to true in scripts that can not redirect (CLI, rss feeds, etc.), throws exceptions
0d0a8bf6 2822 * @return mixed Void, exit, and die depending on path
ac7af0da
SH
2823 * @throws coding_exception
2824 * @throws require_login_exception
7cf1c7bd 2825 */
ac7af0da 2826function require_login($courseorid = null, $autologinguest = true, $cm = null, $setwantsurltome = true, $preventredirect = false) {
f0202ae9 2827 global $CFG, $SESSION, $USER, $PAGE, $SITE, $DB, $OUTPUT;
d8ba183c 2828
f22f1caf
PS
2829 // Must not redirect when byteserving already started.
2830 if (!empty($_SERVER['HTTP_RANGE'])) {
2831 $preventredirect = true;
2832 }
2833
ac7af0da 2834 // Setup global $COURSE, themes, language and locale.
c13a5e71 2835 if (!empty($courseorid)) {
2836 if (is_object($courseorid)) {
2837 $course = $courseorid;
2838 } else if ($courseorid == SITEID) {
2839 $course = clone($SITE);
2840 } else {
74df2951 2841 $course = $DB->get_record('course', array('id' => $courseorid), '*', MUST_EXIST);
c13a5e71 2842 }
95d28870 2843 if ($cm) {
df997f84
PS
2844 if ($cm->course != $course->id) {
2845 throw new coding_exception('course and cm parameters in require_login() call do not match!!');
2846 }
ac7af0da 2847 // Make sure we have a $cm from get_fast_modinfo as this contains activity access details.
47148151 2848 if (!($cm instanceof cm_info)) {
ac7af0da 2849 // Note: nearly all pages call get_fast_modinfo anyway and it does not make any
0d8b6a69 2850 // db queries so this is not really a performance concern, however it is obviously
2851 // better if you use get_fast_modinfo to get the cm before calling this.
2852 $modinfo = get_fast_modinfo($course);
2853 $cm = $modinfo->get_cm($cm->id);
2854 }
ac7af0da 2855 $PAGE->set_cm($cm, $course); // Set's up global $COURSE.
191b267b 2856 $PAGE->set_pagelayout('incourse');
95d28870 2857 } else {
ac7af0da 2858 $PAGE->set_course($course); // Set's up global $COURSE.
95d28870 2859 }
e88462a0 2860 } else {
ac7af0da 2861 // Do not touch global $COURSE via $PAGE->set_course(),
df997f84
PS
2862 // the reasons is we need to be able to call require_login() at any time!!
2863 $course = $SITE;
2864 if ($cm) {
2865 throw new coding_exception('cm parameter in require_login() requires valid course parameter!');
2866 }
c13a5e71 2867 }
be933850 2868
aa4a6566
SH
2869 // If this is an AJAX request and $setwantsurltome is true then we need to override it and set it to false.
2870 // Otherwise the AJAX request URL will be set to $SESSION->wantsurl and events such as self enrolment in the future
2871 // risk leading the user back to the AJAX request URL.
2872 if ($setwantsurltome && defined('AJAX_SCRIPT') && AJAX_SCRIPT) {
2873 $setwantsurltome = false;
2874 }
2875
12fc11e7 2876 // Redirect to the login page if session has expired, only with dbsessions enabled (MDL-35029) to maintain current behaviour.
8cd6d1aa 2877 if ((!isloggedin() or isguestuser()) && !empty($SESSION->has_timed_out) && !$preventredirect && !empty($CFG->dbsessions)) {
12fc11e7
DM
2878 if ($setwantsurltome) {
2879 $SESSION->wantsurl = qualified_me();
2880 }
2881 redirect(get_login_url());
2882 }
2883
ac7af0da 2884 // If the user is not even logged in yet then make sure they are.
083c3743 2885 if (!isloggedin()) {
df997f84 2886 if ($autologinguest and !empty($CFG->guestloginbutton) and !empty($CFG->autologinguests)) {
999b54af 2887 if (!$guest = get_complete_user_data('id', $CFG->siteguest)) {
ac7af0da 2888 // Misconfigured site guest, just redirect to login page.
999b54af 2889 redirect(get_login_url());
ac7af0da 2890 exit; // Never reached.
df997f84 2891 }
999b54af 2892 $lang = isset($SESSION->lang) ? $SESSION->lang : $CFG->lang;
0342fc36 2893 complete_user_login($guest);
d9e07264 2894 $USER->autologinguest = true;
999b54af 2895 $SESSION->lang = $lang;
8a33e371 2896 } else {
ac7af0da 2897 // NOTE: $USER->site check was obsoleted by session test cookie, $USER->confirmed test is in login/index.php.
999b54af
PS
2898 if ($preventredirect) {
2899 throw new require_login_exception('You are not logged in');
2900 }
2901
2902 if ($setwantsurltome) {
f0202ae9 2903 $SESSION->wantsurl = qualified_me();
999b54af
PS
2904 }
2905 if (!empty($_SERVER['HTTP_REFERER'])) {
2906 $SESSION->fromurl = $_SERVER['HTTP_REFERER'];
2907 }
2908 redirect(get_login_url());
ac7af0da 2909 exit; // Never reached.
8a33e371 2910 }
f9903ed0 2911 }
808a3baa 2912
ac7af0da 2913 // Loginas as redirection if needed.
d79d5ac2 2914 if ($course->id != SITEID and \core\session\manager::is_loggedinas()) {
f6f66b03 2915 if ($USER->loginascontext->contextlevel == CONTEXT_COURSE) {
df997f84 2916 if ($USER->loginascontext->instanceid != $course->id) {
3887fe4a 2917 print_error('loginasonecourse', '', $CFG->wwwroot.'/course/view.php?id='.$USER->loginascontext->instanceid);
5e623a33 2918 }
f6f66b03 2919 }
2920 }
2921
ac7af0da 2922 // Check whether the user should be changing password (but only if it is REALLY them).
d79d5ac2 2923 if (get_user_preferences('auth_forcepasswordchange') && !\core\session\manager::is_loggedinas()) {
21e2dcd9 2924 $userauth = get_auth_plugin($USER->auth);
df997f84 2925 if ($userauth->can_change_password() and !$preventredirect) {
af572078 2926 if ($setwantsurltome) {
f0202ae9 2927 $SESSION->wantsurl = qualified_me();
af572078 2928 }
80274abf 2929 if ($changeurl = $userauth->change_password_url()) {
ac7af0da 2930 // Use plugin custom url.
80274abf 2931 redirect($changeurl);
1437f0a5 2932 } else {
ac7af0da 2933 // Use moodle internal method.
9696bd89 2934 if (empty($CFG->loginhttps)) {
2935 redirect($CFG->wwwroot .'/login/change_password.php');
2936 } else {
ac7af0da 2937 $wwwroot = str_replace('http:', 'https:', $CFG->wwwroot);
9696bd89 2938 redirect($wwwroot .'/login/change_password.php');
2939 }
1437f0a5 2940 }
d35757eb 2941 } else {
a8ee7194 2942 print_error('nopasswordchangeforced', 'auth');
d35757eb 2943 }
2944 }
083c3743 2945
ac7af0da 2946 // Check that the user account is properly set up.
808a3baa 2947 if (user_not_fully_set_up($USER)) {
df997f84
PS
2948 if ($preventredirect) {
2949 throw new require_login_exception('User not fully set-up');
2950 }
af572078 2951 if ($setwantsurltome) {
f0202ae9 2952 $SESSION->wantsurl = qualified_me();
af572078 2953 }
b0ccd3fb 2954 redirect($CFG->wwwroot .'/user/edit.php?id='. $USER->id .'&amp;course='. SITEID);
808a3baa 2955 }
d8ba183c 2956
df997f84 2957 // Make sure the USER has a sesskey set up. Used for CSRF protection.
04280e85 2958 sesskey();
366dfa60 2959
ac7af0da 2960 // Do not bother admins with any formalities.
df997f84 2961 if (is_siteadmin()) {
ac7af0da 2962 // Set accesstime or the user will appear offline which messes up messaging.
1560760f 2963 user_accesstime_log($course->id);
df997f84
PS
2964 return;
2965 }
2966
ac7af0da 2967 // Check that the user has agreed to a site policy if there is one - do not test in case of admins.
b593d49d
PS
2968 if (!$USER->policyagreed and !is_siteadmin()) {
2969 if (!empty($CFG->sitepolicy) and !isguestuser()) {
2970 if ($preventredirect) {
2971 throw new require_login_exception('Policy not agreed');
2972 }
af572078 2973 if ($setwantsurltome) {
f0202ae9 2974 $SESSION->wantsurl = qualified_me();
af572078 2975 }
b593d49d
PS
2976 redirect($CFG->wwwroot .'/user/policy.php');
2977 } else if (!empty($CFG->sitepolicyguest) and isguestuser()) {
2978 if ($preventredirect) {
2979 throw new require_login_exception('Policy not agreed');
2980 }
af572078 2981 if ($setwantsurltome) {
f0202ae9 2982 $SESSION->wantsurl = qualified_me();
af572078 2983 }
027a1604 2984 redirect($CFG->wwwroot .'/user/policy.php');
027a1604 2985 }
1695b680 2986 }
2987
ac7af0da 2988 // Fetch the system context, the course context, and prefetch its child contexts.
b0c6dc1c
AG
2989 $sysctx = context_system::instance();
2990 $coursecontext = context_course::instance($course->id, MUST_EXIST);
df997f84 2991 if ($cm) {
b0c6dc1c 2992 $cmcontext = context_module::instance($cm->id, MUST_EXIST);
df997f84
PS
2993 } else {
2994 $cmcontext = null;
2995 }
21e2dcd9 2996
ac7af0da 2997 // If the site is currently under maintenance, then print a message.
4fe2250a 2998 if (!empty($CFG->maintenance_enabled) and !has_capability('moodle/site:config', $sysctx)) {
df997f84
PS
2999 if ($preventredirect) {
3000 throw new require_login_exception('Maintenance in progress');
3001 }
3002
4fe2250a 3003 print_maintenance_message();
027a1604 3004 }
3005
ac7af0da 3006 // Make sure the course itself is not hidden.
df997f84 3007 if ($course->id == SITEID) {
ac7af0da 3008 // Frontpage can not be hidden.
df997f84 3009 } else {
f5c1e621 3010 if (is_role_switched($course->id)) {
ac7af0da 3011 // When switching roles ignore the hidden flag - user had to be in course to do the switch.
df997f84
PS
3012 } else {
3013 if (!$course->visible and !has_capability('moodle/course:viewhiddencourses', $coursecontext)) {
ac7af0da
SH
3014 // Originally there was also test of parent category visibility, BUT is was very slow in complex queries
3015 // involving "my courses" now it is also possible to simply hide all courses user is not enrolled in :-).
df997f84
PS
3016 if ($preventredirect) {
3017 throw new require_login_exception('Course is hidden');
3018 }
ac7af0da
SH
3019 // We need to override the navigation URL as the course won't have been added to the navigation and thus
3020 // the navigation will mess up when trying to find it.
a0a39b0d 3021 navigation_node::override_active_url(new moodle_url('/'));
df997f84
PS
3022 notice(get_string('coursehidden'), $CFG->wwwroot .'/');
3023 }
3024 }
3025 }
3026
ac7af0da 3027 // Is the user enrolled?
df997f84 3028 if ($course->id == SITEID) {
ac7af0da 3029 // Everybody is enrolled on the frontpage.
df997f84 3030 } else {
d79d5ac2 3031 if (\core\session\manager::is_loggedinas()) {
ac7af0da 3032 // Make sure the REAL person can access this course first.
d79d5ac2 3033 $realuser = \core\session\manager::get_realuser();
ac7af0da
SH
3034 if (!is_enrolled($coursecontext, $realuser->id, '', true) and
3035 !is_viewing($coursecontext, $realuser->id) and !is_siteadmin($realuser->id)) {
df997f84
PS
3036 if ($preventredirect) {
3037 throw new require_login_exception('Invalid course login-as access');
3038 }
3039 echo $OUTPUT->header();
3040 notice(get_string('studentnotallowed', '', fullname($USER, true)), $CFG->wwwroot .'/');
3041 }
3042 }
3043
df997f84
PS
3044 $access = false;
3045
dbd7282c 3046 if (is_role_switched($course->id)) {
ac7af0da 3047