mahara.php 84.1 KB
Newer Older
1
2
<?php
/**
Francois Marier's avatar
Francois Marier committed
3
 * Mahara: Electronic portfolio, weblog, resume builder and social networking
4
5
 * Copyright (C) 2006-2009 Catalyst IT Ltd and others; see:
 *                         http://wiki.mahara.org/Contributors
6
 *
Francois Marier's avatar
Francois Marier committed
7
8
9
10
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
11
 *
Francois Marier's avatar
Francois Marier committed
12
13
14
15
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
16
 *
Francois Marier's avatar
Francois Marier committed
17
18
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
19
20
21
 *
 * @package    mahara
 * @subpackage core
22
 * @author     Catalyst IT Ltd
23
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL
24
 * @copyright  (C) 2006-2009 Catalyst IT Ltd http://catalyst.net.nz
25
 * @copyright  (C) portions from Moodle, (C) Martin Dougiamas http://dougiamas.com
26
27
 */

28
defined('INTERNAL') || die();
29

30
31
32
33
34
35
36
/** 
 * work around silly php settings
 * and broken setup stuff about the install
 * and raise a warning/fail depending on severity
 */
function ensure_sanity() {

37
    // PHP version
38
39
40
    $phpversionrequired = '5.2.0';
    if (version_compare(phpversion(), $phpversionrequired) < 0) {
        throw new ConfigSanityException(get_string('phpversion', 'error', $phpversionrequired));
41
42
43
44
45
46
    }

    // Various required extensions
    if (!extension_loaded('json')) {
        throw new ConfigSanityException(get_string('jsonextensionnotloaded', 'error'));
    }
47
48
49
50
51
52
    switch (get_config('dbtype')) {
    case 'postgres8':
        if (!extension_loaded('pgsql')) {
            throw new ConfigSanityException(get_string('pgsqldbextensionnotloaded', 'error'));
        }
        break;
53
    case 'mysql5':
54
55
56
57
58
59
        if (!extension_loaded('mysql')) {
            throw new ConfigSanityException(get_string('mysqldbextensionnotloaded', 'error'));
        }
        break;
    default:
        throw new ConfigSanityException(get_string('unknowndbtype', 'error'));
60
    }
61
62
63
    if (!extension_loaded('xml')) {
        throw new ConfigSanityException(get_string('xmlextensionnotloaded', 'error', 'xml'));
    }
64
    if (!extension_loaded('libxml')) {
65
        throw new ConfigSanityException(get_string('xmlextensionnotloaded', 'error', 'libxml'));
66
67
68
69
70
71
72
73
    }
    if (!extension_loaded('gd')) {
        throw new ConfigSanityException(get_string('gdextensionnotloaded', 'error'));
    }
    if (!extension_loaded('session')) {
        throw new ConfigSanityException(get_string('sessionextensionnotloaded', 'error'));
    }

74
75
76
    if(!extension_loaded('curl')) {
        throw new ConfigSanityException(get_string('curllibrarynotinstalled', 'error'));
    }
77
78
79
    if (!extension_loaded('dom')) {
        throw new ConfigSanityException(get_string('domextensionnotloaded', 'error'));
    }
80

81
82
83
84
85
86
    //Check for freetype in the gd extension
    $gd_info = gd_info();
    if (!$gd_info['FreeType Support']) {
        throw new ConfigSanityException(get_string('gdfreetypenotloaded', 'error'));
    }

87
88
    // register globals workaround
    if (ini_get_bool('register_globals')) {
89
        log_environ(get_string('registerglobals', 'error'));
90
        $massivearray = array_keys(array_merge($_POST, $_GET, $_COOKIE, $_SERVER, $_REQUEST, $_FILES));
91
92
93
94
95
96
        foreach ($massivearray as $tounset) {
            unset($GLOBALS[$tounset]);
        }
    }

    // magic_quotes_gpc workaround
97
    if (!defined('CRON') && ini_get_bool('magic_quotes_gpc')) {
98
        log_environ(get_string('magicquotesgpc', 'error'));
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
        function stripslashes_deep($value) {
            $value = is_array($value) ?
                array_map('stripslashes_deep', $value) :
                stripslashes($value);
            return $value;
        }
        $_POST = array_map('stripslashes_deep', $_POST);
        $_GET = array_map('stripslashes_deep', $_GET);
        $_COOKIE = array_map('stripslashes_deep', $_COOKIE);
        $_REQUEST = array_map('stripslashes_deep', $_REQUEST);

        $servervars = array('REQUEST_URI','QUERY_STRING','HTTP_REFERER','PATH_INFO','PHP_SELF','PATH_TRANSLATED');
        foreach ($servervars as $tocheck) {
            if (array_key_exists($tocheck,$_SERVER) && !empty($_SERVER[$tocheck])) {
                $_SERVER[$tocheck] = stripslashes($_SERVER[$tocheck]);
            }
        }
    }

118
    if (ini_get_bool('magic_quotes_runtime')) {
119
120
121
122
123
124
125
126
127
        // Turn of magic_quotes_runtime. Anyone with this on deserves a slap in the face
        set_magic_quotes_runtime(0);
        log_environ(get_string('magicquotesruntime', 'error'));
    }

    if (ini_get_bool('magic_quotes_sybase')) {
        // See above comment re. magic_quotes_runtime
        @ini_set('magic_quotes_sybase', 0);
        log_environ(get_string('magicquotessybase', 'error'));
128
129
    }

130
131
132
    if (ini_get_bool('safe_mode')) {
        // We don't run with safe mode
        throw new ConfigSanityException(get_string('safemodeon', 'error'));
133
134
    }

135
136
137
138
139
    if ('0' === ini_get('apc.stat') or 'off' === ini_get('apc.stat')) {
        // We don't run with apc.stat=0 (see https://bugs.launchpad.net/mahara/+bug/548333)
        throw new ConfigSanityException(get_string('apcstatoff', 'error'));
    }

140
141
142
143
144
145
146
    // Other things that might be worth checking:
    //    memory limit
    //    file_uploads (off|on)
    //    upload_max_filesize
    //    allow_url_fopen (only if we use this)
    //

147
    // dataroot inside document root.
148
149
    if (strpos(get_config('dataroot'), get_config('docroot')) !== false) {
        throw new ConfigSanityException(get_string('datarootinsidedocroot', 'error'));
150
151
    }

152
153
    // dataroot not writable..
    if (!check_dir_exists(get_config('dataroot')) || !is_writable(get_config('dataroot'))) {
154
        throw new ConfigSanityException(get_string('datarootnotwritable', 'error', get_config('dataroot')));
155
    }
156

157
158
159
    if (
        !check_dir_exists(get_config('dataroot') . 'smarty/compile') ||
        !check_dir_exists(get_config('dataroot') . 'smarty/cache') ||
160
        !check_dir_exists(get_config('dataroot') . 'sessions') ||
161
        !check_dir_exists(get_config('dataroot') . 'temp') ||
162
        !check_dir_exists(get_config('dataroot') . 'langpacks') ||
163
164
165
        !check_dir_exists(get_config('dataroot') . 'htmlpurifier') ||
        !check_dir_exists(get_config('dataroot') . 'log') ||
        !check_dir_exists(get_config('dataroot') . 'images')) {
166
167
        throw new ConfigSanityException(get_string('couldnotmakedatadirectories', 'error'));
    }
168

169
    raise_memory_limit('128M');
170
171
}

172
173
174
175
176
177
178
179
180
181
182
/**
 * Check sanity of things that we only check at installation time - not on 
 * every request, like ensure_sanity() does
 */
function ensure_install_sanity() {
    // Must must must be a UTF8 database!
    if (!db_is_utf8()) {
        throw new ConfigSanityException(get_string('dbnotutf8', 'error'));
    }
}

183
184
185
186
187
188
189
190
191
192
193
194
function ensure_upgrade_sanity() {
    // Check column collation is equal to the default
    if (is_mysql()) {
        require_once('ddl.php');
        if (table_exists(new XMLDBTable('event_type'))) {
            if (!column_collation_is_default('event_type', 'name')) {
                throw new ConfigSanityException(get_string('dbcollationmismatch', 'admin'));
            }
        }
    }
}

195
196
197
198
199
/**
 * Check to see if the internal plugins are installed. Die if they are not.
 */
function ensure_internal_plugins_exist() {
    // Internal things installed
200
    if (get_config('installed')) {
201
202
203
204
205
206
207
208
        foreach (plugin_types() as $type) {
            if (!record_exists($type . '_installed', 'name', 'internal')) {
                throw new ConfigSanityException(get_string($type . 'notinstalled'));
            }
        }
    }
}

209
function get_string($identifier, $section='mahara') {
210
211
212
213
214

    $variables = func_get_args();
    if (count($variables) > 2) { // we have some stuff we need to sprintf
        array_shift($variables);
        array_shift($variables); //shift off the first two.
215
216
    }
    else {
217
218
219
        $variables = array();
    }
    
220
221
222
    return get_string_location($identifier, $section, $variables);
}

223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
function get_string_from_language($lang, $identifier, $section='mahara') {

    $variables = func_get_args();
    if (count($variables) > 3) { // we have some stuff we need to sprintf
        array_shift($variables);
        array_shift($variables);
        array_shift($variables); //shift off the first three.
    }
    else {
        $variables = array();
    }
    
    return get_string_location($identifier, $section, $variables, 'format_langstring', $lang);
}

238
239
240
241
242
243
244
245
246
function get_helpfile($plugintype, $pluginname, $form, $element, $page=null, $section=null) {
    if ($langfile = get_helpfile_location($plugintype, $pluginname, $form, $element, $page, $section)) {
        return file_get_contents($langfile);
    }
    return false;
}

function get_helpfile_location($plugintype, $pluginname, $form, $element, $page=null, $section=null) {

247
    $subdir = 'help/';
248
249

    if ($page) {
250
251
        $pagebits = split('-', $page);
        $file = array_pop($pagebits) . '.html';
252
        if ($plugintype != 'core') {
253
            $subdir .= 'pages/' . join('/', $pagebits) . '/';
254
255
        }
        else {
256
            $subdir .= 'pages/' . $pluginname . '/' . join('/', $pagebits) . '/';
257
        } 
258
259
    }
    else if ($section) {
260
261
        $subdir .= 'sections/';
        $file = $section . '.html';
262
263
    }
    else if (!empty($form) && !empty($element)) {
264
265
        $subdir .= 'forms/';
        $file = $form . '.' . $element . '.html';
266
267
    }
    else if (!empty($form) && empty($element)) {
268
269
        $subdir .= 'forms/';
        $file = $form . '.html';
270
271
272
273
274
275
276
277
278
279
280
281
282
283
    }
    else {
        return false;
    }

    // now we have to try and locate the help file
    $lang = current_language();
    if ($lang == 'en.utf8') {
        $trieden = true;
    }
    else {
        $trieden = false;
    }

284
    //try the local settings
285
286
287
288
289
290
291
    $langfile = get_config('docroot') . 'local/lang/' . $lang . '/' . $subdir;
    if ($plugintype != 'core') {
        $langfile .= $plugintype . '.' . $pluginname . '.' . $file;
    }
    else {
        $langfile .= $file;
    }
292
293
294
295
    if (is_readable($langfile)) {
        return $langfile;
    }

296
297
298
299
300
301
302
    if ($plugintype != 'core') {
        $location = $plugintype . '/' . $pluginname . '/lang/';
    }
    else {
        $location = 'lang/';
    }

303
    // try the current language
304
    $langfile = get_language_root() . $location . $lang . '/' . $subdir . $file;
305
306
307
308
309
310
    if (is_readable($langfile)) {
        return $langfile;
    }

    // if it's not found, try the parent language if there is one...
    if (empty($data) && empty($trieden)) {
311
        $langfile = get_language_root($lang) . 'lang/' . $lang . '/langconfig.php';
312
313
314
315
        if ($parentlang = get_string_from_file('parentlanguage', $langfile)) {
            if ($parentlang == 'en.utf8') {
                $trieden = true;
            }
316
            $langfile = get_language_root($parentlang) . $location . $parentlang . '/' . $subdir . $file;
317
318
319
320
321
322
323
324
            if (is_readable($langfile)) {
                return $langfile;
            }
        }
    }

    // if it's STILL not found, and we haven't already tried english ...
    if (empty($data) && empty($trieden)) {
325
        $langfile = get_language_root('en.utf8') . $location . 'en.utf8/' . $subdir . $file;
326
327
328
329
330
331
332
        if (is_readable($langfile)) {
            return $langfile;
        }
    }
    return false;
}

333
334
335
336
337
// get a string without sprintfing it.
function get_raw_string($identifier, $section='mahara') {
    // For a raw string we don't want to format any arguments using
    // sprintf, so the replace function passed to get_string_location
    // should just return the first argument and ignore the second.
338
    return get_string_location($identifier, $section, array(), 'raw_langstring');
339
340
341
342
343
344
345
346
347
348
349
350
351
352
}


/**
 * This function gets a language string identified by $identifier from
 * an appropriate location, and formats the string and any arguments
 * in $variables using the function $replacefunc.
 *
 * @param string   $identifier
 * @param string   $section
 * @param array    $variables
 * @param function $replacefunc
 * @return string
 */
353
function get_string_location($identifier, $section, $variables, $replacefunc='format_langstring', $lang='') {
354

355
    $langconfigstrs = array('parentlanguage', 'thislanguage');
356

357
358
359
360
    if ($section == 'mahara' &&
        (in_array($identifier, $langconfigstrs)
         || strpos($identifier, 'strftime') === 0
         || strpos($identifier, 'strfday')  === 0)) {
361
362
363
        $section = 'langconfig';
    }

364
365
366
    if (empty($lang)) {
        $lang = current_language();
    }
367
368

    // Define the locations of language strings for this section
369
    $langstringroot = get_language_root($lang);
370
    $langdirectory  = ''; // The directory in which the language file for this string should ideally reside, if the language has implemented it
371
    
372
    if (false === strpos($section, '.')) {
373
        $langdirectory = 'lang/';
374
375
376
    }
    else {
        $extras = plugin_types(); // more later..
377
        foreach ($extras as $tocheck) {
378
            if (strpos($section, $tocheck . '.') === 0) {
Nigel McNie's avatar
Nigel McNie committed
379
                $pluginname = substr($section ,strlen($tocheck) + 1);
380
381
382
                if ($tocheck == 'blocktype' && 
                    strpos($pluginname, '/') !== false) { // it belongs to an artefact plugin
                    $bits = explode('/', $pluginname);
383
                    $langdirectory = 'artefact/' . $bits[0] . '/blocktype/' . $bits[1] . '/lang/';
384
                    $section = 'blocktype.' . $bits[1];
385
386
                }
                else {
387
                    $langdirectory = $tocheck . '/' . $pluginname . '/lang/';
388
                }
389
390
391
            }
        }
    }
392

393
    // First check all the normal locations for the string in the current language
394
395
    $result = get_string_local($langstringroot . $langdirectory, $lang . '/' . $section . '.php', $identifier);
    if ($result !== false) {
396
        return $replacefunc($result, $variables);
397
398
399
400
401
    }

    // If the preferred language was English (utf8) we can abort now
    // saving some checks beacuse it's the only "root" lang
    if ($lang == 'en.utf8') {
402
        return '[[' . $identifier . '/' . $section . ']]';
403
404
405
    }

    // Is a parent language defined?  If so, try to find this string in a parent language file
406
407
408
    $langfile = $langstringroot . 'lang/' . $lang . '/langconfig.php';
    if (is_readable($langfile)) {
        if ($parentlang = get_string_from_file('parentlanguage', $langfile)) {
409
410
            $result = get_string_local(get_language_root($parentlang) . 'lang/', $parentlang . '/' . $section . '.php', $identifier);
            if ($result !== false) {
411
                return $replacefunc($result, $variables);
412
413
414
415
416
            }
        }
    }

    /// Our only remaining option is to try English
417
418
    $result = get_string_local(get_config('docroot') . $langdirectory, 'en.utf8/' . $section . '.php', $identifier);
    if ($result !== false) {
419
        return $replacefunc($result, $variables);
420
421
    }

422
    return '[[' . $identifier . '/' . $section . ']]';  // Last resort
423
}
424
425


426
427
428
429
430
431
432
433
/**
 * Get string from a file, checking the appropriate local customisation directory first
 *
 */
function get_string_local($langpath, $langfile, $identifier) {
    foreach (array(get_config('docroot') . 'local/lang/', $langpath) as $dir) {
        $file = $dir . $langfile;
        if (is_readable($file)) {
434
435
            $result = get_string_from_file($identifier, $file);
            if ($result !== false) {
436
437
438
439
440
441
442
443
                return $result;
            }
        }
    }
    return false;
}


444
445
446
447
448
/**
 * Return a list of available languages
 *
 */
function get_languages() {
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
    static $langs = array();

    if (!$langs) {
        foreach (language_get_searchpaths() as $searchpath) {
            $langbase = $searchpath . 'lang/';
            if ($langdir = @opendir($langbase)) {
                while (false !== ($subdir = readdir($langdir))) {
                    if (preg_match('/\.utf8$/', $subdir) && is_dir($langbase . $subdir)) {
                        $langfile = $langbase . $subdir . '/langconfig.php';
                        if (is_readable($langfile)) {
                            if ($langname = get_string_from_file('thislanguage', $langfile)) {
                                $langs[$subdir] = $langname;
                            }
                        }
                    }
464
                }
465
466
467
468
                closedir($langdir);
            }
            else {
                log_warn('Unable to read language directory ' . $langbase);
469
470
471
            }
        }
    }
472

473
474
475
    return $langs;
}

476
477
478
/**
 * Returns whether the given language is installed/available for use
 */
479
function language_installed($lang) {
480
481
482
483
484
485
    foreach (language_get_searchpaths() as $searchpath) {
        if (is_readable($searchpath . 'lang/' . $lang . '/langconfig.php')) {
            return true;
        }
    }
    return false;
486
487
}

488
489
490
491
492
493
494
495
496
/**
 * Returns a list of directories in which to search for language packs.
 *
 * This is influenced by the configuration variable 'langpacksearchpaths'
 */
function language_get_searchpaths() {
    static $searchpaths = array();

    if (!$searchpaths) {
497
498
499
500
        // Construct the search path
        $docrootpath = array(get_config('docroot'));

        // Paths to language files in dataroot
501
        $datarootpaths = (array)glob(get_config('dataroot') . 'langpacks/*', GLOB_MARK | GLOB_ONLYDIR);
502
503
504
505
506
507
508
509
510
511

        // langpacksearchpaths configuration variable - for experts :)
        $lpsearchpaths = (array)get_config('langpacksearchpaths');
        $langpacksearchpaths = array();
        foreach ($lpsearchpaths as $path) {
            if (is_dir($path)) {
                $langpacksearchpaths[] = (substr($path, -1) == '/') ? $path : "$path/";
            }
            else {
                log_warn("Path in langpacksearchpaths is not a directory: $path");
512
            }
513
        }
514
515

        $searchpaths = array_merge($docrootpath, $datarootpaths, $langpacksearchpaths);
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
    }

    return $searchpaths;
}

/**
 * Get the directory in which the specified language pack resides.
 *
 * Defaults to getting the directory for the current_language() - i.e. the 
 * language the user is using
 *
 * Returns null if the language can't be found
 *
 * @param string $language The language to look for
 */
function get_language_root($language=null) {
    static $language_root_cache = array();

    if (!isset($language_root_cache[$language])) {
        if ($language == null) {
            $language = current_language();
        }

        foreach (language_get_searchpaths() as $path) {
            if (is_dir("$path/lang/$language")) {
                return $language_root_cache[$language] = $path;
            }
        }

        // Oh noes, can't be found
        $language_root_cache[$language] = null;

    }

    return $language_root_cache[$language];
}

553
/**
554
 * Return a list of all available themes.
555
 * @return array subdir => name
556
 */
557
function get_all_themes() {
558
559
    static $themes = null;

560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
    if (is_null($themes)) {
        $themes = array();
        $themelist = get_all_theme_objects();
        foreach ($themelist AS $subdir => $theme) {
            $themes[$subdir] = isset($theme->displayname) ? $theme->displayname : $subdir;
        }
    }

    return $themes;
}

/**
 * Return a list of themes available to this user
 * If the user is a member of any institutions, only themes available to
 * those institutions are returned; or
 * If a user is not a member of any institution, all themes not marked as
 * institution specific are returned.
 * @return array subdir => name
 */
579
function get_user_accessible_themes() {
580
581
582
583
584
585
    global $USER;

    $themes = array();
    if ($institutions = $USER->get('institutions')) {
        // Get themes for all of this users institutions
        foreach ($institutions AS $i) {
586
            $themes = array_merge($themes, get_institution_themes($i->institution));
587
588
        }
    }
589
590
591
    else {
        $themelist = get_all_theme_objects();
        foreach ($themelist AS $subdir => $theme) {
592
            if (!isset($theme->institutions) || !is_array($theme->institutions)) {
593
594
595
596
597
                $themes[$subdir] = isset($theme->displayname) ? $theme->displayname : $subdir;
            }
        }

    }
598
    $themes = array_merge(array('sitedefault' => '- ' . get_string('sitedefault', 'admin') . ' (' . $themes[get_config('theme')] . ') -'), $themes);
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
    return $themes;
}

/**
 * Return a list of themes available to the specified institution
 * @param string institution the name of the institution to load themes for
 * @return array subdir => name
 * @throws SystemException if unable to read the theme directory
 */
function get_institution_themes($institution) {
    static $institutionthemes = array();
    if (!isset($institutionthemes[$institution])) {
        $themes = get_all_theme_objects();
        $r = array();
        foreach ($themes AS $subdir => $theme) {
614
            if (empty($theme->institutions) || !is_array($theme->institutions) || in_array($institution, $theme->institutions)) {
615
                $r[$subdir] = isset($theme->displayname) ? $theme->displayname : $subdir;
616
617
            }
        }
618
        $institutionthemes[$institution] = $r;
619
620
    }

621
622
623
624
625
626
627
628
629
630
    return $institutionthemes[$institution];
}

/**
 * Return a list of all themes available on the system
 * @return array An array of theme objects
 * @throws SystemException if unable to read the theme directory
 */
function get_all_theme_objects() {
    static $themes = null;
631

632
633
634
635
636
637
638
639
    if (is_null($themes)) {
        $themes = array();
        $themebase = get_config('docroot') . 'theme/';
        if (!$themedir = opendir($themebase)) {
            throw new SystemException('Unable to read theme directory '.$themebase);
        }
        while (false !== ($subdir = readdir($themedir))) {
            if ($subdir != "." && $subdir != ".." && is_dir($themebase . $subdir)) {
640
641
642
643
644
645
646
647
648
649
                // is the theme directory name valid?
                if (!Theme::name_is_valid($subdir)) {
                    log_warn(get_string('themenameinvalid', 'error', $subdir));
                } else {
                    $config_path = $themebase . $subdir . '/themeconfig.php';
                    if (is_readable($config_path)) {
                        require($config_path);
                        if (empty($theme->disabled) || !$theme->disabled) {
                            $themes[$subdir] = $theme;
                        }
650
                    }
651
                }
652
            }
653
        }
654
        closedir($themedir);
655
        asort($themes);
656
    }
657

658
659
660
661
    return $themes;
}


662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
/**
 * This function is only used from {@link get_string()}.
 *
 * @internal Only used from get_string, not meant to be public API
 * @param string $identifier ?
 * @param string $langfile ?
 * @param string $destination ?
 * @return string|false ?
 * @staticvar array $strings Localized strings
 * @access private
 * @todo Finish documenting this function.
 */
function get_string_from_file($identifier, $langfile) {

    static $strings;    // Keep the strings cached in memory.

    if (empty($strings[$langfile])) {
        $string = array();
        include ($langfile);
        $strings[$langfile] = $string;
    } else {
        $string = &$strings[$langfile];
    }

    if (!isset ($string[$identifier])) {
        return false;
    }

    return $string[$identifier];
}

/**
 * This function makes the return value of ini_get consistent if you are
 * setting server directives through the .htaccess file in apache.
 * Current behavior for value set from php.ini On = 1, Off = [blank]
 * Current behavior for value set from .htaccess On = On, Off = Off
 * Contributed by jdell @ unr.edu
 *
700
 * @param string $ini_get_arg setting to look for
701
702
703
704
705
706
707
708
709
710
711
 * @return bool
 */
function ini_get_bool($ini_get_arg) {
    $temp = ini_get($ini_get_arg);

    if ($temp == '1' or strtolower($temp) == 'on') {
        return true;
    }
    return false;
}

712
713
714
715
716
717
718
719
/**
 * This function loads up the basic $CFG
 * from the database table
 * note that it doesn't load plugin config
 * as not every page needs them
 * @return boolean false if the assignment fails (generally if the databse is not installed)
 */
function load_config() {
720
721
722
723
724
725
726
727
728
729
730
731
   global $CFG;
   global $OVERRIDDEN;    // array containing the database config fields overridden by $CFG

   $dbconfig = get_records_array('config', '', '', '', 'field, value');

   foreach ($dbconfig as $cfg) {
       if (isset($CFG->{$cfg->field})) {
           $OVERRIDDEN[] = $cfg->field;
       } else {
           $CFG->{$cfg->field} = $cfg->value;
       }
   }
732

733
   return true;
734
735
736
}

/**
737
738
739
740
741
742
 * This function returns a value from $CFG
 * or null if it is not found
 * 
 * @param string $key config setting to look for 
 * @return mixed
 */
743
744
function get_config($key) {
    global $CFG;
745
    if (isset($CFG->$key)) {
746
747
748
749
750
        return $CFG->$key;
    }
    return null;
}

751
752
753
754
755
756
757
758
759

/**
 * This function sets a config variable
 * both in $CFG and in the database
 *
 * @param string $key config field to set
 * @param string $value config value
 */
function set_config($key, $value) {
760
761
    global $CFG;

762
    db_ignore_sql_exceptions(true);
763
764
    if (get_record('config', 'field', $key)) {
        if (set_field('config', 'value', $value, 'field', $key)) {
Penny Leach's avatar
Penny Leach committed
765
766
767
768
769
770
771
            $status = true;
        }
    } 
    else {
        $config = new StdClass;
        $config->field = $key;
        $config->value = $value;
772
        $status = insert_record('config', $config);
Penny Leach's avatar
Penny Leach committed
773
    }
774
    db_ignore_sql_exceptions(false);
Penny Leach's avatar
Penny Leach committed
775
776

    if (!empty($status)) {
777
778
779
        $CFG->{$key} = $value;
        return true;
    }
Penny Leach's avatar
Penny Leach committed
780

781
782
783
784
785
786
787
788
789
790
791
792
793
794
    return false;
}

/**
 * This function returns a value for $CFG for a plugin
 * or null if it is not found
 * note that it may go and look in the database
 *
 * @param string $plugintype eg artefact
 * @param string $pluginname eg blog
 * @param string $key the config setting to look for
 */
function get_config_plugin($plugintype, $pluginname, $key) {
    global $CFG;
795

796
797
    // Suppress NOTICE with @ in case $key is not yet cached
    @$value = $CFG->plugin->{$plugintype}->{$pluginname}->{$key};
798
    if (isset($value)) {
799
800
801
802
        return $value;
    }

    $records = get_records_array($plugintype . '_config', 'plugin', $pluginname, 'field', 'field, value');
803
    if (!empty($records)) {
804
805
        foreach($records as $record) {
            $CFG->plugin->{$plugintype}->{$pluginname}->{$record->field} = $record->value;
806
            if ($record->field == $key) {
807
808
809
                $value = $record->value;
            }
        }
810
811
    }

812
813
814
    return $value;
}

Penny Leach's avatar
Penny Leach committed
815
function set_config_plugin($plugintype, $pluginname, $key, $value) {
816
    global $CFG;
817
    $table = $plugintype . '_config';
Penny Leach's avatar
Penny Leach committed
818

819
820
821
    if (false !== get_field($table, 'value', 'plugin', $pluginname, 'field', $key)) {
        //if (set_field($table, 'value', $key, 'plugin', $pluginname, 'field', $value)) {
        if (set_field($table, 'value', $value, 'plugin', $pluginname, 'field', $key)) {
Penny Leach's avatar
Penny Leach committed
822
823
824
825
826
827
828
829
            $status = true;
        }
    }
    else {
        $pconfig = new StdClass;
        $pconfig->plugin = $pluginname;
        $pconfig->field  = $key;
        $pconfig->value  = $value;
830
        $status = insert_record($table, $pconfig);
Penny Leach's avatar
Penny Leach committed
831
832
833
834
835
836
837
838
    }
    if ($status) {
        $CFG->plugin->{$plugintype}->{$pluginname}->{$key} = $value;
        return true;
    }
    return false;
}

839
840
841
842
843
844
845
846
847
848
/**
 * This function returns a value for $CFG for a plugin instance
 * or null if it is not found. Initially this is interesting only 
 * for multiauth. Note that it may go and look in the database
 *
 * @param string $plugintype   E.g. auth
 * @param string $pluginname   E.g. internal
 * @param string $pluginid     Instance id
 * @param string $key          The config setting to look for
 */
849
function get_config_plugin_instance($plugintype, $pluginid, $key) {
850
851
852
853
854
855
    global $CFG;

    // Must be unlikely to exist as a config option for any plugin
    $instance = '_i_n_s_t'.$pluginid;

    // Suppress NOTICE with @ in case $key is not yet cached
856
    @$value = $CFG->plugin->{$plugintype}->{$instance}->{$key};
857
    if (isset($value)) {
858
859
860
        return $value;
    }

861
    $records = get_records_array($plugintype . '_instance_config', 'instance', $pluginid, 'field', 'field, value');
862
    if (!empty($records)) {
863
        foreach($records as $record) {
864
            $CFG->plugin->{$plugintype}->{$instance}->{$record->field} = $record->value;
865
            if ($record->field == $key) {
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
                $value = $record->value;
            }
        }
    }

    return $value;
}

/**
 * This function returns a value for $CFG for a plugin instance
 * or null if it is not found. Initially this is interesting only 
 * for multiauth. Note that it may go and look in the database
 *
 * @param string $plugintype   E.g. auth
 * @param string $pluginname   E.g. internal
 * @param string $pluginid     Instance id
 * @param string $key          The config setting to look for
 */
function set_config_plugin_instance($plugintype, $pluginname, $pluginid, $key, $value) {
    global $CFG;
    $table = $plugintype . '_instance_config';

    if (false !== get_field($table, 'value', 'instance', $pluginid, 'field', $key)) {
        if (set_field($table, 'value', $value, 'instance', $pluginid, 'field', $key)) {
            $status = true;
        }
    }
    else {
        $pconfig = new StdClass;
        $pconfig->instance = $pluginid;
        $pconfig->field  = $key;
        $pconfig->value  = $value;
        $status = insert_record($table, $pconfig);
    }
    if ($status) {
        // Must be unlikely to exist as a config option for any plugin
        $instance = '_i_n_s_t'.$pluginid;
        $CFG->plugin->{$plugintype}->{$pluginname}->{$instance}->{$key} = $value;
        return true;
    }
    return false;
}

909
/**
910
911
912
913
914
 * This function prints an array or object
 * wrapped inside <pre></pre>
 * 
 * @param $mixed value to print
 */
915
916
917
918
919
920
function print_object($mixed) {
    echo '<pre>';
    print_r($mixed);
    echo '</pre>';
}

921
/**
922
923
924
 * This function returns the current 
 * language to use, either for a given user
 * or sitewide, or the default
925
926
 *
 * param @string $reset If passed, reset the current language to this
927
928
929
 * 
 * @return string
 */
930
function current_language($reset=null) {
931
    global $USER, $CFG, $SESSION;
932
933
934

    static $lang;

935
936
937
938
    if (!empty($reset)) {
        $lang = $reset;  // Set the language for this request
    }

939
940
941
942
    if (!empty($lang)) {
        return $lang;
    }

943
    if ($USER instanceof User) {
944
945
946
947
948
949
950
        $userlang = $USER->get_account_preference('lang');
        if ($userlang !== null && $userlang != 'default') {
            if (language_installed($userlang)) {
                $lang = $userlang;
            }
            else {
                $USER->set_account_preference('lang', 'default');
951
            }
952
        }
953
    }
954

955
956
957
958
    if (empty($lang) && is_a($SESSION, 'Session')) {
        $sesslang = $SESSION->get('lang');
        if (!empty($sesslang) && $sesslang != 'default') {
            $lang = $sesslang;
959
        }
960
    }
961

962
963
964
965
966
967
968
969
970
    if (empty($lang)) {
        $lang = !empty($CFG->lang) ? $CFG->lang : 'en.utf8';
    }

    // Set locale.  We are probably being called from get_string_location.
    // $lang had better be non-empty, or it will call us again.
    if ($args = split(',', get_string_location('locales', 'langconfig', array(), 'raw_langstring', $lang))) {
        array_unshift($args, LC_ALL);
        call_user_func_array('setlocale', $args);
971
    }
972
973

    return $lang;
974
975
}

976
/**
977
978
979
980
981
982
 * Helper function to sprintf language strings
 * with a variable number of arguments
 * 
 * @param string $string raw string to use
 * @param array $args arguments to sprintf
 */
983
984
985
986
function format_langstring($string,$args) {
    return call_user_func_array('sprintf',array_merge(array($string),$args));
}

987
988
989
990
function raw_langstring($string) {
    return $string;
}

991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
/**
 * Helper function to figure out whether an array is an array or a hash
 * @param array $array array to check
 * @return bool true if the array is a hash
 */
function is_hash($array) {
    if (!is_array($array)) {
        return false;
    }
    $diff = array_diff_assoc($array,array_values($array));
    return !empty($diff);
}

1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
/**
 * Function to check if a directory exists and optionally create it.
 *
 * @param string absolute directory path
 * @param boolean create directory if does not exist
 * @param boolean create directory recursively
 *
 * @return boolean true if directory exists or created
 */
function check_dir_exists($dir, $create=true, $recursive=true) {

    $status = true;

    if(!is_dir($dir)) {
        if (!$create) {
            $status = false;
        } else {
1021
1022
1023
            $mask = umask(0000);
            $status = @mkdir($dir, get_config('directorypermissions'), true);
            umask($mask);
1024
1025
1026
1027
1028
        }
    }
    return $status;
}

1029

Penny Leach's avatar
Penny Leach committed
1030
1031
1032
/**
 * Function to require a plugin file. This is to avoid doing 
 * require and include directly with variables.
1033
 *
Penny Leach's avatar
Penny Leach committed
1034
1035
 * This function is the one safe point to require plugin files.
 * so USE it :)
1036
 *
1037
1038
1039
1040
1041
1042
1043
1044
 * blocktypes are special cases.  eg:
 *   system blocks: safe_require('blocktype', 'wall');
 *   artefact blocks: safe_require('blocktype', 'file/html');
 *
 * import/export plugins are special cases.  eg:
 *   main library: safe_require('export', 'leap');
 *   artefact plugin implementation: safe_require('export', 'leap/file');
 *
Penny Leach's avatar
Penny Leach committed
1045
1046
1047
1048
1049
1050
 * @param string $plugintype the type of plugin (eg artefact)
 * @param string $pluginname the name of the plugin (eg blog)
 * @param string $filename the name of the file to include within the plugin structure
 * @param string $function (optional, defaults to require) the require/include function to use
 * @param string $nonfatal (optional, defaults to false) just returns false if the file doesn't exist
 */
1051
function safe_require($plugintype, $pluginname, $filename='lib.php', $function='require_once', $nonfatal=false) {
1052
1053
    $plugintypes = plugin_types();
    if (!in_array($plugintype, $plugintypes)) {
1054
        throw new SystemException("\"$plugintype\" is not a valid plugin type");
1055
    }
1056
1057
    require_once(get_config('docroot') . $plugintype . '/lib.php');

1058
    if (!in_array($function,array('require', 'include', 'require_once', 'include_once'))) {
Penny Leach's avatar
Penny Leach committed
1059
1060
1061
        if (!empty($nonfatal)) {
            return false;
        }
1062
        throw new SystemException ('Invalid require type');
Penny Leach's avatar
Penny Leach committed
1063
1064
    }

1065
1066
1067
1068
1069
    if ($plugintype == 'blocktype') { // these are a bit of a special case
        $bits = explode('/', $pluginname);
        if (count($bits) == 2) {
           $fullpath = get_config('docroot') . 'artefact/' . $bits[0] . '/blocktype/' . $bits[1] . '/' . $filename;
        }
1070
        else {
1071
            try {
1072
                if ($artefactplugin = blocktype_artefactplugin($pluginname)) {
1073
1074
1075
1076
1077
1078
1079
                    $fullpath = get_config('docroot') . 'artefact/' . $artefactplugin . '/blocktype/' . $pluginname . '/'. $filename;
                }
            }
            catch (SQLException $e) {
                if (get_config('installed')) {
                    throw $e;
                }
1080
1081
            }
        }
1082
1083
1084
1085
1086
1087
1088
1089
    }
    // these can have parts living inside artefact directories as well.
    else if ($plugintype == 'export' || $plugintype == 'import') {
        $bits = explode('/', $pluginname);
        if (count($bits) == 2) {
            $fullpath = get_config('docroot') . 'artefact/' . $bits[1] . '/' . $plugintype . '/' . $bits[0] . '/' . $filename;
        }
    }
1090
1091
1092
1093
    if (empty($fullpath)) {
        $fullpath = get_config('docroot') . $plugintype . '/' . $pluginname . '/' . $filename;
    }

1094
    if (!file_exists($fullpath)) {
Penny Leach's avatar
Penny Leach committed
1095
1096
1097
        if (!empty($nonfatal)) {
            return false;
        }
1098
        throw new SystemException ("File $fullpath did not exist");
Penny Leach's avatar
Penny Leach committed
1099
1100
    }

1101
1102
    $realpath = realpath($fullpath);

Penny Leach's avatar
Penny Leach committed
1103
1104
1105
1106
    if (strpos($realpath, get_config('docroot') !== 0)) {
        if (!empty($nonfatal)) {
            return false;
        }
1107
        throw new SystemException ("File $fullpath was outside document root!");
Penny Leach's avatar
Penny Leach committed
1108
1109
1110
1111
1112
1113
1114
1115
1116
    }

    if ($function == 'require') { return require($realpath); }
    if ($function == 'include') { return include($realpath); }
    if ($function == 'require_once') { return require_once($realpath); }
    if ($function == 'include_once') { return include_once($realpath); }
    
}

1117
/**
1118
1119
1120
1121
 * This function returns the list of plugintypes we currently care about.
 *
 * NOTE: use plugin_types_installed if you just want the installed ones.
 *
1122
1123
1124
1125
1126
 * @return array of names
 */
function plugin_types() {
    static $pluginstocheck;
    if (empty($pluginstocheck)) {
1127
        // ORDER MATTERS! artefact has to be first!
1128
        $pluginstocheck = array('artefact', 'auth', 'notification', 'search', 'blocktype', 'interaction', 'grouptype', 'import', 'export');
1129
1130
1131
1132
    }
    return $pluginstocheck;
}

1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
/**
 * Returns plugin types that are actually installed
 */
function plugin_types_installed() {
    static $plugins = array();
    if (empty($plugins)) {
        require_once('ddl.php');
        foreach (plugin_types() as $plugin) {
            if (table_exists(new XMLDBTable("{$plugin}_installed"))) {
                $plugins[] = $plugin;
            }
        }
    }
    return $plugins;
}

1149
1150
1151
1152
1153
1154
/** 
 * This return returns the names of plugins installed 
 * for the given plugin type.
 * 
 * @param string $plugintype type of plugin
 */
1155
function plugins_installed($plugintype, $all=false) {
1156
1157
1158
1159
1160
    static $records = array();

    if (defined('INSTALLER') || !isset($records[$plugintype][true])) {

        $sort = $plugintype == 'blocktype' ? 'artefactplugin,name' : 'name';
1161
1162
1163
1164
1165
1166
1167
1168

        if ($rs = get_records_assoc($plugintype . '_installed', '', '', $sort)) {
            $records[$plugintype][true] = $rs;
        }
        else {
            $records[$plugintype][true] = array();
        }
        $records[$plugintype][false] = array();
1169
1170
1171
1172
1173
1174

        foreach ($records[$plugintype][true] as $r) {
            if ($r->active) {
                $records[$plugintype][false][$r->name] = $r;
            }
        }
1175
    }
1176
1177

    return $records[$plugintype][$all];
1178
1179
}

1180
1181
1182
1183
1184
1185
1186
1187
/**
 * Helper to call a static method when you do not know the name of the class
 * you want to call the method on. PHP5 does not support $class::method().
 */
function call_static_method($class, $method) {
    $args = func_get_args();
    array_shift($args);
    array_shift($args);
1188
    return call_user_func_array(array($class, $method), $args);
1189
1190
}

1191
1192
function generate_class_name() {
    $args = func_get_args();
1193
    if (count($args) == 2 && $args[0] == 'blocktype') {
1194
        return 'PluginBlocktype' . ucfirst(blocktype_namespaced_to_single($args[1]));
1195
    }
1196
1197
1198
    return 'Plugin' . implode('', array_map('ucfirst', $args));
}

1199
1200
1201
1202
function generate_artefact_class_name($type) {
    return 'ArtefactType' . ucfirst($type);
}

1203
1204
1205
1206
function generate_interaction_instance_class_name($type) {
    return 'Interaction' . ucfirst($type) . 'Instance';
}

1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
function blocktype_namespaced_to_single($blocktype) {
    if (strpos($blocktype, '/') === false) { // system blocktype
        return $blocktype;
    }
    return substr($blocktype, strpos($blocktype, '/') + 1 );
}

function blocktype_single_to_namespaced($blocktype, $artefact='') {
    if (empty($artefact)) {
        return $blocktype;
    }
    return $artefact . '/' . $blocktype;
1219
1220
}

1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
/**
 * Given a blocktype name, convert it to the namespaced version.
 *
 * This will be $artefacttype/$blocktype, or just plain $blocktype for system 
 * blocktypes.
 *
 * This is useful for language strings
 */
function blocktype_name_to_namespaced($blocktype) {
    static $resultcache = array();

    if (!isset($resultcache[$blocktype])) {
        $artefactplugin = get_field('blocktype_installed', 'artefactplugin', 'name', $blocktype);
        if ($artefactplugin) {
            $resultcache[$blocktype] = "$artefactplugin/$blocktype";
        }
        else {
            $resultcache[$blocktype] = $blocktype;
        }
    }

    return $resultcache[$blocktype];
}

1245
1246
1247
1248
1249
1250
1251
1252
1253
/* Get the name of the artefact plugin that provides a given blocktype */
function blocktype_artefactplugin($blocktype) {
    $installed = plugins_installed('blocktype');
    if (isset($installed[$blocktype])) {
        return $installed[$blocktype]->artefactplugin;
    }
    return false;
}

1254

1255
1256
1257
1258
1259
/**
 * Fires an event which can be handled by different parts of the system
 */
function handle_event($event, $data) {
    if (!$e = get_record('event_type', 'name', $event)) {
1260
        throw new SystemException("Invalid event");
Penny Leach's avatar
Penny Leach committed
1261
    }
1262

1263
    if ($data instanceof ArtefactType || $data instanceof BlockInstance) {
1264
1265
1266
        // leave it alone
    }
    else if (is_object($data)) {
1267
1268
        $data = (array)$data;
    }
1269
    else if (is_numeric($data)) {