theme/styles.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   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.
  13 //
  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/>.
  16
  17 /**
  18  * This file is responsible for serving the one huge CSS of each theme.
  19  *
  20  * @package   core
  21  * @copyright 2009 Petr Skoda (skodak)  {@link http://skodak.org}
  22  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24
  25 // Disable moodle specific debug messages and any errors in output,
  26 // comment out when debugging or better look into error log!
  27 define('NO_DEBUG_DISPLAY', true);
  28
  29 define('ABORT_AFTER_CONFIG', true);
  30 require('../config.php');
  31 require_once($CFG->dirroot.'/lib/csslib.php');
  32
  33 if ($slashargument = min_get_slash_argument()) {
  34     $slashargument = ltrim($slashargument, '/');
  35     if (substr_count($slashargument, '/') < 2) {
  36         css_send_css_not_found();
  37     }
  38
  39     if (strpos($slashargument, '_s/') === 0) {
  40         // Can't use SVG.
  41         $slashargument = substr($slashargument, 3);
  42         $usesvg = false;
  43     } else {
  44         $usesvg = true;
  45     }
  46
  47     $chunk = null;
  48     if (preg_match('#/(chunk(\d+)(/|$))#', $slashargument, $matches)) {
  49         $chunk = (int)$matches[2];
  50         $slashargument = str_replace($matches[1], '', $slashargument);
  51     }
  52
  53     list($themename, $rev, $type) = explode('/', $slashargument, 3);
  54     $themename = min_clean_param($themename, 'SAFEDIR');
  55     $rev       = min_clean_param($rev, 'INT');
  56     $type      = min_clean_param($type, 'SAFEDIR');
  57
  58 } else {
  59     $themename = min_optional_param('theme', 'standard', 'SAFEDIR');
  60     $rev       = min_optional_param('rev', 0, 'INT');
  61     $type      = min_optional_param('type', 'all', 'SAFEDIR');
  62     $chunk     = min_optional_param('chunk', null, 'INT');
  63     $usesvg    = (bool)min_optional_param('svg', '1', 'INT');
  64 }
  65
  66 if ($type === 'editor') {
  67     // The editor CSS is never chunked.
  68     $chunk = null;
  69 } else if ($type === 'all') {
  70     // We're fine.
  71 } else {
  72     css_send_css_not_found();
  73 }
  74
  75 if (file_exists("$CFG->dirroot/theme/$themename/config.php")) {
  76     // The theme exists in standard location - ok.
  77 } else if (!empty($CFG->themedir) and file_exists("$CFG->themedir/$themename/config.php")) {
  78     // Alternative theme location contains this theme - ok.
  79 } else {
  80     header('HTTP/1.0 404 not found');
  81     die('Theme was not found, sorry.');
  82 }
  83
  84 $candidatedir = "$CFG->localcachedir/theme/$rev/$themename/css";
  85 $etag = "$rev/$themename/$type";
  86 $candidatename = $type;
  87 if (!$usesvg) {
  88     // Add to the sheet name, one day we'll be able to just drop this.
  89     $candidatedir .= '/nosvg';
  90     $etag .= '/nosvg';
  91 }
  92
  93 if ($chunk !== null) {
  94     $etag .= '/chunk'.$chunk;
  95     $candidatename .= '.'.$chunk;
  96 }
  97 $candidatesheet = "$candidatedir/$candidatename.css";
  98 $etag = sha1($etag);
  99
 100 if (file_exists($candidatesheet)) {
 101     if (!empty($_SERVER['HTTP_IF_NONE_MATCH']) || !empty($_SERVER['HTTP_IF_MODIFIED_SINCE'])) {
 102         // We do not actually need to verify the etag value because our files
 103         // never change in cache because we increment the rev counter.
 104         css_send_unmodified(filemtime($candidatesheet), $etag);
 105     }
 106     css_send_cached_css($candidatesheet, $etag);
 107 }
 108
 109 // Ok, now we need to start normal moodle script, we need to load all libs and $DB.
 110 define('ABORT_AFTER_CONFIG_CANCEL', true);
 111
 112 define('NO_MOODLE_COOKIES', true); // Session not used here.
 113 define('NO_UPGRADE_CHECK', true);  // Ignore upgrade check.
 114
 115 require("$CFG->dirroot/lib/setup.php");
 116
 117 $theme = theme_config::load($themename);
 118 $theme->force_svg_use($usesvg);
 119
 120 $themerev = theme_get_revision();
 121
 122 $cache = true;
 123 if ($themerev <= 0 or $themerev != $rev) {
 124     $rev = $themerev;
 125     $cache = false;
 126
 127     $candidatedir = "$CFG->localcachedir/theme/$rev/$themename/css";
 128     $etag = "$rev/$themename/$type";
 129     $candidatename = $type;
 130     if (!$usesvg) {
 131         // Add to the sheet name, one day we'll be able to just drop this.
 132         $candidatedir .= '/nosvg';
 133         $etag .= '/nosvg';
 134     }
 135
 136     if ($chunk !== null) {
 137         $etag .= '/chunk'.$chunk;
 138         $candidatename .= '.'.$chunk;
 139     }
 140     $candidatesheet = "$candidatedir/$candidatename.css";
 141     $etag = sha1($etag);
 142 }
 143
 144 make_localcache_directory('theme', false);
 145
 146 if ($type === 'editor') {
 147     $csscontent = $theme->get_css_content_editor();
 148     css_store_css($theme, "$candidatedir/editor.css", $csscontent, false);
 149
 150 } else {
 151
 152     $lock = null;
 153
 154     // Lock system to prevent concurrent requests to compile LESS, which is really slow and CPU intensive.
 155     // Each client should wait for one to finish the compilation before starting a new compiling process.
 156     // We only do this when the file will be cached...
 157     if ($type === 'less' && $cache) {
 158         $lockfactory = \core\lock\lock_config::get_lock_factory('core_theme_get_css_content');
 159         // We wait for the lock to be acquired, the timeout does not need to be strict here.
 160         $lock = $lockfactory->get_lock($themename, rand(15, 30));
 161         if (file_exists($candidatesheet)) {
 162             // The file was built while we waited for the lock, we release the lock and serve the file.
 163             if ($lock) {
 164                 $lock->release();
 165             }
 166             css_send_cached_css($candidatesheet, $etag);
 167         }
 168     }
 169
 170     // Older IEs require smaller chunks.
 171     $csscontent = $theme->get_css_content();
 172
 173     $relroot = preg_replace('|^http.?://[^/]+|', '', $CFG->wwwroot);
 174     if (!empty($slashargument)) {
 175         if ($usesvg) {
 176             $chunkurl = "{$relroot}/theme/styles.php/{$themename}/{$rev}/all";
 177         } else {
 178             $chunkurl = "{$relroot}/theme/styles.php/_s/{$themename}/{$rev}/all";
 179         }
 180     } else {
 181         if ($usesvg) {
 182             $chunkurl = "{$relroot}/theme/styles.php?theme={$themename}&rev={$rev}&type=all";
 183         } else {
 184             $chunkurl = "{$relroot}/theme/styles.php?theme={$themename}&rev={$rev}&type=all&svg=0";
 185         }
 186     }
 187
 188     css_store_css($theme, "$candidatedir/all.css", $csscontent, true, $chunkurl);
 189
 190     // Release the lock.
 191     if ($lock) {
 192         $lock->release();
 193     }
 194 }
 195
 196 if (!$cache) {
 197     // Do not pollute browser caches if invalid revision requested,
 198     // let's ignore legacy IE breakage here too.
 199     css_send_uncached_css($csscontent);
 200
 201 } else if ($chunk !== null and file_exists($candidatesheet)) {
 202     // Greetings stupid legacy IEs!
 203     css_send_cached_css($candidatesheet, $etag);
 204
 205 } else {
 206     // Real browsers - this is the expected result!
 207     css_send_cached_css_content($csscontent, $etag);
 208 }