MDL-25314 improved prevention of output buffering + detection of misc…

…onfigured servers Scripts that do not want buffered output just define NO_OUTPUT_BUFFERING before including config.php. The fileserving code now checks if the headers are already sent which detects misconfigured servers.
anovikov · Nov 19, 2010 · cbad562 · cbad562
1 parent 6e4453f
commit cbad562
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Showing 18 changed files with 279 additions and 255 deletions.
diff --git a/admin/bloglevelupgrade.php b/admin/bloglevelupgrade.php
@@ -1,6 +1,8 @@
 <?php
       /// Create "blog" forums in each course and copy blog entries from these courses' participants in these forums
 
+define('NO_OUTPUT_BUFFERING', true);
+
 require_once('../config.php');
 require_once($CFG->dirroot.'/course/lib.php');
 require_once($CFG->dirroot.'/blog/lib.php');
@@ -28,9 +30,7 @@
 
 /// Turn off time limits, sometimes upgrades can be slow.
 
-@set_time_limit(0);
-@ob_implicit_flush(true);
-while(@ob_end_flush());
+set_time_limit(0);
 
 $i = 0;
 

diff --git a/admin/cron.php b/admin/cron.php
@@ -40,24 +40,12 @@
 // CLI via web interface, please do not use this hack elsewhere
 define('CLI_SCRIPT', true);
 define('WEB_CRON_EMULATED_CLI', 'defined'); // ugly ugly hack, do not use elsewhere please
+define('NO_OUTPUT_BUFFERING', true);
 
 require('../config.php');
 require_once($CFG->libdir.'/clilib.php');
 require_once($CFG->libdir.'/cronlib.php');
 
-// disable compression, it would prevent closing of buffers
-if (ini_get('zlib.output_compression')) {
-    ini_set('zlib.output_compression', 'Off');
-}
-// no more headers and buffers
-ob_implicit_flush(true);
-while(ob_get_level()) {
-    if (!ob_end_clean()) {
-        // prevent infinite loop
-        break;
-    }
-}
-
 // extra safety
 session_get_instance()->write_close();
 

diff --git a/admin/index.php b/admin/index.php
@@ -38,19 +38,7 @@
     die;
 }
 
-// disable compression, it would prevent closing of buffers
-if (ini_get('zlib.output_compression')) {
-    ini_set('zlib.output_compression', 'Off');
-}
-
-// try to flush everything all the time
-ob_implicit_flush(true);
-while(ob_get_level()) {
-    if (!ob_end_clean()) {
-        // prevent infinite loop
-        break;
-    }
-}
+define('NO_OUTPUT_BUFFERING', true);
 
 require('../config.php');
 require_once($CFG->libdir.'/adminlib.php');    // various admin-only functions

diff --git a/admin/multilangupgrade.php b/admin/multilangupgrade.php
@@ -1,6 +1,8 @@
 <?php
       /// Search and replace strings throughout all texts in the whole database
 
+define('NO_OUTPUT_BUFFERING', true);
+
 require_once('../config.php');
 require_once($CFG->dirroot.'/course/lib.php');
 require_once($CFG->libdir.'/adminlib.php');
@@ -33,8 +35,6 @@
 /// Turn off time limits, sometimes upgrades can be slow.
 
 @set_time_limit(0);
-@ob_implicit_flush(true);
-while(@ob_end_flush());
 
 echo '<strong>Progress:</strong>';
 $i = 0;

diff --git a/admin/replace.php b/admin/replace.php
@@ -1,15 +1,12 @@
 <?php
       /// Search and replace strings throughout all texts in the whole database
 
+define('NO_OUTPUT_BUFFERING', true);
+
 require_once('../config.php');
 require_once($CFG->dirroot.'/course/lib.php');
 require_once($CFG->libdir.'/adminlib.php');
 
-// workaround for problems with compression
-if (ini_get('zlib.output_compression')) {
-    @ini_set('zlib.output_compression', 'Off');
-}
-
 admin_externalpage_setup('replace');
 
 $search  = optional_param('search', '', PARAM_RAW);

diff --git a/admin/report/security/index.php b/admin/report/security/index.php
@@ -23,6 +23,8 @@
 //                                                                       //
 ///////////////////////////////////////////////////////////////////////////
 
+define('NO_OUTPUT_BUFFERING', true);
+
 require_once('../../../config.php');
 require_once($CFG->dirroot.'/'.$CFG->admin.'/report/security/lib.php');
 require_once($CFG->libdir.'/adminlib.php');
@@ -49,8 +51,6 @@
 echo $OUTPUT->heading(get_string('pluginname', 'report_security'));
 
 echo '<div id="timewarning">'.get_string('timewarning', 'report_security').'</div>';
-while(@ob_end_flush());
-@flush();
 
 $strok       = '<span class="statusok">'.get_string('statusok', 'report_security').'</span>';
 $strinfo     = '<span class="statusinfo">'.get_string('statusinfo', 'report_security').'</span>';

diff --git a/admin/report/unittest/dbtest.php b/admin/report/unittest/dbtest.php
@@ -4,27 +4,14 @@
  * @package SimpleTestEx
  */
 
-/** */
+define('NO_OUTPUT_BUFFERING', true);
+
 require_once(dirname(__FILE__).'/../../../config.php');
 require_once($CFG->libdir.'/adminlib.php');
 require_once($CFG->libdir.'/simpletestcoveragelib.php');
 require_once('ex_simple_test.php');
 require_once('ex_reporter.php');
 
-// disable compression, it would prevent closing of buffers
-if (ini_get('zlib.output_compression')) {
-    ini_set('zlib.output_compression', 'Off');
-}
-
-// try to flush everything all the time
-ob_implicit_flush(true);
-while(ob_get_level()) {
-    if (!ob_end_clean()) {
-        // prevent infinite loop
-        break;
-    }
-}
-
 $showpasses   = optional_param('showpasses', false, PARAM_BOOL);
 $codecoverage = optional_param('codecoverage', false, PARAM_BOOL);
 $selected     = optional_param('selected', array(), PARAM_INT);

diff --git a/admin/report/unittest/index.php b/admin/report/unittest/index.php
@@ -8,27 +8,14 @@
  * @package SimpleTestEx
  */
 
-/** */
+define('NO_OUTPUT_BUFFERING', true);
+
 require_once(dirname(__FILE__).'/../../../config.php');
 require_once($CFG->libdir.'/adminlib.php');
 require_once($CFG->libdir.'/simpletestcoveragelib.php');
 require_once('ex_simple_test.php');
 require_once('ex_reporter.php');
 
-// disable compression, it would prevent closing of buffers
-if (ini_get('zlib.output_compression')) {
-    ini_set('zlib.output_compression', 'Off');
-}
-
-// try to flush everything all the time
-ob_implicit_flush(true);
-while(ob_get_level()) {
-    if (!ob_end_clean()) {
-        // prevent infinite loop
-        break;
-    }
-}
-
 // Always run the unit tests in developer debug mode.
 $CFG->debug = DEBUG_DEVELOPER;
 error_reporting($CFG->debug);

diff --git a/calendar/export_execute.php b/calendar/export_execute.php
@@ -152,7 +152,7 @@
 }
 
 //IE compatibility HACK!
-if(ini_get('zlib.output_compression')) {
+if (ini_get_bool('zlib.output_compression')) {
     ini_set('zlib.output_compression', 'Off');
 }
 

diff --git a/lang/en/error.php b/lang/en/error.php
@@ -129,6 +129,7 @@
 $string['cannotsavefile'] = 'Cannot save the file "{$a}"!';
 $string['cannotsavemd5file'] = 'Cannot save md5 file';
 $string['cannotsavezipfile'] = 'Cannot save ZIP file';
+$string['cannotservefile'] = 'Can not serve file - server configuration problem.';
 $string['cannotsetparentforcatoritem'] = 'Cannot set parent for category or course item!';
 $string['cannotsetpassword'] = 'Could not set user password!';
 $string['cannotsetprefgrade'] = 'Could not set preference aggregationview to {$a} for this grade category';

diff --git a/lib/adminlib.php b/lib/adminlib.php
@@ -5919,8 +5919,6 @@ function db_replace($search, $replace) {
 
     /// Turn off time limits, sometimes upgrades can be slow.
     @set_time_limit(0);
-    @ob_implicit_flush(true);
-    while(@ob_end_flush());
 
     if (!$tables = $DB->get_tables() ) {    // No tables yet at all.
         return false;