gl-website-deployer/admin/phpMyAdmin/libraries/classes/OutputBuffering.php
2024-11-19 08:02:04 +01:00

175 lines
4.1 KiB
PHP

<?php
/**
* Output buffering wrapper
*/
declare(strict_types=1);
namespace PhpMyAdmin;
use function defined;
use function flush;
use function function_exists;
use function header;
use function ini_get;
use function ob_end_clean;
use function ob_flush;
use function ob_get_contents;
use function ob_get_length;
use function ob_get_level;
use function ob_get_status;
use function ob_start;
use function register_shutdown_function;
use function sprintf;
/**
* Output buffering wrapper class
*/
class OutputBuffering
{
/** @var self */
private static $instance;
/** @var int */
private $mode;
/** @var string */
private $content;
/** @var bool */
private $on;
/**
* Initializes class
*/
private function __construct()
{
$this->mode = $this->getMode();
$this->on = false;
}
/**
* This function could be used eventually to support more modes.
*
* @return int the output buffer mode
*/
private function getMode()
{
$mode = 0;
if ($GLOBALS['cfg']['OBGzip'] && function_exists('ob_start')) {
if (ini_get('output_handler') === 'ob_gzhandler') {
// If a user sets the output_handler in php.ini to ob_gzhandler, then
// any right frame file in phpMyAdmin will not be handled properly by
// the browser. My fix was to check the ini file within the
// PMA_outBufferModeGet() function.
$mode = 0;
} elseif (function_exists('ob_get_level') && ob_get_level() > 0) {
// happens when php.ini's output_buffering is not Off
ob_end_clean();
$mode = 1;
} else {
$mode = 1;
}
}
// Zero (0) is no mode or in other words output buffering is OFF.
// Follow 2^0, 2^1, 2^2, 2^3 type values for the modes.
// Useful if we ever decide to combine modes. Then a bitmask field of
// the sum of all modes will be the natural choice.
return $mode;
}
/**
* Returns the singleton OutputBuffering object
*
* @return OutputBuffering object
*/
public static function getInstance()
{
if (empty(self::$instance)) {
self::$instance = new OutputBuffering();
}
return self::$instance;
}
/**
* This function will need to run at the top of all pages if output
* output buffering is turned on. It also needs to be passed $mode from
* the PMA_outBufferModeGet() function or it will be useless.
*/
public function start(): void
{
if ($this->on) {
return;
}
if ($this->mode && function_exists('ob_gzhandler')) {
ob_start('ob_gzhandler');
}
ob_start();
$this->sendHeader('X-ob_mode', (string) $this->mode);
register_shutdown_function(
[
self::class,
'stop',
]
);
$this->on = true;
}
private function sendHeader(string $name, string $value): void
{
if (defined('TESTSUITE')) {
return;
}
header(sprintf('%s: %s', $name, $value));
}
/**
* This function will need to run at the bottom of all pages if output
* buffering is turned on. It also needs to be passed $mode from the
* PMA_outBufferModeGet() function or it will be useless.
*/
public static function stop(): void
{
$buffer = self::getInstance();
if (! $buffer->on) {
return;
}
$buffer->on = false;
$buffer->content = ob_get_contents();
if (ob_get_length() <= 0) {
return;
}
ob_end_clean();
}
/**
* Gets buffer content
*
* @return string buffer content
*/
public function getContents()
{
return $this->content;
}
/**
* Flushes output buffer
*/
public function flush(): void
{
if (ob_get_status() && $this->mode) {
ob_flush();
} else {
flush();
}
}
}