path: root/srcs/phpmyadmin/libraries/classes/Export.php

<?php
/* vim: set expandtab sw=4 ts=4 sts=4: */
/**
 * function for the main export logic
 *
 * @package PhpMyAdmin
 */
declare(strict_types=1);

namespace PhpMyAdmin;

use PhpMyAdmin\Plugins\ExportPlugin;
use PhpMyAdmin\Plugins\SchemaPlugin;

/**
 * PhpMyAdmin\Export class
 *
 * @package PhpMyAdmin
 */
class Export
{
    /**
     * @var DatabaseInterface
     */
    private $dbi;

    /**
     * Export constructor.
     * @param DatabaseInterface $dbi DatabaseInterface instance
     */
    public function __construct($dbi)
    {
        $this->dbi = $dbi;
    }

    /**
     * Sets a session variable upon a possible fatal error during export
     *
     * @return void
     */
    public function shutdown(): void
    {
        $error = error_get_last();
        if ($error != null && mb_strpos($error['message'], "execution time")) {
            //set session variable to check if there was error while exporting
            $_SESSION['pma_export_error'] = $error['message'];
        }
    }

    /**
     * Detect ob_gzhandler
     *
     * @return bool
     */
    public function isGzHandlerEnabled(): bool
    {
        return in_array('ob_gzhandler', ob_list_handlers());
    }

    /**
     * Detect whether gzencode is needed; it might not be needed if
     * the server is already compressing by itself
     *
     * @return bool Whether gzencode is needed
     */
    public function gzencodeNeeded(): bool
    {
        /*
         * We should gzencode only if the function exists
         * but we don't want to compress twice, therefore
         * gzencode only if transparent compression is not enabled
         * and gz compression was not asked via $cfg['OBGzip']
         * but transparent compression does not apply when saving to server
         */
        $chromeAndGreaterThan43 = PMA_USR_BROWSER_AGENT == 'CHROME'
            && PMA_USR_BROWSER_VER >= 43; // see bug #4942

        return function_exists('gzencode')
            && ((! ini_get('zlib.output_compression')
                    && ! $this->isGzHandlerEnabled())
                || $GLOBALS['save_on_server']
                || $chromeAndGreaterThan43);
    }

    /**
     * Output handler for all exports, if needed buffering, it stores data into
     * $dump_buffer, otherwise it prints them out.
     *
     * @param string $line the insert statement
     *
     * @return bool Whether output succeeded
     */
    public function outputHandler(?string $line): bool
    {
        global $time_start, $dump_buffer, $dump_buffer_len, $save_filename;

        // Kanji encoding convert feature
        if ($GLOBALS['output_kanji_conversion']) {
            $line = Encoding::kanjiStrConv(
                $line,
                $GLOBALS['knjenc'],
                isset($GLOBALS['xkana']) ? $GLOBALS['xkana'] : ''
            );
        }

        // If we have to buffer data, we will perform everything at once at the end
        if ($GLOBALS['buffer_needed']) {
            $dump_buffer .= $line;
            if ($GLOBALS['onfly_compression']) {
                $dump_buffer_len += strlen($line);

                if ($dump_buffer_len > $GLOBALS['memory_limit']) {
                    if ($GLOBALS['output_charset_conversion']) {
                        $dump_buffer = Encoding::convertString(
                            'utf-8',
                            $GLOBALS['charset'],
                            $dump_buffer
                        );
                    }
                    if ($GLOBALS['compression'] == 'gzip'
                        && $this->gzencodeNeeded()
                    ) {
                        // as a gzipped file
                        // without the optional parameter level because it bugs
                        $dump_buffer = gzencode($dump_buffer);
                    }
                    if ($GLOBALS['save_on_server']) {
                        $write_result = @fwrite($GLOBALS['file_handle'], $dump_buffer);
                        // Here, use strlen rather than mb_strlen to get the length
                        // in bytes to compare against the number of bytes written.
                        if ($write_result != strlen($dump_buffer)) {
                            $GLOBALS['message'] = Message::error(
                                __('Insufficient space to save the file %s.')
                            );
                            $GLOBALS['message']->addParam($save_filename);
                            return false;
                        }
                    } else {
                        echo $dump_buffer;
                    }
                    $dump_buffer = '';
                    $dump_buffer_len = 0;
                }
            } else {
                $time_now = time();
                if ($time_start >= $time_now + 30) {
                    $time_start = $time_now;
                    header('X-pmaPing: Pong');
                } // end if
            }
        } elseif ($GLOBALS['asfile']) {
            if ($GLOBALS['output_charset_conversion']) {
                $line = Encoding::convertString(
                    'utf-8'