/**
* Copyright (C) 2014-2025 ServMask Inc.
*
* 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.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*
* Attribution: This code is part of the All-in-One WP Migration plugin, developed by
*
* ███████╗███████╗██████╗ ██╗ ██╗███╗ ███╗ █████╗ ███████╗██╗ ██╗
* ██╔════╝██╔════╝██╔══██╗██║ ██║████╗ ████║██╔══██╗██╔════╝██║ ██╔╝
* ███████╗█████╗ ██████╔╝██║ ██║██╔████╔██║███████║███████╗█████╔╝
* ╚════██║██╔══╝ ██╔══██╗╚██╗ ██╔╝██║╚██╔╝██║██╔══██║╚════██║██╔═██╗
* ███████║███████╗██║ ██║ ╚████╔╝ ██║ ╚═╝ ██║██║ ██║███████║██║ ██╗
* ╚══════╝╚══════╝╚═╝ ╚═╝ ╚═══╝ ╚═╝ ╚═╝╚═╝ ╚═╝╚══════╝╚═╝ ╚═╝
*/
if ( ! defined( 'ABSPATH' ) ) {
die( 'Kangaroos cannot jump here' );
}
class Ai1wm_Compressor extends Ai1wm_Archiver {
/**
* Overloaded constructor that opens the passed file for writing
*
* @param string $file_name File to use as archive
* @param string $file_password File password string
* @param string $file_compression File compression type
*/
public function __construct( $file_name, $file_password = null, $file_compression = null ) {
// Call parent, to initialize variables
parent::__construct( $file_name, $file_password, $file_compression, true );
}
/**
* Add a file to the archive
*
* @param string $file_name File to add to the archive
* @param string $new_file_name Write the file with a different name
* @param int $file_bytes_read Amount of the bytes we read
* @param int $file_bytes_offset File bytes offset
* @param int $file_bytes_written Amount of the bytes we wrote
* @param string|null $file_crc File CRC32 checksum (passed by reference, optional)
*
* @throws \Ai1wm_Not_Seekable_Exception
* @throws \Ai1wm_Not_Writable_Exception
* @throws \Ai1wm_Quota_Exceeded_Exception
*
* @return bool
*/
public function add_file( $file_name, $new_file_name = '', &$file_bytes_read = 0, &$file_bytes_offset = 0, &$file_bytes_written = 0, &$file_crc = null ) {
// Replace forward slash with current directory separator in file name
$file_name = ai1wm_replace_forward_slash_with_directory_separator( $file_name );
// Escape Windows directory separator in file name
$file_name = ai1wm_escape_windows_directory_separator( $file_name );
// Flag to hold if file data has been processed
$completed = true;
// Start time
$start = microtime( true );
// Open the file for reading in binary mode (fopen may return null for quarantined files)
if ( ( $file_handle = @fopen( $file_name, 'rb' ) ) ) {
// Start native hash for current chunk
$hash_ctx = Ai1wm_Crc::init_crc32();
// Get header block with empty CRC placeholder
if ( ( $block = $this->get_file_block( $file_name, $new_file_name, '' ) ) ) {
// Write header block
if ( $file_bytes_offset === 0 ) {
if ( ( $file_bytes = @fwrite( $this->file_handle, $block ) ) !== false ) {
if ( strlen( $block ) !== $file_bytes ) {
throw new Ai1wm_Quota_Exceeded_Exception( sprintf( __( 'Out of disk space. Could not write header to file. File: %s', 'all-in-one-wp-migration' ), $this->file_name ) );
}
} else {
throw new Ai1wm_Not_Writable_Exception( sprintf( __( 'Could not write header to file. File: %s', 'all-in-one-wp-migration' ), $this->file_name ) );
}
}
// Set file offset
if ( @fseek( $file_handle, $file_bytes_offset, SEEK_SET ) !== -1 ) {
$file_bytes_read = 0;
// Cache config file check outside the loop
$should_process_file = ! in_array( $new_file_name, ai1wm_config_filters() );
// Read the file in 512KB chunks
while ( false === @feof( $file_handle ) ) {
if ( ( $file_content = @fread( $file_handle, static::READ_CHUNK_SIZE ) ) !== false ) {
// Empty read indicates EOF
if ( strlen( $file_content ) === 0 ) {
break;
}
// Add the amount of bytes we read
$file_bytes_read += strlen( $file_content );
// Update CRC with original content (BEFORE compression/encryption)
Ai1wm_Crc::update_crc32( $hash_ctx, $file_content );
// Do not encrypt or compress config files
if ( $should_process_file === true ) {
// Add chunk data compression
if ( ! empty( $this->file_compression ) ) {
switch ( $this->file_compression ) {
case 'gzip':
$file_content = gzcompress( $file_content, 9 );
break;
case 'bzip2':
$file_content = bzcompress( $file_content, 9 );
break;
}
}
// Add chunk data encryption
if ( ! empty( $this->file_password ) ) {
$file_content = ai1wm_encrypt_string( $file_content, $this->file_password );
}
// Add variable length chunk size before chunk data
if ( ! empty( $this->file_compression ) ) {
$file_content = pack( 'N', strlen( $file_content ) ) . $file_content;
}
}
if ( ( $file_bytes = @fwrite( $this->file_handle, $file_content ) ) !== false ) {
if ( strlen( $file_content ) !== $file_bytes ) {
throw new Ai1wm_Quota_Exceeded_Exception( sprintf( __( 'Out of disk space. Could not write content to file. File: %s', 'all-in-one-wp-migration' ), $this->file_name ) );
}
} else {
throw new Ai1wm_Not_Writable_Exception( sprintf( __( 'Could not write content to file. File: %s', 'all-in-one-wp-migration' ), $this->file_name ) );
}
// Add the amount of bytes we wrote
$file_bytes_written += $file_bytes;
}
// Time elapsed
if ( ( $timeout = apply_filters( 'ai1wm_completed_timeout', 10 ) ) ) {
if ( ( microtime( true ) - $start ) > $timeout ) {
$completed = false;
break;
}
}
}
// Add the amount of bytes we read
$file_bytes_offset += $file_bytes_read;
}
// Combine and finalize CRC
if ( empty( $file_crc ) ) {
$file_crc = Ai1wm_Crc::finalize_crc32( $hash_ctx );
} else {
$file_crc = Ai1wm_Crc::combine_crc32( $file_crc, Ai1wm_Crc::finalize_crc32( $hash_ctx ), $file_bytes_read );
}
// Write file size to file header
if ( ( $file_size_block = $this->get_file_size_block( $file_bytes_written ) ) ) {
// Seek to beginning of file size (back over: content + crc32(8) + path(4088) + mtime(12) + size(14))
if ( @fseek( $this->file_handle, - $file_bytes_written - 8 - 4088 - 12 - 14, SEEK_CUR ) === -1 ) {
throw new Ai1wm_Not_Seekable_Exception( __( 'Your PHP is 32-bit. In order to export your file, please change your PHP version to 64-bit and try again. Technical details', 'all-in-one-wp-migration' ) );
}
// Write file size to file header
if ( ( $file_bytes = @fwrite( $this->file_handle, $file_size_block ) ) !== false ) {
if ( strlen( $file_size_block ) !== $file_bytes ) {
throw new Ai1wm_Quota_Exceeded_Exception( sprintf( __( 'Out of disk space. Could not write size to file. File: %s', 'all-in-one-wp-migration' ), $this->file_name ) );
}
} else {
throw new Ai1wm_Not_Writable_Exception( sprintf( __( 'Could not write size to file. File: %s', 'all-in-one-wp-migration' ), $this->file_name ) );
}
// Seek to beginning of file CRC (forward over: mtime(12) + path(4088))
if ( @fseek( $this->file_handle, + 12 + 4088, SEEK_CUR ) === -1 ) {
throw new Ai1wm_Not_Seekable_Exception( __( 'Your PHP is 32-bit. In order to export your file, please change your PHP version to 64-bit and try again. Technical details', 'all-in-one-wp-migration' ) );
}
// Write file CRC to file header
if ( ( $file_crc_block = $this->get_file_crc_block( $file_crc ) ) ) {
if ( ( $file_bytes = @fwrite( $this->file_handle, $file_crc_block ) ) !== false ) {
if ( strlen( $file_crc_block ) !== $file_bytes ) {
throw new Ai1wm_Quota_Exceeded_Exception( sprintf( __( 'Out of disk space. Could not write CRC to file. File: %s', 'all-in-one-wp-migration' ), $this->file_name ) );
}
}
}
// Seek to end of file content (forward over: content)
if ( @fseek( $this->file_handle, + $file_bytes_written, SEEK_CUR ) === -1 ) {
throw new Ai1wm_Not_Seekable_Exception( __( 'Your PHP is 32-bit. In order to export your file, please change your PHP version to 64-bit and try again. Technical details', 'all-in-one-wp-migration' ) );
}
}
}
// Close the handle
@fclose( $file_handle );
}
return $completed;
}
/**
* Generate binary block header for a file
*
* @param string $file_name Filename to generate block header for
* @param string $new_file_name Write the file with a different name
* @param string|null $crc32 CRC32 checksum (optional)
*
* @return string
*/
private function get_file_block( $file_name, $new_file_name = '', $crc32 = null ) {
$block = '';
// Get stats about the file
if ( ( $stat = @stat( $file_name ) ) !== false ) {
// Filename of the file we are accessing
if ( empty( $new_file_name ) ) {
$name = ai1wm_basename( $file_name );
} else {
$name = ai1wm_basename( $new_file_name );
}
// Size in bytes of the file
$size = $stat['size'];
// Last time the file was modified
$date = $stat['mtime'];
// Replace current directory separator with backward slash in file path
if ( empty( $new_file_name ) ) {
$path = ai1wm_replace_directory_separator_with_forward_slash( ai1wm_dirname( $file_name ) );
} else {
$path = ai1wm_replace_directory_separator_with_forward_slash( ai1wm_dirname( $new_file_name ) );
}
// Only calculate CRC if not provided
if ( empty( $crc32 ) ) {
$crc32 = Ai1wm_Crc::calculate_file_crc32( $file_name );
}
// Concatenate block format parts
$format = implode( '', $this->block_format );
// Pack file data into binary string
$block = pack( $format, $name, $size, $date, $path, $crc32 );
}
return $block;
}
/**
* Generate file size binary block header for a file
*
* @param int $file_size File size
*
* @return string
*/
public function get_file_size_block( $file_size ) {
$block = '';
// Pack file data into binary string
if ( isset( $this->block_format[1] ) ) {
$block = pack( $this->block_format[1], $file_size );
}
return $block;
}
/**
* Generate file CRC binary block header for a file
*
* @param int $file_crc File CRC
*
* @return string
*/
public function get_file_crc_block( $file_crc ) {
$block = '';
// Pack file data into binary string
if ( isset( $this->block_format[4] ) ) {
$block = pack( $this->block_format[4], $file_crc );
}
return $block;
}
}