<?php /** * Akeeba Engine * * @package akeebaengine * @copyright Copyright (c)2006-2022 Nicholas K. Dionysopoulos / Akeeba Ltd * @license GNU General Public License version 3, or later */ namespace Akeeba\Engine\Archiver; defined('AKEEBAENGINE') || die(); use Akeeba\Engine\Base\Exceptions\ErrorException; use Akeeba\Engine\Base\Exceptions\WarningException; use Akeeba\Engine\Factory; use Akeeba\Engine\Util\CRC32; use RuntimeException; class Zip extends BaseArchiver { /** @var string Beginning of central directory record. */ private $centralDirectoryRecordStartSignature = "\x50\x4b\x01\x02"; /** @var string End of central directory record. */ private $centralDirectoryRecordEndSignature = "\x50\x4b\x05\x06"; /** @var string Beginning of file contents. */ private $fileHeaderSignature = "\x50\x4b\x03\x04"; /** @var string The name of the temporary file holding the ZIP's Central Directory */ private $centralDirectoryFilename; /** @var integer The total number of files and directories stored in the ZIP archive */ private $totalFilesCount; /** @var integer The total size of data in the archive. Note: On 32-bit versions of PHP, this will overflow for archives over 2Gb! */ private $totalCompressedSize = 0; /** @var integer The chunk size for CRC32 calculations */ private $AkeebaPackerZIP_CHUNK_SIZE; /** @var int Current part file number */ private $currentPartNumber = 1; /** @var int Total number of part files */ private $totalParts = 1; /** * Class constructor - initializes internal operating parameters * * @return void */ public function __construct() { Factory::getLog()->debug(__CLASS__ . " :: New instance"); // Find the optimal chunk size for ZIP archive processing $this->findOptimalChunkSize(); Factory::getLog()->debug("Chunk size for CRC is now " . $this->AkeebaPackerZIP_CHUNK_SIZE . " bytes"); // Should I use Symlink Target Storage? $this->enableSymlinkTargetStorage(); parent::__construct(); if (!function_exists('hash_file') || !function_exists('hash')) { $action = version_compare(PHP_VERSION, '7.4.0', 'lt') ? 'Please ask your host to enable the PHP hash extension and to make sure the hash_file() and hash() functions are not disabled.' : 'Please ask your host to change their PHP configuration so that the hash_file() and hash() functions are not disabled.'; Factory::getLog()->warning( sprintf( 'Your server lacks support for the hash_file() and/or hash() functions. CRC32 checksum cannot be calculated. Third party ZIP extraction tools may report the backup archive as broken. %s', $action ) ); } } /** * Initialises the archiver class, creating the archive from an existent * installer's JPA archive. * * @param string $sourceJPAPath Absolute path to an installer's JPA archive * @param string $targetArchivePath Absolute path to the generated archive * @param array $options A named key array of options (optional). This is currently not supported * * @return void */ public function initialize($targetArchivePath, $options = []) { Factory::getLog()->debug(__CLASS__ . " :: initialize - archive $targetArchivePath"); // Get names of temporary files $this->_dataFileName = $targetArchivePath; // Should we enable split archive feature? $this->enableSplitArchives(); // Create the Central Directory temporary file $this->createCentralDirectoryTempFile(); // Try to kill the archive if it exists $this->createNewBackupArchive(); // On split archives, include the "Split ZIP" header, for PKZIP 2.50+ compatibility if ($this->useSplitArchive) { $this->openArchiveForOutput(); $this->fwrite($this->fp, "\x50\x4b\x07\x08"); } } public function finalize() { $this->finalizeZIPFile(); } /** * Glues the Central Directory of the ZIP file to the archive and takes care about the differences between single * and multipart archives. * * Official ZIP file format: http://www.pkware.com/appnote.txt * * @return void */ public function finalizeZIPFile() { // 1. Get size of central directory clearstatcache(); $cdOffset = @filesize($this->_dataFileName); $this->totalCompressedSize += $cdOffset; $cdSize = @filesize($this->centralDirectoryFilename); // 2. Append Central Directory to data file and remove the CD temp file afterwards if (!is_null($this->fp)) { $this->fclose($this->fp); } if (!is_null($this->cdfp)) { $this->fclose($this->cdfp); } $this->openArchiveForOutput(true); /** * Do not remove the fcloseByName line! This is required for post-processing multipart archives when for any * reason $this->filePointers[$this->centralDirectoryFilename] contains null instead of boolean false. In this * case the while loop would be stuck forever and the backup would fail. This HAS happened and I have been able * to reproduce it but I did not have enough time to identify the real root cause. This workaround, however, * works. */ $this->fcloseByName($this->centralDirectoryFilename); $this->cdfp = $this->fopen($this->centralDirectoryFilename, "r"); if ($this->cdfp === false) { // Already glued, return $this->fclose($this->fp); $this->fp = null; $this->cdfp = null; return; } // Comment length (I need it before I start gluing the archive) $comment_length = akstrlen($this->_comment); // Special consideration for split ZIP files if ($this->useSplitArchive) { // Calculate size of Central Directory + EOCD records $total_cd_eocd_size = $cdSize + 22 + $comment_length; // Free space on the part $free_space = $this->getPartFreeSize(); if (($free_space < $total_cd_eocd_size) && ($total_cd_eocd_size > 65536)) { // Not enough space on archive for CD + EOCD, will go on separate part $this->createAndOpenNewPart(true); } } /** * Write the CD record * * Note about is_resource: in some circumstances where multipart ZIP files are generated, the $this->cdfp will * contain a null value. This seems to happen when $this->fopen returns null, i.e. $this->filePointers has a * null value instead of a file pointer (resource). Why this happens is unclear but the workaround is to remove * the null value from $this->filePointers and retry $this->fopen. Normally this should not be required since we * already to the fcloseByName/fopen dance above. This if-block is our last hope to catch a potential issue * which would either make the while loop go infinite (not anymore, I've patched it) or the Central Directory * not get written to the archive, which results in a broken archive. */ if (!is_resource($this->cdfp)) { $this->fcloseByName($this->centralDirectoryFilename); $this->cdfp = $this->fopen($this->centralDirectoryFilename, "r"); // We tried reopening the central directory file and failed again. Time to report a fatal error. if (!$this->cdfp) { throw new RuntimeException("Cannot open central directory temporary file {$this->centralDirectoryFilename} for reading."); } } while (!feof($this->cdfp) && is_resource($this->cdfp)) { /** * Why not split the Central Directory between parts? * * APPNOTE.TXT §8.5.2 "The central directory may span segment boundaries, but no single record in the * central directory should be split across segments." * * This would require parsing the CD temp file to prevent any CD record from spanning across two parts. * But how many bytes is each CD record? It's about 100 bytes per file which gives us about 10,400 files * per MB. Even a 2MB part size holds more than 20,000 file records. A typical 10Mb part size holds more * files than the largest backup I've ever seen. Therefore there is no need to waste computational power * to see if we need to span the Central Directory between parts. */ $chunk = fread($this->cdfp, _AKEEBA_DIRECTORY_READ_CHUNK); $this->fwrite($this->fp, $chunk); } unset($chunk); // Delete the temporary CD file $this->fclose($this->cdfp); $this->cdfp = null; Factory::getTempFiles()->unregisterAndDeleteTempFile($this->centralDirectoryFilename); // 3. Write the rest of headers to the end of the ZIP file $this->fwrite($this->fp, $this->centralDirectoryRecordEndSignature); if ($this->useSplitArchive) { // Split ZIP files, enter relevant disk number information $this->fwrite($this->fp, pack('v', $this->totalParts - 1)); /* Number of this disk. */ $this->fwrite($this->fp, pack('v', $this->totalParts - 1)); /* Disk with central directory start. */ } else { // Non-split ZIP files, the disk number MUST be 0 $this->fwrite($this->fp, pack('V', 0)); } $this->fwrite($this->fp, pack('v', $this->totalFilesCount)); /* Total # of entries "on this disk". */ $this->fwrite($this->fp, pack('v', $this->totalFilesCount)); /* Total # of entries overall. */ $this->fwrite($this->fp, pack('V', $cdSize)); /* Size of central directory. */ $this->fwrite($this->fp, pack('V', $cdOffset)); /* Offset to start of central dir. */ // 2.0.b2 -- Write a ZIP file comment $this->fwrite($this->fp, pack('v', $comment_length)); /* ZIP file comment length. */ $this->fwrite($this->fp, $this->_comment); $this->fclose($this->fp); // If Split ZIP and there is no .zip file, rename the last fragment to .ZIP if ($this->useSplitArchive) { $extension = substr($this->_dataFileName, -3); if ($extension != '.zip') { Factory::getLog()->debug('Renaming last ZIP part to .ZIP extension'); $newName = $this->dataFileNameWithoutExtension . '.zip'; if (!@rename($this->_dataFileName, $newName)) { throw new RuntimeException('Could not rename last ZIP part to .ZIP extension.'); } $this->_dataFileName = $newName; } // If Split ZIP and only one fragment, change the signature if ($this->totalParts == 1) { $this->fp = $this->fopen($this->_dataFileName, 'r+'); $this->fwrite($this->fp, "\x50\x4b\x30\x30"); } } @chmod($this->_dataFileName, $this->getPermissions()); } /** * Returns a string with the extension (including the dot) of the files produced * by this class. * * @return string */ public function getExtension() { return '.zip'; } /** * Extend the bootstrap code to add some define's used by the ZIP format engine * * @return void */ protected function __bootstrap_code() { if (!defined('_AKEEBA_COMPRESSION_THRESHOLD')) { $config = Factory::getConfiguration(); define("_AKEEBA_COMPRESSION_THRESHOLD", $config->get('engine.archiver.common.big_file_threshold')); // Don't compress files over this size define("_AKEEBA_DIRECTORY_READ_CHUNK", $config->get('engine.archiver.zip.cd_glue_chunk_size')); // How much data to read at once when finalizing ZIP archives } parent::__bootstrap_code(); } /** * The most basic file transaction: add a single entry (file or directory) to * the archive. * * @param bool $isVirtual If true, the next parameter contains file data instead of a file name * @param string $sourceNameOrData Absolute file name to read data from or the file data itself is $isVirtual is * true * @param string $targetName The (relative) file name under which to store the file in the archive * * @return bool True on success, false otherwise */ protected function _addFile($isVirtual, &$sourceNameOrData, $targetName) { $configuration = Factory::getConfiguration(); // Note down the starting disk number for Split ZIP archives $starting_disk_number_for_this_file = 0; if ($this->useSplitArchive) { $starting_disk_number_for_this_file = $this->currentPartNumber - 1; } // Open data file for output $this->openArchiveForOutput(); // Should I continue backing up a file from the previous step? $continueProcessingFile = $configuration->get('volatile.engine.archiver.processingfile', false); // Initialize with the default values. Why are *these* values default? If we are continuing file packing, by // definition we have an uncompressed, non-virtual file. Hence the default values. $isDir = false; $isSymlink = false; $compressionMethod = 1; $zdata = null; // If we are continuing file packing we have an uncompressed, non-virtual file. $isVirtual = $continueProcessingFile ? false : $isVirtual; $resume = $continueProcessingFile ? 0 : null; if (!$continueProcessingFile) { // Log the file being added $messageSource = $isVirtual ? '(virtual data)' : "(source: $sourceNameOrData)"; Factory::getLog()->debug("-- Adding $targetName to archive $messageSource"); $this->writeFileHeader($sourceNameOrData, $targetName, $isVirtual, $isSymlink, $isDir, $compressionMethod, $zdata, $unc_len, $storedName, $crc, $c_len, $hexdtime, $old_offset); } else { // Since we are continuing archiving, it's an uncompressed regular file. Set up the variables. $sourceNameOrData = $configuration->get('volatile.engine.archiver.sourceNameOrData', ''); $resume = $configuration->get('volatile.engine.archiver.resume', 0); $unc_len = $configuration->get('volatile.engine.archiver.unc_len'); $storedName = $configuration->get('volatile.engine.archiver.storedName'); $crc = $configuration->get('volatile.engine.archiver.crc'); $c_len = $configuration->get('volatile.engine.archiver.c_len'); $hexdtime = $configuration->get('volatile.engine.archiver.hexdtime'); $old_offset = $configuration->get('volatile.engine.archiver.old_offset'); // Log the file we continue packing Factory::getLog()->debug("-- Resuming adding file $sourceNameOrData to archive from position $resume (total size $unc_len)"); } /* "File data" segment. */ if ($compressionMethod == 8) { $this->putRawDataIntoArchive($zdata); } elseif ($isVirtual) { // Virtual data. Put into the archive. $this->putRawDataIntoArchive($sourceNameOrData); } elseif ($isSymlink) { $this->fwrite($this->fp, @readlink($sourceNameOrData)); } elseif ((!$isDir) && (!$isSymlink)) { // Uncompressed file. if ($this->putUncompressedFileIntoArchive($sourceNameOrData, $unc_len, $resume) === true) { // If it returns true we are doing a step break to resume packing in the next step. So we need to return // true here to avoid running the final bit of code which writes the central directory record and // uncaches the file resume data. return true; } } // Open the central directory file for append if (is_null($this->cdfp)) { $this->cdfp = @$this->fopen($this->centralDirectoryFilename, "a"); } if ($this->cdfp === false) { throw new ErrorException("Could not open Central Directory temporary file for append!"); } $this->fwrite($this->cdfp, $this->centralDirectoryRecordStartSignature); if (!$isSymlink) { $this->fwrite($this->cdfp, "\x14\x00"); /* Version made by (always set to 2.0). */ $this->fwrite($this->cdfp, "\x14\x00"); /* Version needed to extract */ $this->fwrite($this->cdfp, pack('v', 2048)); /* General purpose bit flag */ $this->fwrite($this->cdfp, ($compressionMethod == 8) ? "\x08\x00" : "\x00\x00"); /* Compression method. */ } else { // Symlinks get special treatment $this->fwrite($this->cdfp, "\x14\x03"); /* Version made by (version 2.0 with UNIX extensions). */ $this->fwrite($this->cdfp, "\x0a\x03"); /* Version needed to extract */ $this->fwrite($this->cdfp, pack('v', 2048)); /* General purpose bit flag */ $this->fwrite($this->cdfp, "\x00\x00"); /* Compression method. */ } $this->fwrite($this->cdfp, $hexdtime); /* Last mod time/date. */ $this->fwrite($this->cdfp, $crc); /* CRC 32 information. */ $this->fwrite($this->cdfp, pack('V', $c_len)); /* Compressed filesize. */ if ($compressionMethod == 0) { // When we are not compressing, $unc_len is being reduced to 0 while backing up. // With this trick, we always store the correct length, as in this case the compressed // and uncompressed length is always the same. $this->fwrite($this->cdfp, pack('V', $c_len)); /* Uncompressed filesize. */ } else { // When compressing, the uncompressed length differs from compressed length // and this line writes the correct value. $this->fwrite($this->cdfp, pack('V', $unc_len)); /* Uncompressed filesize. */ } $fn_length = akstrlen($storedName); $this->fwrite($this->cdfp, pack('v', $fn_length)); /* Length of filename. */ $this->fwrite($this->cdfp, pack('v', 0)); /* Extra field length. */ $this->fwrite($this->cdfp, pack('v', 0)); /* File comment length. */ $this->fwrite($this->cdfp, pack('v', $starting_disk_number_for_this_file)); /* Disk number start. */ $this->fwrite($this->cdfp, pack('v', 0)); /* Internal file attributes. */ /* External file attributes */ if (!$isSymlink) { // Archive bit set $this->fwrite($this->cdfp, pack('V', $isDir ? 0x41FF0010 : 0xFE49FFE0)); } else { // For SymLinks we store UNIX file attributes $this->fwrite($this->cdfp, "\x20\x80\xFF\xA1"); } $this->fwrite($this->cdfp, pack('V', $old_offset)); /* Relative offset of local header. */ $this->fwrite($this->cdfp, $storedName); /* File name. */ /* Optional extra field, file comment goes here. */ // Finally, increase the file counter by one $this->totalFilesCount++; // Uncache data $configuration->set('volatile.engine.archiver.sourceNameOrData', null); $configuration->set('volatile.engine.archiver.unc_len', null); $configuration->set('volatile.engine.archiver.resume', null); $configuration->set('volatile.engine.archiver.hexdtime', null); $configuration->set('volatile.engine.archiver.crc', null); $configuration->set('volatile.engine.archiver.c_len', null); $configuration->set('volatile.engine.archiver.fn_length', null); $configuration->set('volatile.engine.archiver.old_offset', null); $configuration->set('volatile.engine.archiver.storedName', null); $configuration->set('volatile.engine.archiver.sourceNameOrData', null); $configuration->set('volatile.engine.archiver.processingfile', false); // ... and return TRUE = success return true; } /** * Write the file header before putting the file data into the archive * * @param string $sourceNameOrData The path to the file being compressed, or the raw file data for virtual files * @param string $targetName The target path to be stored inside the archive * @param bool $isVirtual Is this a virtual file? * @param bool $isSymlink Is this a symlink? * @param bool $isDir Is this a directory? * @param int $compressionMethod The compression method chosen for this file * @param string $zdata If we have compression method other than 0 this holds the compressed data. * We return that from this method to avoid having to compress the same data * twice (once to write the compressed data length in the header and once to * write the compressed data to the archive). * @param int $unc_len The uncompressed size of the file / source data * * @param string $storedName The file path stored in the archive * @param string $crc CRC-32 for the file * @param int $c_len Compressed data length * @param string $hexdtime ZIP's hexadecimal notation if the file's modification date * @param int $old_offset Offset of the file header in the part file */ protected function writeFileHeader(&$sourceNameOrData, $targetName, &$isVirtual, &$isSymlink, &$isDir, &$compressionMethod, &$zdata, &$unc_len, &$storedName, &$crc, &$c_len, &$hexdtime, &$old_offset) { static $memLimit = null; if (is_null($memLimit)) { $memLimit = $this->getMemoryLimit(); } $configuration = Factory::getConfiguration(); // See if it's a directory $isDir = $isVirtual ? false : is_dir($sourceNameOrData); // See if it's a symlink (w/out dereference) $isSymlink = false; if ($this->storeSymlinkTarget && !$isVirtual) { $isSymlink = is_link($sourceNameOrData); } // Get real size before compression [$unc_len, $fileModTime] = $this->getFileSizeAndModificationTime($sourceNameOrData, $isVirtual, $isSymlink, $isDir); // Decide if we will compress $compressionMethod = $this->getCompressionMethod($unc_len, $memLimit, $isDir, $isSymlink); if ($isVirtual) { Factory::getLog()->debug(' Virtual add:' . $targetName . ' (' . $unc_len . ') - ' . $compressionMethod); } /* "Local file header" segment. */ $crc = $this->getCRCForEntity($sourceNameOrData, $isVirtual, $isDir, $isSymlink); $storedName = $targetName; if (!$isSymlink && $isDir) { $storedName .= "/"; $unc_len = 0; } // Test for non-existing or unreadable files $this->testIfFileExists($sourceNameOrData, $isVirtual, $isDir, $isSymlink); // Default compressed (archived) length = uncompressed length – valid unless we can actually compress the data. $c_len = $unc_len; // If we have to compress, read the data in memory and compress it if ($compressionMethod == 8) { $this->getZData($sourceNameOrData, $isVirtual, $compressionMethod, $zdata, $unc_len, $c_len); // The method modifies $compressionMethod to 0 (uncompressed) or 1 (Deflate) but the ZIP format needs it // to be 0 (uncompressed) or 8 (Deflate). So I just multiply by 8. $compressionMethod *= 8; } // Get the hex time. $hexdtime = pack('V', $this->unix2DOSTime($fileModTime)); // If it's a split ZIP file, we've got to make sure that the header can fit in the part if ($this->useSplitArchive) { // Get header size, taking into account any extra header necessary $header_size = 30 + akstrlen($storedName); // Compare to free part space $free_space = $this->getPartFreeSize(); if ($free_space <= $header_size) { // Not enough space on current part, create new part $this->createAndOpenNewPart(); } } $old_offset = @ftell($this->fp); if ($this->useSplitArchive && ($old_offset == 0)) { // Because in split ZIPs we have the split ZIP marker in the first four bytes. @fseek($this->fp, 4); $old_offset = @ftell($this->fp); } // Get the file name length in bytes $fn_length = akstrlen($storedName); $this->fwrite($this->fp, $this->fileHeaderSignature); /* Begin creating the ZIP data. */ /* Version needed to extract. */ if (!$isSymlink) { $this->fwrite($this->fp, "\x14\x00"); } else { $this->fwrite($this->fp, "\x0a\x03"); } $this->fwrite($this->fp, pack('v', 2048)); /* General purpose bit flag. Bit 11 set = use UTF-8 encoding for filenames & comments */ $this->fwrite($this->fp, ($compressionMethod == 8) ? "\x08\x00" : "\x00\x00"); /* Compression method. */ $this->fwrite($this->fp, $hexdtime); /* Last modification time/date. */ $this->fwrite($this->fp, $crc); /* CRC 32 information. */ $this->fwrite($this->fp, pack('V', $c_len)); /* Compressed filesize. */ $this->fwrite($this->fp, pack('V', $unc_len)); /* Uncompressed filesize. */ $this->fwrite($this->fp, pack('v', $fn_length)); /* Length of filename. */ $this->fwrite($this->fp, pack('v', 0)); /* Extra field length. */ $this->fwrite($this->fp, $storedName); /* File name. */ // Cache useful information about the file if (!$isDir && !$isSymlink && !$isVirtual) { $configuration->set('volatile.engine.archiver.unc_len', $unc_len); $configuration->set('volatile.engine.archiver.hexdtime', $hexdtime); $configuration->set('volatile.engine.archiver.crc', $crc); $configuration->set('volatile.engine.archiver.c_len', $c_len); $configuration->set('volatile.engine.archiver.fn_length', $fn_length); $configuration->set('volatile.engine.archiver.old_offset', $old_offset); $configuration->set('volatile.engine.archiver.storedName', $storedName); $configuration->set('volatile.engine.archiver.sourceNameOrData', $sourceNameOrData); } } /** * Get the preferred compression method for a file * * @param int $fileSize File size in bytes * @param int $memLimit Memory limit in bytes * @param bool $isDir Is it a directory? * @param bool $isSymlink Is it a symlink? * * @return int Compression method to use */ protected function getCompressionMethod($fileSize, $memLimit, $isDir, $isSymlink) { // ZIP uses 0 for uncompressed and 8 for GZip Deflate whereas the parent method returns 0 and 1 respectively return 8 * parent::getCompressionMethod($fileSize, $memLimit, $isDir, $isSymlink); } /** * Calculate the CRC-32 checksum * * @param string $sourceNameOrData The path to the file being compressed, or the raw file data for virtual files * @param bool $isVirtual Is this a virtual file? * @param bool $isSymlink Is this a symlink? * @param bool $isDir Is this a directory? * * @return int The CRC-32 */ protected function getCRCForEntity(&$sourceNameOrData, &$isVirtual, &$isDir, &$isSymlink) { // No hash? No CRC32! if (!function_exists('hash')) { return pack('V', 0); } // Do I need to reverse the endianness of CRC32b data? static $reverseEndianness = null; if ($reverseEndianness === null) { $reverseEndianness = hash('crc32b', 'The quick brown fox jumped over the lazy dog.', true) === pack('N', 2191738434); } // Directories: dummy CRC-32 if (!$isSymlink && $isDir) { $crc = pack('V', 0); } // Symlinks: CRC32 of the link source elseif ($isSymlink) { $crc = hash('crc32b', @readlink($sourceNameOrData) ?: ''); } // Virtual files: CRC32 of the contents elseif ($isVirtual) { $crc = hash('crc32b', $sourceNameOrData ?: ''); } // Files: CRC32 of the file contents else { // Get the CRC32 for the file $crc = function_exists("hash_file") ? @hash_file('crc32b', $sourceNameOrData, true) : null; // If the file was unreadable skip it if ($crc === false) { throw new WarningException('Could not calculate CRC32 for ' . $sourceNameOrData . '. Looks like it is an unreadable file.'); } // If hash_file is not available use a fake CRC32 $crc = $crc ?: pack('V', 0); // Log the calculated CRC32 if the site is in debug mode if (defined('AKEEBADEBUG')) { $asHexChars = array_map( function ($c) { return dechex($c); }, unpack('C*', $crc) ); Factory::getLog()->debug( sprintf( "File %s - CRC32 = %s", $sourceNameOrData, implode('', $reverseEndianness ? array_reverse($asHexChars) : $asHexChars) ) ); } } /** * If CRC32 returns Big Endian data I'll have to convert it to Little Endian, as required by ZIP. * * I cannot unpack as Big Endian and repack as Little Endian. The intermediate conversion to integer might * overflow 32-bit versions of PHP as its internal integer type is platform-dependent. * * I cannot reverse the string using string functions because the internal character encoding may be something * other than ASCII / 8-bit and mb_string might not be available. * * Instead, I am unpacking the binary string as an array of unsigned bytes and then repacking the bytes, in * reverse order, into a binary string. pack() and unpack() are not affected by the character encoding. Using * unsigned bytes guarantees they will fit into internal integer variables regardless of the platform used. */ if ($crc !== "\000\000\000\000" && $reverseEndianness) { $temp = array_values(unpack('C4', $crc)); $crc = pack('C*', $temp[3], $temp[2], $temp[1], $temp[0]); } return $crc; } /** * Converts a UNIX timestamp to a 4-byte DOS date and time format * (date in high 2-bytes, time in low 2-bytes allowing magnitude * comparison). * * @param integer $unixtime The current UNIX timestamp. * * @return integer The current date in a 4-byte DOS format. */ protected function unix2DOSTime($unixtime = null) { $timearray = (is_null($unixtime)) ? getdate() : getdate($unixtime); if ($timearray['year'] < 1980) { $timearray['year'] = 1980; $timearray['mon'] = 1; $timearray['mday'] = 1; $timearray['hours'] = 0; $timearray['minutes'] = 0; $timearray['seconds'] = 0; } return (($timearray['year'] - 1980) << 25) | ($timearray['mon'] << 21) | ($timearray['mday'] << 16) | ($timearray['hours'] << 11) | ($timearray['minutes'] << 5) | ($timearray['seconds'] >> 1); } /** * Creates a new part for the spanned archive * * @param bool $finalPart Is this the final archive part? * * @return bool True on success */ protected function createNewPartFile($finalPart = false) { // Close any open file pointers if (is_resource($this->fp)) { $this->fclose($this->fp); } if (is_resource($this->cdfp)) { $this->fclose($this->cdfp); } // Remove the just finished part from the list of resumable offsets $this->removeFromOffsetsList($this->_dataFileName); // Set the file pointers to null $this->fp = null; $this->cdfp = null; // Push the previous part if we have to post-process it immediately $configuration = Factory::getConfiguration(); if ($configuration->get('engine.postproc.common.after_part', 0)) { $this->finishedPart[] = $this->_dataFileName; } // Add the part's size to our rolling sum clearstatcache(); $this->totalCompressedSize += filesize($this->_dataFileName); $this->totalParts++; $this->currentPartNumber = $this->totalParts; if ($finalPart) { $this->_dataFileName = $this->dataFileNameWithoutExtension . '.zip'; } else { $this->_dataFileName = $this->dataFileNameWithoutExtension . '.z' . sprintf('%02d', $this->currentPartNumber); } Factory::getLog()->info('Creating new ZIP part #' . $this->currentPartNumber . ', file ' . $this->_dataFileName); // Inform the backup engine that we have changed the multipart number $statistics = Factory::getStatistics(); $statistics->updateMultipart($this->totalParts); // Try to remove any existing file @unlink($this->_dataFileName); // Touch the new file $result = @touch($this->_dataFileName); @chmod($this->_dataFileName, $this->getPermissions()); return $result; } /** * Find the optimal chunk size for CRC32 calculations and file processing * * @return void */ private function findOptimalChunkSize() { $configuration = Factory::getConfiguration(); // The user has entered their own preference if ($configuration->get('engine.archiver.common.chunk_size', 0) > 0) { $this->AkeebaPackerZIP_CHUNK_SIZE = AKEEBA_CHUNK; return; } // Get the PHP memory limit $memLimit = $this->getMemoryLimit(); // Can't get a PHP memory limit? Use 2Mb chunks (fairly large, right?) if (is_null($memLimit)) { $this->AkeebaPackerZIP_CHUNK_SIZE = 2097152; return; } if (!function_exists("memory_get_usage")) { // PHP can't report memory usage, use a conservative 512Kb $this->AkeebaPackerZIP_CHUNK_SIZE = 524288; return; } // PHP *can* report memory usage, see if there's enough available memory $availableRAM = $memLimit - memory_get_usage(); if ($availableRAM > 0) { $this->AkeebaPackerZIP_CHUNK_SIZE = $availableRAM * 0.5; return; } // NEGATIVE AVAILABLE MEMORY?!! Some borked PHP implementations also return the size of the httpd footprint. if (($memLimit - 6291456) > 0) { $this->AkeebaPackerZIP_CHUNK_SIZE = $memLimit - 6291456; return; } // If all else fails, use 2Mb and cross your fingers $this->AkeebaPackerZIP_CHUNK_SIZE = 2097152; } /** * Create a Central Directory temporary file * * @return void * * @throws ErrorException */ private function createCentralDirectoryTempFile() { $configuration = Factory::getConfiguration(); $this->centralDirectoryFilename = tempnam($configuration->get('akeeba.basic.output_directory'), 'akzcd'); $this->centralDirectoryFilename = basename($this->centralDirectoryFilename); $pos = strrpos($this->centralDirectoryFilename, '/'); if ($pos !== false) { $this->centralDirectoryFilename = substr($this->centralDirectoryFilename, $pos + 1); } $pos = strrpos($this->centralDirectoryFilename, '\\'); if ($pos !== false) { $this->centralDirectoryFilename = substr($this->centralDirectoryFilename, $pos + 1); } $this->centralDirectoryFilename = Factory::getTempFiles()->registerTempFile($this->centralDirectoryFilename); Factory::getLog()->debug(__CLASS__ . " :: CntDir Tempfile = " . $this->centralDirectoryFilename); // Create temporary file if (!@touch($this->centralDirectoryFilename)) { throw new ErrorException("Could not open temporary file for ZIP archiver. Please check your temporary directory's permissions!"); } @chmod($this->centralDirectoryFilename, $this->getPermissions()); } }
