Description: This class reads and writes Tape-Archive (TAR) Files and Gzip compressed TAR files, which are mainly used on UNIX systems. This class works on both windows AND unix systems, and does NOT rely on external applications!! Woohoo! Usage: Copyright (C) 2002 Josh Barger This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library 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 Lesser General Public License for more details at: http://www.gnu.org/copyleft/lesser.html If you use this script in your application/website, please send me an e-mail letting me know about it :) Bugs: Please report any bugs you might find to my e-mail address at joshb@npt.com. If you have already created a fix/patch for the bug, please do send it to me so I can incorporate it into my release. Version History: 1.0 04/10/2002 - InitialRelease 2.0 04/11/2002 - Merged both tarReader and tarWriter classes into one - Added support for gzipped tar files Remember to name for .tar.gz or .tgz if you use gzip compression! :: THIS REQUIRES ZLIB EXTENSION :: - Added additional comments to functions to help users - Added ability to remove files and directories from archive 2.1 04/12/2002 - Fixed serious bug in generating tar - Created another example file - Added check to make sure ZLIB is installed before running GZIP compression on TAR 2.2 05/07/2002 - Added automatic detection of Gzipped tar files (Thanks go to Jürgen Falch for the idea) - Changed "private" functions to have special function names beginning with two underscores ======================================================================= */ class tar { // Unprocessed Archive Information var $filename; var $isGzipped; var $tar_file; // Processed Archive Information var $files; var $directories; var $numFiles; var $numDirectories; // Class Constructor -- Does nothing... function tar() { return true; } // Computes the unsigned Checksum of a file's header // to try to ensure valid file // PRIVATE ACCESS FUNCTION function __computeUnsignedChecksum($bytestring) { for($i=0; $i<512; $i++) $unsigned_chksum += ord($bytestring[$i]); for($i=0; $i<8; $i++) $unsigned_chksum -= ord($bytestring[148 + $i]); $unsigned_chksum += ord(" ") * 8; return $unsigned_chksum; } // Converts a NULL padded string to a non-NULL padded string // PRIVATE ACCESS FUNCTION function __parseNullPaddedString($string) { $position = strpos($string,chr(0)); return substr($string,0,$position); } // This function parses the current TAR file // PRIVATE ACCESS FUNCTION function __parseTar() { // Read Files from archive $tar_length = strlen($this->tar_file); $main_offset = 0; while($main_offset < $tar_length) { // If we read a block of 512 nulls, we are at the end of the archive if(substr($this->tar_file,$main_offset,512) == str_repeat(chr(0),512)) break; // Parse file name $file_name = $this->__parseNullPaddedString(substr($this->tar_file,$main_offset,100)); // Parse the file mode $file_mode = substr($this->tar_file,$main_offset + 100,8); // Parse the file user ID $file_uid = octdec(substr($this->tar_file,$main_offset + 108,8)); // Parse the file group ID $file_gid = octdec(substr($this->tar_file,$main_offset + 116,8)); // Parse the file size $file_size = octdec(substr($this->tar_file,$main_offset + 124,12)); // Parse the file update time - unix timestamp format $file_time = octdec(substr($this->tar_file,$main_offset + 136,12)); // Parse Checksum $file_chksum = octdec(substr($this->tar_file,$main_offset + 148,6)); // Parse user name $file_uname = $this->__parseNullPaddedString(substr($this->tar_file,$main_offset + 265,32)); // Parse Group name $file_gname = $this->__parseNullPaddedString(substr($this->tar_file,$main_offset + 297,32)); // Make sure our file is valid if($this->__computeUnsignedChecksum(substr($this->tar_file,$main_offset,512)) != $file_chksum) return false; // Parse File Contents $file_contents = substr($this->tar_file,$main_offset + 512,$file_size); /* ### Unused Header Information ### $activeFile["typeflag"] = substr($this->tar_file,$main_offset + 156,1); $activeFile["linkname"] = substr($this->tar_file,$main_offset + 157,100); $activeFile["magic"] = substr($this->tar_file,$main_offset + 257,6); $activeFile["version"] = substr($this->tar_file,$main_offset + 263,2); $activeFile["devmajor"] = substr($this->tar_file,$main_offset + 329,8); $activeFile["devminor"] = substr($this->tar_file,$main_offset + 337,8); $activeFile["prefix"] = substr($this->tar_file,$main_offset + 345,155); $activeFile["endheader"] = substr($this->tar_file,$main_offset + 500,12); */ if($file_size > 0) { // Increment number of files $this->numFiles++; // Create us a new file in our array $activeFile = &$this->files[]; // Asign Values $activeFile["name"] = $file_name; $activeFile["mode"] = $file_mode; $activeFile["size"] = $file_size; $activeFile["time"] = $file_time; $activeFile["user_id"] = $file_uid; $activeFile["group_id"] = $file_gid; $activeFile["user_name"] = $file_uname; $activeFile["group_name"] = $file_gname; $activeFile["checksum"] = $file_chksum; $activeFile["file"] = $file_contents; } else { // Increment number of directories $this->numDirectories++; // Create a new directory in our array $activeDir = &$this->directories[]; // Assign values $activeDir["name"] = $file_name; $activeDir["mode"] = $file_mode; $activeDir["time"] = $file_time; $activeDir["user_id"] = $file_uid; $activeDir["group_id"] = $file_gid; $activeDir["user_name"] = $file_uname; $activeDir["group_name"] = $file_gname; $activeDir["checksum"] = $file_chksum; } // Move our offset the number of blocks we have processed $main_offset += 512 + (ceil($file_size / 512) * 512); } return true; } // Read a non gzipped tar file in for processing // PRIVATE ACCESS FUNCTION function __readTar($filename='') { // Set the filename to load if(!$filename) $filename = $this->filename; // Read in the TAR file $fp = fopen($filename,"rb"); $this->tar_file = fread($fp,filesize($filename)); fclose($fp); if($this->tar_file[0] == chr(31) && $this->tar_file[1] == chr(139) && $this->tar_file[2] == chr(8)) { if(!function_exists("gzinflate")) return false; $this->isGzipped = TRUE; $this->tar_file = gzinflate(substr($this->tar_file,10,-4)); } // Parse the TAR file $this->__parseTar(); return true; } // Generates a TAR file from the processed data // PRIVATE ACCESS FUNCTION function __generateTAR() { // Clear any data currently in $this->tar_file unset($this->tar_file); // Generate Records for each directory, if we have directories if($this->numDirectories > 0) { foreach($this->directories as $key => $information) { unset($header); // Generate tar header for this directory // Filename, Permissions, UID, GID, size, Time, checksum, typeflag, linkname, magic, version, user name, group name, devmajor, devminor, prefix, end $header .= str_pad($information["name"],100,chr(0)); $header .= str_pad(decoct($information["mode"]),7,"0",STR_PAD_LEFT) . chr(0); $header .= str_pad(decoct($information["user_id"]),7,"0",STR_PAD_LEFT) . chr(0); $header .= str_pad(decoct($information["group_id"]),7,"0",STR_PAD_LEFT) . chr(0); $header .= str_pad(decoct(0),11,"0",STR_PAD_LEFT) . chr(0); $header .= str_pad(decoct($information["time"]),11,"0",STR_PAD_LEFT) . chr(0); $header .= str_repeat(" ",8); $header .= "5"; $header .= str_repeat(chr(0),100); $header .= str_pad("ustar",6,chr(32)); $header .= chr(32) . chr(0); $header .= str_pad("",32,chr(0)); $header .= str_pad("",32,chr(0)); $header .= str_repeat(chr(0),8); $header .= str_repeat(chr(0),8); $header .= str_repeat(chr(0),155); $header .= str_repeat(chr(0),12); // Compute header checksum $checksum = str_pad(decoct($this->__computeUnsignedChecksum($header)),6,"0",STR_PAD_LEFT); for($i=0; $i<6; $i++) { $header[(148 + $i)] = substr($checksum,$i,1); } $header[154] = chr(0); $header[155] = chr(32); // Add new tar formatted data to tar file contents $this->tar_file .= $header; } } // Generate Records for each file, if we have files (We should...) if($this->numFiles > 0) { foreach($this->files as $key => $information) { unset($header); // Generate the TAR header for this file // Filename, Permissions, UID, GID, size, Time, checksum, typeflag, linkname, magic, version, user name, group name, devmajor, devminor, prefix, end $header .= str_pad($information["name"],100,chr(0)); $header .= str_pad(decoct($information["mode"]),7,"0",STR_PAD_LEFT) . chr(0); $header .= str_pad(decoct($information["user_id"]),7,"0",STR_PAD_LEFT) . chr(0); $header .= str_pad(decoct($information["group_id"]),7,"0",STR_PAD_LEFT) . chr(0); $header .= str_pad(decoct($information["size"]),11,"0",STR_PAD_LEFT) . chr(0); $header .= str_pad(decoct($information["time"]),11,"0",STR_PAD_LEFT) . chr(0); $header .= str_repeat(" ",8); $header .= "0"; $header .= str_repeat(chr(0),100); $header .= str_pad("ustar",6,chr(32)); $header .= chr(32) . chr(0); $header .= str_pad($information["user_name"],32,chr(0)); // How do I get a file's user name from PHP? $header .= str_pad($information["group_name"],32,chr(0)); // How do I get a file's group name from PHP? $header .= str_repeat(chr(0),8); $header .= str_repeat(chr(0),8); $header .= str_repeat(chr(0),155); $header .= str_repeat(chr(0),12); // Compute header checksum $checksum = str_pad(decoct($this->__computeUnsignedChecksum($header)),6,"0",STR_PAD_LEFT); for($i=0; $i<6; $i++) { $header[(148 + $i)] = substr($checksum,$i,1); } $header[154] = chr(0); $header[155] = chr(32); // Pad file contents to byte count divisible by 512 $file_contents = str_pad($information["file"],(ceil($information["size"] / 512) * 512),chr(0)); // Add new tar formatted data to tar file contents $this->tar_file .= $header . $file_contents; } } // Add 512 bytes of NULLs to designate EOF $this->tar_file .= str_repeat(chr(0),512); return true; } // Open a TAR file function openTAR($filename) { // Clear any values from previous tar archives unset($this->filename); unset($this->isGzipped); unset($this->tar_file); unset($this->files); unset($this->directories); unset($this->numFiles); unset($this->numDirectories); // If the tar file doesn't exist... if(!file_exists($filename)) return false; $this->filename = $filename; // Parse this file $this->__readTar(); return true; } // Appends a tar file to the end of the currently opened tar file function appendTar($filename) { // If the tar file doesn't exist... if(!file_exists($filename)) return false; $this->__readTar($filename); return true; } // Retrieves information about a file in the current tar archive function getFile($filename) { if($this->numFiles > 0) { foreach($this->files as $key => $information) { if($information["name"] == $filename) return $information; } } return false; } // Retrieves information about a directory in the current tar archive function getDirectory($dirname) { if($this->numDirectories > 0) { foreach($this->directories as $key => $information) { if($information["name"] == $dirname) return $information; } } return false; } // Check if this tar archive contains a specific file function containsFile($filename) { if($this->numFiles > 0) { foreach($this->files as $key => $information) { if($information["name"] == $filename) return true; } } return false; } // Check if this tar archive contains a specific directory function containsDirectory($dirname) { if($this->numDirectories > 0) { foreach($this->directories as $key => $information) { if($information["name"] == $dirname) return true; } } return false; } // Add a directory to this tar archive function addDirectory($dirname) { if(!file_exists($dirname)) return false; // Get directory information $file_information = stat($dirname); // Add directory to processed data $this->numDirectories++; $activeDir = &$this->directories[]; $activeDir["name"] = $dirname; $activeDir["mode"] = $file_information["mode"]; $activeDir["time"] = $file_information["time"]; $activeDir["user_id"] = $file_information["uid"]; $activeDir["group_id"] = $file_information["gid"]; $activeDir["checksum"] = $checksum; return true; } // Add a file to the tar archive function addFile($filename) { // Make sure the file we are adding exists! if(!file_exists($filename)) return false; // Make sure there are no other files in the archive that have this same filename if($this->containsFile($filename)) return false; // Get file information $file_information = stat($filename); // Read in the file's contents $fp = fopen($filename,"rb"); $file_contents = fread($fp,filesize($filename)); fclose($fp); // Add file to processed data $this->numFiles++; $activeFile = &$this->files[]; $activeFile["name"] = $filename; $activeFile["mode"] = $file_information["mode"]; $activeFile["user_id"] = $file_information["uid"]; $activeFile["group_id"] = $file_information["gid"]; $activeFile["size"] = $file_information["size"]; $activeFile["time"] = $file_information["mtime"]; $activeFile["checksum"] = $checksum; $activeFile["user_name"] = ""; $activeFile["group_name"] = ""; $activeFile["file"] = $file_contents; return true; } // Remove a file from the tar archive function removeFile($filename) { if($this->numFiles > 0) { foreach($this->files as $key => $information) { if($information["name"] == $filename) { $this->numFiles--; unset($this->files[$key]); return true; } } } return false; } // Remove a directory from the tar archive function removeDirectory($dirname) { if($this->numDirectories > 0) { foreach($this->directories as $key => $information) { if($information["name"] == $dirname) { $this->numDirectories--; unset($this->directories[$key]); return true; } } } return false; } // Write the currently loaded tar archive to disk function saveTar() { if(!$this->filename) return false; // Write tar to current file using specified gzip compression $this->toTar($this->filename,$this->isGzipped); return true; } // Saves tar archive to a different file than the current file function toTar($filename,$useGzip) { if(!$filename) return false; // Encode processed files into TAR file format $this->__generateTar(); // GZ Compress the data if we need to if($useGzip) { // Make sure we have gzip support if(!function_exists("gzencode")) return false; $file = gzencode($this->tar_file); } else { $file = $this->tar_file; } // Write the TAR file $fp = fopen($filename,"wb"); fwrite($fp,$file); fclose($fp); return true; } } ?>