Creating Zip file using PHP

A useful code to create a zip file from the PHP. I used it in WAP site generator and it worked on first take.
< ?php class zipfile { var $datasec = array(); var $ctrl_dir = array(); var $eof_ctrl_dir = "\x50\x4b\x05\x06\x00\x00\x00\x00"; var $old_offset = 0; function add_dir($name) { $name = str_replace("", "/", $name); $fr = "\x50\x4b\x03\x04"; $fr .= "\x0a\x00"; $fr .= "\x00\x00"; $fr .= "\x00\x00"; $fr .= "\x00\x00\x00\x00"; $fr .= pack("V",0); $fr .= pack("V",0); $fr .= pack("V",0); $fr .= pack("v", strlen($name) ); $fr .= pack("v", 0 ); $fr .= $name; $fr .= pack("V", 0); $fr .= pack("V", 0); $fr .= pack("V", 0); $this -> datasec[] = $fr;
$new_offset = strlen(implode(”", $this->datasec));
$cdrec = “\x50\x4b\x01\x02″;
$cdrec .=”\x00\x00″;
$cdrec .=”\x0a\x00″;
$cdrec .=”\x00\x00″;
$cdrec .=”\x00\x00″;
$cdrec .=”\x00\x00\x00\x00″;
$cdrec .= pack(”V”,0);
$cdrec .= pack(”V”,0);
$cdrec .= pack(”V”,0);
$cdrec .= pack(”v”, strlen($name) );
$cdrec .= pack(”v”, 0 );
$cdrec .= pack(”v”, 0 );
$cdrec .= pack(”v”, 0 );
$cdrec .= pack(”v”, 0 );
$ext = “\x00\x00\x10\x00″;
$ext = “\xff\xff\xff\xff”;
$cdrec .= pack(”V”, 16 );
$cdrec .= pack(”V”, $this -> old_offset );
$cdrec .= $name;
$this -> ctrl_dir[] = $cdrec;
$this -> old_offset = $new_offset;
return;
}

function add_file($data, $name)
{
$fp = fopen($data,”r”);
$data = fread($fp,filesize($data));
fclose($fp);
$name = str_replace(”", “/”, $name);
$unc_len = strlen($data);
$crc = crc32($data);
$zdata = gzcompress($data);
$zdata = substr ($zdata, 2, -4);
$c_len = strlen($zdata);
$fr = “\x50\x4b\x03\x04″;
$fr .= “\x14\x00″;
$fr .= “\x00\x00″;
$fr .= “\x08\x00″;
$fr .= “\x00\x00\x00\x00″;
$fr .= pack(”V”,$crc);
$fr .= pack(”V”,$c_len);
$fr .= pack(”V”,$unc_len);
$fr .= pack(”v”, strlen($name) );
$fr .= pack(”v”, 0 );
$fr .= $name;
$fr .= $zdata;
$fr .= pack(”V”,$crc);
$fr .= pack(”V”,$c_len);
$fr .= pack(”V”,$unc_len);
$this -> datasec[] = $fr;
$new_offset = strlen(implode(”", $this->datasec));
$cdrec = “\x50\x4b\x01\x02″;
$cdrec .=”\x00\x00″;
$cdrec .=”\x14\x00″;
$cdrec .=”\x00\x00″;
$cdrec .=”\x08\x00″;
$cdrec .=”\x00\x00\x00\x00″;
$cdrec .= pack(”V”,$crc);
$cdrec .= pack(”V”,$c_len);
$cdrec .= pack(”V”,$unc_len);
$cdrec .= pack(”v”, strlen($name) );
$cdrec .= pack(”v”, 0 );
$cdrec .= pack(”v”, 0 );
$cdrec .= pack(”v”, 0 );
$cdrec .= pack(”v”, 0 );
$cdrec .= pack(”V”, 32 );
$cdrec .= pack(”V”, $this -> old_offset );
$this -> old_offset = $new_offset;
$cdrec .= $name;
$this -> ctrl_dir[] = $cdrec;
}
function file() {
$data = implode(”", $this -> datasec);
$ctrldir = implode(”", $this -> ctrl_dir);
return $data . $ctrldir . $this -> eof_ctrl_dir . pack(”v”, sizeof($this -> ctrl_dir)) .
pack(”v”, sizeof($this -> ctrl_dir)) . pack(”V”, strlen($ctrldir)) .
pack(”V”, strlen ( $data)) . “\x00\x00″;
}
}
// Test this class
$zipTest = new zipfile();
$zipTest->add_dir(”images/”);
$zipTest->add_file(”images/box1.jpg”, “images/box1.jpg”);
$zipTest->add_file(”images/box2.jpg”, “images/box2.jpg”);
// Return Zip File to Browser
Header(”Content-type: application/octet-stream”);
Header (”Content-disposition: attachment; filename=zipTest.zip”);
echo $zipTest->file();
// Alternatively, you can write the file to the file system and provide a link:
/*
$filename = “output.zip”;
$fd = fopen ($filename, “wb”);
$out = fwrite ($fd, $zipTest -> file());
fclose ($fd);
echo “Click here to download the new zip file.“;
*/
?>