<?$a='';while($b=fread(STDIN,1))$a.=$b;if(1==$c=strlen($a))die("$a\n");for($d=2;$c>4*$d-4;$d++)$a.=" ";$f="array_fill";$e=$f(0,$d,$f(0,$d," "));$d--;for($f=0;$f<$d;$f++){$e[0][$f]=$a[$f];$e[$f][$d]=$a[$f+$d];$e[$d][$d-$f]=$a[$f+2*$d];$e[$d-$f][0]=$a[$f+3*$d];}foreach($e as$g)echo implode('',$g)."\n";
Note that non-ascii characters in the above source code will be escaped (such as \x9f).