function imcache($cachepath, $type, $function)
{
// Compose a uniqe'ish filename for cacheing.
$filename = urlencode($_SERVER["REQUEST_URI"]) . "---" . urlencode($function);
$filepath = realpath($cachepath)."/".$filename;
if(file_exists($filepath) and filectime($_SERVER["PATH_TRANSLATED"]) < filectime($filepath))
{
// if a file is there - stream response directly
header("Content-type: ".image_type_to_mime_type(exif_imagetype($filepath)));
@readfile($filepath);
touch($filepath);
}
else
{
// if a file isn't there - call function that wil generate image
// first make sure that $function "looks" like a function call
if(ereg("^\s*[_a-z0-9-]+\s*\(.*\)\s*;?\s*$", $function))
{
$im = FALSE;
// adjust function exspression ... (it needs to start with "$im = " and end with ";")
if(!(ereg(";\s*$", $function)))
$function = $function.";";
$function = '$im = '.$function;
// black magic ;-)
eval($function);
header ("Content-type: image/$type");
switch($type)
{
case "gif":
imagegif($im);
imagegif($im, $filepath);
break;
case "jpeg":
imagejpeg($im);
imagejpeg($im, $filepath);
break;
case "png":
imagepng($im);
imagepng($im, $filepath);
break;
}
imagedestroy($im);
}
else
{
trigger_error('imcache: $function argument not valid, must be in the form "foo(arg, arg)" on line '. __LINE__ ." in ". __FILE__);
}
}
}
?>