Php Programming Code Examples

Php > Graphics Code Examples

Im cache



Im cache

<?php

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__);
        }

    }
}

?>