thumb: ?backend option to override resize callback
[minimedit.git] / thumb / index.php
index b49ca6ef47be6270f485de9509f1387a8fe6676a..066e88d7cf9561227d96f8b6a2fe9ff80afacc21 100644 (file)
@@ -1,34 +1,69 @@
 <?php
 ob_clean();
 
-list ($height, $imgarg) = explode('/', ltrim($Args, '/'), 2);
+list ($height, $imgpath) = explode('/', ltrim($Args, '/'), 2);
 $width= 1000;
-$imgpath = "data/$imgarg";
+$imgpath = preg_replace('{^(?=[0-9]+/)}', 'data/', $imgpath, 1);
 
 if (!file_exists($imgpath)) {
        http_response_code(404);
-       exit;
+       $imgpath = '404.png';
+       if (!file_exists($imgpath)) {
+               exit;
+       }
 }
 
-$target = preg_replace("{^data/}", "thumb/$height/", $imgpath, 1);
+$target = "thumb/$height/$imgpath";
 if (!file_exists($target)) {
+       try {
+               mkthumb($imgpath, $target, $width, $height);
+       }
+       catch (Exception $e) {
+               http_response_code($e->getCode() ?: 500);
+               $target = '500.png';
+               if (file_exists($target)) {
+                       header("X-Error: ".$e->getMessage());
+                       header('Content-type: '.mime_content_type($target));
+                       readfile($target);
+                       exit;
+               }
+               trigger_error("thumbnail creation failed: ".$e->getMessage(), E_USER_WARNING);
+               exit;
+       }
+}
+
+header('Content-type: '.mime_content_type($target));
+readfile($target);
+exit;
+
+function mkthumb($source, $target, $width, $height)
+{
+       if (isset($_GET['backend'])) {
+               $backend = $_GET['backend'];
+       }
+       else {
+               $backend = 'exec';
+       }
+       $backend = "mkthumb_$backend";
+
        @mkdir(dirname($target), 0777, TRUE);
+       $backend($source, $target, $width, $height);
+}
 
+function mkthumb_exec($source, $target, $width, $height)
+{
+       if (!function_exists('popen')) {
+               throw new Exception("exec disallowed on this server", 501);
+       }
        $cmd = implode(' ', array_map('escapeshellarg', [
                'convert',
                '-trim',
                '-resize', "${width}x${height}",
                '-quality', '90%',
-               $imgpath, $target
+               $source, $target
        ]));
        $return = shell_exec("$cmd 2>&1");
        if ($return) {
-               http_response_code(500);
-               trigger_error("thumbnail creation failed: $return", E_USER_WARNING);
-               exit;
+               throw new Exception($return);
        }
 }
-
-header('Content-type: '.mime_content_type($target));
-readfile($target);
-exit;