Fix extension-swapping code for files that have extensions that are

not 3 characters long.  Fixes #1845.

2 files changed, 13 insertions, 1 deletions

diff --git a/modules/gallery/helpers/graphics.php b/modules/gallery/helpers/graphics.php
index 7e0bbbea..27ee124a 100644
--- a/modules/gallery/helpers/graphics.php
+++ b/modules/gallery/helpers/graphics.php
@@ -156,7 +156,7 @@ class graphics_Core {
       foreach ($ops as $target => $output_file) {
         if ($input_item->is_movie()) {
           // Convert the movie to a JPG first
-          $output_file = preg_replace("/...$/", "jpg", $output_file);
+          $output_file = legal_file::change_extension($output_file, "jpg");
           try {
             movie::extract_frame($input_file, $output_file);
           } catch (Exception $e) {
diff --git a/modules/gallery/helpers/legal_file.php b/modules/gallery/helpers/legal_file.php
index 6ec65e97..af6472ca 100644
--- a/modules/gallery/helpers/legal_file.php
+++ b/modules/gallery/helpers/legal_file.php
@@ -80,4 +80,16 @@ class legal_file_Core {
     module::event("legal_movie_types", $types_wrapper);
     return $types_wrapper->types;
   }
+
+  /**
+   * Convert the extension of a filename.  If the original filename has no
+   * extension, add the new one to the end.
+   */
+  static function change_extension($filename, $new_ext) {
+    if (strpos($filename, ".") === false) {
+      return "{$filename}.{$new_ext}";
+    } else {
+      return preg_replace("/\..*?$/", ".{$new_ext}", $filename);
+    }
+  }
 }