Ticket #28077: 28077.diff

src/wp-admin/includes/image.php

@@ -259 +259 @@
         if ( ! file_exists( $file ) )
                 return false;
 
-        list( , , $sourceImageType ) = getimagesize( $file );
+        $sourceImageType = wp_get_image_type( $file );
 
         /*
          * EXIF contains a bunch of data we'll probably never need formatted in ways
@@ -430 +430 @@
 }
 
 /**
+ * Get the type of an image.
+ *
+ * This is the constant value for the image type, pass to
+ * image_type_to_mime_type() to get the mime type.
+ *
+ * @param string $path File path to the image
+ * @return string MIME type of the image
+ */
+function wp_get_image_type( $path ) {
+        if ( is_callable( 'exif_imagetype' ) ) {
+                return @exif_imagetype( $path );
+        }
+
+        /**
+         * In the case of exif_imagetype not being available, we use the
+         * slower more network heavy getimagesize
+         */
+        $size = @getimagesize( $file );
+
+        return $size[2];
+}
+
+/**
  * Validate that file is an image.
  *
  * @since 2.5.0
@@ -453 +476 @@
 function file_is_displayable_image($path) {
         $displayable_image_types = array( IMAGETYPE_GIF, IMAGETYPE_JPEG, IMAGETYPE_PNG, IMAGETYPE_BMP );
 
-        $info = @getimagesize( $path );
-        if ( empty( $info ) ) {
-                $result = false;
-        } elseif ( ! in_array( $info[2], $displayable_image_types ) ) {
-                $result = false;
-        } else {
-                $result = true;
-        }
+        $result = in_array( wp_get_image_type( $path ), $displayable_image_types );
 
         /**
          * Filter whether the current image is displayable in the browser.

src/wp-includes/functions.php

@@ -2181 +2181 @@
         }
 
         // We're able to validate images using GD
-        if ( $type && 0 === strpos( $type, 'image/' ) && function_exists('getimagesize') ) {
+        if ( $type && 0 === strpos( $type, 'image/' ) ) {
 
-                // Attempt to figure out what type of image it actually is
-                $imgstats = @getimagesize( $file );
+                $image_mime_type = wp_get_image_type( $file );
 
-                // If getimagesize() knows what kind of image it really is and if the real MIME doesn't match the claimed MIME
-                if ( !empty($imgstats['mime']) && $imgstats['mime'] != $type ) {
+                // If the real MIME doesn't match the claimed MIME
+                if ( $image_mime_type != $type ) {
                         /**
                          * Filter the list mapping image mime types to their respective extensions.
                          *
@@ -2204 +2203 @@
                         ) );
 
                         // Replace whatever is after the last period in the filename with the correct extension
-                        if ( ! empty( $mime_to_ext[ $imgstats['mime'] ] ) ) {
+                        if ( ! empty( $mime_to_ext[ $image_mime_type ] ) ) {
                                 $filename_parts = explode( '.', $filename );
                                 array_pop( $filename_parts );
-                                $filename_parts[] = $mime_to_ext[ $imgstats['mime'] ];
+                                $filename_parts[] = $mime_to_ext[ $image_mime_type ];
                                 $new_filename = implode( '.', $filename_parts );
 
                                 if ( $new_filename != $filename ) {

tests/phpunit/tests/image/functions.php

@@ -351 +351 @@
                 remove_filter( 'wp_image_editors', array( $this, 'mock_image_editor' ) );
                 WP_Image_Editor_Mock::$save_return = array();
         }
+
+        public function test_wp_get_image_type() {
+
+                $image_paths = array(
+                        DIR_TESTDATA . '/images/test-image.jpg' => IMAGETYPE_JPEG,
+                        DIR_TESTDATA . '/images/test-image.png' => IMAGETYPE_PNG,
+                        DIR_TESTDATA . '/images/test-image.tiff' => IMAGETYPE_TIFF_MM,
+                        DIR_TESTDATA . '/images/test-image.jp2' => IMAGETYPE_JP2,
+                        DIR_TESTDATA . '/images/test-image.bmp' => IMAGETYPE_BMP,
+                        DIR_TESTDATA . '/images/test-image.gif' => IMAGETYPE_GIF,
+                );
+
+                foreach ( $image_paths as $image_path => $type ) {
+                        // use getimagesize as a comparison, as it needs to be compatibile
+                        $info = getimagesize( $image_path );
+                        $this->assertEquals( $info[2], wp_get_image_type( $image_path ), 'getimagesize() returns different result for ' . $image_path );
+
+                        $this->assertEquals( $type, wp_get_image_type( $image_path ), 'Image type incorrect for ' . $image_path );
+                }
+
+                $this->assertEquals( false, wp_get_image_type( '/some/broken/path' ) );
+        }
 }