[gdk-pixbuf] thumbnailer: Avoid runtime warnings when file_to_pixbuf() fails

[Bastien Nocera <hadess src gnome org>]

commit ca523901a4dd7c4e503d857e83e7a0375d632f2a
Author: Bastien Nocera <hadess hadess net>
Date:   Mon Dec 12 17:20:27 2016 +0100

    thumbnailer: Avoid runtime warnings when file_to_pixbuf() fails
    
    By updating the thumbnailer skeleton.

 thumbnailer/gnome-thumbnailer-skeleton.c |   41 ++++++++++++++++--------------
 1 files changed, 22 insertions(+), 19 deletions(-)
---
diff --git a/thumbnailer/gnome-thumbnailer-skeleton.c b/thumbnailer/gnome-thumbnailer-skeleton.c
index 6224bec..812b584 100644
--- a/thumbnailer/gnome-thumbnailer-skeleton.c
+++ b/thumbnailer/gnome-thumbnailer-skeleton.c
@@ -225,7 +225,7 @@ int main (int argc, char **argv)
        const char *output;
 
 #ifdef THUMBNAILER_RETURNS_PIXBUF
-       int width, height;
+       /* Nothing */
 #elif THUMBNAILER_RETURNS_DATA
        char *data = NULL;
        gsize length;
@@ -270,24 +270,27 @@ int main (int argc, char **argv)
 
 #ifdef THUMBNAILER_RETURNS_PIXBUF
        pixbuf = file_to_pixbuf (input_filename, output_size, &error);
-
-       width = gdk_pixbuf_get_width (pixbuf);
-       height = gdk_pixbuf_get_height (pixbuf);
-
-       /* Handle naive thumbnailers that don't resize */
-       if (output_size != 0 &&
-           (height > output_size || width > output_size)) {
-               GdkPixbuf *scaled;
-               double scale;
-
-               scale = (double)output_size / MAX (width, height);
-
-               scaled = gnome_desktop_thumbnail_scale_down_pixbuf (pixbuf,
-                                                                   floor (width * scale + 0.5),
-                                                                   floor (height * scale + 0.5));
-               gdk_pixbuf_copy_options (pixbuf, scaled);
-               g_object_unref (pixbuf);
-               pixbuf = scaled;
+       if (pixbuf != NULL) {
+               int width, height;
+
+               width = gdk_pixbuf_get_width (pixbuf);
+               height = gdk_pixbuf_get_height (pixbuf);
+
+               /* Handle naive thumbnailers that don't resize */
+               if (output_size != 0 &&
+                   (height > output_size || width > output_size)) {
+                       GdkPixbuf *scaled;
+                       double scale;
+
+                       scale = (double)output_size / MAX (width, height);
+
+                       scaled = gnome_desktop_thumbnail_scale_down_pixbuf (pixbuf,
+                                                                           floor (width * scale + 0.5),
+                                                                           floor (height * scale + 0.5));
+                       gdk_pixbuf_copy_options (pixbuf, scaled);
+                       g_object_unref (pixbuf);
+                       pixbuf = scaled;
+               }
        }
 #elif THUMBNAILER_RETURNS_DATA
        data = file_to_data (input_filename, &length, &error);