[gmime] Properly handle parser errors in basic-example.c

[Jeffrey Stedfast <fejj src gnome org>]

commit 9c610b076c510791bcbdeeb6547107957717473f
Author: Jeffrey Stedfast <jestedfa microsoft com>
Date:   Tue Sep 27 09:45:53 2016 -0400

    Properly handle parser errors in basic-example.c
    
    Patch by Hanno Boeck
    
    Fixes bug #772045

 examples/basic-example.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/examples/basic-example.c b/examples/basic-example.c
index 777a3bf..0fc1a70 100644
--- a/examples/basic-example.c
+++ b/examples/basic-example.c
@@ -316,6 +316,10 @@ int main (int argc, char **argv)
        
        /* parse the message */
        message = parse_message (fd);
+       if (message == NULL) {
+               printf("Error parsing message");
+               return 1;
+       }
        
        /* count the number of parts in the message */
        count_parts_in_message (message);