[glib] simpleproxyresolver: Don't crash on invalid hostname

[Philip Withnall <pwithnall src gnome org>]

commit cb8c9199524d888bc2e354bbc05a5603b205d322
Author: Bastien Nocera <hadess hadess net>
Date:   Wed Dec 7 17:34:02 2016 +0100

    simpleproxyresolver: Don't crash on invalid hostname
    
    Check for g_hostname_to_ascii() failure, rather than crashing when
    checking whether an invalid hostname should go through the proxy.
    
    The HTTP library should report the error about the invalid hostname
    once we actually try to connect to it.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=772989

 gio/gsimpleproxyresolver.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/gio/gsimpleproxyresolver.c b/gio/gsimpleproxyresolver.c
index 145bd5e..8a6fb38 100644
--- a/gio/gsimpleproxyresolver.c
+++ b/gio/gsimpleproxyresolver.c
@@ -287,11 +287,13 @@ ignore_host (GSimpleProxyResolver *resolver,
 
   if (priv->ignore_domains)
     {
+      length = 0;
       if (g_hostname_is_non_ascii (host))
         host = ascii_host = g_hostname_to_ascii (host);
-      length = strlen (host);
+      if (host)
+        length = strlen (host);
 
-      for (i = 0; priv->ignore_domains[i].length; i++)
+      for (i = 0; length > 0 && priv->ignore_domains[i].length; i++)
        {
          GSimpleProxyResolverDomain *domain = &priv->ignore_domains[i];