[gvfs] MTP: Fix crash when libmtp operations fails without error message.

[Philip Langdale <philipl src gnome org>]

commit 828a5cd1db7a352820f4979095389fb4a24e728f
Author: Philip Langdale <philipl overt org>
Date:   Mon Feb 11 07:46:56 2013 -0800

    MTP: Fix crash when libmtp operations fails without error message.

 daemon/gvfsbackendmtp.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)
---
diff --git a/daemon/gvfsbackendmtp.c b/daemon/gvfsbackendmtp.c
index efd1943..ba04028 100644
--- a/daemon/gvfsbackendmtp.c
+++ b/daemon/gvfsbackendmtp.c
@@ -280,14 +280,20 @@ emit_change_event (gpointer key,
 static void
 fail_job (GVfsJob *job, LIBMTP_mtpdevice_t *device)
 {
+  const char *text;
   LIBMTP_error_t *error = LIBMTP_Get_Errorstack (device);
 
+  if (error) {
+    text = g_strrstr (error->error_text, ":") + 1;
+  } else {
+    text = _("Unknown error.");
+  }
   g_vfs_job_failed (job, G_IO_ERROR,
                     g_vfs_job_is_cancelled (job) ?
                       G_IO_ERROR_CANCELLED :
                       G_IO_ERROR_FAILED,
                     _("libmtp error: %s"),
-                    g_strrstr (error->error_text, ":") + 1);
+                    text);
 
   LIBMTP_Clear_Errorstack (device);
 }