[gnome-shell] app: Fix crash on search

[Ray Strode <halfline src gnome org>]

commit 46cea672586f0bd9d981ab4d456eb781577e3cec
Author: Ray Strode <rstrode redhat com>
Date:   Thu Nov 10 17:33:36 2011 -0500

    app: Fix crash on search
    
    Not all desktop files tracked by the shell have
    Exec lines.  This could be because they're actually
    run by another process, for instance, and the desktop
    file is merely there to provide metadata.  For example,
    nautilus-pastebin provides a desktop file without an
    Exec line.
    
    The shell currently crashes if one of these partial
    desktop files is installed and the user attempts to
    search from the overview.
    
    commit 37726a4cb69ab54298a3c95ccf469e1ab87ed4b1 fixed
    a similar crasher.
    
    This commit fixes the next one lower in the code.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=663815

 src/shell-app.c |   15 +++++++++------
 1 files changed, 9 insertions(+), 6 deletions(-)
---
diff --git a/src/shell-app.c b/src/shell-app.c
index 3d1e78a..54f81a0 100644
--- a/src/shell-app.c
+++ b/src/shell-app.c
@@ -1262,13 +1262,16 @@ _shell_app_match_search_terms (ShellApp  *app,
             current_match = MATCH_SUBSTRING;
         }
 
-      p = strstr (app->casefolded_exec, term);
-      if (p != NULL)
+      if (app->casefolded_exec)
         {
-          if (p == app->casefolded_exec || *(p - 1) == '-')
-            current_match = MATCH_PREFIX;
-          else if (current_match < MATCH_PREFIX)
-            current_match = MATCH_SUBSTRING;
+          p = strstr (app->casefolded_exec, term);
+          if (p != NULL)
+            {
+              if (p == app->casefolded_exec || *(p - 1) == '-')
+                current_match = MATCH_PREFIX;
+              else if (current_match < MATCH_PREFIX)
+                current_match = MATCH_SUBSTRING;
+            }
         }
 
       if (app->casefolded_description && current_match < MATCH_PREFIX)