[gnome-software] trivial: Allow creating an empty cache dir

[Richard Hughes <rhughes src gnome org>]

commit ae0f7c6dbfc54bb8aeeed9a3f3733ddc98ab1337
Author: Richard Hughes <richard hughsie com>
Date:   Thu Jul 13 10:45:35 2017 +0100

    trivial: Allow creating an empty cache dir

 lib/gs-utils.c |    5 +++++
 lib/gs-utils.h |    7 ++++---
 2 files changed, 9 insertions(+), 3 deletions(-)
---
diff --git a/lib/gs-utils.c b/lib/gs-utils.c
index 0e051e3..be79b67 100644
--- a/lib/gs-utils.c
+++ b/lib/gs-utils.c
@@ -203,6 +203,11 @@ gs_utils_get_cache_filename (const gchar *kind,
                                     kind,
                                     NULL);
        cachedir_file = g_file_new_for_path (cachedir);
+       if (g_file_query_exists (cachedir_file, NULL) &&
+           flags & GS_UTILS_CACHE_FLAG_ENSURE_EMPTY) {
+               if (!gs_utils_rmtree (cachedir, error))
+                       return FALSE;
+       }
        if (!g_file_query_exists (cachedir_file, NULL) &&
            !g_file_make_directory_with_parents (cachedir_file, NULL, error))
                return NULL;
diff --git a/lib/gs-utils.h b/lib/gs-utils.h
index 17a0731..7d8cdab 100644
--- a/lib/gs-utils.h
+++ b/lib/gs-utils.h
@@ -37,9 +37,10 @@ G_BEGIN_DECLS
  * The cache flags.
  **/
 typedef enum {
-       GS_UTILS_CACHE_FLAG_NONE        = 0,
-       GS_UTILS_CACHE_FLAG_WRITEABLE   = 1 << 0,
-       GS_UTILS_CACHE_FLAG_USE_HASH    = 1 << 1,
+       GS_UTILS_CACHE_FLAG_NONE                = 0,
+       GS_UTILS_CACHE_FLAG_WRITEABLE           = 1 << 0,
+       GS_UTILS_CACHE_FLAG_USE_HASH            = 1 << 1,
+       GS_UTILS_CACHE_FLAG_ENSURE_EMPTY        = 1 << 2,
        /*< private >*/
        GS_UTILS_CACHE_FLAG_LAST
 } GsUtilsCacheFlags;