db->pkgcache_loaded and db->grpcache_loaded

Clearly the old code was more elegant (NULL cache indicated "not loaded"),
but it had some drawbacks, so from now on we indicate the state of caches
explicitly.

Old drawbacks:
When we had an empty database (unstable), libalpm called db_populate after
every pkgcache access, because NULL pkgcache indicated "not loaded" state.
This is not a common case, but the same situation can happen with grpcache,
which is more problematic: If the user had a custom repo with no groups,
grpcache was always NULL. (grpcache is also loaded per database.) Thus
every get_grpcache call induced a load_grpcache operation, so the benefits
of grpcache was completely lost.

Signed-off-by: Nagy Gabor <ngaba@bibl.u-szeged.hu>
Signed-off-by: Dan McGee <dan@archlinux.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/lib/libalpm/db.h b/lib/libalpm/db.h
index 25b90b5f..edc4c93e 100644
--- a/lib/libalpm/db.h
+++ b/lib/libalpm/db.h
@@ -42,7 +42,9 @@ struct __pmdb_t {
 	char *path;
 	char *treename;
 	void *handle;
+	unsigned short pkgcache_loaded;
 	alpm_list_t *pkgcache;
+	unsigned short grpcache_loaded;
 	alpm_list_t *grpcache;
 	alpm_list_t *servers;
 };