libalpm: introduce a usage level for repos

This defines a level of interest a user has in a repository. These are
described by the bitmask flags in the alpm_db_usage_t enum:

  ALPM_DB_USAGE_SEARCH: repo is valid for searching
  ALPM_DB_USAGE_INSTALL: repo is valid for installs (e.g. -S pkg)
  ALPM_DB_USAGE_UPGRADE: repo is valid for sysupgrades
  ALPM_DB_USAGE_ALL: all of the above are valid

Explicitly listing the contents of a repo will always be valid, and the
repo will always be refreshed appropriately on sync operations.

Signed-off-by: Dave Reisner <dreisner@archlinux.org>
Signed-off-by: Allan McRae <allan@archlinux.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/lib/libalpm/be_sync.c b/lib/libalpm/be_sync.c
index 0b996843..123d9539 100644
--- a/lib/libalpm/be_sync.c
+++ b/lib/libalpm/be_sync.c
@@ -183,6 +183,10 @@ int SYMEXPORT alpm_db_update(int force, alpm_db_t *db)
 	ASSERT(db != handle->db_local, RET_ERR(handle, ALPM_ERR_WRONG_ARGS, -1));
 	ASSERT(db->servers != NULL, RET_ERR(handle, ALPM_ERR_SERVER_NONE, -1));
 
+	if(!(db->usage & ALPM_DB_USAGE_SYNC)) {
+		return 0;
+	}
+
 	syncpath = get_sync_dir(handle);
 	if(!syncpath) {
 		return -1;