Define range of GIDs for cached app data.
To support upcoming disk usage calculation optimizations, this change
creates a new GID for each app that will be used to mark its cached
data. We're allocating these unique GIDs so that we can use
quotactl() to track cached data on a per-app basis.
This change also tightens up the implementation of both the cache
and shared GID calculation to ensure that they stay inside the valid
ranges, and includes tests to verify.
Test: builds, boots, tests pass
Bug: 27948817
Change-Id: Ie4377e5aae267f2da39a165888139228995987cb
diff --git a/include/cutils/multiuser.h b/include/cutils/multiuser.h
index 7e7f815..4f23776 100644
--- a/include/cutils/multiuser.h
+++ b/include/cutils/multiuser.h
@@ -23,19 +23,19 @@
extern "C" {
#endif
-// NOTE: keep in sync with android.os.UserId
-
-#define MULTIUSER_APP_PER_USER_RANGE 100000
-#define MULTIUSER_FIRST_SHARED_APPLICATION_GID 50000
-#define MULTIUSER_FIRST_APPLICATION_UID 10000
-
typedef uid_t userid_t;
typedef uid_t appid_t;
extern userid_t multiuser_get_user_id(uid_t uid);
extern appid_t multiuser_get_app_id(uid_t uid);
-extern uid_t multiuser_get_uid(userid_t userId, appid_t appId);
-extern appid_t multiuser_get_shared_app_gid(uid_t uid);
+
+extern uid_t multiuser_get_uid(userid_t user_id, appid_t app_id);
+
+extern gid_t multiuser_get_cache_gid(userid_t user_id, appid_t app_id);
+extern gid_t multiuser_get_shared_gid(userid_t user_id, appid_t app_id);
+
+/* TODO: switch callers over to multiuser_get_shared_gid() */
+extern gid_t multiuser_get_shared_app_gid(uid_t uid);
#ifdef __cplusplus
}