installd create_data_user_ce_path uses dir instead of symlink

Select whichever is real dir instead of symbolic link from either
/data/data or /data/user/0. This is to minimize path walking overhead
in kernel.

Test: Manual test
Change-Id: Ie06640624746ff40a2b5b47ead50a7f10eb2db3e
Signed-off-by: cjbao <cathy.bao@intel.com>

1 files changed, 8 insertions, 7 deletions

diff --git a/cmds/installd/utils.cpp b/cmds/installd/utils.cpp
index bdd62e6554..6747f0ad51 100644
--- a/cmds/installd/utils.cpp
+++ b/cmds/installd/utils.cpp
@@ -170,18 +170,19 @@ std::string create_data_app_path(const char* volume_uuid) {
 
 /**
  * Create the path name for user data for a certain userid.
+ * Keep same implementation as vold to minimize path walking overhead
  */
 std::string create_data_user_ce_path(const char* volume_uuid, userid_t userid) {
     std::string data(create_data_path(volume_uuid));
-    if (volume_uuid == nullptr) {
-        if (userid == 0) {
-            return StringPrintf("%s/data", data.c_str());
-        } else {
-            return StringPrintf("%s/user/%u", data.c_str(), userid);
+    if (volume_uuid == nullptr && userid == 0) {
+        std::string legacy = StringPrintf("%s/data", data.c_str());
+        struct stat sb;
+        if (lstat(legacy.c_str(), &sb) == 0 && S_ISDIR(sb.st_mode)) {
+            /* /data/data is dir, return /data/data for legacy system */
+            return legacy;
         }
-    } else {
-        return StringPrintf("%s/user/%u", data.c_str(), userid);
     }
+    return StringPrintf("%s/user/%u", data.c_str(), userid);
 }
 
 /**