Make non-volatile directory platform-specific.
update_engine daemon needs to persist files (such as the progress of
the update) in a non-volatile storage and also used to store a
marker file on a volatile storage to detect when update_engine is
restarted, likelly due to a crash.
This patch moves the non-volatile directory configuration to the
Hardware interface, making it platform-specific. It also replaces the
system rebooted detection using the boot_id provided by the kernel
instead of storing a file under /tmp. This implementation works both
on Chrome OS and Android.
Bug: 24074252
Test: FEATURES=test emerge-link update_engine; `mma`; deployed and tested manually on brillo.
Change-Id: I921d767982adebfd04eb12e08d8a157d9102d1e3
diff --git a/utils.h b/utils.h
index 803a0d6..6668c39 100644
--- a/utils.h
+++ b/utils.h
@@ -416,6 +416,11 @@
chromeos::Blob* out_data, ssize_t out_data_size,
size_t block_size);
+// Read the current boot identifier and store it in |boot_id|. This identifier
+// is constants during the same boot of the kernel and is regenerated after
+// reboot. Returns whether it succeeded getting the boot_id.
+bool GetBootId(std::string* boot_id);
+
} // namespace utils