Allow ProcessUpdateState to be paused.
Change callback type of ProcessUpdateState to bool() so that, when callback
returns false, immediately returns Merging.
Test: libsnapshot_test
Bug: 147696014
Change-Id: I9dcb8e1658b95216c0f1991e2e4c1ea2e7e7b2e5
Merged-In: I9dcb8e1658b95216c0f1991e2e4c1ea2e7e7b2e5
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
index c8cbb1e..72f1d91 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
@@ -148,7 +148,11 @@
// /data is mounted.
//
// If a merge is in progress, this function will block until the merge is
- // completed. If a merge or update was cancelled, this will clean up any
+ // completed.
+ // - Callback is called periodically during the merge. If callback()
+ // returns false during the merge, ProcessUpdateState() will pause
+ // and returns Merging.
+ // If a merge or update was cancelled, this will clean up any
// update artifacts and return.
//
// Note that after calling this, GetUpdateState() may still return that a
@@ -168,7 +172,7 @@
//
// The optional callback allows the caller to periodically check the
// progress with GetUpdateState().
- UpdateState ProcessUpdateState(const std::function<void()>& callback = {},
+ UpdateState ProcessUpdateState(const std::function<bool()>& callback = {},
const std::function<bool()>& before_cancel = {});
// Initiate the merge if necessary, then wait for the merge to finish.
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index b3aa9f0..7a4f3dc 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -794,7 +794,7 @@
// Note that when a merge fails, we will *always* try again to complete the
// merge each time the device boots. There is no harm in doing so, and if
// the problem was transient, we might manage to get a new outcome.
-UpdateState SnapshotManager::ProcessUpdateState(const std::function<void()>& callback,
+UpdateState SnapshotManager::ProcessUpdateState(const std::function<bool()>& callback,
const std::function<bool()>& before_cancel) {
while (true) {
UpdateState state = CheckMergeState(before_cancel);
@@ -807,8 +807,8 @@
return state;
}
- if (callback) {
- callback();
+ if (callback && !callback()) {
+ return state;
}
// This wait is not super time sensitive, so we have a relatively
@@ -2410,13 +2410,14 @@
SnapshotMergeStats merge_stats(*this);
unsigned int last_progress = 0;
- auto callback = [&]() -> void {
+ auto callback = [&]() -> bool {
double progress;
GetUpdateState(&progress);
if (last_progress < static_cast<unsigned int>(progress)) {
last_progress = progress;
LOG(INFO) << "Waiting for merge to complete: " << last_progress << "%.";
}
+ return true; // continue
};
LOG(INFO) << "Waiting for any previous merge request to complete. "
@@ -2512,7 +2513,10 @@
return false;
}
- UpdateState state = ProcessUpdateState(callback);
+ UpdateState state = ProcessUpdateState([&]() -> bool {
+ callback();
+ return true;
+ });
LOG(INFO) << "Update state in recovery: " << state;
switch (state) {
case UpdateState::MergeFailed: