Merge "libsnapshot: Add a merge failure code to SnapshotMergeReport."

fs_mgr/libsnapshot/android/snapshot/snapshot.proto

@@ -186,7 +186,7 @@ message SnapshotUpdateStatus {
     MergeFailureCode merge_failure_code = 7;
 }
 
-// Next: 9
+// Next: 10
 message SnapshotMergeReport {
     // Status of the update after the merge attempts.
     UpdateState state = 1;
@@ -212,4 +212,7 @@ message SnapshotMergeReport {
 
     // Time from sys.boot_completed to merge start, in milliseconds.
     uint32 boot_complete_to_merge_start_time_ms = 8;
+
+    // Merge failure code, filled if state == MergeFailed.
+    MergeFailureCode merge_failure_code = 9;
 }

fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot.h

@@ -27,6 +27,7 @@ class MockSnapshotManager : public ISnapshotManager {
     MOCK_METHOD(bool, CancelUpdate, (), (override));
     MOCK_METHOD(bool, FinishedSnapshotWrites, (bool wipe), (override));
     MOCK_METHOD(void, UpdateCowStats, (ISnapshotMergeStats * stats), (override));
+    MOCK_METHOD(MergeFailureCode, ReadMergeFailureCode, (), (override));
     MOCK_METHOD(bool, InitiateMerge, (), (override));
 
     MOCK_METHOD(UpdateState, ProcessUpdateState,

fs_mgr/libsnapshot/include/libsnapshot/mock_snapshot_merge_stats.h

@@ -34,11 +34,13 @@ class MockSnapshotMergeStats final : public ISnapshotMergeStats {
     MOCK_METHOD(void, set_estimated_cow_size_bytes, (uint64_t), (override));
     MOCK_METHOD(void, set_boot_complete_time_ms, (uint32_t), (override));
     MOCK_METHOD(void, set_boot_complete_to_merge_start_time_ms, (uint32_t), (override));
+    MOCK_METHOD(void, set_merge_failure_code, (MergeFailureCode), (override));
     MOCK_METHOD(uint64_t, cow_file_size, (), (override));
     MOCK_METHOD(uint64_t, total_cow_size_bytes, (), (override));
     MOCK_METHOD(uint64_t, estimated_cow_size_bytes, (), (override));
     MOCK_METHOD(uint32_t, boot_complete_time_ms, (), (override));
     MOCK_METHOD(uint32_t, boot_complete_to_merge_start_time_ms, (), (override));
+    MOCK_METHOD(MergeFailureCode, merge_failure_code, (), (override));
     MOCK_METHOD(std::unique_ptr<Result>, Finish, (), (override));
 
     using ISnapshotMergeStats::Result;

fs_mgr/libsnapshot/include/libsnapshot/snapshot.h

@@ -167,6 +167,10 @@ class ISnapshotManager {
     virtual UpdateState ProcessUpdateState(const std::function<bool()>& callback = {},
                                            const std::function<bool()>& before_cancel = {}) = 0;
 
+    // If ProcessUpdateState() returned MergeFailed, this returns the appropriate
+    // code. Otherwise, MergeFailureCode::Ok is returned.
+    virtual MergeFailureCode ReadMergeFailureCode() = 0;
+
     // Find the status of the current update, if any.
     //
     // |progress| depends on the returned status:
@@ -332,6 +336,7 @@ class SnapshotManager final : public ISnapshotManager {
     bool CancelUpdate() override;
     bool FinishedSnapshotWrites(bool wipe) override;
     void UpdateCowStats(ISnapshotMergeStats* stats) override;
+    MergeFailureCode ReadMergeFailureCode() override;
     bool InitiateMerge() override;
     UpdateState ProcessUpdateState(const std::function<bool()>& callback = {},
                                    const std::function<bool()>& before_cancel = {}) override;

fs_mgr/libsnapshot/include/libsnapshot/snapshot_stats.h

@@ -34,11 +34,13 @@ class ISnapshotMergeStats {
     virtual void set_estimated_cow_size_bytes(uint64_t bytes) = 0;
     virtual void set_boot_complete_time_ms(uint32_t ms) = 0;
     virtual void set_boot_complete_to_merge_start_time_ms(uint32_t ms) = 0;
+    virtual void set_merge_failure_code(MergeFailureCode code) = 0;
     virtual uint64_t cow_file_size() = 0;
     virtual uint64_t total_cow_size_bytes() = 0;
     virtual uint64_t estimated_cow_size_bytes() = 0;
     virtual uint32_t boot_complete_time_ms() = 0;
     virtual uint32_t boot_complete_to_merge_start_time_ms() = 0;
+    virtual MergeFailureCode merge_failure_code() = 0;
 
     // Called when merge ends. Properly clean up permanent storage.
     class Result {
@@ -70,6 +72,8 @@ class SnapshotMergeStats : public ISnapshotMergeStats {
     uint32_t boot_complete_time_ms() override;
     void set_boot_complete_to_merge_start_time_ms(uint32_t ms) override;
     uint32_t boot_complete_to_merge_start_time_ms() override;
+    void set_merge_failure_code(MergeFailureCode code) override;
+    MergeFailureCode merge_failure_code() override;
     std::unique_ptr<Result> Finish() override;
 
   private:

fs_mgr/libsnapshot/include/libsnapshot/snapshot_stub.h

@@ -29,6 +29,7 @@ class SnapshotManagerStub : public ISnapshotManager {
     bool CancelUpdate() override;
     bool FinishedSnapshotWrites(bool wipe) override;
     void UpdateCowStats(ISnapshotMergeStats* stats) override;
+    MergeFailureCode ReadMergeFailureCode() override;
     bool InitiateMerge() override;
     UpdateState ProcessUpdateState(const std::function<bool()>& callback = {},
                                    const std::function<bool()>& before_cancel = {}) override;

fs_mgr/libsnapshot/snapshot.cpp

@@ -3690,5 +3690,16 @@ bool SnapshotManager::DeleteDeviceIfExists(const std::string& name,
     return false;
 }
 
+MergeFailureCode SnapshotManager::ReadMergeFailureCode() {
+    auto lock = LockExclusive();
+    if (!lock) return MergeFailureCode::AcquireLock;
+
+    SnapshotUpdateStatus status = ReadSnapshotUpdateStatus(lock.get());
+    if (status.state() != UpdateState::MergeFailed) {
+        return MergeFailureCode::Ok;
+    }
+    return status.merge_failure_code();
+}
+
 }  // namespace snapshot
 }  // namespace android

fs_mgr/libsnapshot/snapshot_stats.cpp

@@ -130,6 +130,14 @@ uint32_t SnapshotMergeStats::boot_complete_to_merge_start_time_ms() {
     return report_.boot_complete_to_merge_start_time_ms();
 }
 
+void SnapshotMergeStats::set_merge_failure_code(MergeFailureCode code) {
+    report_.set_merge_failure_code(code);
+}
+
+MergeFailureCode SnapshotMergeStats::merge_failure_code() {
+    return report_.merge_failure_code();
+}
+
 class SnapshotMergeStatsResultImpl : public SnapshotMergeStats::Result {
   public:
     SnapshotMergeStatsResultImpl(const SnapshotMergeReport& report,

fs_mgr/libsnapshot/snapshot_stub.cpp

@@ -135,6 +135,8 @@ class SnapshotMergeStatsStub : public ISnapshotMergeStats {
     uint32_t boot_complete_time_ms() override { return 0; }
     void set_boot_complete_to_merge_start_time_ms(uint32_t) override {}
     uint32_t boot_complete_to_merge_start_time_ms() override { return 0; }
+    void set_merge_failure_code(MergeFailureCode) override {}
+    MergeFailureCode merge_failure_code() { return MergeFailureCode::Ok; }
 };
 
 ISnapshotMergeStats* SnapshotManagerStub::GetSnapshotMergeStatsInstance() {
@@ -163,4 +165,9 @@ void SnapshotManagerStub::UpdateCowStats(ISnapshotMergeStats*) {
     LOG(ERROR) << __FUNCTION__ << " should never be called.";
 }
 
+auto SnapshotManagerStub::ReadMergeFailureCode() -> MergeFailureCode {
+    LOG(ERROR) << __FUNCTION__ << " should never be called.";
+    return MergeFailureCode::Ok;
+}
+
 }  // namespace android::snapshot