Finish BackupEngine migration to IOStatus (#8940)

Summary:
Updates a few remaining functions that should have been updated
from Status -> IOStatus, and adds to HISTORY for the overall change
including https://github.com/facebook/rocksdb/issues/8820.

This change is for inclusion in version 6.25.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8940

Test Plan: CI

Reviewed By: zhichao-cao

Differential Revision: D31085029

Pulled By: pdillinger

fbshipit-source-id: 91557c6a39ef1d90357d4f4dcd79af0645d87c7b

HISTORY.md

@@ -40,6 +40,7 @@
 * Made Statistics extend the Customizable class and added a CreateFromString method.  Implementations of Statistics need to be registered with the ObjectRegistry and to implement a Name() method in order to be created via this method.
 * Extended `FlushJobInfo` and `CompactionJobInfo` in listener.h to provide information about the blob files generated by a flush/compaction and garbage collected during compaction in Integrated BlobDB. Added struct members `blob_file_addition_infos` and `blob_file_garbage_infos` that contain this information.
 * Extended parameter `output_file_names` of `CompactFiles` API to also include paths of the blob files generated by the compaction in Integrated BlobDB.
+* Most `BackupEngine` functions now return `IOStatus` instead of `Status`. Most existing code should be compatible with this change but some calls might need to be updated.
 
 ## 6.24.0 (2021-08-20)
 ### Bug Fixes

include/rocksdb/utilities/backup_engine.h

@@ -392,10 +392,10 @@ class BackupEngineReadOnlyBase {
   virtual Status GetBackupInfo(BackupID backup_id, BackupInfo* backup_info,
                                bool include_file_details = false) const = 0;
 
-  // Returns info about backups in backup_info
+  // Returns info about non-corrupt backups in backup_infos.
   // Setting include_file_details=true provides information about each
   // backed-up file in BackupInfo::file_details and more.
-  virtual void GetBackupInfo(std::vector<BackupInfo>* backup_info,
+  virtual void GetBackupInfo(std::vector<BackupInfo>* backup_infos,
                              bool include_file_details = false) const = 0;
 
   // Returns info about corrupt backups in corrupt_backups.
@@ -475,13 +475,13 @@ class BackupEngineAppendOnlyBase {
   // Captures the state of the database by creating a new (latest) backup.
   // On success (OK status), the BackupID of the new backup is saved to
   // *new_backup_id when not nullptr.
-  virtual Status CreateNewBackup(const CreateBackupOptions& options, DB* db,
+  virtual IOStatus CreateNewBackup(const CreateBackupOptions& options, DB* db,
                                    BackupID* new_backup_id = nullptr) {
     return CreateNewBackupWithMetadata(options, db, "", new_backup_id);
   }
 
   // keep here for backward compatibility.
-  virtual Status CreateNewBackup(
+  virtual IOStatus CreateNewBackup(
       DB* db, bool flush_before_backup = false,
       std::function<void()> progress_callback = []() {}) {
     CreateBackupOptions options;
@@ -575,11 +575,11 @@ class BackupEngine : public BackupEngineReadOnlyBase,
 
   // BackupEngineOptions have to be the same as the ones used in previous
   // BackupEngines for the same backup directory.
-  static Status Open(const BackupEngineOptions& options, Env* db_env,
+  static IOStatus Open(const BackupEngineOptions& options, Env* db_env,
                        BackupEngine** backup_engine_ptr);
 
   // keep for backward compatibility.
-  static Status Open(Env* db_env, const BackupEngineOptions& options,
+  static IOStatus Open(Env* db_env, const BackupEngineOptions& options,
                        BackupEngine** backup_engine_ptr) {
     return BackupEngine::Open(options, db_env, backup_engine_ptr);
   }
@@ -601,10 +601,10 @@ class BackupEngineReadOnly : public BackupEngineReadOnlyBase {
  public:
   virtual ~BackupEngineReadOnly() {}
 
-  static Status Open(const BackupEngineOptions& options, Env* db_env,
+  static IOStatus Open(const BackupEngineOptions& options, Env* db_env,
                        BackupEngineReadOnly** backup_engine_ptr);
   // keep for backward compatibility.
-  static Status Open(Env* db_env, const BackupEngineOptions& options,
+  static IOStatus Open(Env* db_env, const BackupEngineOptions& options,
                        BackupEngineReadOnly** backup_engine_ptr) {
     return BackupEngineReadOnly::Open(options, db_env, backup_engine_ptr);
   }

utilities/backupable/backupable_db.cc

@@ -895,7 +895,7 @@ class BackupEngineImplThreadSafe : public BackupEngine,
   }
 
   // Not public API but needed
-  Status Initialize() {
+  IOStatus Initialize() {
     // No locking needed
     return impl_.Initialize();
   }
@@ -912,7 +912,7 @@ class BackupEngineImplThreadSafe : public BackupEngine,
   BackupEngineImpl impl_;
 };
 
-Status BackupEngine::Open(const BackupEngineOptions& options, Env* env,
+IOStatus BackupEngine::Open(const BackupEngineOptions& options, Env* env,
                             BackupEngine** backup_engine_ptr) {
   std::unique_ptr<BackupEngineImplThreadSafe> backup_engine(
       new BackupEngineImplThreadSafe(options, env));
@@ -922,7 +922,7 @@ Status BackupEngine::Open(const BackupEngineOptions& options, Env* env,
     return s;
   }
   *backup_engine_ptr = backup_engine.release();
-  return Status::OK();
+  return IOStatus::OK();
 }
 
 BackupEngineImpl::BackupEngineImpl(const BackupEngineOptions& options,
@@ -2986,10 +2986,11 @@ IOStatus BackupEngineImpl::BackupMeta::StoreToFile(
   return io_s;
 }
 
-Status BackupEngineReadOnly::Open(const BackupEngineOptions& options, Env* env,
+IOStatus BackupEngineReadOnly::Open(const BackupEngineOptions& options,
+                                    Env* env,
                                     BackupEngineReadOnly** backup_engine_ptr) {
   if (options.destroy_old_data) {
-    return Status::InvalidArgument(
+    return IOStatus::InvalidArgument(
         "Can't destroy old data with ReadOnly BackupEngine");
   }
   std::unique_ptr<BackupEngineImplThreadSafe> backup_engine(
@@ -3000,7 +3001,7 @@ Status BackupEngineReadOnly::Open(const BackupEngineOptions& options, Env* env,
     return s;
   }
   *backup_engine_ptr = backup_engine.release();
-  return Status::OK();
+  return IOStatus::OK();
 }
 
 void TEST_EnableWriteFutureSchemaVersion2(