backup garbage collect shared_checksum tmp files

Summary:
previously we only cleaned up .tmp files under "shared/" and "private/" directories in case the previous backup failed. we need to do the same for "shared_checksum/"; otherwise, the subsequent backup will fail if it tries to backup at least one of the same files.
Closes https://github.com/facebook/rocksdb/pull/2062

Differential Revision: D4805599

Pulled By: ajkr

fbshipit-source-id: eaa6088

utilities/backupable/backupable_db.cc

@@ -1458,7 +1458,12 @@ Status BackupEngineImpl::GarbageCollect() {
     // delete obsolete shared files
     std::vector<std::string> shared_children;
     {
-      auto shared_path = GetAbsolutePath(GetSharedFileRel());
+      std::string shared_path;
+      if (options_.share_files_with_checksum) {
+        shared_path = GetAbsolutePath(GetSharedFileWithChecksumRel());
+      } else {
+        shared_path = GetAbsolutePath(GetSharedFileRel());
+      }
       auto s = backup_env_->FileExists(shared_path);
       if (s.ok()) {
         s = backup_env_->GetChildren(shared_path, &shared_children);
@@ -1470,7 +1475,12 @@ Status BackupEngineImpl::GarbageCollect() {
       }
     }
     for (auto& child : shared_children) {
-      std::string rel_fname = GetSharedFileRel(child);
+      std::string rel_fname;
+      if (options_.share_files_with_checksum) {
+        rel_fname = GetSharedFileWithChecksumRel(child);
+      } else {
+        rel_fname = GetSharedFileRel(child);
+      }
       auto child_itr = backuped_file_infos_.find(rel_fname);
       // if it's not refcounted, delete it
       if (child_itr == backuped_file_infos_.end() ||

utilities/backupable/backupable_db_test.cc

@@ -1126,22 +1126,42 @@ TEST_F(BackupableDBTest, ShareTableFilesWithChecksumsTransition) {
 }
 
 TEST_F(BackupableDBTest, DeleteTmpFiles) {
+  for (bool shared_checksum : {false, true}) {
+    if (shared_checksum) {
+      OpenDBAndBackupEngineShareWithChecksum(
+          false /* destroy_old_data */, false /* dummy */,
+          true /* share_table_files */, true /* share_with_checksums */);
+    } else {
       OpenDBAndBackupEngine();
+    }
     CloseDBAndBackupEngine();
-  std::string shared_tmp = backupdir_ + "/shared/00006.sst.tmp";
+    std::string shared_tmp = backupdir_;
+    if (shared_checksum) {
+      shared_tmp += "/shared_checksum";
+    } else {
+      shared_tmp += "/shared";
+    }
+    shared_tmp += "/00006.sst.tmp";
     std::string private_tmp_dir = backupdir_ + "/private/10.tmp";
     std::string private_tmp_file = private_tmp_dir + "/00003.sst";
     file_manager_->WriteToFile(shared_tmp, "tmp");
     file_manager_->CreateDir(private_tmp_dir);
     file_manager_->WriteToFile(private_tmp_file, "tmp");
     ASSERT_OK(file_manager_->FileExists(private_tmp_dir));
+    if (shared_checksum) {
+      OpenDBAndBackupEngineShareWithChecksum(
+          false /* destroy_old_data */, false /* dummy */,
+          true /* share_table_files */, true /* share_with_checksums */);
+    } else {
       OpenDBAndBackupEngine();
+    }
     // Need to call this explicitly to delete tmp files
     (void)backup_engine_->GarbageCollect();
     CloseDBAndBackupEngine();
     ASSERT_EQ(Status::NotFound(), file_manager_->FileExists(shared_tmp));
     ASSERT_EQ(Status::NotFound(), file_manager_->FileExists(private_tmp_file));
     ASSERT_EQ(Status::NotFound(), file_manager_->FileExists(private_tmp_dir));
+  }
 }
 
 TEST_F(BackupableDBTest, KeepLogFiles) {