Compactification: Implement a generic concurrent logic.

1 files changed, 95 insertions, 0 deletions

diff --git a/src/buildtool/storage/compactification_task.hpp b/src/buildtool/storage/compactification_task.hpp
new file mode 100644
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+++ b/src/buildtool/storage/compactification_task.hpp
@@ -0,0 +1,95 @@
+// Copyright 2024 Huawei Cloud Computing Technology Co., Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef INCLUDED_SRC_BUILDTOOL_STORAGE_COMPACTIFICATION_TASK_HPP
+#define INCLUDED_SRC_BUILDTOOL_STORAGE_COMPACTIFICATION_TASK_HPP
+
+#include <filesystem>
+#include <functional>
+#include <string>
+
+#include "fmt/core.h"
+#include "src/buildtool/logging/log_level.hpp"
+#include "src/buildtool/logging/logger.hpp"
+#include "src/buildtool/storage/local_cas.hpp"
+
+/// \brief Set of data that defines a compactification task.
+/// \param cas          CAS to be scanned.
+/// \param large        True if large storages need to be scanned.
+/// \param f_task       A handler for ObjectType::File entries.
+/// \param x_task       A handler for ObjectType::Executable entries.
+/// It is never called during scanning of large storages.
+/// \param t_task       A handler for ObjectType::Tree entries.
+/// \param logger       A callback for logging.
+/// \param filter       A callback that defines which files must be processed.
+struct CompactificationTask final {
+    using Logger = std::function<void(LogLevel, std::string const&)>;
+    using Filter = std::function<bool(std::filesystem::path const&)>;
+    using ObjectTask = std::function<bool(CompactificationTask const&,
+                                          std::filesystem::path const&)>;
+
+    static inline const Logger kLoggerDefault = [](LogLevel level,
+                                                   std::string const& message) {
+        ::Logger::Log(level, "{}", message);
+    };
+    static inline const Filter kFilterDefault =
+        [](std::filesystem::path const& /*unused*/) { return false; };
+    static inline const ObjectTask kObjectTaskDefault =
+        [](CompactificationTask const& /*unused*/,
+           std::filesystem::path const& /*unused*/) {
+            kLoggerDefault(LogLevel::Error, "Default ObjectTask was called");
+            return false;
+        };
+
+    LocalCAS<false> const& cas;
+    bool large = false;
+    Logger logger = kLoggerDefault;
+    Filter filter = kFilterDefault;
+    ObjectTask f_task = kObjectTaskDefault;
+    ObjectTask x_task = kObjectTaskDefault;
+    ObjectTask t_task = kObjectTaskDefault;
+
+    /// \brief Log a formatted error.
+    template <typename... Args>
+    void Log(LogLevel level,
+             std::string const& message,
+             Args&&... args) const noexcept;
+};
+
+/// \brief Execute the comapctification task using multiple threads.
+/// Execution of the CompactificationTask-defined logic begins only after the
+/// entire storage has been scanned, otherwise the storage may be invalidated.
+/// Example: casf is scanned while another thread puts new split chunks there.
+/// \return         True if execution was successful.
+[[nodiscard]] auto CompactifyConcurrently(
+    CompactificationTask const& task) noexcept -> bool;
+
+template <typename... Args>
+void CompactificationTask::Log(LogLevel level,
+                               std::string const& message,
+                               Args&&... args) const noexcept {
+    if (not logger) {
+        ::Logger::Log(LogLevel::Error, "Logger is missing.");
+        return;
+    }
+    auto msg = fmt::vformat(message, fmt::make_format_args(args...));
+    try {
+        std::invoke(logger, level, msg);
+    } catch (...) {
+        ::Logger::Log(LogLevel::Error, "Failed to invoke a logger");
+        ::Logger::Log(level, "{}", msg);
+    }
+}
+
+#endif  // INCLUDED_SRC_BUILDTOOL_STORAGE_COMPACTIFICATION_TASK_HPP