1 files changed, 72 insertions, 0 deletions
diff --git a/src/buildtool/file_system/git_repo.hpp b/src/buildtool/file_system/git_repo.hpp
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+++ b/src/buildtool/file_system/git_repo.hpp
@@ -0,0 +1,72 @@
+// Copyright 2022 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_FILE_SYSTEM_GIT_REPO_HPP
+#define INCLUDED_SRC_BUILDTOOL_FILE_SYSTEM_GIT_REPO_HPP
+
+#include "src/buildtool/file_system/git_cas.hpp"
+#include "src/buildtool/multithreading/async_map_consumer.hpp"
+
+extern "C" {
+using git_repository = struct git_repository;
+}
+
+/// \brief Git repository logic.
+/// Models both a real repository, owning the underlying ODB
+/// (non-thread-safe), as well as a "fake" repository, which only wraps an
+/// existing ODB, allowing thread-safe operations.
+class GitRepo {
+  public:
+    GitRepo() = delete;  // no default ctor
+
+    // allow only move, no copy
+    GitRepo(GitRepo const&) = delete;
+    GitRepo(GitRepo&&) noexcept;
+    auto operator=(GitRepo const&) = delete;
+    auto operator=(GitRepo&& other) noexcept -> GitRepo&;
+
+    /// \brief Factory to wrap existing open CAS in a "fake" repository.
+    [[nodiscard]] static auto Open(GitCASPtr git_cas) noexcept
+        -> std::optional<GitRepo>;
+
+    /// \brief Factory to open existing real repository at given location.
+    [[nodiscard]] static auto Open(
+        std::filesystem::path const& repo_path) noexcept
+        -> std::optional<GitRepo>;
+
+    /// \brief Factory to initialize and open new real repository at location.
+    /// Returns nullopt if repository init fails even after repeated tries.
+    [[nodiscard]] static auto InitAndOpen(
+        std::filesystem::path const& repo_path,
+        bool is_bare) noexcept -> std::optional<GitRepo>;
+
+    [[nodiscard]] auto GetGitCAS() const noexcept -> GitCASPtr;
+
+    [[nodiscard]] auto IsRepoFake() const noexcept -> bool;
+
+    ~GitRepo() noexcept;
+
+  private:
+    GitCASPtr git_cas_{nullptr};
+    git_repository* repo_{nullptr};
+    // default to real repo, as that is non-thread-safe
+    bool is_repo_fake_{false};
+
+    /// \brief Open "fake" repository wrapper for existing CAS.
+    explicit GitRepo(GitCASPtr git_cas) noexcept;
+    /// \brief Open real repository at given location.
+    explicit GitRepo(std::filesystem::path const& repo_path) noexcept;
+};
+
+#endif  // INCLUDED_SRC_BUILDTOOL_FILE_SYSTEM_GIT_REPO_HPP
+\ No newline at end of file