snapshot.hpp

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#ifndef GUARD_SQLITE_SNAPSHOT_HPP_INCLUDED
#define GUARD_SQLITE_SNAPSHOT_HPP_INCLUDED
 
#include <string>
#include <string_view>
 
struct sqlite3_snapshot;

namespace sqlite {
inline namespace v2 {
    struct connection;
 
    enum class wal_mode {
        rollback, 
        truncate,
        persist,
        memory,
        wal,
        wal2
    };

    struct snapshot {
        snapshot() = default;
        ~snapshot();
 
        snapshot(snapshot const &)            = delete;
        snapshot &operator=(snapshot const &) = delete;
 
        snapshot(snapshot &&other) noexcept;
        snapshot &operator=(snapshot &&other) noexcept;
 
        bool valid() const noexcept {
            return handle_ != nullptr;
        }
        explicit operator bool() const noexcept {
            return valid();
        }

        void reset() noexcept;

        static snapshot take(connection &con, std::string_view schema = "main");

        void open(connection &con, std::string_view schema = "main") const;
 
        sqlite3_snapshot *native_handle() const noexcept {
            return handle_;
        }
 
    private:
        explicit snapshot(sqlite3_snapshot *handle);
        sqlite3_snapshot *handle_ = nullptr;
    };

    wal_mode set_wal_mode(connection &con, wal_mode mode);

    wal_mode enable_wal(connection &con, bool prefer_wal2 = false);

    wal_mode get_wal_mode(connection &con);

    std::string_view to_string(wal_mode mode);

    bool snapshots_supported() noexcept;
} // namespace v2
} // namespace sqlite
 
#endif // GUARD_SQLITE_SNAPSHOT_HPP_INCLUDED