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Diffstat (limited to 'include/boost/sqlite/static_resultset.hpp')
| -rw-r--r-- | include/boost/sqlite/static_resultset.hpp | 497 |
1 files changed, 0 insertions, 497 deletions
diff --git a/include/boost/sqlite/static_resultset.hpp b/include/boost/sqlite/static_resultset.hpp deleted file mode 100644 index fd6c359..0000000 --- a/include/boost/sqlite/static_resultset.hpp +++ /dev/null @@ -1,497 +0,0 @@ -// -// Copyright (c) 2024 Klemens Morgenstern (klemens.morgenstern@gmx.net) -// -// Distributed under the Boost Software License, Version 1.0. (See accompanying -// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -// - -#ifndef BOOST_SQLITE_STATIC_RESULTSET_HPP -#define BOOST_SQLITE_STATIC_RESULTSET_HPP - -#include <boost/sqlite/detail/config.hpp> -#include <boost/sqlite/resultset.hpp> -#include <boost/sqlite/connection.hpp> - -#include <boost/describe/members.hpp> - -#include <array> -#include <cstdint> - -#if __cplusplus >= 202002L -#include <boost/pfr/core.hpp> -#include <boost/pfr/core_name.hpp> -#include <boost/pfr/traits.hpp> -#endif - - -namespace boost { template<typename> class optional;} - -#if __cplusplus >= 201702L -#include <optional> -#endif - -BOOST_SQLITE_BEGIN_NAMESPACE - -namespace detail -{ - -inline void convert_field(sqlite_int64 & target, const field & f) {target = f.get_int();} - -template<typename = std::enable_if_t<!std::is_same<std::int64_t, sqlite_int64>::value>> -inline void convert_field(std::int64_t & target, const field & f) -{ - target = static_cast<std::int64_t>(f.get_int()); -} - -inline void convert_field(double & target, const field & f) {target = f.get_double();} - - -template<typename Traits = std::char_traits<char>, typename Allocator = std::allocator<char>> -inline void convert_field(std::basic_string<char, Traits, Allocator> & target, const field & f) -{ - auto t = f.get_text(); - target.assign(t.begin(), t.end()); -} - -inline void convert_field(string_view & target, const field & f) {target = f.get_text();} -inline void convert_field(blob & target, const field & f) {target = blob(f.get_blob());} -inline void convert_field(blob_view & target, const field & f) {target = f.get_blob();} - -#if __cplusplus >= 201702L -template<typename T> -inline void convert_field(std::optional<T> & target, const field & f) -{ - if (f.is_null()) - target.reset(); - else - convert_field(target.emplace(), f); -} -#endif - -template<typename T> -inline void convert_field(boost::optional<T> & target, const field & f) -{ - if (f.is_null()) - target.reset(); - else - return convert_field(target.emplace_back(), f); -} - -template<typename T> -inline constexpr bool field_type_is_nullable(const T& ) {return false;} -#if __cplusplus >= 201702L -template<typename T> -inline bool field_type_is_nullable(const std::optional<T> &) { return true; } -#endif -template<typename T> -inline bool field_type_is_nullable(const boost::optional<T> &) { return true; } - -inline value_type required_field_type(const sqlite3_int64 &) {return value_type::integer;} - -template<typename = std::enable_if_t<!std::is_same<std::int64_t, sqlite_int64>::value>> -inline value_type required_field_type(const std::int64_t &) {return value_type::integer;} - -template<typename Allocator, typename Traits> -inline value_type required_field_type(const std::basic_string<char, Allocator, Traits> & ) -{ - return value_type::text; -} - -inline value_type required_field_type(const string_view &) {return value_type::text;} -inline value_type required_field_type(const blob &) {return value_type::blob;} -inline value_type required_field_type(const blob_view &) {return value_type::blob;} - - -template<typename ... Args> -void check_columns(const std::tuple<Args...> *, const resultset & r, - system::error_code &ec, error_info & ei) -{ - if (r.column_count() != sizeof...(Args)) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_MISMATCH); - ei.format("Tuple size doesn't match column count [%ld != %ld]", sizeof...(Args), r.column_count()); - } -} - -template<bool Strict, typename ... Args> -void convert_row(std::tuple<Args...> & res, const row & r, system::error_code ec, error_info & ei) -{ - std::size_t idx = 0u; - - mp11::tuple_for_each( - res, - [&](auto & v) - { - const auto i = idx++; - const auto & f = r[i]; - BOOST_IF_CONSTEXPR (Strict) - { - if (!ec) // only check if we don't have an error yet. - { - if (f.is_null() && !field_type_is_nullable(v)) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_CONSTRAINT_NOTNULL); - ei.format("unexpected null in column %d", i); - } - else if (f.type() != required_field_type(v)) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_CONSTRAINT_DATATYPE); - ei.format("unexpected type [%s] in column %d, expected [%s]", - value_type_name(f.type()), i, value_type_name(required_field_type(v))); - } - } - } - else - boost::ignore_unused(ec, ei); - - detail::convert_field(v, f); - }); -} - -#if defined(BOOST_DESCRIBE_CXX14) - -template<typename T, typename = typename std::enable_if<describe::has_describe_members<T>::value>::type> -void check_columns(const T *, const resultset & r, - system::error_code &ec, error_info & ei) -{ - using mems = boost::describe::describe_members<T, describe::mod_public>; - constexpr std::size_t sz = mp11::mp_size<mems>(); - if (r.column_count() != sz) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_MISMATCH); - ei.format("Describe size doesn't match column count [%ld != %ld]", sz, r.column_count()); - } - - // columns can be duplicated! - std::array<bool, sz> found; - std::fill(found.begin(), found.end(), false); - - for (std::size_t i = 0ul; i < r.column_count(); i++) - { - bool cfound = false; - boost::mp11::mp_for_each<mp11::mp_iota_c<sz>>( - [&](auto sz) - { - auto d = mp11::mp_at_c<mems, sz>(); - if (d.name == r.column_name(i)) - { - found[sz] = true; - cfound = true; - } - }); - - if (!cfound) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_MISMATCH); - ei.format("Column '%s' not found in described struct.", r.column_name(i).c_str()); - break; - } - } - - if (ec) - return; - - - auto itr = std::find(found.begin(), found.end(), false); - if (itr != found.end()) - { - mp11::mp_with_index<sz>( - std::distance(found.begin(), itr), - [&](auto sz) - { - auto d = mp11::mp_at_c<mems, sz>(); - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_MISMATCH); - ei.format("Described field '%s' not found in resultset struct.", d.name); - }); - } -} - -template<bool Strict, typename T, - typename = typename std::enable_if<describe::has_describe_members<T>::value>::type> -void convert_row(T & res, const row & r, system::error_code ec, error_info & ei) -{ - for (auto && f: r) - { - boost::mp11::mp_for_each<boost::describe::describe_members<T, describe::mod_public> >( - [&](auto D) - { - if (D.name == f.column_name()) - { - auto & r = res.*D.pointer; - BOOST_IF_CONSTEXPR(Strict) - { - if (!ec) - { - if (f.is_null() && !field_type_is_nullable(r)) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_CONSTRAINT_NOTNULL); - ei.format("unexpected null in column %s", D.name); - } - else if (f.type() != required_field_type(r)) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_CONSTRAINT_DATATYPE); - ei.format("unexpected type [%s] in column %s, expected [%s]", - value_type_name(f.type()), D.name, value_type_name(required_field_type(r))); - } - } - } - - detail::convert_field(r, f); - } - }); - } -} - -#endif - -#if __cplusplus >= 202002L - -template<typename T> - requires (std::is_aggregate_v<T> && !describe::has_describe_members<T>::value) -void check_columns(const T *, const resultset & r, - system::error_code &ec, error_info & ei) -{ - constexpr std::size_t sz = pfr::tuple_size_v<T>; - if (r.column_count() != sz) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_MISMATCH); - ei.format("Describe size doesn't match column count [%ld != %ld]", sz, r.column_count()); - } - - // columns can be duplicated! - std::array<bool, sz> found; - std::fill(found.begin(), found.end(), false); - - for (std::size_t i = 0ul; i < r.column_count(); i++) - { - bool cfound = false; - boost::mp11::mp_for_each<mp11::mp_iota_c<sz>>( - [&](auto sz) - { - if (pfr::get_name<sz, T>() == r.column_name(i)) - { - found[sz] = true; - cfound = true; - } - }); - - if (!cfound) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_MISMATCH); - ei.format("Column %s not found in struct.", r.column_name(i).c_str()); - break; - } - } - - if (ec) - return; - - - auto itr = std::find(found.begin(), found.end(), false); - if (itr != found.end()) - { - mp11::mp_with_index<sz>( - std::distance(found.begin(), itr), - [&](auto sz) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_MISMATCH); - auto nm = pfr::get_name<sz, T>(); - ei.format("PFR field %.*s not found in resultset struct.", static_cast<int>(nm.size()), nm.data()); - }); - } -} - -template<bool Strict, typename T> - requires (std::is_aggregate_v<T> && !describe::has_describe_members<T>::value) -void convert_row(T & res, const row & r, system::error_code ec, error_info & ei) -{ - for (auto && f: r) - { - boost::mp11::mp_for_each<mp11::mp_iota_c<pfr::tuple_size_v<T>>>( - [&](auto D) - { - if (pfr::get_name<D, T>() == f.column_name().c_str()) - { - auto & r = pfr::get<D()>(res); - BOOST_IF_CONSTEXPR(Strict) - { - if (!ec) - { - if (f.is_null() && !field_type_is_nullable(r)) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_CONSTRAINT_NOTNULL); - ei.format("unexpected null in column %s", D.name); - } - else if (f.type() != required_field_type(r)) - { - BOOST_SQLITE_ASSIGN_EC(ec, SQLITE_CONSTRAINT_DATATYPE); - ei.format("unexpected type [%s] in column %s, expected [%s]", - value_type_name(f.type()), D.name, value_type_name(required_field_type(r))); - } - } - } - detail::convert_field(r, f); - } - }); - } -} - -#endif - -} - -/** - @brief A typed resultset using a tuple or a described struct. - @ingroup reference - @tparam T The static type of the query. - @tparam Strict Disables implicit conversions. - - If is a forward-range with output iterators. - - @par Example - - @code{.cpp} - - extern sqlite::connection conn; - struct user { std::string first_name; std::string last_name; }; - BOOST_DESCRIBE_STRUCT(user, (), (first_name, last_name)); - - sqlite::resultset rs = conn.query("select first_name, last_name from users;"); - - do - { - user usr = r.current(); - handle_row(u); - } - while (rs.read_next()) // read it line by line - - @endcode - -*/ -template<typename T, bool Strict > -struct static_resultset -{ - /// Returns the current row. - T current() const & - { - system::error_code ec; - error_info ei; - auto tmp = current(ec, ei); - if (ec) - throw_exception(system::system_error(ec, ei.message())); - return tmp; - } - - /// Returns the current row. - T current(system::error_code & ec, error_info & ei) const & - { - T res; - detail::convert_row<Strict>(res, result_.current(), ec, ei); - return res; - } - - /// Checks if the last row has been reached. - bool done() const {return result_.done();} - - ///@{ - /// Read the next row. Returns false if there's nothing more to read. - BOOST_SQLITE_DECL bool read_next(system::error_code & ec, error_info & ei) { return result_.read_next(ec, ei); } - BOOST_SQLITE_DECL bool read_next() { return result_.read_next(); } - ///@} - - /// - std::size_t column_count() const { return result_.column_count(); } - /// Returns the name of the column idx. - core::string_view column_name(std::size_t idx) const { return result_.column_name(idx); } - - /// Returns the name of the source table for column idx. - core::string_view table_name(std::size_t idx) const { return result_.table_name(idx);} - /// Returns the origin name of the column for column idx. - core::string_view column_origin_name(std::size_t idx) const { return result_.column_origin_name(idx);} - - static_resultset() = default; - static_resultset(resultset && result) : result_(std::move(result)) { } - - - static_resultset(static_resultset<T, false> && rhs) : result_(std::move(rhs.result_)) {} - - /// The input iterator can be used to read every row in a for-loop - struct iterator - { - using value_type = T; - using difference_type = int; - using reference = T&; - using iterator_category = std::forward_iterator_tag; - - iterator() - { - - } - explicit iterator(resultset::iterator itr) : itr_(itr) - { - system::error_code ec; - error_info ei; - if (itr->size() > 0ul) - detail::convert_row<Strict>(value_, *itr, ec, ei); - if (ec) - throw_exception(system::system_error(ec, ei.message())); - } - - bool operator!=(iterator rhs) const - { - return itr_ != rhs.itr_; - } - - value_type &operator*() { return value_; } - value_type *operator->() { return &value_; } - - iterator& operator++() - { - ++itr_; - - system::error_code ec; - error_info ei; - if (itr_->size() > 0ul) - detail::convert_row<Strict>(value_, *itr_, ec, ei); - if (ec) - throw_exception(system::system_error(ec, ei.message())); - - return *this; - } - iterator operator++(int) - { - auto l = *this; - ++(*this); - return l; - } - private: - resultset::iterator itr_; - value_type value_; - }; - - /// Return an input iterator to the currently unread row - iterator begin() { return iterator(result_.begin());} - /// Sentinel iterator. - iterator end() { return iterator(result_.end()); } - - - - static_resultset<T, true> strict() && - { - return {std::move(result_)}; - } - private: - - friend struct static_resultset<T, true>; - friend struct connection; - friend struct statement; - resultset result_; - void check_columns_( system::error_code & ec, error_info & ei) - { - detail::check_columns(static_cast<T*>(nullptr), result_, ec, ei); - } -}; - -BOOST_SQLITE_END_NAMESPACE - -#endif //BOOST_SQLITE_STATIC_RESULTSET_HPP |