detail/typing/meta_check_context.hpp

0001 //
0002 // Copyright (c) 2019-2023 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
0003 //
0004 // Distributed under the Boost Software License, Version 1.0. (See accompanying
0005 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0006 //
0007
0008 #ifndef BOOST_MYSQL_DETAIL_TYPING_META_CHECK_CONTEXT_HPP
0009 #define BOOST_MYSQL_DETAIL_TYPING_META_CHECK_CONTEXT_HPP
0010
0011 #include <boost/mysql/client_errc.hpp>
0012 #include <boost/mysql/column_type.hpp>
0013 #include <boost/mysql/diagnostics.hpp>
0014 #include <boost/mysql/error_code.hpp>
0015 #include <boost/mysql/metadata.hpp>
0016 #include <boost/mysql/metadata_collection_view.hpp>
0017 #include <boost/mysql/string_view.hpp>
0018
0019 #include <boost/mysql/detail/access.hpp>
0020 #include <boost/mysql/detail/config.hpp>
0021 #include <boost/mysql/detail/typing/pos_map.hpp>
0022
0023 #include <memory>
0024 #include <sstream>
0025
0026 namespace boost {
0027 namespace mysql {
0028 namespace detail {
0029
0030 inline const char* column_type_to_str(const metadata& meta) noexcept
0031 {
0032     switch (meta.type())
0033     {
0034     case column_type::tinyint: return meta.is_unsigned() ? "TINYINT UNSIGNED" : "TINYINT";
0035     case column_type::smallint: return meta.is_unsigned() ? "SMALLINT UNSIGNED" : "SMALLINT";
0036     case column_type::mediumint: return meta.is_unsigned() ? "MEDIUMINT UNSIGNED" : "MEDIUMINT";
0037     case column_type::int_: return meta.is_unsigned() ? "INT UNSIGNED" : "INT";
0038     case column_type::bigint: return meta.is_unsigned() ? "BIGINT UNSIGNED" : "BIGINT";
0039     case column_type::float_: return "FLOAT";
0040     case column_type::double_: return "DOUBLE";
0041     case column_type::decimal: return "DECIMAL";
0042     case column_type::bit: return "BIT";
0043     case column_type::year: return "YEAR";
0044     case column_type::time: return "TIME";
0045     case column_type::date: return "DATE";
0046     case column_type::datetime: return "DATETIME";
0047     case column_type::timestamp: return "TIMESTAMP";
0048     case column_type::char_: return "CHAR";
0049     case column_type::varchar: return "VARCHAR";
0050     case column_type::binary: return "BINARY";
0051     case column_type::varbinary: return "VARBINARY";
0052     case column_type::text: return "TEXT";
0053     case column_type::blob: return "BLOB";
0054     case column_type::enum_: return "ENUM";
0055     case column_type::set: return "SET";
0056     case column_type::json: return "JSON";
0057     case column_type::geometry: return "GEOMETRY";
0058     default: return "<unknown column type>";
0059     }
0060 }
0061
0062 class meta_check_context
0063 {
0064     std::unique_ptr<std::ostringstream> errors_;
0065     std::size_t current_index_{};
0066     span<const std::size_t> pos_map_;
0067     name_table_t name_table_;
0068     metadata_collection_view meta_{};
0069     bool nullability_checked_{};
0070
0071     std::ostringstream& add_error()
0072     {
0073         if (!errors_)
0074             errors_.reset(new std::ostringstream);
0075         else
0076             *errors_ << '\n';
0077         return *errors_;
0078     }
0079
0080     void insert_field_name(std::ostringstream& os)
0081     {
0082         if (has_field_names(name_table_))
0083             os << "'" << name_table_[current_index_] << "'";
0084         else
0085             os << "in position " << current_index_;
0086     }
0087
0088 public:
0089     meta_check_context(
0090         span<const std::size_t> pos_map,
0091         name_table_t name_table,
0092         metadata_collection_view meta
0093     ) noexcept
0094         : pos_map_(pos_map), name_table_(name_table), meta_(meta)
0095     {
0096     }
0097
0098     // Accessors
0099     const metadata& current_meta() const noexcept { return map_metadata(pos_map_, current_index_, meta_); }
0100     bool is_current_field_absent() const noexcept { return pos_map_[current_index_] == pos_absent; }
0101
0102     // Iteration
0103     void advance() noexcept
0104     {
0105         nullability_checked_ = false;
0106         ++current_index_;
0107     }
0108
0109     // Nullability
0110     void set_nullability_checked() noexcept { nullability_checked_ = true; }
0111     bool nullability_checked() const noexcept { return nullability_checked_; }
0112
0113     // Error reporting
0114     BOOST_MYSQL_DECL
0115     void add_field_absent_error();
0116
0117     BOOST_MYSQL_DECL
0118     void add_type_mismatch_error(const char* cpp_type_name);
0119
0120     BOOST_MYSQL_DECL
0121     void add_nullability_error();
0122
0123     BOOST_MYSQL_DECL
0124     error_code check_errors(diagnostics& diag) const;
0125 };
0126
0127 }  // namespace detail
0128 }  // namespace mysql
0129 }  // namespace boost
0130
0131 #ifdef BOOST_MYSQL_HEADER_ONLY
0132 #include <boost/mysql/impl/meta_check_context.ipp>
0133 #endif
0134
0135 #endif