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Diffstat (limited to 'mysql/custom/traits.hxx')
-rw-r--r-- | mysql/custom/traits.hxx | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/mysql/custom/traits.hxx b/mysql/custom/traits.hxx new file mode 100644 index 0000000..bf4ceb4 --- /dev/null +++ b/mysql/custom/traits.hxx @@ -0,0 +1,89 @@ +// file : mysql/types/traits.hxx +// copyright : Copyright (c) 2009-2012 Code Synthesis Tools CC +// license : GNU GPL v2; see accompanying LICENSE file + +#ifndef TRAITS_HXX +#define TRAITS_HXX + +#include <limits> // std::numeric_limits +#include <sstream> +#include <cstring> // std::memcpy + +#include <odb/mysql/traits.hxx> + +#include "test.hxx" // point + +namespace odb +{ + namespace mysql + { + template <> + class value_traits<point, id_string> + { + public: + typedef point value_type; + typedef point query_type; + + typedef char* image_type; + + static void + set_value (point& v, + const details::buffer& b, + std::size_t n, + bool is_null) + { + if (is_null) + v = point (); + else + { + // Point format is "POINT(x y)". + // + std::istringstream is (std::string (b.data () + 6, n - 6)); + + is >> v.x; + is >> v.y; + } + } + + static void + set_image (details::buffer& b, + std::size_t& n, + bool& is_null, + const point& v) + { + is_null = false; + std::ostringstream os; + + // The formula for the number of decimla digits required is given in: + // + // http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2005/n1822.pdf + // + os.precision (std::numeric_limits<double>::digits10); + // os.precision (2 + std::numeric_limits<double>::digits * 301/1000); + + os << "POINT(" << v.x << ' ' << v.y << ')'; + + const std::string& s (os.str ()); + n = s.size (); + + if (n > b.capacity ()) + b.capacity (n); + + std::memcpy (b.data (), s.c_str (), n); + } + }; + + template <> + struct type_traits<point> + { + static const database_type_id db_type_id = id_string; + + struct conversion + { + static const char* to () {return "GeomFromText((?))";} + }; + }; + } +} + +#endif // TRAITS_HXX |