#ifndef OSMIUM_GEOM_WKB_HPP #define OSMIUM_GEOM_WKB_HPP /* This file is part of Osmium (http://osmcode.org/libosmium). Copyright 2013-2018 Jochen Topf and others (see README). Boost Software License - Version 1.0 - August 17th, 2003 Permission is hereby granted, free of charge, to any person or organization obtaining a copy of the software and accompanying documentation covered by this license (the "Software") to use, reproduce, display, distribute, execute, and transmit the Software, and to prepare derivative works of the Software, and to permit third-parties to whom the Software is furnished to do so, all subject to the following: The copyright notices in the Software and this entire statement, including the above license grant, this restriction and the following disclaimer, must be included in all copies of the Software, in whole or in part, and all derivative works of the Software, unless such copies or derivative works are solely in the form of machine-executable object code generated by a source language processor. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #include #include #include #include #include #include #include #include namespace osmium { namespace geom { enum class wkb_type : bool { wkb = false, ewkb = true }; // enum class wkb_type enum class out_type : bool { binary = false, hex = true }; // enum class out_type namespace detail { template inline void str_push(std::string& str, T data) { str.append(reinterpret_cast(&data), sizeof(T)); } inline std::string convert_to_hex(const std::string& str) { static const char* lookup_hex = "0123456789ABCDEF"; std::string out; out.reserve(str.size() * 2); for (char c : str) { out += lookup_hex[(static_cast(c) >> 4u) & 0xfu]; out += lookup_hex[ static_cast(c) & 0xfu]; } return out; } class WKBFactoryImpl { /** * Type of WKB geometry. * These definitions are from * 99-049_OpenGIS_Simple_Features_Specification_For_SQL_Rev_1.1.pdf (for WKB) * and https://trac.osgeo.org/postgis/browser/trunk/doc/ZMSgeoms.txt (for EWKB). * They are used to encode geometries into the WKB format. */ enum wkbGeometryType : uint32_t { wkbPoint = 1, wkbLineString = 2, wkbPolygon = 3, wkbMultiPoint = 4, wkbMultiLineString = 5, wkbMultiPolygon = 6, wkbGeometryCollection = 7, // SRID-presence flag (EWKB) wkbSRID = 0x20000000 }; // enum wkbGeometryType /** * Byte order marker in WKB geometry. */ enum class wkb_byte_order_type : uint8_t { XDR = 0, // Big Endian NDR = 1 // Little Endian }; // enum class wkb_byte_order_type std::string m_data; uint32_t m_points = 0; int m_srid; wkb_type m_wkb_type; out_type m_out_type; std::size_t m_linestring_size_offset = 0; std::size_t m_polygons = 0; std::size_t m_rings = 0; std::size_t m_multipolygon_size_offset = 0; std::size_t m_polygon_size_offset = 0; std::size_t m_ring_size_offset = 0; std::size_t header(std::string& str, wkbGeometryType type, bool add_length) const { #if __BYTE_ORDER == __LITTLE_ENDIAN str_push(str, wkb_byte_order_type::NDR); #else str_push(str, wkb_byte_order_type::XDR); #endif if (m_wkb_type == wkb_type::ewkb) { str_push(str, type | wkbSRID); str_push(str, m_srid); } else { str_push(str, type); } const std::size_t offset = str.size(); if (add_length) { str_push(str, static_cast(0)); } return offset; } void set_size(const std::size_t offset, const std::size_t size) { if (size > std::numeric_limits::max()) { throw geometry_error{"Too many points in geometry"}; } const auto s = static_cast(size); std::copy_n(reinterpret_cast(&s), sizeof(uint32_t), &m_data[offset]); } public: using point_type = std::string; using linestring_type = std::string; using polygon_type = std::string; using multipolygon_type = std::string; using ring_type = std::string; explicit WKBFactoryImpl(int srid, wkb_type wtype = wkb_type::wkb, out_type otype = out_type::binary) : m_srid(srid), m_wkb_type(wtype), m_out_type(otype) { } /* Point */ point_type make_point(const osmium::geom::Coordinates& xy) const { std::string data; header(data, wkbPoint, false); str_push(data, xy.x); str_push(data, xy.y); if (m_out_type == out_type::hex) { return convert_to_hex(data); } return data; } /* LineString */ void linestring_start() { m_data.clear(); m_linestring_size_offset = header(m_data, wkbLineString, true); } void linestring_add_location(const osmium::geom::Coordinates& xy) { str_push(m_data, xy.x); str_push(m_data, xy.y); } linestring_type linestring_finish(std::size_t num_points) { set_size(m_linestring_size_offset, num_points); std::string data; using std::swap; swap(data, m_data); if (m_out_type == out_type::hex) { return convert_to_hex(data); } return data; } /* MultiPolygon */ void multipolygon_start() { m_data.clear(); m_polygons = 0; m_multipolygon_size_offset = header(m_data, wkbMultiPolygon, true); } void multipolygon_polygon_start() { ++m_polygons; m_rings = 0; m_polygon_size_offset = header(m_data, wkbPolygon, true); } void multipolygon_polygon_finish() { set_size(m_polygon_size_offset, m_rings); } void multipolygon_outer_ring_start() { ++m_rings; m_points = 0; m_ring_size_offset = m_data.size(); str_push(m_data, static_cast(0)); } void multipolygon_outer_ring_finish() { set_size(m_ring_size_offset, m_points); } void multipolygon_inner_ring_start() { ++m_rings; m_points = 0; m_ring_size_offset = m_data.size(); str_push(m_data, static_cast(0)); } void multipolygon_inner_ring_finish() { set_size(m_ring_size_offset, m_points); } void multipolygon_add_location(const osmium::geom::Coordinates& xy) { str_push(m_data, xy.x); str_push(m_data, xy.y); ++m_points; } multipolygon_type multipolygon_finish() { set_size(m_multipolygon_size_offset, m_polygons); std::string data; using std::swap; swap(data, m_data); if (m_out_type == out_type::hex) { return convert_to_hex(data); } return data; } }; // class WKBFactoryImpl } // namespace detail template using WKBFactory = GeometryFactory; } // namespace geom } // namespace osmium #endif // OSMIUM_GEOM_WKB_HPP