mapnik/src/image_options.cpp
2021-01-05 14:39:07 +00:00

123 lines
3.8 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2021 Artem Pavlenko
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*****************************************************************************/
#include <mapnik/image_options.hpp>
#include <mapnik/warning.hpp>
MAPNIK_DISABLE_WARNING_PUSH
#include <mapnik/warning_ignore.hpp>
#include <boost/spirit/home/x3.hpp>
#include <boost/fusion/include/std_pair.hpp>
MAPNIK_DISABLE_WARNING_POP
#if defined(HAVE_PNG)
extern "C"
{
#include <png.h>
}
#endif // HAVE_PNG
namespace mapnik { namespace grammar {
namespace x3 = boost::spirit::x3;
using x3::lit;
using x3::ascii::char_;
using pair_type = std::pair<std::string, boost::optional<std::string>>;
x3::rule<class image_options, image_options_map> const image_options("image options");
x3::rule<class key_value, pair_type> const key_value("key_value");
x3::rule<class key, std::string> const key("key");
x3::rule<class value, std::string> const value("value");
auto const key_def = char_("a-zA-Z_") > *char_("a-zA-Z_0-9\\.\\-");
auto const value_def = +char_("a-zA-Z_0-9\\.\\-|");
auto const key_value_def = key > -('=' > value);
auto const image_options_def = key_value % lit(':');
BOOST_SPIRIT_DEFINE(key);
BOOST_SPIRIT_DEFINE(value);
BOOST_SPIRIT_DEFINE(key_value);
BOOST_SPIRIT_DEFINE(image_options);
} // grammar
image_options_map parse_image_options(std::string const& str)
{
auto begin = str.begin();
auto const end = str.end();
using boost::spirit::x3::space;
using mapnik::grammar::image_options;
image_options_map options;
try
{
bool success = boost::spirit::x3::phrase_parse(begin, end, image_options, space, options);
if (!success || begin != end)
{
throw std::runtime_error("Can't parse image options: " + str);
}
}
catch (boost::spirit::x3::expectation_failure<std::string> const& ex)
{
throw std::runtime_error("Can't parse image options: " + str + " " + ex.what());
}
return options; // RVO
}
#if defined(HAVE_PNG)
int parse_png_filters(std::string const& str)
{
auto begin = str.begin();
auto const end = str.end();
using boost::spirit::x3::space;
using boost::spirit::x3::symbols;
symbols<int> filter;
filter.add
("none", PNG_FILTER_NONE)
("sub", PNG_FILTER_SUB)
("up", PNG_FILTER_UP)
("avg", PNG_FILTER_AVG)
("paeth", PNG_FILTER_PAETH)
;
std::vector<int> opts;
try
{
bool success = boost::spirit::x3::phrase_parse(begin, end, filter % "|" , space , opts);
if (!success || begin != end)
{
throw std::runtime_error("Can't parse PNG filters: " + str);
}
}
catch (boost::spirit::x3::expectation_failure<std::string> const& ex)
{
throw std::runtime_error("Can't parse PNG filters: " + str + " " + ex.what());
}
int filters = 0;
std::for_each(opts.begin(), opts.end(), [&filters] (int f) { filters |= f;});
return filters;
}
#endif // HAVE_PNG
} // ns mapnik