/srv/osrm/osrm-backend/include/util
Edit: /srv/osrm/osrm-backend/include/util/json_renderer.hpp (4160B)
// based on
// https://svn.apache.org/repos/asf/mesos/tags/release-0.9.0-incubating-RC0/src/common/json.hpp
#ifndef JSON_RENDERER_HPP
#define JSON_RENDERER_HPP
#include "util/string_util.hpp"
#include "osrm/json_container.hpp"
#include
#include
#include
#include
#include
#include
#include
namespace osrm::util::json
{
template struct Renderer
{
explicit Renderer(Out &_out) : out(_out) {}
void operator()(const String &string)
{
write('"');
// here we assume that vast majority of strings don't need to be escaped,
// so we check it first and escape only if needed
if (RequiresJSONStringEscaping(string.value))
{
std::string escaped;
// just a guess that 16 bytes for escaped characters will be enough to avoid
// reallocations
escaped.reserve(string.value.size() + 16);
EscapeJSONString(string.value, escaped);
write(escaped);
}
else
{
write(string.value);
}
write('"');
}
void operator()(const Number &number)
{
// we don't want to print NaN or Infinity
BOOST_ASSERT(std::isfinite(number.value));
// `fmt::memory_buffer` stores first 500 bytes in the object itself(i.e. on stack in this
// case) and then grows using heap if needed
fmt::memory_buffer buffer;
fmt::format_to(std::back_inserter(buffer), FMT_COMPILE("{:.10g}"), number.value);
write(buffer.data(), buffer.size());
}
void operator()(const Object &object)
{
write('{');
for (auto it = object.values.begin(), end = object.values.end(); it != end;)
{
write('\"');
write(it->first);
write<>("\":");
mapbox::util::apply_visitor(Renderer(out), it->second);
if (++it != end)
{
write(',');
}
}
write('}');
}
void operator()(const Array &array)
{
write('[');
for (auto it = array.values.cbegin(), end = array.values.cend(); it != end;)
{
mapbox::util::apply_visitor(Renderer(out), *it);
if (++it != end)
{
write(',');
}
}
write(']');
}
void operator()(const True &) { write<>("true"); }
void operator()(const False &) { write<>("false"); }
void operator()(const Null &) { write<>("null"); }
private:
void write(const std::string &str);
void write(const char *str, size_t size);
void write(char ch);
template void write(const char (&str)[StrLength])
{
write(str, StrLength - 1);
}
private:
Out &out;
};
template <> void Renderer>::write(const std::string &str)
{
out.insert(out.end(), str.begin(), str.end());
}
template <> void Renderer>::write(const char *str, size_t size)
{
out.insert(out.end(), str, str + size);
}
template <> void Renderer>::write(char ch) { out.push_back(ch); }
template <> void Renderer::write(const std::string &str) { out << str; }
template <> void Renderer::write(const char *str, size_t size)
{
out.write(str, size);
}
template <> void Renderer::write(char ch) { out << ch; }
template <> void Renderer::write(const std::string &str) { out += str; }
template <> void Renderer::write(const char *str, size_t size)
{
out.append(str, size);
}
template <> void Renderer::write(char ch) { out += ch; }
inline void render(std::ostream &out, const Object &object)
{
Renderer renderer(out);
renderer(object);
}
inline void render(std::string &out, const Object &object)
{
Renderer renderer(out);
renderer(object);
}
inline void render(std::vector &out, const Object &object)
{
Renderer renderer(out);
renderer(object);
}
} // namespace osrm::util::json
#endif // JSON_RENDERER_HPP