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Diffstat (limited to 'boost/property_tree/json_parser/detail/write.hpp')
| -rw-r--r-- | boost/property_tree/json_parser/detail/write.hpp | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/boost/property_tree/json_parser/detail/write.hpp b/boost/property_tree/json_parser/detail/write.hpp new file mode 100644 index 0000000000..bba10038bb --- /dev/null +++ b/boost/property_tree/json_parser/detail/write.hpp @@ -0,0 +1,168 @@ +// ---------------------------------------------------------------------------- +// Copyright (C) 2002-2006 Marcin Kalicinski +// +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) +// +// For more information, see www.boost.org +// ---------------------------------------------------------------------------- +#ifndef BOOST_PROPERTY_TREE_DETAIL_JSON_PARSER_WRITE_HPP_INCLUDED +#define BOOST_PROPERTY_TREE_DETAIL_JSON_PARSER_WRITE_HPP_INCLUDED + +#include <boost/property_tree/ptree.hpp> +#include <boost/next_prior.hpp> +#include <boost/type_traits/make_unsigned.hpp> +#include <string> +#include <ostream> +#include <iomanip> + +namespace boost { namespace property_tree { namespace json_parser +{ + + // Create necessary escape sequences from illegal characters + template<class Ch> + std::basic_string<Ch> create_escapes(const std::basic_string<Ch> &s) + { + std::basic_string<Ch> result; + typename std::basic_string<Ch>::const_iterator b = s.begin(); + typename std::basic_string<Ch>::const_iterator e = s.end(); + while (b != e) + { + typedef typename make_unsigned<Ch>::type UCh; + UCh c(*b); + // This assumes an ASCII superset. But so does everything in PTree. + // We escape everything outside ASCII, because this code can't + // handle high unicode characters. + if (c == 0x20 || c == 0x21 || (c >= 0x23 && c <= 0x2E) || + (c >= 0x30 && c <= 0x5B) || (c >= 0x5D && c <= 0xFF)) + result += *b; + else if (*b == Ch('\b')) result += Ch('\\'), result += Ch('b'); + else if (*b == Ch('\f')) result += Ch('\\'), result += Ch('f'); + else if (*b == Ch('\n')) result += Ch('\\'), result += Ch('n'); + else if (*b == Ch('\r')) result += Ch('\\'), result += Ch('r'); + else if (*b == Ch('\t')) result += Ch('\\'), result += Ch('t'); + else if (*b == Ch('/')) result += Ch('\\'), result += Ch('/'); + else if (*b == Ch('"')) result += Ch('\\'), result += Ch('"'); + else if (*b == Ch('\\')) result += Ch('\\'), result += Ch('\\'); + else + { + const char *hexdigits = "0123456789ABCDEF"; + unsigned long u = (std::min)(static_cast<unsigned long>( + static_cast<UCh>(*b)), + 0xFFFFul); + unsigned long d1 = u / 4096; u -= d1 * 4096; + unsigned long d2 = u / 256; u -= d2 * 256; + unsigned long d3 = u / 16; u -= d3 * 16; + unsigned long d4 = u; + result += Ch('\\'); result += Ch('u'); + result += Ch(hexdigits[d1]); result += Ch(hexdigits[d2]); + result += Ch(hexdigits[d3]); result += Ch(hexdigits[d4]); + } + ++b; + } + return result; + } + + template<class Ptree> + void write_json_helper(std::basic_ostream<typename Ptree::key_type::value_type> &stream, + const Ptree &pt, + int indent, bool pretty) + { + + typedef typename Ptree::key_type::value_type Ch; + typedef typename std::basic_string<Ch> Str; + + // Value or object or array + if (indent > 0 && pt.empty()) + { + // Write value + Str data = create_escapes(pt.template get_value<Str>()); + stream << Ch('"') << data << Ch('"'); + + } + else if (indent > 0 && pt.count(Str()) == pt.size()) + { + // Write array + stream << Ch('['); + if (pretty) stream << Ch('\n'); + typename Ptree::const_iterator it = pt.begin(); + for (; it != pt.end(); ++it) + { + if (pretty) stream << Str(4 * (indent + 1), Ch(' ')); + write_json_helper(stream, it->second, indent + 1, pretty); + if (boost::next(it) != pt.end()) + stream << Ch(','); + if (pretty) stream << Ch('\n'); + } + if (pretty) stream << Str(4 * indent, Ch(' ')); + stream << Ch(']'); + + } + else + { + // Write object + stream << Ch('{'); + if (pretty) stream << Ch('\n'); + typename Ptree::const_iterator it = pt.begin(); + for (; it != pt.end(); ++it) + { + if (pretty) stream << Str(4 * (indent + 1), Ch(' ')); + stream << Ch('"') << create_escapes(it->first) << Ch('"') << Ch(':'); + if (pretty) stream << Ch(' '); + write_json_helper(stream, it->second, indent + 1, pretty); + if (boost::next(it) != pt.end()) + stream << Ch(','); + if (pretty) stream << Ch('\n'); + } + if (pretty) stream << Str(4 * indent, Ch(' ')); + stream << Ch('}'); + } + + } + + // Verify if ptree does not contain information that cannot be written to json + template<class Ptree> + bool verify_json(const Ptree &pt, int depth) + { + + typedef typename Ptree::key_type::value_type Ch; + typedef typename std::basic_string<Ch> Str; + + // Root ptree cannot have data + if (depth == 0 && !pt.template get_value<Str>().empty()) + return false; + + // Ptree cannot have both children and data + if (!pt.template get_value<Str>().empty() && !pt.empty()) + return false; + + // Check children + typename Ptree::const_iterator it = pt.begin(); + for (; it != pt.end(); ++it) + if (!verify_json(it->second, depth + 1)) + return false; + + // Success + return true; + + } + + // Write ptree to json stream + template<class Ptree> + void write_json_internal(std::basic_ostream<typename Ptree::key_type::value_type> &stream, + const Ptree &pt, + const std::string &filename, + bool pretty) + { + if (!verify_json(pt, 0)) + BOOST_PROPERTY_TREE_THROW(json_parser_error("ptree contains data that cannot be represented in JSON format", filename, 0)); + write_json_helper(stream, pt, 0, pretty); + stream << std::endl; + if (!stream.good()) + BOOST_PROPERTY_TREE_THROW(json_parser_error("write error", filename, 0)); + } + +} } } + +#endif |