Chris@16: // ----------------------------------------------------------------------------
Chris@16: // Copyright (C) 2002-2006 Marcin Kalicinski
Chris@16: //
Chris@101: // Distributed under the Boost Software License, Version 1.0.
Chris@101: // (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //
Chris@16: // For more information, see www.boost.org
Chris@16: // ----------------------------------------------------------------------------
Chris@16: #ifndef BOOST_PROPERTY_TREE_DETAIL_JSON_PARSER_READ_HPP_INCLUDED
Chris@16: #define BOOST_PROPERTY_TREE_DETAIL_JSON_PARSER_READ_HPP_INCLUDED
Chris@16: 
Chris@16: //#define BOOST_SPIRIT_DEBUG
Chris@16: 
Chris@16: #include <boost/property_tree/ptree.hpp>
Chris@16: #include <boost/property_tree/detail/ptree_utils.hpp>
Chris@16: #include <boost/property_tree/detail/json_parser_error.hpp>
Chris@16: #include <boost/spirit/include/classic.hpp>
Chris@16: #include <boost/limits.hpp>
Chris@16: #include <string>
Chris@16: #include <locale>
Chris@16: #include <istream>
Chris@16: #include <vector>
Chris@16: #include <algorithm>
Chris@16: 
Chris@16: namespace boost { namespace property_tree { namespace json_parser
Chris@16: {
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////
Chris@16:     // Json parser context
Chris@101: 
Chris@16:     template<class Ptree>
Chris@16:     struct context
Chris@16:     {
Chris@101: 	typedef typename Ptree::key_type Str;
Chris@101:         typedef typename Str::value_type Ch;
Chris@101:         typedef typename std::vector<Ch>::iterator It;
Chris@16: 
Chris@16:         Str string;
Chris@16:         Str name;
Chris@16:         Ptree root;
Chris@16:         std::vector<Ptree *> stack;
Chris@16: 
Chris@16:         struct a_object_s
Chris@16:         {
Chris@16:             context &c;
Chris@16:             a_object_s(context &c): c(c) { }
Chris@16:             void operator()(Ch) const
Chris@16:             {
Chris@16:                 if (c.stack.empty())
Chris@16:                     c.stack.push_back(&c.root);
Chris@16:                 else
Chris@16:                 {
Chris@16:                     Ptree *parent = c.stack.back();
Chris@16:                     Ptree *child = &parent->push_back(std::make_pair(c.name, Ptree()))->second;
Chris@16:                     c.stack.push_back(child);
Chris@16:                     c.name.clear();
Chris@16:                 }
Chris@16:             }
Chris@16:         };
Chris@101: 
Chris@16:         struct a_object_e
Chris@16:         {
Chris@16:             context &c;
Chris@16:             a_object_e(context &c): c(c) { }
Chris@16:             void operator()(Ch) const
Chris@16:             {
Chris@16:                 BOOST_ASSERT(c.stack.size() >= 1);
Chris@16:                 c.stack.pop_back();
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16:         struct a_name
Chris@16:         {
Chris@16:             context &c;
Chris@16:             a_name(context &c): c(c) { }
Chris@16:             void operator()(It, It) const
Chris@16:             {
Chris@16:                 c.name.swap(c.string);
Chris@16:                 c.string.clear();
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16:         struct a_string_val
Chris@16:         {
Chris@16:             context &c;
Chris@16:             a_string_val(context &c): c(c) { }
Chris@16:             void operator()(It, It) const
Chris@16:             {
Chris@16:                 BOOST_ASSERT(c.stack.size() >= 1);
Chris@16:                 c.stack.back()->push_back(std::make_pair(c.name, Ptree(c.string)));
Chris@16:                 c.name.clear();
Chris@16:                 c.string.clear();
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16:         struct a_literal_val
Chris@16:         {
Chris@16:             context &c;
Chris@16:             a_literal_val(context &c): c(c) { }
Chris@16:             void operator()(It b, It e) const
Chris@16:             {
Chris@16:                 BOOST_ASSERT(c.stack.size() >= 1);
Chris@16:                 c.stack.back()->push_back(std::make_pair(c.name,
Chris@16:                     Ptree(Str(b, e))));
Chris@16:                 c.name.clear();
Chris@16:                 c.string.clear();
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16:         struct a_char
Chris@16:         {
Chris@16:             context &c;
Chris@16:             a_char(context &c): c(c) { }
Chris@101:             void operator()(It b, It) const
Chris@16:             {
Chris@16:                 c.string += *b;
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16:         struct a_escape
Chris@16:         {
Chris@16:             context &c;
Chris@16:             a_escape(context &c): c(c) { }
Chris@16:             void operator()(Ch ch) const
Chris@16:             {
Chris@16:                 switch (ch)
Chris@16:                 {
Chris@16:                     case Ch('\"'): c.string += Ch('\"'); break;
Chris@16:                     case Ch('\\'): c.string += Ch('\\'); break;
Chris@16:                     case Ch('/'): c.string += Ch('/'); break;
Chris@16:                     case Ch('b'): c.string += Ch('\b'); break;
Chris@16:                     case Ch('f'): c.string += Ch('\f'); break;
Chris@16:                     case Ch('n'): c.string += Ch('\n'); break;
Chris@16:                     case Ch('r'): c.string += Ch('\r'); break;
Chris@16:                     case Ch('t'): c.string += Ch('\t'); break;
Chris@16:                     default: BOOST_ASSERT(0);
Chris@16:                 }
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16:         struct a_unicode
Chris@16:         {
Chris@16:             context &c;
Chris@16:             a_unicode(context &c): c(c) { }
Chris@16:             void operator()(unsigned long u) const
Chris@16:             {
Chris@16:                 u = (std::min)(u, static_cast<unsigned long>((std::numeric_limits<Ch>::max)()));
Chris@16:                 c.string += Ch(u);
Chris@16:             }
Chris@16:         };
Chris@16: 
Chris@16:     };
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////
Chris@16:     // Json grammar
Chris@16: 
Chris@16:     template<class Ptree>
Chris@16:     struct json_grammar :
Chris@16:         public boost::spirit::classic::grammar<json_grammar<Ptree> >
Chris@16:     {
Chris@101: 
Chris@16:         typedef context<Ptree> Context;
Chris@101:         typedef typename Ptree::key_type Str;
Chris@101:         typedef typename Str::value_type Ch;
Chris@16: 
Chris@16:         mutable Context c;
Chris@101: 
Chris@16:         template<class Scanner>
Chris@16:         struct definition
Chris@16:         {
Chris@101: 
Chris@16:             boost::spirit::classic::rule<Scanner>
Chris@16:                 root, object, member, array, item, value, string, number;
Chris@16:             boost::spirit::classic::rule<
Chris@16:                 typename boost::spirit::classic::lexeme_scanner<Scanner>::type>
Chris@16:                 character, escape;
Chris@16: 
Chris@16:             definition(const json_grammar &self)
Chris@16:             {
Chris@16: 
Chris@16:                 using namespace boost::spirit::classic;
Chris@16:                 // There's a boost::assertion too, so another explicit using
Chris@16:                 // here:
Chris@16:                 using boost::spirit::classic::assertion;
Chris@16: 
Chris@16:                 // Assertions
Chris@16:                 assertion<std::string> expect_root("expected object or array");
Chris@16:                 assertion<std::string> expect_eoi("expected end of input");
Chris@16:                 assertion<std::string> expect_objclose("expected ',' or '}'");
Chris@16:                 assertion<std::string> expect_arrclose("expected ',' or ']'");
Chris@16:                 assertion<std::string> expect_name("expected object name");
Chris@16:                 assertion<std::string> expect_colon("expected ':'");
Chris@16:                 assertion<std::string> expect_value("expected value");
Chris@16:                 assertion<std::string> expect_escape("invalid escape sequence");
Chris@16: 
Chris@16:                 // JSON grammar rules
Chris@101:                 root
Chris@101:                     =   expect_root(object | array)
Chris@16:                         >> expect_eoi(end_p)
Chris@16:                         ;
Chris@101: 
Chris@101:                 object
Chris@16:                     =   ch_p('{')[typename Context::a_object_s(self.c)]
Chris@101:                         >> (ch_p('}')[typename Context::a_object_e(self.c)]
Chris@16:                            | (list_p(member, ch_p(','))
Chris@16:                               >> expect_objclose(ch_p('}')[typename Context::a_object_e(self.c)])
Chris@16:                              )
Chris@16:                            )
Chris@16:                         ;
Chris@101: 
Chris@101:                 member
Chris@101:                     =   expect_name(string[typename Context::a_name(self.c)])
Chris@101:                         >> expect_colon(ch_p(':'))
Chris@16:                         >> expect_value(value)
Chris@16:                         ;
Chris@101: 
Chris@101:                 array
Chris@16:                     =   ch_p('[')[typename Context::a_object_s(self.c)]
Chris@101:                         >> (ch_p(']')[typename Context::a_object_e(self.c)]
Chris@16:                             | (list_p(item, ch_p(','))
Chris@16:                                >> expect_arrclose(ch_p(']')[typename Context::a_object_e(self.c)])
Chris@16:                               )
Chris@16:                            )
Chris@16:                     ;
Chris@16: 
Chris@101:                 item
Chris@16:                     =   expect_value(value)
Chris@16:                         ;
Chris@16: 
Chris@101:                 value
Chris@101:                     =   string[typename Context::a_string_val(self.c)]
Chris@16:                         | (number | str_p("true") | "false" | "null")[typename Context::a_literal_val(self.c)]
Chris@101:                         | object
Chris@16:                         | array
Chris@16:                         ;
Chris@101: 
Chris@101:                 number
Chris@16:                     =   !ch_p("-") >>
Chris@16:                         (ch_p("0") | (range_p(Ch('1'), Ch('9')) >> *digit_p)) >>
Chris@16:                         !(ch_p(".") >> +digit_p) >>
Chris@101:                         !(chset_p(detail::widen<Str>("eE").c_str()) >>
Chris@101:                           !chset_p(detail::widen<Str>("-+").c_str()) >>
Chris@16:                           +digit_p)
Chris@16:                         ;
Chris@16: 
Chris@16:                 string
Chris@16:                     =   +(lexeme_d[confix_p('\"', *character, '\"')])
Chris@16:                         ;
Chris@16: 
Chris@16:                 character
Chris@16:                     =   (anychar_p - "\\" - "\"")
Chris@16:                             [typename Context::a_char(self.c)]
Chris@16:                     |   ch_p("\\") >> expect_escape(escape)
Chris@16:                     ;
Chris@16: 
Chris@16:                 escape
Chris@101:                     =   chset_p(detail::widen<Str>("\"\\/bfnrt").c_str())
Chris@16:                             [typename Context::a_escape(self.c)]
Chris@16:                     |   'u' >> uint_parser<unsigned long, 16, 4, 4>()
Chris@16:                             [typename Context::a_unicode(self.c)]
Chris@16:                     ;
Chris@16: 
Chris@16:                 // Debug
Chris@16:                 BOOST_SPIRIT_DEBUG_RULE(root);
Chris@16:                 BOOST_SPIRIT_DEBUG_RULE(object);
Chris@16:                 BOOST_SPIRIT_DEBUG_RULE(member);
Chris@16:                 BOOST_SPIRIT_DEBUG_RULE(array);
Chris@16:                 BOOST_SPIRIT_DEBUG_RULE(item);
Chris@16:                 BOOST_SPIRIT_DEBUG_RULE(value);
Chris@16:                 BOOST_SPIRIT_DEBUG_RULE(string);
Chris@16:                 BOOST_SPIRIT_DEBUG_RULE(number);
Chris@16:                 BOOST_SPIRIT_DEBUG_RULE(escape);
Chris@16:                 BOOST_SPIRIT_DEBUG_RULE(character);
Chris@16: 
Chris@16:             }
Chris@16: 
Chris@16:             const boost::spirit::classic::rule<Scanner> &start() const
Chris@16:             {
Chris@16:                 return root;
Chris@16:             }
Chris@16: 
Chris@16:         };
Chris@16: 
Chris@16:     };
Chris@16: 
Chris@16:     template<class It, class Ch>
Chris@16:     unsigned long count_lines(It begin, It end)
Chris@16:     {
Chris@16:         return static_cast<unsigned long>(std::count(begin, end, Ch('\n')) + 1);
Chris@16:     }
Chris@16: 
Chris@16:     template<class Ptree>
Chris@16:     void read_json_internal(std::basic_istream<typename Ptree::key_type::value_type> &stream,
Chris@16:                             Ptree &pt,
Chris@16:                             const std::string &filename)
Chris@16:     {
Chris@16: 
Chris@16:         using namespace boost::spirit::classic;
Chris@16:         typedef typename Ptree::key_type::value_type Ch;
Chris@16:         typedef typename std::vector<Ch>::iterator It;
Chris@16: 
Chris@16:         // Load data into vector
Chris@16:         std::vector<Ch> v(std::istreambuf_iterator<Ch>(stream.rdbuf()),
Chris@16:                           std::istreambuf_iterator<Ch>());
Chris@16:         if (!stream.good())
Chris@16:             BOOST_PROPERTY_TREE_THROW(json_parser_error("read error", filename, 0));
Chris@101: 
Chris@16:         // Prepare grammar
Chris@16:         json_grammar<Ptree> g;
Chris@16: 
Chris@16:         // Parse
Chris@16:         try
Chris@16:         {
Chris@101:             parse_info<It> pi = parse(v.begin(), v.end(), g,
Chris@16:                                       space_p | comment_p("//") | comment_p("/*", "*/"));
Chris@16:             if (!pi.hit || !pi.full)
Chris@16:                 BOOST_PROPERTY_TREE_THROW((parser_error<std::string, It>(v.begin(), "syntax error")));
Chris@16:         }
Chris@16:         catch (parser_error<std::string, It> &e)
Chris@16:         {
Chris@16:             BOOST_PROPERTY_TREE_THROW(json_parser_error(e.descriptor, filename, count_lines<It, Ch>(v.begin(), e.where)));
Chris@16:         }
Chris@16: 
Chris@16:         // Swap grammar context root and pt
Chris@16:         pt.swap(g.c.root);
Chris@16: 
Chris@16:     }
Chris@16: 
Chris@16: } } }
Chris@16: 
Chris@16: #endif