gfx/graphite2/src/json.cpp

   1 /*  GRAPHITE2 LICENSING
   2
   3     Copyright 2011, SIL International
   4     All rights reserved.
   5
   6     This library is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU Lesser General Public License as published
   8     by the Free Software Foundation; either version 2.1 of License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14     Lesser General Public License for more details.
  15
  16     You should also have received a copy of the GNU Lesser General Public
  17     License along with this library in the file named "LICENSE".
  18     If not, write to the Free Software Foundation, 51 Franklin Street,
  19     Suite 500, Boston, MA 02110-1335, USA or visit their web page on the
  20     internet at http://www.fsf.org/licenses/lgpl.html.
  21
  22 Alternatively, the contents of this file may be used under the terms of the
  23 Mozilla Public License (http://mozilla.org/MPL) or the GNU General Public
  24 License, as published by the Free Software Foundation, either version 2
  25 of the License or (at your option) any later version.
  26 */
  27 // JSON debug logging
  28 // Author: Tim Eves
  29
  30 #if !defined GRAPHITE2_NTRACING
  31
  32 #include <cstdio>
  33 #include <limits>
  34 #include "inc/json.h"
  35
  36 #if defined(_MSC_VER)
  37 #define FORMAT_INTMAX "%lli"
  38 #define FORMAT_UINTMAX "%llu"
  39 #else
  40 #define FORMAT_INTMAX "%ji"
  41 #define FORMAT_UINTMAX "%ju"
  42 #endif
  43
  44 using namespace graphite2;
  45
  46 namespace
  47 {
  48     enum
  49     {
  50         seq = ',',
  51         obj='}', member=':', empty_obj='{',
  52         arr=']', empty_arr='['
  53     };
  54 }
  55
  56 const std::nullptr_t json::null = nullptr;
  57
  58 inline
  59 void json::context(const char current) throw()
  60 {
  61     fprintf(_stream, "%c", *_context);
  62     indent();
  63     *_context = current;
  64 }
  65
  66
  67 void json::indent(const int d) throw()
  68 {
  69     if (*_context == member || (_flatten  && _flatten < _context))
  70         fputc(' ', _stream);
  71     else
  72         fprintf(_stream,  "\n%*s",  4*int(_context - _contexts + d), "");
  73 }
  74
  75
  76 inline
  77 void json::push_context(const char prefix, const char suffix) throw()
  78 {
  79     assert(_context - _contexts < ptrdiff_t(sizeof _contexts));
  80
  81     if (_context == _contexts)
  82         *_context = suffix;
  83     else
  84         context(suffix);
  85     *++_context = prefix;
  86 }
  87
  88
  89 void json::pop_context() throw()
  90 {
  91     assert(_context > _contexts);
  92
  93     if (*_context == seq)   indent(-1);
  94     else                    fputc(*_context, _stream);
  95
  96     fputc(*--_context, _stream);
  97     if (_context == _contexts)  fputc('\n', _stream);
  98     fflush(_stream);
  99
 100     if (_flatten >= _context)   _flatten = 0;
 101     *_context = seq;
 102 }
 103
 104
 105 // These four functions cannot be inlined as pointers to these
 106 // functions are needed for operator << (_context_t) to work.
 107 void json::flat(json & j) throw()   { if (!j._flatten)  j._flatten = j._context; }
 108 void json::close(json & j) throw()  { j.pop_context(); }
 109 void json::object(json & j) throw() { j.push_context('{', '}'); }
 110 void json::array(json & j) throw()  { j.push_context('[', ']'); }
 111 void json::item(json & j) throw()
 112 {
 113     while (j._context > j._contexts+1 && j._context[-1] != arr)
 114         j.pop_context();
 115 }
 116
 117
 118 json & json::operator << (json::string s) throw()
 119 {
 120     const char ctxt = _context[-1] == obj ? *_context == member ? seq : member : seq;
 121     context(ctxt);
 122     fprintf(_stream, "\"%s\"", s);
 123     if (ctxt == member) fputc(' ', _stream);
 124
 125     return *this;
 126 }
 127
 128 json & json::operator << (json::number f) throw()
 129 {
 130     context(seq);
 131     if (std::numeric_limits<json::number>::infinity() == f)
 132         fputs("Infinity", _stream);
 133     else if (-std::numeric_limits<json::number>::infinity() == f)
 134         fputs("-Infinity", _stream);
 135     else if (std::numeric_limits<json::number>::quiet_NaN() == f ||
 136             std::numeric_limits<json::number>::signaling_NaN() == f)
 137         fputs("NaN", _stream);
 138     else
 139         fprintf(_stream, "%g", f);
 140     return *this;
 141 }
 142 json & json::operator << (json::integer d) throw()  { context(seq); fprintf(_stream, FORMAT_INTMAX, intmax_t(d)); return *this; }
 143 json & json::operator << (json::integer_u d) throw()  { context(seq); fprintf(_stream, FORMAT_UINTMAX, uintmax_t(d)); return *this; }
 144 json & json::operator << (json::boolean b) throw()  { context(seq); fputs(b ? "true" : "false", _stream); return *this; }
 145 json & json::operator << (std::nullptr_t)  throw()  { context(seq); fputs("null",_stream); return *this; }
 146
 147 #endif