1// Copyright 2007-2010 Baptiste Lepilleur
2// Distributed under MIT license, or public domain if desired and
3// recognized in your jurisdiction.
4// See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE
5
6#ifndef LIB_JSONCPP_JSON_TOOL_H_INCLUDED
7# define LIB_JSONCPP_JSON_TOOL_H_INCLUDED
8
9/* This header provides common string manipulation support, such as UTF-8,
10 * portable conversion from/to string...
11 *
12 * It is an internal header that must not be exposed.
13 */
14
15namespace Json {
16
17/// Converts a unicode code-point to UTF-8.
18static inline std::string
19codePointToUTF8(unsigned int cp)
20{
21   std::string result;
22
23   // based on description from http://en.wikipedia.org/wiki/UTF-8
24
25   if (cp <= 0x7f)
26   {
27      result.resize(1);
28      result[0] = static_cast<char>(cp);
29   }
30   else if (cp <= 0x7FF)
31   {
32      result.resize(2);
33      result[1] = static_cast<char>(0x80 | (0x3f & cp));
34      result[0] = static_cast<char>(0xC0 | (0x1f & (cp >> 6)));
35   }
36   else if (cp <= 0xFFFF)
37   {
38      result.resize(3);
39      result[2] = static_cast<char>(0x80 | (0x3f & cp));
40      result[1] = 0x80 | static_cast<char>((0x3f & (cp >> 6)));
41      result[0] = 0xE0 | static_cast<char>((0xf & (cp >> 12)));
42   }
43   else if (cp <= 0x10FFFF)
44   {
45      result.resize(4);
46      result[3] = static_cast<char>(0x80 | (0x3f & cp));
47      result[2] = static_cast<char>(0x80 | (0x3f & (cp >> 6)));
48      result[1] = static_cast<char>(0x80 | (0x3f & (cp >> 12)));
49      result[0] = static_cast<char>(0xF0 | (0x7 & (cp >> 18)));
50   }
51
52   return result;
53}
54
55
56/// Returns true if ch is a control character (in range [0,32[).
57static inline bool
58isControlCharacter(char ch)
59{
60   return ch > 0 && ch <= 0x1F;
61}
62
63
64enum {
65   /// Constant that specify the size of the buffer that must be passed to uintToString.
66   uintToStringBufferSize = 3*sizeof(LargestUInt)+1
67};
68
69// Defines a char buffer for use with uintToString().
70typedef char UIntToStringBuffer[uintToStringBufferSize];
71
72
73/** Converts an unsigned integer to string.
74 * @param value Unsigned interger to convert to string
75 * @param current Input/Output string buffer.
76 *        Must have at least uintToStringBufferSize chars free.
77 */
78static inline void
79uintToString( LargestUInt value,
80              char *&current )
81{
82   *--current = 0;
83   do
84   {
85      *--current = char(value % 10) + '0';
86      value /= 10;
87   }
88   while ( value != 0 );
89}
90
91} // namespace Json {
92
93#endif // LIB_JSONCPP_JSON_TOOL_H_INCLUDED
94