• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 
15 namespace Json {
16 
17 /// Converts a unicode code-point to UTF-8.
18 static inline std::string
codePointToUTF8(unsigned int cp)19 codePointToUTF8(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[).
57 static inline bool
isControlCharacter(char ch)58 isControlCharacter(char ch)
59 {
60    return ch > 0 && ch <= 0x1F;
61 }
62 
63 
64 enum {
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().
70 typedef 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  */
78 static inline void
uintToString(LargestUInt value,char * & current)79 uintToString( 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