string-helper.hpp
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21 
22 #ifndef NDN_CXX_UTIL_STRING_HELPER_HPP
23 #define NDN_CXX_UTIL_STRING_HELPER_HPP
24 
26 #include "ndn-cxx/util/span.hpp"
27 
28 namespace ndn {
29 
30 class StringHelperError : public std::invalid_argument
31 {
32 public:
33  using std::invalid_argument::invalid_argument;
34 };
35 
45 void
46 printHex(std::ostream& os, uint64_t num, bool wantUpperCase = false);
47 
55 void
56 printHex(std::ostream& os, span<const uint8_t> buffer, bool wantUpperCase = true);
57 
77 inline void
78 printHex(std::ostream& os, const uint8_t* buffer, size_t length, bool wantUpperCase = true)
79 {
80  printHex(os, {buffer, length}, wantUpperCase);
81 }
82 
94 class AsHex
95 {
96 public:
97  constexpr explicit
98  AsHex(uint64_t val) noexcept
99  : m_value(val)
100  {
101  }
102 
103 private:
104  friend std::ostream&
105  operator<<(std::ostream& os, const AsHex& hex)
106  {
107  printHex(os, hex.m_value, os.flags() & std::ostream::uppercase);
108  return os;
109  }
110 
111 private:
112  uint64_t m_value;
113 };
114 
121 NDN_CXX_NODISCARD std::string
122 toHex(span<const uint8_t> buffer, bool wantUpperCase = true);
123 
142 NDN_CXX_NODISCARD inline std::string
143 toHex(const uint8_t* buffer, size_t length, bool wantUpperCase = true)
144 {
145  return toHex({buffer, length}, wantUpperCase);
146 }
147 
154 shared_ptr<Buffer>
155 fromHex(const std::string& hexString);
156 
160 NDN_CXX_NODISCARD constexpr char
161 toHexChar(unsigned int n, bool wantUpperCase = true) noexcept
162 {
163  return wantUpperCase ?
164  "0123456789ABCDEF"[n & 0xf] :
165  "0123456789abcdef"[n & 0xf];
166 }
167 
171 NDN_CXX_NODISCARD constexpr int
172 fromHexChar(char c) noexcept
173 {
174  return (c >= '0' && c <= '9') ? int(c - '0') :
175  (c >= 'A' && c <= 'F') ? int(c - 'A' + 10) :
176  (c >= 'a' && c <= 'f') ? int(c - 'a' + 10) :
177  -1;
178 }
179 
196 NDN_CXX_NODISCARD std::string
197 escape(const std::string& str);
198 
199 void
200 escape(std::ostream& os, const char* str, size_t len);
201 
215 NDN_CXX_NODISCARD std::string
216 unescape(const std::string& str);
217 
218 void
219 unescape(std::ostream& os, const char* str, size_t len);
220 
221 } // namespace ndn
222 
223 #endif // NDN_CXX_UTIL_STRING_HELPER_HPP
#define NDN_CXX_NODISCARD
Definition: backports.hpp:68
Helper class to convert a number to hexadecimal format, for use with stream insertion operators.
constexpr AsHex(uint64_t val) noexcept
friend std::ostream & operator<<(std::ostream &os, const AsHex &hex)
Definition: data.cpp:25
void printHex(std::ostream &os, uint64_t num, bool wantUpperCase)
Output the hex representation of num to the output stream os.
shared_ptr< Buffer > fromHex(const std::string &hexString)
Convert the hex string to buffer.
std::string toHex(span< const uint8_t > buffer, bool wantUpperCase)
Return a string containing the hex representation of the bytes in buffer.
std::string unescape(const std::string &str)
Decode a percent-encoded string.
constexpr int fromHexChar(char c) noexcept
Convert the hex character c to an integer in [0, 15], or -1 if it's not a hex character.
constexpr char toHexChar(unsigned int n, bool wantUpperCase=true) noexcept
Convert (the least significant nibble of) n to the corresponding hex character.
std::string escape(const std::string &str)
Percent-encode a string.