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 
25 #include "ndn-cxx/encoding/buffer.hpp"
26 #include "ndn-cxx/util/span.hpp"
27 
28 #include <ostream>
29 #include <stdexcept>
30 #include <string>
31 #include <string_view>
32 
33 namespace ndn {
34 
35 class StringHelperError : public std::invalid_argument
36 {
37 public:
38  using std::invalid_argument::invalid_argument;
39 };
40 
50 void
51 printHex(std::ostream& os, uint64_t num, bool wantUpperCase = false);
52 
63 void
64 printHex(std::ostream& os, span<const uint8_t> buffer, bool wantUpperCase = true);
65 
77 class AsHex
78 {
79 public:
80  constexpr explicit
81  AsHex(uint64_t val) noexcept
82  : m_value(val)
83  {
84  }
85 
86 private:
87  friend std::ostream&
88  operator<<(std::ostream& os, const AsHex& hex)
89  {
90  printHex(os, hex.m_value, os.flags() & std::ostream::uppercase);
91  return os;
92  }
93 
94 private:
95  uint64_t m_value;
96 };
97 
107 [[nodiscard]] std::string
108 toHex(span<const uint8_t> buffer, bool wantUpperCase = true);
109 
116 std::shared_ptr<Buffer>
117 fromHex(std::string_view hexString);
118 
122 [[nodiscard]] constexpr char
123 toHexChar(unsigned int n, bool wantUpperCase = true) noexcept
124 {
125  return wantUpperCase ?
126  "0123456789ABCDEF"[n & 0xf] :
127  "0123456789abcdef"[n & 0xf];
128 }
129 
133 [[nodiscard]] constexpr int
134 fromHexChar(char c) noexcept
135 {
136  return (c >= '0' && c <= '9') ? int(c - '0') :
137  (c >= 'A' && c <= 'F') ? int(c - 'A' + 10) :
138  (c >= 'a' && c <= 'f') ? int(c - 'a' + 10) :
139  -1;
140 }
141 
159 [[nodiscard]] std::string
160 escape(std::string_view str);
161 
162 void
163 escape(std::ostream& os, std::string_view str);
164 
179 [[nodiscard]] std::string
180 unescape(std::string_view str);
181 
182 void
183 unescape(std::ostream& os, std::string_view str);
184 
185 } // namespace ndn
186 
187 #endif // NDN_CXX_UTIL_STRING_HELPER_HPP
ndn::AsHex
Helper class to convert a number to hexadecimal format, for use with stream insertion operators.
Definition: string-helper.hpp:78
ndn::AsHex::AsHex
constexpr AsHex(uint64_t val) noexcept
Definition: string-helper.hpp:81
ndn::AsHex::operator<<
friend std::ostream & operator<<(std::ostream &os, const AsHex &hex)
Definition: string-helper.hpp:88
ndn
Definition: data.cpp:25
ndn::printHex
void printHex(std::ostream &os, uint64_t num, bool wantUpperCase)
Output the hex representation of num to the output stream os.
Definition: string-helper.cpp:36
ndn::escape
std::string escape(std::string_view str)
Percent-encode a string.
Definition: string-helper.cpp:81
ndn::toHex
std::string toHex(span< const uint8_t > buffer, bool wantUpperCase)
Return a string containing the hex representation of the bytes in buffer.
Definition: string-helper.cpp:57
ndn::fromHex
shared_ptr< Buffer > fromHex(std::string_view hexString)
Convert a hex string to a raw byte buffer.
Definition: string-helper.cpp:65
ndn::fromHexChar
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.
Definition: string-helper.hpp:134
ndn::unescape
std::string unescape(std::string_view str)
Decode a percent-encoded string.
Definition: string-helper.cpp:109
ndn::toHexChar
constexpr char toHexChar(unsigned int n, bool wantUpperCase=true) noexcept
Convert (the least significant nibble of) n to the corresponding hex character.
Definition: string-helper.hpp:123