GRPC C++  1.39.1
string_ref.h
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18 
19 #ifndef GRPCPP_IMPL_CODEGEN_STRING_REF_H
20 #define GRPCPP_IMPL_CODEGEN_STRING_REF_H
21 
22 #include <string.h>
23 
24 #include <algorithm>
25 #include <iosfwd>
26 #include <iostream>
27 #include <iterator>
28 
30 
31 namespace grpc {
32 
41 class string_ref {
42  public:
44  typedef const char* const_iterator;
45  typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
46 
48  const static size_t npos;
49 
51  string_ref() : data_(nullptr), length_(0) {}
52  string_ref(const string_ref& other)
53  : data_(other.data_), length_(other.length_) {}
54  // NOLINTNEXTLINE(bugprone-unhandled-self-assignment)
56  data_ = rhs.data_;
57  length_ = rhs.length_;
58  return *this;
59  }
60 
61  /* NOLINTNEXTLINE(google-explicit-constructor) */
62  string_ref(const char* s) : data_(s), length_(strlen(s)) {}
63  string_ref(const char* s, size_t l) : data_(s), length_(l) {}
64  /* NOLINTNEXTLINE(google-explicit-constructor) */
65  string_ref(const std::string& s) : data_(s.data()), length_(s.length()) {}
66 
68  const_iterator begin() const { return data_; }
69  const_iterator end() const { return data_ + length_; }
70  const_iterator cbegin() const { return data_; }
71  const_iterator cend() const { return data_ + length_; }
73  return const_reverse_iterator(end());
74  }
76  return const_reverse_iterator(begin());
77  }
79  return const_reverse_iterator(end());
80  }
82  return const_reverse_iterator(begin());
83  }
84 
86  size_t size() const { return length_; }
87  size_t length() const { return length_; }
88  size_t max_size() const { return length_; }
89  bool empty() const { return length_ == 0; }
90 
92  const char* data() const { return data_; }
93 
95  int compare(string_ref x) const {
96  size_t min_size = length_ < x.length_ ? length_ : x.length_;
97  int r = memcmp(data_, x.data_, min_size);
98  if (r < 0) return -1;
99  if (r > 0) return 1;
100  if (length_ < x.length_) return -1;
101  if (length_ > x.length_) return 1;
102  return 0;
103  }
104 
105  bool starts_with(string_ref x) const {
106  return length_ >= x.length_ && (memcmp(data_, x.data_, x.length_) == 0);
107  }
108 
109  bool ends_with(string_ref x) const {
110  return length_ >= x.length_ &&
111  (memcmp(data_ + (length_ - x.length_), x.data_, x.length_) == 0);
112  }
113 
114  size_t find(string_ref s) const {
115  auto it = std::search(cbegin(), cend(), s.cbegin(), s.cend());
116  return it == cend() ? npos : std::distance(cbegin(), it);
117  }
118 
119  size_t find(char c) const {
120  auto it = std::find(cbegin(), cend(), c);
121  return it == cend() ? npos : std::distance(cbegin(), it);
122  }
123 
124  string_ref substr(size_t pos, size_t n = npos) const {
125  if (pos > length_) pos = length_;
126  if (n > (length_ - pos)) n = length_ - pos;
127  return string_ref(data_ + pos, n);
128  }
129 
130  private:
131  const char* data_;
132  size_t length_;
133 };
134 
136 inline bool operator==(string_ref x, string_ref y) { return x.compare(y) == 0; }
137 inline bool operator!=(string_ref x, string_ref y) { return x.compare(y) != 0; }
138 inline bool operator<(string_ref x, string_ref y) { return x.compare(y) < 0; }
139 inline bool operator<=(string_ref x, string_ref y) { return x.compare(y) <= 0; }
140 inline bool operator>(string_ref x, string_ref y) { return x.compare(y) > 0; }
141 inline bool operator>=(string_ref x, string_ref y) { return x.compare(y) >= 0; }
142 
143 inline std::ostream& operator<<(std::ostream& out, const string_ref& string) {
144  return out << std::string(string.begin(), string.end());
145 }
146 
147 } // namespace grpc
148 
149 #endif // GRPCPP_IMPL_CODEGEN_STRING_REF_H
This class is a non owning reference to a string.
Definition: string_ref.h:41
bool ends_with(string_ref x) const
Definition: string_ref.h:109
const_iterator cend() const
Definition: string_ref.h:71
string_ref(const char *s)
Definition: string_ref.h:62
const char * data() const
element access
Definition: string_ref.h:92
int compare(string_ref x) const
string operations
Definition: string_ref.h:95
size_t find(char c) const
Definition: string_ref.h:119
const_iterator begin() const
iterators
Definition: string_ref.h:68
std::reverse_iterator< const_iterator > const_reverse_iterator
Definition: string_ref.h:45
string_ref(const char *s, size_t l)
Definition: string_ref.h:63
string_ref & operator=(const string_ref &rhs)
Definition: string_ref.h:55
size_t max_size() const
Definition: string_ref.h:88
const_reverse_iterator rbegin() const
Definition: string_ref.h:72
bool empty() const
Definition: string_ref.h:89
string_ref()
construct/copy.
Definition: string_ref.h:51
size_t size() const
capacity
Definition: string_ref.h:86
const_iterator end() const
Definition: string_ref.h:69
const_reverse_iterator crend() const
Definition: string_ref.h:81
const_reverse_iterator rend() const
Definition: string_ref.h:75
string_ref(const string_ref &other)
Definition: string_ref.h:52
const char * const_iterator
types
Definition: string_ref.h:44
size_t find(string_ref s) const
Definition: string_ref.h:114
bool starts_with(string_ref x) const
Definition: string_ref.h:105
size_t length() const
Definition: string_ref.h:87
const_iterator cbegin() const
Definition: string_ref.h:70
string_ref substr(size_t pos, size_t n=npos) const
Definition: string_ref.h:124
const_reverse_iterator crbegin() const
Definition: string_ref.h:78
static const size_t npos
constants
Definition: string_ref.h:48
string_ref(const std::string &s)
Definition: string_ref.h:65
An Alarm posts the user-provided tag to its associated completion queue or invokes the user-provided ...
Definition: alarm.h:33
bool operator>=(string_ref x, string_ref y)
Definition: string_ref.h:141
std::ostream & operator<<(std::ostream &out, const string_ref &string)
Definition: string_ref.h:143
bool operator>(string_ref x, string_ref y)
Definition: string_ref.h:140
bool operator!=(string_ref x, string_ref y)
Definition: string_ref.h:137
bool operator<=(string_ref x, string_ref y)
Definition: string_ref.h:139
bool operator<(string_ref x, string_ref y)
Definition: string_ref.h:138
bool operator==(string_ref x, string_ref y)
Comparison operators.
Definition: string_ref.h:136