Qpid Proton C++  0.17.0
scalar_base.hpp
1 #ifndef PROTON_SCALAR_BASE_HPP
2 #define PROTON_SCALAR_BASE_HPP
3 
4 /*
5  *
6  * Licensed to the Apache Software Foundation (ASF) under one
7  * or more contributor license agreements. See the NOTICE file
8  * distributed with this work for additional information
9  * regarding copyright ownership. The ASF licenses this file
10  * to you under the Apache License, Version 2.0 (the
11  * "License"); you may not use this file except in compliance
12  * with the License. You may obtain a copy of the License at
13  *
14  * http://www.apache.org/licenses/LICENSE-2.0
15  *
16  * Unless required by applicable law or agreed to in writing,
17  * software distributed under the License is distributed on an
18  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
19  * KIND, either express or implied. See the License for the
20  * specific language governing permissions and limitations
21  * under the License.
22  *
23  */
24 
25 #include "./binary.hpp"
26 #include "./decimal.hpp"
27 #include "./error.hpp"
28 #include "./internal/comparable.hpp"
29 #include "./internal/export.hpp"
30 #include "./internal/type_traits.hpp"
31 #include "./symbol.hpp"
32 #include "./timestamp.hpp"
33 #include "./type_id.hpp"
34 #include "./types_fwd.hpp"
35 #include "./uuid.hpp"
36 
37 #include <proton/type_compat.h>
38 
39 #include <iosfwd>
40 #include <string>
41 #include <typeinfo>
42 
43 namespace proton {
44 
45 class scalar_base;
46 
47 namespace codec {
48 class decoder;
49 class encoder;
50 }
51 
52 namespace internal {
53 template<class T> T get(const scalar_base& s);
54 }
55 
57 class scalar_base : private internal::comparable<scalar_base> {
58  public:
60  PN_CPP_EXTERN type_id type() const;
61 
63  PN_CPP_EXTERN bool empty() const;
64 
66  friend PN_CPP_EXTERN bool operator<(const scalar_base& x, const scalar_base& y);
68  friend PN_CPP_EXTERN bool operator==(const scalar_base& x, const scalar_base& y);
70  friend PN_CPP_EXTERN std::ostream& operator<<(std::ostream& o, const scalar_base& x);
71 
72  protected:
73  PN_CPP_EXTERN scalar_base(const pn_atom_t& a);
74  PN_CPP_EXTERN scalar_base();
75  PN_CPP_EXTERN scalar_base(const scalar_base&);
76  PN_CPP_EXTERN scalar_base& operator=(const scalar_base&);
77 
78  PN_CPP_EXTERN void put_(bool);
79  PN_CPP_EXTERN void put_(uint8_t);
80  PN_CPP_EXTERN void put_(int8_t);
81  PN_CPP_EXTERN void put_(uint16_t);
82  PN_CPP_EXTERN void put_(int16_t);
83  PN_CPP_EXTERN void put_(uint32_t);
84  PN_CPP_EXTERN void put_(int32_t);
85  PN_CPP_EXTERN void put_(uint64_t);
86  PN_CPP_EXTERN void put_(int64_t);
87  PN_CPP_EXTERN void put_(wchar_t);
88  PN_CPP_EXTERN void put_(float);
89  PN_CPP_EXTERN void put_(double);
90  PN_CPP_EXTERN void put_(timestamp);
91  PN_CPP_EXTERN void put_(const decimal32&);
92  PN_CPP_EXTERN void put_(const decimal64&);
93  PN_CPP_EXTERN void put_(const decimal128&);
94  PN_CPP_EXTERN void put_(const uuid&);
95  PN_CPP_EXTERN void put_(const std::string&);
96  PN_CPP_EXTERN void put_(const symbol&);
97  PN_CPP_EXTERN void put_(const binary&);
98  PN_CPP_EXTERN void put_(const char* s);
99  PN_CPP_EXTERN void put_(const null&);
100 
101  template<class T> void put(const T& x) { putter<T>::put(*this, x); }
102 
103  private:
104  PN_CPP_EXTERN void get_(bool&) const;
105  PN_CPP_EXTERN void get_(uint8_t&) const;
106  PN_CPP_EXTERN void get_(int8_t&) const;
107  PN_CPP_EXTERN void get_(uint16_t&) const;
108  PN_CPP_EXTERN void get_(int16_t&) const;
109  PN_CPP_EXTERN void get_(uint32_t&) const;
110  PN_CPP_EXTERN void get_(int32_t&) const;
111  PN_CPP_EXTERN void get_(uint64_t&) const;
112  PN_CPP_EXTERN void get_(int64_t&) const;
113  PN_CPP_EXTERN void get_(wchar_t&) const;
114  PN_CPP_EXTERN void get_(float&) const;
115  PN_CPP_EXTERN void get_(double&) const;
116  PN_CPP_EXTERN void get_(timestamp&) const;
117  PN_CPP_EXTERN void get_(decimal32&) const;
118  PN_CPP_EXTERN void get_(decimal64&) const;
119  PN_CPP_EXTERN void get_(decimal128&) const;
120  PN_CPP_EXTERN void get_(uuid&) const;
121  PN_CPP_EXTERN void get_(std::string&) const;
122  PN_CPP_EXTERN void get_(symbol&) const;
123  PN_CPP_EXTERN void get_(binary&) const;
124  PN_CPP_EXTERN void get_(null&) const;
125 
126  // use template structs, functions cannot be partially specialized.
127  template <class T, class Enable=void> struct putter {
128  static void put(scalar_base& s, const T& x) { s.put_(x); }
129  };
130  template <class T>
131  struct putter<T, typename internal::enable_if<internal::is_unknown_integer<T>::value>::type> {
132  static void put(scalar_base& s, const T& x) {
133  s.put_(static_cast<typename internal::known_integer<T>::type>(x));
134  }
135  };
136  template <class T, class Enable=void>
137  struct getter {
138  static T get(const scalar_base& s) { T x; s.get_(x); return x; }
139  };
140  template <class T>
141  struct getter<T, typename internal::enable_if<internal::is_unknown_integer<T>::value>::type> {
142  static T get(const scalar_base& s) {
143  typename internal::known_integer<T>::type x; s.get_(x); return x;
144  }
145  };
146 
147  void ok(pn_type_t) const;
148  void set(const pn_atom_t&);
149  void set(const binary& x, pn_type_t t);
150 
151  pn_atom_t atom_;
152  binary bytes_; // Hold binary data.
153 
155  friend class message;
156  friend class codec::encoder;
157  friend class codec::decoder;
158  template<class T> friend T internal::get(const scalar_base& s);
160 };
161 
162 namespace internal {
163 
164 template<class T> T get(const scalar_base& s) {
165  return scalar_base::getter<T>::get(s);
166 }
167 
168 template <class R, class F> R visit(const scalar_base& s, F f) {
169  switch(s.type()) {
170  case BOOLEAN: return f(internal::get<bool>(s));
171  case UBYTE: return f(internal::get<uint8_t>(s));
172  case BYTE: return f(internal::get<int8_t>(s));
173  case USHORT: return f(internal::get<uint16_t>(s));
174  case SHORT: return f(internal::get<int16_t>(s));
175  case UINT: return f(internal::get<uint32_t>(s));
176  case INT: return f(internal::get<int32_t>(s));
177  case CHAR: return f(internal::get<wchar_t>(s));
178  case ULONG: return f(internal::get<uint64_t>(s));
179  case LONG: return f(internal::get<int64_t>(s));
180  case TIMESTAMP: return f(internal::get<timestamp>(s));
181  case FLOAT: return f(internal::get<float>(s));
182  case DOUBLE: return f(internal::get<double>(s));
183  case DECIMAL32: return f(internal::get<decimal32>(s));
184  case DECIMAL64: return f(internal::get<decimal64>(s));
185  case DECIMAL128: return f(internal::get<decimal128>(s));
186  case UUID: return f(internal::get<uuid>(s));
187  case BINARY: return f(internal::get<binary>(s));
188  case STRING: return f(internal::get<std::string>(s));
189  case SYMBOL: return f(internal::get<symbol>(s));
190  default: throw conversion_error("invalid scalar type "+type_name(s.type()));
191  }
192 }
193 
194 PN_CPP_EXTERN conversion_error make_coercion_error(const char* cpp_type, type_id amqp_type);
195 
196 template<class T> struct coerce_op {
197  template <class U>
198  typename enable_if<is_convertible<U, T>::value, T>::type operator()(const U& x) {
199  return static_cast<T>(x);
200  }
201  template <class U>
202  typename enable_if<!is_convertible<U, T>::value, T>::type operator()(const U&) {
203  throw make_coercion_error(typeid(T).name(), type_id_of<U>::value);
204  }
205 };
206 
207 template <class T> T coerce(const scalar_base& s) { return visit<T>(s, coerce_op<T>()); }
208 } // namespace internal
209 
211 PN_CPP_EXTERN std::string to_string(const scalar_base& x);
212 
213 } // proton
214 
215 #endif // PROTON_SCALAR_BASE_HPP
16-byte UUID.
Definition: type_id.hpp:56
An AMQP message.
Definition: message.hpp:47
Experimental - Stream-like encoder from C++ values to AMQP bytes.
Definition: encoder.hpp:47
encoder & operator<<(encoder &e, const std::deque< T, A > &x)
std::deque<T> for most T is encoded as an amqp::ARRAY (same type elements)
Definition: deque.hpp:34
Variable-length utf8-encoded string.
Definition: type_id.hpp:58
A 16-byte universally unique identifier.
Definition: uuid.hpp:34
std::string type_name(type_id)
Get the name of the AMQP type.
An error converting between AMQP and C++ data.
Definition: error.hpp:51
64-bit decimal floating point.
Definition: decimal.hpp:49
Variable-length encoded string.
Definition: type_id.hpp:59
Base class for scalar types.
Definition: scalar_base.hpp:57
Signed 64-bit milliseconds since the epoch.
Definition: type_id.hpp:50
Variable-length sequence of bytes.
Definition: type_id.hpp:57
64-bit binary floating point.
Definition: type_id.hpp:52
A std::string that represents the AMQP symbol type.
Definition: symbol.hpp:32
Type-identifiers for AMQP types.
32-bit decimal floating point.
Definition: type_id.hpp:53
Arbitrary binary data.
Definition: binary.hpp:37
128-bit decimal floating point.
Definition: decimal.hpp:52
Signed 8-bit integer.
Definition: type_id.hpp:42
Unsigned 8-bit integer.
Definition: type_id.hpp:41
Signed 64-bit integer.
Definition: type_id.hpp:49
std::string to_string(const scalar_base &x)
Return a readable string representation of x for display purposes.
Boolean true or false.
Definition: type_id.hpp:40
type_id
An identifier for AMQP types.
Definition: type_id.hpp:38
32-bit decimal floating point.
Definition: decimal.hpp:46
32-bit unicode character.
Definition: type_id.hpp:47
Forward declarations for all the C++ types used by Proton to represent AMQP types.
A 64-bit timestamp in milliseconds since the Unix epoch.
Definition: timestamp.hpp:32
Unsigned 32-bit integer.
Definition: type_id.hpp:45
Unsigned 64-bit integer.
Definition: type_id.hpp:48
Signed 16-bit integer.
Definition: type_id.hpp:44
Signed 32-bit integer.
Definition: type_id.hpp:46
Unsigned 16-bit integer.
Definition: type_id.hpp:43
64-bit decimal floating point.
Definition: type_id.hpp:54
type_id type() const
AMQP type of data stored in the scalar.
128-bit decimal floating point.
Definition: type_id.hpp:55
The main Proton namespace.
Definition: annotation_key.hpp:30
Experimental - Stream-like decoder from AMQP bytes to C++ values.
Definition: decoder.hpp:53
32-bit binary floating point.
Definition: type_id.hpp:51