Qpid Proton C++ 0.33.0
decoder.hpp
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1#ifndef PROTON_CODEC_DECODER_HPP
2#define PROTON_CODEC_DECODER_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 "../internal/data.hpp"
26#include "../internal/type_traits.hpp"
27#include "../types_fwd.hpp"
28#include "./common.hpp"
29
30#include <proton/type_compat.h>
31
32#include <utility>
33
36
37namespace proton {
38
39class annotation_key;
40class message_id;
41class scalar;
42class value;
43
44namespace internal {
45class value_base;
46}
47
48namespace codec {
49
56class decoder : public internal::data {
57 public:
61 explicit decoder(const data& d, bool exact=false) : data(d), exact_(exact) {}
62
65 PN_CPP_EXTERN explicit decoder(const internal::value_base&, bool exact=false);
66
69 PN_CPP_EXTERN void decode(const char* buffer, size_t size);
70
73 PN_CPP_EXTERN void decode(const std::string&);
74
76 PN_CPP_EXTERN bool more();
77
83 PN_CPP_EXTERN type_id next_type();
84
91 PN_CPP_EXTERN decoder& operator>>(bool&);
92 PN_CPP_EXTERN decoder& operator>>(uint8_t&);
93 PN_CPP_EXTERN decoder& operator>>(int8_t&);
94 PN_CPP_EXTERN decoder& operator>>(uint16_t&);
95 PN_CPP_EXTERN decoder& operator>>(int16_t&);
96 PN_CPP_EXTERN decoder& operator>>(uint32_t&);
97 PN_CPP_EXTERN decoder& operator>>(int32_t&);
98 PN_CPP_EXTERN decoder& operator>>(wchar_t&);
99 PN_CPP_EXTERN decoder& operator>>(uint64_t&);
100 PN_CPP_EXTERN decoder& operator>>(int64_t&);
101 PN_CPP_EXTERN decoder& operator>>(timestamp&);
102 PN_CPP_EXTERN decoder& operator>>(float&);
103 PN_CPP_EXTERN decoder& operator>>(double&);
104 PN_CPP_EXTERN decoder& operator>>(decimal32&);
105 PN_CPP_EXTERN decoder& operator>>(decimal64&);
106 PN_CPP_EXTERN decoder& operator>>(decimal128&);
107 PN_CPP_EXTERN decoder& operator>>(uuid&);
108 PN_CPP_EXTERN decoder& operator>>(std::string&);
109 PN_CPP_EXTERN decoder& operator>>(symbol&);
110 PN_CPP_EXTERN decoder& operator>>(binary&);
111 PN_CPP_EXTERN decoder& operator>>(message_id&);
112 PN_CPP_EXTERN decoder& operator>>(annotation_key&);
113 PN_CPP_EXTERN decoder& operator>>(scalar&);
114 PN_CPP_EXTERN decoder& operator>>(internal::value_base&);
115 PN_CPP_EXTERN decoder& operator>>(null&);
116#if PN_CPP_HAS_NULLPTR
117 PN_CPP_EXTERN decoder& operator>>(decltype(nullptr)&);
118#endif
120
125 PN_CPP_EXTERN decoder& operator>>(start&);
126
129 PN_CPP_EXTERN decoder& operator>>(const finish&);
130
132 template <class T> struct sequence_ref { T& ref; sequence_ref(T& r) : ref(r) {} };
133 template <class T> struct associative_ref { T& ref; associative_ref(T& r) : ref(r) {} };
134 template <class T> struct pair_sequence_ref { T& ref; pair_sequence_ref(T& r) : ref(r) {} };
135
136 template <class T> static sequence_ref<T> sequence(T& x) { return sequence_ref<T>(x); }
137 template <class T> static associative_ref<T> associative(T& x) { return associative_ref<T>(x); }
138 template <class T> static pair_sequence_ref<T> pair_sequence(T& x) { return pair_sequence_ref<T>(x); }
140
144 template <class T> decoder& operator>>(sequence_ref<T> r) {
145 start s;
146 *this >> s;
147 if (s.is_described) next();
148 r.ref.resize(s.size);
149 for (typename T::iterator i = r.ref.begin(); i != r.ref.end(); ++i)
150 *this >> *i;
151 return *this;
152 }
153
155 template <class T> decoder& operator>>(associative_ref<T> r) {
156 using namespace internal;
157 start s;
158 *this >> s;
159 assert_type_equal(MAP, s.type);
160 r.ref.clear();
161 for (size_t i = 0; i < s.size/2; ++i) {
162 typename remove_const<typename T::key_type>::type k;
163 typename remove_const<typename T::mapped_type>::type v;
164 *this >> k >> v;
165 r.ref[k] = v;
166 }
167 return *this;
168 }
169
172 template <class T> decoder& operator>>(pair_sequence_ref<T> r) {
173 using namespace internal;
174 start s;
175 *this >> s;
176 assert_type_equal(MAP, s.type);
177 r.ref.clear();
178 for (size_t i = 0; i < s.size/2; ++i) {
179 typedef typename T::value_type value_type;
180 typename remove_const<typename value_type::first_type>::type k;
181 typename remove_const<typename value_type::second_type>::type v;
182 *this >> k >> v;
183 r.ref.push_back(value_type(k, v));
184 }
185 return *this;
186 }
187
188 private:
189 type_id pre_get();
190 template <class T, class U> decoder& extract(T& x, U (*get)(pn_data_t*));
191 bool exact_;
192
193 friend class message;
194};
195
198template<class T> T get(decoder& d) {
199 assert_type_equal(internal::type_id_of<T>::value, d.next_type());
200 T x;
201 d >> x;
202 return x;
203}
205
208template <class T> typename internal::enable_if<internal::is_unknown_integer<T>::value, decoder&>::type
210 using namespace internal;
211 typename integer_type<sizeof(T), is_signed<T>::value>::type v;
212 d >> v; // Extract as a known integer type
213 i = v; // C++ conversion to the target type.
214 return d;
215}
216
217} // codec
218} // proton
219
220#endif // PROTON_CODEC_DECODER_HPP
A key for use with AMQP annotation maps.
Definition: annotation_key.hpp:38
Arbitrary binary data.
Definition: binary.hpp:40
Unsettled API - A stream-like decoder from AMQP bytes to C++ values.
Definition: decoder.hpp:56
decoder & operator>>(sequence_ref< T > r)
Extract any AMQP sequence (ARRAY, LIST or MAP) to a C++ sequence container of T if the elements types...
Definition: decoder.hpp:144
void decode(const char *buffer, size_t size)
Decode AMQP data from a buffer and add it to the end of the decoders stream.
decoder & operator>>(const finish &)
Finish decoding a container type, and move on to the next value in the stream.
decoder & operator>>(pair_sequence_ref< T > r)
Extract an AMQP MAP to a C++ push_back sequence of pairs preserving encoded order.
Definition: decoder.hpp:172
decoder & operator>>(start &)
Start decoding a container type, such as an ARRAY, LIST or MAP.
void decode(const std::string &)
Decode AMQP data from a std::string and add it to the end of the decoders stream.
bool more()
Return true if there are more value to extract at the current level.
decoder & operator>>(associative_ref< T > r)
Extract an AMQP MAP to a C++ associative container.
Definition: decoder.hpp:155
decoder(const data &d, bool exact=false)
Wrap a Proton C data object.
Definition: decoder.hpp:61
decoder(const internal::value_base &, bool exact=false)
Attach decoder to a proton::value.
type_id next_type()
Get the type of the next value that will be read by operator>>.
A 128-bit decimal floating-point value.
Definition: decimal.hpp:52
A 32-bit decimal floating-point value.
Definition: decimal.hpp:46
A 64-bit decimal floating-point value.
Definition: decimal.hpp:49
An AMQP message ID.
Definition: message_id.hpp:47
An AMQP message.
Definition: message.hpp:50
The type of the AMQP null value.
Definition: null.hpp:39
A holder for an instance of any scalar AMQP type.
Definition: scalar.hpp:37
A string that represents the AMQP symbol type.
Definition: symbol.hpp:35
A 64-bit timestamp in milliseconds since the Unix epoch.
Definition: timestamp.hpp:35
A 16-byte universally unique identifier.
Definition: uuid.hpp:37
Unsettled API - Shared codec functions.
internal::enable_if< internal::is_unknown_integer< T >::value, decoder & >::type operator>>(decoder &d, T &i)
operator>> for integer types that are not covered by the standard overrides.
Definition: decoder.hpp:209
Unsettled API - Finish inserting or extracting a complex type.
Definition: common.hpp:57
Unsettled API - Start encoding a complex type.
Definition: common.hpp:34
The main Proton namespace.
Definition: annotation_key.hpp:33
T get(const scalar &s)
Get a contained value of type T.
Definition: scalar.hpp:60
type_id
An identifier for AMQP types.
Definition: type_id.hpp:37
@ MAP
A sequence of key-value pairs.
Definition: type_id.hpp:62
void assert_type_equal(type_id want, type_id got)
Throw a conversion_error if want != got with a message including the names of the types.