Libosmium  2.17.3
Fast and flexible C++ library for working with OpenStreetMap data
builder.hpp
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1 #ifndef OSMIUM_BUILDER_BUILDER_HPP
2 #define OSMIUM_BUILDER_BUILDER_HPP
3 
4 /*
5 
6 This file is part of Osmium (https://osmcode.org/libosmium).
7 
8 Copyright 2013-2022 Jochen Topf <jochen@topf.org> and others (see README).
9 
10 Boost Software License - Version 1.0 - August 17th, 2003
11 
12 Permission is hereby granted, free of charge, to any person or organization
13 obtaining a copy of the software and accompanying documentation covered by
14 this license (the "Software") to use, reproduce, display, distribute,
15 execute, and transmit the Software, and to prepare derivative works of the
16 Software, and to permit third-parties to whom the Software is furnished to
17 do so, all subject to the following:
18 
19 The copyright notices in the Software and this entire statement, including
20 the above license grant, this restriction and the following disclaimer,
21 must be included in all copies of the Software, in whole or in part, and
22 all derivative works of the Software, unless such copies or derivative
23 works are solely in the form of machine-executable object code generated by
24 a source language processor.
25 
26 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
27 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
28 FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
29 SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
30 FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
31 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
32 DEALINGS IN THE SOFTWARE.
33 
34 */
35 
36 #include <osmium/memory/buffer.hpp>
37 #include <osmium/memory/item.hpp>
39 
40 #include <algorithm>
41 #include <cassert>
42 #include <cstddef>
43 #include <cstdint>
44 #include <cstring>
45 
46 namespace osmium {
47 
51  namespace builder {
52 
57  class Builder {
58 
59  osmium::memory::Buffer& m_buffer;
61  std::size_t m_item_offset;
62 
63  protected:
64 
65  explicit Builder(osmium::memory::Buffer& buffer, Builder* parent, osmium::memory::item_size_type size) :
67  m_parent(parent),
68  m_item_offset(buffer.written() - buffer.committed()) {
70  assert(buffer.is_aligned());
71  if (m_parent) {
72  assert(m_buffer.builder_count() == 1 && "Only one sub-builder can be open at any time.");
74  } else {
75  assert(m_buffer.builder_count() == 0 && "Only one builder can be open at any time.");
76  }
77 #ifndef NDEBUG
78  m_buffer.increment_builder_count();
79 #endif
80  }
81 
82 #ifdef NDEBUG
83  ~Builder() noexcept = default;
84 #else
85  ~Builder() noexcept {
86  m_buffer.decrement_builder_count();
87  }
88 #endif
89 
90  unsigned char* item_pos() const noexcept {
91  return m_buffer.data() + m_buffer.committed() + m_item_offset;
92  }
93 
94  osmium::memory::Item& item() const noexcept {
95  return *reinterpret_cast<osmium::memory::Item*>(item_pos());
96  }
97 
98  unsigned char* reserve_space(std::size_t size) {
99  return m_buffer.reserve_space(size);
100  }
101 
115  void add_padding(bool self = false) {
116  // We know the padding is only a very small number, so it will
117  // always fit.
119  if (padding != osmium::memory::align_bytes) {
120  std::fill_n(reserve_space(padding), padding, 0);
121  if (self) {
122  add_size(padding);
123  } else if (m_parent) {
124  m_parent->add_size(padding);
125  assert(m_parent->size() % osmium::memory::align_bytes == 0);
126  }
127  }
128  }
129 
131  item().add_size(size);
132  if (m_parent) {
134  }
135  }
136 
137  uint32_t size() const noexcept {
138  return item().byte_size();
139  }
140 
145  template <typename T>
147  assert(m_buffer.is_aligned());
148  return reinterpret_cast<T*>(reserve_space(sizeof(T)));
149  }
150 
161  unsigned char* target = reserve_space(length);
162  std::copy_n(reinterpret_cast<const unsigned char*>(data), length, target);
163  return length;
164  }
165 
174  unsigned char* target = reserve_space(length + 1);
175  std::copy_n(reinterpret_cast<const unsigned char*>(data), length, target);
176  target[length] = '\0';
177  return length + 1;
178  }
179 
187  return append(str, static_cast<osmium::memory::item_size_type>(std::strlen(str) + 1));
188  }
189 
198  *reserve_space(1) = '\0';
199  return 1;
200  }
201 
202  public:
203 
204  Builder(const Builder&) = delete;
205  Builder(Builder&&) = delete;
206 
207  Builder& operator=(const Builder&) = delete;
208  Builder& operator=(Builder&&) = delete;
209 
211  osmium::memory::Buffer& buffer() noexcept {
212  return m_buffer;
213  }
214 
220  m_buffer.add_item(item);
222  }
223 
229  assert(item);
230  add_item(*item);
231  }
232 
233  }; // class Builder
234 
235  } // namespace builder
236 
237 } // namespace osmium
238 
239 #endif // OSMIUM_BUILDER_BUILDER_HPP
Definition: builder.hpp:57
osmium::memory::item_size_type append(const char *data, const osmium::memory::item_size_type length)
Definition: builder.hpp:160
uint32_t size() const noexcept
Definition: builder.hpp:137
osmium::memory::item_size_type append(const char *str)
Definition: builder.hpp:186
void add_padding(bool self=false)
Definition: builder.hpp:115
OSMIUM_DEPRECATED void add_item(const osmium::memory::Item *item)
Definition: builder.hpp:228
Builder(osmium::memory::Buffer &buffer, Builder *parent, osmium::memory::item_size_type size)
Definition: builder.hpp:65
void add_size(osmium::memory::item_size_type size)
Definition: builder.hpp:130
Builder(Builder &&)=delete
osmium::memory::Buffer & m_buffer
Definition: builder.hpp:59
unsigned char * reserve_space(std::size_t size)
Definition: builder.hpp:98
Builder & operator=(Builder &&)=delete
T * reserve_space_for()
Definition: builder.hpp:146
osmium::memory::Buffer & buffer() noexcept
Return the buffer this builder is using.
Definition: builder.hpp:211
osmium::memory::Item & item() const noexcept
Definition: builder.hpp:94
OSMIUM_DEPRECATED osmium::memory::item_size_type append_zero()
Definition: builder.hpp:197
Builder(const Builder &)=delete
std::size_t m_item_offset
Definition: builder.hpp:61
osmium::memory::item_size_type append_with_zero(const char *data, const osmium::memory::item_size_type length)
Definition: builder.hpp:173
void add_item(const osmium::memory::Item &item)
Definition: builder.hpp:219
unsigned char * item_pos() const noexcept
Definition: builder.hpp:90
Builder * m_parent
Definition: builder.hpp:60
Builder & operator=(const Builder &)=delete
~Builder() noexcept
Definition: builder.hpp:85
Definition: item.hpp:105
Item & add_size(const item_size_type size) noexcept
Definition: item.hpp:121
item_size_type byte_size() const noexcept
Definition: item.hpp:163
item_size_type padded_size() const
Definition: item.hpp:167
#define OSMIUM_DEPRECATED
Definition: compatibility.hpp:51
@ align_bytes
Definition: item.hpp:61
uint32_t item_size_type
Definition: item.hpp:57
Namespace for everything in the Osmium library.
Definition: assembler.hpp:53