1#ifndef MARISA_MAPPER_H_
2#define MARISA_MAPPER_H_
3
4#include <cstdio>
5
6#include "base.h"
7
8namespace marisa {
9
10class Mapper {
11 public:
12  Mapper();
13  Mapper(const void *ptr, std::size_t size);
14  ~Mapper();
15
16  void open(const char *filename, long offset = 0, int whence = SEEK_SET);
17
18  template <typename T>
19  void map(T *obj) {
20    MARISA_THROW_IF(obj == NULL, MARISA_PARAM_ERROR);
21    *obj = *static_cast<const T *>(map_data(sizeof(T)));
22  }
23
24  template <typename T>
25  void map(const T **objs, std::size_t num_objs) {
26    MARISA_THROW_IF((objs == NULL) && (num_objs != 0), MARISA_PARAM_ERROR);
27    MARISA_THROW_IF(num_objs > (MARISA_UINT32_MAX / sizeof(T)),
28        MARISA_SIZE_ERROR);
29    *objs = static_cast<const T *>(map_data(sizeof(T) * num_objs));
30  }
31
32  bool is_open() const {
33    return ptr_ != NULL;
34  }
35
36  void clear();
37  void swap(Mapper *rhs);
38
39 private:
40  const void *ptr_;
41  void *origin_;
42  std::size_t avail_;
43  std::size_t size_;
44#if defined _WIN32 || defined _WIN64
45  void *file_;
46  void *map_;
47#else  // defined _WIN32 || defined _WIN64
48  int fd_;
49#endif  // defined _WIN32 || defined _WIN64
50
51  void seek(long offset, int whence);
52
53  const void *map_data(std::size_t size);
54
55  // Disallows copy and assignment.
56  Mapper(const Mapper &);
57  Mapper &operator=(const Mapper &);
58};
59
60}  // namespace marisa
61
62#endif  // MARISA_MAPPER_H_
63