1 #ifndef MARISA_ALPHA_READER_H_ 2 #define MARISA_ALPHA_READER_H_ 3 4 #include <cstdio> 5 #include <iostream> 6 7 #include "base.h" 8 9 namespace marisa_alpha { 10 11 class Reader { 12 public: 13 Reader(); 14 explicit Reader(std::FILE *file); 15 explicit Reader(int fd); 16 explicit Reader(std::istream *stream); 17 ~Reader(); 18 19 void open(const char *filename, long offset = 0, int whence = SEEK_SET); 20 21 template <typename T> read(T * obj)22 void read(T *obj) { 23 MARISA_ALPHA_THROW_IF(obj == NULL, MARISA_ALPHA_PARAM_ERROR); 24 read_data(obj, sizeof(T)); 25 } 26 27 template <typename T> read(T * objs,std::size_t num_objs)28 void read(T *objs, std::size_t num_objs) { 29 MARISA_ALPHA_THROW_IF((objs == NULL) && (num_objs != 0), 30 MARISA_ALPHA_PARAM_ERROR); 31 MARISA_ALPHA_THROW_IF(num_objs > (MARISA_ALPHA_UINT32_MAX / sizeof(T)), 32 MARISA_ALPHA_SIZE_ERROR); 33 if (num_objs != 0) { 34 read_data(objs, sizeof(T) * num_objs); 35 } 36 } 37 is_open()38 bool is_open() const { 39 return (file_ != NULL) || (fd_ != -1) || (stream_ != NULL); 40 } 41 42 void clear(); 43 void swap(Reader *rhs); 44 45 private: 46 std::FILE *file_; 47 int fd_; 48 std::istream *stream_; 49 bool needs_fclose_; 50 51 void read_data(void *buf, std::size_t size); 52 53 // Disallows copy and assignment. 54 Reader(const Reader &); 55 Reader &operator=(const Reader &); 56 }; 57 58 } // namespace marisa_alpha 59 60 #endif // MARISA_ALPHA_READER_H_ 61