headers/os/package/hpkg/DataReader.h

   1 /*
   2  * Copyright 2009-2014, Haiku, Inc.
   3  * Distributed under the terms of the MIT License.
   4  */
   5 #ifndef _PACKAGE__HPKG__DATA_READER_H_
   6 #define _PACKAGE__HPKG__DATA_READER_H_
   7
   8
   9 #include <SupportDefs.h>
  10
  11
  12 class BDataIO;
  13
  14
  15 namespace BPackageKit {
  16
  17 namespace BHPKG {
  18
  19
  20 class BDataReader {
  21 public:
  22         virtual                                         ~BDataReader();
  23
  24         virtual status_t                        ReadData(off_t offset, void* buffer,
  25                                                                         size_t size) = 0;
  26 };
  27
  28
  29 class BAbstractBufferedDataReader : public BDataReader {
  30 public:
  31         virtual                                         ~BAbstractBufferedDataReader();
  32
  33         virtual status_t                        ReadData(off_t offset, void* buffer,
  34                                                                         size_t size);
  35         virtual status_t                        ReadDataToOutput(off_t offset, size_t size,
  36                                                                         BDataIO* output) = 0;
  37 };
  38
  39
  40 class BFDDataReader : public BDataReader {
  41 public:
  42                                                                 BFDDataReader(int fd);
  43
  44                         void                            SetFD(int fd);
  45
  46         virtual status_t                        ReadData(off_t offset, void* buffer,
  47                                                                         size_t size);
  48
  49 private:
  50                         int                                     fFD;
  51 };
  52
  53
  54 class BAttributeDataReader : public BDataReader {
  55 public:
  56                                                                 BAttributeDataReader(int fd,
  57                                                                         const char* attribute, uint32 type);
  58
  59         virtual status_t                        ReadData(off_t offset, void* buffer,
  60                                                                         size_t size);
  61
  62 private:
  63                         int                                     fFD;
  64                         uint32                          fType;
  65                         const char*                     fAttribute;
  66 };
  67
  68
  69 class BBufferDataReader : public BAbstractBufferedDataReader {
  70 public:
  71                                                                 BBufferDataReader(const void* data, size_t size);
  72
  73         virtual status_t                        ReadData(off_t offset, void* buffer,
  74                                                                         size_t size);
  75         virtual status_t                        ReadDataToOutput(off_t offset, size_t size,
  76                                                                         BDataIO* output);
  77
  78 private:
  79                         const void*                     fData;
  80                         size_t                          fSize;
  81 };
  82
  83
  84 }       // namespace BHPKG
  85
  86 }       // namespace BPackageKit
  87
  88
  89 #endif  // _PACKAGE__HPKG__DATA_READER_H_