Disk ARchive  2.7.14
Full featured and portable backup and archiving tool
int_tools.hpp
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2 // dar - disk archive - a backup/restoration program
3 // Copyright (C) 2002-2024 Denis Corbin
4 //
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9 //
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21 
26 
27 #ifndef INT_TOOLS_HPP
28 #define INT_TOOLS_HPP
29 
30 #include "../my_config.h"
31 
32 #include "integers.hpp"
33 
34 namespace libdar
35 {
36 
39 
40  using int_tools_bitfield = unsigned char[8];
41 
42  extern void int_tools_swap_bytes(unsigned char &a, unsigned char &b);
43  extern void int_tools_swap_bytes(unsigned char *a, U_I size);
44  extern void int_tools_expand_byte(unsigned char a, int_tools_bitfield &bit);
45  extern void int_tools_contract_byte(const int_tools_bitfield &b, unsigned char & a);
46 
47  // integer (agregates) manipulations
48  // argument must be a regular interger (a bit field).
49  template <class T> extern T int_tools_rotate_right_one_bit(T v)
50  {
51  bool retenue = (v & 1) != 0;
52 
53  v >>= 1;
54  if(retenue)
55  v |= T(1) << (sizeof(v)*8 - 1);
56 
57  return v;
58  }
59 
60  template <class T> extern T int_tools_maxof_aggregate(T unused) { unused = 0; unused = ~unused; unused = unused > 0 ? unused : ~int_tools_rotate_right_one_bit(T(1)); return unused; }
61 
62  template <class B> static B int_tools_higher_power_of_2(B val)
63  {
64  B i = 0;
65 
66  while((val >> i) > 1)
67  i++;
68 
69  return i;
70  }
71 
73 
74 }
75 
76 #endif
are defined here basic integer types that tend to be portable
libdar namespace encapsulate all libdar symbols
Definition: archive.hpp:47