Blame view

src/timestamp.cpp 2.89 KB
5251bf3a   Steven de Ridder   Initial commit. d...
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
  /* ****************************************************************************
   * Copyright 2019 Open Systems Development BV                                 *
   *                                                                            *
   * Permission is hereby granted, free of charge, to any person obtaining a    *
   * copy of this software and associated documentation files (the "Software"), *
   * to deal in the Software without restriction, including without limitation  *
   * the rights to use, copy, modify, merge, publish, distribute, sublicense,   *
   * and/or sell copies of the Software, and to permit persons to whom the      *
   * Software is furnished to do so, subject to the following conditions:       *
   *                                                                            *
   * The above copyright notice and this permission notice shall be included in *
   * all copies or substantial portions of the Software.                        *
   *                                                                            *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR *
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,   *
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL    *
   * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER *
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING    *
   * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER        *
   * DEALINGS IN THE SOFTWARE.                                                  *
   * ***************************************************************************/
  #include "timestamp.h"
  
  using namespace osdev::components;
  
  Timestamp::Timestamp()
      : m_msecsSinceEpoch(0)
      , m_seqNr(0)
  {
  }
  
  Timestamp::Timestamp(unsigned long long msecsSinceEpoch)
      : m_msecsSinceEpoch(msecsSinceEpoch)
      , m_seqNr(1)
  {
  }
  
  bool Timestamp::operator<(const Timestamp& rhs) const
  {
      if (m_msecsSinceEpoch < rhs.m_msecsSinceEpoch)
      {
          return true;
      }
  
      if (m_msecsSinceEpoch == rhs.m_msecsSinceEpoch)
      {
          return m_seqNr < rhs.m_seqNr;
      }
      return false;
  }
  
  Timestamp& Timestamp::operator++() // prefix
  {
      if (!valid())
      {
          return *this; // an invalid timestamp can only be made valid by assigning a valid timestamp to it.
      }
  
      if (m_seqNr < std::numeric_limits<decltype(m_seqNr)>::max())
      {
          ++m_seqNr;
      }
      else
      {
          // The idea is to never reach this point by choosing a large datatype.
          // Overflowing is not an option because then the < relation doesn't hold anymore.
          throw std::out_of_range("sequence number overflow");
      }
      return *this;
  }
  
  Timestamp Timestamp::operator++(int) // postfix
  {
      auto cpy(*this);
      ++(*this);
      return cpy;
  }
  
  QString Timestamp::toString() const
  {
      return QString("%1:%2").arg(m_msecsSinceEpoch).arg(m_seqNr);
  }