timestamp.cpp
2.89 KB
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
83
/* ****************************************************************************
* 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);
}