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
|
/* Copyright (C) Teemu Suutari */
#ifndef SUBBUFFER_HPP
#define SUBBUFFER_HPP
#include <cstddef>
#include <cstdint>
#include "Buffer.hpp"
#include "OverflowCheck.hpp"
namespace ancient::internal
{
// helpers to splice Buffer
template <typename T>
class GenericSubBuffer : public Buffer
{
public:
GenericSubBuffer(const GenericSubBuffer&)=delete;
GenericSubBuffer& operator=(const GenericSubBuffer&)=delete;
GenericSubBuffer(T &base,size_t start,size_t length) :
_base{base},
_start{start},
_length{length}
{
if (OverflowCheck::sum(start,length)>_base.size())
throw OutOfBoundsError();
}
~GenericSubBuffer() noexcept=default;
const uint8_t *data() const noexcept final
{
return _base.data()+_start;
}
uint8_t *data() final;
size_t size() const noexcept final
{
return _length;
}
bool isResizable() const noexcept final
{
return false;
}
// can only make the buffer smaller, can't run away from the current bounds
void adjust(size_t start,size_t length)
{
if (start<_start || OverflowCheck::sum(start,length)>_start+_length) throw OutOfBoundsError();
_start=start;
_length=length;
}
private:
T &_base;
size_t _start;
size_t _length;
};
typedef GenericSubBuffer<Buffer> SubBuffer;
typedef GenericSubBuffer<const Buffer> ConstSubBuffer;
}
#endif
|