-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathdatatype.cpp
More file actions
106 lines (99 loc) · 2.32 KB
/
Copy pathdatatype.cpp
File metadata and controls
106 lines (99 loc) · 2.32 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
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
#include <iostream>
#include <memory>
#include <cstring>
#include <cstdlib>
#include <cstdint>
#include <cassert>
#include <climits>
using namespace std;
void test_char2int()
{
uint8_t a[] = {1, 1, 0, 0, 2, 1, 0, 0, 3, 1, 0, 0, 4, 1, 0, 0};
uint32_t* iptr = (uint32_t*) malloc(sizeof(a));
memcpy(iptr, a, sizeof(a));
for(int i = 0; i < sizeof(a)/sizeof(uint32_t); ++i)
{
std::cout << iptr[i]<< " ";
}
std::cout << endl;
}
//float还是double在存储方式上都是遵从IEEE的规范的，
//float遵从的是IEEE R32.24 ,而double 遵从的是R64.53
// float = |one bit for sign| 8bit for exponent| 23bit for mantissa
// double = |1| 11 |52|
void test_char2float()
{
uint8_t a[] = { 0x01, 0x00, 0x00, 0x00,
0x01, 0x00, 0x00, 0x80,
0x00, 0x00, 0x80, 0x40,
0x00, 0x00, 0x80, 0x41,
0x80, 0x00, 0x00, 0x00,
};
float* fptr = (float*) malloc(sizeof(a));
memcpy(fptr, a, sizeof(a));
for(int i = 0; i < sizeof(a)/sizeof(float); ++i)
{
std::cout << fptr[i]<< " ";
}
std::cout << endl;
assert(fptr[0] + fptr[1] == 0.0);
assert(fptr[0]*128 - fptr[2] < 1e-6);
}
void test_memset()
{
uint8_t a[128] = {};
memset(a, 0, 128);
for(int i = 0; i < 128; ++i)
a[i] = i;
for(int i = 0; i < 128; ++i)
std::cout << i << " " << a[i] << std::endl;
std::cout << std::endl;
}
void test_sizeof()
{
assert(sizeof(uint8_t) == 1);
assert(sizeof(int8_t) == 1);
assert(sizeof(uint16_t) == 2);
assert(sizeof(int16_t) == 2);
assert(sizeof(int) == 4);
assert(sizeof(long) == 4);
assert(sizeof(long long) == 8);
assert(sizeof(float) == 4);
assert(sizeof(double) == 8);
assert(INT_MAX == 2147483647);
std::cout << MB_LEN_MAX << std::endl;
std::cout << UCHAR_MAX << std::endl;
std::cout << USHRT_MAX << std::endl;
std::cout << UINT_MAX << std::endl;
std::cout << LONG_MAX << std::endl;
std::cout << LLONG_MAX << std::endl;
}
std::string LOG_hello()
{
return "## hello";
}
std::string LOG_bye()
{
return "## bye";
}
// #，#@，##
#define INFO(value) \
std::cout <<__DATE__ << " " << __TIME__ <<" "; \
std::cout <<__FILE__ <<":" << __LINE__<< ":" \
<< LOG_##value() << std::endl;
#define LOG(value) \
std::cout << #value << std::endl;
void test_macro()
{
INFO(hello);
INFO(bye);
LOG(log_hello);
LOG(log_bye);
}
int main(int argc, char const *argv[])
{
//test_char2int();
//test_char2float();
test_macro();
return 0;
}