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
|
#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#ifndef CHANGE_SRC_ACTUAL_FUNCTION_H_
#define CHANGE_SRC_ACTUAL_FUNCTION_H_
#include <dlfcn.h>
#include <sys/mman.h>
#include <memory>
#include <cstring>
namespace {
template <class Result, typename... Arguments>
std::function<Result(Arguments...)> get_actual_function(
const std::string& symbol_name) {
Result (*real_function)(Arguments...) = nullptr;
const void* symbol_address = dlsym(RTLD_NEXT, symbol_name.c_str());
std::memcpy(&real_function, &symbol_address, sizeof(symbol_address));
return std::function<Result(Arguments...)>(real_function);
}
}
namespace actual {
static auto write = get_actual_function<
ssize_t,
int, const void*, size_t
>("write");
static auto rename = get_actual_function<
int,
const char*, const char*
>("rename");
static auto rmdir = get_actual_function<
int,
const char*
>("rmdir");
static auto unlink = get_actual_function<
int,
const char*
>("unlink");
static auto unlinkat = get_actual_function<
int,
int, const char*, int
>("unlinkat");
static auto mmap = get_actual_function<
void*,
void*, size_t, int, int, int, off_t
>("mmap");
}
#endif // CHANGE_SRC_ACTUAL_FUNCTION_H_
|