libfilezilla
Loading...
Searching...
No Matches
util.hpp
Go to the documentation of this file.
1#ifndef LIBFILEZILLA_UTIL_HEADER
2#define LIBFILEZILLA_UTIL_HEADER
3
4#include "libfilezilla.hpp"
5#include "time.hpp"
6
7#include <cstdint>
8
12
13namespace fz {
14
23void FZ_PUBLIC_SYMBOL sleep(duration const& d);
24
29void FZ_PUBLIC_SYMBOL yield();
30
35int64_t FZ_PUBLIC_SYMBOL random_number(int64_t min, int64_t max);
36
41std::vector<uint8_t> FZ_PUBLIC_SYMBOL random_bytes(size_t size);
42
43void FZ_PUBLIC_SYMBOL random_bytes(size_t size, uint8_t* destination);
44
45class buffer;
46void FZ_PUBLIC_SYMBOL random_bytes(size_t size, buffer& destination);
47
54uint64_t FZ_PUBLIC_SYMBOL bitscan(uint64_t v);
55
62uint64_t FZ_PUBLIC_SYMBOL bitscan_reverse(uint64_t v);
63
69bool FZ_PUBLIC_SYMBOL equal_consttime(std::basic_string_view<uint8_t> const& lhs, std::basic_string_view<uint8_t> const& rhs);
70
71template <typename First, typename Second,
72 std::enable_if_t<sizeof(typename First::value_type) == sizeof(uint8_t) &&
73 sizeof(typename Second::value_type) == sizeof(uint8_t)>* = nullptr>
74inline bool equal_consttime(First const& lhs, Second const& rhs)
75{
76 return equal_consttime(std::basic_string_view<uint8_t>(reinterpret_cast<uint8_t const*>(lhs.data()), lhs.size()),
77 std::basic_string_view<uint8_t>(reinterpret_cast<uint8_t const*>(rhs.data()), rhs.size()));
78}
79
94template<typename T, typename std::enable_if_t<std::is_final_v<T>>* = nullptr>
95T& move_assign_through_move_constructor(T* p, T&& op) noexcept
96{
97 p->~T();
98 new (p)T(std::move(op));
99 return *p;
100}
101
107void FZ_PUBLIC_SYMBOL wipe(void* p, size_t n);
108
113void FZ_PUBLIC_SYMBOL wipe(std::string & s);
114void FZ_PUBLIC_SYMBOL wipe(std::wstring & s);
115void FZ_PUBLIC_SYMBOL wipe(std::vector<uint8_t> & v);
116
117template<typename T>
118struct scoped_wiper final
119{
120 [[nodiscard]] scoped_wiper(T& v)
121 : v_(v)
122 {}
123
124 ~scoped_wiper()
125 {
126 wipe(v_);
127 }
128
129 T& v_;
130};
131
136void FZ_PUBLIC_SYMBOL wipe_unused(std::string & s);
137void FZ_PUBLIC_SYMBOL wipe_unused(std::wstring & s);
138void FZ_PUBLIC_SYMBOL wipe_unused(std::vector<uint8_t> & v);
139
141template<class A, class B>
142constexpr bool cmp_less(A a, B b) noexcept
143{
144 static_assert(std::is_integral_v<A>);
145 static_assert(std::is_integral_v<B>);
146 if constexpr (std::is_signed_v<A> == std::is_signed_v<B>) {
147 return a < b;
148 }
149 else if constexpr (std::is_signed_v<A>) {
150 if (a < 0) {
151 return true;
152 }
153 else {
154 return std::make_unsigned_t<A>(a) < b;
155 }
156 }
157 else {
158 if (b < 0) {
159 return false;
160 }
161 else {
162 return a < std::make_unsigned_t<B>(b);
163 }
164 }
165}
166
168template<typename Out, typename In>
169constexpr Out clamped_cast(In in) noexcept
170{
171 if (cmp_less(in, std::numeric_limits<Out>::min())) {
172 return std::numeric_limits<Out>::min();
173 }
174 if (cmp_less(std::numeric_limits<Out>::max(), in)) {
175 return std::numeric_limits<Out>::max();
176 }
177 return static_cast<Out>(in);
178}
179
180}
181
182#endif
The buffer class is a simple buffer where data can be appended at the end and consumed at the front....
Definition buffer.hpp:27
The duration class represents a time interval in milliseconds.
Definition time.hpp:291
Sets some global macros and further includes string.hpp.
The namespace used by libfilezilla.
Definition apply.hpp:17
std::vector< uint8_t > random_bytes(size_t size)
Get random uniformly distributed bytes.
T & move_assign_through_move_constructor(T *p, T &&op) noexcept
Helper to move-assign guaranteeing same member destruction order as the destructor.
Definition util.hpp:95
void yield()
Relinquish control for a brief amount of time.
uint64_t bitscan(uint64_t v)
Returns index of the least-significant set bit.
int64_t random_number(int64_t min, int64_t max)
Get a secure random integer uniformly distributed in the closed interval [min, max].
constexpr bool cmp_less(A a, B b) noexcept
Compares two integers which can be of different sizes and signeness.
Definition util.hpp:142
void sleep(duration const &d)
Sleep current thread for the specified duration.
uint64_t bitscan_reverse(uint64_t v)
Returns index of the most-significant set bit.
constexpr Out clamped_cast(In in) noexcept
Casts to a different integer type, clamping the new value to the min/max of the new type if the origi...
Definition util.hpp:169
bool equal_consttime(std::basic_string_view< uint8_t > const &lhs, std::basic_string_view< uint8_t > const &rhs)
Secure equality test in constant time.
Assorted classes dealing with time.