1/*
2 * Copyright 2016-present Facebook, Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <folly/portability/SysTime.h>
18
19#ifdef _WIN32
20
21#include <cstdint>
22
23extern "C" {
24int gettimeofday(timeval* tv, struct timezone*) {
25 constexpr auto posixWinFtOffset = 116444736000000000ULL;
26
27 if (tv) {
28 FILETIME ft;
29 ULARGE_INTEGER lft;
30 GetSystemTimeAsFileTime(&ft);
31 // As per the docs of FILETIME, don't just do an indirect
32 // pointer cast, to avoid alignment faults.
33 lft.HighPart = ft.dwHighDateTime;
34 lft.LowPart = ft.dwLowDateTime;
35 uint64_t ns = lft.QuadPart;
36 tv->tv_usec = (long)((ns / 10ULL) % 1000000ULL);
37 tv->tv_sec = (long)((ns - posixWinFtOffset) / 10000000ULL);
38 }
39
40 return 0;
41}
42
43void timeradd(timeval* a, timeval* b, timeval* res) {
44 res->tv_sec = a->tv_sec + b->tv_sec;
45 res->tv_usec = a->tv_usec + b->tv_usec;
46 if (res->tv_usec >= 1000000) {
47 res->tv_sec++;
48 res->tv_usec -= 1000000;
49 }
50}
51
52void timersub(timeval* a, timeval* b, timeval* res) {
53 res->tv_sec = a->tv_sec - b->tv_sec;
54 res->tv_usec = a->tv_usec - b->tv_usec;
55 if (res->tv_usec < 0) {
56 res->tv_sec--;
57 res->tv_usec += 1000000;
58 }
59}
60}
61
62#endif
63