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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "absl/time/clock.h"
#include "absl/base/config.h"
#if defined(ABSL_HAVE_ALARM)
#include <signal.h>
#include <unistd.h>
#ifdef _AIX
// sig_t is not defined in AIX.
typedef void (*sig_t)(int);
#endif
#elif defined(__linux__) || defined(__APPLE__)
#error all known Linux and Apple targets have alarm
#endif
#include "gtest/gtest.h"
#include "absl/time/time.h"
namespace {
TEST(Time, Now) {
const absl::Time before = absl::FromUnixNanos(absl::GetCurrentTimeNanos());
const absl::Time now = absl::Now();
const absl::Time after = absl::FromUnixNanos(absl::GetCurrentTimeNanos());
EXPECT_GE(now, before);
EXPECT_GE(after, now);
}
enum class AlarmPolicy { kWithoutAlarm, kWithAlarm };
#if defined(ABSL_HAVE_ALARM)
bool alarm_handler_invoked = false;
void AlarmHandler(int signo) {
ASSERT_EQ(signo, SIGALRM);
alarm_handler_invoked = true;
}
#endif
// Does SleepFor(d) take between lower_bound and upper_bound at least
// once between now and (now + timeout)? If requested (and supported),
// add an alarm for the middle of the sleep period and expect it to fire.
bool SleepForBounded(absl::Duration d, absl::Duration lower_bound,
absl::Duration upper_bound, absl::Duration timeout,
AlarmPolicy alarm_policy, int* attempts) {
const absl::Time deadline = absl::Now() + timeout;
while (absl::Now() < deadline) {
#if defined(ABSL_HAVE_ALARM)
sig_t old_alarm = SIG_DFL;
if (alarm_policy == AlarmPolicy::kWithAlarm) {
alarm_handler_invoked = false;
old_alarm = signal(SIGALRM, AlarmHandler);
alarm(absl::ToInt64Seconds(d / 2));
}
#else
EXPECT_EQ(alarm_policy, AlarmPolicy::kWithoutAlarm);
#endif
++*attempts;
absl::Time start = absl::Now();
absl::SleepFor(d);
absl::Duration actual = absl::Now() - start;
#if defined(ABSL_HAVE_ALARM)
if (alarm_policy == AlarmPolicy::kWithAlarm) {
signal(SIGALRM, old_alarm);
if (!alarm_handler_invoked) continue;
}
#endif
if (lower_bound <= actual && actual <= upper_bound) {
return true; // yes, the SleepFor() was correctly bounded
}
}
return false;
}
testing::AssertionResult AssertSleepForBounded(absl::Duration d,
absl::Duration early,
absl::Duration late,
absl::Duration timeout,
AlarmPolicy alarm_policy) {
const absl::Duration lower_bound = d - early;
const absl::Duration upper_bound = d + late;
int attempts = 0;
if (SleepForBounded(d, lower_bound, upper_bound, timeout, alarm_policy,
&attempts)) {
return testing::AssertionSuccess();
}
return testing::AssertionFailure()
<< "SleepFor(" << d << ") did not return within [" << lower_bound
<< ":" << upper_bound << "] in " << attempts << " attempt"
<< (attempts == 1 ? "" : "s") << " over " << timeout
<< (alarm_policy == AlarmPolicy::kWithAlarm ? " with" : " without")
<< " an alarm";
}
// Tests that SleepFor() returns neither too early nor too late.
TEST(SleepFor, Bounded) {
const absl::Duration d = absl::Milliseconds(2500);
const absl::Duration early = absl::Milliseconds(100);
const absl::Duration late = absl::Milliseconds(300);
const absl::Duration timeout = 48 * d;
EXPECT_TRUE(AssertSleepForBounded(d, early, late, timeout,
AlarmPolicy::kWithoutAlarm));
#if defined(ABSL_HAVE_ALARM)
EXPECT_TRUE(AssertSleepForBounded(d, early, late, timeout,
AlarmPolicy::kWithAlarm));
#endif
}
} // namespace