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
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you 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
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// 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 "contrib/libs/apache/arrow_next/cpp/src/arrow/util/counting_semaphore.h"
#include <chrono>
#include <condition_variable>
#include <cstdint>
#include <iostream>
#include <mutex>
#include "contrib/libs/apache/arrow_next/cpp/src/arrow/status.h"
namespace arrow20 {
namespace util {
class CountingSemaphore::Impl {
public:
Impl(uint32_t initial_avail, double timeout_seconds)
: num_permits_(initial_avail), timeout_seconds_(timeout_seconds) {}
Status Acquire(uint32_t num_permits) {
std::unique_lock<std::mutex> lk(mutex_);
RETURN_NOT_OK(CheckClosed());
num_waiters_ += num_permits;
waiter_cv_.notify_all();
bool timed_out = !acquirer_cv_.wait_for(
lk, std::chrono::nanoseconds(static_cast<int64_t>(timeout_seconds_ * 1e9)),
[&] { return closed_ || num_permits <= num_permits_; });
num_waiters_ -= num_permits;
if (timed_out) {
return Status::Invalid("Timed out waiting for semaphore to release ", num_permits,
" permits.");
}
if (closed_) {
return Status::Invalid("Semaphore closed while acquiring");
}
num_permits_ -= num_permits;
return Status::OK();
}
Status Release(uint32_t num_permits) {
std::lock_guard<std::mutex> lg(mutex_);
RETURN_NOT_OK(CheckClosed());
num_permits_ += num_permits;
acquirer_cv_.notify_all();
return Status::OK();
}
Status WaitForWaiters(uint32_t num_waiters) {
std::unique_lock<std::mutex> lk(mutex_);
RETURN_NOT_OK(CheckClosed());
if (waiter_cv_.wait_for(
lk, std::chrono::nanoseconds(static_cast<int64_t>(timeout_seconds_ * 1e9)),
[&] { return closed_ || num_waiters <= num_waiters_; })) {
if (closed_) {
return Status::Invalid("Semaphore closed while waiting for waiters");
}
return Status::OK();
}
return Status::Invalid("Timed out waiting for ", num_waiters,
" to start waiting on semaphore");
}
Status Close() {
std::lock_guard<std::mutex> lg(mutex_);
RETURN_NOT_OK(CheckClosed());
closed_ = true;
if (num_waiters_ > 0) {
waiter_cv_.notify_all();
acquirer_cv_.notify_all();
return Status::Invalid(
"There were one or more threads waiting on a semaphore when it was closed");
}
return Status::OK();
}
private:
Status CheckClosed() const {
if (closed_) {
return Status::Invalid("Invalid operation on closed semaphore");
}
return Status::OK();
}
uint32_t num_permits_;
double timeout_seconds_;
uint32_t num_waiters_ = 0;
bool closed_ = false;
std::mutex mutex_;
std::condition_variable acquirer_cv_;
std::condition_variable waiter_cv_;
};
CountingSemaphore::CountingSemaphore(uint32_t initial_avail, double timeout_seconds)
: impl_(new Impl(initial_avail, timeout_seconds)) {}
CountingSemaphore::~CountingSemaphore() = default;
Status CountingSemaphore::Acquire(uint32_t num_permits) {
return impl_->Acquire(num_permits);
}
Status CountingSemaphore::Release(uint32_t num_permits) {
return impl_->Release(num_permits);
}
Status CountingSemaphore::WaitForWaiters(uint32_t num_waiters) {
return impl_->WaitForWaiters(num_waiters);
}
Status CountingSemaphore::Close() { return impl_->Close(); }
} // namespace util
} // namespace arrow20
|
