Inside Bitcoin

1// Copyright (c) 2015-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#include <sync.h>
6#include <test/util/common.h>
7
8#include <boost/test/unit_test.hpp>
9
10#include <stdexcept>
11
12BOOST_AUTO_TEST_SUITE(reverselock_tests)
13
14BOOST_AUTO_TEST_CASE(reverselock_basics)
15{
16    Mutex mutex;
17    WAIT_LOCK(mutex, lock);
18
19    BOOST_CHECK(lock.owns_lock());
20    AssertLockHeld(mutex);
21    {
22        REVERSE_LOCK(lock, mutex);
23        AssertLockNotHeld(mutex);
24        BOOST_CHECK(!lock.owns_lock());
25    }
26    BOOST_CHECK(lock.owns_lock());
27}
28
29BOOST_AUTO_TEST_CASE(reverselock_multiple)
30{
31    Mutex mutex2;
32    Mutex mutex;
33    WAIT_LOCK(mutex2, lock2);
34    WAIT_LOCK(mutex, lock);
35
36    // Make sure undoing two locks succeeds
37    {
38        REVERSE_LOCK(lock, mutex);
39        BOOST_CHECK(!lock.owns_lock());
40        REVERSE_LOCK(lock2, mutex2);
41        BOOST_CHECK(!lock2.owns_lock());
42    }
43    BOOST_CHECK(lock.owns_lock());
44    BOOST_CHECK(lock2.owns_lock());
45}
46
47BOOST_AUTO_TEST_CASE(reverselock_errors)
48{
49    Mutex mutex2;
50    Mutex mutex;
51    WAIT_LOCK(mutex2, lock2);
52    WAIT_LOCK(mutex, lock);
53
54#ifdef DEBUG_LOCKORDER
55    bool prev = g_debug_lockorder_abort;
56    g_debug_lockorder_abort = false;
57
58    // Make sure trying to reverse lock a previous lock fails
59    BOOST_CHECK_EXCEPTION(REVERSE_LOCK(lock2, mutex2), std::logic_error, HasReason{"mutex2 was not most recent critical section locked"});
60    BOOST_CHECK(lock2.owns_lock());
61
62    g_debug_lockorder_abort = prev;
63#endif
64
65    // Make sure trying to reverse lock an unlocked lock fails
66    lock.unlock();
67
68    BOOST_CHECK(!lock.owns_lock());
69
70    BOOST_CHECK_EXCEPTION(REVERSE_LOCK(lock, mutex), std::system_error,
71                          [](const std::system_error& e) { return e.code() == std::errc::operation_not_permitted; });
72
73    BOOST_CHECK(!lock.owns_lock());
74
75    // Locking the original lock after it has been taken by a reverse lock
76    // makes no sense. Ensure that the original lock no longer owns the lock
77    // after giving it to a reverse one.
78
79    lock.lock();
80    BOOST_CHECK(lock.owns_lock());
81    {
82        REVERSE_LOCK(lock, mutex);
83        BOOST_CHECK(!lock.owns_lock());
84    }
85
86    BOOST_CHECK(lock.owns_lock());
87}
88
89BOOST_AUTO_TEST_SUITE_END()
90