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// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/351564777): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif
#include "mojo/core/ports/port_locker.h"
#include <algorithm>
#include "base/dcheck_is_on.h"
#include "mojo/core/ports/port.h"
#if DCHECK_IS_ON()
#include "base/check_op.h"
#endif
namespace mojo {
namespace core {
namespace ports {
#if DCHECK_IS_ON()
namespace {
constinit thread_local const PortLocker* port_locker = nullptr;
} // namespace
#endif
PortLocker::PortLocker(const PortRef** port_refs, size_t num_ports)
:
#if DCHECK_IS_ON()
resetter_(&port_locker, this, nullptr),
#endif
port_refs_(port_refs),
num_ports_(num_ports) {
// Sort the ports by address to lock them in a globally consistent order.
std::sort(
port_refs_, port_refs_ + num_ports_,
[](const PortRef* a, const PortRef* b) { return a->port() < b->port(); });
for (size_t i = 0; i < num_ports_; ++i) {
// TODO(crbug.com/40522227): Remove this CHECK.
CHECK(port_refs_[i]->port());
port_refs_[i]->port()->lock_.Acquire();
}
}
PortLocker::~PortLocker() {
for (size_t i = 0; i < num_ports_; ++i)
port_refs_[i]->port()->lock_.Release();
#if DCHECK_IS_ON()
DCHECK_EQ(port_locker, this);
#endif
}
#if DCHECK_IS_ON()
// static
void PortLocker::AssertNoPortsLockedOnCurrentThread() {
DCHECK_EQ(port_locker, nullptr);
}
#endif
SinglePortLocker::SinglePortLocker(const PortRef* port_ref)
: port_ref_(port_ref), locker_(&port_ref_, 1) {}
SinglePortLocker::~SinglePortLocker() = default;
} // namespace ports
} // namespace core
} // namespace mojo
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