Atmosphere/libraries/libmesosphere/include/mesosphere/kern_k_unsafe_memory.hpp
2020-04-26 02:35:10 -07:00

79 lines
2.5 KiB
C++

/*
* Copyright (c) 2018-2020 Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <mesosphere/kern_common.hpp>
#include <mesosphere/kern_k_light_lock.hpp>
namespace ams::kern {
class KUnsafeMemory {
private:
mutable KLightLock lock;
size_t limit_size;
size_t current_size;
public:
constexpr KUnsafeMemory() : lock(), limit_size(), current_size() { /* ... */ }
bool TryReserve(size_t size) {
MESOSPHERE_ASSERT_THIS();
KScopedLightLock lk(this->lock);
/* Test for overflow. */
if (this->current_size > this->current_size + size) {
return false;
}
/* Test for limit allowance. */
if (this->current_size + size > this->limit_size) {
return false;
}
/* Reserve the size. */
this->current_size += size;
return true;
}
void Release(size_t size) {
MESOSPHERE_ASSERT_THIS();
KScopedLightLock lk(this->lock);
MESOSPHERE_ABORT_UNLESS(this->current_size >= size);
this->current_size -= size;
}
size_t GetLimitSize() const {
MESOSPHERE_ASSERT_THIS();
KScopedLightLock lk(this->lock);
return this->limit_size;
}
size_t GetCurrentSize() const {
MESOSPHERE_ASSERT_THIS();
KScopedLightLock lk(this->lock);
return this->current_size;
}
Result SetLimitSize(size_t size) {
MESOSPHERE_ASSERT_THIS();
KScopedLightLock lk(this->lock);
R_UNLESS(size >= this->current_size, svc::ResultLimitReached());
this->limit_size = size;
return ResultSuccess();
}
};
}