// SPDX-FileCopyrightText: Copyright 2021 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#pragma once
#include <array>
#include "common/assert.h"
#include "common/bit_field.h"
#include "common/common_types.h"
#include "core/hle/kernel/k_auto_object.h"
#include "core/hle/kernel/k_spin_lock.h"
#include "core/hle/kernel/k_thread.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/svc_common.h"
#include "core/hle/kernel/svc_results.h"
#include "core/hle/result.h"
namespace Kernel {
class KernelCore;
class KHandleTable {
YUZU_NON_COPYABLE(KHandleTable);
YUZU_NON_MOVEABLE(KHandleTable);
public:
static constexpr size_t MaxTableSize = 1024;
public:
explicit KHandleTable(KernelCore& kernel) : m_kernel(kernel) {}
Result Initialize(s32 size) {
// Check that the table size is valid.
R_UNLESS(size <= static_cast<s32>(MaxTableSize), ResultOutOfMemory);
// Lock.
KScopedDisableDispatch dd{m_kernel};
KScopedSpinLock lk(m_lock);
// Initialize all fields.
m_max_count = 0;
m_table_size = static_cast<s16>((size <= 0) ? MaxTableSize : size);
m_next_linear_id = MinLinearId;
m_count = 0;
m_free_head_index = -1;
// Free all entries.
for (s32 i = 0; i < static_cast<s32>(m_table_size); ++i) {
m_objects[i] = nullptr;
m_entry_infos[i].next_free_index = static_cast<s16>(i - 1);
m_free_head_index = i;
}
R_SUCCEED();
}
size_t GetTableSize() const {
return m_table_size;
}
size_t GetCount() const {
return m_count;
}
size_t GetMaxCount() const {
return m_max_count;
}
Result Finalize();
bool Remove(Handle handle);
template <typename T = KAutoObject>
KScopedAutoObject<T> GetObjectWithoutPseudoHandle(Handle handle) const {
// Lock and look up in table.
KScopedDisableDispatch dd{m_kernel};
KScopedSpinLock lk(m_lock);
if constexpr (std::is_same<T, KAutoObject>::value) {
return this->GetObjectImpl(handle);
} else {
if (auto* obj = this->GetObjectImpl(handle); obj != nullptr) [[likely]] {
return obj->DynamicCast<T*>();
} else {
return nullptr;
}
}
}
template <typename T = KAutoObject>
KScopedAutoObject<T> GetObject(Handle handle) const {
// Handle pseudo-handles.
if constexpr (std::derived_from<KProcess, T>) {
if (handle == Svc::PseudoHandle::CurrentProcess) {
auto* const cur_process = m_kernel.CurrentProcess();
ASSERT(cur_process != nullptr);
return cur_process;
}
} else if constexpr (std::derived_from<KThread, T>) {
if (handle == Svc::PseudoHandle::CurrentThread) {
auto* const cur_thread = GetCurrentThreadPointer(m_kernel);
ASSERT(cur_thread != nullptr);
return cur_thread;
}
}
return this->template GetObjectWithoutPseudoHandle<T>(handle);
}
KScopedAutoObject<KAutoObject> GetObjectForIpcWithoutPseudoHandle(Handle handle) const {
// Lock and look up in table.
KScopedDisableDispatch dd{m_kernel};
KScopedSpinLock lk(m_lock);
return this->GetObjectImpl(handle);
}
KScopedAutoObject<KAutoObject> GetObjectForIpc(Handle handle, KThread* cur_thread) const {
// Handle pseudo-handles.
ASSERT(cur_thread != nullptr);
if (handle == Svc::PseudoHandle::CurrentProcess) {
auto* const cur_process =
static_cast<KAutoObject*>(static_cast<void*>(cur_thread->GetOwnerProcess()));
ASSERT(cur_process != nullptr);
return cur_process;
}
if (handle == Svc::PseudoHandle::CurrentThread) {
return static_cast<KAutoObject*>(cur_thread);
}
return GetObjectForIpcWithoutPseudoHandle(handle);
}
KScopedAutoObject<KAutoObject> GetObjectByIndex(Handle* out_handle, size_t index) const {
KScopedDisableDispatch dd{m_kernel};
KScopedSpinLock lk(m_lock);
return this->GetObjectByIndexImpl(out_handle, index);
}
Result Reserve(Handle* out_handle);
void Unreserve(Handle handle);
Result Add(Handle* out_handle, KAutoObject* obj);
void Register(Handle handle, KAutoObject* obj);
template <typename T>
bool GetMultipleObjects(T** out, const Handle* handles, size_t num_handles) const {
// Try to convert and open all the handles.
size_t num_opened;
{
// Lock the table.
KScopedDisableDispatch dd{m_kernel};
KScopedSpinLock lk(m_lock);
for (num_opened = 0; num_opened < num_handles; num_opened++) {
// Get the current handle.
const auto cur_handle = handles[num_opened];
// Get the object for the current handle.
KAutoObject* cur_object = this->GetObjectImpl(cur_handle);
if (cur_object == nullptr) [[unlikely]] {
break;
}
// Cast the current object to the desired type.
T* cur_t = cur_object->DynamicCast<T*>();
if (cur_t == nullptr) [[unlikely]] {
break;
}
// Open a reference to the current object.
cur_t->Open();
out[num_opened] = cur_t;
}
}
// If we converted every object, succeed.
if (num_opened == num_handles) [[likely]] {
return true;
}
// If we didn't convert entry object, close the ones we opened.
for (size_t i = 0; i < num_opened; i++) {
out[i]->Close();
}
return false;
}
private:
s32 AllocateEntry() {
ASSERT(m_count < m_table_size);
const auto index = m_free_head_index;
m_free_head_index = m_entry_infos[index].GetNextFreeIndex();
m_max_count = std::max(m_max_count, ++m_count);
return index;
}
void FreeEntry(s32 index) {
ASSERT(m_count > 0);
m_objects[index] = nullptr;
m_entry_infos[index].next_free_index = static_cast<s16>(m_free_head_index);
m_free_head_index = index;
--m_count;
}
u16 AllocateLinearId() {
const u16 id = m_next_linear_id++;
if (m_next_linear_id > MaxLinearId) {
m_next_linear_id = MinLinearId;
}
return id;
}
bool IsValidHandle(Handle handle) const {
// Unpack the handle.
const auto handle_pack = HandlePack(handle);
const auto raw_value = handle_pack.raw;
const auto index = handle_pack.index;
const auto linear_id = handle_pack.linear_id;
const auto reserved = handle_pack.reserved;
ASSERT(reserved == 0);
// Validate our indexing information.
if (raw_value == 0) [[unlikely]] {
return false;
}
if (linear_id == 0) [[unlikely]] {
return false;
}
if (index >= m_table_size) [[unlikely]] {
return false;
}
// Check that there's an object, and our serial id is correct.
if (m_objects[index] == nullptr) [[unlikely]] {
return false;
}
if (m_entry_infos[index].GetLinearId() != linear_id) [[unlikely]] {
return false;
}
return true;
}
KAutoObject* GetObjectImpl(Handle handle) const {
// Handles must not have reserved bits set.
const auto handle_pack = HandlePack(handle);
if (handle_pack.reserved != 0) [[unlikely]] {
return nullptr;
}
if (this->IsValidHandle(handle)) [[likely]] {
return m_objects[handle_pack.index];
} else {
return nullptr;
}
}
KAutoObject* GetObjectByIndexImpl(Handle* out_handle, size_t index) const {
// Index must be in bounds.
if (index >= m_table_size) [[unlikely]] {
return nullptr;
}
// Ensure entry has an object.
if (KAutoObject* obj = m_objects[index]; obj != nullptr) {
*out_handle = EncodeHandle(static_cast<u16>(index), m_entry_infos[index].GetLinearId());
return obj;
} else {
return nullptr;
}
}
private:
union HandlePack {
constexpr HandlePack() = default;
constexpr HandlePack(Handle handle) : raw{static_cast<u32>(handle)} {}
u32 raw{};
BitField<0, 15, u32> index;
BitField<15, 15, u32> linear_id;
BitField<30, 2, u32> reserved;
};
static constexpr Handle EncodeHandle(u16 index, u16 linear_id) {
HandlePack handle{};
handle.index.Assign(index);
handle.linear_id.Assign(linear_id);
handle.reserved.Assign(0);
return handle.raw;
}
private:
static constexpr u16 MinLinearId = 1;
static constexpr u16 MaxLinearId = 0x7FFF;
union EntryInfo {
u16 linear_id;
s16 next_free_index;
constexpr u16 GetLinearId() const {
return linear_id;
}
constexpr s32 GetNextFreeIndex() const {
return next_free_index;
}
};
private:
KernelCore& m_kernel;
std::array<EntryInfo, MaxTableSize> m_entry_infos{};
std::array<KAutoObject*, MaxTableSize> m_objects{};
mutable KSpinLock m_lock;
s32 m_free_head_index{};
u16 m_table_size{};
u16 m_max_count{};
u16 m_next_linear_id{};
u16 m_count{};
};
} // namespace Kernel