summaryrefslogtreecommitdiffstats
path: root/src/core/hle/kernel/kernel.h
diff options
context:
space:
mode:
Diffstat (limited to 'src/core/hle/kernel/kernel.h')
-rw-r--r--src/core/hle/kernel/kernel.h196
1 files changed, 112 insertions, 84 deletions
diff --git a/src/core/hle/kernel/kernel.h b/src/core/hle/kernel/kernel.h
index 32258d5a0..7f86fd07d 100644
--- a/src/core/hle/kernel/kernel.h
+++ b/src/core/hle/kernel/kernel.h
@@ -12,13 +12,17 @@
typedef u32 Handle;
typedef s32 Result;
+const Handle INVALID_HANDLE = 0;
+
namespace Kernel {
-// From kernel.h. Declarations duplicated here to avoid a circular header dependency.
-class Thread;
-Thread* GetCurrentThread();
+// TODO: Verify code
+const ResultCode ERR_OUT_OF_HANDLES(ErrorDescription::OutOfMemory, ErrorModule::Kernel,
+ ErrorSummary::OutOfResource, ErrorLevel::Temporary);
+// TOOD: Verify code
+const ResultCode ERR_INVALID_HANDLE = InvalidHandle(ErrorModule::Kernel);
-enum KernelHandle {
+enum KernelHandle : Handle {
CurrentThread = 0xFFFF8000,
CurrentProcess = 0xFFFF8001,
};
@@ -41,10 +45,10 @@ enum {
DEFAULT_STACK_SIZE = 0x4000,
};
-class ObjectPool;
+class HandleTable;
class Object : NonCopyable {
- friend class ObjectPool;
+ friend class HandleTable;
u32 handle;
public:
virtual ~Object() {}
@@ -61,106 +65,130 @@ public:
LOG_ERROR(Kernel, "(UNIMPLEMENTED)");
return UnimplementedFunction(ErrorModule::Kernel);
}
-};
-class ObjectPool : NonCopyable {
-public:
- ObjectPool();
- ~ObjectPool() {}
+private:
+ friend void intrusive_ptr_add_ref(Object*);
+ friend void intrusive_ptr_release(Object*);
- // Allocates a handle within the range and inserts the object into the map.
- Handle Create(Object* obj, int range_bottom=INITIAL_NEXT_ID, int range_top=0x7FFFFFFF);
+ unsigned int ref_count = 0;
+};
- static Object* CreateByIDType(int type);
+// Special functions that will later be used by boost::instrusive_ptr to do automatic ref-counting
+inline void intrusive_ptr_add_ref(Object* object) {
+ ++object->ref_count;
+}
- template <class T>
- void Destroy(Handle handle) {
- if (Get<T>(handle)) {
- occupied[handle - HANDLE_OFFSET] = false;
- delete pool[handle - HANDLE_OFFSET];
- }
+inline void intrusive_ptr_release(Object* object) {
+ if (--object->ref_count == 0) {
+ delete object;
}
+}
- bool IsValid(Handle handle) const;
+/**
+ * This class allows the creation of Handles, which are references to objects that can be tested
+ * for validity and looked up. Here they are used to pass references to kernel objects to/from the
+ * emulated process. it has been designed so that it follows the same handle format and has
+ * approximately the same restrictions as the handle manager in the CTR-OS.
+ *
+ * Handles contain two sub-fields: a slot index (bits 31:15) and a generation value (bits 14:0).
+ * The slot index is used to index into the arrays in this class to access the data corresponding
+ * to the Handle.
+ *
+ * To prevent accidental use of a freed Handle whose slot has already been reused, a global counter
+ * is kept and incremented every time a Handle is created. This is the Handle's "generation". The
+ * value of the counter is stored into the Handle as well as in the handle table (in the
+ * "generations" array). When looking up a handle, the Handle's generation must match with the
+ * value stored on the class, otherwise the Handle is considered invalid.
+ *
+ * To find free slots when allocating a Handle without needing to scan the entire object array, the
+ * generations field of unallocated slots is re-purposed as a linked list of indices to free slots.
+ * When a Handle is created, an index is popped off the list and used for the new Handle. When it
+ * is destroyed, it is again pushed onto the list to be re-used by the next allocation. It is
+ * likely that this allocation strategy differs from the one used in CTR-OS, but this hasn't been
+ * verified and isn't likely to cause any problems.
+ */
+class HandleTable final : NonCopyable {
+public:
+ HandleTable();
- template <class T>
- T* Get(Handle handle) {
- if (handle == CurrentThread) {
- return reinterpret_cast<T*>(GetCurrentThread());
- }
+ /**
+ * Allocates a handle for the given object.
+ * @return The created Handle or one of the following errors:
+ * - `ERR_OUT_OF_HANDLES`: the maximum number of handles has been exceeded.
+ */
+ ResultVal<Handle> Create(Object* obj);
- if (handle < HANDLE_OFFSET || handle >= HANDLE_OFFSET + MAX_COUNT || !occupied[handle - HANDLE_OFFSET]) {
- if (handle != 0) {
- LOG_ERROR(Kernel, "Bad object handle %08x", handle);
- }
- return nullptr;
- } else {
- Object* t = pool[handle - HANDLE_OFFSET];
- if (t->GetHandleType() != T::GetStaticHandleType()) {
- LOG_ERROR(Kernel, "Wrong object type for %08x", handle);
- return nullptr;
- }
- return static_cast<T*>(t);
- }
- }
+ /**
+ * Returns a new handle that points to the same object as the passed in handle.
+ * @return The duplicated Handle or one of the following errors:
+ * - `ERR_INVALID_HANDLE`: an invalid handle was passed in.
+ * - Any errors returned by `Create()`.
+ */
+ ResultVal<Handle> Duplicate(Handle handle);
- // ONLY use this when you know the handle is valid.
- template <class T>
- T *GetFast(Handle handle) {
- if (handle == CurrentThread) {
- return reinterpret_cast<T*>(GetCurrentThread());
- }
+ /**
+ * Closes a handle, removing it from the table and decreasing the object's ref-count.
+ * @return `RESULT_SUCCESS` or one of the following errors:
+ * - `ERR_INVALID_HANDLE`: an invalid handle was passed in.
+ */
+ ResultCode Close(Handle handle);
- const Handle realHandle = handle - HANDLE_OFFSET;
- _dbg_assert_(Kernel, realHandle >= 0 && realHandle < MAX_COUNT && occupied[realHandle]);
- return static_cast<T*>(pool[realHandle]);
- }
+ /// Checks if a handle is valid and points to an existing object.
+ bool IsValid(Handle handle) const;
- template <class T, typename ArgT>
- void Iterate(bool func(T*, ArgT), ArgT arg) {
- int type = T::GetStaticIDType();
- for (int i = 0; i < MAX_COUNT; i++)
- {
- if (!occupied[i])
- continue;
- T* t = static_cast<T*>(pool[i]);
- if (t->GetIDType() == type) {
- if (!func(t, arg))
- break;
- }
- }
- }
+ /**
+ * Looks up a handle.
+ * @returns Pointer to the looked-up object, or `nullptr` if the handle is not valid.
+ */
+ Object* GetGeneric(Handle handle) const;
- bool GetIDType(Handle handle, HandleType* type) const {
- if ((handle < HANDLE_OFFSET) || (handle >= HANDLE_OFFSET + MAX_COUNT) ||
- !occupied[handle - HANDLE_OFFSET]) {
- LOG_ERROR(Kernel, "Bad object handle %08X", handle);
- return false;
+ /**
+ * Looks up a handle while verifying its type.
+ * @returns Pointer to the looked-up object, or `nullptr` if the handle is not valid or its
+ * type differs from the handle type `T::HANDLE_TYPE`.
+ */
+ template <class T>
+ T* Get(Handle handle) const {
+ Object* object = GetGeneric(handle);
+ if (object != nullptr && object->GetHandleType() == T::HANDLE_TYPE) {
+ return static_cast<T*>(object);
}
- Object* t = pool[handle - HANDLE_OFFSET];
- *type = t->GetHandleType();
- return true;
+ return nullptr;
}
- Object* &operator [](Handle handle);
- void List();
+ /// Closes all handles held in this table.
void Clear();
- int GetCount() const;
private:
+ /**
+ * This is the maximum limit of handles allowed per process in CTR-OS. It can be further
+ * reduced by ExHeader values, but this is not emulated here.
+ */
+ static const size_t MAX_COUNT = 4096;
+
+ static size_t GetSlot(Handle handle) { return handle >> 15; }
+ static u16 GetGeneration(Handle handle) { return handle & 0x7FFF; }
+
+ /// Stores the Object referenced by the handle or null if the slot is empty.
+ std::array<Object*, MAX_COUNT> objects;
- enum {
- MAX_COUNT = 0x1000,
- HANDLE_OFFSET = 0x100,
- INITIAL_NEXT_ID = 0x10,
- };
+ /**
+ * The value of `next_generation` when the handle was created, used to check for validity. For
+ * empty slots, contains the index of the next free slot in the list.
+ */
+ std::array<u16, MAX_COUNT> generations;
+
+ /**
+ * Global counter of the number of created handles. Stored in `generations` when a handle is
+ * created, and wraps around to 1 when it hits 0x8000.
+ */
+ u16 next_generation;
- std::array<Object*, MAX_COUNT> pool;
- std::array<bool, MAX_COUNT> occupied;
- int next_id;
+ /// Head of the free slots linked list.
+ u16 next_free_slot;
};
-extern ObjectPool g_object_pool;
+extern HandleTable g_handle_table;
extern Handle g_main_thread;
/// The ID code of the currently running game