mirror of
https://github.com/wpilibsuite/allwpilib
synced 2026-06-25 01:41:43 +00:00
3cacc2aba6
As discussed, the old method of was going to have issues, and was not going to help in the case of the structs containing pointers. I think we are just going to have to be careful, as guarenteeing the internal pointers are const is going to be very difficult.
98 lines
3.5 KiB
C++
98 lines
3.5 KiB
C++
/*----------------------------------------------------------------------------*/
|
|
/* Copyright (c) FIRST 2016. All Rights Reserved. */
|
|
/* Open Source Software - may be modified and shared by FRC teams. The code */
|
|
/* must be accompanied by the FIRST BSD license file in the root directory of */
|
|
/* the project. */
|
|
/*----------------------------------------------------------------------------*/
|
|
|
|
#pragma once
|
|
|
|
#include <stdint.h>
|
|
|
|
#include <memory>
|
|
#include <vector>
|
|
|
|
#include "HAL/Errors.h"
|
|
#include "HAL/Handles.h"
|
|
#include "HAL/cpp/priority_mutex.h"
|
|
#include "HandlesInternal.h"
|
|
|
|
namespace hal {
|
|
|
|
/**
|
|
* The IndexedHandleResource class is a way to track handles. This version
|
|
* allows a limited number of handles that are allocated by index.
|
|
* Because they are allocated by index, each individual index holds its own
|
|
* mutex, which reduces contention heavily.]
|
|
*
|
|
* @tparam THandle The Handle Type (Must be typedefed from HalHandle)
|
|
* @tparam TStruct The struct type held by this resource
|
|
* @tparam size The number of resources allowed to be allocated
|
|
* @tparam enumValue The type value stored in the handle
|
|
*
|
|
*/
|
|
template <typename THandle, typename TStruct, int16_t size,
|
|
HalHandleEnum enumValue>
|
|
class IndexedHandleResource {
|
|
friend class IndexedHandleResourceTest;
|
|
|
|
public:
|
|
IndexedHandleResource(const IndexedHandleResource&) = delete;
|
|
IndexedHandleResource operator=(const IndexedHandleResource&) = delete;
|
|
IndexedHandleResource() = default;
|
|
THandle Allocate(int16_t index, int32_t* status);
|
|
std::shared_ptr<TStruct> Get(THandle handle);
|
|
void Free(THandle handle);
|
|
|
|
private:
|
|
std::shared_ptr<TStruct> m_structures[size];
|
|
priority_mutex m_handleMutexes[size];
|
|
};
|
|
|
|
template <typename THandle, typename TStruct, int16_t size,
|
|
HalHandleEnum enumValue>
|
|
THandle IndexedHandleResource<THandle, TStruct, size, enumValue>::Allocate(
|
|
int16_t index, int32_t* status) {
|
|
// don't aquire the lock if we can fail early.
|
|
if (index < 0 || index >= size) {
|
|
*status = PARAMETER_OUT_OF_RANGE;
|
|
return HAL_INVALID_HANDLE;
|
|
}
|
|
std::lock_guard<priority_mutex> sync(m_handleMutexes[index]);
|
|
// check for allocation, otherwise allocate and return a valid handle
|
|
if (m_structures[index] != nullptr) {
|
|
*status = RESOURCE_IS_ALLOCATED;
|
|
return HAL_INVALID_HANDLE;
|
|
}
|
|
m_structures[index] = std::make_shared<TStruct>();
|
|
return (THandle)hal::createHandle(index, enumValue);
|
|
}
|
|
|
|
template <typename THandle, typename TStruct, int16_t size,
|
|
HalHandleEnum enumValue>
|
|
std::shared_ptr<TStruct>
|
|
IndexedHandleResource<THandle, TStruct, size, enumValue>::Get(THandle handle) {
|
|
// get handle index, and fail early if index out of range or wrong handle
|
|
int16_t index = getHandleTypedIndex(handle, enumValue);
|
|
if (index < 0 || index >= size) {
|
|
return nullptr;
|
|
}
|
|
std::lock_guard<priority_mutex> sync(m_handleMutexes[index]);
|
|
// return structure. Null will propogate correctly, so no need to manually
|
|
// check.
|
|
return m_structures[index];
|
|
}
|
|
|
|
template <typename THandle, typename TStruct, int16_t size,
|
|
HalHandleEnum enumValue>
|
|
void IndexedHandleResource<THandle, TStruct, size, enumValue>::Free(
|
|
THandle handle) {
|
|
// get handle index, and fail early if index out of range or wrong handle
|
|
int16_t index = getHandleTypedIndex(handle, enumValue);
|
|
if (index < 0 || index >= size) return;
|
|
// lock and deallocated handle
|
|
std::lock_guard<priority_mutex> sync(m_handleMutexes[index]);
|
|
m_structures[index].reset();
|
|
}
|
|
}
|