mirror of
https://github.com/wpilibsuite/allwpilib
synced 2026-06-19 00:41:43 +00:00
114 lines
4.0 KiB
C++
114 lines
4.0 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/Handles.h"
|
|
#include "HAL/cpp/priority_mutex.h"
|
|
#include "HandlesInternal.h"
|
|
|
|
namespace hal {
|
|
|
|
/**
|
|
* The LimitedHandleResource class is a way to track handles. This version
|
|
* allows a limited number of handles that are allocated sequentially.
|
|
*
|
|
* @tparam THandle The Handle Type (Must be typedefed from HAL_Handle)
|
|
* @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,
|
|
HAL_HandleEnum enumValue>
|
|
class LimitedHandleResource {
|
|
friend class LimitedHandleResourceTest;
|
|
|
|
public:
|
|
LimitedHandleResource(const LimitedHandleResource&) = delete;
|
|
LimitedHandleResource operator=(const LimitedHandleResource&) = delete;
|
|
LimitedHandleResource();
|
|
~LimitedHandleResource();
|
|
THandle Allocate();
|
|
std::shared_ptr<TStruct> Get(THandle handle);
|
|
void Free(THandle handle);
|
|
|
|
private:
|
|
// Dynamic array to shrink HAL file size.
|
|
std::shared_ptr<TStruct>* m_structures;
|
|
priority_mutex* m_handleMutexes;
|
|
priority_mutex m_allocateMutex;
|
|
};
|
|
|
|
template <typename THandle, typename TStruct, int16_t size,
|
|
HAL_HandleEnum enumValue>
|
|
LimitedHandleResource<THandle, TStruct, size,
|
|
enumValue>::LimitedHandleResource() {
|
|
m_structures = new std::shared_ptr<TStruct>[size];
|
|
m_handleMutexes = new priority_mutex[size];
|
|
}
|
|
|
|
template <typename THandle, typename TStruct, int16_t size,
|
|
HAL_HandleEnum enumValue>
|
|
LimitedHandleResource<THandle, TStruct, size,
|
|
enumValue>::~LimitedHandleResource() {
|
|
delete[] m_structures;
|
|
delete[] m_handleMutexes;
|
|
}
|
|
|
|
template <typename THandle, typename TStruct, int16_t size,
|
|
HAL_HandleEnum enumValue>
|
|
THandle LimitedHandleResource<THandle, TStruct, size, enumValue>::Allocate() {
|
|
// globally lock to loop through indices
|
|
std::lock_guard<priority_mutex> sync(m_allocateMutex);
|
|
int16_t i;
|
|
for (i = 0; i < size; i++) {
|
|
if (m_structures[i] == nullptr) {
|
|
// if a false index is found, grab its specific mutex
|
|
// and allocate it.
|
|
std::lock_guard<priority_mutex> sync(m_handleMutexes[i]);
|
|
m_structures[i] = std::make_shared<TStruct>();
|
|
return (THandle)createHandle(i, enumValue);
|
|
}
|
|
}
|
|
return HAL_kInvalidHandle;
|
|
}
|
|
|
|
template <typename THandle, typename TStruct, int16_t size,
|
|
HAL_HandleEnum enumValue>
|
|
std::shared_ptr<TStruct>
|
|
LimitedHandleResource<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,
|
|
HAL_HandleEnum enumValue>
|
|
void LimitedHandleResource<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_allocateMutex);
|
|
std::lock_guard<priority_mutex> lock(m_handleMutexes[index]);
|
|
m_structures[index].reset();
|
|
}
|
|
}
|