Object reference counter

// Copyright (c) 2023 Jonathan Metzgar
//
// This software is released under the MIT License.
// https://opensource.org/licenses/MIT

#include <stdlib.h>
#include <stdint.h>
#include <memory.h>

typedef struct Object_t
{
    int64_t refCount;
} Object_t;

typedef Object_t *ObjectPtr;

/**
 * @brief
 *
 * @param obj
 */
static inline
ObjectPtr retainObject(ObjectPtr obj)
{
    if (obj != NULL)
    {
        obj->refCount++;
    }
    return obj;
}

/**
 * @brief Release an object from ownership. Deallocate if reference count <= 0.
 *
 * @param obj
 */
static inline
ObjectPtr releaseObject(ObjectPtr obj)
{
    if (obj != NULL)
    {
        obj->refCount--;
        if (obj->refCount <= 0)
        {
            free(obj);
            return NULL;
        }
    }
    return obj;
}

/**
 * @brief Allocates an object from the heap and adds a reference count.
 *
 * @param sizeInBytes
 * @return ObjectPtr
 */
static inline
ObjectPtr allocObject(size_t sizeInBytes)
{
    ObjectPtr obj = (ObjectPtr)malloc(sizeInBytes);
    if (!obj) {
        return NULL;
    }
    memset(obj, 0, sizeInBytes);
    return retainObject(obj);
}