/*

 * Copyright © 2018, VideoLAN and dav1d authors

 * Copyright © 2018, Two Orioles, LLC

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 * 1. Redistributions of source code must retain the above copyright notice, this

 *    list of conditions and the following disclaimer.

 *

 * 2. Redistributions in binary form must reproduce the above copyright notice,

 *    this list of conditions and the following disclaimer in the documentation

 *    and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR

 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include "config.h"

#include "src/ref.h"

static void default_free_callback(const uint8_t *const data, void *const user_data) {

    assert(data == user_data);

    dav1d_free_aligned(user_data);

}

Dav1dRef *dav1d_ref_create(const enum AllocationType type, size_t size) {

    size = (size + sizeof(void*) - 1) & ~(sizeof(void*) - 1);

    uint8_t *const data = dav1d_alloc_aligned(type, size + sizeof(Dav1dRef), 64);

    if (!data) return NULL;

    Dav1dRef *const res = (Dav1dRef*)(data + size);

    res->const_data = res->user_data = res->data = data;

    atomic_init(&res->ref_cnt, 1);

    res->free_ref = 0;

    res->free_callback = default_free_callback;

    return res;

}

static void pool_free_callback(const uint8_t *const data, void *const user_data) {

    dav1d_mem_pool_push((Dav1dMemPool*)data, user_data);

}

Dav1dRef *dav1d_ref_create_using_pool(Dav1dMemPool *const pool, size_t size) {

    void *const buf = dav1d_mem_pool_pop(pool, size);

    if (!buf) return NULL;

    /* Store Dav1dRef inside the Dav1dMemPoolBuffer alignment padding */

    assert(sizeof(Dav1dMemPoolBuffer) + sizeof(Dav1dRef) <= 64);

    Dav1dRef *const res = &((Dav1dRef*)buf)[-1];

    res->data = buf;

    res->const_data = pool;

    atomic_init(&res->ref_cnt, 1);

    res->free_ref = 0;

    res->free_callback = pool_free_callback;

    res->user_data = buf;

    return res;

}

void dav1d_ref_dec(Dav1dRef **const pref) {

    assert(pref != NULL);

    Dav1dRef *const ref = *pref;

    if (!ref) return;

    *pref = NULL;

    if (atomic_fetch_sub(&ref->ref_cnt, 1) == 1) {

        const int free_ref = ref->free_ref;

        ref->free_callback(ref->const_data, ref->user_data);

        if (free_ref) dav1d_free(ref);

    }

}