FFmpeg4/compat/atomics/pthread/stdatomic.h

/*
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/*
 * based on vlc_atomic.h from VLC
 * Copyright (C) 2010 Rémi Denis-Courmont
 */

#ifndef COMPAT_ATOMICS_PTHREAD_STDATOMIC_H
#define COMPAT_ATOMICS_PTHREAD_STDATOMIC_H

#include <stdint.h>

#define ATOMIC_FLAG_INIT 0

#define ATOMIC_VAR_INIT(value) (value)

#define atomic_init(obj, value) \
do {                            \
    *(obj) = (value);           \
} while(0)

#define kill_dependency(y) ((void)0)

#define atomic_signal_fence(order) \
    ((void)0)

#define atomic_is_lock_free(obj) 0

typedef intptr_t atomic_flag;
typedef intptr_t atomic_bool;
typedef intptr_t atomic_char;
typedef intptr_t atomic_schar;
typedef intptr_t atomic_uchar;
typedef intptr_t atomic_short;
typedef intptr_t atomic_ushort;
typedef intptr_t atomic_int;
typedef intptr_t atomic_uint;
typedef intptr_t atomic_long;
typedef intptr_t atomic_ulong;
typedef intptr_t atomic_llong;
typedef intptr_t atomic_ullong;
typedef intptr_t atomic_wchar_t;
typedef intptr_t atomic_int_least8_t;
typedef intptr_t atomic_uint_least8_t;
typedef intptr_t atomic_int_least16_t;
typedef intptr_t atomic_uint_least16_t;
typedef intptr_t atomic_int_least32_t;
typedef intptr_t atomic_uint_least32_t;
typedef intptr_t atomic_int_least64_t;
typedef intptr_t atomic_uint_least64_t;
typedef intptr_t atomic_int_fast8_t;
typedef intptr_t atomic_uint_fast8_t;
typedef intptr_t atomic_int_fast16_t;
typedef intptr_t atomic_uint_fast16_t;
typedef intptr_t atomic_int_fast32_t;
typedef intptr_t atomic_uint_fast32_t;
typedef intptr_t atomic_int_fast64_t;
typedef intptr_t atomic_uint_fast64_t;
typedef intptr_t atomic_intptr_t;
typedef intptr_t atomic_uintptr_t;
typedef intptr_t atomic_size_t;
typedef intptr_t atomic_ptrdiff_t;
typedef intptr_t atomic_intmax_t;
typedef intptr_t atomic_uintmax_t;

void avpriv_atomic_lock(void);
void avpriv_atomic_unlock(void);

static inline void atomic_thread_fence(int order)
{
    avpriv_atomic_lock();
    avpriv_atomic_unlock();
}

static inline void atomic_store(intptr_t *object, intptr_t desired)
{
    avpriv_atomic_lock();
    *object = desired;
    avpriv_atomic_unlock();
}

#define atomic_store_explicit(object, desired, order) \
    atomic_store(object, desired)

static inline intptr_t atomic_load(intptr_t *object)
{
    intptr_t ret;
    avpriv_atomic_lock();
    ret = *object;
    avpriv_atomic_unlock();
    return ret;
}

#define atomic_load_explicit(object, order) \
    atomic_load(object)

static inline intptr_t atomic_exchange(intptr_t *object, intptr_t desired)
{
    intptr_t ret;
    avpriv_atomic_lock();
    ret     = *object;
    *object = desired;
    avpriv_atomic_unlock();
    return ret;
}

#define atomic_exchange_explicit(object, desired, order) \
    atomic_exchange(object, desired)

static inline int atomic_compare_exchange_strong(intptr_t *object, intptr_t *expected,
                                                 intptr_t desired)
{
    int ret;
    avpriv_atomic_lock();
    if (*object == *expected) {
        ret     = 1;
        *object = desired;
    } else {
        ret = 0;
        *expected = *object;
    }
    avpriv_atomic_unlock();
    return ret;
}

#define atomic_compare_exchange_strong_explicit(object, expected, desired, success, failure) \
    atomic_compare_exchange_strong(object, expected, desired)

#define atomic_compare_exchange_weak(object, expected, desired) \
    atomic_compare_exchange_strong(object, expected, desired)

#define atomic_compare_exchange_weak_explicit(object, expected, desired, success, failure) \
    atomic_compare_exchange_weak(object, expected, desired)

#define FETCH_MODIFY(opname, op)                                                   \
static inline intptr_t atomic_fetch_ ## opname(intptr_t *object, intptr_t operand) \
{                                                                                  \
    intptr_t ret;                                                                  \
    avpriv_atomic_lock();                                                          \
    ret = *object;                                                                 \
    *object = *object op operand;                                                  \
    avpriv_atomic_unlock();                                                        \
    return ret;                                                                    \
}

FETCH_MODIFY(add, +)
FETCH_MODIFY(sub, -)
FETCH_MODIFY(or,  |)
FETCH_MODIFY(xor, ^)
FETCH_MODIFY(and, &)

#undef FETCH_MODIFY

#define atomic_fetch_add_explicit(object, operand, order) \
    atomic_fetch_add(object, operand)

#define atomic_fetch_sub_explicit(object, operand, order) \
    atomic_fetch_sub(object, operand)

#define atomic_fetch_or_explicit(object, operand, order) \
    atomic_fetch_or(object, operand)

#define atomic_fetch_xor_explicit(object, operand, order) \
    atomic_fetch_xor(object, operand)

#define atomic_fetch_and_explicit(object, operand, order) \
    atomic_fetch_and(object, operand)

#define atomic_flag_test_and_set(object) \
    atomic_exchange(object, 1)

#define atomic_flag_test_and_set_explicit(object, order) \
    atomic_flag_test_and_set(object)

#define atomic_flag_clear(object) \
    atomic_store(object, 0)

#define atomic_flag_clear_explicit(object, order) \
    atomic_flag_clear(object)

#endif /* COMPAT_ATOMICS_PTHREAD_STDATOMIC_H */