/*
 * Copyright (C) 2020 Linux Studio Plugins Project <https://lsp-plug.in/>
 *           (C) 2020 Vladimir Sadovnikov <sadko4u@gmail.com>
 *
 * This file is part of lsp-common-lib
 * Created on: 31 мар. 2020 г.
 *
 * lsp-common-lib 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 3 of the License, or
 * any later version.
 *
 * lsp-common-lib 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 lsp-common-lib. If not, see <https://www.gnu.org/licenses/>.
 */

#ifndef LSP_PLUG_IN_COMMON_ATOMIC_H_
#define LSP_PLUG_IN_COMMON_ATOMIC_H_

#include <lsp-plug.in/common/version.h>
#include <lsp-plug.in/common/types.h>

/**
  Common atomic interface:

    Atomically swap the value 'value' with memory chunk pointed by
    'ptr' and return the previous value stored in memory chunk as 'ret':

        ret atomic_swap(*ptr, value)

    Atomicatlly add value 'value' to memory chunk pointed by 'ptr'
    and return the previous value stored in memory chunk as 'ret':

        ret atomic_add(*ptr, value)

    Atomically compare contents of memory chunk pointed by 'ptr'
    with expected value 'exp' and overwrite it with replacement 'rep'
    if they match. Return true on success, fail on error as 'ret'.

        ret atomic_cas(*ptr, exp, rep)
*/
namespace lsp
{
    typedef unsigned int    uatomic_t;
    typedef signed int      atomic_t;
}

#define LSP_PLUG_IN_COMMON_ATOMIC_IMPL
    #if defined(ARCH_X86) /* x86 and x86_64 implementation */
        #include <lsp-plug.in/common/arch/x86/atomic.h>
    #elif defined(ARCH_AARCH64) /* ARM 64-bit implementation */
        #include <lsp-plug.in/common/arch/aarch64/atomic.h>
    #elif defined(ARCH_ARM7) || defined(ARCH_ARM6) /* ARM 32-bit implementation */
        #include <lsp-plug.in/common/arch/arm/atomic.h>
    #elif defined(ARCH_ARM) /* ARM 32-bit implementation */
        #include <lsp-plug.in/common/arch/arm/atomic-legacy.h>
    #else /* Generic implementation */
        #include <lsp-plug.in/common/arch/generic/atomic.h>
    #endif /* ARCH_X86 */
#undef LSP_PLUG_IN_COMMON_ATOMIC_IMPL

namespace lsp
{
    // Common case
    template <class T>
    T *atomic_swap(T **ptr, T *value)
    {
        return static_cast<T *>(
            atomic_swap(
                reinterpret_cast<void **>(ptr),
                reinterpret_cast<void *>(value)
            )
        );
    }

    // Special case for NULL
    template <class T>
    T *atomic_swap(T **ptr, nullptr_t *value)
    {
        return static_cast<T *>(
            atomic_swap(
                reinterpret_cast<void **>(ptr),
                reinterpret_cast<void *>(value)
            )
        );
    }
} /* namespace lsp */

#endif /* LSP_PLUG_IN_COMMON_ATOMIC_H_ */
