/* SPDX-License-Identifier: MPL-2.0 */

#include "precompiled.hpp"

#include <stdlib.h>

#if !defined ZMQ_HAVE_WINDOWS

#include <unistd.h>

#endif

#include "random.hpp"

#include "stdint.hpp"

#include "clock.hpp"

#include "mutex.hpp"

#include "macros.hpp"

#if defined(ZMQ_USE_LIBSODIUM)

#include "sodium.h"

#endif

void zmq::seed_random ()

{

#if defined ZMQ_HAVE_WINDOWS

    const int pid = static_cast<int> (GetCurrentProcessId ());

#else

    int pid = static_cast<int> (getpid ());

#endif

    srand (static_cast<unsigned int> (clock_t::now_us () + pid));

}

uint32_t zmq::generate_random ()

{

    //  Compensate for the fact that rand() returns signed integer.

    const uint32_t low = static_cast<uint32_t> (rand ());

    uint32_t high = static_cast<uint32_t> (rand ());

    high <<= (sizeof (int) * 8 - 1);

    return high | low;

}

static void manage_random (bool init_)

{

#if defined(ZMQ_USE_LIBSODIUM)

    if (init_) {

        //  sodium_init() is now documented as thread-safe in recent versions

        int rc = sodium_init ();

        zmq_assert (rc != -1);

#if defined(ZMQ_LIBSODIUM_RANDOMBYTES_CLOSE)

    } else {

        // randombytes_close either a no-op or not threadsafe

        // doing this without refcounting can cause crashes

        // if called while a context is active

        randombytes_close ();

#endif

    }

#else

    LIBZMQ_UNUSED (init_);

#endif

}

void zmq::random_open ()

{

    manage_random (true);

}

void zmq::random_close ()

{

    manage_random (false);

}