/*

 * Copyright 2022-2023 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <openssl/crypto.h>

#include "internal/e_os.h"

/* system-specific variants defining OSSL_sleep() */

#if defined(OPENSSL_SYS_UNIX) || defined(__DJGPP__)

#include <unistd.h>

void OSSL_sleep(uint64_t millis)

{

# ifdef OPENSSL_SYS_VXWORKS

    struct timespec ts;

    ts.tv_sec = (long int) (millis / 1000);

    ts.tv_nsec = (long int) (millis % 1000) * 1000000ul;

    nanosleep(&ts, NULL);

# elif defined(__TANDEM)

#  if !defined(_REENTRANT)

#   include <cextdecs.h(PROCESS_DELAY_)>

    /* HPNS does not support usleep for non threaded apps */

    PROCESS_DELAY_(millis * 1000);

#  elif defined(_SPT_MODEL_)

#   include <spthread.h>

#   include <spt_extensions.h>

    usleep(millis * 1000);

#  else

    usleep(millis * 1000);

#  endif

# else

    unsigned int s = (unsigned int)(millis / 1000);

    unsigned int us = (unsigned int)((millis % 1000) * 1000);

    sleep(s);

    usleep(us);

# endif

}

#elif defined(_WIN32) && !defined(OPENSSL_SYS_UEFI)

# include <windows.h>

void OSSL_sleep(uint64_t millis)

{

    /*

     * Windows' Sleep() takes a DWORD argument, which is smaller than

     * a uint64_t, so we need to limit it to 49 days, which should be enough.

     */

    DWORD limited_millis = (DWORD)-1;

    if (millis < limited_millis)

        limited_millis = (DWORD)millis;

    Sleep(limited_millis);

}

#else

/* Fallback to a busy wait */

# include "internal/time.h"

static void ossl_sleep_secs(uint64_t secs)

{

    /*

     * sleep() takes an unsigned int argument, which is smaller than

     * a uint64_t, so it needs to be limited to 136 years which

     * should be enough even for Sleeping Beauty.

     */

    unsigned int limited_secs = UINT_MAX;

    if (secs < limited_secs)

        limited_secs = (unsigned int)secs;

    sleep(limited_secs);

}

static void ossl_sleep_millis(uint64_t millis)

{

    const OSSL_TIME finish

        = ossl_time_add(ossl_time_now(), ossl_ms2time(millis));

    while (ossl_time_compare(ossl_time_now(), finish) < 0)

        /* busy wait */ ;

}

void OSSL_sleep(uint64_t millis)

{

    ossl_sleep_secs(millis / 1000);

    ossl_sleep_millis(millis % 1000);

}

#endif /* defined(OPENSSL_SYS_UNIX) || defined(__DJGPP__) */