mbedtls/tests/suites/test_suite_platform.function

/* BEGIN_HEADER */

/* This test module exercises the platform_* module. Since, depending on the
 * underlying operating system, the time routines are not always reliable,
 * this suite only performs very basic sanity checks of the timing API.
 */

#include <limits.h>

#if defined(MBEDTLS_HAVE_TIME)
#include "mbedtls/platform_time.h"

#ifdef WIN32
#include <windows.h>
#elif _POSIX_C_SOURCE >= 199309L
#include <time.h>
#else
#include <unistd.h>
#endif
void sleep_ms(int milliseconds)
{
#ifdef WIN32
    Sleep(milliseconds);
#elif _POSIX_C_SOURCE >= 199309L
    struct timespec ts;
    ts.tv_sec = milliseconds / 1000;
    ts.tv_nsec = (milliseconds % 1000) * 1000000;
    nanosleep(&ts, NULL);
#else
    usleep(milliseconds * 1000);
#endif
}
#endif

/* END_HEADER */

/* BEGIN_DEPENDENCIES */

/* END_DEPENDENCIES */

/* BEGIN_CASE depends_on:MBEDTLS_HAVE_TIME */
void time_get_milliseconds()
{
    mbedtls_ms_time_t current = mbedtls_ms_time();
    (void) current;
    /* This goto is added to avoid warnings from the generated code. */
    goto exit;
}
/* END_CASE */

/* BEGIN_CASE depends_on:MBEDTLS_HAVE_TIME */
void time_get_seconds()
{
    mbedtls_time_t current = mbedtls_time(NULL);
    (void) current;
    /* This goto is added to avoid warnings from the generated code. */
    goto exit;
}
/* END_CASE */

/* BEGIN_CASE depends_on:MBEDTLS_HAVE_TIME */
void time_delay_milliseconds(int delay_ms)
{
    mbedtls_ms_time_t current = mbedtls_ms_time();
    mbedtls_ms_time_t elapsed_ms;

    sleep_ms(delay_ms);

    elapsed_ms = mbedtls_ms_time() - current;
    TEST_ASSERT(elapsed_ms >= delay_ms && elapsed_ms < 4000 + delay_ms);
    /* This goto is added to avoid warnings from the generated code. */
    goto exit;
}
/* END_CASE */

/* BEGIN_CASE depends_on:MBEDTLS_HAVE_TIME */

/*
 * WARNING: DO NOT ENABLE THIS TEST. We keep the code here to document the
 *          reason.
 *
 *          The test often failed on the CI. See #1517. CI failures cannot be
 *          completely avoided due to out-of-sync clock sources.
 */
void time_delay_seconds(int delay_secs)
{
    mbedtls_time_t current = mbedtls_time(NULL);
    mbedtls_time_t elapsed_secs;

    sleep_ms(delay_secs * 1000);

    elapsed_secs = mbedtls_time(NULL) - current;

    /*
     * `mbedtls_time()` was defined as c99 function `time()`, returns the number
     * of seconds since the Epoch. And it is affected by discontinuous changes
     * from automatic drift adjustment or time setting system call. The POSIX.1
     * specification for clock_settime says that discontinuous changes in
     * CLOCK_REALTIME should not affect `nanosleep()`.
     *
     * If discontinuous changes occur during `nanosleep()`, we will get
     * `elapsed_secs < delay_secs` for backward or `elapsed_secs > delay_secs`
     * for forward.
     *
     * The following tolerance windows cannot be guaranteed.
     * PLEASE DO NOT ENABLE IT IN CI TEST.
     */
    TEST_ASSERT(elapsed_secs - delay_secs >= -1 &&
                elapsed_secs - delay_secs <   4);
    /* This goto is added to avoid warnings from the generated code. */
    goto exit;
}
/* END_CASE */