circuitpython/supervisor/shared/fatfs.c

/*
 * This file is part of the MicroPython project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2022 Scott Shawcroft for Adafruit Industries
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "supervisor/fatfs.h"

#include "py/runtime.h"
#include "lib/oofatfs/ff.h"
#include "shared-bindings/microcontroller/Processor.h"
#include "shared-bindings/os/__init__.h"
#include "shared-bindings/rtc/RTC.h"
#include "shared-bindings/time/__init__.h"
#include "shared/timeutils/timeutils.h"

DWORD _time_override = 0;
DWORD get_fattime(void) {
    if (_time_override > 0) {
        return _time_override;
    }
    #if CIRCUITPY_RTC
    timeutils_struct_time_t tm;
    common_hal_rtc_get_time(&tm);
    return ((tm.tm_year - 1980) << 25) | (tm.tm_mon << 21) | (tm.tm_mday << 16) |
           (tm.tm_hour << 11) | (tm.tm_min << 5) | (tm.tm_sec >> 1);
    #else
    return ((2016 - 1980) << 25) | ((9) << 21) | ((1) << 16) | ((16) << 11) | ((43) << 5) | (35 / 2);
    #endif
}

void override_fattime(DWORD time) {
    _time_override = time;
}

DWORD make_volid(void) {
    DWORD result;
    if (!common_hal_os_urandom((uint8_t *)&result, sizeof(result))) {
        #if CIRCUITPY_MICROCONTROLLER && COMMON_HAL_MCU_PROCESSOR_UID_LENGTH >= 4
        uint8_t raw_id[COMMON_HAL_MCU_PROCESSOR_UID_LENGTH];
        common_hal_mcu_processor_get_uid(raw_id);
        memcpy(&result, raw_id, sizeof(result));
        #else
        result = (DWORD)common_hal_time_monotonic_ns();
        #endif
    }
    return result;
}