FATFS 初学之 f_chmod/ f_utime

f_chmod：

/*-----------------------------------------------------------------------*/
/* Change Attribute                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_chmod (
    const TCHAR *path,    /* Pointer to the file path */
    BYTE value,            /* Attribute bits */
    BYTE mask            /* Attribute mask to change */
)
{
    FRESULT res;
    DIR dj;
    BYTE *dir;
    DEF_NAMEBUF;


    res = chk_mounted(&path, &dj.fs, 1);
    if (res == FR_OK) {
        INIT_BUF(dj);
        res = follow_path(&dj, path);        /* Follow the file path */
        FREE_BUF();
        if (_FS_RPATH && res == FR_OK && (dj.fn[NS] & NS_DOT))
            res = FR_INVALID_NAME;
        if (res == FR_OK) {
            dir = dj.dir;
            if (!dir) {                        /* Is it a root directory? */
                res = FR_INVALID_NAME;
            } else {                        /* File or sub directory */
                mask &= AM_RDO|AM_HID|AM_SYS|AM_ARC;    /* Valid attribute mask */
                dir[DIR_Attr] = (value & mask) | (dir[DIR_Attr] & (BYTE)~mask);    /* Apply attribute change */
                dj.fs->wflag = 1;
                res = sync(dj.fs);
            }
        }
    }

    LEAVE_FF(dj.fs, res);
}

函数功能：修改一个文件或目录的属性。

描述：

f_chmod函数当_FS_READONLY == 0并且_FS_MINIMIZE == 0时可用。
f_chmod函数修改一个文件或目录的属性。

f_utime：

/*-----------------------------------------------------------------------*/
/* Change Timestamp                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_utime (
    const TCHAR *path,    /* Pointer to the file/directory name */
    const FILINFO *fno    /* Pointer to the time stamp to be set */
)
{
    FRESULT res;
    DIR dj;
    BYTE *dir;
    DEF_NAMEBUF;


    res = chk_mounted(&path, &dj.fs, 1);
    if (res == FR_OK) {
        INIT_BUF(dj);
        res = follow_path(&dj, path);    /* Follow the file path */
        FREE_BUF();
        if (_FS_RPATH && res == FR_OK && (dj.fn[NS] & NS_DOT))
            res = FR_INVALID_NAME;
        if (res == FR_OK) {
            dir = dj.dir;
            if (!dir) {                    /* Root directory */
                res = FR_INVALID_NAME;
            } else {                    /* File or sub-directory */
                ST_WORD(dir+DIR_WrtTime, fno->ftime);
                ST_WORD(dir+DIR_WrtDate, fno->fdate);
                dj.fs->wflag = 1;
                res = sync(dj.fs);
            }
        }
    }

    LEAVE_FF(dj.fs, res);
}

函数功能：f_utime函数修改一个文件或目录的时间戳。

描述：

f_utime函数当_FS_READONLY == 0并且_FS_MINIMIZE == 0时可用。
f_utime函数修改一个文件或目录的时间戳(即文件属性里的创建、修改、访问时间)。

例：

// 设置只读标志，清除存档标志，其他不变
f_chmod("file.txt", AR_RDO, AR_RDO | AR_ARC);