shithub: lwext4

ref: 49363e93477e3a0065dbc73da9b383a8e52aefe3
dir: /blockdev/filedev_win/io_raw.c/

/*
 * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <ext4_config.h>
#include <ext4_blockdev.h>
#include <ext4_errno.h>
#include <stdio.h>
#include <stdbool.h>
#include <string.h>

#ifdef WIN32
#include <windows.h>
#include <winioctl.h>


/**@brief   Default filename.*/
static const char *fname = "ext2";

/**@brief   IO block size.*/
#define EXT4_IORAW_BSIZE      512

/**@brief   Image file descriptor.*/
static HANDLE dev_file;


/**********************BLOCKDEV INTERFACE**************************************/
static int io_raw_open(struct ext4_blockdev *bdev);
static int io_raw_bread(struct ext4_blockdev *bdev, void *buf, uint64_t blk_id,
    uint32_t blk_cnt);
static int io_raw_bwrite(struct ext4_blockdev *bdev, const void *buf,
    uint64_t blk_id, uint32_t blk_cnt);
static int io_raw_close(struct  ext4_blockdev *bdev);




/******************************************************************************/
EXT4_BLOCKDEV_STATIC_INSTANCE(
    _filedev,
    EXT4_IORAW_BSIZE,
    0,
    io_raw_open,
    io_raw_bread,
    io_raw_bwrite,
    io_raw_close
);

/******************************************************************************/
static int io_raw_open(struct ext4_blockdev *bdev)
{
    char path[64];
    DISK_GEOMETRY   pdg;
    uint64_t disk_size;
    BOOL bResult   = FALSE;
    DWORD junk;

    sprintf(path, "\\\\.\\%s", fname);

    dev_file = CreateFile (path,
            GENERIC_READ | GENERIC_WRITE,
            FILE_SHARE_WRITE | FILE_SHARE_READ,
            NULL,
            OPEN_EXISTING,
            FILE_FLAG_NO_BUFFERING | FILE_FLAG_WRITE_THROUGH,
            NULL);

    if (dev_file == INVALID_HANDLE_VALUE){
        return EIO;
    }

    bResult = DeviceIoControl(dev_file,
            IOCTL_DISK_GET_DRIVE_GEOMETRY,
            NULL, 0,
            &pdg, sizeof(pdg),
            &junk,
            (LPOVERLAPPED) NULL);

    if(bResult == FALSE){
        CloseHandle(dev_file);
        return EIO;
    }


    disk_size = pdg.Cylinders.QuadPart * (ULONG)pdg.TracksPerCylinder *
            (ULONG)pdg.SectorsPerTrack * (ULONG)pdg.BytesPerSector;

    _filedev.ph_bsize = pdg.BytesPerSector;
    _filedev.ph_bcnt  = disk_size / pdg.BytesPerSector;


    return EOK;
}

/******************************************************************************/

static int io_raw_bread(struct  ext4_blockdev *bdev, void *buf, uint64_t blk_id,
    uint32_t blk_cnt)
{
    long hipart = blk_id >> (32-9);
    long lopart = blk_id << 9;
    long err;

    SetLastError (0);
    lopart = SetFilePointer (dev_file, lopart, &hipart, FILE_BEGIN);

    if (lopart == -1  &&  NO_ERROR != (err = GetLastError ()))
    {
        return EIO;
    }

    DWORD   n;

    if (!ReadFile (dev_file, buf, blk_cnt * 512, &n, NULL))
    {
        err = GetLastError ();
        return EIO;
    }
    return EOK;
}

/******************************************************************************/
static int io_raw_bwrite(struct ext4_blockdev *bdev, const void *buf,
    uint64_t blk_id, uint32_t blk_cnt)
{
    long hipart = blk_id >> (32-9);
    long lopart = blk_id << 9;
    long err;

    SetLastError (0);
    lopart = SetFilePointer (dev_file, lopart, &hipart, FILE_BEGIN);

    if (lopart == -1  &&  NO_ERROR != (err = GetLastError ()))
    {
        return EIO;
    }

    DWORD   n;

    if (!WriteFile (dev_file, buf, blk_cnt * 512, &n, NULL))
    {
        err = GetLastError ();
        return EIO;
    }
    return EOK;
}

/******************************************************************************/
static int io_raw_close(struct  ext4_blockdev *bdev)
{
    CloseHandle(dev_file);
    return EOK;
}

/******************************************************************************/
struct  ext4_blockdev* ext4_io_raw_dev_get(void)
{
    return &_filedev;
}
/******************************************************************************/
void ext4_io_raw_filename(const char *n)
{
    fname = n;
}

/******************************************************************************/
#endif