/*
 * Block driver for RAW files (win32)
 *
 * Copyright (c) 2006 Fabrice Bellard
 *
 * 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 "qemu-common.h"
#include "qemu-timer.h"
#include "block_int.h"
#include <assert.h>
#include <winioctl.h>

//#define WIN32_AIO

#define FTYPE_FILE 0
#define FTYPE_CD     1
#define FTYPE_HARDDISK 2

typedef struct BDRVRawState {
    HANDLE hfile;
    int type;
    char drive_path[16]; /* format: "d:\" */
} BDRVRawState;

typedef struct RawAIOCB {
    BlockDriverAIOCB common;
    HANDLE hEvent;
    OVERLAPPED ov;
    int count;
} RawAIOCB;

int qemu_ftruncate64(int fd, int64_t length)
{
    LARGE_INTEGER li;
    LONG high;
    HANDLE h;
    BOOL res;

    if ((GetVersion() & 0x80000000UL) && (length >> 32) != 0)
	return -1;

    h = (HANDLE)_get_osfhandle(fd);

    /* get current position, ftruncate do not change position */
    li.HighPart = 0;
    li.LowPart = SetFilePointer (h, 0, &li.HighPart, FILE_CURRENT);
    if (li.LowPart == 0xffffffffUL && GetLastError() != NO_ERROR)
	return -1;

    high = length >> 32;
    if (!SetFilePointer(h, (DWORD) length, &high, FILE_BEGIN))
	return -1;
    res = SetEndOfFile(h);

    /* back to old position */
    SetFilePointer(h, li.LowPart, &li.HighPart, FILE_BEGIN);
    return res ? 0 : -1;
}

static int set_sparse(int fd)
{
    DWORD returned;
    return (int) DeviceIoControl((HANDLE)_get_osfhandle(fd), FSCTL_SET_SPARSE,
				 NULL, 0, NULL, 0, &returned, NULL);
}

static int raw_open(BlockDriverState *bs, const char *filename, int flags)
{
    BDRVRawState *s = bs->opaque;
    int access_flags, create_flags;
    DWORD overlapped;

    s->type = FTYPE_FILE;

    if ((flags & BDRV_O_ACCESS) == O_RDWR) {
        access_flags = GENERIC_READ | GENERIC_WRITE;
    } else {
        access_flags = GENERIC_READ;
    }
    if (flags & BDRV_O_CREAT) {
        create_flags = CREATE_ALWAYS;
    } else {
        create_flags = OPEN_EXISTING;
    }
#ifdef WIN32_AIO
    overlapped = FILE_FLAG_OVERLAPPED;
#else
    overlapped = FILE_ATTRIBUTE_NORMAL;
#endif
    if ((flags & BDRV_O_NOCACHE))
        overlapped |= FILE_FLAG_NO_BUFFERING | FILE_FLAG_WRITE_THROUGH;
    else if (!(flags & BDRV_O_CACHE_WB))
        overlapped |= FILE_FLAG_WRITE_THROUGH;
    s->hfile = CreateFile(filename, access_flags,
                          FILE_SHARE_READ, NULL,
                          create_flags, overlapped, NULL);
    if (s->hfile == INVALID_HANDLE_VALUE) {
        int err = GetLastError();

        if (err == ERROR_ACCESS_DENIED)
            return -EACCES;
        return -1;
    }
    return 0;
}

static int raw_pread(BlockDriverState *bs, int64_t offset,
                     uint8_t *buf, int count)
{
    BDRVRawState *s = bs->opaque;
    OVERLAPPED ov;
    DWORD ret_count;
    int ret;

    memset(&ov, 0, sizeof(ov));
    ov.Offset = offset;
    ov.OffsetHigh = offset >> 32;
    ret = ReadFile(s->hfile, buf, count, &ret_count, &ov);
    if (!ret) {
#ifdef WIN32_AIO
        ret = GetOverlappedResult(s->hfile, &ov, &ret_count, TRUE);
        if (!ret)
            return -EIO;
        else
#endif
            return ret_count;
    }
    return ret_count;
}

static int raw_pwrite(BlockDriverState *bs, int64_t offset,
                      const uint8_t *buf, int count)
{
    BDRVRawState *s = bs->opaque;
    OVERLAPPED ov;
    DWORD ret_count;
    int ret;

    memset(&ov, 0, sizeof(ov));
    ov.Offset = offset;
    ov.OffsetHigh = offset >> 32;
    ret = WriteFile(s->hfile, buf, count, &ret_count, &ov);
    if (!ret) {
#ifdef WIN32_AIO
        ret = GetOverlappedResult(s->hfile, &ov, &ret_count, TRUE);
        if (!ret)
            return -EIO;
        else
#endif
            return ret_count;
    }
    return ret_count;
}

#ifdef WIN32_AIO
static void raw_aio_cb(void *opaque)
{
    RawAIOCB *acb = opaque;
    BlockDriverState *bs = acb->common.bs;
    BDRVRawState *s = bs->opaque;
    DWORD ret_count;
    int ret;

    ret = GetOverlappedResult(s->hfile, &acb->ov, &ret_count, TRUE);
    if (!ret || ret_count != acb->count) {
        acb->common.cb(acb->common.opaque, -EIO);
    } else {
        acb->common.cb(acb->common.opaque, 0);
    }
}

static RawAIOCB *raw_aio_setup(BlockDriverState *bs,
        int64_t sector_num, uint8_t *buf, int nb_sectors,
        BlockDriverCompletionFunc *cb, void *opaque)
{
    RawAIOCB *acb;
    int64_t offset;

    acb = qemu_aio_get(bs, cb, opaque);
    if (acb->hEvent) {
        acb->hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
        if (!acb->hEvent) {
            qemu_aio_release(acb);
            return NULL;
        }
    }
    memset(&acb->ov, 0, sizeof(acb->ov));
    offset = sector_num * 512;
    acb->ov.Offset = offset;
    acb->ov.OffsetHigh = offset >> 32;
    acb->ov.hEvent = acb->hEvent;
    acb->count = nb_sectors * 512;
    qemu_add_wait_object(acb->ov.hEvent, raw_aio_cb, acb);
    return acb;
}

static BlockDriverAIOCB *raw_aio_read(BlockDriverState *bs,
        int64_t sector_num, uint8_t *buf, int nb_sectors,
        BlockDriverCompletionFunc *cb, void *opaque)
{
    BDRVRawState *s = bs->opaque;
    RawAIOCB *acb;
    int ret;

    acb = raw_aio_setup(bs, sector_num, buf, nb_sectors, cb, opaque);
    if (!acb)
        return NULL;
    ret = ReadFile(s->hfile, buf, acb->count, NULL, &acb->ov);
    if (!ret) {
        qemu_aio_release(acb);
        return NULL;
    }
    qemu_aio_release(acb);
    return (BlockDriverAIOCB *)acb;
}

static BlockDriverAIOCB *raw_aio_write(BlockDriverState *bs,
        int64_t sector_num, uint8_t *buf, int nb_sectors,
        BlockDriverCompletionFunc *cb, void *opaque)
{
    BDRVRawState *s = bs->opaque;
    RawAIOCB *acb;
    int ret;

    acb = raw_aio_setup(bs, sector_num, buf, nb_sectors, cb, opaque);
    if (!acb)
        return NULL;
    ret = WriteFile(s->hfile, buf, acb->count, NULL, &acb->ov);
    if (!ret) {
        qemu_aio_release(acb);
        return NULL;
    }
    qemu_aio_release(acb);
    return (BlockDriverAIOCB *)acb;
}

static void raw_aio_cancel(BlockDriverAIOCB *blockacb)
{
    RawAIOCB *acb = (RawAIOCB *)blockacb;
    BlockDriverState *bs = acb->common.bs;
    BDRVRawState *s = bs->opaque;

    qemu_del_wait_object(acb->ov.hEvent, raw_aio_cb, acb);
    /* XXX: if more than one async I/O it is not correct */
    CancelIo(s->hfile);
    qemu_aio_release(acb);
}
#endif /* #if WIN32_AIO */

static void raw_flush(BlockDriverState *bs)
{
    BDRVRawState *s = bs->opaque;
    FlushFileBuffers(s->hfile);
}

static void raw_close(BlockDriverState *bs)
{
    BDRVRawState *s = bs->opaque;
    CloseHandle(s->hfile);
}

static int raw_truncate(BlockDriverState *bs, int64_t offset)
{
    BDRVRawState *s = bs->opaque;
    DWORD low, high;

    low = offset;
    high = offset >> 32;
    if (!SetFilePointer(s->hfile, low, &high, FILE_BEGIN))
	return -EIO;
    if (!SetEndOfFile(s->hfile))
        return -EIO;
    return 0;
}

static int64_t raw_getlength(BlockDriverState *bs)
{
    BDRVRawState *s = bs->opaque;
    LARGE_INTEGER l;
    ULARGE_INTEGER available, total, total_free;
    DISK_GEOMETRY_EX dg;
    DWORD count;
    BOOL status;

    switch(s->type) {
    case FTYPE_FILE:
        l.LowPart = GetFileSize(s->hfile, &l.HighPart);
        if (l.LowPart == 0xffffffffUL && GetLastError() != NO_ERROR)
            return -EIO;
        break;
    case FTYPE_CD:
        if (!GetDiskFreeSpaceEx(s->drive_path, &available, &total, &total_free))
            return -EIO;
        l.QuadPart = total.QuadPart;
        break;
    case FTYPE_HARDDISK:
        status = DeviceIoControl(s->hfile, IOCTL_DISK_GET_DRIVE_GEOMETRY_EX,
                                 NULL, 0, &dg, sizeof(dg), &count, NULL);
        if (status != 0) {
            l = dg.DiskSize;
        }
        break;
    default:
        return -EIO;
    }
    return l.QuadPart;
}

static int raw_create(const char *filename, int64_t total_size,
                      const char *backing_file, int flags)
{
    int fd;

    if (flags || backing_file)
        return -ENOTSUP;

    fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
              0644);
    if (fd < 0)
        return -EIO;
    set_sparse(fd);
    ftruncate(fd, total_size * 512);
    close(fd);
    return 0;
}

BlockDriver bdrv_raw = {
    "raw",
    sizeof(BDRVRawState),
    NULL, /* no probe for protocols */
    raw_open,
    NULL,
    NULL,
    raw_close,
    raw_create,
    raw_flush,

#ifdef WIN32_AIO
    .bdrv_aio_read = raw_aio_read,
    .bdrv_aio_write = raw_aio_write,
    .bdrv_aio_cancel = raw_aio_cancel,
    .aiocb_size = sizeof(RawAIOCB);
#endif
    .bdrv_pread = raw_pread,
    .bdrv_pwrite = raw_pwrite,
    .bdrv_truncate = raw_truncate,
    .bdrv_getlength = raw_getlength,
};

/***********************************************/
/* host device */

static int find_cdrom(char *cdrom_name, int cdrom_name_size)
{
    char drives[256], *pdrv = drives;
    UINT type;

    memset(drives, 0, sizeof(drives));
    GetLogicalDriveStrings(sizeof(drives), drives);
    while(pdrv[0] != '\0') {
        type = GetDriveType(pdrv);
        switch(type) {
        case DRIVE_CDROM:
            snprintf(cdrom_name, cdrom_name_size, "\\\\.\\%c:", pdrv[0]);
            return 0;
            break;
        }
        pdrv += lstrlen(pdrv) + 1;
    }
    return -1;
}

static int find_device_type(BlockDriverState *bs, const char *filename)
{
    BDRVRawState *s = bs->opaque;
    UINT type;
    const char *p;

    if (strstart(filename, "\\\\.\\", &p) ||
        strstart(filename, "//./", &p)) {
        if (stristart(p, "PhysicalDrive", NULL))
            return FTYPE_HARDDISK;
        snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", p[0]);
        type = GetDriveType(s->drive_path);
        if (type == DRIVE_CDROM)
            return FTYPE_CD;
        else
            return FTYPE_FILE;
    } else {
        return FTYPE_FILE;
    }
}

static int hdev_open(BlockDriverState *bs, const char *filename, int flags)
{
    BDRVRawState *s = bs->opaque;
    int access_flags, create_flags;
    DWORD overlapped;
    char device_name[64];

    if (strstart(filename, "/dev/cdrom", NULL)) {
        if (find_cdrom(device_name, sizeof(device_name)) < 0)
            return -ENOENT;
        filename = device_name;
    } else {
        /* transform drive letters into device name */
        if (((filename[0] >= 'a' && filename[0] <= 'z') ||
             (filename[0] >= 'A' && filename[0] <= 'Z')) &&
            filename[1] == ':' && filename[2] == '\0') {
            snprintf(device_name, sizeof(device_name), "\\\\.\\%c:", filename[0]);
            filename = device_name;
        }
    }
    s->type = find_device_type(bs, filename);

    if ((flags & BDRV_O_ACCESS) == O_RDWR) {
        access_flags = GENERIC_READ | GENERIC_WRITE;
    } else {
        access_flags = GENERIC_READ;
    }
    create_flags = OPEN_EXISTING;

#ifdef WIN32_AIO
    overlapped = FILE_FLAG_OVERLAPPED;
#else
    overlapped = FILE_ATTRIBUTE_NORMAL;
#endif
    if ((flags & BDRV_O_NOCACHE))
        overlapped |= FILE_FLAG_NO_BUFFERING | FILE_FLAG_WRITE_THROUGH;
    else if (!(flags & BDRV_O_CACHE_WB))
        overlapped |= FILE_FLAG_WRITE_THROUGH;
    s->hfile = CreateFile(filename, access_flags,
                          FILE_SHARE_READ, NULL,
                          create_flags, overlapped, NULL);
    if (s->hfile == INVALID_HANDLE_VALUE) {
        int err = GetLastError();

        if (err == ERROR_ACCESS_DENIED)
            return -EACCES;
        return -1;
    }
    return 0;
}

#if 0
/***********************************************/
/* removable device additional commands */

static int raw_is_inserted(BlockDriverState *bs)
{
    return 1;
}

static int raw_media_changed(BlockDriverState *bs)
{
    return -ENOTSUP;
}

static int raw_eject(BlockDriverState *bs, int eject_flag)
{
    DWORD ret_count;

    if (s->type == FTYPE_FILE)
        return -ENOTSUP;
    if (eject_flag) {
        DeviceIoControl(s->hfile, IOCTL_STORAGE_EJECT_MEDIA,
                        NULL, 0, NULL, 0, &lpBytesReturned, NULL);
    } else {
        DeviceIoControl(s->hfile, IOCTL_STORAGE_LOAD_MEDIA,
                        NULL, 0, NULL, 0, &lpBytesReturned, NULL);
    }
}

static int raw_set_locked(BlockDriverState *bs, int locked)
{
    return -ENOTSUP;
}
#endif

BlockDriver bdrv_host_device = {
    "host_device",
    sizeof(BDRVRawState),
    NULL, /* no probe for protocols */
    hdev_open,
    NULL,
    NULL,
    raw_close,
    NULL,
    raw_flush,

#ifdef WIN32_AIO
    .bdrv_aio_read = raw_aio_read,
    .bdrv_aio_write = raw_aio_write,
    .bdrv_aio_cancel = raw_aio_cancel,
    .aiocb_size = sizeof(RawAIOCB);
#endif
    .bdrv_pread = raw_pread,
    .bdrv_pwrite = raw_pwrite,
    .bdrv_getlength = raw_getlength,
};