/**********************************************************************
 *
 * Project:  CPL - Common Portability Library
 * Purpose:  Implement VSI large file api for Win32.
 * Author:   Frank Warmerdam, warmerdam@pobox.com
 *
 **********************************************************************
 * Copyright (c) 2000, Frank Warmerdam <warmerdam@pobox.com>
 * Copyright (c) 2008-2014, Even Rouault <even dot rouault at spatialys.com>
 *
 * 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 "cpl_vsi_virtual.h"

#if defined(WIN32)

#include <windows.h>
#include <winioctl.h>  // for FSCTL_SET_SPARSE

#include "cpl_string.h"

#include <sys/types.h>
#include <sys/stat.h>
#include <io.h>
#include <fcntl.h>
#include <direct.h>

/************************************************************************/
/* ==================================================================== */
/*                       VSIWin32FilesystemHandler                      */
/* ==================================================================== */
/************************************************************************/

// To avoid aliasing to GetDiskFreeSpace to GetDiskFreeSpaceA on Windows
#ifdef GetDiskFreeSpace
#undef GetDiskFreeSpace
#endif

class VSIWin32FilesystemHandler final : public VSIFilesystemHandler
{
    CPL_DISALLOW_COPY_ASSIGN(VSIWin32FilesystemHandler)

  public:
    // TODO(schwehr): Fix Open call to remove the need for this using call.
    using VSIFilesystemHandler::Open;

    VSIWin32FilesystemHandler() = default;

    virtual VSIVirtualHandle *Open(const char *pszFilename,
                                   const char *pszAccess, bool bSetError,
                                   CSLConstList /* papszOptions */) override;
    virtual int Stat(const char *pszFilename, VSIStatBufL *pStatBuf,
                     int nFlags) override;
    virtual int Unlink(const char *pszFilename) override;
    virtual int Rename(const char *oldpath, const char *newpath) override;
    virtual int Mkdir(const char *pszDirname, long nMode) override;
    virtual int Rmdir(const char *pszDirname) override;
    virtual char **ReadDirEx(const char *pszDirname, int nMaxFiles) override;
    virtual int IsCaseSensitive(const char *pszFilename) override
    {
        (void)pszFilename;
        return FALSE;
    }
    virtual GIntBig GetDiskFreeSpace(const char *pszDirname) override;
    virtual int SupportsSparseFiles(const char *pszPath) override;
    virtual bool IsLocal(const char *pszPath) override;
};

/************************************************************************/
/* ==================================================================== */
/*                            VSIWin32Handle                            */
/* ==================================================================== */
/************************************************************************/

class VSIWin32Handle final : public VSIVirtualHandle
{
    CPL_DISALLOW_COPY_ASSIGN(VSIWin32Handle)

  public:
    HANDLE hFile = nullptr;
    bool bEOF = false;

    VSIWin32Handle() = default;

    virtual int Seek(vsi_l_offset nOffset, int nWhence) override;
    virtual vsi_l_offset Tell() override;
    virtual size_t Read(void *pBuffer, size_t nSize, size_t nMemb) override;
    virtual size_t Write(const void *pBuffer, size_t nSize,
                         size_t nMemb) override;
    virtual int Eof() override;
    virtual int Flush() override;
    virtual int Close() override;
    virtual int Truncate(vsi_l_offset nNewSize) override;
    virtual void *GetNativeFileDescriptor() override
    {
        return static_cast<void *>(hFile);
    }
    virtual VSIRangeStatus GetRangeStatus(vsi_l_offset nOffset,
                                          vsi_l_offset nLength) override;
};

/************************************************************************/
/*                      ErrnoFromGetLastError()                         */
/*                                                                      */
/* Private function translating Windows API error codes to POSIX errno. */
/*                                                                      */
/* TODO: If the function is going to be public CPL function, then       */
/* replace the switch with array of (Win32 code, errno code) tuples and */
/* complement it with missing codes.                                    */
/************************************************************************/

static int ErrnoFromGetLastError(DWORD dwError = 0)
{
    int err = 0;
    if (dwError == 0)
        dwError = GetLastError();

    switch (dwError)
    {
        case NO_ERROR:
            err = 0;
            break;
        case ERROR_FILE_NOT_FOUND:       /* Cannot find the file specified. */
        case ERROR_PATH_NOT_FOUND:       /* Cannot find the path specified. */
        case ERROR_INVALID_DRIVE:        /* Cannot find the drive specified. */
        case ERROR_NO_MORE_FILES:        /* There are no more files. */
        case ERROR_BAD_PATHNAME:         /* The specified path is invalid. */
        case ERROR_BAD_NETPATH:          /* The network path was not found. */
        case ERROR_FILENAME_EXCED_RANGE: /* The filename or extension is too
                                            long. */
            err = ENOENT;
            break;
        case ERROR_TOO_MANY_OPEN_FILES: /* The system cannot open the file. */
            err = EMFILE;
            break;
        case ERROR_ACCESS_DENIED:     /* Access denied. */
        case ERROR_CURRENT_DIRECTORY: /* The directory cannot be removed. */
        case ERROR_WRITE_PROTECT:     /* The media is write protected. */
        case ERROR_LOCK_VIOLATION:    /* Another process has locked a portion of
                                         the file. */
        case ERROR_WRONG_DISK:        /* The wrong diskette is in the drive. */
        case ERROR_SHARING_BUFFER_EXCEEDED: /* Too many files opened for
                                               sharing. */
        case ERROR_DRIVE_LOCKED:      /* The disk is in use or locked by another
                                         process. */
        case ERROR_LOCK_FAILED:       /* Unable to lock a region of a file. */
        case ERROR_SEEK_ON_DEVICE:    /* The file pointer cannot be set on the
                                         specified device or file. */
        case ERROR_SHARING_VIOLATION: /* The process cannot access the file
                                         because it is being used by another
                                         process. */
            err = EACCES;
            break;
        case ERROR_INVALID_HANDLE:        /* The handle is invalid. */
        case ERROR_INVALID_TARGET_HANDLE: /* The target internal file identifier
                                             is incorrect. */
        case ERROR_DIRECT_ACCESS_HANDLE:  /* Operation other than raw disk I/O
                                             not permitted. */
            err = EBADF;
            break;
        case ERROR_ARENA_TRASHED: /* The storage control blocks were destroyed.
                                   */
        case ERROR_NOT_ENOUGH_MEMORY: /* Not enough storage is available. */
        case ERROR_INVALID_BLOCK:     /* The storage control block address is
                                         invalid. */
        case ERROR_NOT_ENOUGH_QUOTA: /* Not enough quota is available to process
                                        this command. */
            err = ENOMEM;
            break;
        case ERROR_BAD_ENVIRONMENT: /* The environment is incorrect. */
            err = E2BIG;
            break;
        case ERROR_INVALID_ACCESS: /* The access code is invalid. */
        case ERROR_INVALID_DATA:   /* The data is invalid. */
            err = EINVAL;
            break;
        case ERROR_NOT_SAME_DEVICE: /* The system cannot move the file to a
                                       different disk drive. */
            err = EXDEV;
            break;
        case ERROR_DIR_NOT_EMPTY: /* The directory is not empty. */
            err = ENOTEMPTY;
            break;
        case ERROR_FILE_EXISTS:    /* The file exists. */
        case ERROR_ALREADY_EXISTS: /* Cannot create a file when that file
                                      already exists. */
            err = EEXIST;
            break;
        case ERROR_DISK_FULL: /* There is not enough space on the disk. */
            err = ENOSPC;
            break;
        case ERROR_HANDLE_EOF: /* Reached the end of the file. */
            err = 0;           /* There is no errno equivalent in the errno.h */
            break;
        default:
            err = 0;
    }
    CPLAssert(0 <= err);

    return err;
}

/************************************************************************/
/*                               Close()                                */
/************************************************************************/

int VSIWin32Handle::Close()

{
    return CloseHandle(hFile) ? 0 : -1;
}

/************************************************************************/
/*                                Seek()                                */
/************************************************************************/

int VSIWin32Handle::Seek(vsi_l_offset nOffset, int nWhence)

{
    LONG dwMoveMethod, dwMoveHigh;
    GUInt32 nMoveLow;
    LARGE_INTEGER li;

    bEOF = false;

    switch (nWhence)
    {
        case SEEK_CUR:
            dwMoveMethod = FILE_CURRENT;
            break;
        case SEEK_END:
            dwMoveMethod = FILE_END;
            break;
        case SEEK_SET:
        default:
            dwMoveMethod = FILE_BEGIN;
            break;
    }

    li.QuadPart = nOffset;
    nMoveLow = li.LowPart;
    dwMoveHigh = li.HighPart;

    SetLastError(0);
    SetFilePointer(hFile, nMoveLow, &dwMoveHigh, dwMoveMethod);

    if (GetLastError() != NO_ERROR)
    {
#ifdef notdef
        LPVOID lpMsgBuf = nullptr;

        FormatMessage(
            FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM |
                FORMAT_MESSAGE_IGNORE_INSERTS,
            nullptr, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
            (LPTSTR)&lpMsgBuf, 0, nullptr);

        printf("[ERROR %d]\n %s\n", GetLastError(), (char *)lpMsgBuf); /*ok*/
        printf("nOffset=%u, nMoveLow=%u, dwMoveHigh=%u\n",             /*ok*/
               static_cast<GUInt32>(nOffset), nMoveLow, dwMoveHigh);
#endif
        errno = ErrnoFromGetLastError();
        return -1;
    }
    else
        return 0;
}

/************************************************************************/
/*                                Tell()                                */
/************************************************************************/

vsi_l_offset VSIWin32Handle::Tell()

{
    LARGE_INTEGER li;

    li.HighPart = 0;
    li.LowPart = SetFilePointer(hFile, 0, &(li.HighPart), FILE_CURRENT);

    return (static_cast<vsi_l_offset>(li.QuadPart));
}

/************************************************************************/
/*                               Flush()                                */
/************************************************************************/

int VSIWin32Handle::Flush()

{
    /* Nothing needed to offer the same guarantee as POSIX fflush() */
    /* FlushFileBuffers() would be closer to fsync() */
    /* See http://trac.osgeo.org/gdal/ticket/5556 */

    // Add this as a hack to make ogr_mitab_30 and _31 tests pass
    if (CPLTestBool(CPLGetConfigOption("VSI_FLUSH", "FALSE")))
        FlushFileBuffers(hFile);
    return 0;
}

/************************************************************************/
/*                                Read()                                */
/************************************************************************/

size_t VSIWin32Handle::Read(void *pBuffer, size_t nSize, size_t nCount)

{
    DWORD dwSizeRead = 0;
    size_t nResult = 0;

    if (!ReadFile(hFile, pBuffer, static_cast<DWORD>(nSize * nCount),
                  &dwSizeRead, nullptr))
    {
        nResult = 0;
        errno = ErrnoFromGetLastError();
    }
    else if (nSize == 0)
        nResult = 0;
    else
        nResult = dwSizeRead / nSize;

    if (nResult != nCount)
        bEOF = true;

    return nResult;
}

/************************************************************************/
/*                               Write()                                */
/************************************************************************/

size_t VSIWin32Handle::Write(const void *pBuffer, size_t nSize, size_t nCount)

{
    DWORD dwSizeWritten = 0;
    size_t nResult = 0;

    if (!WriteFile(hFile, pBuffer, static_cast<DWORD>(nSize * nCount),
                   &dwSizeWritten, nullptr))
    {
        nResult = 0;
        errno = ErrnoFromGetLastError();
    }
    else if (nSize == 0)
        nResult = 0;
    else
        nResult = dwSizeWritten / nSize;

    return nResult;
}

/************************************************************************/
/*                                Eof()                                 */
/************************************************************************/

int VSIWin32Handle::Eof()

{
    return bEOF;
}

/************************************************************************/
/*                             Truncate()                               */
/************************************************************************/

int VSIWin32Handle::Truncate(vsi_l_offset nNewSize)
{
    vsi_l_offset nCur = Tell();
    Seek(0, SEEK_END);
    if (nNewSize > Tell())
    {
        // Enable sparse files if growing size
        DWORD dwTemp;
        DeviceIoControl(hFile, FSCTL_SET_SPARSE, nullptr, 0, nullptr, 0,
                        &dwTemp, nullptr);
    }
    Seek(nNewSize, SEEK_SET);
    BOOL bRes = SetEndOfFile(hFile);
    Seek(nCur, SEEK_SET);

    if (bRes)
        return 0;
    else
        return -1;
}

/************************************************************************/
/*                           GetRangeStatus()                           */
/************************************************************************/

VSIRangeStatus VSIWin32Handle::GetRangeStatus(vsi_l_offset
#ifdef FSCTL_QUERY_ALLOCATED_RANGES
                                                  nOffset
#endif
                                              ,
                                              vsi_l_offset
#ifdef FSCTL_QUERY_ALLOCATED_RANGES
                                                  nLength
#endif
)
{
    // Not available on mingw includes
#ifdef FSCTL_QUERY_ALLOCATED_RANGES
    FILE_ALLOCATED_RANGE_BUFFER sQueryRange;
    FILE_ALLOCATED_RANGE_BUFFER asOutputRange[1];
    DWORD nOutputBytes = 0;

    sQueryRange.FileOffset.QuadPart = nOffset;
    sQueryRange.Length.QuadPart = nOffset + nLength;

    if (!DeviceIoControl(hFile, FSCTL_QUERY_ALLOCATED_RANGES, &sQueryRange,
                         sizeof(sQueryRange), asOutputRange,
                         sizeof(asOutputRange), &nOutputBytes, nullptr))
    {
        if (GetLastError() == ERROR_MORE_DATA)
        {
            return VSI_RANGE_STATUS_DATA;
        }
        else
        {
            return VSI_RANGE_STATUS_UNKNOWN;
        }
    }

    if (nOutputBytes)
        return VSI_RANGE_STATUS_DATA;
    else
        return VSI_RANGE_STATUS_HOLE;
#else
    return VSI_RANGE_STATUS_UNKNOWN;
#endif
}

/************************************************************************/
/* ==================================================================== */
/*                       VSIWin32FilesystemHandler                      */
/* ==================================================================== */
/************************************************************************/

/************************************************************************/
/*                          CPLGetWineVersion()                         */
/************************************************************************/

const char *CPLGetWineVersion();  // also used by cpl_aws.cpp

const char *CPLGetWineVersion()
{
    HMODULE hntdll = GetModuleHandle("ntdll.dll");
    if (hntdll == nullptr)
    {
        CPLDebug("CPLGetWineVersion", "Can't get handle to ntdll.dll.");
        return nullptr;
    }

    const char *(CDECL * pwine_get_version)(void);
    const auto ret = GetProcAddress(hntdll, "wine_get_version");
    static_assert(sizeof(pwine_get_version) == sizeof(ret),
                  "sizeof(pwine_get_version) == sizeof(ret)");
    memcpy(&pwine_get_version, &ret, sizeof(ret));
    if (pwine_get_version == nullptr)
    {
        return nullptr;
    }

    return pwine_get_version();
}

/************************************************************************/
/*                           VSIWin32StrlenW()                          */
/************************************************************************/

static size_t VSIWin32StrlenW(const wchar_t *pwszString)
{
    size_t nLen = 0;
    while (pwszString[nLen] != 0)
        nLen++;
    return nLen;
}

/************************************************************************/
/*                        VSIWin32TryLongFilename()                     */
/************************************************************************/

static void VSIWin32TryLongFilename(wchar_t *&pwszFilename)
{
    size_t nLen = VSIWin32StrlenW(pwszFilename);
    if (pwszFilename[0] != 0 && pwszFilename[1] == ':' &&
        (pwszFilename[2] == '\\' || pwszFilename[2] == '/'))
    {
        pwszFilename = static_cast<wchar_t *>(
            CPLRealloc(pwszFilename, (4 + nLen + 1) * sizeof(wchar_t)));
        memmove(pwszFilename + 4, pwszFilename, (nLen + 1) * sizeof(wchar_t));
    }
    else
    {
        // TODO(schwehr): 32768 should be a symbolic constant.
        wchar_t *pwszCurDir =
            static_cast<wchar_t *>(CPLMalloc(32768 * sizeof(wchar_t)));
        DWORD nCurDirLen = GetCurrentDirectoryW(32768, pwszCurDir);
        CPLAssert(nCurDirLen < 32768);
        pwszFilename = static_cast<wchar_t *>(CPLRealloc(
            pwszFilename, (4 + nCurDirLen + 1 + nLen + 1) * sizeof(wchar_t)));
        int nOffset = 0;
        if (pwszFilename[0] == '.' &&
            (pwszFilename[1] == '/' || pwszFilename[1] == '\\'))
            nOffset = 2;
        /* \\$\c:\a\b ..\c --> \\$\c:\a\c */
        while (pwszFilename[nOffset + 0] == '.' &&
               pwszFilename[nOffset + 1] == '.' &&
               (pwszFilename[nOffset + 2] == '/' ||
                pwszFilename[nOffset + 2] == '\\'))
        {
            DWORD nCurDirLenBefore = nCurDirLen;
            while (nCurDirLen > 0 && pwszCurDir[nCurDirLen - 1] != '\\')
                nCurDirLen--;
            if (nCurDirLen <= 2)
            {
                nCurDirLen = nCurDirLenBefore;
                break;
            }
            nCurDirLen--;
            nOffset += 3;
        }
        memmove(pwszFilename + 4 + nCurDirLen + 1, pwszFilename + nOffset,
                (nLen - nOffset + 1) * sizeof(wchar_t));
        memmove(pwszFilename + 4, pwszCurDir, nCurDirLen * sizeof(wchar_t));
        pwszFilename[4 + nCurDirLen] = '\\';
        CPLFree(pwszCurDir);
    }
    pwszFilename[0] = '\\';
    pwszFilename[1] = '\\';
    pwszFilename[2] = '?';
    pwszFilename[3] = '\\';

    for (size_t i = 4; pwszFilename[i] != 0; i++)
    {
        if (pwszFilename[i] == '/')
            pwszFilename[i] = '\\';
    }
#if notdef
    CPLString osFilename;
    for (size_t i = 0; pwszFilename[i] != 0; i++)
        osFilename += (char)pwszFilename[i];
    CPLDebug("VSI", "Trying %s", osFilename.c_str());
#endif
}

/************************************************************************/
/*                         VSIWin32IsLongFilename()                     */
/************************************************************************/

static bool VSIWin32IsLongFilename(const wchar_t *pwszFilename)
{
    return (pwszFilename[0] == '\\' && pwszFilename[1] == '\\' &&
            pwszFilename[2] == '?' && pwszFilename[3] == '\\');
}

/************************************************************************/
/*                                Open()                                */
/************************************************************************/

VSIVirtualHandle *
VSIWin32FilesystemHandler::Open(const char *pszFilename, const char *pszAccess,
                                bool bSetError, CSLConstList /* papszOptions */)

{
    DWORD dwDesiredAccess;
    DWORD dwCreationDisposition;
    DWORD dwFlagsAndAttributes;
    HANDLE hFile;

    // GENERICs are used instead of FILE_GENERIC_READ.
    dwDesiredAccess = GENERIC_READ;
    if (strchr(pszAccess, '+') != nullptr || strchr(pszAccess, 'w') != nullptr)
        dwDesiredAccess |= GENERIC_WRITE;

    // Append mode only makes sense on files and pipes, have to use FILE_ access
    // these are very different from the GENERICs
    // Append is read and write but not overwrite data (only append data)
    if (strchr(pszAccess, 'a') != nullptr)
    {
        dwDesiredAccess =
            FILE_GENERIC_READ | (FILE_GENERIC_WRITE ^ FILE_WRITE_DATA);

        // Wine < 1.7.4 doesn't work properly without FILE_WRITE_DATA bit
        // (it refuses to write at all), so we'd better re-add it even if the
        // resulting semantics isn't completely conformant.
        // See https://bugs.winehq.org/show_bug.cgi?id=33232
        const char *pszWineVersion = CPLGetWineVersion();
        if (pszWineVersion != nullptr)
        {
            int nVersion = atoi(pszWineVersion) * 10000;
            const char *pszDot = strchr(pszWineVersion, '.');
            if (pszDot)
            {
                nVersion += atoi(pszDot + 1) * 100;
                pszDot = strchr(pszDot + 1, '.');
                if (pszDot)
                {
                    nVersion += atoi(pszDot + 1);
                }
            }
            if (nVersion < 1 * 10000 + 7 * 100 + 4)
            {
#if DEBUG_VERBOSE
                CPLDebug("VSI",
                         "Wine %s detected. Append mode needs FILE_WRITE_DATA",
                         pszWineVersion);
#endif
                dwDesiredAccess |= FILE_WRITE_DATA;
            }
        }
    }

    if (strstr(pszAccess, "w") != nullptr)
        dwCreationDisposition = CREATE_ALWAYS;
    else if (strstr(pszAccess, "a") != nullptr)
        dwCreationDisposition = OPEN_ALWAYS;
    else
        dwCreationDisposition = OPEN_EXISTING;

    dwFlagsAndAttributes = (dwDesiredAccess == GENERIC_READ)
                               ? FILE_ATTRIBUTE_READONLY
                               : FILE_ATTRIBUTE_NORMAL;

    /* -------------------------------------------------------------------- */
    /*      On Win32 consider treating the filename as utf-8 and            */
    /*      converting to wide characters to open.                          */
    /* -------------------------------------------------------------------- */
    DWORD nLastError = 0;
    bool bShared = CPLTestBool(CPLGetConfigOption("GDAL_SHARED_FILE", "YES"));
    if (CPLTestBool(CPLGetConfigOption("GDAL_FILENAME_IS_UTF8", "YES")))
    {
        wchar_t *pwszFilename =
            CPLRecodeToWChar(pszFilename, CPL_ENC_UTF8, CPL_ENC_UCS2);

        hFile = CreateFileW(pwszFilename, dwDesiredAccess,
                            bShared ? FILE_SHARE_READ | FILE_SHARE_WRITE : 0,
                            nullptr, dwCreationDisposition,
                            dwFlagsAndAttributes, nullptr);
        if (hFile == INVALID_HANDLE_VALUE &&
            !VSIWin32IsLongFilename(pwszFilename))
        {
            nLastError = GetLastError();
#ifdef notdef
            switch (nLastError)
            {
                case ERROR_FILE_NOT_FOUND:
                    CPLDebug("VSI", "ERROR_FILE_NOT_FOUND");
                    break;
                case ERROR_PATH_NOT_FOUND:
                    CPLDebug("VSI", "ERROR_PATH_NOT_FOUND");
                    break;
                case ERROR_INVALID_DRIVE:
                    CPLDebug("VSI", "ERROR_INVALID_DRIVE");
                    break;
                case ERROR_NO_MORE_FILES:
                    CPLDebug("VSI", "ERROR_NO_MORE_FILES");
                    break;
                case ERROR_BAD_PATHNAME:
                    CPLDebug("VSI", "ERROR_BAD_PATHNAME");
                    break;
                case ERROR_BAD_NETPATH:
                    CPLDebug("VSI", "ERROR_BAD_NETPATH");
                    break;
                case ERROR_FILENAME_EXCED_RANGE:
                    CPLDebug("VSI", "ERROR_FILENAME_EXCED_RANGE");
                    break;
                case ERROR_SHARING_VIOLATION:
                    CPLDebug("VSI", "ERROR_SHARING_VIOLATION");
                    break;
                default:
                    CPLDebug("VSI", "other error %d", nLastError);
                    break;
            }
#endif
        }
        if (nLastError == ERROR_PATH_NOT_FOUND ||
            nLastError == ERROR_FILENAME_EXCED_RANGE)
        {
            VSIWin32TryLongFilename(pwszFilename);
            nLastError = 0;
            hFile = CreateFileW(
                pwszFilename, dwDesiredAccess,
                bShared ? FILE_SHARE_READ | FILE_SHARE_WRITE : 0, nullptr,
                dwCreationDisposition, dwFlagsAndAttributes, nullptr);
        }
        CPLFree(pwszFilename);
    }
    else
    {
        hFile = CreateFile(pszFilename, dwDesiredAccess,
                           bShared ? FILE_SHARE_READ | FILE_SHARE_WRITE : 0,
                           nullptr, dwCreationDisposition, dwFlagsAndAttributes,
                           nullptr);
    }

    if (hFile == INVALID_HANDLE_VALUE)
    {
        nLastError = GetLastError();
        const int nError = ErrnoFromGetLastError(nLastError);
        if (bSetError && nError != 0)
        {
            VSIError(VSIE_FileError, "%s: %s", pszFilename,
                     (nLastError == ERROR_SHARING_VIOLATION)
                         ? "file used by other process"
                         : strerror(nError));
        }
        errno = nError;
        return nullptr;
    }

    /* -------------------------------------------------------------------- */
    /*      Create a VSI file handle.                                       */
    /* -------------------------------------------------------------------- */
    VSIWin32Handle *poHandle = new VSIWin32Handle;

    poHandle->hFile = hFile;

    if (strchr(pszAccess, 'a') != nullptr)
        poHandle->Seek(0, SEEK_END);

    /* -------------------------------------------------------------------- */
    /*      If VSI_CACHE is set we want to use a cached reader instead      */
    /*      of more direct io on the underlying file.                       */
    /* -------------------------------------------------------------------- */
    if ((EQUAL(pszAccess, "r") || EQUAL(pszAccess, "rb")) &&
        CPLTestBool(CPLGetConfigOption("VSI_CACHE", "FALSE")))
    {
        return VSICreateCachedFile(poHandle);
    }
    else
    {
        return poHandle;
    }
}

/************************************************************************/
/*                                Stat()                                */
/************************************************************************/

int VSIWin32FilesystemHandler::Stat(const char *pszFilename,
                                    VSIStatBufL *pStatBuf, int nFlags)

{
    (void)nFlags;

#if defined(_MSC_VER) || __MSVCRT_VERSION__ >= 0x0601
    if (CPLTestBool(CPLGetConfigOption("GDAL_FILENAME_IS_UTF8", "YES")))
    {
        wchar_t *pwszFilename =
            CPLRecodeToWChar(pszFilename, CPL_ENC_UTF8, CPL_ENC_UCS2);

        bool bTryOtherStatImpl = false;
        int nResult = 0;
        if (VSIWin32IsLongFilename(pwszFilename))
        {
            bTryOtherStatImpl = true;
            nResult = -1;
        }
        else
        {
            nResult = _wstat64(pwszFilename, pStatBuf);
            if (nResult < 0)
            {
                DWORD nLastError = GetLastError();
                if (nLastError == ERROR_PATH_NOT_FOUND ||
                    nLastError == ERROR_FILENAME_EXCED_RANGE)
                {
                    VSIWin32TryLongFilename(pwszFilename);
                    bTryOtherStatImpl = true;
                }
            }
        }

        if (bTryOtherStatImpl)
        {
            // _wstat64 doesn't like \\?\ paths, so do our poor-man
            // stat like.
            // nResult = _wstat64( pwszFilename, pStatBuf );

            VSIVirtualHandle *poHandle = Open(pszFilename, "rb");
            if (poHandle != nullptr)
            {
                nResult = 0;
                memset(pStatBuf, 0, sizeof(VSIStatBufL));
                CPL_IGNORE_RET_VAL(poHandle->Seek(0, SEEK_END));
                pStatBuf->st_mode = S_IFREG;
                pStatBuf->st_size = poHandle->Tell();
                poHandle->Close();
                delete poHandle;
            }
            else
                nResult = -1;
        }

        CPLFree(pwszFilename);

        return nResult;
    }
    else
#endif
    {
        return (VSI_STAT64(pszFilename, pStatBuf));
    }
}

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

/*                               Unlink()                               */
/************************************************************************/

int VSIWin32FilesystemHandler::Unlink(const char *pszFilename)

{
#if defined(_MSC_VER) || __MSVCRT_VERSION__ >= 0x0601
    if (CPLTestBool(CPLGetConfigOption("GDAL_FILENAME_IS_UTF8", "YES")))
    {
        wchar_t *pwszFilename =
            CPLRecodeToWChar(pszFilename, CPL_ENC_UTF8, CPL_ENC_UCS2);

        const int nResult = _wunlink(pwszFilename);
        CPLFree(pwszFilename);
        return nResult;
    }
    else
#endif
    {
        return unlink(pszFilename);
    }
}

/************************************************************************/
/*                               Rename()                               */
/************************************************************************/

int VSIWin32FilesystemHandler::Rename(const char *oldpath, const char *newpath)

{
#if defined(_MSC_VER) || __MSVCRT_VERSION__ >= 0x0601
    if (CPLTestBool(CPLGetConfigOption("GDAL_FILENAME_IS_UTF8", "YES")))
    {
        wchar_t *pwszOldPath =
            CPLRecodeToWChar(oldpath, CPL_ENC_UTF8, CPL_ENC_UCS2);
        wchar_t *pwszNewPath =
            CPLRecodeToWChar(newpath, CPL_ENC_UTF8, CPL_ENC_UCS2);

        const int nResult = _wrename(pwszOldPath, pwszNewPath);
        CPLFree(pwszOldPath);
        CPLFree(pwszNewPath);
        return nResult;
    }
    else
#endif
    {
        return rename(oldpath, newpath);
    }
}

/************************************************************************/
/*                               Mkdir()                                */
/************************************************************************/

int VSIWin32FilesystemHandler::Mkdir(const char *pszPathname, long nMode)

{
    (void)nMode;
#if defined(_MSC_VER) || __MSVCRT_VERSION__ >= 0x0601
    if (CPLTestBool(CPLGetConfigOption("GDAL_FILENAME_IS_UTF8", "YES")))
    {
        wchar_t *pwszFilename =
            CPLRecodeToWChar(pszPathname, CPL_ENC_UTF8, CPL_ENC_UCS2);

        const int nResult = _wmkdir(pwszFilename);
        CPLFree(pwszFilename);
        return nResult;
    }
    else
#endif
    {
        return mkdir(pszPathname);
    }
}

/************************************************************************/
/*                               Rmdir()                                */
/************************************************************************/

int VSIWin32FilesystemHandler::Rmdir(const char *pszPathname)

{
#if defined(_MSC_VER) || __MSVCRT_VERSION__ >= 0x0601
    if (CPLTestBool(CPLGetConfigOption("GDAL_FILENAME_IS_UTF8", "YES")))
    {
        wchar_t *pwszFilename =
            CPLRecodeToWChar(pszPathname, CPL_ENC_UTF8, CPL_ENC_UCS2);

        const int nResult = _wrmdir(pwszFilename);
        CPLFree(pwszFilename);
        return nResult;
    }
    else
#endif
    {
        return rmdir(pszPathname);
    }
}

/************************************************************************/
/*                              ReadDir()                               */
/************************************************************************/

char **VSIWin32FilesystemHandler::ReadDirEx(const char *pszPath, int nMaxFiles)

{
#if defined(_MSC_VER) || __MSVCRT_VERSION__ >= 0x0601
    if (CPLTestBool(CPLGetConfigOption("GDAL_FILENAME_IS_UTF8", "YES")))
    {
        struct _wfinddata_t c_file;
        intptr_t hFile;
        char *pszFileSpec;
        CPLStringList oDir;

        if (strlen(pszPath) == 0)
            pszPath = ".";

        pszFileSpec = CPLStrdup(CPLSPrintf("%s\\*.*", pszPath));
        wchar_t *pwszFileSpec =
            CPLRecodeToWChar(pszFileSpec, CPL_ENC_UTF8, CPL_ENC_UCS2);

        if ((hFile = _wfindfirst(pwszFileSpec, &c_file)) != -1L)
        {
            do
            {
                oDir.AddStringDirectly(CPLRecodeFromWChar(
                    c_file.name, CPL_ENC_UCS2, CPL_ENC_UTF8));
                if (nMaxFiles > 0 && oDir.Count() > nMaxFiles)
                    break;
            } while (_wfindnext(hFile, &c_file) == 0);

            _findclose(hFile);
        }
        else
        {
            /* Should we generate an error???
             * For now we'll just return NULL (at the end of the function)
             */
        }

        CPLFree(pszFileSpec);
        CPLFree(pwszFileSpec);

        return oDir.StealList();
    }
    else
#endif
    {
        struct _finddata_t c_file;
        intptr_t hFile;
        char *pszFileSpec;
        CPLStringList oDir;

        if (strlen(pszPath) == 0)
            pszPath = ".";

        pszFileSpec = CPLStrdup(CPLSPrintf("%s\\*.*", pszPath));

        if ((hFile = _findfirst(pszFileSpec, &c_file)) != -1L)
        {
            do
            {
                oDir.AddString(c_file.name);
                if (nMaxFiles > 0 && oDir.Count() > nMaxFiles)
                    break;
            } while (_findnext(hFile, &c_file) == 0);

            _findclose(hFile);
        }
        else
        {
            /* Should we generate an error???
             * For now we'll just return NULL (at the end of the function)
             */
        }

        CPLFree(pszFileSpec);

        return oDir.StealList();
    }
}

/************************************************************************/
/*                        GetDiskFreeSpace()                            */
/************************************************************************/

GIntBig VSIWin32FilesystemHandler::GetDiskFreeSpace(const char *pszDirname)
{
    GIntBig nRet = -1;
    ULARGE_INTEGER nFreeBytesAvailable;
    if (GetDiskFreeSpaceEx(pszDirname, &nFreeBytesAvailable, nullptr, nullptr))
    {
        nRet = static_cast<GIntBig>(nFreeBytesAvailable.QuadPart);
    }
    return nRet;
}

/************************************************************************/
/*                      SupportsSparseFiles()                           */
/************************************************************************/

int VSIWin32FilesystemHandler::SupportsSparseFiles(const char *pszPath)
{
    CPLString osPath(pszPath);
    DWORD dwVolFlags = 0;
    if (CPLIsFilenameRelative(pszPath))
    {
        char *pszTmp = CPLGetCurrentDir();
        osPath = pszTmp;
        CPLFree(pszTmp);
    }
    if (osPath.size() >= 3 && osPath[1] == ':' &&
        (osPath[2] == '/' || osPath[2] == '\\'))
    {
        osPath.resize(3);
    }

    GetVolumeInformation(osPath.c_str(), nullptr, 0, nullptr, nullptr,
                         &dwVolFlags, nullptr, 0);
    return (dwVolFlags & FILE_SUPPORTS_SPARSE_FILES);
}

/************************************************************************/
/*                          IsLocal()                                   */
/************************************************************************/

bool VSIWin32FilesystemHandler::IsLocal(const char *pszPath)
{
    if (STARTS_WITH(pszPath, "\\\\") || STARTS_WITH(pszPath, "//"))
        return false;
    std::string osPath(pszPath);
    if (osPath.size() >= 3 && osPath[1] == ':' &&
        (osPath[2] == '\\' || osPath[2] == '/'))
    {
        osPath.resize(3);
        return GetDriveType(osPath.c_str()) != DRIVE_REMOTE;
    }
    return true;
}

/************************************************************************/
/*                     VSIInstallLargeFileHandler()                     */
/************************************************************************/

void VSIInstallLargeFileHandler()

{
    VSIFileManager::InstallHandler("", new VSIWin32FilesystemHandler);
}

#endif /* def WIN32 */