Re: [ros-dev] [ros-diffs] [hbelusca] 74619: [USETUP]: filesup module: - Add a NtPathToDiskPartComponents helper, that takes in input a fully qualified NT path to a file on hard disk, e.g.: \Device\Harddisk1\Partition2\foo\b...

[Thomas Faber]

On 2017-05-22 01:45, hbelusca(a)svn.reactos.org wrote:
>   +BOOLEAN
>  +NtPathToDiskPartComponents(
>  +    IN PCWSTR NtPath,
>  +    OUT PULONG pDiskNumber,
>  +    OUT PULONG pPartNumber,
>  +    OUT PCWSTR* PathComponent OPTIONAL)
>  +{
>  +    ULONG DiskNumber, PartNumber;
>  +    PCWSTR Path;
>  +
>  +    *pDiskNumber = 0;
>  +    *pPartNumber = 0;
>  +    if (PathComponent) *PathComponent = NULL;
>  +
>  +    Path = NtPath;
>  +
>  +    if (_wcsnicmp(Path, L"\\Device\\Harddisk", 16) != 0)
>  +    {
>  +        /* The NT path doesn't start with the prefix string, thus it cannot be a
> hard disk device path */
>  +        DPRINT1("'%S' : Not a possible hard disk device.\n", NtPath);
>  +        return FALSE;
>  +    }
>  +
>  +    Path += 16; 
Avoiding these magic numbers would be nice.
Options include:
* static string à la
  static const WCHAR DeviceHarddiskPath[] = L"\\Device\\Harddisk";
  _wcsnicmp(Path, DeviceHarddiskPath, ARRAYSIZE(DeviceHarddiskPath) - 1)
* simply using wcslen(L"\\Device\\Harddisk") (which should get optimized)
* making a "starts with" function
* using RtlPrefixUnicodeString



>   @@ -593,6 +705,31 @@
>        {
>            DPRINT1("Failed to open file %wZ, Status 0x%08lx\n", &Name,
> Status);
>            return Status;
>  +    }
>  +
>  +    if (FileSize)
>  +    {
>  +        /* Query the file size */
>  +        FILE_STANDARD_INFORMATION FileInfo;
>  +        Status = NtQueryInformationFile(*FileHandle,
>  +                                        &IoStatusBlock,
>  +                                        &FileInfo,
>  +                                        sizeof(FileInfo),
>  +                                        FileStandardInformation);
>  +        if (!NT_SUCCESS(Status))
>  +        {
>  +            DPRINT("NtQueryInformationFile() failed (Status %lx)\n", Status);
>  +            NtClose(*FileHandle);
>  +            *FileHandle = NULL;
>  +            return Status;
>  +        }
>  +
>  +        if (FileInfo.EndOfFile.HighPart != 0)
>  +            DPRINT1("WARNING!! The file %wZ is too large!\n", Name); 
Did you mean &Name?

[Hermès BÉLUSCA-MAÏTO]

Hi,

>  > +    if (_wcsnicmp(Path,
> L"\\Device\\Harddisk", 16) != 0)
> > +    {
> > +        /* The NT path doesn't start with the prefix string, thus it cannot be a
> hard disk device path */
> > +        DPRINT1("'%S' : Not a possible hard disk device.\n",
> NtPath);
> > +        return FALSE;
> > +    }
> > +
> > +    Path += 16; 
>   Avoiding these magic numbers would be nice.
>  Options include:
>  * static string à la
>    static const WCHAR DeviceHarddiskPath[] = L"\\Device\\Harddisk";
>    _wcsnicmp(Path, DeviceHarddiskPath, ARRAYSIZE(DeviceHarddiskPath) - 1)
>  * simply using wcslen(L"\\Device\\Harddisk") (which should get optimized)
>  * making a "starts with" function
>  * using RtlPrefixUnicodeString 
Yes, I may choose the RtlPrefix one but these options are better.


>  > +
> > +        if (FileInfo.EndOfFile.HighPart != 0)
> > +            DPRINT1("WARNING!! The file %wZ is too large!\n", Name);
>  Did you mean &Name? 
Correct