/// <summary>Create the ShortCircuitShm.</summary>
/// <param name="shmId">The ID to use.</param>
/// <param name="stream">
/// The stream that we're going to use to create this
/// shared memory segment.
/// Although this is a FileInputStream, we are going to
/// assume that the underlying file descriptor is writable
/// as well as readable. It would be more appropriate to use
/// a RandomAccessFile here, but that class does not have
/// any public accessor which returns a FileDescriptor,
/// unlike FileInputStream.
/// </param>
/// <exception cref="System.IO.IOException"/>
public ShortCircuitShm(ShortCircuitShm.ShmId shmId, FileInputStream stream)
{
if (!NativeIO.IsAvailable())
{
throw new NotSupportedException("NativeIO is not available.");
}
if (Shell.Windows)
{
throw new NotSupportedException("DfsClientShm is not yet implemented for Windows."
);
}
if (@unsafe == null)
{
throw new NotSupportedException("can't use DfsClientShm because we failed to " +
"load misc.Unsafe.");
}
this.shmId = shmId;
this.mmappedLength = GetUsableLength(stream);
this.baseAddress = NativeIO.POSIX.Mmap(stream.GetFD(), NativeIO.POSIX.MmapProtRead
| NativeIO.POSIX.MmapProtWrite, true, mmappedLength);
this.slots = new ShortCircuitShm.Slot[mmappedLength / BytesPerSlot];
this.allocatedSlots = new BitSet(slots.Length);
if (Log.IsTraceEnabled())
{
Log.Trace("creating " + this.GetType().Name + "(shmId=" + shmId + ", mmappedLength="
+ mmappedLength + ", baseAddress=" + string.Format("%x", baseAddress) + ", slots.length="
+ slots.Length + ")");
}
}
/// <exception cref="System.Exception"/>
public virtual void TestPosixFadvise()
{
if (Path.Windows)
{
return;
}
FileInputStream fis = new FileInputStream("/dev/zero");
try
{
NativeIO.POSIX.Posix_fadvise(fis.GetFD(), 0, 0, NativeIO.POSIX.PosixFadvSequential
);
}
catch (NotSupportedException)
{
// we should just skip the unit test on machines where we don't
// have fadvise support
Assume.AssumeTrue(false);
}
catch (NativeIOException)
{
}
finally
{
// ignore this error as FreeBSD returns EBADF even if length is zero
fis.Close();
}
try
{
NativeIO.POSIX.Posix_fadvise(fis.GetFD(), 0, 1024, NativeIO.POSIX.PosixFadvSequential
);
NUnit.Framework.Assert.Fail("Did not throw on bad file");
}
catch (NativeIOException nioe)
{
Assert.Equal(Errno.Ebadf, nioe.GetErrno());
}
try
{
NativeIO.POSIX.Posix_fadvise(null, 0, 1024, NativeIO.POSIX.PosixFadvSequential);
NUnit.Framework.Assert.Fail("Did not throw on null file");
}
catch (ArgumentNullException)
{
}
}
/// <exception cref="System.Exception"/>
public virtual void TestReadAndWrite()
{
FilePath path = new FilePath(TestBase, "testReadAndWrite");
path.Mkdirs();
SharedFileDescriptorFactory factory = SharedFileDescriptorFactory.Create("woot_",
new string[] { path.GetAbsolutePath() });
FileInputStream inStream = factory.CreateDescriptor("testReadAndWrite", 4096);
FileOutputStream outStream = new FileOutputStream(inStream.GetFD());
outStream.Write(101);
inStream.GetChannel().Position(0);
Assert.Equal(101, inStream.Read());
inStream.Close();
outStream.Close();
FileUtil.FullyDelete(path);
}
protected internal static FileInputStream ForceSecureOpenForRead(FilePath f, string
expectedOwner, string expectedGroup)
{
FileInputStream fis = new FileInputStream(f);
bool success = false;
try
{
NativeIO.POSIX.Stat stat = NativeIO.POSIX.GetFstat(fis.GetFD());
CheckStat(f, stat.GetOwner(), stat.GetGroup(), expectedOwner, expectedGroup);
success = true;
return(fis);
}
finally
{
if (!success)
{
fis.Close();
}
}
}
