private void UnlockFile(long offset, long count)
{
#if !SILICONSTUDIO_PLATFORM_WINDOWS_RUNTIME && !SILICONSTUDIO_PLATFORM_MONO_MOBILE
var fileStream = stream as FileStream;
if (fileStream == null)
{
return;
}
#if SILICONSTUDIO_PLATFORM_WINDOWS_DESKTOP
var countLow = (uint)count;
var countHigh = (uint)(count >> 32);
var overlapped = new NativeLockFile.OVERLAPPED()
{
internalLow = 0,
internalHigh = 0,
offsetLow = (uint)offset,
offsetHigh = (uint)(offset >> 32),
hEvent = IntPtr.Zero,
};
if (!NativeLockFile.UnlockFileEx(fileStream.SafeFileHandle, 0, countLow, countHigh, ref overlapped))
{
throw new IOException("Couldn't unlock file.");
}
#else
fileStream.Unlock(offset, count);
#endif
#endif
}
private void LockFile(long offset, long count, bool exclusive)
{
#if !SILICONSTUDIO_PLATFORM_WINDOWS_RUNTIME
var fileStream = stream as FileStream;
if (fileStream == null)
{
return;
}
#if SILICONSTUDIO_PLATFORM_ANDROID
// Android does not support large file and thus is limited to files
// whose sizes are less than 2GB.
// We substract the offset to not go beyond the 2GB limit.
count = (count + offset > int.MaxValue) ? int.MaxValue - offset: count;
#endif
#if SILICONSTUDIO_PLATFORM_WINDOWS_DESKTOP
var countLow = (uint)count;
var countHigh = (uint)(count >> 32);
var overlapped = new NativeLockFile.OVERLAPPED()
{
internalLow = 0,
internalHigh = 0,
offsetLow = (uint)offset,
offsetHigh = (uint)(offset >> 32),
hEvent = IntPtr.Zero,
};
if (!NativeLockFile.LockFileEx(fileStream.SafeFileHandle, exclusive ? NativeLockFile.LOCKFILE_EXCLUSIVE_LOCK : 0, 0, countLow, countHigh, ref overlapped))
{
throw new IOException("Couldn't lock file.");
}
#elif SILICONSTUDIO_RUNTIME_CORECLR
// There is no implementation of FileStream.Lock on CoreCLR
#else
bool tryAgain;
do
{
tryAgain = false;
try
{
fileStream.Lock(offset, count);
}
catch (IOException)
{
tryAgain = true;
}
} while (tryAgain);
#endif
#endif
}
private void LockFile(long offset, long count, bool exclusive)
{
#if !SILICONSTUDIO_PLATFORM_WINDOWS_RUNTIME && !SILICONSTUDIO_PLATFORM_MONO_MOBILE
var fileStream = stream as FileStream;
if (fileStream == null)
{
return;
}
#if SILICONSTUDIO_PLATFORM_WINDOWS_DESKTOP
var countLow = (uint)count;
var countHigh = (uint)(count >> 32);
var overlapped = new NativeLockFile.OVERLAPPED()
{
internalLow = 0,
internalHigh = 0,
offsetLow = (uint)offset,
offsetHigh = (uint)(offset >> 32),
hEvent = IntPtr.Zero,
};
if (!NativeLockFile.LockFileEx(fileStream.SafeFileHandle, exclusive ? NativeLockFile.LOCKFILE_EXCLUSIVE_LOCK : 0, 0, countLow, countHigh, ref overlapped))
{
throw new IOException("Couldn't lock file.");
}
#elif SILICONSTUDIO_RUNTIME_CORECLR
// There is no implementation of FileStream.Lock on CoreCLR
#else
bool tryAgain;
do
{
tryAgain = false;
try
{
fileStream.Lock(offset, count);
}
catch (IOException)
{
tryAgain = true;
}
} while (tryAgain);
#endif
#endif
}
/// <summary>
/// Releases the file lock.
/// </summary>
public void Dispose()
{
if (lockFile != null)
{
var overlapped = new NativeLockFile.OVERLAPPED();
NativeLockFile.UnlockFileEx(lockFile.SafeFileHandle, 0, uint.MaxValue, uint.MaxValue, ref overlapped);
lockFile.Dispose();
// Try to delete the file
// Ideally we would use FileOptions.DeleteOnClose, but it doesn't seem to work well with FileShare for second instance
try
{
File.Delete(lockFile.Name);
}
catch (Exception)
{
}
lockFile = null;
}
}
private void UnlockFile(long offset, long count)
{
#if !SILICONSTUDIO_PLATFORM_WINDOWS_RUNTIME
var fileStream = stream as FileStream;
if (fileStream == null)
{
return;
}
#if SILICONSTUDIO_PLATFORM_ANDROID
// See comment on `LockFile`.
count = (count + offset > int.MaxValue) ? int.MaxValue - offset: count;
#endif
#if SILICONSTUDIO_PLATFORM_WINDOWS_DESKTOP
var countLow = (uint)count;
var countHigh = (uint)(count >> 32);
var overlapped = new NativeLockFile.OVERLAPPED()
{
internalLow = 0,
internalHigh = 0,
offsetLow = (uint)offset,
offsetHigh = (uint)(offset >> 32),
hEvent = IntPtr.Zero,
};
if (!NativeLockFile.UnlockFileEx(fileStream.SafeFileHandle, 0, countLow, countHigh, ref overlapped))
{
throw new IOException("Couldn't unlock file.");
}
#elif SILICONSTUDIO_RUNTIME_CORECLR
// There is no implementation of FileStream.Unlock on CoreCLR
#else
fileStream.Unlock(offset, count);
#endif
#endif
}
/// <summary>
/// Tries to take ownership of the file lock within a given delay.
/// </summary>
/// <param name="name">A unique name identifying the file lock.</param>
/// <param name="millisecondsTimeout">The maximum delay to wait before returning, in milliseconds.</param>
/// <returns>A new instance of <see cref="FileLock"/> if the ownership could be taken, <c>null</c> otherwise.</returns>
/// <remarks>
/// The returned <see cref="FileLock"/> must be disposed to release the file lock.
/// Calling this method with 0 for <see paramref="millisecondsTimeout"/> is equivalent to call <see cref="TryLock"/>.
/// Calling this method with a negative value for <see paramref="millisecondsTimeout"/> is equivalent to call <see cref="Wait(string)"/>.
/// </remarks>
public static FileLock Wait(string name, int millisecondsTimeout)
{
var fileLock = BuildFileLock(name);
try
{
if (millisecondsTimeout != 0 && millisecondsTimeout != -1)
throw new NotImplementedException("GlobalMutex.Wait() is implemented only for millisecondsTimeout 0 or -1");
var overlapped = new NativeLockFile.OVERLAPPED();
bool hasHandle = NativeLockFile.LockFileEx(fileLock.SafeFileHandle, NativeLockFile.LOCKFILE_EXCLUSIVE_LOCK | (millisecondsTimeout == 0 ? NativeLockFile.LOCKFILE_FAIL_IMMEDIATELY : 0), 0, uint.MaxValue, uint.MaxValue, ref overlapped);
return hasHandle == false ? null : new FileLock(fileLock);
}
catch (AbandonedMutexException)
{
return new FileLock(fileLock);
}
}