/// <summary>
/// The Seek method changes the seek pointer to a new location. The new location is relative to either the beginning of the streamIndex, the end of the streamIndex, or the current seek pointer.
/// </summary>
/// <param name="offset">The displacement to be added to the location indicated by the <paramref name="origin"/> parameter. If <paramref name="origin"/> is <see cref="System.IO.SeekOrigin.Begin"/>, this is interpreted as an unsigned value rather than a signed value.</param>
/// <param name="origin">The origin for the displacement specified in <paramref name="offset"/>. The origin can be the beginning of the file (<see cref="System.IO.SeekOrigin.Begin"/>), the current seek pointer (<see cref="System.IO.SeekOrigin.Current"/>), or the end of the file (<see cref="System.IO.SeekOrigin.End"/>). For more information about values, see the <see cref="System.IO.SeekOrigin"/> enumeration.</param>
/// <param name="newPosition">A pointer to the location where this method writes the value of the new seek pointer from the beginning of the streamIndex. You can set this pointer to <see cref="System.IntPtr.Zero"/>. In this case, this method does not provide the new seek pointer.</param>
/// <returns>An HRESULT.</returns>
public HResult Seek(long offset, System.IO.SeekOrigin origin, IntPtr newPosition)
{
if (m_stream == null)
{
return(HResult.STG_E_REVERTED);
}
if (!m_stream.CanSeek)
{
return(HResult.STG_E_INVALIDFUNCTION);
}
if ((origin != SeekOrigin.Begin) && (origin != SeekOrigin.Current) && (origin != SeekOrigin.End))
{
return(HResult.STG_E_INVALIDFUNCTION);
}
long newPos = m_stream.Seek(offset, (SeekOrigin)origin);
if (newPosition != IntPtr.Zero)
{
Marshal.WriteInt64(newPosition, newPos);
}
return(HResult.S_OK);
}
// position < 0, == 0, and > 0 cases accounted for
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
if (!CanSeek)
{
//If both can't seek, not supported.
throw new NotSupportedException();
}
long originLong = 0;
//Begin case is accounted for with default originLong = 0 value.
if (origin == System.IO.SeekOrigin.Current)
{
originLong = Position;
}
else if (origin == System.IO.SeekOrigin.End)
{
originLong = Length;
}
/*
* if offset is negative, it'll go to an element preceeded by SeekOrigin
* Also, if the sum stored in Position is negative, our Property's set
* will put it back to 0 as per Evan's specs.
*/
_position = offset + originLong;
return(Position);
}
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
CheckDisposed();
long effectiveOffset = offset;
if (origin == SeekOrigin.Current)
{
effectiveOffset += _position;
}
else if (origin == SeekOrigin.End)
{
effectiveOffset += Length;
}
if (effectiveOffset < 0)
{
throw new IOException("Attempt to move before beginning of disk");
}
else
{
Position = effectiveOffset;
return(Position);
}
}
public long Seek(long offset, System.IO.SeekOrigin origin)
{
Tracing.Log(Tracing.Debug, "Entered");
switch (origin)
{
case System.IO.SeekOrigin.Begin:
if (offset >= 0)
{
_pos = offset;
}
break;
case System.IO.SeekOrigin.Current:
if (_pos + offset >= 0)
{
_pos += offset;
}
break;
case System.IO.SeekOrigin.End:
long len = this.Length;
if (len + offset >= 0)
{
_pos = len + offset;
}
break;
default:
throw new NotSupportedException("Unidentified SeekOrigin argument");
}
Tracing.Log(Tracing.Debug, "Exit");
return((long)_pos);
}
/// <summary>
/// When overridden in a derived class, sets the position within the current stream.
/// </summary>
/// <param name="offset">A frame index offset relative to the origin parameter.</param>
/// <param name="origin">A value of type System.IO.SeekOrigin indicating the reference point used to obtain the new position.</param>
/// <returns>The new position within the current stream.</returns>
/// <exception cref="NotSupportedException">Seek operation is not supported by the current stream.</exception>
public virtual long Seek(long offset, System.IO.SeekOrigin origin = SeekOrigin.Current)
{
if (!this.CanSeek)
{
throw new NotSupportedException("Seek operation is not supported by the current stream.");
}
long newPosition = 0;
switch (origin)
{
case SeekOrigin.Begin:
newPosition = offset;
break;
case SeekOrigin.Current:
newPosition = this.Position + offset;
break;
case SeekOrigin.End:
newPosition = this.Length + offset;
break;
}
var currentFrame = System.Math.Min(this.Length - 1, System.Math.Max(0, newPosition));
return(currentFrame);
}
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
using (new Synchronizer(this))
{
Stream stream = this.GetStream();
return(stream.Seek(offset, origin));
}
}
/// <summary>
/// Sets the position within the current stream.
/// <para>Warning: the underlying OpenCV function seeks to nearest key-frame, therefore the seek operation may not be frame-accurate.</para>
/// </summary>
/// <param name="offset">A frame index offset relative to the origin parameter.</param>
/// <param name="origin">A value of type System.IO.SeekOrigin indicating the reference point used to obtain the new position.</param>
/// <returns>The new position within the current stream.</returns>
public override long Seek(long offset, System.IO.SeekOrigin origin = SeekOrigin.Current)
{
var frameIndex = base.Seek(offset, origin);
CvInvoke.cvSetCaptureProperty(capturePtr, CaptureProperty.PosFrames, frameIndex);
return(Position);
}
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
if (mStream == null)
{
throw new ObjectDisposedException("SambaInputStream");
}
throw new NotSupportedException();
}
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
var x = _innerStream.Seek(offset, origin);
// workitem 10178
Ionic.Zip.SharedUtilities.Workaround_Ladybug318918(_innerStream);
return(x);
}
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
if (_disposed)
{
throw new ObjectDisposedException(this.GetType().FullName);
}
throw new NotSupportedException();
}
public virtual long Seek(long lOff, System.IO.SeekOrigin nFrom)
{
if (!stream_.CanSeek)
{
throw new ApplicationException("Stream didn't support seek");
}
return(stream_.Seek(lOff, nFrom));
}
/// <inheritdoc/>
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
_debugWriter?.Write("StreamWrapper.Seek, offset={0}, origin={1}", offset, origin);
var result = _istream.Seek(offset, origin);
_debugWriter?.WriteLine("... result: {0}", result);
_debugWriter?.Flush();
return(result);
}
public void Seek(int Offset, System.IO.SeekOrigin Origin)
{
g_eofFlag = false;
g_offset = (int)g_file.BaseStream.Seek(Offset, Origin);
g_file.DiscardBufferedData();
LoadBuffer();
}
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
if (origin.Equals(System.IO.SeekOrigin.Current))
{
return(this.input.skip(offset));
}
else
{
throw new java.lang.IllegalArgumentException(new java.lang.UnsupportedOperationException("Only seek from current position yet implemented"));
}
}
public override long Seek (long offset, System.IO.SeekOrigin origin)
{
int bufRest = bufLength - bufPos;
if (origin == SeekOrigin.Current)
if (offset < bufRest)
return buffer [bufPos + offset];
else
return stream.Seek (offset - bufRest, origin);
else
return stream.Seek (offset, origin);
}
public override long Seek(long offset, System.IO.SeekOrigin loc)
{
switch (loc)
{
case SeekOrigin.Begin: _byteBuffer.writerIndex = (int)offset; return(_byteBuffer.writerIndex);
case SeekOrigin.Current: _byteBuffer.writerIndex += (int)offset; return(_byteBuffer.writerIndex);
default: _byteBuffer.writerIndex -= (int)offset; return(_byteBuffer.writerIndex);
}
}
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
if (origin.Equals(SeekOrigin.End))
{
Position = _length;
}
else
{
Position = offset;
}
return(Position);
}
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
// EPIC GAMES START
if (origin == SeekOrigin.Begin || origin == SeekOrigin.End)
{
return(_innerStream.Seek(_originalPosition + offset, origin) - _originalPosition);
}
else
{
return(_innerStream.Seek(offset, origin) - _originalPosition);
}
// EPIC GAMES END
}
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
switch (origin)
{
case SeekOrigin.Begin: return(position = (uint)offset);
case SeekOrigin.Current: return(position += (uint)offset);
case SeekOrigin.End: return(position = (uint)Length - (uint)offset);
default: throw new Exception("Invalid SeekOrigin.");
}
}
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
lock (this) {
if (m_isPeeking)
{
throw new NotSupportedException("seeking not supported, while peeking");
}
else
{
long result = m_stream.Seek(offset, origin);
m_peekBuffer.Close();
m_peekBuffer = null; // peek-buffer useless after seek
return(result);
}
}
}
/// <summary>Seeks to the specified offset. Origin is always Current, Begin and End are ignored.</summary>
/// <param name="offset">Offset to seek to</param>
/// <param name="origin">Origin. Always System.IO.SeekOrigin.Current</param>
/// <returns>New position, meaningless in a circularbuffer</returns>
public override long Seek(long offset, IO.SeekOrigin origin)
{
if (this.buffer.writePosition + offset >= this.buffer.internalData.Length)
{
this.buffer.writePosition = this.buffer.writePosition + offset - this.buffer.internalData.Length;
}
else if (this.buffer.writePosition + offset < 0)
{
this.buffer.writePosition = this.buffer.internalData.Length + this.buffer.writePosition + offset;
}
else
{
this.buffer.writePosition += offset;
}
return(this.buffer.writePosition);
}
public void Seek(long offset, System.IO.SeekOrigin origin)
{
if (streamReader == null)
{
streamReader = new StreamReader(stream, contentEncoding);
}
if (streamWriter == null)
{
streamWriter = new StreamWriter(stream, contentEncoding);
}
streamWriter.Flush();
stream.Seek(offset, origin);
streamWriter.Flush();
this.streamReader.DiscardBufferedData();
}
/// <summary>
/// Seek the stream to given position within the file relative to given origin.
/// </summary>
/// <param name="offset"></param>
/// <param name="origin"></param>
/// <returns></returns>
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
switch (origin)
{
case System.IO.SeekOrigin.Begin:
Position = offset;
break;
case System.IO.SeekOrigin.Current:
Position = Position + offset;
break;
case System.IO.SeekOrigin.End:
Position = Length + offset;
break;
}
return(Position);
}
/// <summary>
/// Moves the current position value in a file
/// </summary>
/// <param name="hf">The file handle.</param>
/// <param name="dist">Number of bytes to move the pointer.</param>
/// <param name="seektype">A value that specifies how the pointer should be moved. Valid values are SEEK_CUR, SEEK_END, and SEEK_SET.</param>
/// <param name="err">Error return.</param>
/// <param name="userData">User data passed to the function from CAB API.</param>
/// <returns>Returns the new file position. Returns -1 on error.</returns>
public static int FileSeek(
IntPtr hf,
int dist,
int seektype,
ref int err,
object userData)
{
try
{
FileStream f = FileStreamFromHandle(hf);
System.IO.SeekOrigin origin = FCntl.SeekOriginFromSeekType(seektype);
// cast to int because FileStream.Seek returns a long
return((int)f.Seek(dist, origin));
}
catch (Exception)
{
return(-1);
}
}
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
int bufRest = bufLength - bufPos;
if (origin == SeekOrigin.Current)
{
if (offset < bufRest)
{
return(buffer [bufPos + offset]);
}
else
{
return(stream.Seek(offset - bufRest, origin));
}
}
else
{
return(stream.Seek(offset, origin));
}
}
/// <summary>
/// Sets the position within the current stream.
/// </summary>
/// <param name="offset">A byte offset relative to the origin parameter.</param>
/// <param name="origin">A value of type SeekOrigin indicating the reference point used to obtain the new position.</param>
/// <returns>The new position within the current stream.</returns>
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
if (_imageStream != null)
{
long position = 0;
var pos = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(long)));
Marshal.WriteInt64(pos, 0);
// The enum values of SeekOrigin match the enum values of
// STREAM_SEEK, so we can just cast the origin to an integer.
_imageStream.Seek(offset, (int)origin, pos);
position = Marshal.ReadInt64(pos);
Marshal.FreeHGlobal(pos);
return(position);
}
else
{
return(_stream.Seek(offset, origin));
}
}
/// <summary>
/// Sets the position within the current stream.
/// </summary>
/// <param name="offset">A byte offset relative to the origin parameter.</param>
/// <param name="origin">A value of type <see cref="SeekOrigin"/> indicating the
/// reference point used to obtain the new position.</param>
/// <returns>The new position within the current stream.</returns>
public override long Seek(long offset, SeekOrigin origin)
{
SDK.SeekOrigin sdkOrigin;
switch (origin)
{
case SeekOrigin.Begin:
sdkOrigin = SDK.SeekOrigin.Begin;
break;
case SeekOrigin.Current:
sdkOrigin = SDK.SeekOrigin.Current;
break;
case SeekOrigin.End:
sdkOrigin = SDK.SeekOrigin.End;
break;
default:
throw new ArgumentException("Not a valid enum value", nameof(origin));
}
if (CanonSDK.IsVerGE34)
ErrorHandler.CheckError(CanonSDK.EdsSeek(_Reference, offset, sdkOrigin)); }
public long Seek(long offset, System.IO.SeekOrigin loc)
{
if (lines != null)
{
switch (loc)
{
case SeekOrigin.Begin:
Position = offset;
break;
case SeekOrigin.Current:
Position += offset;
break;
case SeekOrigin.End:
Position = lines.Count + offset;
break;
}
Position = System.Math.Min(Position, lines.Count);
Position = System.Math.Max(Position, 0);
}
return(Position);
}
/// <summary>
/// Calling this method always throws a <see cref="NotSupportedException"/>.
/// </summary>
/// <param name="offset">
/// The offset to seek to....
/// IF THIS METHOD ACTUALLY DID ANYTHING.
/// </param>
/// <param name="origin">
/// The reference specifying how to apply the offset.... IF
/// THIS METHOD ACTUALLY DID ANYTHING.
/// </param>
///
/// <returns>nothing. This method always throws.</returns>
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
throw new NotSupportedException();
}
/// <summary>
/// Seek in the stream.
/// </summary>
/// <param name="offset">the offset point to seek to</param>
/// <param name="origin">the reference point from which to seek</param>
/// <returns>The new position</returns>
public override long Seek(long offset, System.IO.SeekOrigin origin)
{
return(_s.Seek(offset, origin));
}
