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Diffstat (limited to 'lib/common/ZeroStream.cpp')
| -rw-r--r-- | lib/common/ZeroStream.cpp | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/lib/common/ZeroStream.cpp b/lib/common/ZeroStream.cpp new file mode 100644 index 00000000..e9717a1d --- /dev/null +++ b/lib/common/ZeroStream.cpp @@ -0,0 +1,208 @@ +// distribution boxbackup-0.11rc1 (svn version: 2023_2024) +// +// Copyright (c) 2003 - 2006 +// Ben Summers and contributors. All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions +// are met: +// 1. Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// 2. Redistributions in binary form must reproduce the above copyright +// notice, this list of conditions and the following disclaimer in the +// documentation and/or other materials provided with the distribution. +// 3. All use of this software and associated advertising materials must +// display the following acknowledgment: +// This product includes software developed by Ben Summers. +// 4. The names of the Authors may not be used to endorse or promote +// products derived from this software without specific prior written +// permission. +// +// [Where legally impermissible the Authors do not disclaim liability for +// direct physical injury or death caused solely by defects in the software +// unless it is modified by a third party.] +// +// THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR +// IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +// DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, +// INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, +// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN +// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +// POSSIBILITY OF SUCH DAMAGE. +// +// +// +// -------------------------------------------------------------------------- +// +// File +// Name: ZeroStream.cpp +// Purpose: An IOStream which returns all zeroes up to a certain size +// Created: 2007/04/28 +// +// -------------------------------------------------------------------------- + +#include "Box.h" +#include "ZeroStream.h" +#include "CommonException.h" + +#include <string.h> + +#include "MemLeakFindOn.h" + +// -------------------------------------------------------------------------- +// +// Function +// Name: ZeroStream::ZeroStream(IOStream::pos_type) +// Purpose: Constructor +// Created: 2007/04/28 +// +// -------------------------------------------------------------------------- +ZeroStream::ZeroStream(IOStream::pos_type size) +: mSize(size), mPosition(0) +{ } + + +// -------------------------------------------------------------------------- +// +// Function +// Name: ZeroStream::Read(void *, int) +// Purpose: Reads bytes from the file +// Created: 2007/01/16 +// +// -------------------------------------------------------------------------- +int ZeroStream::Read(void *pBuffer, int NBytes, int Timeout) +{ + ASSERT(NBytes > 0); + + int bytesToRead = NBytes; + + if (bytesToRead > mSize - mPosition) + { + bytesToRead = mSize - mPosition; + } + + memset(pBuffer, 0, bytesToRead); + mPosition += bytesToRead; + + return bytesToRead; +} + + +// -------------------------------------------------------------------------- +// +// Function +// Name: ZeroStream::BytesLeftToRead() +// Purpose: Returns number of bytes to read (may not be most efficient function ever) +// Created: 2007/01/16 +// +// -------------------------------------------------------------------------- +IOStream::pos_type ZeroStream::BytesLeftToRead() +{ + return mSize - mPosition; +} + + +// -------------------------------------------------------------------------- +// +// Function +// Name: ZeroStream::Write(void *, int) +// Purpose: Writes bytes to the underlying stream (not supported) +// Created: 2003/07/31 +// +// -------------------------------------------------------------------------- +void ZeroStream::Write(const void *pBuffer, int NBytes) +{ + THROW_EXCEPTION(CommonException, NotSupported); +} + + +// -------------------------------------------------------------------------- +// +// Function +// Name: ZeroStream::GetPosition() +// Purpose: Get position in stream +// Created: 2003/08/21 +// +// -------------------------------------------------------------------------- +IOStream::pos_type ZeroStream::GetPosition() const +{ + return mPosition; +} + + +// -------------------------------------------------------------------------- +// +// Function +// Name: ZeroStream::Seek(pos_type, int) +// Purpose: Seeks within file, as lseek, invalidate buffer +// Created: 2003/07/31 +// +// -------------------------------------------------------------------------- +void ZeroStream::Seek(IOStream::pos_type Offset, int SeekType) +{ + switch (SeekType) + { + case SeekType_Absolute: + { + mPosition = Offset; + } + break; + + case SeekType_Relative: + { + mPosition += Offset; + } + break; + + case SeekType_End: + { + mPosition = mSize - Offset; + } + } +} + + +// -------------------------------------------------------------------------- +// +// Function +// Name: ZeroStream::Close() +// Purpose: Closes the underlying stream (not needed) +// Created: 2003/07/31 +// +// -------------------------------------------------------------------------- +void ZeroStream::Close() +{ + THROW_EXCEPTION(CommonException, NotSupported); +} + + +// -------------------------------------------------------------------------- +// +// Function +// Name: ZeroStream::StreamDataLeft() +// Purpose: Any data left to write? +// Created: 2003/08/02 +// +// -------------------------------------------------------------------------- +bool ZeroStream::StreamDataLeft() +{ + return false; +} + +// -------------------------------------------------------------------------- +// +// Function +// Name: ZeroStream::StreamClosed() +// Purpose: Is the stream closed? +// Created: 2003/08/02 +// +// -------------------------------------------------------------------------- +bool ZeroStream::StreamClosed() +{ + return false; +} + |