* Copyright 2014, Ingo Weinhold, ingo_weinhold@gmx.de.
* Distributed under the terms of the MIT License.
*/
#include <DataPositionIOWrapper.h>
#include <stdio.h>
BDataPositionIOWrapper::BDataPositionIOWrapper(BDataIO* io)
:
BPositionIO(),
fIO(io),
fPosition(0)
{
}
BDataPositionIOWrapper::~BDataPositionIOWrapper()
{
}
ssize_t
BDataPositionIOWrapper::Read(void* buffer, size_t size)
{
ssize_t bytesRead = fIO->Read(buffer, size);
if (bytesRead > 0)
fPosition += bytesRead;
return bytesRead;
}
ssize_t
BDataPositionIOWrapper::Write(const void* buffer, size_t size)
{
ssize_t bytesWritten = fIO->Write(buffer, size);
if (bytesWritten > 0)
fPosition += bytesWritten;
return bytesWritten;
}
ssize_t
BDataPositionIOWrapper::ReadAt(off_t position, void* buffer, size_t size)
{
if (position != fPosition)
return B_NOT_SUPPORTED;
return Read(buffer, size);
}
ssize_t
BDataPositionIOWrapper::WriteAt(off_t position, const void* buffer,
size_t size)
{
if (position != fPosition)
return B_NOT_SUPPORTED;
return Write(buffer, size);
}
off_t
BDataPositionIOWrapper::Seek(off_t position, uint32 seekMode)
{
switch (seekMode) {
case SEEK_CUR:
return position == 0 ? B_OK : B_NOT_SUPPORTED;
case SEEK_SET:
return position == fPosition ? B_OK : B_NOT_SUPPORTED;
case SEEK_END:
return B_NOT_SUPPORTED;
default:
return B_BAD_VALUE;
}
}
off_t
BDataPositionIOWrapper::Position() const
{
return fPosition;
}
status_t
BDataPositionIOWrapper::SetSize(off_t size)
{
return size == fPosition ? B_OK : B_NOT_SUPPORTED;
}
status_t
BDataPositionIOWrapper::GetSize(off_t* size) const
{
return B_NOT_SUPPORTED;
}
