size_t doRead(char * buffer, size_t count)
{
ssize_t r = -1;
while ( (r=fd->read(buffer,count)) < 0 )
{
int const error = errno;
switch ( error )
{
case EINTR:
case EAGAIN:
// try again
break;
default:
{
libmaus2::exception::LibMausException se;
se.getStream() << "PosixInputOutputStreamBuffer::doRead(): read() failed: " << strerror(error) << std::endl;
se.finish();
throw se;
}
}
}
return r;
}
int_type underflow()
{
// if there is still data, then return it
if ( gptr() < egptr() )
return static_cast<int_type>(*uptr());
assert ( gptr() == egptr() );
// number of bytes for putback buffer
uint64_t const putbackcopy = std::min(
static_cast<uint64_t>(gptr() - eback()),
putbackspace
);
// copy bytes
std::copy(
gptr()-putbackcopy,
gptr(),
buffer.begin() + putbackspace - putbackcopy
);
// load data
uint64_t const uncompressedsize = fd->read(
buffer.begin()+putbackspace,
buffer.size()-putbackspace
);
// set buffer pointers
setgchecked(
buffer.begin()+putbackspace-putbackcopy,
buffer.begin()+putbackspace,
buffer.begin()+putbackspace+uncompressedsize);
symsread += uncompressedsize;
if ( uncompressedsize )
return static_cast<int_type>(*uptr());
else
return traits_type::eof();
}
