bool do_copy()
// Copy the data. Return true on success, false on failure.
{
if (m_done_copy)
{
assert(0);
log_error("gameswf::tools::copy_helper() already done copy\n");
return false;
}
m_done_copy = true;
int current_in_pos = m_in->get_position();
int bytes_to_copy = current_in_pos - m_initial_in_pos;
if (bytes_to_copy > 0)
{
m_in->set_position(m_initial_in_pos);
int bytes_copied = m_out->copy_bytes(m_in, bytes_to_copy);
if (bytes_copied != bytes_to_copy)
{
m_in->set_position(current_in_pos); // fixup
return false;
}
assert(m_in->get_position() == current_in_pos);
return true;
}
else
{
log_error("gameswf::tools::copy_helper asked to copy %d bytes\n",
bytes_to_copy);
return false;
}
}
copy_helper(tu_file* in, tu_file* out)
:
m_in(in),
m_out(out),
m_initial_in_pos(in->get_position()),
m_done_copy(false)
{
assert(m_in && m_in->get_error() == TU_FILE_NO_ERROR);
assert(m_out && m_out->get_error() == TU_FILE_NO_ERROR);
}
void rewind_unused_bytes()
// If we have unused bytes in our input buffer, rewind
// to before they started.
{
if (m_zstream.avail_in > 0)
{
int pos = m_in->get_position();
int rewound_pos = pos - m_zstream.avail_in;
assert(pos >= 0);
assert(pos >= m_initial_stream_pos);
assert(rewound_pos >= 0);
assert(rewound_pos >= m_initial_stream_pos);
m_in->set_position(rewound_pos);
}
}
int inflate_from_stream(void* dst, int bytes)
{
if (m_error)
{
return 0;
}
m_zstream.next_out = (unsigned char*) dst;
m_zstream.avail_out = bytes;
for (;;)
{
if (m_zstream.avail_in == 0)
{
// Get more raw data.
int new_bytes = m_in->read_bytes(m_rawdata, ZBUF_SIZE);
if (new_bytes == 0)
{
// The cupboard is bare! We have nothing to feed to inflate().
break;
}
else
{
m_zstream.next_in = m_rawdata;
m_zstream.avail_in = new_bytes;
}
}
int err = inflate(&m_zstream, Z_SYNC_FLUSH);
if (err == Z_STREAM_END)
{
m_at_eof = true;
break;
}
if (err != Z_OK)
{
// something's wrong.
m_error = 1;
break;
}
if (m_zstream.avail_out == 0)
{
break;
}
}
int bytes_read = bytes - m_zstream.avail_out;
m_logical_stream_pos += bytes_read;
return bytes_read;
}
void reset()
// Discard current results and rewind to the beginning.
// Necessary in order to seek backwards.
{
m_error = 0;
m_at_eof = 0;
int err = inflateReset(&m_zstream);
if (err != Z_OK) {
m_error = 1;
return;
}
m_zstream.next_in = 0;
m_zstream.avail_in = 0;
m_zstream.next_out = 0;
m_zstream.avail_out = 0;
// Rewind the underlying stream.
m_in->set_position(m_initial_stream_pos);
m_logical_stream_pos = 0;
}
