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+/*
+ Copyright (c) 2007-2010 iMatix Corporation
+
+ This file is part of 0MQ.
+
+ 0MQ is free software; you can redistribute it and/or modify it under
+ the terms of the Lesser GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ 0MQ is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ Lesser GNU General Public License for more details.
+
+ You should have received a copy of the Lesser GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "decoder.hpp"
+#include "i_inout.hpp"
+#include "wire.hpp"
+#include "err.hpp"
+
+zmq::decoder_t::decoder_t (size_t bufsize_) :
+ decoder_base_t <decoder_t> (bufsize_),
+ destination (NULL)
+{
+ zmq_msg_init (&in_progress);
+
+ // At the beginning, read one byte and go to one_byte_size_ready state.
+ next_step (tmpbuf, 1, &decoder_t::one_byte_size_ready);
+}
+
+zmq::decoder_t::~decoder_t ()
+{
+ zmq_msg_close (&in_progress);
+}
+
+void zmq::decoder_t::set_inout (i_inout *destination_)
+{
+ destination = destination_;
+}
+
+bool zmq::decoder_t::one_byte_size_ready ()
+{
+ // First byte of size is read. If it is 0xff read 8-byte size.
+ // Otherwise allocate the buffer for message data and read the
+ // message data into it.
+ if (*tmpbuf == 0xff)
+ next_step (tmpbuf, 8, &decoder_t::eight_byte_size_ready);
+ else {
+
+ // There has to be at least one byte (the flags) in the message).
+ if (!*tmpbuf) {
+ decoding_error ();
+ return false;
+ }
+
+ // in_progress is initialised at this point so in theory we should
+ // close it before calling zmq_msg_init_size, however, it's a 0-byte
+ // message and thus we can treat it as uninitialised...
+ int rc = zmq_msg_init_size (&in_progress, *tmpbuf - 1);
+ if (rc != 0 && errno == ENOMEM) {
+ decoding_error ();
+ return false;
+ }
+ errno_assert (rc == 0);
+
+ next_step (tmpbuf, 1, &decoder_t::flags_ready);
+ }
+ return true;
+}
+
+bool zmq::decoder_t::eight_byte_size_ready ()
+{
+ // 8-byte size is read. Allocate the buffer for message body and
+ // read the message data into it.
+ size_t size = (size_t) get_uint64 (tmpbuf);
+
+ // There has to be at least one byte (the flags) in the message).
+ if (!size) {
+ decoding_error ();
+ return false;
+ }
+
+ // in_progress is initialised at this point so in theory we should
+ // close it before calling zmq_msg_init_size, however, it's a 0-byte
+ // message and thus we can treat it as uninitialised...
+ int rc = zmq_msg_init_size (&in_progress, size - 1);
+ if (rc != 0 && errno == ENOMEM) {
+ decoding_error ();
+ return false;
+ }
+ errno_assert (rc == 0);
+
+ next_step (tmpbuf, 1, &decoder_t::flags_ready);
+ return true;
+}
+
+bool zmq::decoder_t::flags_ready ()
+{
+ // Store the flags from the wire into the message structure.
+ in_progress.flags = tmpbuf [0];
+
+ next_step (zmq_msg_data (&in_progress), zmq_msg_size (&in_progress),
+ &decoder_t::message_ready);
+
+ return true;
+}
+
+bool zmq::decoder_t::message_ready ()
+{
+ // Message is completely read. Push it further and start reading
+ // new message. (in_progress is a 0-byte message after this point.)
+ if (!destination || !destination->write (&in_progress))
+ return false;
+
+ next_step (tmpbuf, 1, &decoder_t::one_byte_size_ready);
+ return true;
+}