diff options
author | Micah Anderson <micah@riseup.net> | 2014-08-11 16:30:52 -0400 |
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committer | Micah Anderson <micah@riseup.net> | 2014-08-11 16:30:52 -0400 |
commit | 686958a9db9b140c9665af8fd001e7032a37a46e (patch) | |
tree | c0f1a7b4f7d1ffc12ce54271da73edefee18e5b6 /src/v2_decoder.cpp |
initial debian package import
Diffstat (limited to 'src/v2_decoder.cpp')
-rw-r--r-- | src/v2_decoder.cpp | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/src/v2_decoder.cpp b/src/v2_decoder.cpp new file mode 100644 index 0000000..a4f36e9 --- /dev/null +++ b/src/v2_decoder.cpp @@ -0,0 +1,142 @@ +/* + Copyright (c) 2007-2013 Contributors as noted in the AUTHORS file + + This file is part of 0MQ. + + 0MQ is free software; you can redistribute it and/or modify it under + the terms of the GNU Lesser 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 + GNU Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include <stdlib.h> +#include <string.h> + +#include "platform.hpp" +#ifdef ZMQ_HAVE_WINDOWS +#include "windows.hpp" +#endif + +#include "v2_protocol.hpp" +#include "v2_decoder.hpp" +#include "likely.hpp" +#include "wire.hpp" +#include "err.hpp" + +zmq::v2_decoder_t::v2_decoder_t (size_t bufsize_, int64_t maxmsgsize_) : + decoder_base_t <v2_decoder_t> (bufsize_), + msg_flags (0), + maxmsgsize (maxmsgsize_) +{ + int rc = in_progress.init (); + errno_assert (rc == 0); + + // At the beginning, read one byte and go to flags_ready state. + next_step (tmpbuf, 1, &v2_decoder_t::flags_ready); +} + +zmq::v2_decoder_t::~v2_decoder_t () +{ + int rc = in_progress.close (); + errno_assert (rc == 0); +} + +int zmq::v2_decoder_t::flags_ready () +{ + msg_flags = 0; + if (tmpbuf [0] & v2_protocol_t::more_flag) + msg_flags |= msg_t::more; + if (tmpbuf [0] & v2_protocol_t::command_flag) + msg_flags |= msg_t::command; + + // The payload length is either one or eight bytes, + // depending on whether the 'large' bit is set. + if (tmpbuf [0] & v2_protocol_t::large_flag) + next_step (tmpbuf, 8, &v2_decoder_t::eight_byte_size_ready); + else + next_step (tmpbuf, 1, &v2_decoder_t::one_byte_size_ready); + + return 0; +} + +int zmq::v2_decoder_t::one_byte_size_ready () +{ + // Message size must not exceed the maximum allowed size. + if (maxmsgsize >= 0) + if (unlikely (tmpbuf [0] > static_cast <uint64_t> (maxmsgsize))) { + errno = EMSGSIZE; + return -1; + } + + // 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 = in_progress.init_size (tmpbuf [0]); + if (unlikely (rc)) { + errno_assert (errno == ENOMEM); + rc = in_progress.init (); + errno_assert (rc == 0); + errno = ENOMEM; + return -1; + } + + in_progress.set_flags (msg_flags); + next_step (in_progress.data (), in_progress.size (), + &v2_decoder_t::message_ready); + + return 0; +} + +int zmq::v2_decoder_t::eight_byte_size_ready () +{ + // The payload size is encoded as 64-bit unsigned integer. + // The most significant byte comes first. + const uint64_t msg_size = get_uint64 (tmpbuf); + + // Message size must not exceed the maximum allowed size. + if (maxmsgsize >= 0) + if (unlikely (msg_size > static_cast <uint64_t> (maxmsgsize))) { + errno = EMSGSIZE; + return -1; + } + + // Message size must fit into size_t data type. + if (unlikely (msg_size != static_cast <size_t> (msg_size))) { + errno = EMSGSIZE; + return -1; + } + + // in_progress is initialised at this point so in theory we should + // close it before calling init_size, however, it's a 0-byte + // message and thus we can treat it as uninitialised. + int rc = in_progress.init_size (static_cast <size_t> (msg_size)); + if (unlikely (rc)) { + errno_assert (errno == ENOMEM); + rc = in_progress.init (); + errno_assert (rc == 0); + errno = ENOMEM; + return -1; + } + + in_progress.set_flags (msg_flags); + next_step (in_progress.data (), in_progress.size (), + &v2_decoder_t::message_ready); + + return 0; +} + +int zmq::v2_decoder_t::message_ready () +{ + // Message is completely read. Signal this to the caller + // and prepare to decode next message. + next_step (tmpbuf, 1, &v2_decoder_t::flags_ready); + return 1; +} |