Rename type zmq_monitor_fn -> zmq_monitor for a more natural callback definition API (zmq_monitor type, monitor.function callback)

The current ZMQ_MONITOR code does not compile in gcc 4.7, as -pedantic
and -Werror are enabled, and ISO C++ doesn't allow casting between
normal pointers (void*) and function pointers, as pedantically their
size could be different. This caused the library not compilable. This
commit workaround the problem by introducing one more indirection, i.e.
instead of calling

    (void *)listener

which is an error, we have to use

    *(void **)&listener

which is an undefined behavior :) but works on most platforms

Also, `optval_ = monitor` will not set the parameter in getsockopt(),
and the extra casting caused the LHS to be an rvalue which again makes
the code not compilable. The proper way is to pass a pointer of function
pointer and assign with indirection, i.e. `*optval_ = monitor`.

Also, fixed an asciidoc error in zmq_getsockopt.txt because the `~~~~`
is too long.

Assign arbitrary number of filters that will be applied for each new TCP transport
connection on a listening socket.
If no filters applied, then TCP transport allows connections from any ip.
If at least one filter is applied then new connection source ip should be matched.
To clear all filters call zmq_setsockopt(socket, ZMQ_TCP_ACCEPT_FILTER, NULL, 0).
Filter is a null-terminated string with ipv6 or ipv4 CIDR.

For example:
localhost
127.0.0.1
mail.ru/24
::1
::1/128
3ffe:1::
3ffe:1::/56

Returns -1 if the filter couldn't be assigned(format error or ipv6 filter with ZMQ_IPV4ONLY set)

P.S.
The only thing that worries me is that I had to re-enable 'default assign by reference constructor/operator'
for 'tcp_address_t' (and for my inherited class tcp_address_mask_t) to store it in std::vector in 'options_t'...

currently not fully cross-platform
work on linux
possibly work in *bsd
and could be enhanced to work on windows

Add value -1 to the ZMQ_RECONNECT_IVL to disable the reconnection algorithm

* Implemented new ctx API (_new, _destroy, _get, _set)
* Removed 'typesafe' macros from zmq.h
* Added support for MAX_SOCKETS (was tied into change for #337)
* Created new man pages

However, the "durable socket" behaviour wasn't re-added.
Identities are used solely for routing in REQ/REP pattern.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

This patch is meant to prevent users from running out of memory
when using 0MQ in the default configuration.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

At this point option exists, is documented and can be set,
however, it has no effect.
Signed-off-by: Steven McCoy <steven.mccoy@miru.hk>
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

This patch simplifies the whole codebase significantly,
including dropping depedency on libuuid.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

It was used only by ROUTER socket. After its removal it became
obsolete.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

The filtering is now done depending on the socket type. SUB socket
filters the messages (end-to-end filtering) while XSUB relies
on upstream nodes to do (imprefect) filtering.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

So far the requests in req/rep pattern were delivered to and processed
by worker even though the original requester was dead. Thus,
the worker processing replies with noone to deliver results to.
This optimisation drops requests in two situations:

1. Queued inbound requests in XREP socket when peer disconnects.
2. Queued outbound requests in XREQ when socket is closed.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

- Add doc and tests
- Add options and setup
- Wait using poll/select
Signed-off-by: Fabien Ninoles <fabien@tzone.org>
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

This option is a performance tweak. In devices XSUB socket filters
the messages just to send them to XPUB socket which filters them
once more. Setting ZMQ_FILTER option to 0 allows to switch the
filtering in XSUB socket off.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

So far, there was a pair of unidirectional pipes between a socket
and a session (or an inproc peer). This resulted in complex
problems with half-closed states and tracking which inpipe
corresponds to which outpipe.

This patch doesn't add any functionality in itself, but is
essential for further work on features like subscription
forwarding.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Sets the time-to-live field in every multicast packet sent from the socket.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

This patch addresses serveral issues:
1. It gathers message related functionality scattered over whole
   codebase into a single class.
2. It makes zmq_msg_t an opaque datatype. Internals of the class
   don't pollute zmq.h header file.
3. zmq_msg_t size decreases from 48 to 32 bytes. That saves ~33%
   of memory in scenarios with large amount of small messages.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

These new options allow to control the maximum size of the
inbound and outbound message pipe separately.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

This mimics POSIX specification.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

There's only one option now -- ZMQ_RECOVRY_IVL --
and it's measured in milliseconds.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

On-disk storage should be implemented in devices rather than
in 0MQ core. 0MQ is a networking library and there's no point
in storing network buffers on disk.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Multicast loopback is not a real multicast, rather a kernel-space
simulation. Moreover, it tends to be rather unreliable and lossy.
Removing the option will force users to use transports better
suited for the job, such as inproc or ipc.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

The new option allows user to guard against peers sending
oversized messages. Connection to peer sending oversized message
is dropped.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

It allows for exponential back-off strategy when reconnecting.
Signed-off-by: Thijs Terlouw <thijsterlouw@gmail.com>

For very high-speed message systems, the memory used for recovery can get to
be very large. The corrent limitation on that reduction is the ZMQ_RECOVERY_IVL
of 1 sec. I added in an additional option ZMQ_RECOVERY_IVL_MSEC, which is the
Recovery Interval in milliseconds. If used, this will override the previous
one, and allow you to set a sub-second recovery interval. If not set, the
default behavior is to use ZMQ_RECOVERY_IVL.
Signed-off-by: Bob Beaty <rbeaty@peak6.com>