/*
Copyright (c) 2007-2015 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/>.
*/
#ifndef __ZMQ_CTX_HPP_INCLUDED__
#define __ZMQ_CTX_HPP_INCLUDED__
#include <map>
#include <vector>
#include <string>
#include <stdarg.h>
#include "mailbox.hpp"
#include "array.hpp"
#include "config.hpp"
#include "mutex.hpp"
#include "stdint.hpp"
#include "options.hpp"
#include "atomic_counter.hpp"
#include "thread.hpp"
namespace zmq
{
class object_t;
class io_thread_t;
class socket_base_t;
class reaper_t;
class pipe_t;
// Information associated with inproc endpoint. Note that endpoint options
// are registered as well so that the peer can access them without a need
// for synchronisation, handshaking or similar.
struct endpoint_t
{
socket_base_t *socket;
options_t options;
};
// Context object encapsulates all the global state associated with
// the library.
class ctx_t
{
public:
// Create the context object.
ctx_t ();
// Returns false if object is not a context.
bool check_tag ();
// This function is called when user invokes zmq_term. If there are
// no more sockets open it'll cause all the infrastructure to be shut
// down. If there are open sockets still, the deallocation happens
// after the last one is closed.
int terminate ();
// This function starts the terminate process by unblocking any blocking
// operations currently in progress and stopping any more socket activity
// (except zmq_close).
// This function is non-blocking.
// terminate must still be called afterwards.
// This function is optional, terminate will unblock any current
// operations as well.
int shutdown();
// Set and get context properties.
int set (int option_, int optval_);
int get (int option_);
// Create and destroy a socket.
zmq::socket_base_t *create_socket (int type_);
void destroy_socket (zmq::socket_base_t *socket_);
// Start a new thread with proper scheduling parameters.
void start_thread (thread_t &thread_, thread_fn *tfn_, void *arg_) const;
// Send command to the destination thread.
void send_command (uint32_t tid_, const command_t &command_);
// Returns the I/O thread that is the least busy at the moment.
// Affinity specifies which I/O threads are eligible (0 = all).
// Returns NULL if no I/O thread is available.
zmq::io_thread_t *choose_io_thread (uint64_t affinity_);
// Returns reaper thread object.
zmq::object_t *get_reaper ();
// Management of inproc endpoints.
int register_endpoint (const char *addr_, const endpoint_t &endpoint_);
int unregister_endpoint (const std::string &addr_, socket_base_t *socket_);
void unregister_endpoints (zmq::socket_base_t *socket_);
endpoint_t find_endpoint (const char *addr_);
void pend_connection (const std::string &addr_,
const endpoint_t &endpoint_, pipe_t **pipes_);
void connect_pending (const char *addr_, zmq::socket_base_t *bind_socket_);
enum {
term_tid = 0,
reaper_tid = 1
};
~ctx_t ();
private:
struct pending_connection_t
{
endpoint_t endpoint;
pipe_t* connect_pipe;
pipe_t* bind_pipe;
};
// Used to check whether the object is a context.
uint32_t tag;
// Sockets belonging to this context. We need the list so that
// we can notify the sockets when zmq_term() is called. The sockets
// will return ETERM then.
typedef array_t <socket_base_t> sockets_t;
sockets_t sockets;
// List of unused thread slots.
typedef std::vector <uint32_t> empty_slots_t;
empty_slots_t empty_slots;
// If true, zmq_init has been called but no socket has been created
// yet. Launching of I/O threads is delayed.
bool starting;
// If true, zmq_term was already called.
bool terminating;
// Synchronisation of accesses to global slot-related data:
// sockets, empty_slots, terminating. It also synchronises
// access to zombie sockets as such (as opposed to slots) and provides
// a memory barrier to ensure that all CPU cores see the same data.
mutex_t slot_sync;
// The reaper thread.
zmq::reaper_t *reaper;
// I/O threads.
typedef std::vector <zmq::io_thread_t*> io_threads_t;
io_threads_t io_threads;
// Array of pointers to mailboxes for both application and I/O threads.
uint32_t slot_count;
i_mailbox **slots;
// Mailbox for zmq_term thread.
mailbox_t term_mailbox;
// List of inproc endpoints within this context.
typedef std::map <std::string, endpoint_t> endpoints_t;
endpoints_t endpoints;
// List of inproc connection endpoints pending a bind
typedef std::multimap <std::string, pending_connection_t> pending_connections_t;
pending_connections_t pending_connections;
// Synchronisation of access to the list of inproc endpoints.
mutex_t endpoints_sync;
// Maximum socket ID.
static atomic_counter_t max_socket_id;
// Maximum number of sockets that can be opened at the same time.
int max_sockets;
// Number of I/O threads to launch.
int io_thread_count;
// Does context wait (possibly forever) on termination?
bool blocky;
// Is IPv6 enabled on this context?
bool ipv6;
// Thread scheduling parameters.
int thread_priority;
int thread_sched_policy;
// Synchronisation of access to context options.
mutex_t opt_sync;
ctx_t (const ctx_t&);
const ctx_t &operator = (const ctx_t&);
#ifdef HAVE_FORK
// the process that created this context. Used to detect forking.
pid_t pid;
#endif
enum side { connect_side, bind_side };
void connect_inproc_sockets(zmq::socket_base_t *bind_socket_, options_t& bind_options, const pending_connection_t &pending_connection_, side side_);
};
}
#endif