src/core/sock.h

/*
    Copyright (c) 2012-2013 250bpm s.r.o.  All rights reserved.

    Permission is hereby granted, free of charge, to any person obtaining a copy
    of this software and associated documentation files (the "Software"),
    to deal in the Software without restriction, including without limitation
    the rights to use, copy, modify, merge, publish, distribute, sublicense,
    and/or sell copies of the Software, and to permit persons to whom
    the Software is furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included
    in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
    IN THE SOFTWARE.
*/

#ifndef NN_SOCK_INCLUDED
#define NN_SOCK_INCLUDED

#include "../protocol.h"
#include "../transport.h"

#include "../aio/ctx.h"
#include "../aio/fsm.h"

#include "../utils/efd.h"
#include "../utils/sem.h"
#include "../utils/clock.h"
#include "../utils/list.h"

struct nn_pipe;

/*  The maximum implemented transport ID. */
#define NN_MAX_TRANSPORT 3

struct nn_sock
{
    /*  Socket state machine. */
    struct nn_fsm fsm;
    int state;

    /*  Pointer to the instance of the specific socket type. */
    struct nn_sockbase *sockbase;

    /*  Pointer to the socket type metadata. */
    struct nn_socktype *socktype;

    int flags;

    struct nn_ctx ctx;
    struct nn_efd sndfd;
    struct nn_efd rcvfd;
    struct nn_sem termsem;

    /*  TODO: This clock can be accessed from different threads. If RDTSC
        is out-of-sync among different CPU cores, this can be a problem. */
    struct nn_clock clock;

    /*  List of all endpoints associated with the socket. */
    struct nn_list eps;

    /*  List of all endpoint being in the process of shutting down. */
    struct nn_list sdeps;

    /*  Next endpoint ID to assign to a new endpoint. */
    int eid;

    /*  Socket-level socket options. */
    int linger;
    int sndbuf;
    int rcvbuf;
    int sndtimeo;
    int rcvtimeo;
    int reconnect_ivl;
    int reconnect_ivl_max;
    int sndprio;
    int ipv4only;

    /*  Transport-specific socket options. */
    struct nn_optset *optsets [NN_MAX_TRANSPORT];
};

/*  Initialise the socket. */
int nn_sock_init (struct nn_sock *self, struct nn_socktype *socktype);

/*  Called by nn_close() to deallocate the socket. It's a blocking function
    and can return -EINTR. */
int nn_sock_term (struct nn_sock *self);

/*  Called by sockbase when stopping is done. */
void nn_sock_stopped (struct nn_sock *self);

/*  Called by nn_term() to let the socket know about the process shutdown. */
void nn_sock_zombify (struct nn_sock *self);

/*  Returns the AIO context associated with the socket. */
struct nn_ctx *nn_sock_getctx (struct nn_sock *self);

/*  Returns 1 if the specified socket type is a valid peer for this socket,
    0 otherwise. */
int nn_sock_ispeer (struct nn_sock *self, int socktype);

/*  Add new endpoint to the socket. */
int nn_sock_add_ep (struct nn_sock *self, struct nn_transport *transport,
    int bind, const char *addr);

/*  Remove the endpoint with the specified ID from the socket. */
int nn_sock_rm_ep (struct nn_sock *self, int eid);

/*  Send a message to the socket. */
int nn_sock_send (struct nn_sock *self, struct nn_msg *msg, int flags);

/*  Receive a message from the socket. */
int nn_sock_recv (struct nn_sock *self, struct nn_msg *msg, int flags);

/*  Set a socket option. */
int nn_sock_setopt (struct nn_sock *self, int level, int option,
    const void *optval, size_t optvallen); 

/*  Retrieve a socket option. This function is to be called from the API. */
int nn_sock_getopt (struct nn_sock *self, int level, int option,
    void *optval, size_t *optvallen);

/*  Retrieve a socket option. This function is to be called from within
    the socket. */
int nn_sock_getopt_inner (struct nn_sock *self, int level, int option,
    void *optval, size_t *optvallen);

/*  Used by pipes. */
int nn_sock_add (struct nn_sock *self, struct nn_pipe *pipe);
void nn_sock_rm (struct nn_sock *self, struct nn_pipe *pipe);

#endif