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mirror of https://github.com/zeromq/libzmq.git synced 2024-12-29 00:32:34 +08:00
libzmq/src/zmq.cpp
2014-07-12 09:01:27 -05:00

1085 lines
29 KiB
C++

/*
Copyright (c) 2007-2014 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/>.
*/
#define ZMQ_TYPE_UNSAFE
#include "poller.hpp"
// On AIX platform, poll.h has to be included first to get consistent
// definition of pollfd structure (AIX uses 'reqevents' and 'retnevents'
// instead of 'events' and 'revents' and defines macros to map from POSIX-y
// names to AIX-specific names).
#if defined ZMQ_POLL_BASED_ON_POLL
#include <poll.h>
#endif
// zmq.h must be included *after* poll.h for AIX to build properly
#include "../include/zmq.h"
#if defined ZMQ_HAVE_WINDOWS
#include "windows.hpp"
#else
#include <unistd.h>
#endif
// XSI vector I/O
#if defined ZMQ_HAVE_UIO
#include <sys/uio.h>
#else
struct iovec {
void *iov_base;
size_t iov_len;
};
#endif
#include <string.h>
#include <stdlib.h>
#include <new>
#include "proxy.hpp"
#include "socket_base.hpp"
#include "stdint.hpp"
#include "config.hpp"
#include "likely.hpp"
#include "clock.hpp"
#include "ctx.hpp"
#include "err.hpp"
#include "msg.hpp"
#include "fd.hpp"
#include "metadata.hpp"
#if !defined ZMQ_HAVE_WINDOWS
#include <unistd.h>
#endif
#if defined ZMQ_HAVE_OPENPGM
#define __PGM_WININT_H__
#include <pgm/pgm.h>
#endif
// Compile time check whether msg_t fits into zmq_msg_t.
typedef char check_msg_t_size
[sizeof (zmq::msg_t) == sizeof (zmq_msg_t) ? 1 : -1];
void zmq_version (int *major_, int *minor_, int *patch_)
{
*major_ = ZMQ_VERSION_MAJOR;
*minor_ = ZMQ_VERSION_MINOR;
*patch_ = ZMQ_VERSION_PATCH;
}
const char *zmq_strerror (int errnum_)
{
return zmq::errno_to_string (errnum_);
}
int zmq_errno (void)
{
return errno;
}
// New context API
void *zmq_ctx_new (void)
{
#if defined ZMQ_HAVE_OPENPGM
// Init PGM transport. Ensure threading and timer are enabled. Find PGM
// protocol ID. Note that if you want to use gettimeofday and sleep for
// openPGM timing, set environment variables PGM_TIMER to "GTOD" and
// PGM_SLEEP to "USLEEP".
pgm_error_t *pgm_error = NULL;
const bool ok = pgm_init (&pgm_error);
if (ok != TRUE) {
// Invalid parameters don't set pgm_error_t
zmq_assert (pgm_error != NULL);
if (pgm_error->domain == PGM_ERROR_DOMAIN_TIME && (
pgm_error->code == PGM_ERROR_FAILED)) {
// Failed to access RTC or HPET device.
pgm_error_free (pgm_error);
errno = EINVAL;
return NULL;
}
// PGM_ERROR_DOMAIN_ENGINE: WSAStartup errors or missing WSARecvMsg.
zmq_assert (false);
}
#endif
#ifdef ZMQ_HAVE_WINDOWS
// Intialise Windows sockets. Note that WSAStartup can be called multiple
// times given that WSACleanup will be called for each WSAStartup.
// We do this before the ctx constructor since its embedded mailbox_t
// object needs Winsock to be up and running.
WORD version_requested = MAKEWORD (2, 2);
WSADATA wsa_data;
int rc = WSAStartup (version_requested, &wsa_data);
zmq_assert (rc == 0);
zmq_assert (LOBYTE (wsa_data.wVersion) == 2 &&
HIBYTE (wsa_data.wVersion) == 2);
#endif
// Create 0MQ context.
zmq::ctx_t *ctx = new (std::nothrow) zmq::ctx_t;
alloc_assert (ctx);
return ctx;
}
int zmq_ctx_term (void *ctx_)
{
if (!ctx_ || !((zmq::ctx_t*) ctx_)->check_tag ()) {
errno = EFAULT;
return -1;
}
int rc = ((zmq::ctx_t*) ctx_)->terminate ();
int en = errno;
// Shut down only if termination was not interrupted by a signal.
if (!rc || en != EINTR) {
#ifdef ZMQ_HAVE_WINDOWS
// On Windows, uninitialise socket layer.
rc = WSACleanup ();
wsa_assert (rc != SOCKET_ERROR);
#endif
#if defined ZMQ_HAVE_OPENPGM
// Shut down the OpenPGM library.
if (pgm_shutdown () != TRUE)
zmq_assert (false);
#endif
}
errno = en;
return rc;
}
int zmq_ctx_shutdown (void *ctx_)
{
if (!ctx_ || !((zmq::ctx_t*) ctx_)->check_tag ()) {
errno = EFAULT;
return -1;
}
return ((zmq::ctx_t*) ctx_)->shutdown ();
}
int zmq_ctx_set (void *ctx_, int option_, int optval_)
{
if (!ctx_ || !((zmq::ctx_t*) ctx_)->check_tag ()) {
errno = EFAULT;
return -1;
}
return ((zmq::ctx_t*) ctx_)->set (option_, optval_);
}
int zmq_ctx_get (void *ctx_, int option_)
{
if (!ctx_ || !((zmq::ctx_t*) ctx_)->check_tag ()) {
errno = EFAULT;
return -1;
}
return ((zmq::ctx_t*) ctx_)->get (option_);
}
// Stable/legacy context API
void *zmq_init (int io_threads_)
{
if (io_threads_ >= 0) {
void *ctx = zmq_ctx_new ();
zmq_ctx_set (ctx, ZMQ_IO_THREADS, io_threads_);
return ctx;
}
errno = EINVAL;
return NULL;
}
int zmq_term (void *ctx_)
{
return zmq_ctx_term (ctx_);
}
int zmq_ctx_destroy (void *ctx_)
{
return zmq_ctx_term (ctx_);
}
// Sockets
void *zmq_socket (void *ctx_, int type_)
{
if (!ctx_ || !((zmq::ctx_t*) ctx_)->check_tag ()) {
errno = EFAULT;
return NULL;
}
zmq::ctx_t *ctx = (zmq::ctx_t*) ctx_;
zmq::socket_base_t *s = ctx->create_socket (type_);
return (void *) s;
}
int zmq_close (void *s_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
((zmq::socket_base_t*) s_)->close ();
return 0;
}
int zmq_setsockopt (void *s_, int option_, const void *optval_,
size_t optvallen_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
int result = s->setsockopt (option_, optval_, optvallen_);
return result;
}
int zmq_getsockopt (void *s_, int option_, void *optval_, size_t *optvallen_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
int result = s->getsockopt (option_, optval_, optvallen_);
return result;
}
int zmq_socket_monitor (void *s_, const char *addr_, int events_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
int result = s->monitor (addr_, events_);
return result;
}
int zmq_bind (void *s_, const char *addr_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
int result = s->bind (addr_);
return result;
}
int zmq_connect (void *s_, const char *addr_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
int result = s->connect (addr_);
return result;
}
int zmq_unbind (void *s_, const char *addr_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
return s->term_endpoint (addr_);
}
int zmq_disconnect (void *s_, const char *addr_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
return s->term_endpoint (addr_);
}
// Sending functions.
static int
s_sendmsg (zmq::socket_base_t *s_, zmq_msg_t *msg_, int flags_)
{
int sz = (int) zmq_msg_size (msg_);
int rc = s_->send ((zmq::msg_t*) msg_, flags_);
if (unlikely (rc < 0))
return -1;
return sz;
}
/* To be deprecated once zmq_msg_send() is stable */
int zmq_sendmsg (void *s_, zmq_msg_t *msg_, int flags_)
{
return zmq_msg_send (msg_, s_, flags_);
}
int zmq_send (void *s_, const void *buf_, size_t len_, int flags_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq_msg_t msg;
int rc = zmq_msg_init_size (&msg, len_);
if (rc != 0)
return -1;
memcpy (zmq_msg_data (&msg), buf_, len_);
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
rc = s_sendmsg (s, &msg, flags_);
if (unlikely (rc < 0)) {
int err = errno;
int rc2 = zmq_msg_close (&msg);
errno_assert (rc2 == 0);
errno = err;
return -1;
}
// Note the optimisation here. We don't close the msg object as it is
// empty anyway. This may change when implementation of zmq_msg_t changes.
return rc;
}
int zmq_send_const (void *s_, const void *buf_, size_t len_, int flags_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq_msg_t msg;
int rc = zmq_msg_init_data (&msg, (void*)buf_, len_, NULL, NULL);
if (rc != 0)
return -1;
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
rc = s_sendmsg (s, &msg, flags_);
if (unlikely (rc < 0)) {
int err = errno;
int rc2 = zmq_msg_close (&msg);
errno_assert (rc2 == 0);
errno = err;
return -1;
}
// Note the optimisation here. We don't close the msg object as it is
// empty anyway. This may change when implementation of zmq_msg_t changes.
return rc;
}
// Send multiple messages.
// TODO: this function has no man page
//
// If flag bit ZMQ_SNDMORE is set the vector is treated as
// a single multi-part message, i.e. the last message has
// ZMQ_SNDMORE bit switched off.
//
int zmq_sendiov (void *s_, iovec *a_, size_t count_, int flags_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
int rc = 0;
zmq_msg_t msg;
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
for (size_t i = 0; i < count_; ++i) {
rc = zmq_msg_init_size (&msg, a_[i].iov_len);
if (rc != 0) {
rc = -1;
break;
}
memcpy (zmq_msg_data (&msg), a_[i].iov_base, a_[i].iov_len);
if (i == count_ - 1)
flags_ = flags_ & ~ZMQ_SNDMORE;
rc = s_sendmsg (s, &msg, flags_);
if (unlikely (rc < 0)) {
int err = errno;
int rc2 = zmq_msg_close (&msg);
errno_assert (rc2 == 0);
errno = err;
rc = -1;
break;
}
}
return rc;
}
// Receiving functions.
static int
s_recvmsg (zmq::socket_base_t *s_, zmq_msg_t *msg_, int flags_)
{
int rc = s_->recv ((zmq::msg_t*) msg_, flags_);
if (unlikely (rc < 0))
return -1;
return (int) zmq_msg_size (msg_);
}
/* To be deprecated once zmq_msg_recv() is stable */
int zmq_recvmsg (void *s_, zmq_msg_t *msg_, int flags_)
{
return zmq_msg_recv (msg_, s_, flags_);
}
int zmq_recv (void *s_, void *buf_, size_t len_, int flags_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq_msg_t msg;
int rc = zmq_msg_init (&msg);
errno_assert (rc == 0);
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
int nbytes = s_recvmsg (s, &msg, flags_);
if (unlikely (nbytes < 0)) {
int err = errno;
rc = zmq_msg_close (&msg);
errno_assert (rc == 0);
errno = err;
return -1;
}
// At the moment an oversized message is silently truncated.
// TODO: Build in a notification mechanism to report the overflows.
size_t to_copy = size_t (nbytes) < len_ ? size_t (nbytes) : len_;
memcpy (buf_, zmq_msg_data (&msg), to_copy);
rc = zmq_msg_close (&msg);
errno_assert (rc == 0);
return nbytes;
}
// Receive a multi-part message
//
// Receives up to *count_ parts of a multi-part message.
// Sets *count_ to the actual number of parts read.
// ZMQ_RCVMORE is set to indicate if a complete multi-part message was read.
// Returns number of message parts read, or -1 on error.
//
// Note: even if -1 is returned, some parts of the message
// may have been read. Therefore the client must consult
// *count_ to retrieve message parts successfully read,
// even if -1 is returned.
//
// The iov_base* buffers of each iovec *a_ filled in by this
// function may be freed using free().
// TODO: this function has no man page
//
int zmq_recviov (void *s_, iovec *a_, size_t *count_, int flags_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
size_t count = *count_;
int nread = 0;
bool recvmore = true;
*count_ = 0;
for (size_t i = 0; recvmore && i < count; ++i) {
zmq_msg_t msg;
int rc = zmq_msg_init (&msg);
errno_assert (rc == 0);
int nbytes = s_recvmsg (s, &msg, flags_);
if (unlikely (nbytes < 0)) {
int err = errno;
rc = zmq_msg_close (&msg);
errno_assert (rc == 0);
errno = err;
nread = -1;
break;
}
a_[i].iov_len = zmq_msg_size (&msg);
a_[i].iov_base = static_cast<char *> (malloc(a_[i].iov_len));
if (unlikely (!a_[i].iov_base)) {
errno = ENOMEM;
return -1;
}
memcpy(a_[i].iov_base,static_cast<char *> (zmq_msg_data (&msg)),
a_[i].iov_len);
// Assume zmq_socket ZMQ_RVCMORE is properly set.
recvmore = ((zmq::msg_t*) (void *) &msg)->flags () & zmq::msg_t::more;
rc = zmq_msg_close(&msg);
errno_assert (rc == 0);
++*count_;
++nread;
}
return nread;
}
// Message manipulators.
int zmq_msg_init (zmq_msg_t *msg_)
{
return ((zmq::msg_t*) msg_)->init ();
}
int zmq_msg_init_size (zmq_msg_t *msg_, size_t size_)
{
return ((zmq::msg_t*) msg_)->init_size (size_);
}
int zmq_msg_init_data (zmq_msg_t *msg_, void *data_, size_t size_,
zmq_free_fn *ffn_, void *hint_)
{
return ((zmq::msg_t*) msg_)->init_data (data_, size_, ffn_, hint_);
}
int zmq_msg_send (zmq_msg_t *msg_, void *s_, int flags_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
int result = s_sendmsg (s, msg_, flags_);
return result;
}
int zmq_msg_recv (zmq_msg_t *msg_, void *s_, int flags_)
{
if (!s_ || !((zmq::socket_base_t*) s_)->check_tag ()) {
errno = ENOTSOCK;
return -1;
}
zmq::socket_base_t *s = (zmq::socket_base_t *) s_;
int result = s_recvmsg (s, msg_, flags_);
return result;
}
int zmq_msg_close (zmq_msg_t *msg_)
{
return ((zmq::msg_t*) msg_)->close ();
}
int zmq_msg_move (zmq_msg_t *dest_, zmq_msg_t *src_)
{
return ((zmq::msg_t*) dest_)->move (*(zmq::msg_t*) src_);
}
int zmq_msg_copy (zmq_msg_t *dest_, zmq_msg_t *src_)
{
return ((zmq::msg_t*) dest_)->copy (*(zmq::msg_t*) src_);
}
void *zmq_msg_data (zmq_msg_t *msg_)
{
return ((zmq::msg_t*) msg_)->data ();
}
size_t zmq_msg_size (zmq_msg_t *msg_)
{
return ((zmq::msg_t*) msg_)->size ();
}
int zmq_msg_more (zmq_msg_t *msg_)
{
return zmq_msg_get (msg_, ZMQ_MORE);
}
int zmq_msg_get (zmq_msg_t *msg_, int property_)
{
switch (property_) {
case ZMQ_MORE:
return (((zmq::msg_t*) msg_)->flags () & zmq::msg_t::more)? 1: 0;
case ZMQ_SRCFD:
// warning: int64_t to int
return ((zmq::msg_t*) msg_)->fd ();
case ZMQ_SHARED:
return (((zmq::msg_t*) msg_)->flags () & zmq::msg_t::shared)? 1: 0;
default:
errno = EINVAL;
return -1;
}
}
int zmq_msg_set (zmq_msg_t *, int, int)
{
// No properties supported at present
errno = EINVAL;
return -1;
}
// Get message metadata string
const char *zmq_msg_gets (zmq_msg_t *msg_, const char *property_)
{
zmq::metadata_t *metadata = ((zmq::msg_t*) msg_)->metadata ();
const char *value = NULL;
if (metadata)
value = metadata->get (std::string (property_));
if (value)
return value;
else {
errno = EINVAL;
return NULL;
}
}
// Polling.
int zmq_poll (zmq_pollitem_t *items_, int nitems_, long timeout_)
{
#if defined ZMQ_POLL_BASED_ON_POLL
if (unlikely (nitems_ < 0)) {
errno = EINVAL;
return -1;
}
if (unlikely (nitems_ == 0)) {
if (timeout_ == 0)
return 0;
#if defined ZMQ_HAVE_WINDOWS
Sleep (timeout_ > 0 ? timeout_ : INFINITE);
return 0;
#elif defined ZMQ_HAVE_ANDROID
usleep (timeout_ * 1000);
return 0;
#else
return usleep (timeout_ * 1000);
#endif
}
if (!items_) {
errno = EFAULT;
return -1;
}
zmq::clock_t clock;
uint64_t now = 0;
uint64_t end = 0;
pollfd spollfds[ZMQ_POLLITEMS_DFLT];
pollfd *pollfds = spollfds;
if (nitems_ > ZMQ_POLLITEMS_DFLT) {
pollfds = (pollfd*) malloc (nitems_ * sizeof (pollfd));
alloc_assert (pollfds);
}
// Build pollset for poll () system call.
for (int i = 0; i != nitems_; i++) {
// If the poll item is a 0MQ socket, we poll on the file descriptor
// retrieved by the ZMQ_FD socket option.
if (items_ [i].socket) {
size_t zmq_fd_size = sizeof (zmq::fd_t);
if (zmq_getsockopt (items_ [i].socket, ZMQ_FD, &pollfds [i].fd,
&zmq_fd_size) == -1) {
if (pollfds != spollfds)
free (pollfds);
return -1;
}
pollfds [i].events = items_ [i].events ? POLLIN : 0;
}
// Else, the poll item is a raw file descriptor. Just convert the
// events to normal POLLIN/POLLOUT for poll ().
else {
pollfds [i].fd = items_ [i].fd;
pollfds [i].events =
(items_ [i].events & ZMQ_POLLIN ? POLLIN : 0) |
(items_ [i].events & ZMQ_POLLOUT ? POLLOUT : 0);
}
}
bool first_pass = true;
int nevents = 0;
while (true) {
// Compute the timeout for the subsequent poll.
int timeout;
if (first_pass)
timeout = 0;
else
if (timeout_ < 0)
timeout = -1;
else
timeout = end - now;
// Wait for events.
while (true) {
int rc = poll (pollfds, nitems_, timeout);
if (rc == -1 && errno == EINTR) {
if (pollfds != spollfds)
free (pollfds);
return -1;
}
errno_assert (rc >= 0);
break;
}
// Check for the events.
for (int i = 0; i != nitems_; i++) {
items_ [i].revents = 0;
// The poll item is a 0MQ socket. Retrieve pending events
// using the ZMQ_EVENTS socket option.
if (items_ [i].socket) {
size_t zmq_events_size = sizeof (uint32_t);
uint32_t zmq_events;
if (zmq_getsockopt (items_ [i].socket, ZMQ_EVENTS, &zmq_events,
&zmq_events_size) == -1) {
if (pollfds != spollfds)
free (pollfds);
return -1;
}
if ((items_ [i].events & ZMQ_POLLOUT) &&
(zmq_events & ZMQ_POLLOUT))
items_ [i].revents |= ZMQ_POLLOUT;
if ((items_ [i].events & ZMQ_POLLIN) &&
(zmq_events & ZMQ_POLLIN))
items_ [i].revents |= ZMQ_POLLIN;
}
// Else, the poll item is a raw file descriptor, simply convert
// the events to zmq_pollitem_t-style format.
else {
if (pollfds [i].revents & POLLIN)
items_ [i].revents |= ZMQ_POLLIN;
if (pollfds [i].revents & POLLOUT)
items_ [i].revents |= ZMQ_POLLOUT;
if (pollfds [i].revents & ~(POLLIN | POLLOUT))
items_ [i].revents |= ZMQ_POLLERR;
}
if (items_ [i].revents)
nevents++;
}
// If timout is zero, exit immediately whether there are events or not.
if (timeout_ == 0)
break;
// If there are events to return, we can exit immediately.
if (nevents)
break;
// At this point we are meant to wait for events but there are none.
// If timeout is infinite we can just loop until we get some events.
if (timeout_ < 0) {
if (first_pass)
first_pass = false;
continue;
}
// The timeout is finite and there are no events. In the first pass
// we get a timestamp of when the polling have begun. (We assume that
// first pass have taken negligible time). We also compute the time
// when the polling should time out.
if (first_pass) {
now = clock.now_ms ();
end = now + timeout_;
if (now == end)
break;
first_pass = false;
continue;
}
// Find out whether timeout have expired.
now = clock.now_ms ();
if (now >= end)
break;
}
if (pollfds != spollfds)
free (pollfds);
return nevents;
#elif defined ZMQ_POLL_BASED_ON_SELECT
if (unlikely (nitems_ < 0)) {
errno = EINVAL;
return -1;
}
if (unlikely (nitems_ == 0)) {
if (timeout_ == 0)
return 0;
#if defined ZMQ_HAVE_WINDOWS
Sleep (timeout_ > 0 ? timeout_ : INFINITE);
return 0;
#else
return usleep (timeout_ * 1000);
#endif
}
zmq::clock_t clock;
uint64_t now = 0;
uint64_t end = 0;
// Ensure we do not attempt to select () on more than FD_SETSIZE
// file descriptors.
zmq_assert (nitems_ <= FD_SETSIZE);
fd_set pollset_in;
FD_ZERO (&pollset_in);
fd_set pollset_out;
FD_ZERO (&pollset_out);
fd_set pollset_err;
FD_ZERO (&pollset_err);
zmq::fd_t maxfd = 0;
// Build the fd_sets for passing to select ().
for (int i = 0; i != nitems_; i++) {
// If the poll item is a 0MQ socket we are interested in input on the
// notification file descriptor retrieved by the ZMQ_FD socket option.
if (items_ [i].socket) {
size_t zmq_fd_size = sizeof (zmq::fd_t);
zmq::fd_t notify_fd;
if (zmq_getsockopt (items_ [i].socket, ZMQ_FD, &notify_fd,
&zmq_fd_size) == -1)
return -1;
if (items_ [i].events) {
FD_SET (notify_fd, &pollset_in);
if (maxfd < notify_fd)
maxfd = notify_fd;
}
}
// Else, the poll item is a raw file descriptor. Convert the poll item
// events to the appropriate fd_sets.
else {
if (items_ [i].events & ZMQ_POLLIN)
FD_SET (items_ [i].fd, &pollset_in);
if (items_ [i].events & ZMQ_POLLOUT)
FD_SET (items_ [i].fd, &pollset_out);
if (items_ [i].events & ZMQ_POLLERR)
FD_SET (items_ [i].fd, &pollset_err);
if (maxfd < items_ [i].fd)
maxfd = items_ [i].fd;
}
}
bool first_pass = true;
int nevents = 0;
fd_set inset, outset, errset;
while (true) {
// Compute the timeout for the subsequent poll.
timeval timeout;
timeval *ptimeout;
if (first_pass) {
timeout.tv_sec = 0;
timeout.tv_usec = 0;
ptimeout = &timeout;
}
else
if (timeout_ < 0)
ptimeout = NULL;
else {
timeout.tv_sec = (long) ((end - now) / 1000);
timeout.tv_usec = (long) ((end - now) % 1000 * 1000);
ptimeout = &timeout;
}
// Wait for events. Ignore interrupts if there's infinite timeout.
while (true) {
memcpy (&inset, &pollset_in, sizeof (fd_set));
memcpy (&outset, &pollset_out, sizeof (fd_set));
memcpy (&errset, &pollset_err, sizeof (fd_set));
#if defined ZMQ_HAVE_WINDOWS
int rc = select (0, &inset, &outset, &errset, ptimeout);
if (unlikely (rc == SOCKET_ERROR)) {
errno = zmq::wsa_error_to_errno (WSAGetLastError ());
wsa_assert (errno == ENOTSOCK);
return -1;
}
#else
int rc = select (maxfd + 1, &inset, &outset, &errset, ptimeout);
if (unlikely (rc == -1)) {
errno_assert (errno == EINTR || errno == EBADF);
return -1;
}
#endif
break;
}
// Check for the events.
for (int i = 0; i != nitems_; i++) {
items_ [i].revents = 0;
// The poll item is a 0MQ socket. Retrieve pending events
// using the ZMQ_EVENTS socket option.
if (items_ [i].socket) {
size_t zmq_events_size = sizeof (uint32_t);
uint32_t zmq_events;
if (zmq_getsockopt (items_ [i].socket, ZMQ_EVENTS, &zmq_events,
&zmq_events_size) == -1)
return -1;
if ((items_ [i].events & ZMQ_POLLOUT) &&
(zmq_events & ZMQ_POLLOUT))
items_ [i].revents |= ZMQ_POLLOUT;
if ((items_ [i].events & ZMQ_POLLIN) &&
(zmq_events & ZMQ_POLLIN))
items_ [i].revents |= ZMQ_POLLIN;
}
// Else, the poll item is a raw file descriptor, simply convert
// the events to zmq_pollitem_t-style format.
else {
if (FD_ISSET (items_ [i].fd, &inset))
items_ [i].revents |= ZMQ_POLLIN;
if (FD_ISSET (items_ [i].fd, &outset))
items_ [i].revents |= ZMQ_POLLOUT;
if (FD_ISSET (items_ [i].fd, &errset))
items_ [i].revents |= ZMQ_POLLERR;
}
if (items_ [i].revents)
nevents++;
}
// If timout is zero, exit immediately whether there are events or not.
if (timeout_ == 0)
break;
// If there are events to return, we can exit immediately.
if (nevents)
break;
// At this point we are meant to wait for events but there are none.
// If timeout is infinite we can just loop until we get some events.
if (timeout_ < 0) {
if (first_pass)
first_pass = false;
continue;
}
// The timeout is finite and there are no events. In the first pass
// we get a timestamp of when the polling have begun. (We assume that
// first pass have taken negligible time). We also compute the time
// when the polling should time out.
if (first_pass) {
now = clock.now_ms ();
end = now + timeout_;
if (now == end)
break;
first_pass = false;
continue;
}
// Find out whether timeout have expired.
now = clock.now_ms ();
if (now >= end)
break;
}
return nevents;
#else
// Exotic platforms that support neither poll() nor select().
errno = ENOTSUP;
return -1;
#endif
}
// The proxy functionality
int zmq_proxy (void *frontend_, void *backend_, void *capture_)
{
if (!frontend_ || !backend_) {
errno = EFAULT;
return -1;
}
return zmq::proxy (
(zmq::socket_base_t*) frontend_,
(zmq::socket_base_t*) backend_,
(zmq::socket_base_t*) capture_);
}
int zmq_proxy_steerable (void *frontend_, void *backend_, void *capture_, void *control_)
{
if (!frontend_ || !backend_) {
errno = EFAULT;
return -1;
}
return zmq::proxy (
(zmq::socket_base_t*) frontend_,
(zmq::socket_base_t*) backend_,
(zmq::socket_base_t*) capture_,
(zmq::socket_base_t*) control_);
}
// The deprecated device functionality
int zmq_device (int /* type */, void *frontend_, void *backend_)
{
return zmq::proxy (
(zmq::socket_base_t*) frontend_,
(zmq::socket_base_t*) backend_, NULL);
}
// Probe library capabilities; for now, reports on transport and security
int zmq_has (const char *capability)
{
#if !defined (ZMQ_HAVE_WINDOWS) && !defined (ZMQ_HAVE_OPENVMS)
if (strcmp (capability, "ipc") == 0)
return true;
#endif
#if defined (ZMQ_HAVE_OPENPGM)
if (strcmp (capability, "pgm") == 0)
return true;
#endif
#if defined (ZMQ_HAVE_TIPC)
if (strcmp (capability, "tipc") == 0)
return true;
#endif
#if defined (ZMQ_HAVE_NORM)
if (strcmp (capability, "norm") == 0)
return true;
#endif
#if defined (HAVE_LIBSODIUM)
if (strcmp (capability, "curve") == 0)
return true;
#endif
#if defined (HAVE_LIBGSSAPI_KRB5)
if (strcmp (capability, "gssapi") == 0)
return true;
#endif
// Whatever the application asked for, we don't have
return false;
}