Imported Upstream version 2.1.3upstream/2.1.3

1 files changed, 382 insertions, 0 deletions

diff --git a/src/mailbox.cpp b/src/mailbox.cpp
new file mode 100644
index 0000000..221396b
--- /dev/null
+++ b/src/mailbox.cpp
@@ -0,0 +1,382 @@
+/*
+    Copyright (c) 2007-2011 iMatix Corporation
+    Copyright (c) 2007-2011 Other 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 "mailbox.hpp"
+#include "platform.hpp"
+#include "err.hpp"
+#include "fd.hpp"
+#include "ip.hpp"
+
+#if defined ZMQ_HAVE_WINDOWS
+#include "windows.hpp"
+#else
+#include <unistd.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <netinet/tcp.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#endif
+
+zmq::fd_t zmq::mailbox_t::get_fd ()
+{
+    return r;
+}
+
+#if defined ZMQ_HAVE_WINDOWS
+
+zmq::mailbox_t::mailbox_t ()
+{
+    //  Create the socketpair for signalling.
+    int rc = make_socketpair (&r, &w);
+    errno_assert (rc == 0);
+
+    //  Set the writer to non-blocking mode.
+    unsigned long argp = 1;
+    rc = ioctlsocket (w, FIONBIO, &argp);
+    wsa_assert (rc != SOCKET_ERROR);
+
+    //  Set the reader to non-blocking mode.
+    argp = 1;
+    rc = ioctlsocket (r, FIONBIO, &argp);
+    wsa_assert (rc != SOCKET_ERROR);
+}
+
+zmq::mailbox_t::~mailbox_t ()
+{
+    int rc = closesocket (w);
+    wsa_assert (rc != SOCKET_ERROR);
+
+    rc = closesocket (r);
+    wsa_assert (rc != SOCKET_ERROR);
+}
+
+void zmq::mailbox_t::send (const command_t &cmd_)
+{
+    //  TODO: Implement SNDBUF auto-resizing as for POSIX platforms.
+    //  In the mean time, the following code with assert if the send()
+    //  call would block.
+    int nbytes = ::send (w, (char *)&cmd_, sizeof (command_t), 0);
+    wsa_assert (nbytes != SOCKET_ERROR);
+    zmq_assert (nbytes == sizeof (command_t));
+}
+
+int zmq::mailbox_t::recv (command_t *cmd_, bool block_)
+{
+    //  If required, set the reader to blocking mode.
+    if (block_) {
+        unsigned long argp = 0;
+        int rc = ioctlsocket (r, FIONBIO, &argp);
+        wsa_assert (rc != SOCKET_ERROR);
+    }
+
+    //  Attempt to read an entire command. Returns EAGAIN if non-blocking
+    //  and a command is not available. Save value of errno if we wish to pass
+    //  it to caller.
+    int err = 0;
+    int nbytes = ::recv (r, (char *)cmd_, sizeof (command_t), 0);
+    if (nbytes == -1 && WSAGetLastError () == WSAEWOULDBLOCK)
+        err = EAGAIN;
+
+    //  Re-set the reader to non-blocking mode.
+    if (block_) {
+        unsigned long argp = 1;
+        int rc = ioctlsocket (r, FIONBIO, &argp);
+        wsa_assert (rc != SOCKET_ERROR);
+    }
+
+    //  If the recv failed, return with the saved errno.
+    if (err != 0) {
+        errno = err;
+        return -1;
+    }
+
+    //  Sanity check for success.
+    wsa_assert (nbytes != SOCKET_ERROR);
+
+    //  Check whether we haven't got half of command.
+    zmq_assert (nbytes == sizeof (command_t));
+
+    return 0;
+}
+
+#else
+
+zmq::mailbox_t::mailbox_t ()
+{
+#ifdef PIPE_BUF
+    //  Make sure that command can be written to the socket in atomic fashion.
+    //  If this wasn't guaranteed, commands from different threads would be
+    //  interleaved.
+    zmq_assert (sizeof (command_t) <= PIPE_BUF);
+#endif
+
+    //  Create the socketpair for signaling.
+    int rc = make_socketpair (&r, &w);
+    errno_assert (rc == 0);
+
+    //  Set the writer to non-blocking mode.
+    int flags = fcntl (w, F_GETFL, 0);
+    errno_assert (flags >= 0);
+    rc = fcntl (w, F_SETFL, flags | O_NONBLOCK);
+    errno_assert (rc == 0);
+
+#ifndef MSG_DONTWAIT
+    //  Set the reader to non-blocking mode.
+    flags = fcntl (r, F_GETFL, 0);
+    errno_assert (flags >= 0);
+    rc = fcntl (r, F_SETFL, flags | O_NONBLOCK);
+    errno_assert (rc == 0);
+#endif
+}
+
+zmq::mailbox_t::~mailbox_t ()
+{
+    close (w);
+    close (r);
+}
+
+void zmq::mailbox_t::send (const command_t &cmd_)
+{
+    //  Attempt to write an entire command without blocking.
+    ssize_t nbytes;
+    do {
+        nbytes = ::send (w, &cmd_, sizeof (command_t), 0);
+    } while (nbytes == -1 && errno == EINTR);
+
+    //  Attempt to increase mailbox SNDBUF if the send failed.
+    if (nbytes == -1 && errno == EAGAIN) {
+        int old_sndbuf, new_sndbuf;
+        socklen_t sndbuf_size = sizeof old_sndbuf;
+
+        //  Retrieve current send buffer size.
+        int rc = getsockopt (w, SOL_SOCKET, SO_SNDBUF, &old_sndbuf,
+            &sndbuf_size);
+        errno_assert (rc == 0);
+        new_sndbuf = old_sndbuf * 2;
+
+        //  Double the new send buffer size.
+        rc = setsockopt (w, SOL_SOCKET, SO_SNDBUF, &new_sndbuf, sndbuf_size);
+        errno_assert (rc == 0);
+
+        //  Verify that the OS actually honored the request.
+        rc = getsockopt (w, SOL_SOCKET, SO_SNDBUF, &new_sndbuf, &sndbuf_size);
+        errno_assert (rc == 0);
+        zmq_assert (new_sndbuf > old_sndbuf);
+
+        //  Retry the sending operation; at this point it must succeed.
+        do {
+            nbytes = ::send (w, &cmd_, sizeof (command_t), 0);
+        } while (nbytes == -1 && errno == EINTR);
+    }
+    errno_assert (nbytes != -1);
+
+    //  This should never happen as we've already checked that command size is
+    //  less than PIPE_BUF.
+    zmq_assert (nbytes == sizeof (command_t));
+}
+
+int zmq::mailbox_t::recv (command_t *cmd_, bool block_)
+{
+#ifdef MSG_DONTWAIT
+
+    //  Attempt to read an entire command. Returns EAGAIN if non-blocking
+    //  mode is requested and a command is not available.
+    ssize_t nbytes = ::recv (r, cmd_, sizeof (command_t),
+        block_ ? 0 : MSG_DONTWAIT);
+    if (nbytes == -1 && (errno == EAGAIN || errno == EINTR))
+        return -1;
+#else
+
+    //  If required, set the reader to blocking mode.
+    if (block_) {
+        int flags = fcntl (r, F_GETFL, 0);
+        errno_assert (flags >= 0);
+        int rc = fcntl (r, F_SETFL, flags & ~O_NONBLOCK);
+        errno_assert (rc == 0);
+    }
+
+    //  Attempt to read an entire command. Returns EAGAIN if non-blocking
+    //  and a command is not available. Save value of errno if we wish to pass
+    //  it to caller.
+    int err = 0;
+    ssize_t nbytes = ::recv (r, cmd_, sizeof (command_t), 0);
+    if (nbytes == -1 && (errno == EAGAIN || errno == EINTR))  
+        err = errno;
+
+    //  Re-set the reader to non-blocking mode.
+    if (block_) {
+        int flags = fcntl (r, F_GETFL, 0);
+        errno_assert (flags >= 0);
+        int rc = fcntl (r, F_SETFL, flags | O_NONBLOCK);
+        errno_assert (rc == 0);
+    }
+
+    //  If the recv failed, return with the saved errno if set.
+    if (err != 0) {
+        errno = err;
+        return -1;
+    }
+
+#endif
+
+    //  Sanity check for success.
+    errno_assert (nbytes != -1);
+
+    //  Check whether we haven't got half of command.
+    zmq_assert (nbytes == sizeof (command_t));
+
+    return 0;
+}
+
+#endif
+
+int zmq::mailbox_t::make_socketpair (fd_t *r_, fd_t *w_)
+{
+#if defined ZMQ_HAVE_WINDOWS
+
+    //  Windows has no 'socketpair' function. CreatePipe is no good as pipe
+    //  handles cannot be polled on. Here we create the socketpair by hand.
+    *w_ = INVALID_SOCKET;
+    *r_ = INVALID_SOCKET;
+
+    //  Create listening socket.
+    SOCKET listener;
+    listener = socket (AF_INET, SOCK_STREAM, 0);
+    wsa_assert (listener != INVALID_SOCKET);
+
+    //  Set SO_REUSEADDR and TCP_NODELAY on listening socket.
+    BOOL so_reuseaddr = 1;
+    int rc = setsockopt (listener, SOL_SOCKET, SO_REUSEADDR,
+        (char *)&so_reuseaddr, sizeof (so_reuseaddr));
+    wsa_assert (rc != SOCKET_ERROR);
+    BOOL tcp_nodelay = 1;
+    rc = setsockopt (listener, IPPROTO_TCP, TCP_NODELAY,
+        (char *)&tcp_nodelay, sizeof (tcp_nodelay));
+    wsa_assert (rc != SOCKET_ERROR);
+
+    //  Bind listening socket to any free local port.
+    struct sockaddr_in addr;
+    memset (&addr, 0, sizeof (addr));
+    addr.sin_family = AF_INET;
+    addr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
+    addr.sin_port = 0;
+    rc = bind (listener, (const struct sockaddr*) &addr, sizeof (addr));
+    wsa_assert (rc != SOCKET_ERROR);
+
+    //  Retrieve local port listener is bound to (into addr).
+    int addrlen = sizeof (addr);
+    rc = getsockname (listener, (struct sockaddr*) &addr, &addrlen);
+    wsa_assert (rc != SOCKET_ERROR);
+
+    //  Listen for incomming connections.
+    rc = listen (listener, 1);
+    wsa_assert (rc != SOCKET_ERROR);
+
+    //  Create the writer socket.
+    *w_ = WSASocket (AF_INET, SOCK_STREAM, 0, NULL, 0,  0);
+    wsa_assert (*w_ != INVALID_SOCKET);
+
+    //  Set TCP_NODELAY on writer socket.
+    rc = setsockopt (*w_, IPPROTO_TCP, TCP_NODELAY,
+        (char *)&tcp_nodelay, sizeof (tcp_nodelay));
+    wsa_assert (rc != SOCKET_ERROR);
+
+    //  Connect writer to the listener.
+    rc = connect (*w_, (sockaddr *) &addr, sizeof (addr));
+    wsa_assert (rc != SOCKET_ERROR);
+
+    //  Accept connection from writer.
+    *r_ = accept (listener, NULL, NULL);
+    wsa_assert (*r_ != INVALID_SOCKET);
+
+    //  We don't need the listening socket anymore. Close it.
+    rc = closesocket (listener);
+    wsa_assert (rc != SOCKET_ERROR);
+
+    return 0;
+
+#elif defined ZMQ_HAVE_OPENVMS
+
+    //  Whilst OpenVMS supports socketpair - it maps to AF_INET only.  Further,
+    //  it does not set the socket options TCP_NODELAY and TCP_NODELACK which
+    //  can lead to performance problems.
+    //
+    //  The bug will be fixed in V5.6 ECO4 and beyond.  In the meantime, we'll
+    //  create the socket pair manually.
+    sockaddr_in lcladdr;
+    memset (&lcladdr, 0, sizeof (lcladdr));
+    lcladdr.sin_family = AF_INET;
+    lcladdr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
+    lcladdr.sin_port = 0;
+
+    int listener = socket (AF_INET, SOCK_STREAM, 0);
+    errno_assert (listener != -1);
+
+    int on = 1;
+    int rc = setsockopt (listener, IPPROTO_TCP, TCP_NODELAY, &on, sizeof (on));
+    errno_assert (rc != -1);
+
+    rc = setsockopt (listener, IPPROTO_TCP, TCP_NODELACK, &on, sizeof (on));
+    errno_assert (rc != -1);
+
+    rc = bind(listener, (struct sockaddr*) &lcladdr, sizeof (lcladdr));
+    errno_assert (rc != -1);
+
+    socklen_t lcladdr_len = sizeof (lcladdr);
+
+    rc = getsockname (listener, (struct sockaddr*) &lcladdr, &lcladdr_len);
+    errno_assert (rc != -1);
+
+    rc = listen (listener, 1);
+    errno_assert (rc != -1);
+
+    *w_ = socket (AF_INET, SOCK_STREAM, 0);
+    errno_assert (*w_ != -1);
+
+    rc = setsockopt (*w_, IPPROTO_TCP, TCP_NODELAY, &on, sizeof (on));
+    errno_assert (rc != -1);
+
+    rc = setsockopt (*w_, IPPROTO_TCP, TCP_NODELACK, &on, sizeof (on));
+    errno_assert (rc != -1);
+
+    rc = connect (*w_, (struct sockaddr*) &lcladdr, sizeof (lcladdr));
+    errno_assert (rc != -1);
+
+    *r_ = accept (listener, NULL, NULL);
+    errno_assert (*r_ != -1);
+
+    close (listener);
+
+    return 0;
+
+#else // All other implementations support socketpair()
+
+    int sv [2];
+    int rc = socketpair (AF_UNIX, SOCK_STREAM, 0, sv);
+    errno_assert (rc == 0);
+    *w_ = sv [0];
+    *r_ = sv [1];
+    return 0;
+
+#endif
+}
+