EINTR returned from the blocking functions

doc/zmq_getsockopt.txt

@@ -216,6 +216,8 @@ option value.
 The 0MQ 'context' associated with the specified 'socket' was terminated.
 *EFAULT*::
 The provided 'socket' was not valid (NULL).
+*EINTR*::
+The operation was interrupted by delivery of a signal.
 
 
 EXAMPLE

doc/zmq_poll.txt

@@ -98,6 +98,8 @@ At least one of the members of the 'items' array refers to a 'socket' whose
 associated 0MQ 'context' was terminated.
 *EFAULT*::
 The provided 'items' was not valid (NULL).
+*EINTR*::
+The poll was interrupted by delivery of a signal before any event was available.
 
 
 EXAMPLE

doc/zmq_recv.txt

@@ -65,6 +65,9 @@ _messaging patterns_ section of linkzmq:zmq_socket[3] for more information.
 The 0MQ 'context' associated with the specified 'socket' was terminated.
 *EFAULT*::
 The provided 'socket' was not valid (NULL).
+*EINTR*::
+The operation was interrupted by delivery of a signal before a message was
+available.
 
 
 EXAMPLE

doc/zmq_send.txt

@@ -71,6 +71,9 @@ _messaging patterns_ section of linkzmq:zmq_socket[3] for more information.
 The 0MQ 'context' associated with the specified 'socket' was terminated.
 *EFAULT*::
 The provided 'context' was not valid (NULL).
+*EINTR*::
+The operation was interrupted by delivery of a signal before the message was
+sent.
 
 
 EXAMPLE

doc/zmq_setsockopt.txt

@@ -231,6 +231,8 @@ _option_value_ is invalid.
 The 0MQ 'context' associated with the specified 'socket' was terminated.
 *EFAULT*::
 The provided 'socket' was not valid (NULL).
+*EINTR*::
+The operation was interrupted by delivery of a signal.
 
 
 EXAMPLE

src/ctx.cpp

@@ -219,11 +219,6 @@ void zmq::ctx_t::send_command (uint32_t slot_, const command_t &command_)
     slots [slot_]->send (command_);
 }
 
-bool zmq::ctx_t::recv_command (uint32_t slot_, command_t *command_, bool block_)
-{
-    return slots [slot_]->recv (command_, block_);
-}
-
 zmq::io_thread_t *zmq::ctx_t::choose_io_thread (uint64_t affinity_)
 {
     //  Find the I/O thread with minimum load.

src/ctx.hpp

@@ -64,9 +64,6 @@ namespace zmq
         //  Send command to the destination slot.
         void send_command (uint32_t slot_, const command_t &command_);
 
-        //  Receive command from the source slot.
-        bool recv_command (uint32_t slot_, command_t *command_, bool block_);
-
         //  Returns the I/O thread that is the least busy at the moment.
         //  Taskset specifies which I/O threads are eligible (0 = all).
         class io_thread_t *choose_io_thread (uint64_t taskset_);

src/io_thread.cpp

@@ -71,8 +71,12 @@ void zmq::io_thread_t::in_event ()
 
         //  Get the next command. If there is none, exit.
         command_t cmd;
-        if (!signaler.recv (&cmd, false))
+        int rc = signaler.recv (&cmd, false);
+        if (rc != 0 && errno == EINTR)
+            continue;
+        if (rc != 0 && errno == EAGAIN)
              break;
+        errno_assert (rc == 0);
 
         //  Process the command.
         cmd.destination->process_command (cmd);

src/signaler.cpp

@@ -112,7 +112,7 @@ void zmq::signaler_t::send (const command_t &cmd_)
     zmq_assert (rc == sizeof (command_t));
 }
 
-bool zmq::signaler_t::recv (command_t *cmd_, bool block_)
+int zmq::signaler_t::recv (command_t *cmd_, bool block_)
 {
     if (block_) {
 
@@ -122,10 +122,12 @@ bool zmq::signaler_t::recv (command_t *cmd_, bool block_)
         wsa_assert (rc != SOCKET_ERROR);
     }
 
-    bool result;
+    int err;
+    int result;
     int nbytes = ::recv (r, (char*) cmd_, sizeof (command_t), 0);
     if (nbytes == -1 && WSAGetLastError () == WSAEWOULDBLOCK) {
-        result = false;
+        err = EAGAIN;
+        result = -1;
     }
     else {
         wsa_assert (nbytes != -1);
@@ -133,7 +135,7 @@ bool zmq::signaler_t::recv (command_t *cmd_, bool block_)
         //  Check whether we haven't got half of a signal.
         zmq_assert (nbytes % sizeof (uint32_t) == 0);
 
-        result = true;
+        result = 0;
     }
 
     if (block_) {
@@ -144,6 +146,8 @@ bool zmq::signaler_t::recv (command_t *cmd_, bool block_)
         wsa_assert (rc != SOCKET_ERROR);
     }
 
+    if (result == -1)
+        errno = err;
     return result;
 }
 
@@ -184,7 +188,7 @@ void zmq::signaler_t::send (const command_t &cmd_)
     zmq_assert (nbytes == sizeof (command_t));
 }
 
-bool zmq::signaler_t::recv (command_t *cmd_, bool block_)
+int zmq::signaler_t::recv (command_t *cmd_, bool block_)
 {
     if (block_) {
 
@@ -196,13 +200,12 @@ bool zmq::signaler_t::recv (command_t *cmd_, bool block_)
         errno_assert (rc != -1);
     }
 
-    bool result;
+    int err;
-    ssize_t nbytes;
+    int result;
-    do {
+    ssize_t nbytes = ::recv (r, (char*) cmd_, sizeof (command_t), 0);
-        nbytes = ::recv (r, (char*) cmd_, sizeof (command_t), 0);
+    if (nbytes == -1 && (errno == EAGAIN || errno == EINTR)) {
-    } while (nbytes == -1 && errno == EINTR);
+        err = errno;
-    if (nbytes == -1 && errno == EAGAIN) {
+        result = -1;
-        result = false;
     }
     else {
         zmq_assert (nbytes != -1);
@@ -210,7 +213,7 @@ bool zmq::signaler_t::recv (command_t *cmd_, bool block_)
         //  Check whether we haven't got half of command.
         zmq_assert (nbytes == sizeof (command_t));
 
-        result = true;
+        result = 0;
     }
 
    if (block_) {
@@ -223,6 +226,8 @@ bool zmq::signaler_t::recv (command_t *cmd_, bool block_)
         errno_assert (rc != -1);
     }
 
+    if (result == -1)
+        errno = err;
     return result;
 }
 
@@ -266,24 +271,18 @@ void zmq::signaler_t::send (const command_t &cmd_)
     zmq_assert (nbytes == sizeof (command_t));
 }
 
-bool zmq::signaler_t::recv (command_t *cmd_, bool block_)
+int zmq::signaler_t::recv (command_t *cmd_, bool block_)
 {
     ssize_t nbytes;
-    do {
+    nbytes = ::recv (r, cmd_, sizeof (command_t), block_ ? 0 : MSG_DONTWAIT);
-        nbytes = ::recv (r, cmd_, sizeof (command_t),
+    if (nbytes == -1 && (errno == EAGAIN || errno == EINTR))
-            block_ ? 0 : MSG_DONTWAIT);
+        return -1;
-    } while (nbytes == -1 && errno == EINTR);
-
-    //  If there's no signal available return false.
-    if (nbytes == -1 && errno == EAGAIN)
-        return false;
-
     errno_assert (nbytes != -1);
 
     //  Check whether we haven't got half of command.
     zmq_assert (nbytes == sizeof (command_t));
 
-    return true;
+    return 0;
 }
 
 #endif

src/signaler.hpp

@@ -40,7 +40,7 @@ namespace zmq
 
         fd_t get_fd ();
         void send (const command_t &cmd_);
-        bool recv (command_t *cmd_, bool block_);
+        int recv (command_t *cmd_, bool block_);
         
     private:
 

src/socket_base.cpp

@@ -244,7 +244,10 @@ int zmq::socket_base_t::getsockopt (int option_, void *optval_,
             errno = EINVAL;
             return -1;
         }
-        process_commands (false, false);
+        int rc = process_commands (false, false);
+        if (rc != 0 && errno == EINTR)
+            return -1;
+        errno_assert (rc == 0);
         *((uint32_t*) optval_) = 0;
         if (has_out ())
             *((uint32_t*) optval_) |= ZMQ_POLLOUT;
@@ -420,18 +423,16 @@ int zmq::socket_base_t::send (::zmq_msg_t *msg_, int flags_)
     }
 
     //  Process pending commands, if any.
-    process_commands (false, true);
+    int rc = process_commands (false, true);
-    if (unlikely (zombie)) {
+    if (unlikely (rc != 0))
-        errno = ETERM;
         return -1;
-    }
 
     //  At this point we impose the MORE flag on the message.
     if (flags_ & ZMQ_SNDMORE)
         msg_->flags |= ZMQ_MSG_MORE;
 
     //  Try to send the message.
-    int rc = xsend (msg_, flags_);
+    rc = xsend (msg_, flags_);
     if (rc == 0)
         return 0;
 
@@ -445,11 +446,8 @@ int zmq::socket_base_t::send (::zmq_msg_t *msg_, int flags_)
     while (rc != 0) {
         if (errno != EAGAIN)
             return -1;
-        process_commands (true, false);
+        if (unlikely (process_commands (true, false) != 0))
-        if (unlikely (zombie)) {
-            errno = ETERM;
             return -1;
-        }
         rc = xsend (msg_, flags_);
     }
     return 0;
@@ -475,11 +473,8 @@ int zmq::socket_base_t::recv (::zmq_msg_t *msg_, int flags_)
     //  described above) from the one used by 'send'. This is because counting
     //  ticks is more efficient than doing rdtsc all the time.
     if (++ticks == inbound_poll_rate) {
-        process_commands (false, false);
+        if (unlikely (process_commands (false, false) != 0))
-        if (unlikely (zombie)) {
-            errno = ETERM;
             return -1;
-        }
         ticks = 0;
     }
 
@@ -501,11 +496,8 @@ int zmq::socket_base_t::recv (::zmq_msg_t *msg_, int flags_)
     if (flags_ & ZMQ_NOBLOCK) {
         if (errno != EAGAIN)
             return -1;
-        process_commands (false, false);
+        if (unlikely (process_commands (false, false) != 0))
-        if (unlikely (zombie)) {
-            errno = ETERM;
             return -1;
-        }
         ticks = 0;
 
         rc = xrecv (msg_, flags_);
@@ -522,11 +514,8 @@ int zmq::socket_base_t::recv (::zmq_msg_t *msg_, int flags_)
     while (rc != 0) {
         if (errno != EAGAIN)
             return -1;
-        process_commands (true, false);
+        if (unlikely (process_commands (true, false) != 0))
-        if (unlikely (zombie)) {
-            errno = ETERM;
             return -1;
-        }
         rc = xrecv (msg_, flags_);
         ticks = 0;
     }
@@ -619,13 +608,15 @@ bool zmq::socket_base_t::dezombify ()
     return false;
 }
 
-void zmq::socket_base_t::process_commands (bool block_, bool throttle_)
+int zmq::socket_base_t::process_commands (bool block_, bool throttle_)
 {
-    bool received;
+    int rc;
     command_t cmd;
     if (block_) {
-        received = signaler.recv (&cmd, true);
+        rc = signaler.recv (&cmd, true);
-        zmq_assert (received);
+        if (rc == -1 && errno == EINTR)
+            return -1;
+        errno_assert (rc == 0);
     }
     else {
 
@@ -649,24 +640,40 @@ void zmq::socket_base_t::process_commands (bool block_, bool throttle_)
 #else
 #error
 #endif
-
             //  Check whether certain time have elapsed since last command
             //  processing.
-            if (current_time - last_processing_time <= max_command_delay)
+            if (current_time - last_processing_time <= max_command_delay) {
-                return;
+
+                //  No command was processed, so the socket should
+                //  not get into the zombie state.
+                zmq_assert (!zombie);
+                return 0;
+            }
             last_processing_time = current_time;
         }
 #endif
 
         //  Check whether there are any commands pending for this thread.
-        received = signaler.recv (&cmd, false);
+        rc = signaler.recv (&cmd, false);
     }
 
     //  Process all the commands available at the moment.
-    while (received) {
+    while (true) {
+        if (rc == -1 && errno == EAGAIN)
+            break;
+        if (rc == -1 && errno == EINTR)
+            return -1;
+        errno_assert (rc == 0);
         cmd.destination->process_command (cmd);
-        received = signaler.recv (&cmd, false);
+        rc = signaler.recv (&cmd, false);
      }
+
+    if (zombie) {
+        errno = ETERM;
+        return -1;
+    }
+
+    return 0;
 }
 
 void zmq::socket_base_t::process_stop ()

src/socket_base.hpp

@@ -124,7 +124,6 @@ namespace zmq
 
     private:
 
-//  TODO: Check whether we still need this flag...
         //  If true, socket was already closed but not yet deallocated
         //  because either shutdown is in process or there are still pipes
         //  attached to the socket.
@@ -147,7 +146,7 @@ namespace zmq
         //  set to true, returns only after at least one command was processed.
         //  If throttle argument is true, commands are processed at most once
         //  in a predefined time period.
-        void process_commands (bool block_, bool throttle_);
+        int process_commands (bool block_, bool throttle_);
 
         //  Handlers for incoming commands.
         void process_stop ();

src/zmq.cpp

@@ -409,17 +409,12 @@ int zmq_poll (zmq_pollitem_t *items_, int nitems_, long timeout_)
 
     while (true) {
 
-        //  Wait for events. Ignore interrupts if there's infinite timeout.
+        //  Wait for events.
         while (true) {
             int rc = poll (pollfds, nitems_, first_pass ? 0 : timeout);
             if (rc == -1 && errno == EINTR) {
-                if (timeout_ < 0)
-                    continue;
-                else {
-                    //  TODO: Calculate remaining timeout and restart poll ().
                 free (pollfds);
-                    return 0;
+                return -1;
-                }
             }
             errno_assert (rc >= 0);
             break;
@@ -474,6 +469,9 @@ int zmq_poll (zmq_pollitem_t *items_, int nitems_, long timeout_)
         if (timeout == -1 && nevents == 0)
             continue;
 
+        //  TODO: if nevents is zero recompute timeout and loop
+        //  if it is not yet reached.
+
         break;
     }
 
@@ -544,13 +542,8 @@ int zmq_poll (zmq_pollitem_t *items_, int nitems_, long timeout_)
 #if defined ZMQ_HAVE_WINDOWS
             wsa_assert (rc != SOCKET_ERROR);
 #else
-            if (rc == -1 && errno == EINTR) {
+            if (rc == -1 && errno == EINTR)
-                if (timeout_ < 0)
+                return -1;
-                    continue;
-                else
-                    //  TODO: Calculate remaining timeout and restart select ().
-                    return 0;
-            }
             errno_assert (rc >= 0);
 #endif
             break;
@@ -610,6 +603,9 @@ int zmq_poll (zmq_pollitem_t *items_, int nitems_, long timeout_)
         if (timeout_ < 0 && nevents == 0)
             continue;
 
+        //  TODO: if nevents is zero recompute timeout and loop
+        //  if it is not yet reached.
+
         break;
     }