ZMQ-specific error codes added

bindings/c/zmq.h

@@ -35,6 +35,21 @@ extern "C" {
 #define ZMQ_EXPORT
 #endif
 
+////////////////////////////////////////////////////////////////////////////////
+//  0MQ errors.
+////////////////////////////////////////////////////////////////////////////////
+
+//  A number random anough not to collide with different errno ranges on
+//  different OSes. The assumption is that error_t is at least 32-bit type.
+#define ZMQ_HAUSNUMERO 156384712
+
+#define EMTHREAD (ZMQ_HAUSNUMERO + 1)
+#define EFSM (ZMQ_HAUSNUMERO + 2)
+#define ENOCOMPATPROTO (ZMQ_HAUSNUMERO + 3)
+
+//  Resolves system errors and 0MQ errors to human-readable string.
+ZMQ_EXPORT const char *zmq_strerror (int errnum);
+
 ////////////////////////////////////////////////////////////////////////////////
 //  0MQ message definition.
 ////////////////////////////////////////////////////////////////////////////////
@@ -154,8 +169,8 @@ ZMQ_EXPORT int zmq_term (void *context);
 //  Open a socket. 'type' is one of the socket types defined above.
 //
 //  Errors: EINVAL - invalid socket type.
-//          EMFILE - the number of application threads entitled to hold open
-//                   sockets at the same time was exceeded.
+//          EMTHREAD - the number of application threads entitled to hold open
+//                     sockets at the same time was exceeded.
 ZMQ_EXPORT void *zmq_socket (void *context, int type);
 
 //  Destroying the socket.
@@ -276,9 +291,15 @@ ZMQ_EXPORT int zmq_setsockopt (void *s, int option, const void *optval,
 //              "udp://192.168.0.111;224.1.1.1:5555".
 
 //  Bind the socket to a particular address.
+//
+//  Errors: EPROTONOSUPPORT - unsupported protocol.
+//          ENOCOMPATPROTO - protocol is not compatible with the socket type.
 ZMQ_EXPORT int zmq_bind (void *s, const char *addr);
 
 //  Connect the socket to a particular address.
+//
+//  Errors: EPROTONOSUPPORT - unsupported protocol.
+//          ENOCOMPATPROTO - protocol is not compatible with the socket type.
 ZMQ_EXPORT int zmq_connect (void *s, const char *addr);
 
 //  Sending and receiving messages.
@@ -303,12 +324,14 @@ ZMQ_EXPORT int zmq_connect (void *s, const char *addr);
 //
 //  Errors: EAGAIN - message cannot be sent at the moment (applies only to
 //                   non-blocking send).
-//          EFAULT - function isn't supported by particular socket type.
+//          ENOTSUP - function isn't supported by particular socket type.
+//          EFSM - function cannot be called at the moment. 
 ZMQ_EXPORT int zmq_send (void *s, struct zmq_msg_t *msg, int flags);
 
 //  Flush the messages that were send using ZMQ_NOFLUSH flag down the stream.
 //
-//  Errors: FAULT - function isn't supported by particular socket type.
+//  Errors: ENOTSUP - function isn't supported by particular socket type.
+//          EFSM - function cannot be called at the moment. 
 ZMQ_EXPORT int zmq_flush (void *s);
 
 //  Send a message from the socket 's'. 'flags' argument can be combination
@@ -316,7 +339,8 @@ ZMQ_EXPORT int zmq_flush (void *s);
 //
 //  Errors: EAGAIN - message cannot be received at the moment (applies only to
 //                   non-blocking receive).
-//          EFAULT - function isn't supported by particular socket type.
+//          ENOTSUP - function isn't supported by particular socket type.
+//          EFSM - function cannot be called at the moment. 
 ZMQ_EXPORT int zmq_recv (void *s, struct zmq_msg_t *msg, int flags);
 
 ////////////////////////////////////////////////////////////////////////////////

src/dispatcher.cpp

@@ -163,7 +163,7 @@ zmq::app_thread_t *zmq::dispatcher_t::choose_app_thread ()
             return app_threads [i];
 
     //  Thread limit was exceeded.
-    errno = EMFILE;
+    errno = EMTHREAD;
     return NULL;
 }
 

src/err.cpp

@@ -24,11 +24,16 @@
 
 const char *zmq::wsa_error()
 {
+
+
     int errcode = WSAGetLastError ();
     //  TODO: This is not a generic way to handle this...
     if (errcode == WSAEWOULDBLOCK)
         return NULL;
 
+    //  TODO:  It seems that list of Windows socket errors is longer than this.
+    //         Investigate whether there's a way to convert it into the string
+    //         automatically (wsaError->HRESULT->string?).
     return
         (errcode == WSABASEERR) ?
             "No Error" : 

src/pub.cpp

@@ -152,7 +152,7 @@ int zmq::pub_t::xflush ()
 
 int zmq::pub_t::xrecv (struct zmq_msg_t *msg_, int flags_)
 {
-    errno = EFAULT;
+    errno = ENOTSUP;
     return -1;
 }
 

src/rep.cpp

@@ -137,7 +137,7 @@ int zmq::rep_t::xsetsockopt (int option_, const void *optval_,
 int zmq::rep_t::xsend (struct zmq_msg_t *msg_, int flags_)
 {
     if (!waiting_for_reply) {
-        errno = EFAULT;
+        errno = EFSM;
         return -1;
     }
 
@@ -161,7 +161,7 @@ int zmq::rep_t::xsend (struct zmq_msg_t *msg_, int flags_)
 
 int zmq::rep_t::xflush ()
 {
-    errno = EFAULT;
+    errno = ENOTSUP;
     return -1;
 }
 
@@ -171,7 +171,7 @@ int zmq::rep_t::xrecv (struct zmq_msg_t *msg_, int flags_)
     zmq_msg_close (msg_);
 
     if (waiting_for_reply) {
-        errno = EFAULT;
+        errno = EFSM;
         return -1;
     }
 

src/req.cpp

@@ -120,12 +120,12 @@ int zmq::req_t::xsend (struct zmq_msg_t *msg_, int flags_)
     //  If we've sent a request and we still haven't got the reply,
     //  we can't send another request.
     if (waiting_for_reply) {
-        errno = EFAULT;
+        errno = EFSM;
         return -1;
     }
 
     if (out_pipes.empty ()) {
-        errno = EFAULT;
+        errno = EAGAIN;
         return -1;
     }
 
@@ -166,7 +166,7 @@ int zmq::req_t::xsend (struct zmq_msg_t *msg_, int flags_)
 
 int zmq::req_t::xflush ()
 {
-    errno = EFAULT;
+    errno = ENOTSUP;
     return -1;
 }
 
@@ -178,7 +178,7 @@ int zmq::req_t::xrecv (struct zmq_msg_t *msg_, int flags_)
     //  If request wasn't send, we can't wait for reply.
     if (!waiting_for_reply) {
         zmq_msg_init (msg_);
-        errno = EFAULT;
+        errno = EFSM;
         return -1;
     }
 

src/socket_base.cpp

@@ -100,8 +100,8 @@ int zmq::socket_base_t::bind (const char *addr_)
     }
 #endif
 
-    //  Unknown address type.
-    errno = EFAULT;
+    //  Unknown protocol.
+    errno = EPROTONOSUPPORT;
     return -1;
 }
 
@@ -185,7 +185,7 @@ int zmq::socket_base_t::connect (const char *addr_)
         //  If the socket type requires bi-directional communication
         //  multicast is not an option (it is uni-directional).
         if (options.requires_in && options.requires_out) {
-            errno = EFAULT;
+            errno = ENOCOMPATPROTO;
             return -1;
         }
 
@@ -235,8 +235,8 @@ int zmq::socket_base_t::connect (const char *addr_)
     }
 #endif
 
-    //  Unknown address type.
-    errno = EFAULT;
+    //  Unknown protoco.
+    errno = EPROTONOSUPPORT;
     return -1;
 }
 

src/sub.cpp

@@ -124,13 +124,13 @@ int zmq::sub_t::xsetsockopt (int option_, const void *optval_,
 
 int zmq::sub_t::xsend (struct zmq_msg_t *msg_, int flags_)
 {
-    errno = EFAULT;
+    errno = ENOTSUP;
     return -1;
 }
 
 int zmq::sub_t::xflush ()
 {
-    errno = EFAULT;
+    errno = ENOTSUP;
     return -1;
 }
 

src/zmq.cpp

@@ -19,6 +19,7 @@
 
 #include "../bindings/c/zmq.h"
 
+#include <string.h>
 #include <errno.h>
 #include <stdlib.h>
 #include <new>
@@ -35,6 +36,20 @@
 #include <sys/time.h>
 #endif
 
+const char *zmq_strerror (int errnum_)
+{
+    switch (errnum_) {
+    case EMTHREAD:
+        return "Number of preallocated application threads exceeded";
+    case EFSM:
+        return "Operation cannot be accomplished in current state";
+    case ENOCOMPATPROTO:
+        return "The protocol is not compatible with the socket type";
+    default:
+        return strerror (errnum_);
+    }
+}
+
 int zmq_msg_init (zmq_msg_t *msg_)
 {
     msg_->content = (zmq::msg_content_t*) ZMQ_VSM;