Merge pull request #1097 from hintjens/master

Added capabilities API

.gitignore

@@ -94,6 +94,7 @@ tests/test_proxy_chain
 tests/test_bind_src_address
 tests/test_metadata
 tests/test_id2fd
+tests/test_capabilities
 tests/test*.log
 tests/test*.trs
 src/platform.hpp*

doc/Makefile.am

@@ -10,7 +10,7 @@ MAN3 = zmq_bind.3 zmq_unbind.3 zmq_connect.3 zmq_disconnect.3 zmq_close.3 \
     zmq_errno.3 zmq_strerror.3 zmq_version.3 \
     zmq_sendmsg.3 zmq_recvmsg.3 \
     zmq_proxy.3 zmq_proxy_steerable.3 \
-    zmq_z85_encode.3 zmq_z85_decode.3 zmq_curve_keypair.3
+    zmq_z85_encode.3 zmq_z85_decode.3 zmq_curve_keypair.3 zmq_has.3
 
 MAN7 = zmq.7 zmq_tcp.7 zmq_pgm.7 zmq_epgm.7 zmq_inproc.7 zmq_ipc.7 \
     zmq_null.7 zmq_plain.7 zmq_curve.7 zmq_tipc.7

doc/zmq_has.txt

+zmq_has(3)
+==========
+
+
+NAME
+----
+zmq_has - check a ZMQ capability
+
+
+SYNOPSIS
+--------
+*int zmq_has (const char *capability);*
+
+
+DESCRIPTION
+-----------
+The _zmq_has()_ function shall report whether a specified capability is
+available in the library. This allows bindings and applications to probe
+a library directly, for transport and security options.
+
+Capabilities shall be lowercase strings. The following capabilities are
+defined:
+
+* ipc - the library supports the ipc:// protocol
+* pgm - the library supports the pgm:// protocol
+* tipc - the library supports the tipc:// protocol
+* norm - the library supports the norm:// protocol
+* curve - the library supports the CURVE security mechanism
+* gssapi - the library supports the GSSAPI security mechanism
+
+When this method is provided, the zmq.h header file will define
+ZMQ_HAS_CAPABILITIES.
+
+RETURN VALUE
+------------
+The _zmq_has()_ function shall return 1 if the specified capability is
+provided. Otherwise it shall return 0.
+
+
+AUTHORS
+-------
+This page was written by the 0MQ community. To make a change please
+read the 0MQ Contribution Policy at <http://www.zeromq.org/docs:contributing>.

include/zmq.h

@@ -359,9 +359,6 @@ ZMQ_EXPORT int zmq_send_const (void *s, const void *buf, size_t len, int flags);
 ZMQ_EXPORT int zmq_recv (void *s, void *buf, size_t len, int flags);
 ZMQ_EXPORT int zmq_socket_monitor (void *s, const char *addr, int events);
 
-ZMQ_EXPORT int zmq_sendmsg (void *s, zmq_msg_t *msg, int flags);
-ZMQ_EXPORT int zmq_recvmsg (void *s, zmq_msg_t *msg, int flags);
-
 /*  Experimental                                                              */
 struct iovec;
 
@@ -397,12 +394,21 @@ ZMQ_EXPORT int zmq_poll (zmq_pollitem_t *items, int nitems, long timeout);
 ZMQ_EXPORT int zmq_proxy (void *frontend, void *backend, void *capture);
 ZMQ_EXPORT int zmq_proxy_steerable (void *frontend, void *backend, void *capture, void *control);
 
+/*  Probe library capabilities  */
+
+#define ZMQ_HAS_CAPABILITIES 1
+ZMQ_EXPORT int zmq_has (const char *capability);
+
 /*  Deprecated aliases */
 #define ZMQ_STREAMER 1
 #define ZMQ_FORWARDER 2
 #define ZMQ_QUEUE 3
-/*  Deprecated method */
+
+/*  Deprecated methods */
 ZMQ_EXPORT int zmq_device (int type, void *frontend, void *backend);
+ZMQ_EXPORT int zmq_sendmsg (void *s, zmq_msg_t *msg, int flags);
+ZMQ_EXPORT int zmq_recvmsg (void *s, zmq_msg_t *msg, int flags);
+
 
 #undef ZMQ_EXPORT
 

include/zmq_utils.h

@@ -61,16 +61,16 @@ extern "C" {
 #   endif
 #endif
 
-/* These functions are documented by man pages                                */
+/*  These functions are documented by man pages                               */
 
-/* Encode data with Z85 encoding. Returns encoded data                        */
+/*  Encode data with Z85 encoding. Returns encoded data                       */
 ZMQ_EXPORT char *zmq_z85_encode (char *dest, uint8_t *data, size_t size);
 
-/* Decode data with Z85 encoding. Returns decoded data                        */
+/*  Decode data with Z85 encoding. Returns decoded data                       */
 ZMQ_EXPORT uint8_t *zmq_z85_decode (uint8_t *dest, char *string);
 
-/* Generate z85-encoded public and private keypair with libsodium.            */
-/* Returns 0 on success.                                                      */
+/*  Generate z85-encoded public and private keypair with libsodium.           */
+/*  Returns 0 on success.                                                     */
 ZMQ_EXPORT int zmq_curve_keypair (char *z85_public_key, char *z85_secret_key);
 
 typedef void (zmq_thread_fn) (void*);

src/options.cpp

@@ -68,6 +68,7 @@ int zmq::options_t::setsockopt (int option_, const void *optval_,
 #if defined (ZMQ_ACT_MILITANT)
     bool malformed = true;          //  Did caller pass a bad option value?
 #endif
+
     switch (option_) {
         case ZMQ_SNDHWM:
             if (is_int && value >= 0) {
@@ -415,7 +416,9 @@ int zmq::options_t::setsockopt (int option_, const void *optval_,
                 return 0;
             }
             break;
-	
+
+        //  If libgssapi isn't installed, these options provoke EINVAL
+#       ifdef HAVE_LIBGSSAPI_KRB5
         case ZMQ_GSSAPI_SERVER:
             if (is_int && (value == 0 || value == 1)) {
                 as_server = value;
@@ -423,7 +426,7 @@ int zmq::options_t::setsockopt (int option_, const void *optval_,
                 return 0;
             }
             break;
-		
+
         case ZMQ_GSSAPI_PRINCIPAL:
             if (optvallen_ > 0 && optvallen_ < 256 && optval_ != NULL) {
                 gss_principal.assign ((const char *) optval_, optvallen_);
@@ -447,7 +450,8 @@ int zmq::options_t::setsockopt (int option_, const void *optval_,
                 return 0;
             }
             break;
-	
+#       endif
+
         case ZMQ_HANDSHAKE_IVL:
             if (is_int && value >= 0) {
                 handshake_ivl = value;
@@ -480,6 +484,9 @@ int zmq::options_t::getsockopt (int option_, void *optval_, size_t *optvallen_)
 {
     bool is_int = (*optvallen_ == sizeof (int));
     int *value = (int *) optval_;
+#if defined (ZMQ_ACT_MILITANT)
+    bool malformed = true;          //  Did caller pass a bad option value?
+#endif
 
     switch (option_) {
         case ZMQ_SNDHWM:
@@ -758,6 +765,8 @@ int zmq::options_t::getsockopt (int option_, void *optval_, size_t *optvallen_)
             }
             break;
  
+        //  If libgssapi isn't installed, these options provoke EINVAL
+#       ifdef HAVE_LIBGSSAPI_KRB5
         case ZMQ_GSSAPI_SERVER:
             if (is_int) {
                 *value = as_server && mechanism == ZMQ_GSSAPI;
@@ -787,14 +796,25 @@ int zmq::options_t::getsockopt (int option_, void *optval_, size_t *optvallen_)
                 return 0;
             }
             break;
- 
+#endif
+
         case ZMQ_HANDSHAKE_IVL:
             if (is_int) {
                 *value = handshake_ivl;
                 return 0;
             }
             break;
+            
+        default:
+#if defined (ZMQ_ACT_MILITANT)
+            malformed = false;
+#endif
+            break;
     }
+#if defined (ZMQ_ACT_MILITANT)
+    if (malformed)
+        zmq_assert (false);
+#endif
     errno = EINVAL;
     return -1;
 }

src/zmq.cpp

@@ -1043,3 +1043,35 @@ int zmq_device (int /* type */, void *frontend_, void *backend_)
         (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;
+}

tests/Makefile.am

@@ -48,9 +48,10 @@ noinst_PROGRAMS = test_system \
                   test_ipc_wildcard \
                   test_diffserv \
                   test_connect_rid \
-		  test_bind_src_address \
-		  test_metadata\
-		  test_id2fd
+                  test_bind_src_address \
+                  test_metadata \
+                  test_id2fd \
+                  test_capabilities
 
 if !ON_MINGW
 noinst_PROGRAMS += test_shutdown_stress \
@@ -127,6 +128,7 @@ test_connect_rid_SOURCES = test_connect_rid.cpp
 test_bind_src_address_SOURCES = test_bind_src_address.cpp
 test_metadata_SOURCES = test_metadata.cpp
 test_id2fd_SOURCES = test_id2fd.cpp
+test_capabilities_SOURCES = test_capabilities.cpp
 if !ON_MINGW
 test_shutdown_stress_SOURCES = test_shutdown_stress.cpp
 test_pair_ipc_SOURCES = test_pair_ipc.cpp testutil.hpp

tests/test_capabilities.cpp

+/*
+    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/>.
+*/
+
+#include "testutil.hpp"
+
+int main (void)
+{
+#if !defined (ZMQ_HAVE_WINDOWS) && !defined (ZMQ_HAVE_OPENVMS)
+    assert (zmq_has ("ipc"));
+#else
+    assert (!zmq_has ("ipc"));
+#endif
+
+#if defined (ZMQ_HAVE_OPENPGM)
+    assert (zmq_has ("pgm"));
+#else
+    assert (!zmq_has ("pgm"));
+#endif
+    
+#if defined (ZMQ_HAVE_TIPC)
+    assert (zmq_has ("tipc"));
+#else
+    assert (!zmq_has ("tipc"));
+#endif
+    
+#if defined (ZMQ_HAVE_NORM)
+    assert (zmq_has ("norm"));
+#else
+    assert (!zmq_has ("norm"));
+#endif
+    
+#if defined (HAVE_LIBSODIUM)
+    assert (zmq_has ("curve"));
+#else
+    assert (!zmq_has ("curve"));
+#endif
+    
+#if defined (HAVE_LIBGSSAPI_KRB5)
+    assert (zmq_has ("gssapi"));
+#else
+    assert (!zmq_has ("gssapi"));
+#endif
+
+    return 0;
+}