Free pointers before throwing a ZeroMQException

CHANGELOG.md

@@ -1,3 +1,13 @@
+## 1.0.0-dev.6
+
+### Free pointers before throwing a ZeroMQException
+- Free pointers before throwing a ZeroMQException
+- Add return code to `zmq_setsockopt` function
+- Add return code check to `ZSocket.setOption` function
+- Add `zmq_has` function for checking supported capabilities
+- Add helper functions for `zmq_has`
+
+
 ## 1.0.0-dev.5
 
 ### Fix destroying poller and loading shared library

lib/src/bindings.dart

@@ -32,6 +32,9 @@ class ZMQPollItem extends Struct {
   external int revents;
 }
 
+typedef ZmqHasNative = Int32 Function(Pointer<Utf8> capability);
+typedef ZmqHasDart = int Function(Pointer<Utf8> capability);
+
 typedef ZmqBindNative = Int32 Function(
     ZMQSocket socket, Pointer<Utf8> endpoint);
 typedef ZmqBindDart = int Function(ZMQSocket socket, Pointer<Utf8> endpoint);
@@ -107,14 +110,16 @@ typedef ZmqSendNative = Int32 Function(
 typedef ZmqSendDart = int Function(
     ZMQSocket socket, Pointer<Void> buffer, int size, int flags);
 
-typedef ZmqsetsockoptNative = Void Function(
+typedef ZmqsetsockoptNative = Int32 Function(
     ZMQSocket socket, Int32 option, Pointer<Uint8> optval, IntPtr optvallen);
-typedef ZmqSetsockoptDart = void Function(
+typedef ZmqSetsockoptDart = int Function(
     ZMQSocket socket, int option, Pointer<Uint8> optval, int optvallen);
 
 class ZMQBindings {
   final DynamicLibrary library;
 
+  late final ZmqHasDart zmq_has;
+
   late final ZmqErrnoDart zmq_errno;
 
   late final ZmqBindDart zmq_bind;
@@ -143,6 +148,7 @@ class ZMQBindings {
   late final ZmqSetsockoptDart zmq_setsockopt;
 
   ZMQBindings(this.library) {
+    zmq_has = library.lookupFunction<ZmqHasNative, ZmqHasDart>('zmq_has');
     zmq_errno =
         library.lookupFunction<ZmqErrnoNative, ZmqErrnoDart>('zmq_errno');
     zmq_bind = library.lookupFunction<ZmqBindNative, ZmqBindDart>('zmq_bind');

lib/src/zeromq.dart

@@ -70,7 +70,9 @@ class ZContext {
   }
 
   void _initBindings() {
-    final loaded = _loadBinding('zmq') || _loadBinding('libzmq-v142-mt-4_3_5');
+    final loaded = _loadBinding('zmq') ||
+        _loadBinding('libzmq') ||
+        _loadBinding('libzmq-v142-mt-4_3_5');
     if (!loaded) {
       throw Exception('Could not load any zeromq library');
     }
@@ -169,6 +171,79 @@ class ZContext {
     _stopCompleter?.complete(null);
   }
 
+  /// Check 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
+  /// * `draft` - the library is built with the draft api
+  ///
+  /// You can also use one of the direct functions [hasIPC], [hasPGM],
+  /// [hasTIPC], [hasNORM], [hasCURVE], [hasGSSAPI] and [hasDRAFT] instead.
+  ///
+  /// Returns true if supported, false if not
+  bool hasCapability(final String capability) {
+    final ptr = capability.toNativeUtf8();
+    final result = _bindings.zmq_has(ptr);
+    malloc.free(ptr);
+    return result == 1;
+  }
+
+  /// Check if the library supports the ipc:// protocol
+  ///
+  /// Returns true if supported, false if not
+  bool hasIPC() {
+    return hasCapability('ipc');
+  }
+
+  /// Check if the library supports the pgm:// protocol
+  ///
+  /// Returns true if supported, false if not
+  bool hasPGM() {
+    return hasCapability('pgm');
+  }
+
+  /// Check if the library supports the tipc:// protocol
+  ///
+  /// Returns true if supported, false if not
+  bool hasTIPC() {
+    return hasCapability('tipc');
+  }
+
+  /// Check if the library supports the norm:// protocol
+  ///
+  /// Returns true if supported, false if not
+  bool hasNORM() {
+    return hasCapability('norm');
+  }
+
+  /// Check if the library supports the CURVE security mechanism
+  ///
+  /// Returns true if supported, false if not
+  bool hasCURVE() {
+    return hasCapability('curve');
+  }
+
+  /// Check if the library supports the GSSAPI security mechanism
+  ///
+  /// Returns true if supported, false if not
+  bool hasGSSAPI() {
+    return hasCapability('gssapi');
+  }
+
+  /// Check if the library is built with the draft api
+  ///
+  /// Returns true if supported, false if not
+  bool hasDRAFT() {
+    return hasCapability('draft');
+  }
+
   /// Create a new socket of the given [mode]
   ZSocket createSocket(SocketType mode) {
     final socket = _bindings.zmq_socket(_context, mode.index);
@@ -476,8 +551,8 @@ class ZSocket {
     final sendParams = more ? ZMQ_SNDMORE : 0;
     final result = _context._bindings
         .zmq_send(_socket, ptr.cast(), data.length, sendParams);
-    _context._checkReturnCode(result);
     malloc.free(ptr);
+    _context._checkReturnCode(result);
   }
 
   /// Sends the given [frame] over this socket
@@ -508,8 +583,8 @@ class ZSocket {
     _checkNotClosed();
     final endpointPointer = address.toNativeUtf8();
     final result = _context._bindings.zmq_bind(_socket, endpointPointer);
-    _context._checkReturnCode(result);
     malloc.free(endpointPointer);
+    _context._checkReturnCode(result);
   }
 
   /// Connects the socket to an endpoint and then accepts incoming connections on that endpoint.
@@ -521,8 +596,8 @@ class ZSocket {
     _checkNotClosed();
     final endpointPointer = address.toNativeUtf8();
     final result = _context._bindings.zmq_connect(_socket, endpointPointer);
-    _context._checkReturnCode(result);
     malloc.free(endpointPointer);
+    _context._checkReturnCode(result);
   }
 
   /// Closes the socket and releases underlying resources.
@@ -539,9 +614,10 @@ class ZSocket {
   /// Set a socket [option] to a specific [value]
   void setOption(final int option, final String value) {
     final ptr = value.toNativeUtf8();
-    _context._bindings
+    final result = _context._bindings
         .zmq_setsockopt(_socket, option, ptr.cast<Uint8>(), ptr.length);
     malloc.free(ptr);
+    _context._checkReturnCode(result);
   }
 
   /// Sets the socket's long term secret key.
@@ -614,13 +690,13 @@ class ZeroMQException implements Exception {
   /// Maps error codes to messages
   static const Map<int, String> _errorMessages = {
     // errno
-    EINTR: 'The operation was interrupted',
-    EBADF: 'Bad file descriptor',
-    // EAGAIN: '', // denpendant on what function has been called before
-    EACCES: 'Permission denied',
-    // EFAULT: '', // denpendant on what function has been called before
-    // EINVAL: '', // denpendant on what function has been called before
-    // EMFILE: '', // denpendant on what function has been called before
+    EINTR: 'EINTR: The operation was interrupted',
+    EBADF: 'EBADF: Bad file descriptor',
+    EAGAIN: 'EAGAIN', // denpendant on what function has been called before
+    EACCES: 'EACCES: Permission denied',
+    EFAULT: 'EFAULT', // denpendant on what function has been called before
+    EINVAL: 'EINVAL', // denpendant on what function has been called before
+    EMFILE: 'EMFILE', // denpendant on what function has been called before
 
     // 0MQ errors
     ENOTSUP: 'Not supported',

pubspec.yaml

@@ -1,6 +1,6 @@
 name: dartzmq
 description: A simple dart zeromq implementation/wrapper around the libzmq C++ library
-version: 1.0.0-dev.5
+version: 1.0.0-dev.6
 homepage: https://github.com/enwi/dartzmq
 
 environment: