Merge pull request zeromq#450 from gummif/gfa/build-examples

Problem: Examples are not compiled

CMakeLists.txt

@@ -101,4 +101,7 @@ option(CPPZMQ_BUILD_TESTS "Whether or not to build the tests" ON)
 if (CPPZMQ_BUILD_TESTS)
     enable_testing()
     add_subdirectory(tests)
+    if (CMAKE_CXX_STANDARD AND NOT CMAKE_CXX_STANDARD EQUAL 98 AND CMAKE_CXX_STANDARD GREATER_EQUAL 11)
+        add_subdirectory(examples)
+    endif()
 endif()

README.md

@@ -53,18 +53,22 @@ int main()
     sock.send(zmq::str_buffer("Hello, world"), zmq::send_flags::dontwait);
 }
 ```
-This a more complex example where we send and receive multi-part messages.
+This a more complex example where we send and receive multi-part messages over TCP with a wildcard port.
 ```c++
 #include <iostream>
 #include <zmq_addon.hpp>
 
 int main()
 {
     zmq::context_t ctx;
-    zmq::socket_t sock1(ctx, zmq::socket_type::pair);
-    zmq::socket_t sock2(ctx, zmq::socket_type::pair);
-    sock1.bind("inproc://test");
-    sock2.connect("inproc://test");
+    zmq::socket_t sock1(ctx, zmq::socket_type::push);
+    zmq::socket_t sock2(ctx, zmq::socket_type::pull);
+    sock1.bind("tcp://127.0.0.1:*");
+    const std::string last_endpoint =
+        sock1.get(zmq::sockopt::last_endpoint);
+    std::cout << "Connecting to "
+              << last_endpoint << std::endl;
+    sock2.connect(last_endpoint);
 
     std::array<zmq::const_buffer, 2> send_msgs = {
         zmq::str_buffer("foo"),
@@ -84,6 +88,8 @@ int main()
 }
 ```
 
+See the `examples` directory for more examples. When the project is compiled with tests enabled, each example gets compiled to an executable.
+
 Compatibility Guidelines
 ========================
 

examples/CMakeLists.txt

@@ -0,0 +1,39 @@
+cmake_minimum_required(VERSION 3.0 FATAL_ERROR)
+
+project(cppzmq-examples CXX)
+
+# place binaries and libraries according to GNU standards
+
+include(GNUInstallDirs)
+set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})
+set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})
+set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_BINDIR})
+
+find_package(Threads)
+
+add_executable(
+    pubsub_multithread_inproc
+    pubsub_multithread_inproc.cpp
+)
+target_link_libraries(
+    pubsub_multithread_inproc
+    PRIVATE cppzmq ${CMAKE_THREAD_LIBS_INIT}
+)
+
+add_executable(
+    hello_world
+    hello_world.cpp
+)
+target_link_libraries(
+    hello_world
+    PRIVATE cppzmq ${CMAKE_THREAD_LIBS_INIT}
+)
+
+add_executable(
+    multipart_messages
+    multipart_messages.cpp
+)
+target_link_libraries(
+    multipart_messages
+    PRIVATE cppzmq ${CMAKE_THREAD_LIBS_INIT}
+)

examples/hello_world.cpp

@@ -0,0 +1,9 @@
+#include <zmq.hpp>
+
+int main()
+{
+    zmq::context_t ctx;
+    zmq::socket_t sock(ctx, zmq::socket_type::push);
+    sock.bind("inproc://test");
+    sock.send(zmq::str_buffer("Hello, world"), zmq::send_flags::dontwait);
+}

examples/multipart_messages.cpp

@@ -0,0 +1,31 @@
+#include <iostream>
+#include <zmq_addon.hpp>
+
+int main()
+{
+    zmq::context_t ctx;
+    zmq::socket_t sock1(ctx, zmq::socket_type::push);
+    zmq::socket_t sock2(ctx, zmq::socket_type::pull);
+    sock1.bind("tcp://127.0.0.1:*");
+    const std::string last_endpoint =
+        sock1.get(zmq::sockopt::last_endpoint);
+    std::cout << "Connecting to "
+              << last_endpoint << std::endl;
+    sock2.connect(last_endpoint);
+
+    std::array<zmq::const_buffer, 2> send_msgs = {
+        zmq::str_buffer("foo"),
+        zmq::str_buffer("bar!")
+    };
+    if (!zmq::send_multipart(sock1, send_msgs))
+        return 1;
+
+    std::vector<zmq::message_t> recv_msgs;
+    const auto ret = zmq::recv_multipart(
+        sock2, std::back_inserter(recv_msgs));
+    if (!ret)
+        return 1;
+    std::cout << "Got " << *ret
+              << " messages" << std::endl;
+    return 0;
+}

examples/pubsub_multithread_inproc.cpp

@@ -40,9 +40,10 @@ void SubscriberThread1(zmq::context_t *ctx) {
         zmq::recv_result_t result =
           zmq::recv_multipart(subscriber, std::back_inserter(recv_msgs));
         assert(result && "recv failed");
+        assert(*result == 2);
 
-        std::cout << "Thread2: [" << recv_msgs[0].to_string_view() << "] "
-                  << recv_msgs[1].to_string_view() << std::endl;
+        std::cout << "Thread2: [" << recv_msgs[0].to_string() << "] "
+                  << recv_msgs[1].to_string() << std::endl;
     }
 }
 
@@ -60,9 +61,10 @@ void SubscriberThread2(zmq::context_t *ctx) {
         zmq::recv_result_t result =
           zmq::recv_multipart(subscriber, std::back_inserter(recv_msgs));
         assert(result && "recv failed");
+        assert(*result == 2);
 
-        std::cout << "Thread3: [" << recv_msgs[0].to_string_view() << "] "
-                  << recv_msgs[1].to_string_view() << std::endl;
+        std::cout << "Thread3: [" << recv_msgs[0].to_string() << "] "
+                  << recv_msgs[1].to_string() << std::endl;
     }
 }