paho.mqtt.cpp-1.5.3版本

# Eclipse Paho MQTT C++ Client Library This repository contains the source code for the [Eclipse Paho](http://eclipse.org/paho) MQTT C++ client library for memory-managed operating systems such as Linux, MacOS, and Windows. This code builds a library which enables Modern C++ applications (C++17 and beyond) to connect to an [MQTT](http://mqtt.org) broker, publish messages, subscribe to topics, and receive messages from the broker. The library has the following features: - Support for MQTT v3.1, v3.1.1, and v5. - Network Transports: - Standard TCP - UNIX-domain sockets - Secure sockets with SSL/TLS - WebSockets - Secure and insecure - Proxy support - Message persistence - User configurable - Built-in File persistence - User-defined key/value persistence easy to implement - Automatic Reconnect - Offline Buffering - High Availability - Blocking and non-blocking APIs - Modern C++ interface (C++17) This code requires the [Paho C library](https://github.com/eclipse/paho.mqtt.c) by Ian Craggs, et al., specifically version 1.3.14 or possibly later. ## Latest News To keep up with the latest announcements for this project, or to ask questions: **Email:** [Eclipse Paho Mailing List](https://accounts.eclipse.org/mailing-list/paho-dev) ### What's New in v1.5.x The latest updates for v1.5 moved the codebase to C++17 and added support for UNIX-domain sockets. They also fixed a number of build issues, now targeting the latest Paho C release, v1.3.14. The primary changes in the v1.5 versions are: - Updated the code base to C++17 - Support for the Paho C v1.3.14 release. - Support for UNIX-domain sockets - Reorganize and reformat the sources and added a .clang-format capability. - Create universal client instances that can connect using v3 or v5. (i.e. no more instances that are only v3 capable) - Bump the CMake to v3.13 - Fix a large number of CMake build issues - Updated the GitHub CI - (v1.5.3) Fixes for building this library and the Paho C library with the latest C & C++ compilers, like Clang 20 and GCC 15 which created some breaking hcanges for legacy code. For the full list of updates in each release, see the [CHANGELOG](https://github.com/eclipse-paho/paho.mqtt.cpp/blob/master/CHANGELOG.md). ## Contributing Contributions to this project are gladly welcomed and appreciated. Before submitting a Pull Request, please keep three things in mind: - This is an official Eclipse project, so it is required that all contributors sign an [Eclipse Contributor Agreement (ECA)](https://www.eclipse.org/legal/ECA.php) - Please submit all Pull Requests against the _develop_ branch (not master). - Please sign all commits. For full details, see [CONTRIBUTING.md](https://github.com/eclipse/paho.mqtt.cpp/blob/master/CONTRIBUTING.md). ## Building from source As of v1.5, the Paho C++ library uses C++17 features, thus requiring a fully compliant C++17 compiler. Some of the more common compilers that can be used, depending on the target platform, are: * GCC v8 or later * _clang_ v5 or later * Visual Studio 2017 15.8 (MSVC 19.15) or later _CMake_ is a cross-platform build system suitable for Unix and non-Unix platforms such as Microsoft Windows. It is the only supported build system. The current supported minimum version is: * cmake v3.13 The Paho C++ library requires the Paho C library, v1.3.14 or greater to be built and installed. That can be done before building this library, or it can be done here using the CMake `PAHO_WITH_MQTT_C` build option to build both libraries at the same time. This also guarantees that a proper version of the C library is used, and that it is build with compatible options. ### Build Options CMake allows for options to direct the build. The following are specific to Paho C++: Variable | Default Value | Description ------------ | ------------- | ------------- PAHO_BUILD_SHARED | TRUE (*nix), FALSE (Win32) | Whether to build the shared library PAHO_BUILD_STATIC | FALSE (*nix), TRUE (Win32) | Whether to build the static library PAHO_WITH_SSL | TRUE (*nix), FALSE (Win32) | Whether to build SSL/TLS support into the library PAHO_BUILD_DOCUMENTATION | FALSE | Create the HTML API documentation (requires _Doxygen_) PAHO_BUILD_EXAMPLES | FALSE | Whether to build the example programs PAHO_BUILD_TESTS | FALSE | Build the unit tests. (Requires _Catch2_) PAHO_BUILD_DEB_PACKAGE | FALSE | Flag that configures cpack to build a Debian/Ubuntu package PAHO_WITH_MQTT_C | FALSE | Whether to build the bundled Paho C library Enabling `PAHO_WITH_MQTT_C` builds and links in the Paho C library using compatible build options. If this is enabled, it passes the `PAHO_WITH_SSL` option to the C library, and also sets the options `PAHO_HIGH_PERFORMANCE` and `PAHO_WITH_UNIX_SOCKETS` for the C lib. These can be disabled in the cache before building if desired. In addition, the C++ build might commonly use `CMAKE_PREFIX_PATH` to help the build system find the location of the Paho C library if it was built separately. ### Build the Paho C++ and Paho C libraries together The quickest and easiest way to build Paho C++ is to build it together with Paho C in a single step using the included Git submodule. This requires the CMake option `PAHO_WITH_MQTT_C` set. ``` $ git clone https://github.com/eclipse/paho.mqtt.cpp $ cd paho.mqtt.cpp $ git co v1.5.3 $ git submodule init $ git submodule update $ cmake -Bbuild -H. -DPAHO_WITH_MQTT_C=ON -DPAHO_BUILD_EXAMPLES=ON $ sudo cmake --build build/ --target install ``` This assumes the build tools and dependencies, such as OpenSSL, have already been installed. For more details and platform-specific requirements, see below. ### Unix-style Systems (Linux, macOS, etc) On *nix systems CMake creates Makefiles. The build process currently supports a number of Unix and Linux flavors. The build process requires the following tools: * CMake v3.13 or newer * A fully-compatible C++17 compiler. Common options are: * GCC v8 or later * _clang_ v5 or later On Debian based systems this would mean that the following packages have to be installed: ``` $ sudo apt-get install build-essential gcc make cmake ``` If you will be using secure sockets (and you probably should if you're sending messages across a public netwok): ``` $ sudo apt-get install libssl-dev ``` Building the documentation requires doxygen and optionally graphviz to be installed: ``` $ sudo apt-get install doxygen graphviz ``` Unit tests are built using _Catch2_. _Catch2_ can be found here: [Catch2](https://github.com/catchorg/Catch2). You must download and install _Catch2_ to build and run the unit tests locally. Currently _Catch2_ versions v2.x and v3.x are supported. #### Building the Paho C library The Paho C library can be built automatically when building this library by enabling the CMake build option, `PAHO_WITH_MQTT_C`. That will build and install the Paho C library from a Git submodule, using a known-good version, and the proper build configuration for the C++ library. But iIf you want to manually specify the build configuration of the Paho C library or use a different version, then it must be built and installed before building the C++ library. Note, this version of the C++ library requires Paho C v1.3.14 or greater. To download and build the Paho C library: $ git clone https://github.com/eclipse/paho.mqtt.c.git $ cd paho.mqtt.c $ git checkout v1.3.14 $ cmake -Bbuild -H. -DPAHO_ENABLE_TESTING=OFF -DPAHO_WITH_SSL=ON -DPAHO_HIGH_PERFORMANCE=ON $ sudo cmake --build build/ --target install This builds the C library with SSL/TLS enabled. If that is not desired, omit the `-DPAHO_WITH_SSL=ON`. It also uses the "high performance" option of the C library to disable more extensive internal memory checks. Remove the _PAHO_HIGH_PERFORMANCE_ option (i.e. turn it off) to debug memory issues, but for most production systems, leave it on for better performance. The above will install the