Makes umqtt installable and a find module in CMake. Builds with -fPIC always.

.gitignore

@@ -4,6 +4,7 @@
 
 /build_all/windows/nuget.exe
 /cmake
+/build
 /devdoc/~$o_requirements.docm
 *.jar
 

CMakeLists.txt

@@ -9,6 +9,9 @@ endif()
 
 project(umqtt)
 
+# Build with -fPIC always
+set(CMAKE_POSITION_INDEPENDENT_CODE TRUE)
+
 #making a nice global variable to know if we are on linux or not.
 if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
     set(LINUX TRUE)
@@ -30,6 +33,7 @@ include(ExternalProject)
 option(skip_unittests "set skip_unittests to ON to skip unittests (default is OFF)[if possible, they are always build]" OFF)
 option(compileOption_C "passes a string to the command line of the C compiler" OFF)
 option(compileOption_CXX "passes a string to the command line of the C++ compiler" OFF)
+option(use_installed_dependencies "set use_installed_dependencies to ON to use installed packages instead of building dependencies from submodules" OFF)
 
 #Use solution folders. 
 set_property(GLOBAL PROPERTY USE_FOLDERS ON)
@@ -65,10 +69,7 @@ endif()
 
 message(STATUS "MQTT Target architecture: ${ARCHITECTURE}") 
 
-# Start of variables used during install
-#set (INCLUDE_INSTALL_DIR include CACHE PATH "Include file directory")
-
-add_subdirectory(c-utility)
+include("dependencies.cmake")
 
 enable_testing()
 
@@ -164,11 +165,50 @@ if (NOT ${ARCHITECTURE} STREQUAL "ARM")
 endif()
 
 if (NOT ${skip_unittests})
+    include("dependencies-test.cmake")
     add_subdirectory(tests)
 endif()
 
-if(WIN32)  
-else()  
-    install (TARGETS umqtt DESTINATION lib)  
-    install (FILES ${source_h_files} DESTINATION include/azureiot/azure_umqtt_c)  
-endif (WIN32)  
+if(${use_installed_dependencies})
+    # Set CMAKE_INSTALL_LIBDIR if not defined
+    include(GNUInstallDirs)
+
+    # Install umqtt
+    set(package_location "cmake")
+
+    if(NOT DEFINED CMAKE_INSTALL_LIBDIR)
+        set(CMAKE_INSTALL_LIBDIR "lib")
+    endif()
+
+    install(TARGETS umqtt EXPORT umqttTargets
+        LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+        ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
+        RUNTIME DESTINATION ${CMAKE_INSTALL_LIBDIR}/../bin
+        INCLUDES DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/azureiot
+    )
+    install(FILES ${source_h_files} DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/azureiot/azure_umqtt_c)
+
+    include(CMakePackageConfigHelpers)
+
+    configure_file("configs/${PROJECT_NAME}Config.cmake"
+        "${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}/${PROJECT_NAME}Config.cmake"
+        COPYONLY
+    )
+
+    install(EXPORT umqttTargets
+        FILE
+            "${PROJECT_NAME}Targets.cmake"
+        DESTINATION
+            ${package_location}
+    )
+
+    install(
+        FILES
+            "configs/${PROJECT_NAME}Config.cmake"
+        DESTINATION
+            ${package_location}
+    )
+
+else()
+    message(WARNING "This package may only be installed when 'use_installed_dependencies' is ON")
+endif() 

configs/umqttConfig.cmake

@@ -0,0 +1,8 @@
+#Copyright (c) Microsoft. All rights reserved.
+#Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+include("${CMAKE_CURRENT_LIST_DIR}/umqttTargets.cmake")
+
+get_target_property(UMQTT_INCLUDES umqtt INTERFACE_INCLUDE_DIRECTORIES)
+
+set(UMQTT_INCLUDES ${UMQTT_INCLUDES} CACHE INTERNAL "")

dependencies-test.cmake

@@ -0,0 +1,14 @@
+#Copyright (c) Microsoft. All rights reserved.
+#Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+if(${use_installed_dependencies})
+    #These need to be set for the functions included by c-utility 
+    if(NOT EXISTS "${CMAKE_CURRENT_LIST_DIR}/c-utility/src")
+        message(FATAL_ERROR "c-utility directory is empty. Please pull in all submodules if building unit tests.")
+    endif()
+    set(SHARED_UTIL_SRC_FOLDER "${CMAKE_CURRENT_LIST_DIR}/c-utility/src")
+    set(SHARED_UTIL_FOLDER "${CMAKE_CURRENT_LIST_DIR}/c-utility")
+    set(SHARED_UTIL_ADAPTER_FOLDER "${CMAKE_CURRENT_LIST_DIR}/c-utility/adapters")
+    set_platform_files("${CMAKE_CURRENT_LIST_DIR}/c-utility")
+    find_package(umock_c REQUIRED CONFIG)
+endif()

dependencies.cmake

@@ -0,0 +1,8 @@
+#Copyright (c) Microsoft. All rights reserved.
+#Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+if(${use_installed_dependencies})
+    find_package(azure_c_shared_utility REQUIRED CONFIG)
+else()
+    add_subdirectory(c-utility)
+endif()

readme.md

@@ -9,3 +9,46 @@ azure-mqtt is a general purpose library build for MQTT protocol
 azure-mqtt client use the azure-c-shared-utility, which is a C library provisioning common functionality for basic tasks (like string, list manipulation, IO, etc.).
 azure-c-shared-utility is available here: https://github.com/Azure/azure-c-shared-utility.
 azure-c-shared-utility needs to be built before building azure-mqtt-c.  
+
+## Setup
+
+- Clone azure-umqtt-c by:
+```
+git clone --recursive https://github.com/Azure/azure-umqtt-c.git
+```
+- Create a folder build under azure-umqtt-c
+- Switch to the build folder and run
+   cmake ..
+
+### Installation and Use
+Optionally, you may choose to install azure-umqtt-c on your machine:
+
+1. Switch to the *cmake* folder and run
+    ```
+    cmake -Duse_installed=ON ../
+    ```
+    ```
+    cmake --build . --target install
+    ```
+    
+    or install using the follow commands for each platform:
+
+    On Linux:
+    ```
+    sudo make install
+    ```
+
+    On Windows:
+    ```
+    msbuild /m INSTALL.vcxproj
+    ```
+
+2. Use it in your project (if installed)
+    ```
+    find_package(umqtt REQUIRED CONFIG)
+    target_link_library(yourlib umqtt)
+    ```
+
+_This requires that azure-c-shared-utility is installed (through CMake) on your machine._
+
+_If running tests, this requires that umock-c, azure-ctest, and azure-c-testrunnerswitcher are installed (through CMake) on your machine._