Add exported/installed CMake target

This commit adds the `WIL` CMake interface library, which allows the
project to be exported and installed for consumption by other CMake
projects in the standard fashion.

The logic to create the NuGet package has been replaced with the
built-in CPack NuGet support introduced with CMake 3.13, which
automatically packages any files and directories installed by the
target. This replaces the `make_wil_nupkg` custom target with the
standard CPack `package` target, which builds the package with all the
configured package generators (for now that's just NuGet).

Note that the original NuGet specification file used the new license
style, whereas CPack still generates a NuGet specification with the
deprecated style. This will hopefully be resolved by future versions of
CPack.

Resolves microsoft#118.

CMakeLists.txt

@@ -1,13 +1,14 @@
 cmake_minimum_required(VERSION 3.11)
-project(WIL)
+
+project(WIL
+    VERSION 0.0.0.0
+    DESCRIPTION "The Windows Implementation Libraries (wil) were created to improve productivity and solve problems commonly seen by Windows developers."
+    HOMEPAGE_URL "https://github.com/Microsoft/wil"
+    LANGUAGES CXX)
 
 # Set by build server to speed up build/reduce file/object size
 option(FAST_BUILD "Sets options to speed up build/reduce obj/executable size" OFF)
 
-if (NOT DEFINED WIL_BUILD_VERSION)
-    set(WIL_BUILD_VERSION "0.0.0")
-endif()
-
 # Detect the Windows SDK version. If we're using the Visual Studio generator, this will be provided for us. Otherwise
 # we'll need to assume that this value comes from the command line (e.g. through the VS command prompt)
 if (DEFINED CMAKE_VS_WINDOWS_TARGET_PLATFORM_VERSION)
@@ -17,5 +18,63 @@ else()
     string(REGEX REPLACE "\\\\$" "" WIL_WINDOWS_SDK_VERSION "$ENV{WindowsSDKVersion}")
 endif()
 
-add_subdirectory(packaging)
+add_library(WIL INTERFACE)
+
+target_include_directories(WIL
+    INTERFACE
+        "$<BUILD_INTERFACE:${CMAKE_SOURCE_DIR}/include>"
+        "$<INSTALL_INTERFACE:include>")
+
+install(
+    DIRECTORY "include/"
+    DESTINATION "include")
+
+install(
+    FILES "ThirdPartyNotices.txt"
+    DESTINATION ".")
+
+# Export the targets for consumption by other CMake projects
+
+include(CMakePackageConfigHelpers)
+
+configure_package_config_file(
+        "cmake/WILConfig.cmake.in"
+        "${CMAKE_BINARY_DIR}/cmake/WILConfig.cmake"
+    INSTALL_DESTINATION "cmake")
+
+write_basic_package_version_file(
+        "${CMAKE_BINARY_DIR}/cmake/WILConfigVersion.cmake"
+    COMPATIBILITY ExactVersion ARCH_INDEPENDENT)
+
+install(
+    FILES
+        "${CMAKE_BINARY_DIR}/cmake/WILConfig.cmake"
+        "${CMAKE_BINARY_DIR}/cmake/WILConfigVersion.cmake"
+    DESTINATION "cmake")
+
+export(TARGETS WIL FILE "cmake/WILTargets.cmake")
+
+install(TARGETS WIL EXPORT WILTargets)
+install(EXPORT WILTargets DESTINATION cmake)
+
+# Configure and build the NuGet package
+
+set(CPACK_GENERATOR "NuGet")
+
+set(CPACK_PACKAGE_NAME "Microsoft.Windows.ImplementationLibrary")
+set(CPACK_PACKAGE_DESCRIPTION "${PROJECT_DESCRIPTION}")
+set(CPACK_PACKAGE_DESCRIPTION_SUMMARY "")
+set(CPACK_PACKAGE_VENDOR "Microsoft")
+
+set(CPACK_RESOURCE_FILE_LICENSE "${CMAKE_SOURCE_DIR}/LICENSE")
+set(CPACK_RESOURCE_FILE_README "${CMAKE_SOURCE_DIR}/README.md")
+
+set(CPACK_NUGET_PACKAGE_LICENSEURL "https://github.com/microsoft/wil/blob/master/LICENSE")
+
+set(CPACK_NUGET_PACKAGE_TITLE "Windows Implementation Library")
+set(CPACK_NUGET_PACKAGE_COPYRIGHT "© Microsoft Corporation. All rights reserved.")
+set(CPACK_NUGET_PACKAGE_TAGS "windows utility wil native")
+
+include(CPack)
+
 add_subdirectory(tests)

README.md

@@ -47,6 +47,24 @@ C:\vcpkg> vcpkg install wil:x64-windows
 ```
 Note that even though WIL is a header-only library, you still need to install the package for all architectures/platforms you wish to use it with. Otherwise, WIL won't be added to the include path for the missing architectures/platforms. Execute `vcpkg help triplet` for a list of available options.
 
+## Consuming WIL via CMake
+
+WIL exports and installs a CMake target for use in other CMake projects. You can link your target to WIL with the following:
+
+```cmake
+find_package(WIL)
+
+add_library(MyCMakeTarget PUBLIC WIL)
+```
+
+If CMake is unable to locate WIL automatically, you can configure `WIL_DIR` to ensure it is found:
+
+```cmd
+C:\my\project> cmake -DWIL_DIR=%YOUR_WIL_INSTALL_DIRECTORY%/cmake
+```
+
+These instructions can be combined with the package manager instructions above to consume a stable version of WIL from a CMake project.
+
 # Building/Testing
 To get started testing WIL, first make sure that you have a recent version of [Visual Studio](https://visualstudio.microsoft.com/downloads/) and the most recent [Windows SDK](https://developer.microsoft.com/en-us/windows/downloads/windows-10-sdk) installed. If you are doing
 any non-trivial work, also be sure to have a recent version of [Clang](http://releases.llvm.org/download.html) installed. Once everything is installed, open a VS

cmake/WILConfig.cmake.in

@@ -0,0 +1,3 @@
+@PACKAGE_INIT@
+
+include("${CMAKE_CURRENT_LIST_DIR}/WILTargets.cmake")

scripts/init.cmd

@@ -171,7 +171,7 @@ goto :init
         set CMAKE_ARGS=%CMAKE_ARGS% -DCMAKE_LINKER=lld-link
     )
 
-    if "%VERSION%" NEQ "" set CMAKE_ARGS=%CMAKE_ARGS% -DWIL_BUILD_VERSION=%VERSION%
+    if "%VERSION%" NEQ "" set CMAKE_ARGS=%CMAKE_ARGS% -DCPACK_PACKAGE_VERSION=%VERSION%
 
     if %FAST_BUILD%==1 set CMAKE_ARGS=%CMAKE_ARGS% -DFAST_BUILD=ON