build: add nuget_install() in cmake/NuGet.cmake

This function downloads nuget.exe to out_dir/nuget if necessary and
installs the passed-in NuGet package to that directory.

If the package contains a tools/bin directory, it is added to
CMAKE_PROGRAM_PATH for find_program() to find any utilities.

Add the supporting function file_download() to cmake/Utilities.cmake,
which is a wrapper for the cmake file(DOWNLOAD ...) that takes a
REQUIRED parameter to throw a fatal error if there are any problems.

Signed-off-by: Rafael Kitover <[email protected]>

contrib/buildsystems/cmake/NuGet.cmake

@@ -0,0 +1,73 @@
+include(Utilities)
+
+#
+# nuget_install([pkg_name] [QUIET])
+#
+# Installs nuget.exe in the output directory if not already present
+# and uses it to install pkg_name if provided.
+#
+# If the package contains a 'tools/bin' directory, it will be
+# appended to CMAKE_PROGRAM_PATH.
+#
+# With the QUIET option, no status messages will be printed.
+#
+# Throws a fatal error if any problems are encountered.
+#
+function(nuget_install pkg)
+	if(ARGV1 STREQUAL QUIET)
+		set(quiet TRUE)
+	endif()
+
+	if(NOT EXISTS "${CMAKE_BINARY_DIR}/nuget/nuget.exe")
+		file_download("https://dist.nuget.org/win-x86-commandline/latest/nuget.exe" "${CMAKE_BINARY_DIR}/nuget/nuget.exe" REQUIRED)
+
+		# Add nuget package source if not already present.
+		execute_process(
+			COMMAND nuget sources add -Name "NuGet official package source" -Source "https://api.nuget.org/v3/index.json"
+			WORKING_DIRECTORY "${CMAKE_BINARY_DIR}/nuget"
+			OUTPUT_QUIET
+			ERROR_QUIET
+		)
+	endif()
+
+	if("${pkg}" STREQUAL "")
+		return()
+	endif()
+
+	execute_process(
+		COMMAND nuget.exe install "${pkg}" -OutputDirectory "${CMAKE_BINARY_DIR}/nuget"
+		WORKING_DIRECTORY "${CMAKE_BINARY_DIR}/nuget"
+		OUTPUT_VARIABLE install_output
+		RESULT_VARIABLE install_exit_status
+	)
+
+	if(NOT install_exit_status EQUAL 0)
+		message(FATAL_ERROR "NuGet installation of package '${pkg}' failed, exit code: ${install_exit_status}")
+	endif()
+
+	string(REGEX REPLACE ".* package '[^0-9]+([0-9.]+)'.*" "\\1" pkg_ver "${install_output}")
+
+	set(pkg_dir "${CMAKE_BINARY_DIR}/nuget/${pkg}.${pkg_ver}")
+
+	if(NOT IS_DIRECTORY "${pkg_dir}")
+		message(FATAL_ERROR "NuGet installation of package '${pkg}' failed, package directory '${pkg_dir}' does not exist.")
+	endif()
+
+	if(NOT quiet)
+		message(STATUS "Installed NuGet package '${pkg}' successfully.")
+	endif()
+
+	set(pkg_bin "${pkg_dir}/tools/bin")
+
+	if(IS_DIRECTORY "${pkg_bin}")
+		list(APPEND CMAKE_PROGRAM_PATH "${pkg_bin}")
+		set(CMAKE_PROGRAM_PATH "${CMAKE_PROGRAM_PATH}" PARENT_SCOPE)
+		set(CMAKE_PROGRAM_PATH "${CMAKE_PROGRAM_PATH}" CACHE STRING "External Program Search Path" FORCE)
+
+		if(NOT quiet)
+			message(STATUS "Added tools/bin from NuGet package '${pkg}' to CMAKE_PROGRAM_PATH.")
+		endif()
+	endif()
+endfunction()
+
+# vim:set sw=8 ts=8 noet:

contrib/buildsystems/cmake/Utilities.cmake

@@ -1,3 +1,43 @@
+#
+# file_download(
+#	url dest_path
+#	[STATUS status_out_var]
+#	[REQUIRED]
+# )
+#
+# Wrapper for cmake file(DOWNLOAD ...) with optional error
+# checking. If REQUIRED is passed in, a fatal error will be thrown
+# on failure. Otherwise if STATUS is passed in, it will store the
+# status list in the out var just like file(DOWNLOAD ...).
+#
+function(file_download url dest_path)
+	if(NOT url OR NOT dest_path)
+		message(FATAL_ERROR "file_download: syntax: file_download(url destination_path [OPTIONS]")
+	endif()
+
+	file(DOWNLOAD "${url}" "${dest_path}" STATUS status_list)
+	list(GET status_list 0 status)
+
+	if("STATUS" IN_LIST ARGN)
+		list(FIND ARGN STATUS status_idx)
+		math(EXPR out_var_idx "${status_idx} + 1")
+		list(GET ARGN "${out_var_idx}" out_var)
+
+		if("${out_var}" STREQUAL "")
+			message(FATAL_ERROR "STATUS must be followed by output variable name for the status list.")
+		endif()
+
+		set("${out_var}" "${status_list}" PARENT_SCOPE)
+	endif()
+
+	if ("REQUIRED" IN_LIST ARGN)
+		if(NOT status EQUAL 0)
+			list(GET status_list 1 error_str)
+			message(FATAL_ERROR "Download of '${url}' failed: ${error_str}")
+		endif()
+	endif()
+endfunction()
+
 #
 # build_option(
 #	opt_name type help_string [default]