FindLibUV: Add module to find libuv package

Add it to a private source directory that is not installed so that we
can use it for building CMake itself.  This will allow it to mature
before being distributed publicly.

Source/Modules/FindLibUV.cmake

@@ -0,0 +1,131 @@
+#[=======================================================================[.rst:
+FindLibUV
+---------
+
+Find libuv includes and library.
+
+Imported Targets
+^^^^^^^^^^^^^^^^
+
+An :ref:`imported target <Imported targets>` named
+``LibUV::LibUV`` is provided if libuv has been found.
+
+Result Variables
+^^^^^^^^^^^^^^^^
+
+This module defines the following variables:
+
+``LibUV_FOUND``
+  True if libuv was found, false otherwise.
+``LibUV_INCLUDE_DIRS``
+  Include directories needed to include libuv headers.
+``LibUV_LIBRARIES``
+  Libraries needed to link to libuv.
+``LibUV_VERSION``
+  The version of libuv found.
+``LibUV_VERSION_MAJOR``
+  The major version of libuv.
+``LibUV_VERSION_MINOR``
+  The minor version of libuv.
+``LibUV_VERSION_PATCH``
+  The patch version of libuv.
+
+Cache Variables
+^^^^^^^^^^^^^^^
+
+This module uses the following cache variables:
+
+``LibUV_LIBRARY``
+  The location of the libuv library file.
+``LibUV_INCLUDE_DIR``
+  The location of the libuv include directory containing ``uv.h``.
+
+The cache variables should not be used by project code.
+They may be set by end users to point at libuv components.
+#]=======================================================================]
+
+#=============================================================================
+# Copyright 2014-2016 Kitware, Inc.
+#
+# Distributed under the OSI-approved BSD License (the "License");
+# see accompanying file Copyright.txt for details.
+#
+# This software is distributed WITHOUT ANY WARRANTY; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# See the License for more information.
+#=============================================================================
+# (To distribute this file outside of CMake, substitute the full
+#  License text for the above reference.)
+
+#-----------------------------------------------------------------------------
+find_library(LibUV_LIBRARY
+  NAMES uv
+  )
+mark_as_advanced(LibUV_LIBRARY)
+
+find_path(LibUV_INCLUDE_DIR
+  NAMES uv.h
+  )
+mark_as_advanced(LibUV_INCLUDE_DIR)
+
+#-----------------------------------------------------------------------------
+# Extract version number if possible.
+set(_LibUV_H_REGEX "#[ \t]*define[ \t]+UV_VERSION_(MAJOR|MINOR|PATCH)[ \t]+[0-9]+")
+if(LibUV_INCLUDE_DIR AND EXISTS "${LibUV_INCLUDE_DIR}/uv-version.h")
+  file(STRINGS "${LibUV_INCLUDE_DIR}/uv-version.h" _LibUV_H REGEX "${_LibUV_H_REGEX}")
+elseif(LibUV_INCLUDE_DIR AND EXISTS "${LibUV_INCLUDE_DIR}/uv.h")
+  file(STRINGS "${LibUV_INCLUDE_DIR}/uv.h" _LibUV_H REGEX "${_LibUV_H_REGEX}")
+else()
+  set(_LibUV_H "")
+endif()
+foreach(c MAJOR MINOR PATCH)
+  if(_LibUV_H MATCHES "#[ \t]*define[ \t]+UV_VERSION_${c}[ \t]+([0-9]+)")
+    set(_LibUV_VERSION_${c} "${CMAKE_MATCH_1}")
+  else()
+    unset(_LibUV_VERSION_${c})
+  endif()
+endforeach()
+if(DEFINED _LibUV_VERSION_MAJOR AND DEFINED _LibUV_VERSION_MINOR)
+  set(LibUV_VERSION_MAJOR "${_LibUV_VERSION_MAJOR}")
+  set(LibUV_VERSION_MINOR "${_LibUV_VERSION_MINOR}")
+  set(LibUV_VERSION "${LibUV_VERSION_MAJOR}.${LibUV_VERSION_MINOR}")
+  if(DEFINED _LibUV_VERSION_PATCH)
+    set(LibUV_VERSION_PATCH "${_LibUV_VERSION_PATCH}")
+    set(LibUV_VERSION "${LibUV_VERSION}.${LibUV_VERSION_PATCH}")
+  else()
+    unset(LibUV_VERSION_PATCH)
+  endif()
+else()
+  set(LibUV_VERSION_MAJOR "")
+  set(LibUV_VERSION_MINOR "")
+  set(LibUV_VERSION_PATCH "")
+  set(LibUV_VERSION "")
+endif()
+unset(_LibUV_VERSION_MAJOR)
+unset(_LibUV_VERSION_MINOR)
+unset(_LibUV_VERSION_PATCH)
+unset(_LibUV_H_REGEX)
+unset(_LibUV_H)
+
+#-----------------------------------------------------------------------------
+include(${CMAKE_CURRENT_LIST_DIR}/../../Modules/FindPackageHandleStandardArgs.cmake)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(LibUV
+  FOUND_VAR LibUV_FOUND
+  REQUIRED_VARS LibUV_LIBRARY LibUV_INCLUDE_DIR
+  VERSION_VAR LibUV_VERSION
+  )
+set(LIBUV_FOUND ${LibUV_FOUND})
+
+#-----------------------------------------------------------------------------
+# Provide documented result variables and targets.
+if(LibUV_FOUND)
+  set(LibUV_INCLUDE_DIRS ${LibUV_INCLUDE_DIR})
+  set(LibUV_LIBRARIES ${LibUV_LIBRARY})
+  if(NOT TARGET LibUV::LibUV)
+    add_library(LibUV::LibUV UNKNOWN IMPORTED)
+    set_target_properties(LibUV::LibUV PROPERTIES
+      IMPORTED_LOCATION "${LibUV_LIBRARY}"
+      INTERFACE_INCLUDE_DIRECTORIES "${LibUV_INCLUDE_DIRS}"
+      )
+  endif()
+endif()

Tests/CMakeLists.txt

@@ -1375,6 +1375,10 @@ ${CMake_BINARY_DIR}/bin/cmake -DDIR=dev -P ${CMake_SOURCE_DIR}/Utilities/Release
     add_subdirectory(FindJsonCpp)
   endif()
 
+  if(CMake_TEST_FindLibUV)
+    add_subdirectory(FindLibUV)
+  endif()
+
   if(CMake_TEST_FindLTTngUST)
     add_subdirectory(FindLTTngUST)
   endif()

Tests/FindLibUV/CMakeLists.txt

@@ -0,0 +1,10 @@
+add_test(NAME FindLibUV.Test COMMAND
+  ${CMAKE_CTEST_COMMAND} -C $<CONFIGURATION>
+  --build-and-test
+  "${CMake_SOURCE_DIR}/Tests/FindLibUV/Test"
+  "${CMake_BINARY_DIR}/Tests/FindLibUV/Test"
+  ${build_generator_args}
+  --build-project TestFindLibUV
+  --build-options ${build_options}
+  --test-command ${CMAKE_CTEST_COMMAND} -V -C $<CONFIGURATION>
+  )

Tests/FindLibUV/Test/CMakeLists.txt

@@ -0,0 +1,17 @@
+cmake_minimum_required(VERSION 3.6)
+project(TestFindLibUV C)
+include(CTest)
+
+# CMake does not actually provide FindLibUV publicly.
+set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/../../../Source/Modules)
+
+find_package(LibUV REQUIRED)
+
+add_executable(test_libuv_tgt main.c)
+target_link_libraries(test_libuv_tgt LibUV::LibUV)
+add_test(NAME test_libuv_tgt COMMAND test_libuv_tgt)
+
+add_executable(test_libuv_var main.c)
+target_include_directories(test_libuv_var PRIVATE ${LibUV_INCLUDE_DIRS})
+target_link_libraries(test_libuv_var PRIVATE ${LibUV_LIBRARIES})
+add_test(NAME test_libuv_var COMMAND test_libuv_var)

Tests/FindLibUV/Test/main.c

@@ -0,0 +1,7 @@
+#include <uv.h>
+
+int main()
+{
+  uv_loop_close(uv_default_loop());
+  return 0;
+}