build: add support for installing from CMake

We can now install the library, manpage, and pkg-config data from CMake.
At this point, for Linux, FreeBSD, Windows, and android, cmake is
sufficient and should be treated as the canonical build system.

Bump CMake requirement to 3.4.3.  This should be old enough to be
generally available and matches what LLVM, clang, and swift support as a
minimum requirement.

Author: compnerd

CMakeLists.txt

@@ -14,10 +14,10 @@
 # OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #
 
-cmake_minimum_required(VERSION 2.8.4)
+cmake_minimum_required(VERSION 3.4.3)
 cmake_policy(SET CMP0063 OLD)
 
-project(pthread_workqueue C)
+project(pthread_workqueue VERSION 0.9.4 LANGUAGES C)
 
 set(CMAKE_C_VISIBILITY_PRESET hidden)
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
@@ -32,6 +32,7 @@ set(THREADS_PREFER_PTHREADS_FLAG TRUE)
 find_package(Threads REQUIRED)
 
 include(CheckIncludeFiles)
+include(GNUInstallDirs)
 
 if(ENABLE_TESTS)
   check_include_files(err.h HAVE_ERR_H)
@@ -136,3 +137,23 @@ if(ENABLE_TESTS)
   add_subdirectory(testing)
 endif()
 
+configure_file("${PROJECT_SOURCE_DIR}/libpthread_workqueue.pc.in"
+               "${CMAKE_BINARY_DIR}/libpthread_workqueue.pc")
+
+install(TARGETS
+          pthread_workqueue
+        DESTINATION
+          ${CMAKE_INSTALL_FULL_LIBDIR})
+install(FILES
+          ${PTHREAD_WORKQUEUE_HEADERS}
+        DESTINATION
+          ${CMAKE_INSTAL_FULL_INCLUDEDIR})
+install(FILES
+          ${PROJECT_SOURCE_DIR}/pthread_workqueue.3
+        DESTINATION
+          ${CMAKE_INSTALL_FULL_MANDIR})
+install(FILES
+          ${CMAKE_BINARY_DIR}/libpthread_workqueue.pc
+        DESTINATION
+          ${CMAKE_INSTALL_FULL_LIBDIR}/pkgconfig)
+

libpthread_workqueue.pc.in

@@ -1,11 +1,11 @@
-prefix=@@PREFIX@@
+prefix=@CMAKE_INSTALL_PREFIX@
 exec_prefix=${prefix}
-libdir=@@LIBDIR@@
-includedir=@@INCLUDEDIR@@
+libdir=@CMAKE_INSTALL_FULL_LIBDIR@
+includedir=@CMAKE_INSTALL_FULL_INCLUDEDIR@
 
-Name: @@PROGRAM@@
+Name: pthread_workqueue
 Description: Emulates pthread_workqueue(3) API
-Version: @@VERSION@@
-Requires: 
-Libs: @@LIBDEPENDS@@ -lpthread
-Libs.private: @@LIBDEPENDS@@
+Version: @PROJECT_VERSION@
+Requires:
+Libs: -lpthread
+Libs.private: