Expanded CMake Support

This commit introduces several features for the CMake build system.

+ CTest integration
+ CDash integration
+ CPack integration
+ CMake find_package support

To accomodate post-installation consumption, the `include` preprocessor
statements in several library header files were updated to use paths
relative to a root include directory rather than paths relative to the
file itself.

CMakeLists.txt

@@ -1,36 +1,132 @@
-cmake_minimum_required( VERSION 3.2.2 )
-project( mio )
+cmake_minimum_required(VERSION 3.8)
 
-### Standard
-set( CMAKE_CXX_STANDARD 11 )
+#
+# Here we check whether frozen is being configured in isolation or as a component
+# of a larger proeject. To do so, we query whether the `PROJECT_NAME` CMake
+# variable has been defined. In the case it has, we can conclude mio is a
+# subproject.
+#
+# This convention has been borrowed from the Catch C++ unit testing library.
+#
+if(DEFINED PROJECT_NAME)
+  set(subproject ON)
+else()
+  set(subproject OFF)
+endif()
+
+project(mio VERSION 1.0.0 LANGUAGES C CXX)
+include (CTest)
+include (CMakeDependentOption)
 
 # Generate 'compile_commands.json' for clang_complete
-set( CMAKE_EXPORT_COMPILE_COMMANDS ON )
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
-### Flags/Options
-option( BUILD_TESTS "Enable the building of mio unit tests" OFF )
+#
+# The `mio.testing` options only appear as cmake-gui and ccmake options iff
+# mio is the highest level project. In the case that mio is a subproject, these
+# options are hidden from the user interface and set to `OFF`
+#
+# Iff mio is the highest level project, this option is defaulted to the value
+# of the traditional course grain testing option `BUILD_TESTING` established by
+# the CTest module
+#
+CMAKE_DEPENDENT_OPTION(mio.tests
+  "Build the frozen tests and integrate with ctest"
+  ${BUILD_TESTING} "NOT subproject" OFF)
 
-### Library targets
-add_library( mio INTERFACE)
-target_include_directories( mio INTERFACE include )
-install(
-	DIRECTORY include/
-	DESTINATION include
-)
+#
+# mio has no compiled components. As such, we declare it as an `INTERFACE`
+# library, which denotes a collection of target properties to be applied
+# transitively to linking targets. In our case, this amounts to an include
+# directory and project header files.
+#
+add_library(mio INTERFACE)
+add_library(mio::mio ALIAS mio)
 
-### Test targets
-if( BUILD_TESTS )
-	## test
-	add_executable(
-		test
-		test/test.cpp
-	)
-	target_link_libraries( test PRIVATE mio )
-	
-	## example
-	add_executable(
-		example
-		test/example.cpp
-	)
-	target_link_libraries( example PRIVATE mio )
+#
+# mio requires C++ 11 support, at a minimum. Setting the `cxx_std_11` compile
+# features ensures that the corresponding C++ standard flag is populated in
+# targets linking to mio
+#
+target_compile_features(mio INTERFACE cxx_std_11)
+
+#
+# The include directory for mio can be expected to vary between build
+# and installaion. Here we use a CMake generator expression to dispatch
+# on how the configuration under which this library is being consumed.
+#
+target_include_directories(mio INTERFACE
+  $<BUILD_INTERFACE:${CMAKE_CURRENT_LIST_DIR}/include>
+  $<INSTALL_INTERFACE:include>)
+
+add_subdirectory(include/mio)
+
+if(mio.tests)
+  add_subdirectory(test)
 endif()
+
+#
+# Non-testing header files (preserving relative paths) are installed to the
+# `include` subdirectory of the `$INSTALL_DIR/${CMAKE_INSTALL_PREFIX}`
+# directory. Source file permissions preserved.
+#
+install(DIRECTORY include/
+  DESTINATION include
+  USE_SOURCE_PERMISSIONS
+  FILES_MATCHING PATTERN "*.*pp")
+
+#
+# As a header-only library, there are no target components to be installed
+# directly (the PUBLIC_HEADER property is not white listed for INTERFACE
+# targets for some reason).
+#
+# However, it is worthwhile export our target description in order to later
+# generate a CMake configuration file for consumption by CMake's `find_package`
+# intrinsic
+#
+install(TARGETS mio EXPORT mioConfig)
+install(EXPORT mioConfig
+  FILE mioConfig.cmake
+  NAMESPACE mio::
+  DESTINATION share/cmake/mio
+  PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ)
+
+include(CMakePackageConfigHelpers) # provides `write_basic_package_version_file`
+write_basic_package_version_file("mioConfigVersion.cmake"
+  VERSION ${mio_VERSION}
+  COMPATIBILITY SameMajorVersion)
+
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/mioConfigVersion.cmake"
+  DESTINATION share/cmake/mio
+  PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ)
+
+#
+# Rudimentary CPack support.
+#
+# CPack provides a mechanism to generate installation packaging for a project,
+# e.g., self-extracting shell scripts, compressed tarballs, Debian Package files,
+# RPM Package Manager files, Windows NSIS installation wizards,
+# Apple Disk Images (.dmg), etc.
+#
+# Any system libraries required (runtimes, threading, etc) should be bundled
+# with the project for this type of installation. The
+# `InstallRequiredSystemLibraries` CMake module attempts to provide this
+# functionality in an automated way. Additional libraries may be specified as
+#
+# ```cmake
+# list(APPEND CMAKE_INSTALL_SYSTEM_RUNTIME_LIBS <library>)
+# ```
+#
+# A packaged installation can be generated by calling
+#
+# ```sh
+# cpack -G <packaging type> --config CPackConfig.cmake
+# ```
+#
+# See `cpack --help` or the CPack documentation for more information.
+#
+include( InstallRequiredSystemLibraries )
+set( CPACK_PACKAGE_VENDOR "mandreyel" )
+set( CPACK_RESOURCE_FILE_LICENSE "${CMAKE_CURRENT_SOURCE_DIR}/LICENSE" )
+set( CMAKE_PROJECT_HOMEPAGE_URL "https://github.com/mandreyel/mio" )
+include( CPack )

include/mio/CMakeLists.txt

@@ -0,0 +1,11 @@
+target_sources(mio INTERFACE
+  $<BUILD_INTERFACE:
+    ${CMAKE_CURRENT_LIST_DIR}/mmap.hpp
+    ${CMAKE_CURRENT_LIST_DIR}/page.hpp
+    ${CMAKE_CURRENT_LIST_DIR}/shared_mmap.hpp>
+  $<INSTALL_INTERFACE:
+    include/mio/mmap.hpp
+    include/mio/page.hpp
+    include/mio/shared_mmap.hpp>)
+
+add_subdirectory(detail)

include/mio/detail/CMakeLists.txt

@@ -0,0 +1,7 @@
+if(NOT subproject)
+  target_sources(mio INTERFACE
+    $<BUILD_INTERFACE:
+      ${CMAKE_CURRENT_LIST_DIR}/basic_mmap.hpp
+      ${CMAKE_CURRENT_LIST_DIR}/basic_mmap.ipp
+      ${CMAKE_CURRENT_LIST_DIR}/string_util.hpp>)
+endif()

include/mio/detail/basic_mmap.hpp

@@ -21,7 +21,7 @@
 #ifndef MIO_BASIC_MMAP_HEADER
 #define MIO_BASIC_MMAP_HEADER
 
-#include "../page.hpp"
+#include "mio/page.hpp"
 
 #include <iterator>
 #include <string>
@@ -159,6 +159,6 @@ bool operator>=(const basic_mmap<ByteT>& a, const basic_mmap<ByteT>& b);
 } // namespace detail
 } // namespace mio
 
-#include "basic_mmap.ipp"
+#include "mio/detail/basic_mmap.ipp"
 
 #endif // MIO_BASIC_MMAP_HEADER

include/mio/detail/basic_mmap.ipp

@@ -21,9 +21,9 @@
 #ifndef MIO_BASIC_MMAP_IMPL
 #define MIO_BASIC_MMAP_IMPL
 
-#include "basic_mmap.hpp"
-#include "string_util.hpp"
-#include "../page.hpp"
+#include "mio/detail/basic_mmap.hpp"
+#include "mio/detail/string_util.hpp"
+#include "mio/page.hpp"
 
 #include <algorithm>
 #include <cstdint>

include/mio/shared_mmap.hpp

@@ -21,7 +21,7 @@
 #ifndef MIO_SHARED_MMAP_HEADER
 #define MIO_SHARED_MMAP_HEADER
 
-#include "mmap.hpp"
+#include "mio/mmap.hpp"
 
 #include <system_error> // std::error_code
 #include <memory> // std::shared_ptr