CMake: refactor and reformat CMake files

- raise minimum CMake version from 2.6.3 to 3.2.3 (Jun 01, 2015)
- indent all CMake files according to the CMP (2 col.)
- refactor FLTK version number definitions and usage
- unify CMake and autoconf/configure variable names:
  - FL_VERSION -> FLTK_VERSION
  - FL_MAJOR_VERSION -> FLTK_VERSION_MAJOR
  - etc. for _MINOR_ and _PATCH_, respectively
  - note: this does not affect FL_VERSION etc. in source code
- generate "export headers" for all libraries (experimental: OFF)
- port some forgotten goodies from branch-1.3 to master
- merge and improve macro 'create_example' (WIP)
- remove "temporary" options and code for older CMake versions
- include and use 'GenerateExportHeader' (experimental, WIP: OFF)
  - note: created header files are not yet used
- build only *one* DLL with Visual Studio (tested, works)
  - similar to the bundled IDE projects in 1.3.x
- add some dynamically linked test/demo programs ('*-shared')
  if shared libraries are built (WIP)
- split 'macros.cmake': use one file per macro

1 files changed, 93 insertions, 108 deletions

diff --git a/CMake/setup.cmake b/CMake/setup.cmake
index 8935ed2bf..db661a54f 100644
--- a/CMake/setup.cmake
+++ b/CMake/setup.cmake
@@ -2,7 +2,7 @@
 # CMakeLists.txt to build the FLTK project using CMake (www.cmake.org)
 # Written by Michael Surette
 #
-# Copyright 1998-2018 by Bill Spitzak and others.
+# Copyright 1998-2020 by Bill Spitzak and others.
 #
 # This library is free software. Distribution and use rights are outlined in
 # the file "COPYING" which should have been included with this file.  If this
@@ -19,52 +19,37 @@
 # basic setup
 #######################################################################
 
-# The FLTK version
-set(FLTK_VERSION_MAJOR "1")
-set(FLTK_VERSION_MINOR "4")
-set(FLTK_VERSION_PATCH "0")
-set(FLTK_VERSION "${FLTK_VERSION_MAJOR}.${FLTK_VERSION_MINOR}")
-set(FLTK_VERSION_FULL "${FLTK_VERSION}.${FLTK_VERSION_PATCH}")
-
-set(EXECUTABLE_OUTPUT_PATH ${CMAKE_CURRENT_BINARY_DIR}/bin)
-set(LIBRARY_OUTPUT_PATH ${CMAKE_CURRENT_BINARY_DIR}/lib)
-set(ARCHIVE_OUTPUT_PATH ${CMAKE_CURRENT_BINARY_DIR}/lib)
+set (EXECUTABLE_OUTPUT_PATH ${CMAKE_CURRENT_BINARY_DIR}/bin)
+set (LIBRARY_OUTPUT_PATH ${CMAKE_CURRENT_BINARY_DIR}/lib)
+set (ARCHIVE_OUTPUT_PATH ${CMAKE_CURRENT_BINARY_DIR}/lib)
 
 # Search for modules in the FLTK source dir first
-set(CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/CMake")
+set (CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/CMake")
 
-set(FLTK_INCLUDE_DIRS ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR})
-include_directories(${FLTK_INCLUDE_DIRS})
+set (FLTK_INCLUDE_DIRS ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR})
+include_directories (${FLTK_INCLUDE_DIRS})
 
 # Remember root of FLTK source directory in case we're in a subdirectory.
 # Used for instance to find the source directory for doxygen docs
-set(FLTK_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
-
-# Setup install locations
-if(CMAKE_VERSION VERSION_GREATER 2.8.4)
-    # Use GNUInstallDirs if available.
-    include(GNUInstallDirs)
-else()
-    # Else set reasonable defaults.
-    set(CMAKE_INSTALL_BINDIR bin)
-    set(CMAKE_INSTALL_LIBDIR lib)
-    set(CMAKE_INSTALL_INCLUDEDIR include)
-    set(CMAKE_INSTALL_DATADIR share)
-    set(CMAKE_INSTALL_MANDIR share/man)
-endif(CMAKE_VERSION VERSION_GREATER 2.8.4)
-
-set(FLTK_BINDIR ${CMAKE_INSTALL_BINDIR} CACHE PATH
-    "Binary install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
-set(FLTK_LIBDIR ${CMAKE_INSTALL_LIBDIR} CACHE PATH
-    "Library install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
-set(FLTK_INCLUDEDIR ${CMAKE_INSTALL_INCLUDEDIR} CACHE PATH
-    "Public header install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
-set(FLTK_DATADIR ${CMAKE_INSTALL_DATADIR} CACHE PATH
-    "Non-arch data install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
-set(FLTK_MANDIR ${CMAKE_INSTALL_MANDIR} CACHE PATH
-    "Manual install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
-set(FLTK_DOCDIR ${CMAKE_INSTALL_DATADIR}/doc CACHE PATH
-    "Non-arch doc install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
+set (FLTK_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
+
+# Setup install locations (requires CMake 2.8.4)
+
+include(GNUInstallDirs)
+
+
+set (FLTK_BINDIR ${CMAKE_INSTALL_BINDIR} CACHE PATH
+  "Binary install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
+set (FLTK_LIBDIR ${CMAKE_INSTALL_LIBDIR} CACHE PATH
+  "Library install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
+set (FLTK_INCLUDEDIR ${CMAKE_INSTALL_INCLUDEDIR} CACHE PATH
+  "Public header install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
+set (FLTK_DATADIR ${CMAKE_INSTALL_DATADIR} CACHE PATH
+  "Non-arch data install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
+set (FLTK_MANDIR ${CMAKE_INSTALL_MANDIR} CACHE PATH
+  "Manual install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
+set (FLTK_DOCDIR ${CMAKE_INSTALL_DATADIR}/doc CACHE PATH
+  "Non-arch doc install path relative to CMAKE_INSTALL_PREFIX unless set to an absolute path.")
 
 
 #######################################################################
@@ -72,56 +57,56 @@ set(FLTK_DOCDIR ${CMAKE_INSTALL_DATADIR}/doc CACHE PATH
 #######################################################################
 
 # set where config files go
-if(WIN32 AND NOT CYGWIN)
-   set(FLTK_CONFIG_PATH CMake)
-elseif(APPLE AND NOT OPTION_APPLE_X11)
-   set(FLTK_CONFIG_PATH FLTK.framework/Resources/CMake)
-else()
-   set(FLTK_CONFIG_PATH ${FLTK_DATADIR}/fltk)
-endif(WIN32 AND NOT CYGWIN)
+if (WIN32 AND NOT CYGWIN)
+  set (FLTK_CONFIG_PATH CMake)
+elseif (APPLE AND NOT OPTION_APPLE_X11)
+  set (FLTK_CONFIG_PATH FLTK.framework/Resources/CMake)
+else ()
+  set (FLTK_CONFIG_PATH ${FLTK_DATADIR}/fltk)
+endif (WIN32 AND NOT CYGWIN)
 
 include(TestBigEndian)
 TEST_BIG_ENDIAN(WORDS_BIGENDIAN)
 
-if(APPLE)
-   set(HAVE_STRCASECMP 1)
-   set(HAVE_DIRENT_H 1)
-   set(HAVE_SNPRINTF 1)
-   set(HAVE_VSNPRINTF 1)
-   set(HAVE_SCANDIR 1)
-   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-deprecated")
-   if(OPTION_APPLE_X11)
-     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -U__APPLE__")
-     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -U__APPLE__")
-     if(${CMAKE_SYSTEM_VERSION} VERSION_GREATER 16.9.0)
-       set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}  -D_LIBCPP_HAS_THREAD_API_PTHREAD")
-     endif(${CMAKE_SYSTEM_VERSION} VERSION_GREATER 16.9.0)
-   elseif(OPTION_APPLE_SDL)
-     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${SDL2_INCLUDE_DIRS} -U__APPLE__")
-     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${SDL2_INCLUDE_DIRS} -U__APPLE__")
-   else()
-     set(__APPLE_QUARTZ__ 1)
-     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -framework Cocoa")
-     set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -framework Cocoa")
-   endif(OPTION_APPLE_X11)
-endif(APPLE)
-
-if(WIN32)
-    # we do no longer define WIN32 or _WIN32 (since FLTK 1.4.0)
-    # ... but if we did, we'd define _WIN32 (since FLTK 1.4.0)
-    # add_definitions(-D_WIN32)
-    if(MSVC)
-        add_definitions(-DWIN32_LEAN_AND_MEAN)
-        add_definitions(-D_CRT_SECURE_NO_WARNINGS)
-        set(BORDER_WIDTH 2)
-    endif(MSVC)
-    if(CMAKE_C_COMPILER_ID STREQUAL GNU)
-        set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-subsystem,windows")
-    endif(CMAKE_C_COMPILER_ID STREQUAL GNU)
-    if(MINGW AND EXISTS /mingw)
-        list(APPEND CMAKE_PREFIX_PATH /mingw)
-    endif(MINGW AND EXISTS /mingw)
-endif(WIN32)
+if (APPLE)
+  set (HAVE_STRCASECMP 1)
+  set (HAVE_DIRENT_H 1)
+  set (HAVE_SNPRINTF 1)
+  set (HAVE_VSNPRINTF 1)
+  set (HAVE_SCANDIR 1)
+  set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-deprecated")
+  if (OPTION_APPLE_X11)
+    set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -U__APPLE__")
+    set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -U__APPLE__")
+    if (${CMAKE_SYSTEM_VERSION} VERSION_GREATER 16.9.0)
+      set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D_LIBCPP_HAS_THREAD_API_PTHREAD")
+    endif (${CMAKE_SYSTEM_VERSION} VERSION_GREATER 16.9.0)
+  elseif (OPTION_APPLE_SDL)
+    set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${SDL2_INCLUDE_DIRS} -U__APPLE__")
+    set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${SDL2_INCLUDE_DIRS} -U__APPLE__")
+  else ()
+    set (__APPLE_QUARTZ__ 1)
+    set (CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -framework Cocoa")
+    set (CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -framework Cocoa")
+  endif (OPTION_APPLE_X11)
+endif (APPLE)
+
+if (WIN32)
+  # we do no longer define WIN32 or _WIN32 (since FLTK 1.4.0)
+  # ... but if we did, we'd define _WIN32 (since FLTK 1.4.0)
+  # add_definitions (-D_WIN32)
+  if (MSVC)
+    add_definitions (-DWIN32_LEAN_AND_MEAN)
+    add_definitions (-D_CRT_SECURE_NO_WARNINGS)
+    set (BORDER_WIDTH 2)
+  endif (MSVC)
+  if (CMAKE_C_COMPILER_ID STREQUAL GNU)
+    set (CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-subsystem,windows")
+  endif (CMAKE_C_COMPILER_ID STREQUAL GNU)
+  if (MINGW AND EXISTS /mingw)
+    list(APPEND CMAKE_PREFIX_PATH /mingw)
+  endif (MINGW AND EXISTS /mingw)
+endif (WIN32)
 
 #######################################################################
 # size of ints
@@ -130,24 +115,24 @@ include(CheckTypeSize)
 CHECK_TYPE_SIZE(short SIZEOF_SHORT)
 CHECK_TYPE_SIZE(int   SIZEOF_INT)
 CHECK_TYPE_SIZE(long  SIZEOF_LONG)
-CHECK_TYPE_SIZE("long long"  HAVE_LONG_LONG)
-
-if(${SIZEOF_SHORT} MATCHES "^2$")
-   set(U16 "unsigned short")
-endif(${SIZEOF_SHORT} MATCHES "^2$")
-
-if(${SIZEOF_INT} MATCHES "^4$")
-   set(U32 "unsigned")
-else()
-   if(${SIZEOF_LONG} MATCHES "^4$")
-      set(U32 "unsigned long")
-   endif(${SIZEOF_LONG} MATCHES "^4$")
-endif(${SIZEOF_INT} MATCHES "^4$")
-
-if(${SIZEOF_INT} MATCHES "^8$")
-   set(U64 "unsigned")
-else()
-   if(${SIZEOF_LONG} MATCHES "^8$")
-      set(U64 "unsigned long")
-   endif(${SIZEOF_LONG} MATCHES "^8$")
-endif(${SIZEOF_INT} MATCHES "^8$")
+CHECK_TYPE_SIZE("long long" HAVE_LONG_LONG)
+
+if (${SIZEOF_SHORT} MATCHES "^2$")
+  set (U16 "unsigned short")
+endif (${SIZEOF_SHORT} MATCHES "^2$")
+
+if (${SIZEOF_INT} MATCHES "^4$")
+  set (U32 "unsigned")
+else ()
+  if (${SIZEOF_LONG} MATCHES "^4$")
+    set (U32 "unsigned long")
+  endif (${SIZEOF_LONG} MATCHES "^4$")
+endif (${SIZEOF_INT} MATCHES "^4$")
+
+if (${SIZEOF_INT} MATCHES "^8$")
+   set (U64 "unsigned")
+else ()
+   if (${SIZEOF_LONG} MATCHES "^8$")
+    set (U64 "unsigned long")
+   endif (${SIZEOF_LONG} MATCHES "^8$")
+endif (${SIZEOF_INT} MATCHES "^8$")