Fix "fully support ... own shared libraries" (#1238)

- If shared libraries are built, then fluid, fltk-options, and the
  "games" are linked against the shared FLTK libraries. On some
  platforms the static and the shared versions of fluid and
  fltk-options are built. The games are only built if
  FLTK_BUILD_TEST is enabled.

- The CMake 'install' target now installs the games (if built)
  and their man pages on all platforms (no matter if that is
  useful, for instance on Windows).

- On macOS 'CMAKE_INSTALL_RPATH' is set so *installed* programs
  automatically find their shared FLTK libraries. The "shared"
  versions of fluid and fltk-options got their own '.plist' files.
  This works for both the executables themselves as well as those
  included in bundles. There may be more to do on the macOS platform.

1 files changed, 28 insertions, 39 deletions

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index a445b05fa..00765a79b 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -1,7 +1,7 @@
 #
 # CMakeLists.txt used to build test and demo apps by the CMake build system
 #
-# Copyright 2004-2024 by Bill Spitzak and others.
+# Copyright 2004-2025 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
@@ -84,14 +84,12 @@ fl_create_example(arc arc.cxx fltk::fltk)
 fl_create_example(animated animated.cxx fltk::fltk)
 fl_create_example(ask ask.cxx fltk::fltk)
 fl_create_example(bitmap bitmap.cxx fltk::fltk)
-fl_create_example(blocks "blocks.cxx;blocks.plist;blocks.icns" "fltk::fltk;${AUDIOLIBS}")
 fl_create_example(boxtype boxtype.cxx fltk::fltk)
 fl_create_example(browser browser.cxx fltk::fltk)
 fl_create_example(button button.cxx fltk::fltk)
 fl_create_example(buttons buttons.cxx fltk::fltk)
 # Cairo demo, built with and w/o Cairo (libcairo is linked implicitly - or not at all)
 fl_create_example(cairo_test cairo_test.cxx fltk::fltk)
-fl_create_example(checkers "checkers.cxx;checkers_pieces.fl;checkers.icns" fltk::images)
 fl_create_example(clipboard clipboard.cxx fltk::images)
 fl_create_example(clock clock.cxx fltk::fltk)
 fl_create_example(colbrowser colbrowser.cxx fltk::fltk)
@@ -161,7 +159,6 @@ fl_create_example(resize-example5c "resize-example5c.cxx;resize-arrows.cxx" fltk
 fl_create_example(rotated_text rotated_text.cxx fltk::fltk)
 fl_create_example(scroll scroll.cxx fltk::fltk)
 fl_create_example(subwindow subwindow.cxx fltk::fltk)
-fl_create_example(sudoku "sudoku.cxx;sudoku.plist;sudoku.icns;sudoku.rc" "fltk::images;${AUDIOLIBS}")
 fl_create_example(symbols symbols.cxx fltk::fltk)
 fl_create_example(tabs tabs.fl fltk::fltk)
 fl_create_example(table table.cxx fltk::fltk)
@@ -176,6 +173,14 @@ fl_create_example(valuators valuators.fl fltk::fltk)
 fl_create_example(windowfocus windowfocus.cxx fltk::fltk)
 fl_create_example(wizard wizard.cxx fltk::fltk)
 
+# games
+
+if(NOT FLTK_BUILD_SHARED_LIBS)
+  fl_create_example(blocks "blocks.cxx;blocks.plist;blocks.icns" "fltk::fltk;${AUDIOLIBS}")
+  fl_create_example(checkers "checkers.cxx;checkers_pieces.fl;checkers.icns" fltk::images)
+  fl_create_example(sudoku "sudoku.cxx;sudoku.plist;sudoku.icns;sudoku.rc" "fltk::images;${AUDIOLIBS}")
+endif()
+
 # unittests uses multiple source files and can be built with or w/o OpenGL and "shared"
 
 SET (UNITTEST_SRCS
@@ -213,7 +218,9 @@ if(OPENGL_FOUND)
   fl_create_example(cube cube.cxx "${GLDEMO_LIBS}")
   fl_create_example(fractals "fractals.cxx;fracviewer.cxx" "${GLDEMO_LIBS}")
   fl_create_example(glut_test glut_test.cxx "${GLDEMO_LIBS}")
-  fl_create_example(glpuzzle glpuzzle.cxx "${GLDEMO_LIBS}")
+  if(NOT FLTK_BUILD_SHARED_LIBS)
+    fl_create_example(glpuzzle glpuzzle.cxx "${GLDEMO_LIBS}")
+  endif()
   fl_create_example(gl_overlay gl_overlay.cxx "${GLDEMO_LIBS}")
   fl_create_example(shape shape.cxx "${GLDEMO_LIBS}")
 endif(OPENGL_FOUND)
@@ -268,51 +275,29 @@ if(CMAKE_CXX_COMPILER_ID IN_LIST _compilers)
 endif() # GNU or Clang (-Wshadow test)
 unset(_compilers)
 
-
-# *** EXPERIMENTAL ***
 # Build some of the demo programs linked against the shared FLTK lib(s).
-# This is currently pretty complicated and should be improved.
-# It will be simplified significantly when we use more "modern CMake".
 
 if(FLTK_BUILD_SHARED_LIBS)
 
   if(MSVC) # MS Visual C++ aka. Visual Studio
 
-    # We need to link with fl_call_main.c, but this must not be compiled with
-    # macro FL_DLL, whereas the other source file(s) must be compiled with FL_DLL
-    # to link against the shared libs.
-    #
-    #  ;-)  I *love* Visual Studio (MSVC)  ;-)
-    #
-    # Trick: build an object library with just this one file and link the executable
-    # against the shared library plus this object library. Another way would be to
-    # add the extra source file fl_call_main.c to the source files of all targets
-    # and set the FL_DLL compile_definition property only on the main *source* files
-    # but this doesn't work since the same file must be compiled for the "static"
-    # and the "shared" target, for instance hello.cxx for "hello" and "hello-shared".
-
-    add_library (CALL_MAIN OBJECT EXCLUDE_FROM_ALL ../src/fl_call_main.c)
+    # We need to link with fl_call_main.c which is available as an object
+    # library 'call_main' when built with MSVC (see main CMakeLists.txt).
 
-    # define a list of shared targets so we can set COMPILE_DEFINITIONS in a loop
-    set(SHARED_TARGETS "")
+    fl_create_example(hello-shared hello.cxx "call_main;fltk::fltk-shared")
+    fl_create_example(pixmap_browser-shared pixmap_browser.cxx "call_main;fltk::fltk-shared")
+    fl_create_example(unittests-shared "${UNITTEST_SRCS}" "call_main;${GLDEMO_SHARED}")
 
-    fl_create_example(hello-shared hello.cxx "CALL_MAIN;fltk::fltk-shared")
-    fl_create_example(pixmap_browser-shared pixmap_browser.cxx "CALL_MAIN;fltk::fltk-shared")
-    fl_create_example(unittests-shared "${UNITTEST_SRCS}" "CALL_MAIN;${GLDEMO_SHARED}")
-
-    list(APPEND SHARED_TARGETS hello pixmap_browser unittests)
+    # Games
+    fl_create_example(blocks-shared "blocks.cxx;blocks.plist;blocks.icns" "call_main;fltk::fltk-shared;${AUDIOLIBS}")
+    fl_create_example(checkers-shared "checkers.cxx;checkers_pieces.fl;checkers.icns" "call_main;fltk::fltk-shared")
+    fl_create_example(sudoku-shared "sudoku.cxx;sudoku.plist;sudoku.icns;sudoku.rc" "call_main;fltk::fltk-shared;${AUDIOLIBS}")
 
     if(OPENGL_FOUND)
-      fl_create_example(glpuzzle-shared glpuzzle.cxx "CALL_MAIN;${GLDEMO_SHARED}")
-      fl_create_example(shape-shared shape.cxx "CALL_MAIN;${GLDEMO_SHARED}")
-      list(APPEND SHARED_TARGETS glpuzzle shape)
+      fl_create_example(glpuzzle-shared glpuzzle.cxx "call_main;${GLDEMO_SHARED}")
+      fl_create_example(shape-shared shape.cxx "call_main;${GLDEMO_SHARED}")
     endif(OPENGL_FOUND)
 
-    # apply property COMPILE_DEFINITIONS "-D FL_DLL" in a loop for all necessary source files
-    foreach(tgt ${SHARED_TARGETS})
-      target_compile_definitions (${tgt}-shared PRIVATE "FL_DLL")
-    endforeach()
-
   else() # not MSVC
 
     fl_create_example(cairo_test-shared cairo_test.cxx fltk::fltk-shared)
@@ -320,12 +305,16 @@ if(FLTK_BUILD_SHARED_LIBS)
     fl_create_example(pixmap_browser-shared pixmap_browser.cxx fltk::images-shared)
     fl_create_example(unittests-shared "${UNITTEST_SRCS}" "${GLDEMO_SHARED}")
 
+    # Games
+    fl_create_example(blocks-shared "blocks.cxx;blocks.plist;blocks.icns" "fltk::fltk-shared;${AUDIOLIBS}")
+    fl_create_example(checkers-shared "checkers.cxx;checkers_pieces.fl;checkers.icns" fltk::images-shared)
+    fl_create_example(sudoku-shared "sudoku.cxx;sudoku.plist;sudoku.icns;sudoku.rc" "fltk::images-shared;${AUDIOLIBS}")
+
     if(OPENGL_FOUND)
       fl_create_example(glpuzzle-shared glpuzzle.cxx "${GLDEMO_SHARED}")
       fl_create_example(shape-shared shape.cxx "${GLDEMO_SHARED}")
     endif(OPENGL_FOUND)
 
-
   endif(MSVC) # (not MSVC)
 
 endif(FLTK_BUILD_SHARED_LIBS)