commit 54213b95fe4262fb7a1d0d857da1723953cba9cc
Author:     Albrecht Schlosser <albrechts.fltk@online.de>
AuthorDate: Tue Sep 21 20:28:02 2021 +0200
Commit:     Albrecht Schlosser <albrechts.fltk@online.de>
CommitDate: Tue Sep 21 20:28:02 2021 +0200

    Doxygen docs: convert doxygen input file to current version
    
    CMake only: "current" version means the doxygen version available
    on the system where docs are generated.
    
    Todo: do the same for autoconf/make builds.

 documentation/CMakeLists.txt | 43 ++++++++++++++++++++++++++++++++++---------
 1 file changed, 34 insertions(+), 9 deletions(-)

diff --git documentation/CMakeLists.txt documentation/CMakeLists.txt
index 1fa54e1..41ed629 100644
--- documentation/CMakeLists.txt
+++ documentation/CMakeLists.txt
@@ -37,21 +37,33 @@ if (OPTION_BUILD_HTML_DOCUMENTATION)
   set (LATEX_HEADER   "")
 
   configure_file (
+    ${CMAKE_CURRENT_SOURCE_DIR}/src/tiny.png
+    ${CMAKE_CURRENT_BINARY_DIR}/html/tiny.png
+    COPYONLY
+  )
+
+  # configure Doxygen input file for HTML docs (Doxyfile.in)
+
+  configure_file (
     ${CMAKE_CURRENT_SOURCE_DIR}/Doxyfile.in
-    ${CMAKE_CURRENT_BINARY_DIR}/Doxyfile
+    ${CMAKE_CURRENT_BINARY_DIR}/Doxyfile.in
     @ONLY
   )
 
-  configure_file (
-    ${CMAKE_CURRENT_SOURCE_DIR}/src/tiny.png
-    ${CMAKE_CURRENT_BINARY_DIR}/html/tiny.png
-    COPYONLY
+  # convert Doxyfile to current doxygen version
+
+  add_custom_command (
+    OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/Doxyfile
+    COMMAND ${DOXYGEN_EXECUTABLE} -u -s - < Doxyfile.in > Doxyfile
+    WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+    COMMENT "Converting Doxyfile to current doxygen version" VERBATIM
   )
 
-  # generate html docs
+  # generate HTML documentation
 
   add_custom_target (html
-    ${DOXYGEN_EXECUTABLE} ${CMAKE_CURRENT_BINARY_DIR}/Doxyfile
+    COMMAND ${DOXYGEN_EXECUTABLE} Doxyfile
+    DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/Doxyfile
     WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
     COMMENT "Generating HTML documentation" VERBATIM
   )
@@ -66,7 +78,7 @@ if (OPTION_BUILD_PDF_DOCUMENTATION)
 
   list (APPEND DOCS pdf)
 
-  # generate Doxygen file "Doxybook"
+  # generate Doxygen input file "Doxybook"
 
   set (GENERATE_HTML  NO)
   set (GENERATE_LATEX YES)
@@ -79,12 +91,23 @@ if (OPTION_BUILD_PDF_DOCUMENTATION)
     OUTPUT_VARIABLE YEAR
   )
 
+  # configure Doxygen input file for PDF docs (Doxybook.in)
+
   configure_file (
     ${CMAKE_CURRENT_SOURCE_DIR}/Doxyfile.in
-    ${CMAKE_CURRENT_BINARY_DIR}/Doxybook
+    ${CMAKE_CURRENT_BINARY_DIR}/Doxybook.in
     @ONLY
   )
 
+  # convert Doxybook to current doxygen version
+
+  add_custom_command (
+    OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/Doxybook
+    COMMAND ${DOXYGEN_EXECUTABLE} -u -s - < Doxybook.in > Doxybook
+    WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+    COMMENT "Converting Doxybook to current doxygen version" VERBATIM
+  )
+
   # generate LaTeX title fltk-title.tex
 
   configure_file (
@@ -103,6 +126,8 @@ if (OPTION_BUILD_PDF_DOCUMENTATION)
     COMMAND ${DOXYGEN_EXECUTABLE} Doxybook
     COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/make_pdf
     COMMAND cp -f latex/refman.pdf fltk.pdf
+    DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/Doxybook
+            ${CMAKE_CURRENT_BINARY_DIR}/fltk-title.tex
     WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
     COMMENT "Generating PDF documentation" VERBATIM
   )