doc: do not generate latex sources when not needed

configure.ac

@@ -3336,6 +3336,13 @@ AM_CONDITIONAL(STARPU_AVAILABLE_DOC, [test x$available_doc != xno])
 AM_CONDITIONAL(STARPU_BUILD_DOC_PDF, [test x$enable_build_doc_pdf != xno])
 AM_CONDITIONAL(STARPU_AVAILABLE_DOC_PDF, [test x$available_doc_pdf != xno])
 
+if test x$enable_build_doc_pdf != xno ; then
+   DOC_GENERATE_LATEX=YES
+else
+   DOC_GENERATE_LATEX=NO
+fi
+AC_SUBST(DOC_GENERATE_LATEX)
+
 ###############################################################################
 #                                                                             #
 #                                Julia                                        #

doc/doxygen/Makefile.am

@@ -276,12 +276,13 @@ $(DOX_TAG): $(dox_inputs)
 	@if test -f html/navtree.js ; then $(SED) -i 's/\[ "Files", "Files.html", null \]/\[ "", "Files.html", null \]/' html/navtree.js ; fi
 	@$(SED) -i 's/.*"Files.html".*//' html/pages.html
 	@if test -f latex/main.tex ; then mv latex/main.tex latex/index.tex ; fi
-	@$(SED) -i '/\\begin{titlepage}/,$$d' $(DOX_LATEX_DIR)/refman.tex
-	@cat $(top_srcdir)/doc/doxygen/refman.tex >> $(DOX_LATEX_DIR)/refman.tex
+	@if test -f $(DOX_LATEX_DIR)/refman.tex ; then $(SED) -i '/\\begin{titlepage}/,$$d' $(DOX_LATEX_DIR)/refman.tex ; fi
+	@if test -f $(DOX_LATEX_DIR)/refman.tex ; then cat $(top_srcdir)/doc/doxygen/refman.tex >> $(DOX_LATEX_DIR)/refman.tex ; fi
 
 $(DOX_HTML_DIR): $(DOX_TAG)
 
 $(DOX_PDF): $(DOX_TAG) refman.tex $(images)
+	$(MKDIR_P) $(DOX_LATEX_DIR)
 	@cp $(top_srcdir)/doc/doxygen/chapters/version.sty $(DOX_LATEX_DIR)
 	@cp $(top_srcdir)/doc/doxygen/chapters/images/*pdf $(DOX_LATEX_DIR)
 	@echo $(PDFLATEX) $(DOX_LATEX_DIR)/refman.tex

doc/doxygen/doxygen-config.cfg.in

@@ -87,3 +87,4 @@ INPUT_FILTER           = @top_builddir@/doc/doxygen/doxygen_filter.sh
 
 IMAGE_PATH             = @top_srcdir@/doc/doxygen/chapters/images
 
+GENERATE_LATEX         = @DOC_GENERATE_LATEX@

doc/doxygen/doxygen.cfg

@@ -1319,7 +1319,8 @@ EXTRA_SEARCH_MAPPINGS  =
 # If the GENERATE_LATEX tag is set to YES (the default) Doxygen will
 # generate Latex output.
 
-GENERATE_LATEX         = YES
+#defined in doxygen-config.cfg
+#GENERATE_LATEX         = YES
 
 # The LATEX_OUTPUT tag is used to specify where the LaTeX docs will be put.
 # If a relative path is entered the value of OUTPUT_DIRECTORY will be

doc/doxygen_dev/Makefile.am

@@ -211,10 +211,11 @@ $(DOX_TAG): $(dox_inputs)
 	@if test -f html_dev/navtree.js ; then $(SED) -i 's/\[ "Files", "Files.html", null \]/\[ "", "Files.html", null \]/' html_dev/navtree.js ; fi
 	@$(SED) -i 's/.*"Files.html".*//' html_dev/pages.html
 	@if test -f latex/main.tex ; then mv latex/main.tex latex/index.tex ; fi
-	@$(SED) -i '/\\begin{titlepage}/,$$d' $(DOX_LATEX_DIR)/refman.tex
-	@cat $(top_srcdir)/doc/doxygen_dev/refman.tex >> $(DOX_LATEX_DIR)/refman.tex
+	@if test -f $(DOX_LATEX_DIR)/refman.tex ; then $(SED) -i '/\\begin{titlepage}/,$$d' $(DOX_LATEX_DIR)/refman.tex ; fi
+	@if test -f $(DOX_LATEX_DIR)/refman.tex ; then cat $(top_srcdir)/doc/doxygen_dev/refman.tex >> $(DOX_LATEX_DIR)/refman.tex ; fi
 
 $(DOX_PDF): $(DOX_TAG) refman.tex
+	$(MKDIR_P) $(DOX_LATEX_DIR)
 	@cp $(top_srcdir)/doc/doxygen_dev/chapters/version.sty $(DOX_LATEX_DIR)
 	@cp $(top_srcdir)/doc/doxygen_dev/modules.tex $(DOX_LATEX_DIR)
 	@echo $(PDFLATEX) $(DOX_LATEX_DIR)/refman.tex

doc/doxygen_dev/doxygen-config.cfg.in

@@ -134,3 +134,4 @@ INPUT_FILTER           = @top_builddir@/doc/doxygen_dev/doxygen_filter.sh
 
 #IMAGE_PATH             = @top_srcdir@/doc/doxygen_dev/chapters/images
 
+GENERATE_LATEX         = @DOC_GENERATE_LATEX@

doc/doxygen_dev/doxygen.cfg

@@ -1319,7 +1319,8 @@ EXTRA_SEARCH_MAPPINGS  =
 # If the GENERATE_LATEX tag is set to YES (the default) Doxygen will
 # generate Latex output.
 
-GENERATE_LATEX         = YES
+#defined in doxygen-config.cfg
+#GENERATE_LATEX         = YES
 
 # The LATEX_OUTPUT tag is used to specify where the LaTeX docs will be put.
 # If a relative path is entered the value of OUTPUT_DIRECTORY will be