Convert the manpage to AsciiDoc

Writing DocBook XML by hand is an awful experience and the tools aren't
much better.  Asciidoctor does it well.  There's no need to worry about
semantics, man(1) just needs to be able to show something at all.

This project's manpage is sadly almost useless right now.

CMakeLists.txt

@@ -96,29 +96,24 @@ GETTEXT_CREATE_TRANSLATIONS (
 	ALL ${project_PO_FILES})
 
 # Documentation
-find_program (XSLTPROC_EXECUTABLE xsltproc)
-if (NOT XSLTPROC_EXECUTABLE)
-	message (FATAL_ERROR "xsltproc not found")
-endif (NOT XSLTPROC_EXECUTABLE)
+find_program (ASCIIDOCTOR_EXECUTABLE asciidoctor)
+if (NOT ASCIIDOCTOR_EXECUTABLE)
+	message (FATAL_ERROR "asciidoctor not found")
+endif (NOT ASCIIDOCTOR_EXECUTABLE)
 
-set (project_MAN_PAGES "${PROJECT_NAME}.1")
-foreach (page ${project_MAN_PAGES})
+foreach (page "${PROJECT_NAME}.1")
 	set (page_output "${PROJECT_BINARY_DIR}/${page}")
-	list (APPEND project_MAN_PAGES_OUTPUT "${page_output}")
+	list (APPEND project_MAN_PAGES "${page_output}")
 	add_custom_command (OUTPUT ${page_output}
-		COMMAND ${XSLTPROC_EXECUTABLE}
-			--nonet
-			--param make.year.ranges 1
-			--param make.single.year.ranges 1
-			--param man.charmap.use.subset 0
-			--param man.authors.section.enabled 0
-			http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl
-			"${PROJECT_SOURCE_DIR}/docs/${page}.xml"
-		DEPENDS "docs/${page}.xml"
+		COMMAND ${ASCIIDOCTOR_EXECUTABLE} -b manpage
+			-a release-version=${PROJECT_VERSION}
+			"${PROJECT_SOURCE_DIR}/docs/${page}.adoc"
+			-o "${page_output}"
+		DEPENDS "docs/${page}.adoc"
 		COMMENT "Generating man page for ${page}" VERBATIM)
 endforeach (page)
 
-add_custom_target (docs ALL DEPENDS ${project_MAN_PAGES_OUTPUT})
+add_custom_target (docs ALL DEPENDS ${project_MAN_PAGES})
 
 # Project libraries
 set (project_common_libraries ${ZLIB_LIBRARIES} ${icu_LIBRARIES}
@@ -182,7 +177,7 @@ include (GNUInstallDirs)
 install (TARGETS ${PROJECT_NAME} DESTINATION ${CMAKE_INSTALL_BINDIR})
 install (FILES LICENSE DESTINATION ${CMAKE_INSTALL_DOCDIR})
 
-foreach (page ${project_MAN_PAGES_OUTPUT})
+foreach (page ${project_MAN_PAGES})
 	string (REGEX MATCH "\\.([0-9])$" manpage_suffix "${page}")
 	install (FILES "${page}"
 		DESTINATION "${CMAKE_INSTALL_MANDIR}/man${CMAKE_MATCH_1}")