doc: initial effort to enable doxygen

Framework from libuEv.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

configure.ac

@@ -5,7 +5,7 @@ AM_SILENT_RULES([yes])
 
 AC_CONFIG_SRCDIR(src/lite.h)
 AC_CONFIG_HEADERS(config.h)
-AC_CONFIG_FILES([Makefile src/Makefile src/libite.pc test/Makefile])
+AC_CONFIG_FILES([Makefile doc/Makefile doc/Doxyfile src/Makefile src/libite.pc test/Makefile])
 AC_CONFIG_MACRO_DIR([m4])
 
 AC_PROG_CC
@@ -13,4 +13,21 @@ AC_PROG_INSTALL
 m4_ifdef([AM_PROG_AR], [AM_PROG_AR])
 LT_INIT
 
+# Check for Doxygen and enable its features.
+# For details, see m4/ax_prog_doxygen.m4 and
+# http://www.bioinf.uni-freiburg.de/~mmann/HowTo/automake.html#doxygenSupport
+DX_DOXYGEN_FEATURE(ON)
+DX_DOT_FEATURE(OFF)
+DX_CHI_FEATURE(OFF)
+DX_RTF_FEATURE(OFF)
+DX_XML_FEATURE(OFF)
+DX_PDF_FEATURE(OFF)
+DX_PS_FEATURE(OFF)
+DX_CHM_FEATURE(OFF)
+DX_HTML_FEATURE(ON)
+DX_MAN_FEATURE(OFF)
+DX_INIT_DOXYGEN(${PACKAGE_NAME}, [${top_builddir}/doc/Doxyfile], [${top_builddir}/doc])
+AM_CONDITIONAL(ENABLE_DOXYGEN,[test "x${DX_FLAG_doc}" = x1])
+AM_CONDITIONAL(ENABLE_HTML,[test "x${DX_FLAG_html}" = x1])
+
 AC_OUTPUT