Add a proper build system.

configure.ac

@@ -0,0 +1,61 @@
+AC_INIT(ObjGameKit, 0.1, js@webkeks.org)
+AC_CONFIG_SRCDIR(src)
+
+AC_CHECK_TOOL(OBJFW_CONFIG, objfw-config)
+AS_IF([test x"$OBJFW_CONFIG" = x""], [
+	AC_MSG_ERROR(You need ObjFW and objfw-config installed!)
+])
+
+test x"$OBJC" = x"" && OBJC="$($OBJFW_CONFIG --objc)"
+
+AC_LANG([Objective C])
+AC_PROG_OBJC
+AC_PROG_OBJCPP
+AC_PROG_LN_S
+AC_PROG_INSTALL
+
+CPP="$OBJCPP"
+CPPFLAGS="$CPPFLAGS $OBJCPPFLAGS $($OBJFW_CONFIG --cppflags)"
+OBJCFLAGS="$OBJCFLAGS -Wall $($OBJFW_CONFIG --objcflags)"
+LDFLAGS="$LDFLAGS $($OBJFW_CONFIG --ldflags)"
+LIBS="$LIBS $($OBJFW_CONFIG --libs)"
+
+OBJCFLAGS="$OBJCFLAGS $($OBJFW_CONFIG --arc)"
+AC_MSG_CHECKING([whether Objective C compiler supports ARC])
+AC_TRY_COMPILE([
+	#if !__has_feature(objc_arc)
+	# error No ARC
+	#endif
+	@interface Test
+	@end
+], [
+	__unsafe_unretained Test *t;
+], [
+	AC_MSG_RESULT(yes)
+], [
+	AC_MSG_RESULT(no)
+	AC_MSG_ERROR(You need an Objective C compiler with ARC support!)
+])
+
+PKG_CHECK_MODULES(allegro5, [allegro-5.0 allegro_main-5.0 allegro_image-5.0], [
+	CPPFLAGS="$CPPFLAGS $allegro5_CFLAGS"
+	LIBS="$LIBS $allegro5_LIBS"
+], [
+	AC_MSG_ERROR(You need allegro{_main,_image}-5.0 installed!)
+])
+
+# We add -Werror after all tests in case some tests emit warnings
+OBJCFLAGS="$OBJCFLAGS -Werror"
+
+BUILDSYS_SHARED_LIB
+BUILDSYS_INIT
+BUILDSYS_TOUCH_DEPS
+
+dnl We don't call AC_PROG_CPP, but only AC_PROG_OBJCPP and set CPP to OBJCPP
+dnl and add OBJCPPFLAGS to CPPFLAGS, thus we need to AC_SUBST these ourself.
+AC_SUBST(CPP)
+AC_SUBST(CPPFLAGS)
+
+AC_SUBST(PACKAGE, ObjGameKit)
+AC_CONFIG_FILES(buildsys.mk)
+AC_OUTPUT