Makefile.am: generate vapi

Use g-ir-scanner with header-only. This produces warnings about
unresolved GBytes that make little sense.

Makefile.am

@@ -24,7 +24,22 @@ test_mconn_crypt_vala_SOURCES = test/mconn-crypt-vala-test.vala \
 				src/mconn-crypt.c \
 				src/mconn-crypt.h
 test_mconn_crypt_vala_LDADD = $(MCONNECT_LIBS)
-test_mconn_crypt_vala_CFLAGS = $(MCONNECT_CFLAGS) -Isrc
+test_mconn_crypt_vala_CFLAGS = $(MCONNECT_CFLAGS) -Isrc -I.
 
-VALAFLAGS = $(MCONNECT_VALAFLAGS) --vapidir=src --pkg=mconn-crypt
+VALAFLAGS = $(MCONNECT_VALAFLAGS) --vapidir=. --pkg=mconn-crypt
+
+mconn-crypt.gir: src/mconn-crypt.h
+	rm -f $@
+	g-ir-scanner --header-only -n MConn --symbol-prefix mconn \
+		$< $(filter -I%,$(MCONNECT_CFLAGS)) | \
+		grep -v warning: > $@
+
+mconn-crypt.vapi: mconn-crypt.gir
+	rm -f $@
+	vapigen --library mconn-crypt $<
+
+
+BUILT_SOURCES = mconn-crypt.vapi mconn-crypt.gir
+
+CLEANFILES = $(BUILT_SOURCES)