autotools: add translate target for qt translations

src/Makefile.am

@@ -58,6 +58,10 @@ leveldb/libmemenv.a:
 	@echo "Building LevelDB ..." && cd leveldb && CXX="$(CXX)" CC="$(CC)" \
 	  PLATFORM=$(TARGET_OS) AR="$(AR)" $(MAKE) $(LEVELDB_TARGET_FLAGS) OPT="$(CXXFLAGS) $(CPPFLAGS)" libmemenv.a
 
+qt/bitcoinstrings.cpp: $(libbitcoin_a_SOURCES)
+	@test -n $(XGETTEXT) || echo "xgettext is required for updating translations"
+	@cd $(top_srcdir); XGETTEXT=$(XGETTEXT) share/qt/extract_strings_qt.py
+
 CLEANFILES = leveldb/libleveldb.a leveldb/libmemenv.a *.gcda *.gcno
 
 DISTCLEANFILES = obj/build.h

src/qt/Makefile.am

@@ -153,8 +153,16 @@ QT_FORMS_H=$(join $(dir $(QT_FORMS_UI)),$(addprefix ui_, $(notdir $(QT_FORMS_UI:
 #locale/foo.ts -> locale/foo.qm
 QT_QM=$(QT_TS:.ts=.qm)
 
+.PHONY: FORCE
 .SECONDARY: $(QT_QM)
 
+bitcoinstrings.cpp: FORCE
+	$(MAKE) -C $(top_srcdir)/src qt/bitcoinstrings.cpp
+
+translate: bitcoinstrings.cpp $(QT_FORMS_UI) $(QT_FORMS_UI) $(BITCOIN_QT_CPP) $(BITCOIN_QT_H) $(BITCOIN_MM) $(QR_CPP)
+	@test -n $(LUPDATE) || echo "lupdate is required for updating translations"
+	@$(LUPDATE) $^ -locations relative -no-obsolete -ts locale/bitcoin_en.ts
+
 $(QT_QRC_CPP): $(QT_QRC) $(QT_QM) $(QT_FORMS_H) $(RES_ICONS) $(RES_IMAGES) $(RES_MOVIES) $(PROTOBUF_H)
 	@cd $(abs_srcdir); test -f $(RCC) && $(RCC) -name bitcoin -o $(abs_builddir)/$@ $< || \
 	  echo error: could not build $@