fix version generation

Makefile

@@ -84,7 +84,7 @@ help:
 	@echo "usage: make"
 	@echo "make XATTR_AVAILABLE=0 - to build program without xattrs functionality (auto discovered otherwise)"
 
-$(TARGET): src/version.hpp obj/obj-stamp libfuse/lib/.libs/libfuse.a $(OBJ)
+$(TARGET): version obj/obj-stamp libfuse/lib/.libs/libfuse.a $(OBJ)
 	cd libfuse && make
 	$(CXX) $(CFLAGS) $(OBJ) -o $@ libfuse/lib/.libs/libfuse.a -ldl $(LDFLAGS)
 
@@ -102,15 +102,7 @@ ifeq ($(GIT_REPO),1)
 endif
 
 version:
-ifeq ($(GIT_REPO),1)
-	$(eval VERSION := $(shell $(GIT) describe --always --tags --dirty))
-	@echo "$(VERSION)" > VERSION
-endif
-
-src/version.hpp: version
-	$(eval VERSION := $(shell cat VERSION))
-	@echo "#pragma once" > src/version.hpp
-	@echo "static const char MERGERFS_VERSION[] = \"$(VERSION)\";" >> src/version.hpp
+	tools/update-version
 
 obj/obj-stamp:
 	$(MKDIR) -p obj
@@ -229,6 +221,6 @@ endif
 libfuse/lib/.libs/libfuse.a: libfuse_Makefile
 	cd libfuse && $(MAKE)
 
-.PHONY: all clean install help
+.PHONY: all clean install help version
 
 -include $(DEPS)

src/getxattr.cpp

@@ -148,6 +148,8 @@ void
 _getxattr_controlfile_version(string &attrvalue)
 {
   attrvalue = MERGERFS_VERSION;
+  if(attrvalue.empty())
+    attrvalue = "unknown_possible_problem_with_build";
 }
 
 static

src/option_parser.cpp

@@ -305,15 +305,6 @@ usage(void)
             << std::endl;
 }
 
-static
-void
-version(void)
-{
-  std::cout << "mergerfs version: "
-            << MERGERFS_VERSION
-            << std::endl;
-}
-
 static
 int
 option_processor(void       *data,
@@ -344,7 +335,9 @@ option_processor(void       *data,
       break;
 
     case MERGERFS_OPT_VERSION:
-      version();
+      std::cout << "mergerfs version: "
+                << (MERGERFS_VERSION[0] ? MERGERFS_VERSION : "unknown")
+                << std::endl;
       fuse_opt_add_arg(outargs,"--version");
       break;
 

tools/update-version

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+GIT=$(which git)
+if [ "${GIT}" = "" ]; then
+    exit 0
+fi
+
+VERSION=$(git describe --always --tags --dirty)
+
+echo -n "${VERSION}" > VERSION
+grep -q \"${VERSION}\" src/version.hpp
+RV=$?
+if [ $RV -ne 0 ]; then
+    echo "#pragma once" > src/version.hpp
+    echo "static const char MERGERFS_VERSION[] = \"${VERSION}\";" >> src/version.hpp
+fi