Merge pull request #121 from trapexit/xattr-version

add user.mergerfs.version xattr

Makefile

@@ -106,7 +106,7 @@ help:
 	@echo "usage: make"
 	@echo "make XATTR_AVAILABLE=0 - to build program without xattrs functionality (auto discovered otherwise)"
 
-$(TARGET): obj/obj-stamp $(OBJ)
+$(TARGET): src/version.hpp obj/obj-stamp $(OBJ)
 	$(CXX) $(CFLAGS) $(OBJ) -o $@ $(LDFLAGS)
 
 clonepath: $(TARGET)
@@ -118,6 +118,13 @@ changelog:
 authors:
 	$(GIT) log --format='%aN <%aE>' | sort -f | uniq > AUTHORS
 
+src/version.hpp:
+	$(eval VERSION := $(shell $(GIT) describe --always --tags --dirty))
+	@echo "#ifndef _VERSION_HPP" > src/version.hpp
+	@echo "#define _VERSION_HPP" >> src/version.hpp
+	@echo "static const char MERGERFS_VERSION[] = \"$(VERSION)\";" >> src/version.hpp
+	@echo "#endif" >> src/version.hpp
+
 obj/obj-stamp:
 	$(MKDIR) -p obj
 	$(TOUCH) $@
@@ -163,7 +170,7 @@ $(MANPAGE): README.md
 
 man: $(MANPAGE)
 
-tarball: clean man changelog authors
+tarball: clean man changelog authors src/version.hpp
 	$(eval VERSION := $(shell $(GIT) describe --always --tags --dirty))
 	$(eval VERSION := $(subst -,_,$(VERSION)))
 	$(eval FILENAME := $(TARGET)-$(VERSION))

src/getxattr.cpp

@@ -40,6 +40,7 @@
 #include "rwlock.hpp"
 #include "xattr.hpp"
 #include "str.hpp"
+#include "version.hpp"
 
 using std::string;
 using std::vector;
@@ -134,6 +135,13 @@ _getxattr_controlfile_policies(const Config &config,
     attrvalue += ',' + (string)Policy::policies[i];
 }
 
+static
+void
+_getxattr_controlfile_version(string &attrvalue)
+{
+  attrvalue = MERGERFS_VERSION;
+}
+
 static
 int
 _getxattr_controlfile(const Config &config,
@@ -158,6 +166,8 @@ _getxattr_controlfile(const Config &config,
         _getxattr_controlfile_minfreespace(config,attrvalue);
       else if(attr[2] == "policies")
         _getxattr_controlfile_policies(config,attrvalue);
+      else if(attr[2] == "version")
+        _getxattr_controlfile_version(attrvalue);
       break;
 
     case 4:

src/listxattr.cpp

@@ -53,7 +53,8 @@ _listxattr_controlfile(char         *list,
     buildvector<string>
     ("user.mergerfs.srcmounts")
     ("user.mergerfs.minfreespace")
-    ("user.mergerfs.policies");
+    ("user.mergerfs.policies")
+    ("user.mergerfs.version");
 
   xattrs.reserve(512);
   for(size_t i = 0; i < strs.size(); i++)