Change tarball compression from gzip to bzip2

Set the user and group of all files to root for tar versions which
support it. Add explanatory comments for supporting that feature with
other tar versions.

Use LC_ALL instead of LANG everywhere.

Corresponding to flashrom svn r644.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Stefan Reinauer <stepan@coresystems.de>
diff --git a/Makefile b/Makefile
index fcac2ec..ee5e9ca 100644
--- a/Makefile
+++ b/Makefile
@@ -58,7 +58,7 @@
 # of the checked out flashrom files.
 # Note to packagers: Any tree exported with "make export" or "make tarball"
 # will not require subversion. The downloadable snapshots are already exported.
-SVNVERSION := $(shell LANG=C svnversion -cn . | sed -e "s/.*://" -e "s/\([0-9]*\).*/\1/" | grep "[0-9]" || echo unknown)
+SVNVERSION := $(shell LC_ALL=C svnversion -cn . | sed -e "s/.*://" -e "s/\([0-9]*\).*/\1/" | grep "[0-9]" || echo unknown)
 
 VERSION := 0.9.0-r$(SVNVERSION)
 
@@ -67,9 +67,14 @@
 $(PROGRAM): $(OBJS)
 	$(CC) $(LDFLAGS) -o $(PROGRAM) $(OBJS) $(LIBS) $(FEATURE_LIBS)
 
-FEATURE_CFLAGS = $(shell LANG=C grep -q "FTDISUPPORT := yes" .features && printf "%s" "-D'FT2232_SPI_SUPPORT=1'")
+FEATURE_CFLAGS = $(shell LC_ALL=C grep -q "FTDISUPPORT := yes" .features && printf "%s" "-D'FT2232_SPI_SUPPORT=1'")
 
-FEATURE_LIBS = $(shell LANG=C grep -q "FTDISUPPORT := yes" .features && printf "%s" "-lftdi")
+FEATURE_LIBS = $(shell LC_ALL=C grep -q "FTDISUPPORT := yes" .features && printf "%s" "-lftdi")
+
+# TAROPTIONS reduces information leakage from the packager's system.
+# If other tar programs support command line arguments for setting uid/gid of
+# stored files, they can be handled here as well.
+TAROPTIONS = $(shell LC_ALL=C tar --version|grep -q GNU && echo "--owner=root --group=root")
 
 %.o: %.c .features
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(FEATURE_CFLAGS) $(SVNDEF) -o $@ -c $<
@@ -137,9 +142,9 @@
 	@echo Exported $(EXPORTDIR)/flashrom-$(VERSION)/
 
 tarball: export
-	@tar cfz $(EXPORTDIR)/flashrom-$(VERSION).tar.gz -C $(EXPORTDIR)/ flashrom-$(VERSION)/
+	@tar cjf $(EXPORTDIR)/flashrom-$(VERSION).tar.bz2 -C $(EXPORTDIR)/ $(TAROPTIONS) flashrom-$(VERSION)/
 	@rm -rf $(EXPORTDIR)/flashrom-$(VERSION)
-	@echo Created $(EXPORTDIR)/flashrom-$(VERSION).tar.gz
+	@echo Created $(EXPORTDIR)/flashrom-$(VERSION).tar.bz2
 
 .PHONY: all clean distclean dep compiler pciutils features export tarball