libdm: new dm_task_get_info with internal_suspend

Introduce new implmentation of dm_task_get_info() function
with support for reading internal_suspend.
.
This time it is done in a 'versioned' way.

We keep the old fashion dm_task_get_info(Base) to implement
the old behavior of 1.02.95 libdm code.

libdm version 1.02.96 introduced 'macro' wrapper
dm_task_get_info_with_deferred_remove with new implementation
of dm_task_get_info() - we cannot do anything else then to
provide compatible version of this symbol.

Now in version 1.02.97 we add new versioned implementation of
dm_task_get_info(DM_1_02_97) symbol.

This has the effect that i.e. rpm build will finaly resolve proper
dependency on a new symbol - so it will be no longer possible,
to build a new binary and use old library
(rpm -q --provides will show libdevmapper.so.1.02(DM_1_02_97)(64bit))

Also the history is now tracked. If a new function is added (or
reimplemented), it needs to be placed in proper file,
so it could be exported with right versioning symbol.
File .exported_symbols.Base should and any existing older DM
should be treated as read-only after a release.

Also - only libdm has been currently enhanced with versioned .Base
file, as soon as other libs (liblvm, libdevmapper-event) needs changes
they should also get their exported symbol files - meanwhile
make.tmpl handles both cases.

1 files changed, 19 insertions, 2 deletions

diff --git a/make.tmpl.in b/make.tmpl.in
index 4311490c6..33d79c2e6 100644
--- a/make.tmpl.in
+++ b/make.tmpl.in
@@ -485,7 +485,7 @@ distclean: cleandir $(SUBDIRS.distclean)
 	test -z "$(DISTCLEAN_DIRS)" || $(RM) -r $(DISTCLEAN_DIRS)
 	$(RM) $(DISTCLEAN_TARGETS) Makefile
 
-.exported_symbols_generated: $(EXPORTED_HEADER) .exported_symbols
+.exported_symbols_generated: $(EXPORTED_HEADER) .exported_symbols $(DEPS)
 	set -e; \
 	( cat $(srcdir)/.exported_symbols; \
 	  if test x$(EXPORTED_HEADER) != x; then \
@@ -494,11 +494,28 @@ distclean: cleandir $(SUBDIRS.distclean)
 	  fi \
 	) > $@
 
+EXPORTED_UC := $(shell echo $(EXPORTED_FN_PREFIX) | tr '[a-z]' '[A-Z]')
+EXPORTED_FILES := $(wildcard $(srcdir)/.exported_symbols.Base $(srcdir)/.exported_symbols.$(EXPORTED_UC)_[0-9_]*[0-9])
+
+ifeq (0,$(words $(EXPORTED_FILES)))
 .export.sym: .exported_symbols_generated
 	set -e; (echo "Base {"; echo "	global:"; \
-		 sed "s/^/		/;s/$$/;/" < $<; \
+		 $(SED) "s/^/		/;s/$$/;/" < $<; \
 		 echo "	local:"; echo "		*;"; echo "};") > $@
 
+else
+.export.sym: .exported_symbols_generated $(EXPORTED_FILES)
+	set -e; \
+	R=$(shell sort $^ | uniq -u);\
+	test -z "$$R" || { echo "Mismatch between symbols in shared library and lists in .exported_symbols.* files: $$R"; false; } ;\
+	(for i in $(EXPORTED_FILES) ; do\
+		echo "$${i##*.} {"; echo "	global:";\
+		$(SED) "s/^/		/;s/$$/;/" < $$i;\
+		test "$$i" = Base && { echo "	local:"; echo "		*;"; };\
+		echo "};";\
+	done ) > $@
+endif
+
 ifeq (,$(findstring $(MAKECMDGOALS),cscope.out cflow clean distclean lcov \
  help check check_local check_cluster check_lvmetad check_lvmpolld))
     ifdef SOURCES