preserve-libs: fix linkmap logic for new plibs

Together with commit f36b9fa38b5268c2a5579db62acec026625f84a9,
hopefully this solves bug #366061.

2 files changed, 40 insertions, 11 deletions

diff --git a/pym/portage/dbapi/vartree.py b/pym/portage/dbapi/vartree.py
index 4170d3dfd..d8fe7b518 100644
--- a/pym/portage/dbapi/vartree.py
+++ b/pym/portage/dbapi/vartree.py
@@ -1434,7 +1434,7 @@ class dblink(object):
 		return pkgfiles
 
 	def _prune_plib_registry(self, unmerge=False, others_in_slot=[],
-		needed=None):
+		needed=None, preserve_paths=None):
 		# remove preserved libraries that don't have any consumers left
 		plib_registry = self.vartree.dbapi._plib_registry
 		if plib_registry:
@@ -1450,7 +1450,7 @@ class dblink(object):
 					exclude_pkgs = None
 
 				self._linkmap_rebuild(exclude_pkgs=exclude_pkgs,
-					include_file=needed)
+					include_file=needed, preserve_paths=preserve_paths)
 
 				cpv_lib_map = self._find_unused_preserved_libs()
 				if cpv_lib_map:
@@ -1476,7 +1476,8 @@ class dblink(object):
 				plib_registry.unlock()
 
 	def unmerge(self, pkgfiles=None, trimworld=None, cleanup=True,
-		ldpath_mtimes=None, others_in_slot=None, needed=None):
+		ldpath_mtimes=None, others_in_slot=None, needed=None,
+		preserve_paths=None):
 		"""
 		Calls prerm
 		Unmerges a given package (CPV)
@@ -1496,6 +1497,11 @@ class dblink(object):
 		@type others_in_slot: list
 		@param needed: Filename containing libraries needed after unmerge.
 		@type needed: String
+		@param preserve_paths: Libraries preserved by a package instance that
+			is currently being merged. They need to be explicitly passed to the
+			LinkageMap, since they are not registered in the
+			PreservedLibsRegistry yet.
+		@type preserve_paths: set
 		@rtype: Integer
 		@returns:
 		1. os.EX_OK if everything went well.
@@ -1629,7 +1635,8 @@ class dblink(object):
 						level=logging.ERROR, noiselevel=-1)
 
 			self._prune_plib_registry(unmerge=True,
-				others_in_slot=others_in_slot, needed=needed)
+				others_in_slot=others_in_slot, needed=needed,
+				preserve_paths=preserve_paths)
 		finally:
 			self.vartree.dbapi._bump_mtime(self.mycpv)
 			if builddir_lock:
@@ -3321,7 +3328,8 @@ class dblink(object):
 			dblnk.settings["REPLACED_BY_VERSION"] = portage.versions.cpv_getversion(self.mycpv)
 			dblnk.settings.backup_changes("REPLACED_BY_VERSION")
 			unmerge_rval = dblnk.unmerge(ldpath_mtimes=prev_mtimes,
-				others_in_slot=others_in_slot, needed=needed)
+				others_in_slot=others_in_slot, needed=needed,
+				preserve_paths=preserve_paths)
 			dblnk.settings.pop("REPLACED_BY_VERSION", None)
 
 			if unmerge_rval == os.EX_OK:
diff --git a/pym/portage/util/_dyn_libs/LinkageMapELF.py b/pym/portage/util/_dyn_libs/LinkageMapELF.py
index bbfce8880..9e79bd888 100644
--- a/pym/portage/util/_dyn_libs/LinkageMapELF.py
+++ b/pym/portage/util/_dyn_libs/LinkageMapELF.py
@@ -142,10 +142,26 @@ class LinkageMapELF(object):
 		def __str__(self):
 			return str(sorted(self.alt_paths))
 
-	def rebuild(self, exclude_pkgs=None, include_file=None):
+	def rebuild(self, exclude_pkgs=None, include_file=None,
+		preserve_paths=None):
 		"""
 		Raises CommandNotFound if there are preserved libs
 		and the scanelf binary is not available.
+
+		@param exclude_pkgs: A set of packages that should be excluded from
+			the LinkageMap, since they are being unmerged and their NEEDED
+			entries are therefore irrelevant and would only serve to corrupt
+			the LinkageMap.
+		@type exclude_pkgs: set
+		@param include_file: The path of a file containing NEEDED entries for
+			a package which does not exist in the vardbapi yet because it is
+			currently being merged.
+		@type include_file: String
+		@param preserve_paths: Libraries preserved by a package instance that
+			is currently being merged. They need to be explicitly passed to the
+			LinkageMap, since they are not registered in the
+			PreservedLibsRegistry yet.
+		@type preserve_paths: set
 		"""
 
 		os = _os_merge
@@ -178,12 +194,17 @@ class LinkageMapELF(object):
 		# have to call scanelf for preserved libs here as they aren't 
 		# registered in NEEDED.ELF.2 files
 		plibs = set()
-		if self._dbapi._plib_registry and self._dbapi._plib_registry.getPreservedLibs():
-			args = ["/usr/bin/scanelf", "-qF", "%a;%F;%S;%r;%n"]
-			for items in self._dbapi._plib_registry.getPreservedLibs().values():
+		if preserve_paths is not None:
+			plibs.update(preserve_paths)
+		if self._dbapi._plib_registry and \
+			self._dbapi._plib_registry.hasEntries():
+			for items in \
+				self._dbapi._plib_registry.getPreservedLibs().values():
 				plibs.update(items)
-				args.extend(os.path.join(root, x.lstrip("." + os.sep)) \
-					for x in items)
+		if plibs:
+			args = ["/usr/bin/scanelf", "-qF", "%a;%F;%S;%r;%n"]
+			args.extend(os.path.join(root, x.lstrip("." + os.sep)) \
+				for x in plibs)
 			try:
 				proc = subprocess.Popen(args, stdout=subprocess.PIPE)
 			except EnvironmentError as e: