Bug #223417 - Make the vardbapi.cpv_all() use_cache parameter useful

for forcing direct os.listdir() calls. This is more of an issue now
that these listdir() calls are frequently triggered when merging
packages (due to things like blocker and preserve-libs handling).
(trunk r10390)

svn path=/main/branches/2.1.2/; revision=10406

2 files changed, 18 insertions, 1 deletions

diff --git a/bin/emerge b/bin/emerge
index dafb3bb66..47c095e89 100755
--- a/bin/emerge
+++ b/bin/emerge
@@ -1163,7 +1163,7 @@ class FakeVartree(portage.vartree):
 				vdb_lock = portage_locks.lockdir(vdb_path)
 			real_dbapi = real_vartree.dbapi
 			slot_counters = {}
-			for cpv in real_dbapi.cpv_all():
+			for cpv in real_dbapi.cpv_all(use_cache=0):
 				cache_key = ("installed", self.root, cpv, "nomerge")
 				pkg = self._pkg_cache.get(cache_key)
 				if pkg is not None:
diff --git a/pym/portage.py b/pym/portage.py
index 85b9bf670..cf38107df 100644
--- a/pym/portage.py
+++ b/pym/portage.py
@@ -6764,8 +6764,25 @@ class vardbapi(dbapi):
 		return returnme
 
 	def cpv_all(self, use_cache=1):
+		"""
+		Set use_cache=0 to bypass the portage.cachedir() cache in cases
+		when the accuracy of mtime staleness checks should not be trusted
+		(generally this is only necessary in critical sections that
+		involve merge or unmerge of packages).
+		"""
 		returnme = []
 		basepath = os.path.join(self.root, VDB_PATH) + os.path.sep
+
+		if use_cache:
+			from portage import listdir
+		else:
+			def listdir(p, **kwargs):
+				try:
+					return [x for x in os.listdir(p) \
+						if os.path.isdir(os.path.join(p, x))]
+				except EnvironmentError:
+					return []
+
 		for x in listdir(basepath, EmptyOnError=1, ignorecvs=1, dirsonly=1):
 			if self._excluded_dirs.match(x) is not None:
 				continue