Bug #203090 - Do not trust the global counter
authorZac Medico <zmedico@gentoo.org>
Tue, 25 Dec 2007 02:51:44 +0000 (02:51 -0000)
committerZac Medico <zmedico@gentoo.org>
Tue, 25 Dec 2007 02:51:44 +0000 (02:51 -0000)
file that can lead to invalid COUNTER generation.

svn path=/main/trunk/; revision=9052

pym/portage/dbapi/vartree.py

index 3bd92c8ba3a78277183b29a780824cded01f5d10..1c9aace28ea662c5698d82348ff56175a95feada 100644 (file)
@@ -597,7 +597,28 @@ class vardbapi(dbapi):
                return self.counter_tick_core(myroot, incrementing=1, mycpv=mycpv)
 
        def get_counter_tick_core(self, myroot, mycpv=None):
-               return self.counter_tick_core(myroot, incrementing=0, mycpv=mycpv) + 1
+               """
+               Use this method to retrieve the counter instead
+               of having to trust the value of a global counter
+               file that can lead to invalid COUNTER
+               generation. When cache is valid, the package COUNTER
+               files are not read and we rely on the timestamp of
+               the package directory to validate cache. The stat
+               calls should only take a short time, so performance
+               is sufficient without having to rely on a potentially
+               corrupt global counter file.
+               """
+               cp_list = self.cp_list
+               max_counter = 0
+               for cp in self.cp_all():
+                       for cpv in cp_list(cp):
+                               try:
+                                       counter = int(self.aux_get(cpv, ["COUNTER"])[0])
+                               except (KeyError, OverflowError, ValueError):
+                                       continue
+                               if counter > max_counter:
+                                       max_counter = counter
+               return max_counter + 1
 
        def counter_tick_core(self, myroot, incrementing=1, mycpv=None):
                "This method will grab the next COUNTER value and record it back to the global file.  Returns new counter value."
@@ -619,22 +640,25 @@ class vardbapi(dbapi):
                                writemsg("!!! COUNTER file is corrupt: '%s'\n" % cpath,
                                        noiselevel=-1)
 
+               real_counter = self.get_counter_tick_core(myroot, mycpv=mycpv) - 1
+
                if counter < 0:
                        changed = True
-                       max_counter = 0
-                       cp_list = self.cp_list
-                       for cp in self.cp_all():
-                               for cpv in cp_list(cp):
-                                       try:
-                                               counter = int(self.aux_get(cpv, ["COUNTER"])[0])
-                                       except (KeyError, OverflowError, ValueError):
-                                               continue
-                                       if counter > max_counter:
-                                               max_counter = counter
-                       counter = max_counter
                        writemsg("!!! Initializing COUNTER to " + \
                                "value of %d\n" % counter, noiselevel=-1)
 
+               if counter != real_counter:
+                       changed = True
+                       writemsg("!!! Initializing COUNTER to " + \
+                               "value of %d\n" % counter, noiselevel=-1)
+
+               # Never trust the counter file, since having a
+               # corrupt value that is too low there can trigger
+               # incorrect AUTOCLEAN behavior due to newly installed
+               # packages having lower counters than the previous
+               # version in the same slot.
+               counter = real_counter
+
                if incrementing or changed:
 
                        #increment counter