[Zope3-checkins] CVS: Zope3/src/zodb/storage/file - copy.py:1.3.2.1 main.py:1.2.2.2

[Jeremy Hylton]

Update of /cvs-repository/Zope3/src/zodb/storage/file
In directory cvs.zope.org:/tmp/cvs-serv13942

Modified Files:
      Tag: jeremy-query-branch
	copy.py main.py 
Log Message:
Eliminate _packt variable.

This means it isn't possible to perform undo at any time during a
pack().


=== Zope3/src/zodb/storage/file/copy.py 1.3 => 1.3.2.1 ===
--- Zope3/src/zodb/storage/file/copy.py:1.3	Fri Apr 25 15:28:46 2003
+++ Zope3/src/zodb/storage/file/copy.py	Wed Apr 30 18:08:25 2003
@@ -54,9 +54,7 @@
             if _tid == tid:
                 return pos
             if stop_at_pack:
-                # check the status field of the transaction header
-                # XXX _packt seems to be either ZERO or None
-                if h[16] == 'p' or _tid < self._packt:
+                if h[16] == 'p':
                     break
         raise UndoError(None, "Invalid transaction id")
 


=== Zope3/src/zodb/storage/file/main.py 1.2.2.1 => 1.2.2.2 ===
--- Zope3/src/zodb/storage/file/main.py:1.2.2.1	Wed Apr 30 15:09:49 2003
+++ Zope3/src/zodb/storage/file/main.py	Wed Apr 30 18:08:25 2003
@@ -65,8 +65,6 @@
         self._file = afile
 
 class FileStorage(BaseStorage, DataCopier):
-    # default pack time is 0
-    _packt = ZERO
 
     __implements__ = IStorage, IUndoStorage, IVersionStorage
 
@@ -90,6 +88,10 @@
             stop=MAXTID
 
         self._file_name = file_name
+        # pack() and UndoSearch() are mutually exclusive, so use
+        # each must check the other's flag before starting.
+        self._packing = False
+        self._undoing = False
         super(FileStorage, self).__init__(file_name)
         self._initIndex()
         if not read_only:
@@ -710,10 +712,10 @@
             last = first - last + 1
         self._lock_acquire()
         try:
-            if self._packt is None:
+            if self._packing:
                 raise UndoError("Can't undo during pack")
-            us = UndoSearch(self._file, self._pos, self._packt,
-                            first, last, filter)
+            self._undoing = False
+            us = UndoSearch(self._file, self._pos, first, last, filter)
             while not us.finished():
                 # Hold lock for batches of 20 searches, so default search
                 # parameters will finish without letting another thread run.
@@ -727,6 +729,7 @@
                 self._lock_acquire()
             return us.results
         finally:
+            self._undoing = False
             self._lock_release()
 
     def undo(self, transaction_id, transaction):
@@ -748,6 +751,8 @@
 
         self._lock_acquire()
         try:
+            if self._packing:
+                raise UndoError("Can't undo during pack")
             return self._txn_undo(transaction_id)
         finally:
             self._lock_release()
@@ -869,13 +874,14 @@
         # Record pack time so we don't undo while packing
         self._lock_acquire()
         try:
-            # XXX _packt should just be a flag
-            if self._packt != ZERO:
+            while self._undoing:
+                # XXX poll for the thread running UndoSearch()
+                # to finish
+                time.sleep(0.1)
+            if self._packing:
                 # Already packing.
                 raise FileStorageError("Already packing")
-            # when undo sees _packt == None, it raises an error that
-            # says "can't undo during pack"
-            self._packt = None
+            self._packing = True
         finally:
             self._lock_release()
 
@@ -912,7 +918,7 @@
                 self._commit_lock_release()
                 self._lock_release()
             self._lock_acquire()
-            self._packt = ZERO
+            self._packing = False
             self._lock_release()
 
 
@@ -1181,10 +1187,9 @@
 
 class UndoSearch(FileStorageFormatter):
 
-    def __init__(self, file, pos, packt, first, last, filter=None):
+    def __init__(self, file, pos, first, last, filter=None):
         self._file = file
         self.pos = pos
-        self.packt = packt
         self.first = first
         self.last = last
         self.filter = filter
@@ -1214,7 +1219,7 @@
         if self.pos < 1024:
             return None
         h = self._read_txn_header(self.pos)
-        if h.tid < self.packt or h.status == 'p':
+        if h.status == 'p':
             self.stop = 1
             return None
         assert h.status == " "