From f0bf3aad482b53b752212cabc20514529d1f70ff Mon Sep 17 00:00:00 2001
From: Jonathan Warren <me@jonwarren.org>
Date: Sat, 7 Sep 2013 18:23:20 -0400
Subject: [PATCH] use locks when accessing dictionary inventory

---
 src/class_objectHashHolder.py  |  2 +-
 src/class_receiveDataThread.py | 14 +++++++++-----
 src/class_singleCleaner.py     | 32 +++++++++++++++++++-------------
 3 files changed, 29 insertions(+), 19 deletions(-)

diff --git a/src/class_objectHashHolder.py b/src/class_objectHashHolder.py
index 9c392765..90df7fd9 100644
--- a/src/class_objectHashHolder.py
+++ b/src/class_objectHashHolder.py
@@ -1,5 +1,5 @@
 # objectHashHolder is a timer-driven thread. One objectHashHolder thread is used
-# by each sendDataThread. It uses it whenever a sendDataThread needs to
+# by each sendDataThread. The sendDataThread uses it whenever it needs to
 # advertise an object to peers. Instead of sending it out immediately, it must
 # wait a random number of seconds for each connection so that different peers
 # get different objects at different times. Thus an attacker who is
diff --git a/src/class_receiveDataThread.py b/src/class_receiveDataThread.py
index a8b38bc4..e751cef0 100644
--- a/src/class_receiveDataThread.py
+++ b/src/class_receiveDataThread.py
@@ -298,11 +298,12 @@ class receiveDataThread(threading.Thread):
                 bigInvList[hash] = 0
         # We also have messages in our inventory in memory (which is a python
         # dictionary). Let's fetch those too.
-        for hash, storedValue in shared.inventory.items():
-            if hash not in self.someObjectsOfWhichThisRemoteNodeIsAlreadyAware:
-                objectType, streamNumber, payload, receivedTime = storedValue
-                if streamNumber == self.streamNumber and receivedTime > int(time.time()) - shared.maximumAgeOfObjectsThatIAdvertiseToOthers:
-                    bigInvList[hash] = 0
+        with shared.inventoryLock:
+            for hash, storedValue in shared.inventory.items():
+                if hash not in self.someObjectsOfWhichThisRemoteNodeIsAlreadyAware:
+                    objectType, streamNumber, payload, receivedTime = storedValue
+                    if streamNumber == self.streamNumber and receivedTime > int(time.time()) - shared.maximumAgeOfObjectsThatIAdvertiseToOthers:
+                        bigInvList[hash] = 0
         numberOfObjectsInInvMessage = 0
         payload = ''
         # Now let us start appending all of these hashes together. They will be
@@ -1496,11 +1497,14 @@ class receiveDataThread(threading.Thread):
                 print 'received getdata request for item:', hash.encode('hex')
 
             shared.numberOfInventoryLookupsPerformed += 1
+            shared.inventoryLock.acquire()
             if hash in shared.inventory:
                 objectType, streamNumber, payload, receivedTime = shared.inventory[
                     hash]
+                shared.inventoryLock.release()
                 self.sendData(objectType, payload)
             else:
+                shared.inventoryLock.release()
                 queryreturn = sqlQuery(
                     '''select objecttype, payload from inventory where hash=?''',
                     hash)
diff --git a/src/class_singleCleaner.py b/src/class_singleCleaner.py
index 07d56424..653a2461 100644
--- a/src/class_singleCleaner.py
+++ b/src/class_singleCleaner.py
@@ -32,19 +32,20 @@ class singleCleaner(threading.Thread):
             shared.UISignalQueue.put((
                 'updateStatusBar', 'Doing housekeeping (Flushing inventory in memory to disk...)'))
             
-            with SqlBulkExecute() as sql:
-                for hash, storedValue in shared.inventory.items():
-                    objectType, streamNumber, payload, receivedTime = storedValue
-                    if int(time.time()) - 3600 > receivedTime:
-                        sql.execute(
-                            '''INSERT INTO inventory VALUES (?,?,?,?,?,?)''',
-                            hash,
-                            objectType,
-                            streamNumber,
-                            payload,
-                            receivedTime,
-                            '')
-                        del shared.inventory[hash]
+            with shared.inventoryLock: # If you use both the inventoryLock and the sqlLock, always use the inventoryLock OUTSIDE of the sqlLock.
+                with SqlBulkExecute() as sql:
+                    for hash, storedValue in shared.inventory.items():
+                        objectType, streamNumber, payload, receivedTime = storedValue
+                        if int(time.time()) - 3600 > receivedTime:
+                            sql.execute(
+                                '''INSERT INTO inventory VALUES (?,?,?,?,?,?)''',
+                                hash,
+                                objectType,
+                                streamNumber,
+                                payload,
+                                receivedTime,
+                                '')
+                            del shared.inventory[hash]
             shared.UISignalQueue.put(('updateStatusBar', ''))
             shared.broadcastToSendDataQueues((
                 0, 'pong', 'no data'))  # commands the sendData threads to send out a pong message if they haven't sent anything else in the last five minutes. The socket timeout-time is 10 minutes.
@@ -118,4 +119,9 @@ class singleCleaner(threading.Thread):
                     queryData = sqlQuery('''SELECT hash FROM inventory WHERE streamnumber=?''', streamNumber)
                     for row in queryData:
                         shared.inventorySets[streamNumber].add(row[0])
+                with shared.inventoryLock:
+                    for hash, storedValue in shared.inventory.items():
+                        objectType, streamNumber, payload, receivedTime = storedValue
+                        if streamNumber in shared.inventorySets:
+                            shared.inventorySets[streamNumber].add(hash)
             time.sleep(300)