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diff --git a/Frameworks/SPMySQLFramework/Source/SPMySQLConnection Categories/Locking.m b/Frameworks/SPMySQLFramework/Source/SPMySQLConnection Categories/Locking.m
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+++ b/Frameworks/SPMySQLFramework/Source/SPMySQLConnection Categories/Locking.m
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+//
+//  $Id$
+//
+//  Locking.m
+//  SPMySQLFramework
+//
+//  Created by Rowan Beentje (rowan.beent.je) on January 22, 2012
+//  Copyright (c) 2012 Rowan Beentje. All rights reserved.
+//
+//  Permission is hereby granted, free of charge, to any person
+//  obtaining a copy of this software and associated documentation
+//  files (the "Software"), to deal in the Software without
+//  restriction, including without limitation the rights to use,
+//  copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the
+//  Software is furnished to do so, subject to the following
+//  conditions:
+//
+//  The above copyright notice and this permission notice shall be
+//  included in all copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+//  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+//  OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+//  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+//  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+//  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+//  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+//  OTHER DEALINGS IN THE SOFTWARE.
+//
+//  More info at <http://code.google.com/p/sequel-pro/>
+
+// This class is private to the framework.
+
+#import "Locking.h"
+#import "SPMySQL Private APIs.h"
+
+@implementation SPMySQLConnection (Locking)
+
+
+/**
+ * Lock the connection. This must be done before performing any operation
+ * that is not thread safe, eg. performing queries or pinging.
+ */
+- (void)_lockConnection
+{
+
+    // We can only start a query when the condition is SPMySQLConnectionIdle
+	[connectionLock lockWhenCondition:SPMySQLConnectionIdle];
+    
+    // Set the condition to SPMySQLConnectionBusy
+    [connectionLock unlockWithCondition:SPMySQLConnectionBusy];
+}
+
+/**
+ * Attempt to lock the connection. If the connection is idle (unlocked), this method
+ * locks the connection and returns YES for success. The connection must afterward
+ * be unlocked using unlockConnection. If the connection is currently busy (locked),
+ * this method immediately returns NO and doesn't lock the connection.
+ */
+- (BOOL)_tryLockConnection
+{
+
+	// If the connection is already is use, return failure
+	if (![connectionLock tryLockWhenCondition:SPMySQLConnectionIdle]) {
+		return NO;
+	}
+
+	// We're allowed to use the connection; set it to busy, and return success
+	[connectionLock unlockWithCondition:SPMySQLConnectionBusy];
+	return YES;
+}
+
+
+/**
+ * Unlock the connection.
+ */
+- (void)_unlockConnection
+{
+
+    // Always lock the conditional lock before proceeding
+    [connectionLock lock];
+    
+    // Check if the connection actually was busy. If it wasn't busy,
+    // it means the connection may have been unlocked twice. This is
+    // potentially dangerous, so we log this to the console
+    if ([connectionLock condition] != SPMySQLConnectionBusy) {
+        NSLog(@"SPMySQLConnection: Tried to unlock the connection, but it wasn't locked.");
+    }
+    
+    // Since we connected with CLIENT_MULTI_RESULT, we must make sure there are not more results!
+    // This is still a bit of a dirty hack
+    if (state == SPMySQLConnected
+		&& mySQLConnection && mySQLConnection->net.vio && mySQLConnection->net.buff && mysql_more_results(mySQLConnection))
+	{
+        NSLog(@"SPMySQLConnection: Discarding unretrieved results. This is currently normal when using CALL.");
+        [self _flushMultipleResultSets];
+    }
+    
+    // Tell everyone that the connection is available again
+    [connectionLock unlockWithCondition:SPMySQLConnectionIdle];
+}
+
+@end