Changeset 262 for branches/eraser6/DefaultPlugins/EraseFirstLast16KB.cs

Timestamp:

3/12/2008 7:19:44 AM (5 years ago)

Author:

lowjoel

Message:

-Missed out the Passes factor when calculating the amount of data to remove when executing a first/last 16kb erase
-Use the default method when computing everything!

File:

• branches/eraser6/DefaultPlugins/EraseFirstLast16KB.cs (modified) (3 diffs)

branches/eraser6/DefaultPlugins/EraseFirstLast16KB.cs

@@ -27 +27 @@
         public override long CalculateEraseDataSize(List<string> paths, long targetSize)
         {
-            //Simple. Number of files multiplied by 32kb.
-            return paths.Count * dataSize * 2;
+            //Amount of data required to be written.
+            long amountToWrite = 0;
+            if (paths == null)
+            {
+                if (targetSize <= dataSize)
+                    amountToWrite = targetSize;
+                else
+                    amountToWrite = dataSize * 2;
+            }
+            else
+                amountToWrite = paths.Count * dataSize * 2;
+
+            //The final amount has to be multiplied by the number of passes.
+            return amountToWrite * Method.Passes;
         }
 
@@ -41 +53 @@
                     "limited, since this is a self-limiting erasure method.");
 
-            //Try to retrieve the default erasure method.
-            ErasureMethod defaultMethod = ErasureMethodManager.GetInstance(
-                Globals.Settings.DefaultFileErasureMethod);
-
-            //If we are the default, use the default pseudorandom pass.
-            if (defaultMethod.GUID == GUID)
-                defaultMethod = ErasureMethodManager.GetInstance(new Guid(
-                    "{BF8BA267-231A-4085-9BF9-204DE65A6641}"));
+            ErasureMethod method = Method;
 
             //If the target stream is shorter than 16kb, just forward it to the default
@@ -54 +59 @@
             if (strm.Length < dataSize)
             {
-                defaultMethod.Erase(strm, erasureLength, prng, callback);
+                method.Erase(strm, erasureLength, prng, callback);
                 return;
             }
 
-            //Declare our local anonymous function to forward the progress event
-            //to the callback function.
-            float baseCompleted = 0;
-            OnProgress chainCallbackHandler = delegate(float currentProgress, int currentPass)
-            {
-                callback(baseCompleted + currentProgress / 2,
-                    (int)((baseCompleted * defaultMethod.Passes) + currentPass / 2));
-            };
-
             //Seek to the beginning and write 16kb.
             strm.Seek(0, SeekOrigin.Begin);
-            defaultMethod.Erase(strm, dataSize, prng, chainCallbackHandler);
-            baseCompleted = 0.5F;
+            method.Erase(strm, dataSize, prng, callback);
 
             //Seek to the end - 16kb, and write.
             strm.Seek(-dataSize, SeekOrigin.End);
-            defaultMethod.Erase(strm, long.MaxValue, prng, chainCallbackHandler);
+            method.Erase(strm, long.MaxValue, prng, callback);
+        }
+
+        private ErasureMethod Method
+        {
+            get
+            {
+                //Try to retrieve the default erasure method.
+                ErasureMethod defaultMethod = ErasureMethodManager.GetInstance(
+                    Globals.Settings.DefaultFileErasureMethod);
+
+                //If we are the default, use the default pseudorandom pass.
+                if (defaultMethod.GUID == GUID)
+                    defaultMethod = ErasureMethodManager.GetInstance(new Guid(
+                        "{BF8BA267-231A-4085-9BF9-204DE65A6641}"));
+
+                return defaultMethod;
+            }
         }