Improved hash search

Ch4rg3r · Jun 17, 2017 · 7073b91 · 7073b91
1 parent 54ccb8a
commit 7073b91
Showing 1 changed file with 25 additions and 13 deletions.
diff --git a/RageLib/Helpers/HashSearch.cs b/RageLib/Helpers/HashSearch.cs
@@ -1,5 +1,5 @@
 /*
-    Copyright(c) 2015 Neodymium
+    Copyright(c) 2017 Neodymium
 
     Permission is hereby granted, free of charge, to any person obtaining a copy
     of this software and associated documentation files (the "Software"), to deal
@@ -31,37 +31,49 @@ namespace RageLib.Helpers
     public static class HashSearch
     {
         private const int BLOCK_LENGTH = 1048576;
-        private const int ALIGN_LENGTH = 16;
 
-        public static byte[] SearchHash(Stream stream, byte[] hash, int length = 32)
+        public static byte[] SearchHash(Stream stream, byte[] hash, int alignment = 1, int length = 32)
         {
-            return SearchHashes(stream, new List<byte[]> { hash }, length)[0];
+            return SearchHashes(stream, new List<byte[]> { hash }, alignment, length)[0];
         }
 
-        public static byte[][] SearchHashes(Stream stream, IList<byte[]> hashes, int length = 32)
+        public static byte[][] SearchHashes(Stream stream, IList<byte[]> hashes, int alignment = 1, int length = 32)
         {
+            var buf = new byte[stream.Length];
+            stream.Position = 0;
+            stream.Read(buf, 0, buf.Length);
+
             var result = new byte[hashes.Count][];           
 
             Parallel.For(0, (int)(stream.Length / BLOCK_LENGTH), (int k) => {
 
+                var tmp = new byte[length];
+
                 var hashProvider = new SHA1CryptoServiceProvider();
-                var buffer = new byte[length];
-                for (int i = 0; i < (BLOCK_LENGTH / ALIGN_LENGTH); i++)
+                //var buffer = new byte[length];
+                for (int i = 0; i < (BLOCK_LENGTH / alignment); i++)
                 {
-                    var position = k * BLOCK_LENGTH + i * ALIGN_LENGTH;
+                    var position = k * BLOCK_LENGTH + i * alignment;
                     if (position >= stream.Length)
                         continue;
 
-                    lock (stream)
+
+
+                    //lock (stream)
+                    //{
+                    //    stream.Position = position;
+                    //    stream.Read(buffer, 0, length);
+                    //}
+                    for (int t = 0; t < length; t++)
                     {
-                        stream.Position = position;
-                        stream.Read(buffer, 0, length);
+                        tmp[t] = buf[position + t];
                     }
 
-                    var hash = hashProvider.ComputeHash(buffer);
+
+                    var hash = hashProvider.ComputeHash(tmp);
                     for (int j = 0; j < hashes.Count; j++)
                         if (hash.SequenceEqual(hashes[j]))
-                            result[j] = (byte[])buffer.Clone();
+                            result[j] = (byte[])tmp.Clone();
                 }