From 0d408831769bbdc463e908f837a3029086a0283f Mon Sep 17 00:00:00 2001
From: coderb <coderbri@gmail.com>
Date: Wed, 20 Dec 2017 11:19:30 -0500
Subject: [PATCH] unrar5: unpack wip

---
 .../FragmentedWindow.unpack50frag_cpp.cs      |  4 +-
 .../Compressors/Rar/UnpackV2017/Unpack.cs     |  4 ++
 .../Rar/UnpackV2017/Unpack.unpack50_cpp.cs    | 40 +++++++++++--------
 .../Compressors/Rar/UnpackV2017/unpack_hpp.cs |  4 +-
 4 files changed, 32 insertions(+), 20 deletions(-)

diff --git a/src/SharpCompress/Compressors/Rar/UnpackV2017/FragmentedWindow.unpack50frag_cpp.cs b/src/SharpCompress/Compressors/Rar/UnpackV2017/FragmentedWindow.unpack50frag_cpp.cs
index 32ebd57b..ca1b78df 100644
--- a/src/SharpCompress/Compressors/Rar/UnpackV2017/FragmentedWindow.unpack50frag_cpp.cs
+++ b/src/SharpCompress/Compressors/Rar/UnpackV2017/FragmentedWindow.unpack50frag_cpp.cs
@@ -126,10 +126,10 @@ public void CopyString(uint Length,uint Distance,ref size_t UnpPtr,size_t MaxWin
 }
 
 
-public void CopyData(byte *Dest,size_t WinPos,size_t Size)
+public void CopyData(byte[] Dest, size_t destOffset, size_t WinPos,size_t Size)
 {
   for (size_t I=0;I<Size;I++)
-    Dest[I]=this[WinPos+I];
+    Dest[destOffset+I]=this[WinPos+I];
 }
 
 
diff --git a/src/SharpCompress/Compressors/Rar/UnpackV2017/Unpack.cs b/src/SharpCompress/Compressors/Rar/UnpackV2017/Unpack.cs
index 8508b784..fdcd0df6 100644
--- a/src/SharpCompress/Compressors/Rar/UnpackV2017/Unpack.cs
+++ b/src/SharpCompress/Compressors/Rar/UnpackV2017/Unpack.cs
@@ -91,6 +91,10 @@ namespace SharpCompress.Compressors.Rar.UnpackV2017
         }
 
         public int PpmEscChar { get => this.PPMEscChar; set => this.PPMEscChar = value; } 
+
+        public static byte[] EnsureCapacity(byte[] array, int length) {
+            return array.Length < length ? new byte[length] : array;
+        }
     }
 }
 #endif
\ No newline at end of file
diff --git a/src/SharpCompress/Compressors/Rar/UnpackV2017/Unpack.unpack50_cpp.cs b/src/SharpCompress/Compressors/Rar/UnpackV2017/Unpack.unpack50_cpp.cs
index 57dfa466..73fb3722 100644
--- a/src/SharpCompress/Compressors/Rar/UnpackV2017/Unpack.unpack50_cpp.cs
+++ b/src/SharpCompress/Compressors/Rar/UnpackV2017/Unpack.unpack50_cpp.cs
@@ -325,31 +325,35 @@ void UnpWriteBuf()
         {
           uint BlockEnd=(BlockStart+BlockLength)&MaxWinMask;
 
-          FilterSrcMemory.Alloc(BlockLength);
-          byte *Mem=&FilterSrcMemory[0];
+          //x FilterSrcMemory.Alloc(BlockLength);
+          FilterSrcMemory = EnsureCapacity(FilterSrcMemory, checked((int)BlockLength));
+          byte[] Mem= FilterSrcMemory;
           if (BlockStart<BlockEnd || BlockEnd==0)
           {
             if (Fragmented)
-              FragWindow.CopyData(Mem,BlockStart,BlockLength);
+              FragWindow.CopyData(Mem,0,BlockStart,BlockLength);
             else
-              memcpy(Mem,Window+BlockStart,BlockLength);
+              //x memcpy(Mem,Window+BlockStart,BlockLength);
+              Array.Copy(Window, BlockStart, Mem, 0, BlockLength);
           }
           else
           {
-            size_t FirstPartLength=size_t(MaxWinSize-BlockStart);
+            size_t FirstPartLength=(size_t)(MaxWinSize-BlockStart);
             if (Fragmented)
             {
-              FragWindow.CopyData(Mem,BlockStart,FirstPartLength);
-              FragWindow.CopyData(Mem+FirstPartLength,0,BlockEnd);
+              FragWindow.CopyData(Mem,0,BlockStart,FirstPartLength);
+              FragWindow.CopyData(Mem,FirstPartLength,0,BlockEnd);
             }
             else
             {
-              memcpy(Mem,Window+BlockStart,FirstPartLength);
-              memcpy(Mem+FirstPartLength,Window,BlockEnd);
+              //x memcpy(Mem,Window+BlockStart,FirstPartLength);
+              Array.Copy(Window, BlockStart, Mem, 0, FirstPartLength);
+              //x memcpy(Mem+FirstPartLength,Window,BlockEnd);
+              Array.Copy(Window, 0, Mem, FirstPartLength,BlockEnd);
             }
           }
 
-          byte *OutMem=ApplyFilter(Mem,BlockLength,flt);
+          byte[] OutMem=ApplyFilter(Mem,BlockLength,flt);
 
           Filters[I].Type=FILTER_NONE;
 
@@ -388,8 +392,10 @@ void UnpWriteBuf()
   }
 
   // Remove processed filters from queue.
-  size_t EmptyCount=0;
-  for (size_t I=0;I<Filters.Count;I++)
+  // sharpcompress: size_t -> int
+  int EmptyCount=0;
+  // sharpcompress: size_t -> int
+  for (int I=0;I<Filters.Count;I++)
   {
     if (EmptyCount>0)
       Filters[I-EmptyCount]=Filters[I];
@@ -419,9 +425,9 @@ void UnpWriteBuf()
 }
 
 
-byte* ApplyFilter(byte *Data,uint DataSize,UnpackFilter Flt)
+byte[] ApplyFilter(byte[] Data,uint DataSize,UnpackFilter Flt)
 {
-  byte *SrcData=Data;
+  byte[] SrcData=Data;
   switch(Flt.Type)
   {
     case FILTER_E8:
@@ -484,8 +490,10 @@ byte* ApplyFilter(byte *Data,uint DataSize,UnpackFilter Flt)
         // values here, since RAR5 uses only 5 bits to store channel.
         uint Channels=Flt.Channels,SrcPos=0;
 
-        FilterDstMemory.Alloc(DataSize);
-        byte *DstData=&FilterDstMemory[0];
+        //x FilterDstMemory.Alloc(DataSize);
+        FilterDstMemory = EnsureCapacity(FilterDstMemory, checked((int)DataSize));
+
+        byte[] DstData=FilterDstMemory;
 
         // Bytes from same channels are grouped to continual data blocks,
         // so we need to place them back to their interleaving positions.
diff --git a/src/SharpCompress/Compressors/Rar/UnpackV2017/unpack_hpp.cs b/src/SharpCompress/Compressors/Rar/UnpackV2017/unpack_hpp.cs
index 893c6d2f..0c4cc62f 100644
--- a/src/SharpCompress/Compressors/Rar/UnpackV2017/unpack_hpp.cs
+++ b/src/SharpCompress/Compressors/Rar/UnpackV2017/unpack_hpp.cs
@@ -271,8 +271,8 @@ internal partial class Unpack
     byte *ReadBufMT;
 #endif
 
-    readonly List<byte> FilterSrcMemory = new List<byte>();
-    readonly List<byte> FilterDstMemory = new List<byte>();
+    byte[] FilterSrcMemory = new byte[0];
+    byte[] FilterDstMemory = new byte[0];
 
     // Filters code, one entry per filter.
     readonly List<UnpackFilter> Filters = new List<UnpackFilter>();