1 files changed, 92 insertions, 0 deletions
diff --git a/other-licenses/7zstub/src/CPP/7zip/Compress/ByteSwap.cpp b/other-licenses/7zstub/src/CPP/7zip/Compress/ByteSwap.cpp
new file mode 100644
index 000000000..ee103afe7
--- /dev/null
+++ b/other-licenses/7zstub/src/CPP/7zip/Compress/ByteSwap.cpp
@@ -0,0 +1,92 @@
+// ByteSwap.cpp
+
+#include "StdAfx.h"
+
+#include "../../Common/MyCom.h"
+
+#include "../ICoder.h"
+
+#include "../Common/RegisterCodec.h"
+
+namespace NCompress {
+namespace NByteSwap {
+
+class CByteSwap2:
+  public ICompressFilter,
+  public CMyUnknownImp
+{
+public:
+  MY_UNKNOWN_IMP1(ICompressFilter);
+  INTERFACE_ICompressFilter(;)
+};
+
+class CByteSwap4:
+  public ICompressFilter,
+  public CMyUnknownImp
+{
+public:
+  MY_UNKNOWN_IMP1(ICompressFilter);
+  INTERFACE_ICompressFilter(;)
+};
+
+STDMETHODIMP CByteSwap2::Init() { return S_OK; }
+
+STDMETHODIMP_(UInt32) CByteSwap2::Filter(Byte *data, UInt32 size)
+{
+  const UInt32 kStep = 2;
+  if (size < kStep)
+    return 0;
+  size &= ~(kStep - 1);
+  
+  const Byte *end = data + (size_t)size;
+  
+  do
+  {
+    Byte b0 = data[0];
+    data[0] = data[1];
+    data[1] = b0;
+    data += kStep;
+  }
+  while (data != end);
+
+  return size;
+}
+
+STDMETHODIMP CByteSwap4::Init() { return S_OK; }
+
+STDMETHODIMP_(UInt32) CByteSwap4::Filter(Byte *data, UInt32 size)
+{
+  const UInt32 kStep = 4;
+  if (size < kStep)
+    return 0;
+  size &= ~(kStep - 1);
+  
+  const Byte *end = data + (size_t)size;
+  
+  do
+  {
+    Byte b0 = data[0];
+    Byte b1 = data[1];
+    data[0] = data[3];
+    data[1] = data[2];
+    data[2] = b1;
+    data[3] = b0;
+    data += kStep;
+  }
+  while (data != end);
+
+  return size;
+}
+
+REGISTER_FILTER_CREATE(CreateFilter2, CByteSwap2())
+REGISTER_FILTER_CREATE(CreateFilter4, CByteSwap4())
+
+REGISTER_CODECS_VAR
+{
+  REGISTER_FILTER_ITEM(CreateFilter2, CreateFilter2, 0x20302, "Swap2"),
+  REGISTER_FILTER_ITEM(CreateFilter4, CreateFilter4, 0x20304, "Swap4")
+};
+
+REGISTER_CODECS(ByteSwap)
+
+}}