First commit.

FileMapping.cpp

@@ -0,0 +1,87 @@
+// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
+// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
+// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
+// PARTICULAR PURPOSE.
+//
+// Copyright (c) Microsoft Corporation. All rights reserved
+
+#include "Private.h"
+#include "FileMapping.h"
+#include "Globals.h"
+
+//---------------------------------------------------------------------
+//
+// ctor
+//
+//---------------------------------------------------------------------
+
+CFileMapping::CFileMapping() : CFile()
+{
+    _fileMappingHandle = nullptr;
+    _pMapBuffer = nullptr;
+}
+
+//---------------------------------------------------------------------
+//
+// dtor
+//
+//---------------------------------------------------------------------
+
+CFileMapping::~CFileMapping()
+{
+    if (_pMapBuffer)
+    {
+        UnmapViewOfFile(_pMapBuffer);
+        _pMapBuffer = nullptr;
+        _pReadBuffer = nullptr;
+    }
+    if (_fileMappingHandle)
+    {
+        CloseHandle(_fileMappingHandle);
+        _fileMappingHandle = nullptr;
+    }
+}
+
+//---------------------------------------------------------------------
+//
+// SetupReadBuffer
+//
+//---------------------------------------------------------------------
+
+BOOL CFileMapping::SetupReadBuffer()
+{
+    if (_fileSize > sizeof(WCHAR))
+    {
+        //
+        // Read file in file mapping
+        //
+        _fileMappingHandle = CreateFileMapping(_fileHandle, NULL, PAGE_READONLY, 0, 0, NULL);
+        if (_fileMappingHandle)
+        {
+            _pMapBuffer = (const WCHAR *)MapViewOfFile(_fileMappingHandle, FILE_MAP_READ, 0, 0, 0);
+            if (_pMapBuffer)
+            {
+                if (IsTextUnicode(_pMapBuffer, (int)_fileSize, NULL))
+                {
+                    _pReadBuffer = (WCHAR*)_pMapBuffer;
+
+                    // skip Unicode byte order mark
+                    if (*((WCHAR*)_pMapBuffer) == Global::UnicodeByteOrderMark)
+                    {
+                        _pReadBuffer++;
+                        _fileSize--;
+                    }
+                    return TRUE;
+                }
+
+                UnmapViewOfFile(_pReadBuffer);
+                _pReadBuffer = nullptr;
+            }
+
+            CloseHandle(_fileMappingHandle);
+            _fileMappingHandle = nullptr;
+        }
+    }
+
+    return FALSE;
+}