Basic UTF-8 support in ansi build so it can read UTF-8 .nlf files and LangStrings

git-svn-id: https://svn.code.sf.net/p/nsis/code/NSIS/trunk@6196 212acab6-be3b-0410-9dea-997c60f758d6

Source/utf.h

@@ -0,0 +1,43 @@
+/*
+ * utf.h
+ * 
+ * This file is a part of NSIS.
+ * 
+ * Copyright (C) 2011 Anders Kjersem
+ * 
+ * Licensed under the zlib/libpng license (the "License");
+ * you may not use this file except in compliance with the License.
+ * 
+ * Licence details can be found in the file COPYING.
+ * 
+ * This software is provided 'as-is', without any express or implied
+ * warranty.
+ *
+ */
+
+#include "Platform.h"
+#include <stdlib.h>
+#include <stdio.h>
+
+typedef unsigned short EXEHEADWCHAR_T;
+
+
+#ifdef _UNICODE
+typedef EXEHEADWCHAR_T EXEHEADTCHAR_T;
+
+#else // !_UNICODE
+typedef char EXEHEADTCHAR_T;
+
+#define ExeHeadTStrFree free
+inline EXEHEADTCHAR_T* ExeHeadTStrAlloc(UINT cb) {return (EXEHEADTCHAR_T*) malloc(cb);}
+extern EXEHEADTCHAR_T* UTF8ToExeHeadTStr(LPCSTR StrU8,UINT Codepage);
+
+#endif // ?_UNICODE
+
+
+/**
+ * Tries to peek at the first few bytes in the stream to determine if it is a UTF-8 BOM.
+ * If it is a UTF-8 BOM it will eat the BOM, 
+ * if it is not it tries its best to restore the data.
+ */
+extern bool IsUTF8BOM(FILE*fstrm);